RU2637242C1 - Method for regeneration of drying process adsorbent and purification of hydrocarbon gas (versions) and system for its implementation - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: method for regeneration of adsorbent includes sequential heating and cooling of adsorbent by blowing with dry stripped gas as regeneration gas and cooling gas which is produced by isolating hydrocarbons C_2+higher or C_3+higher from dried and purified hydrocarbon gas during its low-temperature processing, subsequent compression and cooling in a booster compressor station, heating cooling gas after adsorbent cooling stage to produce hot regeneration gas and supplying it to adsorbent regeneration. According to the first version a portion of dry gas flow is used as cooling gas which is taken after cooling in the booster compressor station in an amount equal to the total amount of gas required for regeneration of adsorbent, and when the present temperature is reached during the adsorbent cooling stage, the supply of cooling gas is stopped, at the same time the supply of hot dry stripped flow portion taken after compression in the booster compressor station in amount equal to the amount of cooling gas is provided at the regeneration gas production stage. According to the second version, a portion of dry stripped gas flow is used as cooling gas which is taken after cooling in the booster compressor station calculated in the amount providing cooling of adsorbent during the cooling-regeneration cycle, at that after adsorbent cooling stage, cooling gas is connected to a portion of hot dry stripped gas flow continuously taken after compression in the booster compressor station in the amount providing regeneration of adsorbent. A system for implementing the method is also proposed.

EFFECT: invention makes it possible to reduce energy costs for conducting adsorbent regeneration process.

3 cl, 1 dwg

Description

The invention relates to techniques and technologies for adsorption drying and purification of hydrocarbon gases and can be used in the oil and gas refining and petrochemical industries in the design and construction of gas treatment and refining facilities, petrochemical refining (gas processing plants, refineries, gas and chemical plants, LNG production) incorporating adsorption preparation plants gas.

In the processes of preparation and processing of hydrocarbon gases and liquids, where adsorption processes are used (drying or drying / purification), the main energy costs are the regeneration of the adsorbent, which, as a rule, is carried out at a temperature of 180-320 ° C by blowing the selected adsorber undergoing regeneration regeneration gas (hydrocarbon gas, inert gas). For heating the regeneration gas, for example, technological furnaces, flue gas heat from turbine compressor drives, and electric heating are used.

A known method of regenerating an adsorbent for a process for drying a hydrocarbon gas is described in a hydrocarbon gas preparation unit (see RF patent for the invention No. 2381822, B01D 53/04, published on 02/20/2010 in OB No. 5), comprising sequential purging of the zeolite with a part of the dry topped gas stream (SOG) as regeneration gas and cooling gas, which is obtained by separating C _{3 +} hydrocarbons from _above dry hydrocarbon gas when the low temperature processing, heating of the cooling gas after purging the adsorbent and feed it as aza regeneration of the adsorbent for regeneration, followed by cooling the spent regeneration gas and the direction of its further use.

Common features of the known and proposed methods are:

- sequential heating and cooling of the adsorbent by blowing with a heated regeneration gas and a cooling gas, respectively;

- the use as a regeneration gas and a cooling gas of a part of the COG stream, which is obtained by the separation of C _{3 + higher} hydrocarbons from dried hydrocarbon gas during its low-temperature processing;

- heating the cooling gas after the cooling stage of the adsorbent to obtain hot regeneration gas and its supply to the regeneration of the adsorbent.

The disadvantage of this method is the significant energy consumption for heating the regeneration gas in the heating apparatus, which is especially typical for adsorption drying (treatment) of gases with a capacity of more than 1 billion m ³ / year.

The closest in technical essence and the achieved result is a method of zeolite regeneration of the process of drying and purification of natural gas from sulfur compounds (see RF patent No. 2159663, IPC ⁷ B01D 53/02, B01D 53/26, publ. 11/27/2000), including sequential purging the zeolite with a heated regeneration gas and a cooling gas, which are dried and purified from sulfur compounds natural gas, and the cooling gas is subjected to low-temperature condensation and rectification with the release of hydrocarbons before purging the zeolite With _{2 + higher} residual amounts of sulfur compounds and moisture, the remaining methane fraction is compressed and purified from compressor oil vapor, and after purging the zeolite in the cooling stage, it is additionally heated and used as a regeneration gas.

