EA005326B1 - Natural gas liquefaction - Google Patents

Abstract

A process for liquefying natural gas (50) in conjunction with producing a liquid stream containing predominantly hydrocarbons heavier than methane (41) is disclosed. In the process, the natural gas stream to be liquefied (31) is partially cooled, expanded to an intermediate pressure (14,15), and supplied to a distillation column (19). The bottom product (41) from this distillation column preferentially contains the majority of any hydrocarbons heavier than methane that would otherwise reduce the purity of the liquefied natural gas (50). The residual gas stream (37) from the distillation column (19) is compressed (16) to a higher intermediate pressure, cooled under pressure (60) to condense it, and then expanded (61) to low pressure to form the liquefied natural gas stream.

Description

BACKGROUND OF THE INVENTION

This invention relates to a method for treating natural gas or other methane-rich gas streams in order to produce a liquefied natural gas (LNG) stream that has high methane purity, and a liquid stream predominantly containing hydrocarbons is heavier than methane.

Natural gas is usually produced from wells drilled in underground formations. It usually has a major share of methane, i.e. methane comprises at least 50 mol% of gas. Depending on the particular subterranean formation, natural gas also contains relatively smaller amounts of heavier hydrocarbons such as ethane, propane, butanes, pentanes and the like, as well as water, hydrogen, nitrogen, carbon dioxide and other gases.

Most of the natural gas is processed in gaseous form. The most common means for transporting natural gas from the wellhead to gas processing units and from there to natural gas consumers are pipelines for high pressure gas passage. In a number of circumstances, however, it was found necessary and / or desirable to liquefy natural gas, either for transportation or for use. In remote places, for example, often there is no pipeline infrastructure that would enable convenient transportation of natural gas to the market. In these cases, a much smaller specific volume of LNG relative to natural gas in the gaseous state can significantly reduce transportation prices by making it possible to deliver LNG using cargo ships and transport trucks.

Another circumstance for which liquefaction of natural gas may be useful is its use as a fuel for vehicle engines. In large metropolitan areas, there are fleets of buses, taxis and trucks that can be driven by LNG if there is a cost-effective source of LNG. Such vehicles with LNG as fuel produce significantly less air pollution due to the cleanliness of natural gas combustion compared to similar vehicles that are powered by gasoline and diesel engines, which burn hydrocarbons with a higher molecular weight. In addition, if LNG is of high purity (that is, when the methane purity is 95 mol% or higher), the amount of carbon dioxide (“greenhouse gas”) produced is significantly less due to the lower carbon / hydrogen ratio for methane compared to all other hydrocarbon fuels.

The present invention is mainly associated with the liquefaction of natural gas, while at the same time a liquid stream is produced as a by-product, consisting mainly of hydrocarbons heavier than methane, such as natural gas condensate (PGA), consisting of ethane, propane, butanes and heavier hydrocarbon components, liquefied petroleum gas (LPG) consisting of propane, butanes and heavier hydrocarbon components, or condensate consisting of butanes and heavier hydrocarbon components. Producing a by-product of a liquid stream has two important advantages: the LNG produced has a high methane purity, and the liquid by-product is a valuable product that can be used for many other purposes. A typical analysis of the natural gas stream that is processed in accordance with this invention is, in approximate molar percent, 84.2% methane, 7.9% ethane and other C ₂ components, 4.9% propane and other C ₃ components, 1.0% isobutane. 1.1% normal butane, 0.8% pentane plus, and the remainder is nitrogen and carbon dioxide. Sulfur-containing gases are sometimes also present.

There are a number of methods known for liquefying natural gas. For example, see Είπη, Abpap 1., Ogai1 b. Ιοίιηδοη. apb Teggu V. Toshypzop, 'ΈΝΟ Tes11po1od Gog OEGzyoge apb M1b-8sae Rkty. Rgoseebshdz оГ 1йе 8ееещу-№п111 Αηииа1 Сопуепбоп оГ 1ее баз Rgosezogz Azzogaayop, pp. 429-450, A11ap1a, Oeogscha, Magsy 13-15, 2000 apb K1kkacha, Uz1Shzidg Mazaak OySy, apb no. Procurement Azzos1aup, 8ap Aplosho, Tehaz, Magsy 12-14, 2001 for servicing a number of such processes. U.S. Patent Nos. 4,445,917; 4,525,185; 4,545,795; 4,755,200; 5,291,736; 5,363,655; 5,365,740; 5,600,969; 5,615,561; 5,651,269; 5,755,114; 5,893,274; 6,014,869; 6,062,041; 6,119,479; 6,125,653; 6.250.105 B1; 6.269.655 B1; 6.272.882 B1; 6,308,531 B1; 6,324,867 B1; and 6,347,532 B1 also describe related processes. These methods mainly include the stages in which natural gas is purified (by removing water and harmful compounds such as carbon dioxide and sulfur compounds), cooled, condensed and expanded. The cooling and condensation of natural gas can be accomplished in many different ways. Cascade cooling uses heat transfer from natural gas with several refrigerants with gradually lower boiling points, such as propane, ethane and methane. Alternatively, this heat transfer can be accomplished using a single refrigerant by evaporating the refrigerant at several different pressures. In "multi-component cooling", heat exchange of natural gas with one or more liquid refrigerants consisting of several refrigeration components instead of a plurality of single-component refrigerants is used. Wide

-1005326 natural gas can be carried out isentalpically (using, for example, the Joule-Thomson expansion), and isentropic (using, for example, a working turboexpander).

Regardless of the method used to liquefy the natural gas stream, it is usually required to remove a significant fraction of hydrocarbons heavier than methane before the methane-rich stream is liquefied. The reasons for this stage of hydrocarbon removal are numerous, including the need to control the calorific value of the LNG stream, as well as the value of these heavier hydrocarbon components as products with their own parameters. Unfortunately, little attention has been paid so far to the effectiveness of the hydrocarbon removal stage.

In accordance with the present invention, it has been found that a careful combination of the hydrocarbon removal step in the LNG liquefaction process can produce both LNG and a separate liquid product consisting of heavier hydrocarbons using significantly lower energy than prior art processes. The present invention, although it is applicable at lower pressures, is particularly advantageous in the treatment of feed gases in the range of 400 to 1500 ppm [2758 to 10342 kPa (a)] or higher.

For a better understanding of the present invention, reference is made to the following examples and drawings.

FIG. 1 is a process flow chart of a natural gas liquefaction plant adapted for the production of a by-product in the form of PGA in accordance with the present invention;

FIG. 2 is a pressure-enthalpy phase diagram for methane used to illustrate the advantages of the present invention with respect to prior art methods;

FIG. 3 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product in the form of PGA in accordance with the present invention;

FIG. 4 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product in the form of LNG in accordance with the present invention;

FIG. 5 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a condensate by-product in accordance with the present invention;

FIG. 6 is a flow chart of an alternative plant for liquefying natural gas adapted to produce a by-product in the form of a liquid stream in accordance with the present invention;

FIG. 7 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention;

FIG. 8 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention;

FIG. 9 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention;

FIG. 10 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention;

FIG. 11 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention;

FIG. 12 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention;

FIG. 13 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention;

FIG. 14 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention;

FIG. 15 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention;

2005326 FIG. 16 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention;

FIG. 17 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention;

FIG. 18 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention;

FIG. 19 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention;

FIG. 20 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention; and FIG. 21 is a flow chart of an alternative natural gas liquefaction plant adapted to produce a by-product as a liquid stream in accordance with the present invention.

In the following explanation of the above figures, tables are provided which summarize the flow rates calculated for typical process conditions. In the tables given here, flow rates (in moles per hour) are rounded to the nearest whole number for convenience. The total flow rates shown in the tables include all non-hydrocarbon components and, therefore, significantly more than the sum of the flow rates of hydrocarbon components. The temperatures shown are approximate values rounded to the nearest degree. It should also be noted that the design calculations of the processes made to compare the processes depicted in the figures are based on the assumption that there is no leakage of heat from the environment (or into it) into the process (or from it). The quality of commercially available insulating materials makes this a very rational assumption and one of those commonly made by those skilled in the art.

For convenience, process parameters are presented both in traditional British units, and in units of the International System of Units (SI). The molar flow rates given in the tables can be presented either as pound mol per hour or kilogram mol per hour. Energy expenditures given as horsepower (hp) and / or thousands of British thermal units per hour (MW / Ng) correspond to the established molar flow rates in lb · mol per hour. Energy expenditures presented in kilowatts (kW) correspond to the established molar flow rates in kg · mol per hour. Capacities indicated as pounds per hour (lb / h) correspond to the established molar flow rates per pound mol per hour. Productivities indicated as kilograms per hour (kg / h) correspond to the established molar charges in kilogram · mol per hour.

Description of the invention

Example 1

Turning now to FIG. 1, we will begin by illustrating a process in accordance with the present invention in which it is desired to produce as a by-product an NGC containing most of the ethane and heavier components in the natural gas feed stream. In this simulation of the present invention, the inlet gas enters the unit at 90 ° E [32 ° C] and 1285 ppm [8860 kPa (a)] as stream 31. If the inlet gas contains a concentration of carbon dioxide and / or sulfur compound that interfere with compliance product streams to specifications, these compounds are removed by appropriate pre-treatment of the feed gas (not shown). In addition, the feed stream is usually dehydrated to prevent the formation of hydrate (ice) under cryogenic conditions. A solid dehumidifier is commonly used for this purpose.

The feed stream 31 is cooled in the heat exchanger 10 by heat exchange with refrigerant streams and liquids on the side of the demethanizer reboiler at -68 ° E [-55 ° C] (stream 40). Note that in all cases, the heat exchanger 10 is either a plurality of individual heat exchangers, or one multi-pass heat exchanger, or any combination thereof. (The decision to use more than one heat exchanger for the indicated cooling purposes depends on a number of factors, including but not limited to the flow rate of the incoming gas, the size of the heat exchanger, flow temperatures, etc.). The cooled stream 31a enters the separator 11 at -30 ° E [-34 ° C] and 1278 ppm [8812 kPa (a)], in which the vapor (stream 32) is separated from the condensed liquid (stream 33).

The steam (stream 32) from the separator 11 is divided into two streams, 34 and 36. Stream 34, containing about 20% of the total steam, is combined with the condensed liquid stream 33 to form a stream 35. The combined stream 35 passes through the heat exchanger 13 in the ratio of heat exchange with the stream refrigerant 71e, whereby stream 35a cools and essentially condenses. Essentially

-3005326, the condensed stream 35a at -120 ° P [-85 ° C] is then expanded by flash evaporation, using an appropriate expansion device, such as a butterfly valve 14, to a working pressure (approximately 465 rya [3206 kPa (a)] of distillation column 19. During the expansion, part of the flow evaporates, resulting in cooling of the entire flow.In the process shown in Fig. 1, the expanded flow 35b leaving the throttle valve 14 reaches a temperature of -122 ° P [-86 ° C] and is fed to a middle place feed to the rectification section demethanization 19b tele- communications tower 19.

The remaining 80% of the steam from the separator 11 (stream 36) enters the working expansion machine 15, in which mechanical energy is extracted from this part of the supply under high pressure. In machine 15, the vapor is expanded substantially isentropically from a pressure of about 1278 ry [8812 kPa (a)] to the working pressure of the column, the expansion work cooling the expanded stream 36a to a temperature of about -103 ° P [-75 ° C]. Typical commercially available expanders have the ability to extract about 80-85% of the work, which theoretically has an ideal isentropic expansion. Recoverable work is often used to drive a centrifugal compressor (such as shown at 16), which can be used to re-compress gas from the top of the column (stream 38), for example. The expanded and partially condensed stream 36a is supplied as a feed to the distillation column 19 to a lower feed point in the middle of the column.

The demethanizer in the distillation column 19 is a conventional distillation column containing a plurality of vertically separated plates, one or more layers of a nozzle, or some combination of plates and nozzle. As is often the case with natural gas processing plants, a distillation column may consist of two sections. The upper section 19a is a separator in which the top supply is divided into the corresponding parts of steam and liquid, and into which the steam rising from the lower distillation section or demethanization section 19b is connected to the part of the steam (if any) from the top supply to form cold steam from the top of the demethanizer (stream 37), which leaves the top of the column at -135 ° P [-93 ° C]. The lower demethanization section 19b contains trays and / or a nozzle and provides the necessary contact between liquids dropping down and vapors rising up. The demethanization section also includes one or more reboilers (such as reboiler 20) that heat and vaporize a portion of the liquids passing down the columns to create stripping vapors of light fractions that extend to the top of the column. Stream 41 of the liquid product exits from the bottom of the column at 115 ° P [46 ° C], based on typical specifications for the ratio of methane to ethane of 0.020: 1 on a molar basis of the bottom product.

The steam from the top of the demethanizer (stream 37) is heated to 90 ° P [32 ° C] in the heat exchanger 24, and part of the heated steam from the top of the demethanizer is diverted for use as fuel gas (stream 48) for installation. (The amount of fuel gas to be discharged is largely determined by the fuel required for the machines and / or turbines that drive the gas compressors in the installation, such as the refrigerant compressors 64, 66 and 68 in this example). The rest of the heated steam from the top of the demethanizer (stream 38) is compressed by compressor 16, which is driven by expansion machines 15, 61 and 63. After cooling to cooler at outlet 25 to 100 ° P [38 ° C], stream 38b is then cooled to -123 ° P [-86 ° C] in the heat exchanger 24 by transverse heat exchange with cold steam from the top of the demethanizer, stream 37.

Stream 38c then enters heat exchanger 60 and is further cooled by a refrigerant stream 716. After cooling to an intermediate temperature, stream 38c is divided into two parts. The first part, stream 49, is additionally cooled in a heat exchanger 60 to -257 ° P [-160 ° C] to condense and supercool, after which it enters a working expansion machine 61, in which mechanical energy is extracted from the stream. In machine 61, fluid flow 49 expands substantially isentropically, from a pressure of approximately 562 pounds [3878 kPa (a)] to a storage pressure of LNG (15.5 pounds [107 kPa (a)]), slightly above atmospheric pressure. The expansion operation cools the expanded stream 49a to a temperature of about −258 ° P [-161 ° C], after which it is then sent to the LNG storage tank 62 in which the LNG product is stored (stream 50).

Stream 39, another portion of stream 38c, is diverted from heat exchanger 60 at -160 ° P [-107 ° C] and expanded by flash evaporation through a suitable expansion device, such as throttle valve 17, to the operating pressure of distillation column 19. In the process shown in FIG. 1, there is no evaporation in the expanded stream 39a, therefore, its temperature drops only slightly to -161 ° P [-107 ° C] at the outlet of the throttle valve 17. The expanded stream 39a is then fed to the separation section 19a in the upper part of the distillation column 19. Liquid , separated therein, becomes the top feed to the demethanization section 19b.

All cooling for flows 35 and 38c is provided by a closed loop refrigeration circuit. The working fluid for this cycle is a mixture of hydrocarbons and nitrogen, the composition of the mixture being adjusted as necessary to provide the required temperature of the refrigerant during condensation at the appropriate pressure using an available cooling medium. In this case, condensation is assumed using cooling water, therefore a mixture of refrigerants, consisting of nitrogen, methane, ethane, propane and heavier hydrocarbons, is used to simulate

-4005326 of the process of FIG. 1. The composition of the stream in approximate molar percent is 7.5% nitrogen, 41.0% methane, 41.5% ethane and 10.0% propane, with the remainder being heavier hydrocarbons.

The refrigerant stream 71 exits the outlet of the cooler 69 at 100 ° P [38 ° C] and 607 rya [485 kPa (a)]. It enters the heat exchanger 10 and is cooled to -31 ° P [-35 ° C] and partially condensed through a partially heated expanded stream of refrigerant 71B and other refrigerant streams. To simulate FIG. 1, it has been suggested that these other refrigerant flows are commercial grade propane refrigerant at three different temperatures and pressures. The partially condensed refrigerant stream 71a then enters the heat exchanger 13 for further cooling to -114 ° P [-81 ° C] through a partially heated expanded refrigerant stream 71e, condenses and partially cools the refrigerant (stream 71b). The refrigerant is subsequently supercooled to 257 ° P [-160 ° C] in the heat exchanger 60 by means of an expanded refrigerant stream 716. The supercooled liquid stream 71c enters a working expansion machine 63, in which mechanical energy is extracted from the stream when it expands essentially isentropically from a pressure of about 586 rya [4040 kPa (a)] to about 34 grove [234 kPa (a)]. During expansion, part of the vapor evaporates, as a result of which the entire stream is cooled to -263 ° P [-164 ° C] (stream 716). The expanded stream 716 is then returned to heat exchangers 60, 13 and 10, where it provides cooling for stream 38c, stream 35 and refrigerant (streams 71, 71a and 71b) when it evaporates and overheats.

Superheated refrigerant vapor (stream 71d) exits heat exchanger 10 at 93 ° P [34 ° C] and is compressed in three stages to 617 rya [4254 kPa (a)]. Each of the three compression stages (refrigerant compressors 64, 66 and 68) is driven by an additional energy source and is accompanied by a cooler (coolers at the outlet 65, 67 and 69) to remove the heat of compression. The compressed stream 71 from the outlet of the refrigerator 69 is returned to the heat exchanger 10 to complete the cycle.

The total flow rates and energy costs in the process shown in FIG. 1 are shown in the following table.

