JPH034278B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to the removal of light oils from solid granules, and in particular, water-solid liquids are mixed with light fluidized oils and subjected to dehydration treatment by thermal evaporation. Removal of residual light oil from solids obtained in such processes.

BACKGROUND OF THE INVENTION Recovery of clean water from aqueous solutions and dispersions and economical disposal of waste solids is a recognized need. Also of great concern is the need to recover clean water and valuable solids from aqueous solutions and dispersions. Ideally, methods and equipment for recovering water from water-solid systems should provide ease of processing, avoidance of contamination, economical operation and hygienic handling of all components and must produce clean water.
Additionally, in the process of recovering clean water, it is desirable to obtain solid and liquid by-products that are of value in themselves or that can be used to enhance the economics of the process.

For the purposes of this invention, the term "water-solids or aqueous solids" includes suspensions, dispersions, solutions, mixtures and all other forms in which solids are fluidly associated with water. Used to include.

In Applicant's U.S. Patent No. 3,855,079,
A method and apparatus for mixing a water-solid liquid with a relatively non-volatile fluidizing oil to form a mixture and dewatering the mixture by thermal evaporation is disclosed. The substantially anhydrous solids in the fluidized oil formed are then
It is separated into an oil phase and a solid phase. However, the solids have a significant amount of fluidizing oil adsorbed thereon, which contaminates the solids and, if not recovered, is lost to the process and reduces economics. The fluidized oil-supported solid is therefore subjected to a subsequent extraction step using a relatively volatile water-immiscible gas oil. The gas oil-loaded solids are then brought into direct contact with blown steam to effect the removal of residual water-immiscible gas oil from the solids.

In our U.S. Pat. No. 4,270,974, the water-solid liquid is a low viscosity, relatively volatile
water-immiscible light fluidizing oils are mixed to form a mixture, the mixture being subjected to a dehydration treatment by thermal evaporation;
A method and apparatus are described whereby substantially all of the water and at least a portion of the light oil are evaporated and subsequently recovered. The light fluidized oil is then largely separated from the solids. The solids carrying residual light fluidized oil are brought into direct contact with the blown steam to effect removal of the residual light fluidized oil therefrom.

SUMMARY OF THE INVENTION Broadly stated, the methods and apparatus of the present invention include:
It consists of a series of stages and a systematic arrangement of equipment for separating light oil from its supporting solids. In particular, the present invention relates to the removal of residual light oils from solids obtained from the dewatering of mixtures of water-solids and fluidized oils. In one embodiment, a water-solid liquid is slurried with a relatively non-volatile oil to form a mixture, and the mixture is dehydrated by thermal evaporation. The substantially anhydrous solid slurry in the fluidized oil is then separated into an oil phase and a solid phase. Since the solid has a significant amount of relatively non-volatile fluidizing oil sorbed thereon, the solid is subjected to an extraction step using a relatively volatile light oil. In another embodiment of the invention, the water-solid liquid is mixed with a low viscosity, relatively volatile, water-immiscible light fluidizing oil and the resulting mixture is dehydrated by thermal evaporation. , whereby substantially all of the water and at least a portion of the light fluidized oil are vaporized and subsequently recovered. The light fluidized oil is then largely removed from the solids. In any of the above embodiments, the method and apparatus of the present invention provides economical removal of residual light oil from the separated dry solids.

It is therefore an object of the present invention to provide a method and apparatus for separating light oil from the solids supporting it.

Another object of the invention is a method and method for the removal of residual light oils from solids obtained by dehydration of a mixture of a relatively volatile, water-immiscible light fluidizing oil and a water-solid liquid. The purpose is to provide equipment.

Another object of the present invention is to provide a method and apparatus for the removal of residual light oils from solids obtained by dehydration of a relatively non-volatile fluidizing oil mixture with a water-solid liquid. In this case, the anhydrous solids are separated from the non-volatile fluidizing oil and the residual fluidizing oil is extracted therefrom with a relatively volatile light oil.