Common features of the known and proposed methods are:

- sequential heating and cooling of the adsorbent by blowing with a heated regeneration gas and a cooling gas, respectively;

- use as a regeneration gas and a cooling gas SOG, which is obtained by separating hydrocarbons C _{2 + higher} from dried and purified hydrocarbon gas during its low-temperature processing, subsequent compression and cooling in a booster compressor station (DCS);

- heating the cooling gas after the cooling stage of the adsorbent to obtain hot regeneration gas and its supply to the regeneration of the adsorbent.

The disadvantages of this method are:

- lack of use of heat of the regeneration gas for heating the cooling gas before feeding the regeneration gas to the heating furnace;

- significant fluctuations in the temperature of the cooling gas at the cooling stage of the corresponding adsorber (from 280-180 ° C to 60-40 ° C) before entering the regeneration gas heating furnace, affecting the flow of fuel gas and automatic control of the furnace;

- an increase in the heat load on the regeneration gas heating furnace and an increase in fuel gas consumption due to the lack of heat recovery of the regeneration gas;

- increased energy load on the cooling unit for the regeneration exhaust gas (electricity, water).

In practice, various schemes for heating the regeneration gas are used — using (recovering) the heat of the regeneration gas and without recovering heat — by supplying the cooling gas of the adsorbers directly to the furnace for heating the regeneration gas.

The regeneration gas heating circuit without heat recovery was used in a well-known installation for drying and purifying natural gas from sulfur compounds (see RF patent for utility model No. 12904, IPC ⁷ B01D 53/02, publ. 27.02.2000), which contains adsorbers with zeolite, the top of which is connected to the supply lines of raw gas and exhaust gases of regeneration and cooling, and the bottom - to the lines of exhaust gas and supply of gases of regeneration and cooling, the heating gas of the regeneration gas connected to the exhaust line of the cooling gas, while the cooling gas supply line is connected and with a line for the removal of commercial gas and is equipped with a series-installed block of low-temperature condensation and rectification, a booster compressor station and a vapor recovery unit for compressor oil, the outlet of which is connected to the gas supply line for cooling the adsorbers.

Common features of the known installation and the present invention are:

- a block of adsorption drying and gas purification, containing adsorbers with an adsorbent, the top of which is connected to the supply lines of raw gas and exhaust gases of regeneration and cooling, and the bottom - to the lines of drainage of dried and purified gas and supply of regeneration and cooling gases;

- a regeneration gas heating furnace connected to a regeneration gas supply line to the adsorbers;

- a low-temperature gas processing unit, connected to the drainage line of the dried and purified gas and equipped with drainage lines of dry stripped gas (SOG) and a wide fraction of light hydrocarbons (BFLH);

- Booster compressor station (DKS), equipped with lines for supplying and discharging SOG.

The disadvantages of the known installation are:

- lack of use of heat of the regeneration gas for heating the cooling gas before feeding the regeneration gas to the heating furnace;

- significant fluctuations in the temperature of the cooling gas at the cooling stage of the corresponding adsorber (from 280-180 ° C to 60-40 ° C) before entering the regeneration gas heating furnace, affecting the flow of fuel gas and automatic control of the furnace;

- an increase in the heat load on the regeneration gas heating furnace and an increase in fuel gas consumption due to the lack of heat recovery of the regeneration gas;

- increased energy load on the cooling unit for the regeneration exhaust gas (electricity, water).