Table 1 (Fig. 1)

Total flow rate - lb mol / h [kg mol / h]

Flow Methane Ethane Propane Butanych Total 31 40977 3861 2408 1404 48656 32 32360 2675 1469 701 37209 33 8617 1186 939 703 11447 34 6472 535 294 140 7442 36 25888 2140 1175 561 29767 37 47771 223 0 0 48000 39 6867 32 0 0 6900 41 73 3670 2408 1404 7556 48 3168 fifteen 0 0 3184 fifty 37736 176 0 0 37916

Extracts in Freight One *

Ethane

95.06%

Propane

100.00%

Butanych

100.00%

Performance

308147 lb / h [308147

LNG Product

Performance

610813 lb / h [610813 kg / h]

Purity

99.52%

Lower calorific value

Ability

912.3 wti / ssg [33.99 MJ / m ³ ]

Energy

Refrigerant compression

103957 hp [170904 kW]

Propane compression

33815 hp [55591 kW]

Total compression

137772 hp

Heat used

Reboiler demethanizer

29364 ΜΒΤϋ / Ng (Based on rounded flow rates)

The efficiency of LNG production processes is usually compared using the required “specific energy consumption”, which is the ratio of the total compression energy during cooling to the total liquid capacity. Published information on the specific energy consumption for prior art processes for LNG production shows that it ranges from 0.168 hp-h / lb [0.276 kWh / kg] to 0.182 hp-h / lb [0.300 kWh / kg], which is assumed to be based on a 340-day workflow rate for a LNG plant. On the same basis, the specific energy consumption of FIG. 1 design of this art

-5005326 to the rate of friction is 0.161 hp-h / lb [0.265 kWh / kg], which gives an increase in efficiency of 4-13% over the processes of the prior art. It should further be noted that the specific energy consumption in the processes of the prior art is based on the production of only liquid CIS streams (C ₃ and heavier hydrocarbons) or condensate (C ₄ and heavier hydrocarbons) as by-products, with relatively low recovery values, rather than a liquid PGC stream (C ₂ or heavier hydrocarbons), as shown in this example of the present invention. Prior art processes require much more cooling energy to produce as a byproduct of an NGL stream instead of a LPG stream or a condensate stream.

There are two main factors that are important in enhancing the effectiveness of the present invention. The first factor can be understood by examining the thermodynamics of the liquefaction process when it is applied to a high-pressure gas stream, such as the one in this example.

Since methane is the main component in this stream, the thermodynamic parameters of methane can be used to compare the liquefaction cycle used in prior art processes compared to the cycle used in the present invention. In FIG. Figure 2 shows the pressure-enthalpy phase diagram for methane. In most prior art liquefaction cycles, all gas stream cooling is performed when the stream is at high pressure (line A-B), after which the stream then expands (line B-C) to the pressure in the LNG storage tank (slightly more than Atmosphere pressure). This expansion stage can be used in a working expansion machine, which usually has the ability to extract about 7580% of the work, which is theoretically available in ideal isentropic expansion. In the interest of simplification, a complete isentropic expansion is shown in FIG. 2 for line BC. Even so, the decrease in enthalpy created by this expansion work is very small, because the lines of constant entropy are close to the vertical in the liquid phase of the phase diagram.

The opposite is the liquefaction cycle of the present invention. After partial cooling at high pressure (line A-A '), the gas stream then performs an expansion work (line A'-A) to an intermediate pressure. (Again, completely isentropic expansion is shown in the interest of simplification). The rest of the cooling is performed at an intermediate pressure (line AB), and the flow then expands (line B'C) to the pressure in the LNG storage tank. Since the constant entropy lines are inclined less steeply in the vapor region of the phase diagram, a much larger decrease in enthalpy is provided in the first stage of expansion work (line A'-A) of the present invention. Thus, the total amount of cooling required for the present invention (the sum of lines A-A 'and AB) is less than the cooling required for processes of the prior art (line AB), lowering the cooling (and therefore cooling compression) required to liquefy a gas stream.

A second factor explaining the improved efficiency of the present invention is the best performance of hydrocarbon distillation plants at low operating pressures. The hydrocarbon removal step in most prior art processes is performed at high pressure using a scrubber column that uses cold liquid hydrocarbons as an absorbent stream to remove heavier hydrocarbons from the incoming gas stream. The operation of the scrubber column at high pressure is not very effective due to the fact that there is a side absorption of a significant fraction of methane and ethane from the gas stream, which must subsequently be steamed from the absorbing liquid and cooled to become part of the LNG product. In the present invention, the hydrocarbon removal step is carried out at an intermediate pressure at which vapor-liquid equilibrium is much more preferable, resulting in a very efficient recovery of the desired heavier hydrocarbons in the liquid by-product stream.

Example 2

If the specifications for the LNG product make it possible to extract most of the ethane contained in the feed gas into the LNG product, a simpler embodiment of the present invention can be used. In FIG. 3 shows such an alternative embodiment. The composition of the inlet gas and the conditions expected in the process of FIG. 3 are the same as in FIG. 1. Accordingly, the process of FIG. 3 can be compared with the design depicted in figure 1.

In the process simulation of FIG. 3, the inlet gas cooling, separation and expansion scheme for the PGA extraction section is basically the same as that used in FIG. 1. The inlet gas enters the unit at 90 ° E [32 ° C] and 1285 rya [8860 kPa (a)] as stream 31 and is cooled in heat exchanger 10 by heat exchange with refrigerant flows and liquids from the demethanizer reboiler side at -35 ° E [-37 ° C] (stream 40). The cooled stream 31a enters the separator 11 at -30 ° E [-34 ° C] and 1278 rya [8812 kPa (a)], in which the vapor (stream 32) is separated from the condensed liquid (stream 33).

The vapor (stream 32) from the separator 11 is divided into two streams 34 and 36. The stream 34, containing about 20% of the total steam, is combined with the condensed liquid stream 33 to form a stream 35.

-6005326

The combined stream 35 passes through the heat exchanger 13 in a heat exchange ratio with the refrigerant stream 71e, as a result of which the stream 35a cools and essentially condenses. The substantially condensed stream 35a at -120 ° P [-85 ° C] is then expanded by flash evaporation, using an appropriate expansion device, such as a butterfly valve 14, to an operating pressure (approximately 465 p81a [3206 kPa (a)]) of the distillation column 19. During the expansion, part of the stream evaporates, as a result of which the entire stream is cooled. In the process shown in FIG. 3, the expanded stream 35b exiting the throttle valve 14 reaches a temperature of −122 ° P [-86 ° C] and is supplied to the separation section at the top of the distillation column 19. The liquids separated here become fed from above into the demethanization section at the bottom parts of the distillation column 19.

The remaining 80% of the steam from the separator 11 (stream 36) enters the working expansion machine 15, in which mechanical energy is extracted from this part of the supply under high pressure. In machine 15, the vapor is expanded substantially isentropically from a pressure of about 1278 ry [8812 kPa (a)] to the working pressure of the column, the expansion work cooling the expanded stream 36a to a temperature of about -103 ° P [-75 ° C]. The expanded and partially condensed stream 36a is supplied as being supplied to the distillation column 19 to a feed point in the middle of the column.

Cold steam from the top of the demethanizer (stream 37) leaves the top of distillation column 19 at -123 ° P [-86 ° C]. Stream 41 of the liquid product, which leaves the bottom of the column at 118 ° P [48 ° C], corresponds to typical specifications for the ratio of methane to ethane of 0.020: 1 on a molar basis of the bottom product.

The steam from the top of the demethanizer (stream 37) is heated to 90 ° P [32 ° C] in the heat exchanger 24 and part (stream 48) is then diverted to be used as fuel gas for the installation. The remainder of the heated steam from the top of the demethanizer (stream 49) is compressed by compressor 16. After cooling to 100 ° P [38 ° C] in the cooler at outlet 25, stream 49b is then cooled to -112 ° P [-80 ° C] in the heat exchanger 24 by lateral heat exchange with cold steam from the top of the demethanizer flow 37.

Stream 49c then enters the heat exchanger 60 and is further cooled by a refrigerant stream 716 to −257 ° P [-160 ° C] to condense and supercool, after which it enters a working expansion machine 61, in which mechanical energy is extracted from the stream. In machine 61, fluid flow 49 expands substantially isentropically from a pressure of approximately 583 pounds [4021 kPa (a)] to a storage pressure of LNG (15.5 pounds [107 kPa (a)]), slightly above atmospheric pressure. The expansion operation cools the expanded stream 49e to a temperature of about −258 ° P [-161 ° C], after which it is then sent to the LNG storage tank 62 in which the LNG product is stored (stream 50).

Similarly to the method of FIG. 1, all cooling of the streams 35 and 49c is provided by a closed-loop cooling circuit. The composition of the stream used as the working fluid in the cycle for the method of FIG. 3 in approximate molar percent is 7.5% nitrogen, 40.0% methane, 42.5% ethane and 10.0% propane, the remainder being heavier hydrocarbons. The flow of refrigerant 71 leaves the cooler at outlet 69 at 100 ° P [38 ° C] and 607 rya [4185 kPa (a)]. It enters the heat exchanger 10 and is cooled to -31 ° P [-35 ° C] and partially condensed by means of a partially heated expanded stream of refrigerant 71 £ and by other flows of refrigerants. To simulate FIG. 3 it was suggested that these other refrigerant flows are commercial grade propane refrigerant at three different temperatures and pressures. The partially condensed refrigerant stream 71a then enters the heat exchanger 13 for further cooling to -121 ° P [-85 ° C] by means of a partially heated expanded refrigerant stream 71e, condensation and partial supercooling of the refrigerant (stream 71b). The refrigerant is subsequently supercooled to -257 ° P [-160 ° C] in the heat exchanger 60 by means of an expanded refrigerant stream 716. The supercooled liquid stream 71c enters a working expansion machine 63, in which mechanical energy is extracted from the stream when it expands essentially isentropically from a pressure of approximately 586 rya [4040 kPa (a)] to approximately 34 rya [234 kPa (a)]. During expansion, part of the stream evaporates, as a result of which the entire stream is cooled to -263 ° P [-164 ° C] (stream 716). The expanded stream 716 is then returned to heat exchangers 60, 13 and 10, where it provides cooling for stream 38c, stream 35 and refrigerant (streams 71, 71a and 71b) when it evaporates and overheats.

Superheated refrigerant vapor (stream 71d) exits heat exchanger 10 at 93 ° P [34 ° C] and is compressed in three stages to 617 rya [4254 kPa (a)]. Each of the three compression stages (refrigerant compressors 64, 66 and 68) is driven by an additional energy source and is accompanied by a cooler (coolers at the outlet 65, 67 and 69) to remove the heat of compression. The compressed stream 71 from the cooler at the exit 69 is returned to the heat exchanger 10 to complete the cycle.

The total flow rates and energy costs in the process shown in FIG. 1 are shown in the following table.

-7005326

Total flow rate - lb mol / h [kg mol / h]

Flow

Methane

40977

32360

6472

25888

40910

2969

Ethane

3861

2675

1186

535

2140

480

3381

Propane

2408

1469

939

294

1175

2346

Propane

1404

701

703

140

561

1397

Total

48656

37209

11447

7442

29767

41465

7191

3009

Table II (Fig. 3)

38456

37941

445

Extracts in Freight One *

Ethane 87.57% Propane 97.41% Bhutans + 99.47% Performance 296175 lb / h [296175 kg / h] LNG Product Performance 625 152 lb / h [625152 kg / h] Purity* 98.66% Lower calorific value Ability 919.7 wti / ssg [34.27 MJ / m ³ ] Energy Refrigerant compression 96,560 hp [158743 kW] Propane compression 34724 hp [57086 kW] Total compression 131284 hp [215829 kW] Heat used Reboiler demethanizer 22177 MW / Ng [14326 kW]

(Based on rounded flow rates)

Assuming that the rate of operation is 340 days per year for an LNG production facility, the specific energy consumption for the design of FIG. 3 of the present invention is 0.153 hp-h / lb [0.251 kWh / kg]. Compared to prior art processes, the efficiency increase is 10-20% for the embodiment of FIG. 3. As previously noted for the design of FIG. 1, this increase in efficiency becomes possible according to the present invention, even if, as a by-product, PGC is produced, and not LPG or condensate, which are produced as a by-product in prior art processes.

Compared to the embodiment of FIG. 1, the embodiment of FIG. 3 of the present invention requires about 5% less power per unit of fluid produced. Thus, for a given amount of available compressor power, in the embodiment of FIG. 3, approximately 5% more natural gas can be liquefied than in the embodiment of FIG. 1 by extracting less C ₂ and heavier hydrocarbons into a by-product of the Freight One. The choice between the designs of FIG. 1 and 3 of the present invention for a particular application will be mainly dictated either by the value in money terms of the heavier hydrocarbons in the FGC product compared to their corresponding value in the LNG product, or by the calorific value of the LNG product (since the calorific value of LNG produced through design in Fig. 1, lower than the calorific value of LNG produced through the design of Fig. 3).

Example 3

If the specifications for the LNG product make it possible to extract most of the ethane contained in the feed gas into the LNG product, or if there is no market in place for a liquid by-product containing ethane, an alternative embodiment of the present invention, such as that shown in FIG. 4, can be used to produce a CIS by-product stream. The composition of the inlet gas and the conditions expected in the process of FIG. 4 are similar to those in FIG. 1 and 3. Accordingly, the process of FIG. 4 can be compared with the designs depicted in FIG. 1 and 3.

In the process simulation of FIG. 4, the incoming gas enters the installation at 90 ° G [32 ° C] and 1285 p ₈ 1a [8860 kPa (a)] as stream 31 and is cooled in the heat exchanger 10 by heat exchange with coolant flows and flash liquids from the separator at -46 ° G [-43 ° C] (stream 33a). Cooled at-8005326 current 31a enters the separator 11 at -1 ° P [-18 ° C] and 1278 p81a [8812 kPa (a)], where the vapor (stream 32) is separated from the condensed liquid (stream 33).

Steam (stream 32) from the separator 11 enters the working expansion machine 15, in which mechanical energy is extracted from this part of the supply under high pressure. In machine 15, the vapor is expanded substantially isentropically from a pressure of approximately 1278 psi [8812 kPa (a)] to a pressure of approximately 440 psi [3034 kPa (a)] (operating pressure of the separator / absorber column 18), the expansion work cooling the expanded a stream 32a to a temperature of about −81 ° P [−63 ° C]. The expanded and partially condensed stream 32a is supplied to the absorption section 18b at the bottom of the separator / absorber column 18. The liquid portion of the expanded stream is mixed with liquids dropping down from the absorption section, and the combined liquid stream 40 exits from the bottom of the separator / absorber column 18 at -86 ° P [-66 ° C]. The vapor portion of the expanded stream rises up through the absorption section and is in contact with a cold liquid that goes down to condense and absorb components C ₃ and heavier components.

The separator / absorber column 18 is a conventional distillation column comprising a plurality of vertically spaced plates, one or more layers of a nozzle, or some combination of plates and nozzle. As often happens in natural gas processing plants, a separator / absorber column can consist of two sections. The upper section 18a is a separator in which any steam contained in the top supply is separated from the corresponding liquid part, and in which the steam rising from the lower distillation section or absorption section 18b is combined with the steam part (if any) of the upper supply to form cold distillation stream 37, which leaves the top of the column. The lower absorption section 18b contains trays and / or a nozzle and provides the necessary contact between liquids that fall downward and vapors rising upward in order to condense and absorb components C3 and heavier components.

The combined liquid stream 40 from the bottom of the separator / absorber column 18 is returned to the heat exchanger 13 by the pump 26, where it (stream 40a) is heated when it is cooling the stream from the top of the deethanizer (stream 42) and the refrigerant (stream 71a). The combined liquid stream is heated to 24 ° P [-31 ° C], partially evaporating the stream 40b before it is fed, as a feed into the middle of the column, into the deethanizer 19. The separated liquid (stream 33) expands by instant evaporation to a pressure slightly higher than the working pressure in the deethanizer 19 by means of a throttle valve 12, cooling the stream 33 to -46 ° P [-43 ° C] (stream 33a) before it provides cooling for the inlet feed gas, as described previously. Stream 33b now at 85 ° P [29 ° C] then enters deethanizer 19 at the lower feed point in the middle of the column. In a deethanizer, methane and C ₂ components are evaporated from streams 40b and 33b. The deethanizer in column 19, operating at about 453 ry [3123 kPa (a)], is also a conventional distillation column containing a plurality of vertically spaced plates, one or more layers of a nozzle, or some combination of plates and nozzle. The deethanizer column may also consist of two sections: the upper separation section 18a, in which any steam contained in the top supply is separated from the corresponding liquid part, and in which the steam rising from the lower distillation section or deethanization section 19b is combined with the steam part ( if present) an upper feed to form a distillation stream 42 that exits from the top of the column; and a lower deethanization section 19b, which contains trays and / or a nozzle to provide the necessary contact between liquids dropping down and vapors rising up. The deethanization section 19b also includes one or more reboilers (such as reboiler 20) that heat and vaporize a portion of the liquid at the bottom of the column in order to create stripping vapors that extend up the column in order to drive the liquid product, stream 41, from methane and C ₂ components. A typical technical characteristic for a bottom liquid product is the ethane to propane ratio of 0.020: 1 on a molar basis. The liquid product stream 41 exits the bottom of the deethanizer at 214 ° P [101 ° C].

The operating pressure in the deethanizer 19 is maintained slightly higher than the operating pressure in the separator / absorber column 18.

This allows steam from the top of the deethanizer (stream 42) to create pressure in the stream through the heat exchanger 13 and, therefore, in the upper section of the separator / absorber column 18. In the heat exchanger 13, the flow from the top of the deethanizer at -19 ° P [-28 ° C] is directed in the heat exchange ratio with the combined liquid flow (stream 40a) from the bottom of the separator / absorber column 18 and instantly evaporates the refrigerant stream 71e, cooling the flow to -89 ° P [-67 ° C] (stream 42a) and partially condensing it. The partially condensed stream enters the reflux tank 22, where the condensed liquid (stream 44) is separated from the non-condensed vapor (stream 43). Stream 43 combines with the steam distillation stream (stream 37), leaving the top of the separator / absorber column 18 to form a cold residual gas stream 47. The condensed liquid (stream 44) is supplied under high pressure by the pump 23, after which the stream 44 is divided into two parts. One part, stream 45, is sent to the upper separation section of the separator / absorber column 18 to act as a cold liquid that contacts vapors rising upward through the absorption section. The other part is served

-9005326 to the deethanizer 19 as reflux stream 46, passing to the upper feed point to the deethanizer 19 at -89 ° P [-67 ° C].