Yet another object of the invention is to substantially dry a water-solid system from solids dehydrated in a fluidized oil medium.
It is an object of the present invention to provide a method and apparatus for recovering solids free of fluidized oil.

Another object of the present invention is to provide a method and apparatus for the recovery of clean water from water-solid liquids.

The above objects and others are achieved by the practice of the present invention. Generally speaking, under one aspect of the principle aspects of the invention, the invention provides: 1. Bringing a light oil-bearing solid into direct contact with a hot inert blowing gas, thereby causing thermal evaporation. 2. A method for separating light oil from solids associated therewith, comprising the steps of: 2) directing an effluent inert blowing gas containing light oil vapor away from the solids; Become.

The method comprises: 1. an oil separation means adapted to receive light oil-bearing solids; 2. means for generating a hot inert blow gas; and 3. from the hot inert blow gas generation means to the oil separation means. (4) a conduit extending from and through which the hot inert blowing gas is brought into direct contact with the light oil-bearing solids within the oil separation means; and a discharge means extending from said oil separation means for discharge.

Thus, the present invention provides a method and apparatus for separating light oil from its supporting solids. In particular, the present invention provides a method and apparatus for the removal of residual light oils from solids obtained from the dewatering of a mixture of water-solids liquid and fluidizing oil. In a most preferred embodiment, the fluidizing oil is a relatively volatile, water-immiscible light oil. The present invention is characterized not only by the recovery of clean water from a water-solid system that is dehydrated in a light oil medium, but also by the recovery of residual light oil from the solids. The water-solid liquid is mixed with a low viscosity, relatively volatile, water-immiscible light fluidizing oil and the mixture is subjected to a dehydration stage by thermal evaporation to remove substantially all of the water and part of the light oil. remove part. The remainder of the light fluidized oil is then largely separated from the solids. The light fluidized oil-bearing solids are then brought into direct contact with a hot inert gas, referred to herein as a "blowing gas", in an oil separation stage. Direct contact of the light oil with hot inert blowing gas results in evaporation and separation of the oil from the solids. Unlike the processes disclosed in the aforementioned U.S. Pat. No major oil-water separation is required after condensation with steam.

DESCRIPTION OF THE EMBODIMENTS The process of the invention is characterized by the separation of light oils from solids associated therewith. In particular, the present invention relates to the removal of residual light oil from solids that have already been fully dehydrated in a fluidized oil medium. In one embodiment, the method includes mixing a water-solid liquid with a relatively volatile water-immiscible light fluidizing oil of low viscosity to maintain fluidity and flowability even after substantially all water content has been removed. the resulting mixture of solids, water and oil is then subjected to a thermal evaporative dehydration step, thereby evaporating substantially all of the water and at least a portion of the light fluidized oil. and subsequently collecting. Very dilute water-solid liquids may be concentrated by evaporation prior to mixing with light oils. Steam from the subsequent oil dehydration stage can be used to supply energy to this fluidized oil-free concentration stage of the evaporator system. Following dehydration, this light oil is largely separated from the solids.
The solids carrying the residual light fluidized oil are brought into direct contact with a hot inert blowing gas, whereby the residual light oil is removed by thermal evaporation.

In yet another embodiment of the invention, the method comprises:
By mixing a water-solid liquid and a relatively non-volatile oil,
obtaining a mixture that remains fluid and flowable after removal of substantially all the water content, and then subjecting the resulting mixture of solids, water and oil to a dehydration step by thermal evaporation to achieve evaporation. subsequently recovering a slurry comprising solids in water and substantially anhydrous oil. Very dilute water-solid liquids can be concentrated by evaporation prior to mixing with oil. A slurry containing solids in oil is subjected to a separation operation to produce a relatively non-volatile oil and solids carrying residual non-volatile oil. Residual fixed oils are substantially removed from the solids by extraction using light oils of relatively low viscosity. The light oil-bearing solids are then brought into direct contact with a hot inert blowing gas, whereby the relatively volatile light oil is removed by thermal evaporation.