The heating gas regeneration gas with heat recovery was used in a hydrocarbon gas preparation unit (see RF patent for invention No. 2381822, B01D 53/04, published on February 20, 2010 in OB No. 5), which is the closest in technical essence and the achieved result to the proposed invention. A known installation includes a gas adsorption drying unit connected to a compressed gas supply line from a feed compressor, containing adsorbents filled in parallel with adsorbent, with supply lines of raw gas and drainage of dried gas, cooling gas supply and exhaust lines, and regeneration gas supply and exhaust lines, booster compressor and regeneration unit. The installation is also equipped with a low-temperature gas treatment unit, the input of which is connected to the exhaust gas line of the adsorbers, and the output - to the inlet of the booster compressor, as well as with the supply line of cooling gas to the adsorbers. In addition, the installation is equipped with a regeneration exhaust gas preparation unit, including a regeneration exhaust gas purification (separation) unit installed on the regeneration gas exhaust line and a membrane separation unit connected to the gas supply line to the booster compressor and to the raw gas supply line to the raw material compressor.

Common features of the known installation and the present invention are:

- an inlet separator installed on the raw gas supply line;

- a gas adsorption drying unit containing parallel-connected adsorbers filled with a sorbent, with raw gas supply and exhaust gas removal lines, cooling gas supply and exhaust lines and regeneration gas supply and exhaust lines;

- a regeneration and cooling unit comprising a regeneration gas filter, a cooling gas filter, a regenerative heat exchanger, a heating apparatus, a cooling apparatus and a regeneration exhaust gas separator;

- a cooling gas exhaust line is connected in series with a cooling gas filter, a regenerative heat exchanger, and a heating apparatus;

- a regeneration gas exhaust line is connected in series with a regeneration gas filter, a regenerative heat exchanger, a cooling apparatus, and a regeneration exhaust gas separator;

- a low-temperature gas processing unit connected to the drainage line of dried and purified gas and equipped with SOG and NGL exhaust lines;

- a booster compressor equipped with lines for supplying and discharging SOG.

A disadvantage of the known installation is the significant energy consumption for heating the regeneration gas in the heating apparatus, which is especially typical for gas adsorption drying (purification) plants with a capacity of more than 1 billion m ³ / year.

The technical task of the invention is to reduce energy costs for the process of regeneration of the adsorbent.

The stated technical task according to the first embodiment of the inventive method of adsorbent regeneration for the process of drying and purifying hydrocarbon gas, which includes sequential heating and cooling of the adsorbent by blowing dry stripped gas as a regeneration gas and a cooling gas, which is obtained by separating hydrocarbons C _{2 + above} or C _{3 + above} from the dried and purified hydrocarbon gas during its low-temperature processing, subsequent compression and cooling in a booster compressor station, heating the cooling gas after the stage of cooling the adsorbent to obtain hot regeneration gas and its supply to the regeneration of the adsorbent is solved due to the fact that part of the dry stripped gas stream, which is selected after cooling in the booster compressor station in an amount equal to the total amount of gas required, is used as the cooling gas for regeneration of the adsorbent, and when the desired temperature is reached at the stage of cooling the adsorbent, the supply of cooling gas is stopped and, at the same time, the recovery gas they feed a portion of the flow of hot dry stripped gas taken after compression in the booster compressor station in an amount equal to the amount of cooling gas.

The stated technical task according to the second variant of the inventive method of adsorbent regeneration for the process of drying and purifying hydrocarbon gas, which includes sequential heating and cooling of the adsorbent by blowing dry stripped gas as a regeneration gas and a cooling gas, which is obtained by separating hydrocarbons C _{2 + above} or C _{3 + above} from the dried and purified hydrocarbon gas during its low-temperature processing, subsequent compression and cooling in a booster compressor station, heating the cooling gas after the stage of cooling the adsorbent to obtain hot regeneration gas and its supply to the regeneration of the adsorbent, it is decided that part of the flow of dry stripped gas, which is taken after cooling in the booster compressor station in the calculated amount that ensures the cycle time, is used as the cooling gas cooling-regeneration cooling of the adsorbent, while after the stage of cooling the adsorbent, the cooling gas is connected to a part of the flow of hot dry stripped gas, constantly taken after compression in the booster compressor station in an amount that provides a total regeneration of the adsorbent.