The cold residual gas (stream 47) is heated from -94 ° P [-70 ° C] to 94 ° P [30 ° C] in the heat exchanger 24, and part (stream 48) is then diverted to be used as fuel gas on the installation. The remainder of the heated residual gas (stream 49) is compressed by compressor 16. After cooling to 100 ° P [38 ° C] in the refrigerator at outlet 25, stream 49b is further cooled to -78 ° P [-61 ° C] in the heat exchanger 24 by means of a cross exchange with cold residual gas, stream 47.

Stream 49c then enters heat exchanger 60 and is further cooled by a refrigerant stream 716 to -255 ° P [-160 ° C] to condense and supercool, after which it enters a working expansion machine 61, in which mechanical energy is extracted from the stream. In machine 61, fluid flow 49 expands substantially isentropically, from a pressure of about 648 rba [4465 kPa (a)] to a storage pressure of LNG (15.5 rya [107 kPa (a)]), slightly above atmospheric pressure. The expansion operation cools the expanded stream 49e to a temperature of about 256 ° P [-160 ° C], after which it is then sent to the LNG storage tank 62 in which the LNG product is stored (stream 50).

Similarly to the methods of FIG. 1 and 3, most of the cooling for stream 42 and all cooling for stream 49c is provided by a closed loop cooling circuit. The composition of the stream used as the working fluid in the cycle for the method of FIG. 4 in approximate molar percent is 8.7% nitrogen, 30.0% methane, 45.8% ethane and 11.0% propane, with the remainder being heavier hydrocarbons. The refrigerant stream 71 leaves the cooler at outlet 69 at 100 ° P [38 ° C] and 607 rya [4185 kPa (a)]. It enters the heat exchanger 10 and is cooled to -17 ° P [-27 ° C] and partially condensed through a partially heated expanded refrigerant stream of £ 71 and other refrigerant streams. To simulate FIG. 4, it was suggested that these other refrigerants are commercial grade propane refrigerant at three different temperatures and pressures. The partially condensed refrigerant stream 71a then enters the heat exchanger 13 for further cooling to -89 ° P [-67 ° C] by means of a partially heated expanded refrigerant stream 71e, further condensing the refrigerant (stream 71b). The refrigerant completely condenses and then is subcooled to -255 ° P [-160 ° C] in the heat exchanger 60 by means of an expanded refrigerant stream 716. The supercooled liquid stream 71c enters a working expansion machine 63, in which mechanical energy is extracted from the stream when it expands, essentially, isentropically from a pressure of about 586 rya [4040 kPa (a)] to about 34 grove [234 kPa (a)]. During expansion, part of the stream evaporates, as a result of which the entire stream is cooled to -264 ° P [-164 ° C] (stream 716). The expanded stream 716 is then returned to heat exchangers 60, 13 and 10, where it provides cooling for stream 49c, stream 42 and refrigerant (streams 71, 71a and 71b) when it evaporates and overheats.

Superheated refrigerant vapor (stream 71d) exits heat exchanger 10 at 90 ° P [32 ° C] and is compressed in three stages to 617 rya [4254 kPa (a)]. Each of the three compression stages (refrigerant compressors 64, 66 and 68) is driven by an additional energy source and is accompanied by a cooler (coolers at the outlet 65, 67 and 69) to remove the heat of compression. The compressed stream 71 from the cooler at the exit 69 is returned to the heat exchanger 10 to complete the cycle.

The total flow rates and energy costs in the process shown in FIG. 4 are shown in the following table.

Table III (Fig. 4)

Total flow rate - lb mol / h [kg mol / h]

Flow Methane Ethane Propane Wutans + Total 31 40977 3861 2408 1404 48656 32 38431 3317 1832 820 44405 33 2546 544 576 584 4251 37 36692 3350 nineteen 0 40066 40 5324 3386 1910 820 11440 41 0 48 2386 1404 3837 42 10361 6258 168 0 16789 43 4285 463 3 0 4753 44 6076 5795 165 0 12036 45 3585 3419 97 0 7101 46 2491 2376 68 0 4935 47 40977 3813 22 0 44819 48 2453 228 one 0 2684 fifty 38524 3585 21 0 42135 Extracts in Freight One * Propane 99.08% Bhutans + 100.00% Performance 197051 lbs / h [197051 kg / h]

LNG Product

-10005326

Performance 726,918 lb / h [726918 kg / hour Purity* 91.43% Lower calorific value Ability 969.9 wti / ssg [36.14 MJ / m ³ ] Energy Refrigerant compression 95424 hp [156876 kW] Propane compression 28060 hp [46130 kW] General compression 123484 hp [203006 kW] Heat used Reboiler demethanizer 55070 mvti / ng [35575 kW]

(Based on rounded flow rates)

Assuming that the performance indicator is 340 days per year for the LNG production facility, the specific energy consumption of FIG. 4 for the embodiment of the present invention is 0.143 hp-h / lb [0.236 kWh / kg]. Compared to prior art processes, the efficiency increase is 17-27% for the embodiment of FIG. 4.

Compared to the designs of FIG. 1 and 3, the embodiment of FIG. 4 of the present invention requires 6 to 11% less power per unit of fluid produced. Thus, for a given amount of available compression power in the embodiment of FIG. 4, approximately 6% more natural gas can be liquefied than in the embodiment of FIG. 1 or about 11% more natural gas than in the embodiment of FIG. 3 by extracting only C3 and heavier hydrocarbons as a by-product of the CIS. The choice between the design of FIG. 4 in comparison with the designs or in FIG. 1, or according to FIG. 3 of the present invention for a particular application will be mainly dictated either by the monetary value of ethane as part of the NGL product compared to its corresponding value in the LNG product, or by the calorific value of the LNG product (since the calorific value of LNG produced by the design of FIG. . 1 and 3, lower than the calorific value of LNG produced through the design of Fig. 4).

Example 4

If the specifications for the LNG product enable all ethane and propane contained in the feed gas to be extracted into the LNG product, or if there is no market for a liquid by-product containing ethane and propane, an alternative embodiment of the present invention, such as that shown in FIG. 5 can be used to produce a condensate by-product stream. The composition of the inlet gas and the conditions expected in the process of FIG. 5 are similar to those in FIG. 1, 3 and 4. Accordingly, the process of FIG. 5 can be compared with the designs depicted in FIG. 1, 3 and 4.

In the process simulation of FIG. 5, the incoming gas enters the installation at 90 ° E [32 ° C] and 1285 rya [8860 kPa (a)] as stream 31 and is cooled in heat exchanger 10 by heat exchange with coolant flows and flash liquids at high pressure from the separator at -37 ° E [-38 ° C] (stream 33b) and flash liquids at intermediate pressure from the separator at -37 ° E [-38 ° C] (stream 39b). The cooled stream 31a enters the high-pressure separator 11 at -30 ° E [-34 ° C] and 1278 rya [8812 kPa (a)], in which steam (stream 32) is separated from the condensed liquid (stream 33).

Steam (stream 32) from the high-pressure separator 11 enters the working expansion machine 15, in which mechanical energy is extracted from this part of the high-pressure feed. In machine 15, the vapor is expanded substantially isentropically from a pressure of approximately 1278 psi [8812 kPa (a)] to a pressure of approximately 635 psi [4378 kPa (a)], the expansion work cooling the expanded stream 32a to a temperature of about −83 ° E [-64 ° C]. The expanded and partially condensed stream 32a enters the intermediate pressure separator 18, where the vapor (stream 42) is separated from the condensed liquid (stream 39). The liquid from the intermediate pressure separator (stream 39) expands by flash evaporation to a pressure slightly higher than the operating pressure of the depropanizer 19 by means of a throttle valve 17, cooling stream 39 to -108 ° E [-78 ° C] (stream 39a) before it enters the heat exchanger 13 and heats up when it provides cooling to the residual gas stream 49 and the refrigerant stream 71a, and from there to the heat exchanger 10, in order to provide cooling for the incoming feed gas, as previously described. Stream 39c, which now has a temperature of −15 ° E [−26 ° C], then enters the depropanizer 19 at the top feed point in the middle of the column.

The condensed liquid, stream 33, from the high-pressure separator 11 expands by instant evaporation to a pressure slightly higher than the operating pressure of the depropanizer 19 by means of a throttle valve 12, cooling stream 33 to -93 ° E [-70 ° C] (stream 33a) before as it enters the heat exchanger 13, and heats up when it provides cooling to the residual gas stream 49 and the refrigerant stream 71a, and from there to the heat exchanger 10, in order to provide cooling of the incoming feed gas, as previously described. Stream 33c, which now has a temperature of 50 ° E [10 ° C], then enters

-11005326 depropanizer 19 at the lower feed point in the middle of the column. In a depropanizer, streams 39c and 33c are steamed from methane, components C ₂ and components C ₃ . The depropanizer in column 19 operating at approximately 385 rya [2654 kPa (a)] is a conventional distillation column containing a plurality of vertically spaced plates, one or more layers of a nozzle, or some combination of plates and nozzle. The depropanizer column may consist of two sections, the upper separation section 19a, in which any steam contained in the top feed is separated from the corresponding liquid part, and in which the steam rising from the lower distillation section or depropanization section 19b is combined with the steam part (at its presence) an upper feed for forming a distillation stream 37 that exits from the top of the column; and the lower section of the deprotanization 19b, which contains the plates and / or nozzle to provide the necessary contact between the liquids falling down and the vapors rising up. The depropanizer section 19b also includes one or more reboilers (such as reboiler 20) that heat and vaporize a portion of the liquid at the bottom of the column in order to create stripping vapors that extend up the column in order to drive the liquid product, stream 41, from methane and C ₂ components and C ₃ components. A typical technical characteristic for a bottom liquid product is a propane to butane ratio of 0.020: 1 based on volume. The liquid product stream 41 exits the bottom of the deethanizer at 286 ° E [141 ° C].

The upper distillation stream 37 exits the depropanizer 19 at 36 ° E [2 ° C] and is cooled and partially condensed with commercial grade propane refrigerant in the reflux condenser 21. The partially condensed stream 37a enters the reflux condenser 22 at 2 ° E [-17 ° C] where the condensed liquid (stream 44) is separated from non-condensed vapor (stream 43). The condensed liquid (stream 44) is pumped 23 to the upper feed point of the depropanizer 19 as a reflux stream 44a.

The non-condensed vapor (stream 43) from the reflux tank 22 is heated to 94 ° E [34 ° C] in the heat exchanger 24 and a part (stream 48) is then diverted for use as fuel gas in the installation. The remaining heated steam (stream 38) is compressed by compressor 16. After cooling to 100 ° E [38 ° C] from the cooler at outlet 25, stream 38b is cooled further to 15 ° E [-9 ° C] in the heat exchanger 24 by cross-exchange with cold ferry stream 43.

Stream 38c is then combined with intermediate pressure vapor from the separator (stream 42) to form a cold residual gas stream 49. Stream 49 enters heat exchanger 13 and is cooled from -38 ° E [-39 ° C] to -102 ° E [-74 ° C], liquids from the separator (streams 39a and 33a), as described previously, and through the flow of refrigerant 71e. The partially condensed stream 49a then enters the heat exchanger 60 and is further cooled by a refrigerant stream 716 to -254 ° E [-159 ° C] to condense and supercooled, after which it enters a working expansion machine 61, in which mechanical energy is extracted from the stream. In machine 61, fluid flow 49b expands substantially isentropically from a pressure of approximately 621 ry [4282 kPa (a)] to a storage pressure of LNG (15.5 mm [107 kPa (a)]), slightly above atmospheric pressure. The expansion operation cools the expanded stream 49c to a temperature of about -255 ° E [-159 ° C], after which it is then sent to the LNG storage tank 62, in which the LNG product is stored (stream 50).

Similarly to the methods of FIG. 1, 3 and 4, most of the cooling for stream 49 and all cooling for stream 49a is provided by a closed-loop cooling circuit. The composition of the stream used as the working fluid in the cycle for the method of FIG. 5 in approximate molar percent is 8.9% nitrogen, 34.3% methane, 41.3% ethane and 11.0% propane, with the remainder being heavier hydrocarbons. The refrigerant stream 71 leaves the cooler at outlet 69 at 100 ° E [38 ° C] and 607 rya [4185 kPa (a)]. It enters the heat exchanger 10 and is cooled to -30 ° E [-34 ° C] and partially condensed through a partially heated expanded refrigerant stream 71 потока and other refrigerant streams. To simulate FIG. 5 it has been suggested that these other refrigerant flows are commercial grade propane refrigerant at three different temperatures and pressures. The partially condensed refrigerant stream 71a then enters the heat exchanger 13 for further cooling to -102 ° E [-74 ° C] by means of a partially heated expanded refrigerant stream 71e and further condensation of the refrigerant (stream 71b). The refrigerant is completely condensed and then supercooled to -254 ° E [-159 ° C] in the heat exchanger 60 through an expanded refrigerant stream 716. The supercooled liquid stream 71c enters a working expansion machine 63, in which mechanical energy is extracted from the stream when it expands, essentially, isentropically from a pressure of about 586 mm [4040 kPa (a)] to about 34 roy [234 kPa (a)]. During expansion, part of the stream evaporates, as a result of which the entire stream is cooled to -264 ° E [-164 ° C] (stream 716). The expanded stream 716 is then returned to heat exchangers 60, 13 and 10, where it provides cooling for stream 49a, stream 49 and refrigerant (streams 71, 71a and 71b) when it evaporates and overheats.

Superheated refrigerant vapor (stream 71d) exits heat exchanger 10 at 93 ° E [34 ° C] and is compressed in three stages to 617 rya [4254 kPa (a)]. Each of the three compression stages (refrigerant compressors 64, 66 and 68) is driven by an additional energy source and is accompanied by a cooler (coolers at the outlet 65, 67 and 69) to remove the heat of compression. The compressed stream 71 from the cooler at the exit 69 is returned to the heat exchanger 10 to complete the cycle.

-12005326

The total flow rates and energy costs in the process shown in FIG. 4 are shown in the following table.

Table IV (Fig. 5)

Total flow rate - lb mol / h [kg mol / h]

Flow Methane Ethane Propane Bhutans + Total 31 40977 3861 2408 1404 48656 32 32360 2675 1469 701 37209 33 8617 1186 939 703 11447 38 13133 2513 1941 22 17610 39 6194 1648 1272 674 9788 41 0 0 22 1352 1375 42 26166 1027 197 27 27421 43 14811 2834 2189 25 19860 48 1678 321 248 3 2250 fifty 39299 3540 2138 2138 45031 Extracts in condensate* Bhutan 95.04% Pentanes + 99.57% Performance 88,390 lb / h [88390 kg / h]

LNG Product

834183 lb / h [834183 kg / h]

Performance

82.27%

Purity*

Lower calorific value

Ability

Energy wti / ssg [38.52 MJ / m ³ ]

Refrigerant compression

84,974 hp [139,696 kW]

Propane compression

39 439 hp

Total compression

124,413 hp [204,533 kW]

Heat used

Reboiler demethanizer

52913 ΜΒΤϋ / Ng [34182 kW] (Based on rounded flow rates)

Assuming that the performance indicator is 340 days per year for the LNG production facility, the specific energy consumption of FIG. 5 for the embodiment of the present invention is 0.145 hp-h / lb [0.238 kWh / kg]. Compared to prior art processes, the efficiency increase is 16-26% for the embodiment of FIG. 5.

Compared to the designs of FIG. 1 and 3, the embodiment of FIG. 5 of the present invention requires 5 to 10% less power per unit of fluid produced. Compared to the embodiment of FIG. 4, the embodiment of FIG. 5 of the present invention requires substantially the same capacity per unit of liquefied product. Thus, for a given amount of available compression power in the embodiment of FIG. 5 can liquefy about 5% more natural gas than in the embodiment of FIG. 1, about 10% more natural gas than in the embodiment of FIG. 3, or about the same amount of natural gas as in the embodiment of FIG. 4 by extracting only C ₄ and heavier hydrocarbons as a condensed by-product. The choice between the design of FIG. 5 in comparison with the designs or in FIG. 1, 3, or according to FIG. 4 of the present invention for a particular application will be mainly dictated either by the monetary value of ethane and propane, as part of the NGL or LPG product, compared to their corresponding value in the LNG product, or by the calorific value for the LNG product (since the calorific value of LNG produced through the design of Fig. 1, 3 and 4 lower than the calorific value of LNG produced by the design of Fig. 5).

Other designs

One of skill in the art will recognize that the present invention can be adapted for use with all types of LNG liquefaction plants to enable the production of as a by-product the PGC stream, LPG stream, or condensate stream that is best suited to the location requirements of this unit. In addition, it will be recognized that a variety of process configurations can be used to extract a liquid by-product stream. For example, the designs of FIG. 1 and 3 can be adapted to extract a LPG stream or a condensate stream as a liquid by-product stream, and not for an PGC stream, as described previously in Examples 1 and 2. The embodiment of FIG. 4 can be adjusted

-13005326 for extracting a PGC stream containing a significant fraction of the C ₂ components present in the feed gas, or for extracting a condensate stream containing only C ₄ and heavier components present in the feed gas, and not for producing a LPG by-product, as previously described for example 3. The design of FIG. 5 can be adapted to recover a PGC stream containing a significant fraction of the C ₂ component present in the feed gas, or to extract a LPG stream containing a significant fraction of the C ₃ components present in the feed gas, and not to produce a condensed by-product as described previously in example 4.