An important step in the practice of the present invention is the direct contact of the light oil-bearing solid with the hot inert blowing gas, thereby effecting vaporization of the light oil. If the hot inert blowing gas is at a sufficiently high temperature, it will provide latent heat for vaporization of the light oil. On the other hand, if sufficient heat for the vaporization of the light oil is supplied from an external source, such as by means of a heating jacket, the light oil-supported solids can be brought into direct contact with the inert blowing gas at lower temperatures. sell.

By "light oil" is meant an organic liquid that is relatively fluid and at the same time relatively volatile. If the light oil is a fluidizing oil used for the dewatering of water-solid systems, it should also be water-immiscible. If a light oil is used only to extract relatively fixed oils from the solids associated with it, then
The light oil need not be water immiscible; it must be compatible with relatively fixed oils.
In accordance with the practice of the present invention, direct contact of the light oil-bearing solids with the hot inert blowing gas facilitates rapid and economical separation of the light oil from the solids.

In the practice of the present invention, a substantially anhydrous slurry containing solids in fluidized oil is subjected to a separation operation to recover the oil and the largely dry solids containing the sorbed fluidized oil. This can be accomplished by the action of gravity on the anhydrous slurry or by the application of static or dynamic mechanical pressure, whereby most of the oil is separated from the solids. In some cases, such as in foods, sewage sludge, fatty raw materials or slaughterhouse waste, the material itself contains appreciable amounts of oil apart from the fluidizing oil that may be added to it prior to the dewatering step. are doing. If the oil is a light oil, it is either evaporated during the dehydration and subsequently recovered or carried through the dehydration stage along with the main portion of the solids and added fluidized oil and separated from the dewatered slurry along with the added oil. If a substantially water-free slurry is subjected to a sufficiently efficient separation operation, oil will be produced in a proportion equal to or greater than the proportion previously added to the water-solid system. Good morning. If the oil associated with the water-solid system liquid is a heavy, relatively non-volatile oil and the fluidizing oil is a light, relatively volatile oil, it may be necessary to eventually Medium to light fluidized oils can be extracted from substantially dry solids, separated from light oils, and recovered. Alternatively, if the fluidizing oil is a heavy, relatively non-volatile oil, the associated oil becomes part of the fluidizing oil. After separation of the main portion of the heavy fluidized oil, the substantially dry solid containing the residual heavy oil is subjected to an extraction process using a light oil to remove the heavy oil therefrom.

It is generally desired that the entire deoiling and oil separation stage produce sufficient oil for reuse in the dewatering stage so that the process is self-sufficient in terms of fluidized oil requirements. Even more preferably, in some cases, the combination of oil separation and deoiling stages produces somewhat more oil than is required for the dewatering stage so that the process produces a net oil yield.

No matter how powerful the separation operation, e.g. press operation, of substantially anhydrous slurries containing solids in the fluidized oil, the recovered solids will sorb appreciable amounts of oil that, if not recovered, will lost to. Liquid-solid separation means for separating the fluidized oil from the solids are, for example, settling tanks, where separation takes place by gravity. Alternatively, the separation may be effected by a mechanical press of a static type, such as a reciprocating filter press, or advantageously by a dynamic separation device, such as a centrifuge. However, both static and dynamic presses can be used. Most of the oil is therefore pressed from the solids, for example in a centrifuge, and the oil is collected in a suitable reservoir and, if desired, made available for reuse in the process.