The stated technical task according to the inventive adsorbent regeneration system, including an inlet separator installed on a raw gas supply line, an adsorption drying and gas purification unit, containing adsorbents filled in parallel with a sorbent, with raw gas supply and exhaust lines for dried and purified gas, and supply and exhaust lines gas cooling and regeneration gas supply and exhaust lines, a regeneration and cooling unit comprising a regeneration gas filter, a cooling gas filter, a regenerative heat exchange nickname, regeneration gas heating furnace, cooling apparatus and a regeneration exhaust gas separator, a low-temperature gas processing unit connected to a drain line of dried and purified gas and equipped with lines for draining dry stripped gas and for removing a wide fraction of light hydrocarbons, a booster compressor equipped with supply and exhaust lines dry stripped gas is solved due to the fact that the removal of dry stripped gas after the booster compressor is connected to an additionally installed air cooler m and further to the backbone of commercial gas, wherein the dry gas outlet downstream of the air cooler provided with a further tap, coupled to the cooling gas supply line in the adsorbers, and the withdrawal of dry gas after the booster compressor is provided with an additional tap connected to the input of the recuperative heat exchanger.

The technical result of the invention consists in reducing energy costs for the process of regeneration of the adsorbent.

The claimed combination of features of the proposed method of regeneration of the adsorbent according to the first and second options allows, due to the additional removal of hot SOG after the booster compressor, equipped with the necessary C&A (control and automation) and valves, to significantly reduce energy costs (fuel gas) at the stage of regeneration of the adsorbent, which depending on the use of the first or second option can be up to 50%.

The claimed combination of features of the proposed adsorbent regeneration system allows by connecting the additional exhaust gas after the air cooler with the supply line of cooling gas to the adsorbers, and the additional exhaust gas after the booster compressor with the input of the regenerative heat exchanger:

- increase the temperature of the gas at the outlet of the regenerative heat exchanger and reduce the heat load on the furnace, while the flow of fuel gas to the regeneration gas heating furnace will decrease by 20-50%;

- due to less temperature fluctuations after the recuperative heat exchanger, carry out softer and more stable automatic regulation of the operation of the regeneration gas heating furnace to maintain the required temperature of the regeneration gas at the outlet of the furnace;

- when supplying hot gases after the booster compressor to the regeneration system, reduce the energy load on the air cooler for cooling the SOG by 5-15% (of the amount of regeneration gas per process) due to the selection of hot SOG after the booster compressor.

The drawing shows a schematic flow diagram of the proposed adsorbent regeneration system.

The adsorbent regeneration system includes an inlet separator 1 for separating liquid connected to the adsorption drying and gas purification unit.

The adsorption drying and gas purification unit contains parallel-connected adsorbers 2 filled with adsorbent. The number of adsorbers 2 in the circuit may be 3, 4 or 6 (if necessary). Each adsorber 2 is equipped with:

- line 3 feed gas,

- line 4 of the drain of dried and purified gas,

- line 5 supply gas regeneration,

- line 6 exhaust gas regeneration,

- line 7 for supplying cooling gas,

- line 8 of the exhaust gas cooling.

Line 4 drainage of dried and purified gas is connected to the filter 9.

The installation is equipped with a regeneration and cooling unit comprising a regeneration gas filter 10, a cooling gas filter 11, a regenerative heat exchanger 12, a regeneration gas heating furnace 13, and cooling apparatuses — an air cooler 14 and a water cooler 15 (if necessary) and a regeneration exhaust gas separator 16.

The regeneration gas exhaust line 6 is connected to a regeneration gas filter 10, a regenerative heat exchanger 12, an air cooler 14, a water cooler 15 and a regeneration exhaust gas separator 16 arranged in series. The regeneration exhaust gas separator 16 is provided with exhausts of the regeneration exhaust gas and condensed water.