FIG. 1, 3, 4, and 5 represent preferred embodiments of the present invention for said processing conditions. In FIG. 6 to 21 depict alternative embodiments of the present invention that may be considered for a particular application. As shown in FIG. 6 and 7, all of the condensed liquid (stream 33), or part of it from the separator 11, can be fed into the distillation column 19 to a separate lower feed point in it in the middle of the column, rather than being combined with a part of the separated vapor (stream 34) passing into heat exchanger 13. FIG. 8 shows an alternative embodiment of the present invention, which requires less equipment than for the embodiments of FIG. 1 and 6, although the specific energy consumption in it is slightly higher. Similarly, in FIG. 9 shows an alternative embodiment of the present invention, which requires less equipment than for the embodiment of FIG. 3 and 7, also due to the higher specific energy consumption. FIG. 10 to 14 depict alternative designs of the present invention, which may require less equipment than the designs of FIG. 4, although the specific energy consumption in them may be higher. (Note that, as shown in FIGS. 10 to 14, distillation columns or systems, such as deethanizer 19, include both absorber column constructions with a reboiler and reboiler column constructions with reflux). In FIG. 15 and 16 show an alternative embodiment of the present invention, which combines the functions of the separator / absorber column 18 and deethanizer 19 in the embodiments of FIG. 4 and from 10 to 14 in one distillation column 19. Depending on the amount of heavier hydrocarbons in the feed gas and the pressure of the feed gas, the cooled feed stream 31a leaving the heat exchanger 10 may not contain liquid at all, since it is above the dew point, or because it is above its cricondenbar, so that the separator 11 shown in FIG. 1 and from 3 to 16 is not required, and the cooled feed stream can pass directly to a suitable expansion device, such as a working expansion machine 15.

The location of the gas stream remaining after the extraction of the liquid by-product stream (stream 37 in Figs. 1, 3 and 6 to 11, 13 and 14, stream 47 in Figs. 4, 12, 15 and 16 and stream 43 in Fig. 5) before applying it to the heat exchanger 60 for condensation and subcooling, can be performed in many ways. In the methods of FIG. 1 and from 3 to 16, the flow is heated, compressed to a higher pressure using energy extracted from one or more working expansion machines, partially cooled in the outlet cooler, then further cooled by transverse heat exchange with the original stream. As shown in FIG. 17, in some applications it may be useful to compress the flow to a higher pressure using an auxiliary compressor 59, which is driven by an external energy source, for example. As shown by the dotted equipment (heat exchanger 24 and outlet cooler 25) in FIG. 1 and from 3 to 16, a number of circumstances can be useful by reducing the capital cost of equipment by reducing or eliminating the preliminary cooling of the compressed stream before it enters the heat exchanger 60 (due to an increase in the cooling load on the heat exchanger 60 and an increase in the energy cost of refrigerant compressors 64, 66 and 68). In such cases, the stream 49a exiting the compressor can flow directly into the heat exchanger 24, as shown in FIG. 18, or pass directly into the heat exchanger 60, as shown in FIG. 19. If working expansion machines are not used to expand any part of the high pressure feed gas, a compressor that is driven by an external energy source, such as the compressor 59 shown in FIG. 20 may be used in place of compressor 16. In other circumstances, the compression of the flow may not be controlled at all, so that the flow passes directly to the heat exchanger 60, as shown in FIG. 21, and by means of the dotted equipment (heat exchanger 24, compressor 16 and cooler at outlet 25) in FIG. 1 and 3 to 16. If the heat exchanger 24 is not turned on to heat the stream before the unit’s fuel gas is exhausted (stream 48), an additional heater 58 may be required to heat the fuel gas before it is used up, using a utilized stream or another process stream to supply the necessary heat, as shown in FIG. 19 to 21. Variants such as these should generally be evaluated for each application, with factors such as gas composition, installation size, required amount of by-product stream extracted, and disposable equipment being taken into account.

-14005326

In accordance with the present invention, the cooling of the inlet gas stream and the feed stream to the LNG production section can be accomplished in many ways. In the processes of FIG. 1, 3 and from 6 to 9, the incoming gas stream 31 is cooled and condensed by external refrigerant streams and liquids from the distillation column 19. In FIG. 4, 5 and 10 to 14 liquids from the flash separator are used for this purpose together with external refrigerant flows. In FIG. 15 and 16 liquids from the column and liquids from the flash separator are used for this purpose together with external refrigerant flows. And in FIG. 17 to 21, only external refrigerant flows are used to cool the inlet gas stream 31. However, cold process streams can also be used to supply some cooling to a high pressure refrigerant (stream 71a), such as that shown in FIG. 4, 5, 10 and 11. In addition, any stream at a temperature colder than the stream (s) to be cooled can be used. For example, the lateral steam outlet from the separator / absorber column 18 or distillation column 19 may be diverted and used for cooling. The use and distribution of liquids and / or vapors of a column for a heat transfer process and the specific arrangement of heat exchangers for cooling the inlet gas and feed gas can be evaluated for each specific application, as well as the choice of process streams for specific heat transfer purposes. The choice of a cooling source will depend on a number of factors, including, but not limited to, the composition and conditions of the gas supplied, the size of the heat exchanger, the potential temperature of the cooling source, etc. One of ordinary skill in the art will also find that any combination of the above cooling sources or cooling methods can be applied in combination in order to achieve the desired temperature of the feed stream.

In addition, additional external cooling, which is supplied to the inlet gas stream and the feed stream to the LNG production section, can also be performed in many different ways. In FIG. 1 and from 3 to 21, a boiling single-component refrigerant was adopted for high-level external cooling, and an evaporating multi-component refrigerant was adopted for low-level external cooling, wherein a single-component refrigerant was adopted for pre-cooling of the multi-component refrigerant. Alternatively, both high-level cooling and low-level cooling can be performed using single-component refrigerants with successively lower boiling points (ie, "cascade cooling"), or one single-component refrigerant at successively lower evaporation pressures. As another alternative, both high level cooling and low level cooling can be performed using multicomponent refrigerant streams with their respective compositions adjusted to provide the required cooling temperatures. The choice of method for providing external cooling will depend on a number of factors, including, but not limited to, the composition and conditions of the supplied gas, installation size, compressor drive size, heat exchanger size, ambient temperature of the heat receiver, etc. One of ordinary skill in the art will also find that any combination of the methods for producing external cooling described above can be applied in combination in order to obtain the desired temperature of the feed stream.

Subcooling of the condensed liquid stream leaving the heat exchanger 60 (stream 49 in FIGS. 1, 6 and 8, stream 496 in FIGS. 3, 4, 7 and 9 to 16, stream 49b in FIGS. 5, 19 and 20, stream 49e in Fig. 17, stream 49c in Fig. 18 and stream 49a in Fig. 21) reduces or eliminates the amount of flash vapor that can be generated during expansion of the stream to operating pressure in the LNG storage tank 62. This mainly reduces the specific energy consumption for LNG production by eliminating the need for compression of instantly evaporated gas. However, in some circumstances, it may be useful to reduce the capital cost of the equipment by reducing the size of the heat exchanger 60 and using compression of flash gas or other means to place any flash gas that can be generated.

Although expansion of a single stream is depicted in specific expansion devices, alternative expansion means may be used if appropriate. For example, conditions can guarantee the operation of expansion of a substantially condensed feed stream (stream 35a in FIGS. 1, 3, 6, and 7) or a reflux stream at intermediate pressure (stream 39 in FIGS. 1, 6, and 8). In addition, isentalpic expansion during flash evaporation can be used instead of the expansion operation for the supercooled liquid stream leaving the heat exchanger 60 (stream 49 in FIGS. 1, 6 and 8, stream 496 in FIGS. 3, 4, 7 and from 9 to 16 , stream 49b in Fig. 5, 19 and 20, stream 49e in Fig. 17, stream 49c in Fig. 18 and stream 49a in Fig. 21), but either more subcooling in the heat exchanger 60 will be necessary to prevent instant evaporation of steam during expansion, or additional compression of flash vapor, or other means for placing the floor aemogo resulting flash vapor. Similarly, isentalpic expansion during flash evaporation can be used instead of expansion work for the supercooled high-pressure refrigerant stream exiting the heat exchanger 60 (stream 71c in FIG. 1 and 3 to 21), resulting in increased energy costs for compressing the refrigerant.

-15005326

In the description of the alleged preferred embodiments of the invention, those skilled in the art will find that other and further modifications can be made therein, for example, adapting the invention to a variety of conditions, types of delivery or other requirements without departing from the spirit of the present invention, as defined the following claims.

Claims (116)