When a water-solid liquid is dehydrated in a light, relatively volatile fluidizing oil, it may initially contain light oil. In this case, the light oil can be recovered and reused in the dehydration stage. On the other hand, if the liquid originally contains heavy oil, it is
It may be separated from the substantially anhydrous solids by extraction with a light fluidized oil during the solids separation stage. If the separated oil is divided into its light and heavy oil components and only the light oil component is repeated as fluidized oil, a deduction is produced corresponding to a reduction in the heavy oil content of the dry solids. Things arise. On the other hand, if the separated oil consists entirely of light fluidized oil and the extracted heavy oil is repeated as fluidized oil, then the same proportion of heavy oil as is removed by the repeated fluidized oil is added to the dry solids. A state of equilibrium is achieved in which it is restored.
The product of subtraction is a substantially dry solid having substantially the same heavy oil content (on a water-free basis) as the original feed.

Since light fluidized oils can have low viscosity and low specific gravity (e.g. light oils from crude oil), the dewatered slurry from the evaporator is transferred to a settling tank so that more concentrated solids in the oil phase form a thick slurry. can be separated as Most of the oil remains at the top of the tank, from where it can be repeated into the process. The gravity separation operation described above does not require mechanical presses of static or dynamic type.

When a water-solid liquid is dehydrated in a heavy, relatively non-volatile fluidizing oil, the liquid may inherently contain light oil. In this case, the light oil is substantially removed along with the water during the dehydration stage and can be recovered therefrom. If the water-solids system originally contains heavy oil, this oil can be carried through the dewatering stage along with the solids and added fluidizing oil and expressed from the dewatered slurry along with the added oil.

No matter how aggressively the anhydrous slurry containing solids in fixed oil is pressed, the recovered solids will sorb appreciable amounts of fixed oil;
This will be lost to the process if not retrieved. In the practice of the present invention, fixed oil-bearing solids are extracted with relatively light oils to remove the fixed oil therefrom. Extraction may conveniently be carried out in a liquid-solid separation means which squeezes out the fixed oil from the solids. The liquid-solid separation means may be of a static type, such as a cage-type piston press, but it is advantageous to use dynamic separation means, such as a centrifuge. Most of the non-volatile oil is therefore squeezed out of the solids, for example in a centrifuge, and the oil is collected in a suitable sump where it can be reused in the process if desired. The fixed oil-bearing solids remaining in the centrifuge are then contacted internally with a relatively light oil and the relatively light oil containing the extracted fixed oil is then squeezed from the solids. The mixture of relatively light oil and extracted fixed oil can be separated by distillation, if desired, for example back into the evaporation system for the recovery of light oil from the fixed oil, and the individual components can be reused in the process. Ru.

The concentrated light oil-solid slurry or the light oil sorbed solids is then brought into direct contact with a hot inert blowing gas. The blowing gas, if hot enough, provides latent heat for vaporization of the light oil. Alternatively, an inert blowing gas at a lower temperature may be used in conjunction with external heat, such as from a steam jacket, to provide heat for vaporization of the light oil.

There are many advantages to using hot inert blowing gas over blowing steam in the deoiling stage. The use of hot inert blowing gas instead of blowing steam reduces the load on the steam generation capacity of the equipment system for enriching the water-solid liquid in the fluidized oil medium. In practice, the inert blowing gas may be a gaseous combustion product from a furnace used to generate steam for the equipment system. Another advantage of inert blowing gas over blowing steam is that the need for oil/water separation following condensation of the oil vapor removed during the deoiling stage is reduced. Yet another advantage is that inert blowing gas can provide more heat per unit volume than steam. At standard temperature and pressure, a volume of 22.4 is known to contain 1 gram molecular weight of gas. From this it can be seen that the higher the molecular weight of the gas, the greater the weight of the gas in a unit volume at a specified temperature and pressure. Therefore, by choosing an inert gas with a higher molecular weight than water (steam), a greater mass of inert gas than steam is contained in an equivalent volume at equivalent pressure and temperature. Therefore, at a certain temperature and pressure,
A unit volume of inert gas provides more heat (eg, BTU value) to vaporize sorbed light oils from dry solids than the same volume of steam.
The value of molecular weight x specific heat is larger for gas.
Moreover, the heavy oils present in the dry solids are not substantially evaporated. An example of an inert gas that has a higher molecular weight than water (molecular weight 18) is carbon dioxide (molecular weight 44)
It is.