The cooling gas exhaust line 8 is connected to a cooling gas filter 11, a recuperative heat exchanger 12, and a regeneration gas heating furnace 13 connected in series. The output of the furnace 13 for heating the regeneration gas is connected to a line 5 for supplying regeneration gas to the adsorbers 2.

The installation is equipped with a low-temperature gas processing unit 17 connected to the drained and purified gas exhaust line 4 after the filter 9. The low-temperature gas processing unit 17 is equipped with an SOG exhaust line 18 and an NGL exhaust line 19.

The installation is equipped with a booster compressor station (BCS), including a booster compressor 20 and an air cooler 22.

The booster compressor 20 is equipped with an SOG supply connected via line 18 to the low-temperature gas processing unit 17 and an SOG outlet connected via line 21 with an air cooler 22. If necessary, the booster compressor 20 can be equipped with a compressor oil vapor recovery unit (not shown).

The removal of the SOG from the air cooler 22 via line 23 is connected to a gas line (not shown).

The SOG exhaust line 23 after the air cooler 22 is equipped with an additional outlet, which is connected via a line 24 to the cooling gas supply line 7 to the adsorbers 2.

The exhaust gas exhaust line 21 after the booster compressor 20 is equipped with an additional exhaust, which is connected via line 25 to the input of the regenerative heat exchanger 12.

The system is also equipped with the necessary pipelines, shut-off and control valves and control and automation equipment (not shown).

The system works as follows (as an example, a diagram with four adsorbers is shown).

The feed gas with a temperature of 20-45 ° C and a pressure of 2.0-10.0 MPa after separation of the liquid in the inlet separator 1 enters through line 3 to the unit for adsorption drying and purification of hydrocarbon gas for drying the gas and its purification from acidic components. In this case, two adsorbers are in the adsorption cycle, one in the adsorbent regeneration cycle and one in the cooling cycle. The cycles of regeneration and cooling are 6 hours each, the adsorption cycle is 12 hours. The temperature of the regeneration gas is 200-320 ° C. The temperature in the adsorber at the end of the regeneration cycle is 180-300 ° C.

The dried and purified gas through line 4 enters the filter 9, in which the adsorbent dust entrained from the adsorbers is captured, and then sent to the low-temperature gas processing unit 17.

In block 17 of low-temperature gas processing due to lowering the pressure and lowering the temperature, part of the dried and purified gas condenses and SOG and NGL are released from it. BFLH through line 19 is sent for further processing, and LOG through line 18 with a pressure of 1.8-4.0 MPa is sent to compression in a booster compressor 20.

After the booster compressor 20, most of the COG stream with a temperature of 140-220 ° C via line 21 is fed to the air cooler 22 for cooling, and the other part of the COG stream through line 25 is sent to a regenerative heat exchanger 12 and then to the furnace 13.

In the air cooler 22, the SOG is cooled to a temperature of 30-45 ° C, after which the main part of the SOG stream through line 23 is sent to the commercial gas line, and the remaining part of the SOG stream through line 24 is sent as cooling gas to the adsorber 2, which is in the cooling mode .

The cooling gas enters the adsorber 2 through line 7 and, after exiting the adsorber 2 through line 8, is directed to the filter 11, where it is cleaned of adsorbent dust, and then enters the annulus of the recuperative heat exchanger 12, in which it is heated by a hot flow of regeneration gas leaving the line 6 from the adsorber 2, which is in regeneration mode, after which it enters the furnace 13.

The heated gas stream from the furnace 13 as a regeneration gas enters through the line 5 for regeneration of the adsorbent into the adsorber 2, which is in the regeneration mode. Saturated with moisture, the regeneration exhaust gas through line 6 through the filter 10 enters the recuperative heat exchanger 12, in which it transfers its heat to the cooling gas stream entering the regenerative heat exchanger via line 8. Next, the regeneration gas is cooled in the air cooler 14 and (if necessary) the water cooler 15 and then sent to the separator 16 to separate the exhaust gas regeneration and condensed water. The exhaust gas from the regeneration is sent for disposal by one of the known methods, and the condensed water is discharged into the drain.