CLAIM (1) one or more second heat transfer means interconnected to receive a natural gas stream and cool it under pressure; 1. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages; (2) compression means connected to heating means in order to receive the heated volatile fraction of the residual gas and compress it; and (3) a first heat exchange means connected to the compression means in order to receive a compressed heated volatile fraction of the residual gas, the first heat exchange means adapted to cool the compressed heated volatile fraction of the residual gas under pressure in order to condense at least part of it and thus form a condensed stream. (2) compression means connected to heating means in order to receive the heated volatile fraction of the residual gas and compress it; and (3) a first heat exchange means connected to the compression means in order to receive a compressed heated volatile fraction of the residual gas, the first heat exchange means adapted to cool the compressed heated volatile fraction of the residual gas under pressure in order to condense at least part of it and thus form a condensed stream. (2) compression means connected to heating means in order to receive a heated, more volatile stream of distillation steam and compress it; (2) compression means connected to heating means in order to receive a heated, more volatile stream of distillation steam and compress it; (2) compression means connected to heating means in order to receive the heated volatile fraction of the residual gas and compress it; (2) compression means connected to heating means in order to receive the heated volatile fraction of the residual gas and compress it; (2) compression means connected to heating means in order to receive the heated volatile fraction of the residual gas and compress it; (2) compression means connected to heating means in order to receive the heated volatile fraction of the residual gas and compress it; (2) compression means connected to heating means in order to receive the heated volatile fraction of the residual gas and compress it; and (3) a first heat exchange means connected to the compression means in order to receive a compressed heated volatile fraction of the residual gas, the first heat exchange means adapted to cool the compressed volatile fraction of the residual gas under pressure in order to condense at least a part of it and thus form a condensed stream. (2) a first heat transfer means connected to a compression means in order to receive a compressed volatile fraction of the residual gas, the first heat exchange means being adapted -47005326 leno in order to cool the compressed volatile fraction of the residual gas under pressure in order to condense at least part of it; and (3) a second separation means connected to the first heat exchange means in order to receive the condensed part and divide it into at least two parts, thereby forming a condensed stream and a second liquid stream, wherein the second separation means is further connected to the distillation column in order to direct a second liquid stream into the distillation column with a feed to it from above. (2) a first heat exchange means connected to a compression means to receive a compressed volatile fraction of the residual gas, the first heat exchange means adapted to cool the compressed volatile fraction of the residual gas under pressure in order to condense at least its part; and (3) a second separation means connected to the first heat exchange means in order to receive the condensed part and divide it into at least two parts, thereby forming a condensed stream and a liquid stream, wherein the second separation means is further connected with a distillation column in order to direct the flow of liquid into the distillation column with a feed into it from above. (2) a first heat exchange means connected to a compression means to receive a compressed volatile fraction of the residual gas, the first heat exchange means adapted to cool the compressed volatile fraction of the residual gas under pressure in order to condense at least its part; and (3) a separation means connected to the first heat exchange means in order to receive the condensed part and divide it into at least two parts, thereby forming a condensed stream and a second liquid stream, wherein the separation means is further connected to the distillation column in order to direct the second fluid stream into the distillation column with a feed into it from above. (2) a first heat exchange means connected to a compression means to receive a compressed volatile fraction of the residual gas, the first heat exchange means adapted to cool the compressed volatile fraction of the residual gas under pressure in order to condense at least its part; and (3) a separation means connected to the first heat exchange means in order to receive the condensed part and divide it into at least two parts, thereby forming a condensed stream and a liquid stream, wherein the separation means is further connected to the distillation column in order to direct the flow of liquid into the distillation column with a feed into it from above. (2) a second separation means connected to the second heat exchange means in order to receive a partially condensed natural gas stream and to separate it into a steam stream and a liquid stream; (2) a second expansion means connected to the second heat exchange means in order to receive a cooled stream of natural gas and expand it to an intermediate pressure; (2) a first separation means connected to a second heat exchange means in order to receive a partially condensed natural gas stream and to separate it into a first vapor stream and a first liquid stream; (2) a second expansion means connected to the second heat exchange means in order to receive a cooled stream of natural gas and expand it to an intermediate pressure; (2) a first separation means connected to a second heat exchange means in order to receive a partially condensed natural gas stream and to separate it into a first vapor stream and a first liquid stream; (2) a second expansion means connected to the second heat exchange means in order to receive a cooled stream of natural gas and expand it to an intermediate pressure; (2) a first separation means connected to a second heat exchange means in order to receive a partially condensed natural gas stream and to separate it into a first vapor stream and a first liquid stream; (2) a second expansion means connected to the second heat exchange means in order to receive a cooled stream of natural gas and expand it to an intermediate pressure; (2) a first separation means connected to a second heat exchange means in order to receive a partially condensed natural gas stream and to separate it into a first vapor stream and a first liquid stream; (2) a second expansion means connected to the second heat exchange means in order to receive a cooled stream of natural gas and expand it to an intermediate pressure; (2) a first separation means connected to a second heat exchange means in order to receive a partially condensed natural gas stream and to separate it into a first vapor stream and a first liquid stream; (2) a second expansion means connected to the second heat exchange means in order to receive a cooled stream of natural gas and expand it to an intermediate pressure; (2) a separation means connected to a second heat exchange means in order to receive a partially condensed stream of natural gas and separate it into a first vapor stream and a first liquid stream; (2) a second expansion means connected to the second heat exchange means in order to receive a cooled stream of natural gas and expand it to an intermediate pressure; -36005326 (3) contacting and separating means connected to receive an expanded cooled stream of natural gas, said contacting and separating means comprising at least one contacting device for mixing liquid and steam, and includes means for separation in order to separate the vapor and liquid after mixing in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components, and a first liquid stream; (2) a first separation means connected to a second heat exchange means in order to receive a partially condensed natural gas stream and to separate it into a first vapor stream and a first liquid stream; (2) second expansion means coupled to heat exchange means in order to receive a cooled stream of natural gas and expand it to an intermediate pressure; (2) a separation means connected to a second heat exchange means in order to receive a partially condensed natural gas stream and to separate it into a steam stream and a first liquid stream; (2) a second expansion means connected to the second heat exchange means in order to receive a cooled stream of natural gas and expand it to an intermediate pressure; (2) a first separation means connected to a second heat exchange means in order to receive a partially condensed natural gas stream and to separate it into a first vapor stream and a first liquid stream; (2) a second expansion means connected to the second heat exchange means in order to receive a cooled stream of natural gas and expand it to an intermediate pressure; (2) a separation means connected to a second heat exchange means in order to receive a partially condensed natural gas stream and to separate it into a steam stream and a first liquid stream; -31005326 (3) first separation means connected to separation means in order to receive a steam stream and separate it into at least a first gaseous stream and a second gaseous stream; (2) a separation means connected to a second heat exchange means in order to receive a partially condensed natural gas stream and to separate it into a steam stream and a first liquid stream; (2) a first separation means coupled to a second heat exchange means in order to receive a cooled natural gas stream and separate it into at least a first gaseous stream and a second gaseous stream; (2) a separation means connected to the second heat exchange means in order to receive a partially condensed natural gas stream and to separate it into a steam stream and a liquid stream; (2) a separation means connected to a second heat exchange means in order to receive a partially condensed natural gas stream and to separate it into a steam stream and a first liquid stream; (2) a separation means connected to a second heat exchange means in order to receive a cooled natural gas stream and separate it into a first gaseous stream and a second gaseous stream; (2) a separation means connected to a second heat exchange means in order to receive a partially condensed natural gas stream and to separate it into a steam stream and a first liquid stream; (2) a second expansion means connected to the second heat exchange means in order to receive a cooled stream of natural gas and expand it to an intermediate pressure; (2) the partially condensed natural gas stream is separated so as to create at least a vapor stream and a liquid stream; (2) the cooled natural gas stream is expanded to an intermediate pressure; (2) the partially condensed natural gas stream is separated so as to form a first vapor stream and a first liquid stream; (2) the cooled natural gas stream is expanded to an intermediate pressure and then directed to the middle of the column at the feed point to the distillation column, in which said stream is separated into a more volatile steam distillation stream and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (2) the partially condensed natural gas stream is separated so as to create a first vapor stream and a first liquid stream; (2) the cooled natural gas stream is expanded to an intermediate pressure and then directed to the middle of the column to the feed point to the distillation column, in which these streams are separated into a more volatile steam distillation stream and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (2) the partially condensed natural gas stream is separated so as to create a first vapor stream and a first liquid stream; (2) the cooled natural gas stream is expanded to an intermediate pressure and then directed to the middle of the column at the feed point to the distillation column, in which said stream is separated into a more volatile steam distillation stream and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (2) the partially condensed natural gas stream is separated so as to create a first vapor stream and a first liquid stream; (2) the cooled natural gas stream is expanded to an intermediate pressure and thereafter sent to the middle of the column at the feed point to the distillation column in which said sep stream -22005326 are converted to a more volatile stream of steam distillation and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (2) the partially condensed natural gas stream is separated so as to create a first vapor stream and a first liquid stream; (2) the cooled natural gas stream is expanded to an intermediate pressure and then sent to the contacting device, thereby forming a first vapor stream and a first liquid stream; (2) the partially condensed natural gas stream is separated so as to create a steam stream and a first liquid stream; (2) the cooled natural gas stream is expanded to an intermediate pressure and then sent to a contacting device, thereby forming a volatile fraction of the residual gas containing the bulk of methane and lighter components, and a first liquid stream; (2) the partially condensed natural gas stream is separated so as to create a first vapor stream and a first liquid stream; (2) the cooled natural gas stream is expanded to an intermediate pressure and then sent to the contacting device, thereby forming a first vapor stream and a first liquid stream; (2) the partially condensed natural gas stream is separated so as to create a steam stream and a first liquid stream; (2) the cooled natural gas stream is expanded to an intermediate pressure and then sent to a contacting device, thereby forming a volatile fraction of the residual gas containing the bulk of methane and lighter components, and a first liquid stream; -19005326 (3) a first liquid stream is sent to a distillation column in which said stream is separated into a more volatile stream of distillation steam and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (2) the partially condensed natural gas stream is separated so as to create a first vapor stream and a first liquid stream; (2) the chilled natural gas stream is expanded to an intermediate pressure; (2) the partially condensed natural gas stream is separated so as to create a steam stream and a first liquid stream; (2) the partially condensed natural gas stream is separated so as to create a steam stream and a first liquid stream; (2) the cooled natural gas stream is separated into at least a first gaseous stream and a second gaseous stream; -17005326 (3) the first gaseous stream is cooled in order to condense it substantially completely and then expand to an intermediate pressure; (2) the partially condensed natural gas stream is separated so as to create a vapor stream and a liquid stream; (2) the partially condensed natural gas stream is separated so as to create a vapor stream and a liquid stream; (2) the chilled natural gas stream is separated into at least a first gaseous stream and a second gaseous stream; (2) the partially condensed natural gas stream is separated so as to create at least a vapor stream and a first liquid stream; 2. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion thereof and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; wherein (1) the natural gas stream is treated in one or more cooling steps in order to partially condense it; (2) the chilled natural gas stream is expanded to an intermediate pressure; (3) cooling means coupled to the compression means in order to receive a compressed heated more volatile stream of distillation steam and cool it; (3) cooling means coupled to the compression means in order to receive a compressed heated more volatile stream of distillation steam and cool it; (3) a first heat exchange means connected to the compression means in order to receive a compressed heated volatile fraction of the residual gas, the first heat exchange means adapted to cool the compressed heated volatile fraction of the residual gas under pressure in order to condense at least part of it; and (4) a second separation means connected to the first heat exchange means in order to receive the condensed part and divide it into at least two parts, thereby forming a condensed stream and a second liquid stream, wherein the second separation means is further connected to the distillation column in order to direct a second liquid stream into the distillation column with a feed to it from above. (3) a first heat exchange means connected to the compression means in order to receive a compressed heated volatile fraction of the residual gas, the first heat exchange means adapted to cool the compressed heated volatile fraction of the residual gas under pressure in order to condense at least part of it; and (4) a second separation means connected to the first heat exchange means in order to receive the condensed part and divide it into at least two parts, thereby forming a condensed stream and a liquid stream, wherein the second separation means is further connected with a distillation column in order to direct the flow of liquid into the distillation column with a feed into it from above. (3) a first heat exchange means connected to the compression means in order to receive a compressed heated volatile fraction of the residual gas, the first heat exchange means adapted to cool the compressed heated volatile fraction of the residual gas under pressure in order to condense at least part of it; and (4) a separation means connected to the first heat exchange means in order to receive the condensed part and divide it into at least two parts, thereby forming a condensed stream and a second liquid stream, wherein the separation means is further connected to distillation column in order to direct the second fluid flow into the distillation column with the flow into it from above. (3) a first heat exchange means connected to the compression means in order to receive a compressed heated volatile fraction of the residual gas, the first heat exchange means adapted to cool the compressed heated volatile fraction of the residual gas under pressure in order to condense at least part of it; and (4) a separation means connected to the first heat exchange means in order to receive the condensed part and divide it into at least two parts, thereby forming a condensed stream and a liquid stream, wherein the separation means is further connected to the distillation column in order to direct the flow of liquid into the distillation column with a feed into it from above. (3) second expansion means connected to the separation means in order to receive the steam stream and expand it to an intermediate pressure; (3) a distillation column connected to receive an expanded cooled stream of natural gas, the distillation column being adapted to separate said stream into a volatile fraction of the residual gas containing the bulk of methane and lighter components and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (3) second expansion means coupled to the first separation means in order to receive the first vapor stream and expand it to an intermediate pressure; (3) a distillation column connected to receive an expanded cooled stream of natural gas, the distillation column being adapted to separate the stream into a more volatile stream of distillation steam and a relatively less volatile fraction containing most of the heavier hydrocarbon components; (3) second expansion means coupled to the first separation means in order to receive the first vapor stream and expand it to an intermediate pressure; (3) a distillation column connected to receive an expanded cooled natural gas stream, the distillation column being adapted to separate said stream into a more volatile distillation vapor stream and a relatively less volatile fraction containing a majority of the heavier hydrocarbon components; (3) second expansion means coupled to the first separation means in order to receive the first vapor stream and expand it to an intermediate pressure; (3) a distillation column connected to receive an expanded cooled stream of natural gas, the distillation column being adapted to separate the stream into a more volatile stream of distillation steam and a relatively less volatile fraction containing most of the heavier hydrocarbon components; (3) second expansion means coupled to the first separation means in order to receive the first vapor stream and expand it to an intermediate pressure; (3) a distillation column connected to receive an expanded cooled natural gas stream, the distillation column being adapted to separate said stream into a more volatile distillation vapor stream and a relatively less volatile fraction containing a majority of the heavier hydrocarbon components; (3) second expansion means coupled to the first separation means in order to receive the first vapor stream and expand it to an intermediate pressure; (3) contacting and separating means connected to receive an expanded cooled stream of natural gas, said contacting and separating means comprising at least one contacting means for mixing liquid and steam, and including means for separating for in order to separate steam and liquid after mixing in order to form a first vapor stream and a first liquid stream; (3) second expansion means connected to the separation means in order to receive the first vapor stream and expand it to an intermediate pressure; (3) second expansion means coupled to the first separation means in order to receive the first vapor stream and expand it to an intermediate pressure; (3) contacting and separating means connected to receive an expanded stream of chilled natural gas, said contacting and separating means comprising at least one contacting means for mixing liquid and steam, and including means for separating for in order to separate steam and liquid after mixing in order to form a first vapor stream and a first liquid stream; (3) second expansion means connected to the separation means in order to receive the steam stream and expand it to an intermediate pressure; (3) a means for contacting and separating, connected in order to receive an expanded cooled stream of natural gas, and the means for contacting and separation contains -33005326 at least one contacting device for mixing liquid and steam, and includes separation means for separating steam and liquid after mixing in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components, and a first fluid stream; (3) second expansion means connected to the first separation means in order to receive the expanded first vapor stream and expand it to an intermediate pressure; (3) a separation means connected to the second expansion means in order to receive the expanded cooled natural gas stream and separate it into a steam stream and a liquid stream; (3) first separation means connected to separation means in order to receive a steam stream and separate it into at least a first gaseous stream and a second gaseous stream; (3) a third heat exchange means connected to the first separation means in order to receive the first gaseous stream and cool it sufficiently to substantially condense it; (3) a separation means connected to the separation means in order to receive a steam stream and separate it into at least a first gaseous stream and a second gaseous stream; (3) a separation means connected to the separation means in order to receive a steam stream and separate it into at least a first gaseous stream and a second gaseous stream; (3) a third heat transfer means coupled to the separation means in order to receive the first gaseous stream and cool it sufficiently to substantially condense it; (3) second expansion means connected to the separation means in order to receive the steam stream and expand it to an intermediate pressure; (3) a distillation column connected in order to receive an expanded cooled natural gas stream, said distillation column being adapted to separate said stream into a volatile fraction of the residual gas containing the bulk of methane and lighter components and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (3) the steam stream is expanded to an intermediate pressure; (3) the expanded cooled natural gas stream is sent to a distillation column in which said stream is separated into a volatile fraction of the residual gas containing the bulk of methane and lighter components and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; and (4) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (3) a first vapor stream and a first liquid stream expand to an intermediate pressure; (3) the distillation steam stream is diverted from the distillation column section below the expanded cooled natural gas stream and is cooled sufficiently to condense at least a portion thereof, thereby forming a vapor stream and a liquid stream; (3) a first vapor stream and a first liquid stream expand to an intermediate pressure; (3) the distillation steam stream is diverted from the distillation column section below the expanded cooled natural gas stream and is cooled sufficiently to condense at least a portion thereof, thereby forming a vapor stream and a liquid stream; (3) a first vapor stream and a first liquid stream expand to an intermediate pressure; (3) the distillation steam stream is diverted from the distillation column section below the expanded cooled natural gas stream and is cooled sufficiently to condense at least a portion thereof, thereby forming a vapor stream and a liquid stream; (3) a first vapor stream and a first liquid stream expand to an intermediate pressure; (3) the distillation steam stream is diverted from the distillation column section below the expanded cooled natural gas stream and is cooled sufficiently to condense at least a portion thereof, thereby forming a vapor stream and a liquid stream; (3) the first vapor stream is expanded to an intermediate pressure and then sent to the contacting device, thereby forming a second vapor stream and a second liquid stream; (3) the first liquid stream is heated and then sent to a distillation column in which said stream is separated into a more volatile stream of distillation steam and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (3) the steam stream is expanded to an intermediate pressure and then sent to the contacting device, thereby forming a volatile fraction of the residual gas containing the bulk of methane and lighter hydrocarbon components, and a second liquid stream; (3) the first liquid stream is heated and then sent to a distillation column in which said stream is separated into a more volatile stream of distillation steam and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (3) the first vapor stream is expanded to an intermediate pressure and then sent to the contacting device, thereby forming a second vapor stream and a second liquid stream; (3) a first liquid stream is sent to a distillation column in which said stream is separated into a more volatile stream of distillation steam and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (3) the steam stream is expanded to an intermediate pressure and then sent to the contacting device, thereby forming a volatile fraction of the residual gas containing the bulk of methane and lighter components, and a second liquid stream; (3) the first steam stream is expanded to an intermediate pressure; (3) the expanded cooled natural gas stream is separated so as to create a vapor stream and a liquid stream; (3) the vapor stream is separated into at least a first gaseous stream and a second gaseous stream; (3) the vapor stream is separated into at least a first gaseous stream and a second gaseous stream; (3) the vapor stream is separated into at least a first gaseous stream and a second gaseous stream; (3) the vapor stream is separated into at least a first gaseous stream and a second gaseous stream; (3) the first gaseous stream is cooled in order to condense it substantially completely, and then expand to an intermediate pressure; 3. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion thereof and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages; (3) the steam stream is expanded to an intermediate pressure; (3) the chilled natural gas stream is sent to a distillation column in which said stream is separated into a volatile fraction of the residual gas containing the bulk of methane and lighter components, and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (4) combining means connected to a second separation means and cooling means in order to receive a second steam stream and a cooled compressed more volatile stream -49005326 steam distillation and combine them in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components. (4) a combining means coupled to a separating means and a cooling means to receive a steam stream and a cooled compressed more volatile distillation steam stream and combine them to form a volatile residual gas fraction containing a majority of methane and more light components. (4) a third expansion means connected to the separation means in order to receive a fluid stream and expand it to a specified intermediate pressure; -46005326 (5) a distillation column connected to receive an expanded vapor stream and an expanded liquid stream, the distillation column being adapted to separate said streams into a volatile fraction of the residual gas containing the bulk of methane and lighter components, and relatively a smaller volatile fraction containing the bulk of the heavier hydrocarbon components; (4) a first heat exchange means connected to the distillation column in order to receive a volatile fraction of the residual gas, the first heat exchange means adapted to cool the volatile fraction of the residual gas under pressure to condense at least a portion thereof and form, thus a condensed stream; and (5) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature at the top of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (4) third expansion means connected to the first separation means in order to receive the first fluid stream and expand it to an intermediate pressure; (4) steam venting means connected to the distillation column in order to receive a distillation steam stream from a portion of this distillation column below an expanded cooled natural gas stream; (4) a third expansion means connected to the first separation means in order to receive the first liquid stream and expand it to the specified intermediate pressure; (4) steam venting means connected to the distillation column in order to receive a distillation steam stream from the distillation column section below the expanded cooled natural gas stream; (4) a third expansion means connected to the first separation means in order to receive the first liquid stream and expand it to the specified intermediate pressure; (4) steam venting means connected to the distillation column in order to receive a distillation steam stream from the distillation column section below the expanded cooled natural gas stream; (4) a third expansion means connected to the first separation means in order to receive the first liquid stream and expand it to the specified intermediate pressure; (4) steam venting means connected to the distillation column in order to receive a distillation steam stream from the distillation column section below the expanded cooled natural gas stream; (4) contacting and separating means connected to receive an expanded first vapor stream, said contacting and separating means comprising at least one contacting device in order to mix liquid and steam, and including a separation means for to separate steam and liquid after mixing in order to form a second vapor stream and a second liquid stream; (4) a third heat transfer means connected to the contacting and separation means in order to receive the first fluid stream and heat it; (4) contacting and separating means connected to receive an expanded first vapor stream, said contacting and separating means comprising at least one contacting device in order to mix liquid and steam, and including a separation means for to separate the vapor and liquid after mixing in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components, and a second liquid stream; (4) a third heat transfer means connected to the contacting and separation means in order to receive the first fluid stream and heat it; (4) contacting and separating means connected to receive an expanded first vapor stream, said contacting and separating means comprising at least one contacting device in order to mix liquid and steam, and including a separation means for to separate steam and liquid after mixing in order to form a second vapor stream and a second liquid stream; (4) a distillation column connected to receive a first liquid stream, wherein the distillation column is adapted to separate said stream into a more volatile distillation vapor stream and a relatively less volatile fraction containing a majority of the heavier hydrocarbon components; (4) contacting and separating means connected in order to receive an expanded steam stream, said contacting and separating means comprising at least one contacting device in order to mix liquid and steam, and including a separation means for to separate the vapor and liquid after mixing in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components, and a second liquid stream; (4) a distillation column connected to receive a first liquid stream, wherein the distillation column is adapted to separate said stream into a more volatile distillation vapor stream and a relatively less volatile fraction containing a majority of the heavier hydrocarbon components; (4) second separation means connected to second expansion means in order to receive the expanded first steam stream and separate it into a second steam stream and a second liquid stream; (4) a third expansion means connected to the separation means in order to receive a fluid stream and expand it to a lower intermediate pressure; (4) combining means connected to the first separating means and to the separating means in order to receive the first gaseous stream and at least a portion of the liquid stream, and to combine them into a combined stream; (4) a third heat exchange means connected to the first separation means in order to receive the first gaseous stream and cool it sufficiently to partially condense it; (4) a second expansion means connected to a third heat exchange means in order to receive a substantially condensed first gaseous stream and expand it to an intermediate pressure; (4) combining means connected to separation means and to separation means in order to receive a first gaseous stream and at least a portion of a liquid stream and combine them into a combined stream; -29005326 (5) a third heat exchange means connected to the combination means in order to receive the combined stream and cool it sufficiently to substantially condense it; (4) a third heat transfer means coupled to the separation means in order to receive the first gaseous stream and cool it sufficiently to substantially condense it; (4) a second expansion means connected to a third heat exchange means in order to receive a substantially condensed first gaseous stream and expand it to an intermediate pressure; (4) a third expansion means connected to the separation means in order to receive the first fluid stream and expand it to the specified intermediate pressure; (4) a first heat transfer means connected to the distillation column in order to receive a volatile fraction of the residual gas, the first heat exchange means adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof; (4) the fluid flow is expanded to the specified intermediate pressure; (4) the expanded first steam stream and the expanded first liquid stream are sent to the middle of the column to the feed points to the distillation column, in which these streams are separated into a more volatile steam distillation stream and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (4) a portion of the liquid stream is supplied to the distillation column, as another feed thereto, to a supply point, essentially in the same section from which the distillation steam stream is diverted; (4) the expanded first steam stream and the expanded first liquid stream are sent to the middle of the column to the feed points to the distillation column, in which these streams are separated into a more volatile steam distillation stream and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; -24005326 (5) the distillation steam stream is diverted from the distillation column section below the expanded first vapor stream and cooled sufficiently to condense at least a portion thereof, thereby forming a second vapor stream and a second liquid stream; (4) at least a portion of the expanded cooled natural gas stream is brought into intimate contact with at least a portion of the liquid stream in the distillation column; (4) the expanded first steam stream and the expanded first liquid stream are sent to the middle of the column to the feed points to the distillation column, in which these streams are separated into a more volatile steam distillation stream and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (4) a portion of the liquid stream is supplied to the distillation column, as another feed thereto, to a supply point, essentially in the same section from which the distillation steam stream is taken off; (4) the expanded first vapor stream and the expanded first liquid stream are sent to the middle of the column to the feed points to the distillation column, in which the streams are separated into a more volatile steam distillation stream and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (4) at least a portion of the expanded cooled natural gas stream is brought into intimate contact with at least a portion of the liquid stream in the distillation column; (4) a second fluid stream is heated; (4) a more volatile vapor distillation stream is cooled sufficiently to condense at least a portion thereof, thereby forming a second vapor stream and a second liquid stream; (4) a second fluid stream is heated; (4) a more volatile vapor distillation stream is cooled sufficiently to condense at least a portion thereof, thereby forming a second liquid stream; (4) the first fluid stream is expanded to a specified intermediate pressure; (4) a more volatile steam distillation stream is cooled sufficiently to condense at least a portion of it, thereby forming a second vapor stream and a second liquid stream; (4) the first fluid stream is expanded to an intermediate pressure; (4) a more volatile vapor distillation stream is cooled sufficiently to condense at least a portion thereof, thereby forming a second liquid stream; (4) the expanded first vapor stream is separated in order to thereby create a second vapor stream and a second liquid stream; (4) the fluid flow is expanded to a lower intermediate pressure; (4) the first gaseous stream is combined with at least a portion of the first liquid stream, thereby forming a combined stream; (4) the first gaseous stream is cooled in order to condense it substantially completely and then expanded to an intermediate pressure; (4) the second gaseous stream is expanded to the specified intermediate pressure; (4) the first gaseous stream is combined with at least a portion of the liquid stream, thereby forming a combined stream; (4) the first gaseous stream is cooled in order to condense it substantially completely and then expand to an intermediate pressure; 4. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; wherein (1) the natural gas stream is processed in one or more cooling stages in order to partially condense it; (4) the second gaseous stream is expanded to the specified intermediate pressure; (4) the first fluid stream is expanded to a specified intermediate pressure; (4) said volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion thereof; (5) a distillation column connected to receive an expanded first vapor stream and an expanded first liquid stream, wherein the distillation column is adapted to separate said streams into a more volatile distillation vapor stream and a relatively less volatile fraction containing a majority of the heavier hydrocarbon components; (5) a third heat transfer means coupled to the steam removal means in order to receive said distillation steam stream and cool it sufficiently to condense at least a portion thereof; (5) a distillation column connected to receive an expanded first vapor stream and an expanded first liquid stream, wherein the distillation column is adapted to -43005326 fend off these streams with a more volatile steam distillation stream and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (5) a third heat transfer means coupled to the steam exhaust means in order to receive a steam stream of distillation and cool it sufficiently to condense at least a portion thereof; (5) a distillation column connected to receive an expanded first vapor stream and an expanded first liquid stream, wherein the distillation column is adapted to separate the streams into a more volatile distillation vapor stream and a relatively less volatile fraction containing a majority of the heavier components hydrocarbons; (5) a third heat transfer means coupled to the steam exhaust means in order to receive a steam stream of distillation and cool it sufficiently to condense at least a portion thereof; (5) a distillation column connected to receive an expanded first vapor stream and an expanded first liquid stream, wherein the distillation column is adapted to separate said streams into a more volatile distillation vapor stream and a relatively less volatile fraction containing a majority of the heavier hydrocarbon components; (5) a third heat transfer means coupled to the steam exhaust means in order to receive a steam stream of distillation and cool it sufficiently to condense at least a portion thereof; (5) a third heat transfer means connected to the contacting and separation means in order to receive a second fluid stream and heat it; (5) a distillation column connected to receive a heated first liquid stream, the distillation column being adapted to separate said stream into a more volatile stream of distillation steam and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (5) a third heat transfer means connected to the contacting and separation means in order to receive the first fluid stream and heat it; (5) a distillation column connected to receive a heated first liquid stream, the distillation column being adapted to separate said stream into a more volatile stream of distillation steam and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (5) a third expansion means connected to the separation means in order to receive the first fluid stream and expand it to the specified intermediate pressure; (5) a third heat transfer means connected to the distillation column in order to receive a more volatile stream of distillation steam and cool it enough to condense at least a portion thereof; (5) a third expansion means connected to the separation means in order to receive the first fluid stream and expand it to the specified intermediate pressure; (5) a third heat transfer means connected to the distillation column in order to receive a more volatile stream of distillation steam and cool it enough to condense at least a portion thereof, thereby forming a second liquid stream; (5) a third expansion means connected to the second separation means in order to receive a second fluid stream and expand it to a lower intermediate pressure; (5) a distillation column connected to receive an expanded liquid stream, the distillation column being adapted to separate said stream into a more volatile stream of distillation steam and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (5) a third heat transfer means coupled to the combine means in order to receive the combined stream and cool it enough to partially condense it; (5) a second expansion means connected to the third heat exchange means in order to receive a substantially condensed first gaseous stream and expand it to an intermediate pressure; (5) a third expansion means connected to the first separation means in order to receive the second gaseous stream and expand it to the specified intermediate pressure; (5) a second expansion means connected to the third heat exchange means in order to receive a substantially condensed first gaseous stream and expand it to an intermediate pressure; (5) a third expansion means connected to the separation means in order to receive the second gaseous stream and expand it to the specified intermediate pressure; (5) a distillation column connected to receive an expanded vapor stream and an expanded first liquid stream, the distillation column being adapted to separate said streams into a volatile fraction of the residual gas containing the bulk of methane and lighter components, and relatively less a volatile fraction containing the bulk of the heavier hydrocarbon components; (5) a separation means connected to the first heat exchange means in order to receive the condensed part and divide it into at least two parts, thereby forming a condensed stream and a liquid stream, wherein the separation means is further connected with a distillation column in order to direct the specified flow of liquid into the distillation column with a feed into it from above; and (6) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature at the top of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered from the relatively less volatile fraction. (5) at least an expanded steam stream and an expanded liquid stream are sent to a distillation column in which said streams are separated into a volatile fraction of the residual gas containing the bulk of methane and lighter components, and a relatively less volatile fraction containing the bulk of heavier hydrocarbon components; and (6) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (5) the distillation vapor stream is diverted from the distillation column section below the expanded first vapor stream and cooled sufficiently to condense at least a portion thereof, thereby forming a second vapor stream and a second liquid stream; (5) at least a portion of the expanded cooled natural gas stream is brought into intimate contact with at least a fraction of the remaining portion of the liquid stream in the distillation column; (5) the distillation liquid stream is diverted from the distillation column at a location that is higher than the portion from which the distillation steam stream is diverted, after which the distillation liquid stream is heated and then again directed to the distillation column, as another supply thereto, at a location lower than the portion from where the distillation steam stream is diverted; (5) the distillation vapor stream is diverted from the distillation column section below the expanded first vapor stream and cooled sufficiently to condense at least a portion thereof, thereby forming a second vapor stream and a second liquid stream; (5) at least a portion of the expanded cooled natural gas stream is brought into intimate contact with at least a fraction of the remaining portion of the liquid stream in the distillation column; (5) the distillation vapor stream is diverted from the distillation column section below the expanded first vapor stream and cooled sufficiently to condense at least a portion thereof, thereby forming a second vapor stream and a second liquid stream; (5) the steam stream is combined with a more volatile distillation steam stream in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components; and (6) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (5) the first fluid stream is expanded to a specified intermediate pressure; (5) a portion of the second liquid stream is sent to a distillation column with a feed to it from above; (5) the first fluid stream is expanded to a specified intermediate pressure; (5) at least a portion of the expanded cooled natural gas stream is brought into intimate contact with at least a portion of the second liquid stream in the contacting device; and (6) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (5) a second liquid stream and an expanded first liquid stream are sent to a distillation column in which said streams are separated into a more volatile stream of distillation steam and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (5) a portion of the second liquid stream is sent to said distillation column with a feed thereto from above; (5) a second liquid stream and an expanded first liquid stream are sent to a distillation column in which said streams are separated into a more volatile stream of distillation steam and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (5) at least a portion of the expanded cooled natural gas stream is brought into intimate contact with at least a portion of the second liquid stream in the contacting device; and (6) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (5) the second fluid stream is expanded to a lower intermediate pressure; (5) an expanded liquid stream is sent to a distillation column in which said stream is separated into a more volatile stream of distillation steam and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (5) the combined stream is cooled in order to condense it substantially completely and then expand to an intermediate pressure; (5) the second gaseous stream is expanded to an intermediate pressure; (5) the expanded, substantially condensed first gaseous stream and the expanded second gaseous stream are sent to a distillation column in which said streams are separated into a volatile fraction of the residual gas containing the bulk of methane and lighter components, and a relatively less volatile fraction containing the main part of the heavier hydrocarbon components; (5) the combined stream is cooled in order to condense it substantially completely, and then expand it to an intermediate pressure; 5. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form said liquefied natural gas stream; wherein (1) the natural gas stream is processed in one or more cooling stages in order to partially condense it; (5) the second gaseous stream is expanded to the specified intermediate pressure; (5) the expanded, substantially condensed first gaseous stream and the expanded second gaseous stream are sent to a distillation column in which said streams are separated into a volatile fraction of the residual gas containing the bulk of methane and lighter components, -16005326 and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; and (6) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (5) at least an expanded steam stream and an expanded first liquid stream are sent to a distillation column in which said streams are separated into a volatile fraction of the residual gas containing the bulk of methane and lighter components, and a relatively less volatile fraction containing the bulk of more heavy hydrocarbon components; (5) the condensed part is divided into at least two parts in order to thereby form said condensed stream and a liquid stream; and (6) the liquid stream is sent to the distillation column with a feed into it from above. (6) a first heat exchange means connected to the distillation column in order to receive the volatile fraction of the residual gas, the first heat exchange means adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof and thus forming a condensed stream; and (7) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature in the upper part of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (6) steam venting means connected to the distillation column in order to receive a distillation steam stream from the distillation column section below the expanded first vapor stream; (6) a separation means connected to a third heat exchange means in order to receive a cooled distillation steam stream and separate it into a steam stream and a liquid stream; (6) steam venting means connected to the distillation column in order to receive a distillation steam stream from a portion of this distillation column below the expanded first vapor stream; (6) a separation means coupled to a third heat exchange means in order to receive a cooled distillation steam stream and separate it into a steam stream and a liquid stream; (6) steam venting means connected to the distillation column in order to receive a distillation steam stream from the distillation column section below the expanded first vapor stream; (6) a separation means coupled to a third heat exchange means in order to receive a cooled distillation steam stream and separate it into a steam stream and a liquid stream; (6) steam venting means connected to the distillation column in order to receive a distillation steam stream from the distillation column section below the expanded first vapor stream; -40005326 (7) a third heat transfer means connected to the steam removal means in order to receive the distillation steam stream and cool it enough to condense at least a portion thereof; (6) a separation means coupled to a third heat exchange means in order to receive a cooled distillation steam stream and separate it into a steam stream and a liquid stream; (6) a third expansion means connected to the separation means in order to receive the first fluid stream and expand it to the specified intermediate pressure; (6) a fourth heat exchange means connected to the distillation column in order to receive a more volatile stream of distillation steam and cool it enough to condense at least a portion thereof; (6) a third expansion means connected to the separation means in order to receive the first fluid stream and expand it to the specified intermediate pressure; (6) a fourth heat exchange means connected to the distillation column in order to receive a more volatile stream of distillation steam and cool it enough to condense at least a portion of it, thereby forming a second liquid stream; (6) a distillation column connected to receive a second liquid stream and an expanded first liquid stream, wherein the distillation column is adapted to separate said streams into a more volatile distillation vapor stream and a relatively less volatile fraction containing a majority of the heavier components hydrocarbons; (6) a separation means connected to a third heat exchange means in order to receive a cooled more volatile distillation steam stream and to separate it into a second steam stream and a second liquid stream; (6) a distillation column connected to receive a second liquid stream and an expanded first liquid stream, wherein the distillation column is adapted to separate said streams into a more volatile distillation vapor stream and a relatively less volatile fraction containing a majority of the heavier components hydrocarbons; (6) wherein the contacting and separation means is further connected to the third heat exchange means in order to receive the second liquid stream, so that at least a portion of the expanded cooled natural gas stream is in intimate contact with at least a fraction of the second liquid stream in the device for contacting; (6) a fourth expansion means connected to the first separation means in order to receive the first fluid stream and expand it to the specified lower intermediate pressure; (6) a combining means connected to a separation means and a distillation column in order to receive a vapor stream and a more volatile vapor distillation stream and combine them to form a volatile residual gas fraction containing a majority of methane and lighter components ; -32005326 (7) a first heat transfer means connected to a combining means for receiving a volatile fraction of the residual gas, the first heat exchange means adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least part of it and thus form a condensed stream; and (8) control means adapted to control the amount and temperature of the feed stream to the distillation column in order to maintain the temperature at the top of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (6) second expansion means connected to the third heat exchange means in order to receive the substantially condensed combined stream and expand it to an intermediate pressure; (6) a third expansion means connected to the first separation means in order to receive the second gaseous stream and expand it to the specified intermediate pressure; (6) a distillation column connected to receive an expanded, substantially condensed first gaseous stream and an expanded second gaseous stream, the distillation column being adapted to separate said streams into a volatile fraction of the residual gas containing the bulk of methane or more light components, and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (6) second expansion means connected to the third heat exchange means in order to receive the substantially condensed combined stream and expand it to an intermediate pressure; (6) a third expansion means connected to the separation means in order to receive the second gaseous stream and expand it to the specified intermediate pressure; (6) a distillation column connected to receive an expanded, substantially condensed first gaseous stream and an expanded second gaseous stream, the distillation column being adapted to separate said streams into a volatile fraction of the residual gas containing the bulk of methane or more light components, and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (6) a first heat exchange means connected to the distillation column in order to receive a volatile fraction of the residual gas, the first heat exchange means adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof; (6) a portion of the second liquid stream is fed to the distillation column as another feed into it at the feed point, essentially in the same area from which the distillation steam stream is taken off; (6) the distillation liquid stream is diverted from the distillation column at a location which is higher than the portion from which the distillation steam stream is taken off, the distillation liquid stream is heated and then re-directed to the distillation column as another supply thereto to a place below the portion from which the steam stream is removed distillation; (6) at least a portion of the expanded first vapor stream is brought into intimate contact with at least a portion of the second liquid stream in the distillation column; (6) the steam stream is combined with a more volatile distillation steam stream in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components; and (7) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (6) a portion of the second liquid stream is supplied to the distillation column, as another supply thereto, to the supply point, essentially in the same section from which the distillation steam stream is removed; (6) the steam stream is combined with a more volatile distillation steam stream in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components; and (7) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (6) at least a portion of the expanded first vapor stream is brought into intimate contact with at least a portion of the second liquid stream in the distillation column; (6) the heated second liquid stream and the expanded first liquid stream are sent to a distillation column in which said streams are separated into a more volatile stream of distillation steam and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (6) at least a portion of the expanded cooled natural gas stream is brought into intimate contact with at least a fraction of the remaining portion of the second liquid stream in the contacting device; (6) the heated second liquid stream and the expanded first liquid stream are sent to a distillation column in which said streams are separated into a more volatile stream of distillation steam and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (6) a more volatile vapor distillation stream is cooled sufficiently to condense at least a portion thereof, thereby forming a third vapor stream and a third liquid stream; (6) at least a portion of the expanded cooled natural gas stream is brought into intimate contact with at least a fraction of the remaining portion of the second liquid stream in the contacting device; (6) a more volatile vapor distillation stream is cooled sufficiently to condense at least a portion thereof, thereby forming a third liquid stream; (6) the first fluid stream is expanded to a lower intermediate pressure; (6) a more volatile steam distillation stream is combined with a steam stream in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components; and (7) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (6) the second gaseous stream is expanded to an intermediate pressure; (6) the first fluid stream is expanded to a specified intermediate pressure; (6) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion thereof; 6. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, in which (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages; (6) the second gaseous stream is expanded to the specified intermediate pressure; (6) the fluid flow is expanded to the specified intermediate pressure; (6) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion thereof; (7) a third heat transfer means coupled to the steam removal means in order to receive a steam stream of distillation and cool it sufficiently to condense at least a portion thereof; (7) a separation means connected to the separation means in order to receive a liquid stream, and in order to separate it into at least a first part and a second part, the separation means being further connected to the distillation column so that supply the first part of the liquid stream to the distillation column at the supply point, essentially in the same area in which the distillation steam stream is discharged; -44005326 (8) wherein the distillation column is further connected to a separation means in order to receive the second part of the liquid stream so that at least a part of the expanded cooled natural gas stream comes into intimate contact with at least a part of the second part of the liquid stream in the distillation the column; (7) a third heat transfer means coupled to the steam removal means in order to receive a steam stream of distillation and cool it sufficiently to condense at least a portion thereof; (7) wherein the distillation column is further connected to a separation means in order to receive a liquid stream such that at least a portion of the expanded cooled natural gas stream is in intimate contact with at least a portion of the liquid stream in the distillation column; (7) a third heat transfer means coupled to the steam removal means in order to receive a steam stream of distillation and cool it sufficiently to condense at least a portion thereof; (7) separation means connected to separation means in order to receive a liquid stream and in order to separate it into at least a first part and a second part, said separation means being further connected to a distillation column in order to supply the first part of the liquid stream to the distillation column at the feed point, essentially in the same area in which the distillation steam stream is discharged; (7) wherein the distillation column is further connected to a separation means in order to receive a liquid stream such that at least a portion of the cooled expanded natural gas stream is in intimate contact with at least a portion of the liquid stream in the distillation column; (7) a distillation column connected to receive a heated second liquid stream and an expanded first liquid stream, the distillation column being adapted to separate the streams into a more volatile distillation vapor stream and a relatively less volatile fraction containing a majority of the heavier components hydrocarbons; (7) a separation means connected to a fourth heat exchange means in order to receive a cooled more volatile distillation steam stream and to separate it into a second steam stream and a second liquid stream; (7) a distillation column connected to receive a heated second liquid stream and an expanded first liquid stream, the distillation column being adapted to separate the streams into a more volatile distillation vapor stream and a relatively less volatile fraction containing a majority of the heavier components hydrocarbons; (7) wherein the contacting and separating means is further connected to the fourth heat exchange means in order to receive the second liquid stream so that at least a portion of the expanded cooled natural gas stream is in intimate contact with at least a fraction of the second liquid stream in the device for contacting; (7) a third heat transfer means connected to the distillation column in order to receive a more volatile stream of distillation steam and cool it enough to condense at least a portion thereof; (7) a separation means connected to the separation means in order to receive a second liquid stream and to separate it into at least a first part and a second part, the separation means being further connected to the distillation column so that to feed the first part of the second fluid stream into the distillation column with a feed into it from above; (7) a third heat exchange means connected to the distillation column in order to receive a more volatile stream of distillation steam and cool it enough to condense at least a portion thereof, thereby forming a third liquid stream; (7) a first heat exchange means connected to the contacting and separation means in order to receive the volatile fraction of the residual gas, wherein the first heat exchange means is adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least part of it and thus form a condensed stream; and (8) control means adapted to control the amounts and temperatures of the feed streams to the contacting and separation means and the distillation column in order to maintain the temperatures in the upper part of the contacting and separation means and the distillation column at temperatures by which the main some of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (7) a distillation column connected to receive an expanded second liquid stream and an expanded first liquid stream, wherein the distillation column is adapted to separate said streams into a more volatile distillation vapor stream and a relatively less volatile fraction containing a majority of the heavier hydrocarbon components; (7) a third expansion means connected to the first separation means in order to receive the second gaseous stream and expand it to the specified intermediate pressure; (7) a fourth expansion means connected to the separation means in order to receive the first gaseous stream and expand it to the specified intermediate pressure; (7) a first heat exchange means connected to the distillation column in order to receive a volatile fraction of the residual gas, the first heat exchange means adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof; (7) a third expansion means connected to the separation means in order to receive the second gaseous stream and expand it to an intermediate pressure; (7) a fourth expansion means connected to the separation means in order to receive a fluid stream and expand it to a specified intermediate pressure; (7) a first heat exchange means connected to the distillation column in order to receive the volatile fraction of the residual gas, wherein the first heat exchange means is adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof and thus forming a condensed stream; and (8) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature at the top of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. -28005326 (7) a separation means connected to the first heat exchange means in order to receive the condensed part and divide it into at least two parts, thereby forming a condensed stream and a second liquid stream, wherein the separation means is furthermore connected to the distillation column in order to direct a second liquid stream into the distillation column with a feed to it from above; and (8) control means adapted to control the amounts and temperatures of said feed streams to the distillation column in order to maintain the temperature in the upper part of the distillation column at a temperature by which the bulk of the components of the heavier hydrocarbons are recovered in a relatively less volatile fraction . (7) at least a portion of the expanded first vapor stream is brought into intimate contact with at least a fraction of the remaining portion of the second liquid stream in the distillation column; -25005326 (8) the distillation liquid stream is diverted from the distillation column at a location that is higher than the portion from which the distillation steam stream is diverted, after which the distillation liquid stream is heated and then again directed to the distillation column, as another supply to it at a location lower the area from which the distillation steam stream is diverted; (7) the steam stream is combined with a more volatile distillation steam stream in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components; and (8) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (7) the distillation liquid stream is diverted from the distillation column at a location that is higher than the portion from which the distillation steam stream is diverted, after which the distillation liquid stream is heated and then sent back to the distillation column as another feed to it at a location lower than the portion from where distillation steam is diverted; (7) at least a portion of the expanded first vapor stream is brought into intimate contact with at least a fraction of the remaining portion of the second liquid stream in the distillation column; (7) a second vapor stream is combined with a more volatile distillation vapor stream in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components; and (8) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (7) a more volatile vapor distillation stream is cooled sufficiently to condense at least a portion thereof, thereby forming a third vapor stream and a third liquid stream; (7) the first steam stream is combined with the second steam stream in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components; and (8) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (7) a more volatile vapor distillation stream is cooled sufficiently to condense at least a portion thereof, thereby forming a third liquid stream; (7) a portion of the third fluid stream is sent to a distillation column with a feed to it from above; (7) the first steam stream is combined with the second steam stream in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components; and (8) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (7) at least a portion of the expanded vapor stream is brought into intimate contact with at least a portion of the third liquid stream in the contacting device; and (8) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (7) the expanded second liquid stream and the expanded first liquid stream are sent to a distillation column in which said streams are separated into a more volatile stream of distillation steam and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (7) any remaining portion of the first fluid stream is expanded to a specified intermediate pressure; (7) the expanded, substantially condensed first gaseous stream, the expanded second gaseous stream, and the expanded first liquid stream are sent to a distillation column in which said streams are separated into a volatile fraction of the residual gas containing the bulk of methane and lighter components, and relatively less a volatile fraction containing the bulk of the heavier hydrocarbon components; 7. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; wherein (1) the natural gas stream is treated in one or more cooling steps in order to partially condense it; (7) the condensed portion is divided into at least two parts to thereby form a condensed stream and a liquid stream; and (8) the liquid stream is sent to the distillation column with a feed into it from above. (7) any remaining portion of the fluid stream is expanded to a specified intermediate pressure; (7) the expanded, substantially condensed first gaseous stream, the expanded second gaseous stream, and the expanded liquid stream are sent to a distillation column in which said streams are separated into a volatile fraction of the residual gas containing the bulk of methane and lighter components, and relatively less volatile a fraction containing the bulk of the heavier hydrocarbon components; and (8) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (7) the condensed portion is divided into at least two parts to thereby form a condensed stream and a second liquid stream; and (8) a second fluid stream is sent to a distillation column with a feed thereto from above. (8) a second separation means coupled to a third heat exchange means in order to receive a cooled distillation steam stream and separate it into a second vapor stream and a second liquid stream; (8) a second separation means connected to a third heat exchange means in order to receive a cooled distillation steam stream and separate it into a second steam stream and a second liquid stream; (8) liquid withdrawal means connected to the distillation column in order to receive a distillation liquid stream from a portion of the distillation column above the vapor withdrawal means; (8) a second separation means connected to a third heat exchange means in order to receive a cooled distillation steam stream and separate it into a second steam stream and a second liquid stream; (8) wherein the distillation column is further connected to a separation means in order to receive the second part of the liquid stream so that at least a portion of the expanded cooled natural gas stream is in intimate contact with at least a fraction of the second part of the liquid stream in the distillation the column; (8) a second separation means connected to a third heat exchange means in order to receive a cooled distillation steam stream and separate it into a second steam stream and a second liquid stream; (8) a combining means connected to a distillation column and a separating means in order to receive a more volatile distillation steam stream and a steam stream and combine them to form a volatile residual gas fraction containing the bulk of methane and lighter components ; (8) a fourth heat exchange means connected to the distillation column in order to receive a more volatile stream of distillation steam and cool it enough to condense at least a portion thereof; (8) a separation means connected to a separation means in order to receive a second liquid stream and in order to separate it into at least a first part and a second part, the separation means being further connected to a distillation column for supplying the first part a second fluid stream into the distillation column with a feed into it from above; (8) a fourth heat exchange means connected to the distillation column in order to receive a more volatile stream of distillation steam and cool it enough to condense at least a portion thereof, thereby forming a third liquid stream; -37005326 (9) wherein the means for contacting and separating is additionally connected to said fourth means for heat exchange in order to receive a third liquid stream so that at least a portion of the expanded first vapor stream comes into close contact with at least a fraction of the third fluid flow in the contacting device; (8) a first heat exchange means connected to the contacting and separation means in order to receive the volatile fraction of the residual gas, wherein the first heat exchange means is adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least part of it and thus form a condensed stream; and (9) control means adapted to control the quantities and temperatures of the feed streams to the contacting and separation means and the distillation column in order to maintain the temperatures in the upper part of the contacting and separation means and the distillation column at temperatures by which the main some of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (8) a second separation means connected to a third heat exchange means in order to receive a cooled more volatile distillation steam stream and to separate it into a third steam stream and a third liquid stream; (8) wherein the contacting and separating means is further connected to the separating means in order to receive the second part of the second liquid stream so that at least a portion of the expanded cooled natural gas stream is in intimate contact with at least a fraction of the second part said second fluid stream in a contacting device; (8) wherein the contacting and separation means is further connected to the third heat exchange means in order to receive the third liquid stream so that at least a portion of the expanded vapor stream comes into intimate contact with at least a fraction of the third liquid stream in the device for contacting; (8) combining means connected to a second separation means and to a distillation column in order to receive a second vapor stream or more than a volatile distillation vapor stream and combine them to form a volatile residual gas fraction containing a majority of methane or more light components; (8) a fourth expansion means coupled to the separation means in order to receive any remaining portion of the first fluid stream and expand it to a specified intermediate pressure; (8) a distillation column connected to receive an expanded, substantially condensed gaseous stream, an expanded second gaseous stream, and an expanded first liquid stream, the distillation column being adapted to separate said streams into a volatile fraction of the residual gas containing the main a portion of methane and lighter components, and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (8) a second separation means connected to the first heat exchange means in order to receive the condensed part and divide it into at least two parts, thereby forming a condensed stream and a liquid stream, the second separation means being further connected to distillation column in order to direct the flow of liquid into the distillation column with the flow into it from above; and (9) control means adapted to control the quantities and temperatures of the feed streams to the distillation column in order to maintain the temperature in the upper -30005326 parts of a distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (8) a fourth expansion means connected to the separation means in order to receive any remaining part of the liquid stream and expand it to the specified intermediate pressure; (8) a distillation column connected to receive an expanded, substantially condensed first gaseous stream, an expanded second gaseous stream, and an expanded liquid stream, the distillation column being adapted to separate the streams into a volatile fraction of the residual gas containing the main part methane and lighter components, and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (8) a second vapor stream is combined with a more volatile distillation vapor stream in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components; and (9) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (8) a second vapor stream is combined with a more volatile distillation vapor stream in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components; and (9) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (8) a portion of the third fluid stream is sent to a distillation column with a feed to it from above; (8) at least a portion of the expanded vapor stream is brought into intimate contact with at least a portion of the third liquid stream in the contacting device; and -21005326 (9) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (8) at least a portion of the expanded first vapor stream is brought into intimate contact with at least a fraction of the remaining portion of the third liquid stream in the contacting device; (8) a stream of more volatile distillation steam is combined with a second steam stream in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components; and (9) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (8) the expanded, substantially condensed combined stream, the expanded second gaseous stream, and the remainder of the first liquid stream are sent to a distillation column in which said streams are separated into a volatile fraction of the residual gas containing the main -18005326 part of methane and lighter components, and a relatively less volatile fraction containing the bulk of the heavier components of hydrocarbons; 8. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion thereof and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; wherein (1) the natural gas stream is treated in one or more cooling steps in order to partially condense it; (8) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion thereof; (8) the expanded, substantially condensed combined stream, the expanded second gaseous stream, and the remainder of the liquid stream are sent to a distillation column in which said streams are separated into a volatile fraction of the residual gas containing a majority of methane and lighter components and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; and (9) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (9) a separation means connected to the second separation means in order to receive a second liquid stream and to separate it into at least a first part and a second part, the separation means being further connected to a distillation column in order to supply the first part a second liquid stream to the distillation column at the feed point, essentially in the same area in which the distillation steam stream is discharged; (9) liquid withdrawal means connected to the distillation column in order to receive a stream of distillation liquid from a portion of the distillation column above the vapor withdrawal means; (9) wherein the distillation column is further connected to a separation means in order to receive a second liquid stream such that at least a portion of the expanded first vapor stream is in intimate contact with at least a portion of the second liquid stream in the distillation column; (9) a fourth heat exchange means connected to the liquid removal means in order to receive the distillation liquid stream and heat it, the fourth heat exchange means further connected to the distillation column in order to supply the heated distillation liquid stream to the distillation column in place below means for the removal of steam; (9) a separation means connected to the second separation means in order to receive a second liquid stream and in order to separate it into at least a first part and a second part, wherein the separation means is further connected to the distillation column in order to in order to feed the first part of the second liquid stream to the distillation column at the supply point, essentially in the same area where the distillation steam stream is discharged; (9) a combining means connected to a distillation column and a separating means in order to receive a more volatile distillation steam stream and a steam stream and combine them to form a volatile residual gas fraction containing a majority of methane and lighter components ; (9) wherein the distillation column is further connected to the second separation means in order to receive a second liquid stream so that at least a portion of the expanded first vapor stream is in intimate contact with at least a portion of the second liquid stream in the distillation column; (9) a first heat transfer means coupled to a combining means for receiving a volatile fraction of the residual gas, the first heat exchange means being adapted to cool the volatile fraction of the residual gas under pressure to condense at least a portion thereof and form thus a condensed stream; and (10) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature at the top of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (9) a second separation means connected to a fourth heat exchange means in order to receive a cooled more volatile distillation steam stream and to separate it into a third steam stream and a third liquid stream; (9) wherein the contacting and separating means is further connected to the separating means in order to receive the second part of the second liquid stream so that at least a portion of the expanded cooled natural gas stream is in intimate contact with at least a fraction of the second part a second fluid stream in the contacting device; (9) a separation means connected to the second separation means in order to receive a third liquid stream and to separate it into at least a first part and a second part, the separation means being further connected to a distillation column in order to to supply the first part of the third fluid stream to the distillation column with a feed into it from above; (9) a combining means connected to a contacting and separating means and a separating means in order to receive a first steam stream and a second steam stream and combine them to form a volatile residual gas fraction containing a majority of methane and more light components; (9) a first heat exchange means coupled to a contacting and separation means in order to receive a volatile fraction of the residual gas, the first heat exchange means -34005326 is adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion of it and thereby form a condensed stream; and (10) control means adapted to control the amounts and temperatures of the feed streams to the contacting and separation means and the distillation column in order to maintain the temperatures in the upper part of the contacting and separation means and the distillation column at temperatures by which the main some of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (9) a first heat exchange means connected to a combining means for receiving a volatile fraction of the residual gas, wherein the first heat exchange means is adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof and thus form a condensed stream; and (10) control means adapted to control the amount and temperature of the feed streams to the distillation column in order to maintain the temperature at the top of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (9) a distillation column connected to receive an expanded, substantially condensed combined stream, an expanded second gaseous stream, and an expanded remaining portion of the first liquid stream, the distillation column being adapted to separate the streams into a volatile residual gas fraction containing the bulk of methane and lighter components, and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (9) a first heat exchange means connected to the distillation column in order to receive a volatile fraction of the residual gas, the first heat exchange means adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof; (9) a distillation column connected to receive an expanded, substantially condensed combined stream, an expanded second gaseous stream, and an expanded remaining portion of the liquid stream, the distillation column being adapted to separate said streams into a volatile residual gas fraction containing the bulk of methane and lighter components, and a relatively less volatile fraction containing the bulk of the heavier hydrocarbon components; (9) a first heat exchange means connected to the distillation column in order to receive a volatile fraction of the residual gas, the first heat exchange means adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof and to form in this way a condensed stream; and (10) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature at the top of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (9) a second vapor stream is combined with a more volatile distillation vapor stream in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components; and (10) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. (9) at least a portion of the expanded first vapor stream is brought into intimate contact with at least a fraction of the remaining portion of the third liquid stream in the contacting device; (9) a second steam stream is combined with a third steam stream in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components; and (10) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion thereof and thereby form a condensed stream. 9. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages; (9) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion thereof; (9) the condensed portion is divided into at least two parts to thereby form a condensed stream and a second liquid stream; and (10) a second fluid stream is directed to the said distillation column with a feed into it from above. (10) wherein the distillation column is further connected to separation means in order to receive the second part of the second liquid stream so that at least a portion of the expanded first vapor stream comes into intimate contact with at least a fraction of the second part of the second liquid stream in distillation column; -45005326 (11) liquid withdrawal means connected to the distillation column in order to receive a distillation liquid stream from a portion of the distillation column above the vapor withdrawal means; (10) a fourth heat exchange means connected to the liquid removal means in order to receive the distillation liquid stream and heat it, the fourth heat exchange means further connected to the distillation column in order to supply the heated distillation liquid stream to the distillation column in place below means for the removal of steam; (10) liquid withdrawal means connected to the distillation column in order to receive a distillation liquid stream from a portion of the distillation column above the vapor withdrawal means; (10) a combining means connected to a distillation column and a separating means in order to receive a more volatile distillation steam stream and a steam stream, and combine them to form a volatile residual gas fraction containing a majority of methane and lighter components ; (10) wherein the distillation column is connected to a separation means in order to receive the second part of the second liquid stream so that at least a portion of the expanded first vapor stream comes into close contact with at least a fraction of the second part of the second liquid stream in the distillation the column; (10) a first heat transfer means connected to a combining means in order to receive a volatile fraction of the residual gas, wherein the first heat transfer means is adapted -41005326 in order to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion of it and thereby form a condensed stream; and (11) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature in the upper part of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (10) a combining means connected to a distillation column and a separating means in order to receive a more volatile distillation steam stream and a second steam stream and combine them to form a volatile residual gas fraction containing a majority of methane and lighter components ; (10) a separation means connected to the second separation means in order to receive the third liquid stream and in order to separate it at least into the first part and the second part, the separation means being further connected to the distillation column in order to to supply the first part of the third fluid stream to the distillation column as a feed into it from above; (10) a combining means connected to a contacting and separating means and a separating means for receiving a first vapor stream and a second vapor stream and combining them to form a volatile residual gas fraction containing a majority of methane and lighter components; (10) a first heat exchange means connected to the contacting and separation means in order to receive the volatile fraction of the residual gas, wherein the first heat exchange means is adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least part of it and thus form a condensed stream; and (11) control means adapted to control the amounts and temperatures of the feed streams to the contacting and separation means and the distillation column in order to maintain the temperatures in the upper part of the contacting and separation means and the distillation column at temperatures by which the main some of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (10) wherein the contacting and separating means is further connected to the separating means in order to receive the second part of the third liquid stream, so that at least a part of the expanded first vapor stream comes into close contact with at least a fraction of the second part of the third fluid flow in the contacting device; (10) the first heat transfer means is connected to the combining means in order to receive the volatile fraction of the residual gas, wherein the first heat exchange means is adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof and form such image condensed stream; and (11) control means adapted to control the amounts and temperatures of the feed streams to the contacting and separation means and the distillation column in order to maintain the temperatures in the upper part of the contacting and separation means and the distillation column at temperatures by which the main some of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (10) a first heat exchange means connected to the distillation column to receive a volatile fraction of the residual gas, the first heat exchange means adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof; (10) a second separation means connected to the first heat exchange means in order to receive the condensed part and divide it into at least two parts, thereby forming a condensed stream and a second liquid stream, the second separation means being furthermore connected to the distillation column in order to direct a second liquid stream into the distillation column with a feed to it from above; and (11) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature in the upper part of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (10) a first heat exchange means connected to the distillation column in order to receive a volatile fraction of the residual gas, the first heat exchange means adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof and thus forming a condensed stream; and (11) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature in the upper part of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (10) a second steam stream is combined with a third steam stream in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components; and (11) the volatile fraction of the residual gas is cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. 10. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion thereof and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages in order to partially condense it; (10) the condensed portion is divided into at least two parts to thereby form a condensed stream and a second liquid stream; and (11) said second fluid stream is directed to said distillation column with a feed to it from above. (11) a combining means connected to a distillation column and a separating means in order to receive a more volatile distillation steam stream and a steam stream and combine them to form a volatile residual gas fraction containing a majority of methane and lighter components; (11) a fourth heat exchange means connected to the liquid removal means in order to receive the distillation liquid stream and heat it, the fourth heat exchange means further connected to the distillation column in order to supply the heated distillation liquid stream to the distillation column in place below means for the removal of steam; (11) a first heat exchange means connected to a combining means for receiving a volatile fraction of the residual gas, wherein the first heat exchange means is adapted to cool the volatile fraction of the residual gas under pressure to condense at least a portion thereof and form thus condensed stream; and (12) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature in the upper part of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (11) a combining means connected to a distillation column and a separating means in order to receive a more volatile steam distillation stream and a second steam stream and combine them to form a volatile residual gas fraction containing a majority of methane and lighter components ; (11) a first heat exchange means connected to a combining means for receiving a volatile fraction of the residual gas, wherein the first heat exchange means is adapted to cool the volatile fraction of the residual gas under pressure to condense at least a portion thereof and form thus condensed stream; and (12) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature in the upper part of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (11) wherein the contacting and separating means is further connected to the separating means in order to receive the second part of the third liquid stream so that at least a portion of the expanded first natural gas stream is in intimate contact with at least a fraction of the second part a third fluid stream in the contacting device; (11) a first heat exchange means connected to a combining means for receiving a volatile fraction of the residual gas, wherein the first heat exchange means is adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof and thus form a condensed stream; and (12) control means adapted to control the amounts and temperatures of the feed streams to the contacting and separation means and the distillation column in order to maintain the temperatures at the top of the contacting and separation means and distillation -38005326 columns at temperatures by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (11) a combining means coupled to a contacting and separating means and a separating means in order to receive a second vapor stream and a third vapor stream and combine them to form a volatile residual gas fraction containing a majority of methane and lighter components; (11) a second separation means connected to the first heat exchange means in order to receive the condensed part and divide it into at least two parts, thereby forming a condensed stream and a second liquid stream, the second separation means being further connected with a distillation column in order to direct a second liquid stream into the distillation column with a feed into it from above; and (12) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature in the upper part of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. 11. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion thereof and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages; (12) a fourth heat exchange means connected to the liquid removal means in order to receive the distillation liquid stream and heat it, the fourth heat exchange means further connected to the distillation column in order to supply the heated distillation liquid stream to the distillation column in place below means for removing steam; (12) a first heat transfer means coupled to a combining means for receiving a volatile fraction of the residual gas, the first heat exchange means being adapted to cool the volatile fraction of the residual gas under pressure to condense at least a portion thereof and form thus condensed stream; and (13) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature at the top of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (12) a combining means connected to a distillation column and a separating means in order to receive a more volatile distillation vapor stream and a second vapor stream and combine them to form a volatile residual gas fraction containing a majority of methane and lighter components ; (12) a first heat transfer means coupled to a combining means for receiving a volatile fraction of the residual gas, the first heat exchange means being adapted to cool the volatile fraction of the residual gas under pressure to condense at least a portion thereof and form thus indicated condensed stream; and (13) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature at the top of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (12) a combining means connected to a contacting and separating means and a second separating means in order to receive a second vapor stream and a third vapor stream and combine them to form a volatile fraction of the residual gas containing the bulk methane and more light components; (12) a first heat exchange means coupled to a combining means for receiving a volatile fraction of the residual gas, the first heat exchange means adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof and thus form a condensed stream; and (13) control means adapted to control the amounts and temperatures of the feed streams to the contacting and separation means and the distillation column in order to maintain the temperatures in the upper part of the contacting and separation means and the distillation column at temperatures by which the main some of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. 12. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages in order to partially condense it; (13) a combining means connected to a distillation column and a second separation means in order to receive a more volatile distillation steam stream and a second vapor stream and combine them to form a residual gas volatile fraction containing a majority of methane and more light components; (13) a first heat exchange means connected to a combining means for receiving said volatile fraction of the residual gas, wherein the first heat exchange means is adapted to cool the volatile fraction of the residual gas under pressure to condense at least a portion thereof and thus forming a condensed stream; and (14) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature at the top of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. (13) a first heat exchange means connected to a combining means for receiving a volatile fraction of the residual gas, wherein the first heat exchange means is adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof and thus form a condensed stream; and (14) control means adapted to control the amounts and temperatures of the feed streams to the contacting and separation means and the distillation column in order to maintain the temperatures in the upper part of the contacting and separation means and the distillation column at temperatures by which the main some of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. 13. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages; (14) a first heat transfer means connected to a combining means for receiving a volatile fraction of the residual gas, the first heat exchange means adapted to cool the volatile fraction of the residual gas under pressure in order to condense at least a portion thereof and thus form a condensed stream; and (15) control means adapted to control the amounts and temperatures of the feed streams to the distillation column in order to maintain the temperature at the top of the distillation column at a temperature by which the bulk of the heavier hydrocarbon components are recovered in a relatively less volatile fraction. 14. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover -20005326 (1) a natural gas stream is processed in one or more cooling steps to partially condense it; 15. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is processed in one or more cooling stages; 16. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion thereof and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages in order to partially condense it; 17. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages; 18. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages in order to partially condense it; 19. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages; 20. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages in order to partially condense it; 21. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages; 22. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, in which (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and -23005326 (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages in order to partially condense it; 23. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages; 24. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages in order to partially condense it; 25. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages; 26. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, (1) the natural gas stream is treated in one or more cooling stages in order to partially condense it; 27. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, the method consists essentially of processing stages, where (1) the natural gas stream is treated in one or more cooling stages; 28. A method of liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein (a) the natural gas stream is cooled under pressure in order to condense at least a portion of it and form a condensed stream; and (b) the condensed stream is expanded to a lower pressure in order to form a stream of liquefied natural gas; moreover, the method consists essentially of processing stages, where (1) the natural gas stream is treated in one or more cooling stages in order to partially condense it; 29. The method according to claims 3, 4, 5, 11-27 or 28, in which the volatile fraction of the residual gas is compressed and then cooled under pressure in order to condense at least a portion of it and thereby form a condensed stream. 30. The method according to claim 1 or 6, in which (1) the volatile fraction of the residual gas is compressed and then cooled under pressure in order to condense at least part of it; and (2) the condensed portion is divided into at least two parts in order to thereby form a condensed stream and a liquid stream. 31. The method according to claims 2, 7 or 8, in which (1) the volatile fraction of the residual gas is compressed and then cooled under pressure in order to condense at least part of it; and (2) the condensed portion is divided into at least two parts in order to thereby form a condensed stream and a second liquid stream. 32. The method according to claim 9, in which a more volatile stream of steam distillation is compressed and then combined with a stream of steam in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components. 33. The method according to claim 10, in which a more volatile stream of steam distillation is compressed and then combined with a second stream of steam in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components. -26005326 34. The method according to PP.3-5, 11-27 or 28, in which the volatile fraction of the residual gas is heated, compressed and then cooled under pressure in order to condense at least part of it and thus form a condensed stream. 35. The method according to claim 1 or 6, in which (1) the volatile fraction of the residual gas is heated, compressed and then cooled under pressure in order to condense at least part of it; and (2) the condensed portion is divided into at least two parts in order to thereby form a condensed stream and a liquid stream. 36. The method according to claims 2, 7 or 8, in which (1) the volatile fraction of the residual gas is heated, compressed and then cooled under pressure in order to condense at least part of it; and (2) the condensed part is divided into at least two parts in order to thereby form a condensed stream and a second liquid stream. 37. The method according to claim 9, in which a more volatile stream of steam distillation is heated, compressed, cooled, and then combined with a stream of steam in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components. 38. The method according to claim 10, in which a more volatile stream of steam distillation is heated, compressed, cooled and then combined with a second stream of steam in order to form a volatile fraction of the residual gas containing the bulk of methane and lighter components. 39. Improvement according to claims 1 to 28, 32, 33, 37 or 38, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components and C2 components. 40. The method according to claims 1 to 28, 32, 33, 37 or 38, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components, components C2 and components C3. 41. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, said device having (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under pressure; 42. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes -27005326 (1) one or more second heat transfer means mutually connected to receive a natural gas stream and cool it under a pressure sufficient to partially condense it; 43. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means, interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a liquefied natural gas stream in which said device includes (1) one or more second heat exchange means interconnected in order to receive the natural gas stream and cool it under pressure; 44. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under a pressure sufficient to partially condense it; 45. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under a pressure sufficient to partially condense it; 46. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under pressure; 47. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, said device having (a) one or more first heat exchangers interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under a pressure sufficient to partially condense it; 48. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under a pressure sufficient to partially condense it; 49. A device for liquefying a stream of natural gas containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a stream of natural gas and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under pressure; 50. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under a pressure sufficient to partially condense it; 51. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under pressure; 52. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under a pressure sufficient to partially condense it; 53. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under pressure; 54. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means, interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and -35005326 (b) first expansion means connected to the first heat exchange means in order to receive a condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under a pressure sufficient to partially condense it; 55. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to to condense at least a portion of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes: 56. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat transfer means, interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under a pressure sufficient to partially condense it; 57. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under pressure; 58. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchangers interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under pressure in order to partially condense it; 59. A device for liquefying a stream of natural gas containing methane and heavier components of hydrocarbons, and in the specified device -39005326 (a) one or more of the first heat transfer means interconnected to receive a natural gas stream and cool it under pressure in order to condense at least a portion of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under pressure; 60. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under a pressure sufficient to partially condense it; 61. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under pressure; 62. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, said device having (a) one or more first heat exchange means, interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under a pressure sufficient to partially condense it; 63. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and -42005326 (b) first expansion means connected to the first heat exchange means in order to receive a condensed stream and expand it to a lower pressure in order to form said liquefied natural gas stream; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under pressure; 64. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein the device has (a) one or more of the first heat exchangers interconnected to receive a natural gas stream and cool it under pressure in order to to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under a pressure sufficient to partially condense it; 65. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, said device having (a) one or more first heat exchange means, interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under pressure; 66. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device includes (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under pressure in order to partially condense it; 67. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein the device has (a) one or more of the first heat exchangers interconnected to receive a natural gas stream and cool it under pressure in order to to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device mainly contains (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under pressure; 68. A device for liquefying a natural gas stream containing methane and heavier hydrocarbon components, wherein said device has (a) one or more of the first heat exchange means interconnected to receive a natural gas stream and cool it under pressure in order to in order to condense at least part of it and form a condensed stream; and (b) first expansion means connected to the first heat exchange means in order to receive the condensed stream and expand it to a lower pressure in order to form a stream of liquefied natural gas; moreover, the specified device mainly contains (1) one or more second means for heat exchange, mutually connected in order to receive a stream of natural gas and cool it under a pressure sufficient to partially condense it; 69. The device according to paragraphs 43, 44, 45, 67 or 68, comprising (1) means for compression connected to the distillation column in order to receive the volatile fraction of the residual gas and compress it; and (2) a first heat exchange means connected to the compression means in order to receive the compressed volatile fraction of the residual gas, the first heat exchange means adapted to cool the compressed volatile fraction of the residual gas under pressure in order to condense at least least part of it and thus form a condensed stream. 70. The device according to paragraph 41, comprising (1) a means for compression connected to the distillation column in order to receive the volatile fraction of the residual gas and compress it; 71. The device according to § 42, including (1) a means for compression connected to the distillation column in order to receive the volatile fraction of the residual gas and compress it; 72. The device according to item 46, comprising (1) a means for compression connected to the distillation column in order to receive the volatile fraction of the residual gas and compress it; 73. The device according to item 47 or 48, comprising (1) a means for compression connected to the distillation column in order to receive the volatile fraction of the residual gas and compress it; 74. The device according to 49, comprising (1) compression means connected to the distillation column in order to receive a more volatile stream of distillation steam and compress it; and (2) a combining means connected to a separation means and a compression means in order to receive a steam stream and a compressed more volatile distillation steam stream and combine them to form a volatile residual gas fraction containing a majority of methane and more light components. 75. The device according to item 50, including (1) means for compression, connected to the distillation column in order to receive a more volatile stream of steam distillation and compress it; and (2) a combining means connected to a separation means and a compression means in order to receive a second vapor stream and a compressed more volatile distillation vapor stream and combine them to form a volatile residual gas fraction containing a majority of methane and lighter components. 76. The device according to PP.51, 52, 55 or 56, comprising (1) compression means connected to contacting and separation means in order to receive the volatile fraction of the residual gas and compress it; and (2) a first heat exchange means connected to the compression means in order to receive the compressed volatile fraction of the residual gas, the first heat exchange means adapted to cool the compressed volatile fraction of the residual gas under pressure in order to condense at least least part of it and thus form a condensed stream. 77. The device according to paragraphs 53, 54, 57-65 or 66, comprising (1) compression means connected to combining means in order to receive the volatile fraction of the residual gas and compress it; and (2) a first heat exchange means connected to the compression means in order to receive the compressed volatile fraction of the residual gas, the first heat exchange means adapted to cool the compressed volatile fraction of the residual gas under pressure in order to condense at least least part of it and thus form a condensed stream. 78. The device according to paragraphs 43, 44, 45, 67 or 68, comprising (1) heating means connected to a distillation column in order to receive the volatile fraction of the residual gas and heat it; 79. The device according to paragraph 41, comprising (1) means for heating, connected to the distillation column in order to receive the volatile fraction of the residual gas and heat it; 80. The device according to item 42, including -48005326 (1) heating means connected to the distillation column in order to receive the volatile fraction of the residual gas and heat it; 81. The device according to item 46, comprising (1) means for heating, connected to the distillation column in order to receive the volatile fraction of the residual gas and heat it; 82. The device according to item 47 or 48, comprising (1) a means for heating connected to the distillation column in order to receive the volatile fraction of the residual gas and heat it; 83. The device according to 49, comprising (1) a means for heating connected to the distillation column in order to receive a more volatile stream of steam distillation and heat it; 84. The device according to item 50, including (1) means for heating, connected to the distillation column in order to receive a more volatile stream of steam distillation and heat it; 85. The device according to PP.51, 52, 55 or 56, comprising (1) a means for heating, connected to a means for contacting and separation in order to receive the volatile fraction of the residual gas and heat it; 86. The device according to paragraphs 53, 54, 57-65 or 66, comprising (1) means for heating, connected to means for combining in order to receive the volatile fraction of the residual gas and heat it; 87. The device according to paragraphs 41-68, 70, 71, 72, 74, 75, 79, 80, 81, 83 or 84, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components and C ₂ components. 88. The device according to paragraphs 41-68, 70, 71, 72, 74, 75, 79, 80, 81, 83 or 84, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components, components C ₂ and components C3. 89. The method according to clause 29, in which the volatile fraction of the lighter components and components C ₂ . 90. The method according to claim 30, wherein the volatile fraction of the lighter components and C2 components. 91. The method according to p, in which the volatile fraction of the lighter components and components C2. 92. The method according to clause 34, in which the volatile fraction of the lighter components and components C ₂ . 93. The method according to clause 35, in which the volatile fraction of the lighter components and components With ₂ . 94. The method according to clause 36, in which the volatile fraction of the lighter components and components C ₂ . 95. The method according to clause 29, in which the volatile fraction of the lighter components, components C2 and components C3. 96. The method according to clause 30, in which the volatile fraction of the residual lighter components, components C2 and components C3. 97. The method according to p, in which the volatile fraction of the residual lighter components, components C2 and components C3. 98. The method according to clause 34, in which the volatile fraction of the residual lighter components, components C ₂ and components C ₃ . 99. The method according to clause 35, in which the volatile fraction of the residual lighter components, components C ₂ and components C ₃ . 100. The method according to clause 36, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components, components C ₂ and components C ₃ . 101. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components and components C2. 102. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components and components C2. 103. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components and components C2. 104. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components and components C ₂ . 105. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components and components C ₂ . residual residual residual residual residual residual residual gas gas gas gas gas gas gas gas contains the main contains the main contains the main contains the main contains the main contains the main part part part part part part methane, methane, methane, methane, methane, methane, methane, gas gas gas gas contains the main contains the main contains the main contains the main part part part part methane, methane, methane, methane, -50005326 106. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components and components C ₂ . 107. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components and components C2. 108. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components and components C2. 109. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components, components C ₂ and components C ₃ . 110. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components, components C ₂ and components C ₃ . 111. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components, components C ₂ and components C ₃ . 112. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components, components C2 and components C3. 113. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components, components C2 and components C3. 114. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components, components C2 and components C3. 115. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components, components C2 and components C3. 116. The device according to p, in which the volatile fraction of the residual gas contains the bulk of methane, lighter components, components C2 and components C3.