The source of hot inert gas can vary widely. One source is gaseous combustion products from combustion devices such as furnaces. Alternatively, an inert gas such as nitrogen or carbon dioxide can be heated as in a combustion device and used as the blow gas.
In a device system for dewatering a water-solid liquid in a fluidized oil, the combustion device is conveniently a boiler and associated furnace used to generate steam for supplying heat of vaporization to an evaporator in the device system. It can be. Thus, the furnace in the system may be a source of hot gaseous combustion products used as blowing gas. These gaseous products may contain at least a small amount of air (non-stoichiometric combustion), but may still be considered inert for the purposes of the present invention. Alternatively, the furnace in the system may be a means for heating an inert gas, such as nitrogen or carbon dioxide, which may later be used as a blowing gas. Of course, the source of hot inert blowing gas need not be part of the equipment system for dewatering anhydrous solids in a fluidized oil medium. For example, a furnace not otherwise associated with the equipment system can be the source of gaseous combustion products used as the blow gas and can be the means for heating an inert blow gas such as nitrogen or carbon dioxide.

In most cases, the selection of the inert blowing gas brought into direct contact with the light oil-supported solids or concentrated light oil-solids slurry is not critical. However, in some applications, such as deoiling substances such as food for human consumption and animal feed, it is preferable to use inert gases such as nitrogen or carbon dioxide rather than gaseous combustion products. preferable.

Removal of light oil from the solids by direct contact with hot inert blowing gas is conveniently carried out in a deoiling unit which can be operated at atmospheric or subatmospheric pressure. A cooler blowing gas could be used at atmospheric pressure, in which case the blowing steam would require a vacuum. If desired, the deoiling equipment can be equally externally heated by a steam jacket. The hot inert blow gas is passed into a deoiler containing a concentrated light oil-solids slurry or light oil-bearing solids. Effluent blow gas and vaporized light oil are led out of the deoiler. The heavy oil present in small amounts on the solid does not substantially volatilize.

When a water-solids system in a fluidized oil is subjected to a dehydration process, the solids left behind after removing the light oil therefrom by direct contact with hot inert blowing gas are often It can be used for that purpose and therefore constitutes a process product. The method and apparatus of the present invention recovers clean water and substantially dry solids from a variety of sources, whether they be waste solids or solids of inherent value. It can be used for. Thus, for example, the present invention is useful for treating various substances found in aqueous solutions, aqueous dispersions and other water-solid systems associated with water, such as fragmented lime, food, animal feed and waste, cement, spent coal, inorganic salt, sewage, sewage sludge, abattoir effluents and fat leaches, slime, black liquor from the paper industry,
It is useful for recovering water and solids from certain tree bark, sewage, organic streams from kitchen waste disposal equipment, pharmaceutical products and wastes, cannery effluents, chemicals, etc. Thus, depending on the source, the solids recovered from hot blown gas contacting operations can be used as fertilizer, as animal feed or even as food for human consumption, such as dehydrated fat-free food. Furthermore, since they are often flammable,
These may be used to generate the steam necessary to operate the equipment's evaporator, to generate hot inert blowing gas for contact with the concentrated oil-solids slurry or oil-borne solids, or to support auxiliary equipment such as pumps. - Either directly if they are steam-driven pumps or indirectly if they are motor-driven pumps and the steam is used to drive the turbine generator directly - the steam required to operate can be used as a fuel to generate The small amount of heavy oil remaining on the substantially dry solids may also have fuel value. Thus, the process may be at least partially self-sufficient with respect to fuel requirements. Thus, the method and apparatus of the present invention provides a means for the recovery of substantially clean water and valuable solid products from water-solid systems. Furthermore, the invention is characterized by the fact that residual light oil sorbed or otherwise bound to solids is efficiently recovered for reuse.