The method of regeneration of the adsorbent of the drying and gas purification process is as follows.

In accordance with the first embodiment, the cooling gas through line 24 in an amount of 5-15% of the COG stream (corresponding to the usual gas flow rate for cooling and regeneration in existing and known adsorbent regeneration systems) with a temperature of 30-45 ° C is supplied to the adsorber 2 located in cooling mode. With the duration of the cooling and regeneration stages of 6 hours (normal operation), it takes 1.5-2 hours to cool the adsorber and adsorbent before the adsorption stage. When the adsorber 2 reaches the set temperature of 40-60 ° C, the automation and control system smoothly shut off (with the corresponding valve) the cooling gas supply line 24 and at the same time open the hot SOG supply line 25 after the booster compressor. Hot SOG in the amount of 5-15% of the total SOG stream with a temperature of 140-220 ° C is sent to the recuperative heat exchanger 12, thus replacing the cooling gas previously supplied to the recuperative heat exchanger 12 through line 8.

In accordance with the second option, the calculated (in accordance with the well-known practice of commercial operation of adsorption drying / gas purification plants) amount of gas required to cool the adsorber (20-40% of the amount of cooling and regeneration gases) is taken after cooling in the air cooler 22 and along the line 24 is sent to the cooling gas supply line 7 to the adsorber 2, which is in the cooling stage. An additional amount of gas taken after compression in the booster compressor 20 in an amount that ensures the total regeneration of the adsorbent (60-80% of the amount of regeneration gases) is fed through line 25 to the recuperative heat exchanger 12 along with the flow of cooling gas entering the recuperative heat exchanger 12 through the line 8.

In both cases, the supply of hot COH after the booster compressor with a temperature of 140-220 ° C will increase the temperature of the gas entering and leaving the recuperative heat exchanger 12 and supplied to the heating to the required regeneration temperature in the furnace 13. At the same time, the heat load on the regeneration gas heating furnace 13 is reduced. , and, consequently, the amount of fuel gas for heating the regeneration gas is reduced by 20-50%. The energy effect within the specified limits will increase with an increase in the required temperature of regeneration of the adsorbent, which provides deeper drying / purification of gas, which is especially important in the processes of low-temperature gas processing and LNG production.

For examples, the following initial data on an existing industrial gas dehydration plant are given:

Based on the calculations according to well-known formulas, we determine the total amount of heat that must be introduced for the regeneration of zeolite Q _tr :

- heat for heating the adsorbent: Q _load.ad-ta = 2340 thousand kcal.

- heat for heating adsorbed water and desorption of water from the pores of the zeolite: Q _des. = 4321 thousand kcal.

- heat for heating the adsorber metal: Q _load.ad-pa = 1591 thousand kcal.

- heat loss to the environment: Q _sweat. ~ 413 thousand kcal. ΣQ _tr = 2340 + 1591 + 4321 + 413 = 8665 thousand kcal.

In a similar way, the required amount of heat removed is determined at the stage of cooling the adsorbent from 280 ° C to 50 ° C: Q _{cooling add} = 2070 thousand kcal. The amount of heat to cool the walls of the adsorber to 50 ° C: Q _{cooling ad-ra} = 710 thousand kcal.

The total amount of waste heat in the cooling step: ΣQ _OHL = 2780 thousand kcal..

The remaining components of the heat consumption required during regeneration of the adsorbent are absent during its cooling.

As a result, the amount of heat removed during the cooling stage of the process is: ΣQ _cool. / ΣQ _tr = 2780/8665 = 32.0% of the amount of heat required for regeneration.