The material to be treated by the method of the invention is about 1/2
It should contain solid particles generally smaller than 4 inches (6.3 mm). However, as in the case of bone for gelatin production, larger particles may also be tolerated if the voids between the heat transfer surfaces are increased accordingly. Large particles can be crushed or shredded using existing techniques. This is particularly the case for coal.

The oil used for miscibility with the water-solid system prior to the dehydration operation is inert and water-immiscible. Typical relatively non-volatile fluidizing oils or fats include tallow (mutton tallow) and other animal fats and vegetable oils - all of which can be obtained directly from the process operations; petroleum oils, including fuel oils, and Distillates and derivatives; silicone oils, glycerides, high molecular weight fatty acids and miscellaneous effluents from industrial plants that are generally organic. Oils that may confer benefits to the process, i.e., add value to solid products such as waste oil or fuel oil normally found in sewage or industrial waste, or the process itself to minimize the cost factor as described above. It is desirable to use those that can be obtained through the implementation of . The amount of oil is such that the proportion in the system ranges from about 20 parts by weight to more than 20 parts by weight on a non-fat to non-oil basis. This is total oil, i.e. added oil +
Refers to oil recovered from a process for reuse. This amount of oil provides a fluid flowable mixture even in the absence of water. The term "flowable" as used herein is intended to be synonymous with "fluid, flowable", ie, the mixture conforms to the shape of the container to the level it occupies within the container.
It also includes heavy viscous fluids that are pumpable but still suitable for heat transfer purposes.

Light fluidizing oils are not only inert and water-immiscible, but are additionally compatible with direct contact with hot inert blowing gases at temperatures within the range of approximately 21-24°C (70-400°C). It must be sufficiently volatile that it can be evaporated. Generally, about 66~288℃ (150~
550〓), preferably about 149~232℃ (300~450〓)
It is believed that light oils boiling within the range of 100 to 1000 ml are useful for this purpose. Approximately 163~204℃ (325~400
Light oils, such as hydrocarbon oils boiling in the range . This is because this boiling point range allows almost complete removal of oil from the dry solid product. The normally preferred class of gas oils are light hydrocarbon oils. Light hydrocarbon oil is
It can be n-paraffinic, isoparaffinic, aromatic or naphthenic. Examples of suitable light hydrocarbon oils are n-pentene, isopentene, lemonine, hexane, cyclohexane, benzene, isooctane, eicosane,
〓) Petroleum fraction boiling in the range of isohexane,
xylene, octadecane, toluene, n-heptane, cyclopentane and mixtures thereof. Another class of suitable light oils are water-immiscible fatty alcohols. Examples of suitable alcohols are n-hexyl alcohol, n-heptyl alcohol, isoheptyl alcohol, n-octyl alcohol, isooctyl alcohol, n-nonyl alcohol and n-decyl alcohol. Fatty acids such as caproic, caprylic and capric acids and the methyl and ethyl esters of these acids may also be used as light oils. In processing food and animal feed, FDA-approved light oils may be used, such as the isoparaffinic oil series manufactured by Humble Oil and Refining Company under the trade name "Isopar." . Particularly preferred for treating animal feed and food for human consumption are Isopar H and Isopar L. Because their flash point allows safe operation and their boiling point, which is in the range of about 163-204 °C (325-400 °C), allows almost complete removal of oil from dry foods, thereby This is because it passes FDA regulations. Generally, materials that are liquid at operating temperatures, preferably oily, and also relatively volatile and substantially immiscible with water may be used. The use of light oils that confer process benefits, such as waste oils or fuel oils normally found in sewage or industrial waste, or the use of oils derived from the conduct of the process itself to minimize cost factors is often desired. . As with the heavy relatively non-volatile fluidizing oils, the amount of light fluidizing oils ranges from about 2 to 20 parts by weight or more based on the solids portion on a non-fat or non-oil basis. be.

The relatively light oil used to extract the relatively non-volatile residual fluidized oil from the solids dehydrated therein should be inert and miscible with the fixed oil to be extracted. These may or may not be water immiscible. As with light fluidized oil,
They should be sufficiently volatile to be vaporized by direct contact with hot inert blowing gas at temperatures within the range of about 21-204°C (70-400°). The light oils used for extraction generally have the same boiling range as indicated above for light fluidized oils. The light fluidized oils exemplified above are also suitable for extraction of residual fixed oils. The amount of light oil used for extraction of residual fixed oil from solids is
It is not critical and can be determined as appropriate by those skilled in the art. The amount of light oil is a function of the amount of residual oil sorbed onto the solids, which is a function of, for example, the intimacy of the contact between the light oil and the oil-bearing solids, the amount of oil-bearing solids, particle size, shape, and porosity. , and the number of extractions of the oil-borne solids using light oils.

Although the dehydration step of the present invention may be carried out in a single stage or single effect evaporator as known in the art, it is preferred that this step is accomplished in a plurality of sequential thermal evaporation stages. In this case, each successive evaporation stage is at a successively higher temperature, so that the product solids stream becomes increasingly more concentrated due to increasing degree of dehydration. The generated steam of each evaporation stage supplies a substantial portion of the heat requirement of the preceding thermal evaporation stage. A plurality of sequential thermal evaporation stages therefore means at least two stages. The temperature, pressure and concentration in each successive evaporation stage are determined primarily empirically depending on the equipment system and oil used. Typical processing temperatures for the dewatering of fluidized oil/water-solid liquid mixtures are approximately
The temperature ranges from 21 to 121℃ (70 to 250〓), and about 38 to 204℃ (100 to
400〓). Preferred processing temperatures are approximately 32-78°C (90-175〓) in the first stage and approximately 52-177°C (125-175°C) in the second and final stages.
350〓). The above temperature ranges and increments are reasonable in cases where the flow of the mixture to be dehydrated and the heating or drying steam through the evaporator is substantially countercurrent, i.e. in an evaporator in a mode of operation called a backward flow evaporator. be. Temperature also depends on the desired quality of the final product, economics of fuel utilization, cooling water availability, capital investment, etc.

In the above explanation, the term "first stage" refers to the evaporation equipment section in which the fluidized oil/water-solid liquid mixture is placed in the first stage of a plurality of sequential evaporation stages, and the "second stage" ”, “third stage”, etc. On the other hand,
The expression "effect" as in "multiple effects" relates to the flow and action of the heating medium, usually steam, in the evaporation installation. If the flow of fluidized oil/-solid-liquid mixture to be heated and evaporated is countercurrent to the flow of heated steam, the first part of the evaporator
Dan corresponds to the last utility.

Pressure is not critical and is controlled along with temperature to achieve the desired evaporation rate for a given design. Therefore, the first stage pressure is approximately 6.35mm (1/4
Inches of mercury (absolute) to about atmospheric pressure is convenient. In the case of countercurrent flow, the pressure increases in successive stages corresponding to the temperature. It is advantageous to operate the first stage at a pressure below atmospheric pressure and the final stage at a pressure close to atmospheric pressure.

The advantages of using sequential evaporation stages can be seen from the following. For example, in a dual-effect evaporator using an incoming feed at 27°C (80°C), the substance
It may exit the evaporator at 107-121°C (225-250°), with a steam utilization rate of approximately 0.45 Kg (1 lb) to evaporate approximately 0.68-0.79 Kg (1.5-1.75 lb) of water. be. On the other hand, in a typical single effect operation, about 1.5 pounds of steam would be required to achieve the same result with only 1 pound of water evaporating.
If evaporation with three or more effect stages is used, even greater economy in fuel consumption can be realized. It should be noted that the generated steam from each of the thermal evaporation stages after the first stage provides a substantial portion of the heat requirements of the preceding thermal evaporation stage in the case of a countercurrent evaporator. The subtraction or external input heat required is only that required to raise the temperature of the components to the vaporization temperature and provide the heat of vaporization as well as replenish heat losses. The final product from the dewatering step is generally a substantially anhydrous oil-solids slurry containing no more than about 5-10 weight percent water on a non-fat basis.