By well-known formulas determine the amount of regeneration gas having a temperature of 300 ° C, for which the regeneration cycle will tys.kkal 8665: V _b = 12 thousand m ³ / h (~ 9000 kg / h), which is 12/119 ~ 10.0% of the gas drained at the installation.

Thus, when the cooling and regeneration stages are 6 hours each (normal operation), to cool the adsorbent and adsorber to a temperature of 50 ° С before the adsorption stage, it is necessary: 6 hours 0.32 = 2 hours. In this case, after 2 hours the temperature of the cooling gas before the recuperative heat exchanger 12 will be 50-60 ° C, and after it at the inlet to the furnace 13 at a temperature of the regeneration exhaust gas (line 6) at the level of 270-280 ° C will be 120-140 ° C.

Example 1

The beginning of the cooling-regeneration cycles is carried out according to the usual scheme. As the cooling gas, a part of the COG stream is used, which is taken along line 24 after cooling in the air cooler 22. After the cooling gas is supplied to the adsorber with a temperature of 30-45 ° C in an amount of 12 thousand m ³ / h for 2 hours, the adsorber with adsorbent it is cooled to a temperature of 40-60 ° C and is ready for the adsorption stage. When the set temperature (40-60 ° C) is reached, the supply of cooling gas is stopped, for which the automation and control system smoothly cut off line 24 with the corresponding valve. Simultaneously with the cessation of the supply of cooling gas, line 25 for supplying the hot COG stream taken after compression in the booster compressor 20 opens A hot stream of SOG with a temperature of 140-220 ° C in an amount of 12 thousand m ³ / h is sent to the input of the regenerative heat exchanger 12.

For further calculations of fuel gas savings, the following data are accepted.

The temperature of the cooling gas (~ 12 thousand m ³ / h) in front of the regenerative heat exchanger 12 after 2 hours will be 50-60 ° C, and after it - 120-140 ° C. To reheat the gas in furnace 13 over the next 4 hours to a temperature of 300 ° C, ~ 890000 kcal / h of heat or ~ 95 kg / h, or ~ 134 m ³ / h of fuel gas will be required.

After switching and supplying hot gas through line 25 with a temperature of 140 ° C to the input of the recuperative heat exchanger 12, the gas temperature after the recuperative heat exchanger 12 will be ~ 200 ° C. To preheat the gas in furnace 13 to a temperature of 300 ° C, ~ 60 kg / h or ~ 85 m ³ / h of fuel gas will be required.

When the temperature of the hot gas in front of the recuperative heat exchanger is ~ 200 ° C, its temperature in front of the furnace 13 will be ~ 240 ° C. To preheat the gas in the furnace 13 to a temperature of 300 ° C, ~ 35 kg / h or ~ 50 m ³ / h of fuel gas will be required.

Considering that the time for reducing fuel gas consumption is 4 hours out of 6 hours needed for regeneration, fuel gas savings will be:

- at a gas temperature along line 24 at a level of 140 ° C: (134-85) / 134 4 / 6≈24%

- at a gas temperature along line 24 at a level of 200 ° C: (134-50) / 134 4 / 6≈42%

Example 2

As the cooling gas, a part of the COG stream used is directed along line 24 after cooling in the air cooler 22 in an amount of 20-40% of the total amount of gas required for the cooling-regeneration stages (in this example, this amount is ~ 33% of 12 thousand .m ³ / h, i.e. ~ 4.0 thousand m ³ / h). This amount of gas provides cooling of the adsorber with the adsorbent to 50-60 ° C for 6 hours.

The remaining amount of gas is 60-80% of the total amount of gas required for the cooling-regeneration stages (in this example, this amount is ~ 66% of 12 thousand m ³ / h, i.e. ~ 8.0 thousand m ³ / h) with a temperature of 140-220 ° C is fed through line 25 to the input of the regenerative heat exchanger 12.

When the temperature of the hot gas supplied through line 25 to the input of the regenerative heat exchanger 12 is 140 ° C (in this example, 8.0 thousand m ³ / h for 6 hours), the average gas temperature after the regenerative heat exchanger 12 will be ~ 185 ° C. To heat the gas in the furnace 13 to a temperature of 300 ° C, ~ 70 kg / h or ~ 100 m ³ / h of fuel gas will be required. The fuel gas savings in this case will be: (134-100) / 134≈25%

When the temperature of the hot gas supplied through line 25 to the input of the recuperative heat exchanger 12 is 200 ° C, the gas temperature after the recuperative heat exchanger 12 will be ~ 220 ° C. To preheat the gas in furnace 13 to a temperature of 300 ° C, ~ 47 kg / h or -66 m ³ / h of fuel gas will be required. The fuel gas savings in this case will be: (134-66) / 134≈51%.

Thus, as can be seen from examples 1 and 2, in comparison with the known methods of regeneration of the adsorbent, the proposed method allows to reduce the energy costs of the regeneration of the adsorbent due to the reduction of the heat load on the heating furnace and the amount of fuel gas for heating the regeneration gas by 20-50% .

Claims (3)

1. A method of regenerating an adsorbent for a process of drying and purifying a hydrocarbon gas, comprising sequentially heating and cooling the adsorbent by blowing dry stripped gas as a regeneration gas and a cooling gas, which is obtained by separating hydrocarbons C _{2 + above} or C _{3 + above} from dried and purified hydrocarbon gas at its low-temperature processing, subsequent compression and cooling in a booster compressor station, heating the cooling gas after the stage of cooling the adsorbent to obtain hot gas regene cation and its supply to the regeneration of the adsorbent, characterized in that as the cooling gas use part of the flow of dry stripped gas, which is taken after cooling in the booster compressor station in an amount equal to the total amount of gas required for regeneration of the adsorbent, and when the set temperature is reached stages of adsorbent cooling, the cooling gas supply is stopped and at the same time, part of the flow of hot dry stripped gas taken from after compression in the booster compressor station in an amount equal to the amount of cooling gas. 2. A method of regenerating an adsorbent for a process of drying and purifying a hydrocarbon gas, comprising sequentially heating and cooling the adsorbent by blowing dry stripped gas as a regeneration gas and a cooling gas, which is obtained by separating hydrocarbons C _{2 + above} or C _{3 + above} from dried and purified hydrocarbon gas at its low-temperature processing, subsequent compression and cooling in a booster compressor station, heating the cooling gas after the stage of cooling the adsorbent to obtain hot gas regene cation and its supply to the regeneration of the adsorbent, characterized in that as the cooling gas use part of the flow of dry stripped gas, which is taken after cooling in the booster compressor station in the calculated amount, which ensures the adsorbent during the cooling-regeneration cycle, and after the cooling stage the adsorbent cooling gas is combined with a part of the flow of hot dry stripped gas, which is constantly taken after compression in the booster compressor station in an amount which regenerates the adsorbent. 3. The adsorbent regeneration system, including an inlet separator installed on the raw gas supply line, an adsorption drying and gas purification unit, containing adsorbents filled in parallel with the adsorbent, with raw gas supply and drainage lines for dried and purified gas, and cooling gas supply and exhaust lines and regeneration gas supply and exhaust lines, a regeneration and cooling unit comprising a regeneration gas filter, a cooling gas filter, a regenerative heat exchanger, a regeneration gas heating furnace, cooling units a regeneration waste gas separator and separator, a low-temperature gas processing unit connected to a drain line of dried and purified gas and equipped with lines for draining dry stripped gas and for discharging a wide fraction of light hydrocarbons, a booster compressor equipped with lines for supplying and discharging dry stripped gas, characterized in that the discharge of dry stripped gas after the booster compressor is connected to an additionally installed air cooler and then to the commercial gas line, while after the air cooler is equipped with an additional outlet connected to the line for supplying cooling gas to the adsorbers, and the outlet of dry topped gas after the booster compressor is equipped with an additional outlet connected to the inlet of the regenerative heat exchanger.

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