Although countercurrent evaporators are preferred, any type can be used. Therefore, a countercurrent evaporator,
A co-current evaporator, a counter-current-co-current evaporator, or any combination thereof may be used. Generally preferred equipment is a multiple effect evaporator known in the art, such as a recompression type evaporator such as a Mojonnier, Bufflovac, Rodney-Hunt, thermal or mechanical recompression type. Operationally, the evaporator equipment may be of any type such as forced circulation, flash, falling film circulation, single pass, rotating wipe film, plate, or the like.

Separation of solids and fluidizing oil is conveniently carried out by gravity separation in the case of light fluidizing oils. Whether it is light or heavy fluidized oil,
Separation of the solids may be carried out in a liquid-solid separation means, preferably in a dynamic press such as a centrifuge. When dewatering is carried out on a light fluidized oil, the concentrated oil-solid slurry recovered from a liquid-solid separation means, e.g. a centrifuge, i.e. the solids that have sorbed the residual light oil, is then removed from the residual light oil. Because of this, it is brought into direct contact with hot inert blowing gas. Any residual heavy oil that may be present on the solids is not removed by contact with the blowing gas. On the other hand, when dewatering is carried out in heavy, relatively non-volatile oils, the solids recovered from the liquid-solid separation means, e.g. centrifuges, which have sorbed the residual heavy oil, are removed using light oils. Extracted. Extraction to remove residual heavy oil may advantageously be carried out in a centrifuge. This can be done, for example, in a continuous system where a non-volatile fluidized oil is separated from the solids in the first stage of the centrifuge and the oil-bearing solids are extracted using a relatively light oil in the second stage screen bowl section of the centrifuge. This can be accomplished in a single extraction using a screen bowl centrifuge. The residual light oil sorbed solids recovered from the centrifuge after the extraction stage are then brought into direct contact with hot inert blowing gas for removal of residual light oil therefrom.

In the embodiment of the invention illustrated in FIG. 1, in systems using light fluidized oil in the dewatering stage, the light oil-loaded solids exiting the centrifuge enter a deoiling device operating at substantially atmospheric pressure; These are brought into direct contact with the hot inert blowing gas. The blow gas is the gaseous combustion products from the furnace used to heat the boiler of FIG. 1 which provides steam for the dehydration stage and other uses. The deoiler can be externally heated, if desired, such as by flowing steam through a heating jacket surrounding it. The evaporated light oil and effluent blow gas can be directed from the deoiler and the light oil vapor can be condensed and separated from the effluent gas.

In the embodiment shown in FIG. 2, the solids containing residual non-volatile fluidizing oil are subjected to an extraction operation using light oil in a centrifuge to remove the heavier, relatively non-volatile oil therefrom. The light oil-bearing solids exiting the centrifuge enter a deoiling unit where they are brought into direct contact with hot inert blowing gas. The blowing gas is supplied to a second tank which supplies steam for the heating jacket of the dewatering and deoiling equipment.
Gaseous combustion products from the furnace used to heat the boiler shown. Evaporated light oil and effluent blow gas are led out of the deoiler. Light oil vapor can be suitably condensed and separated from the gas.

In the embodiment of FIG. 3, an inert gas other than the gaseous combustion products is heated in a furnace and brought into direct contact with the light oil-bearing solids in a post-deoiler. Again, vaporized light oil and effluent blow gas are led out of the deoiler.

In the embodiment of FIG. 4, the hot inert blow gas is gaseous combustion products from a furnace not otherwise associated with the equipment system. For example, this furnace is not a furnace used to heat a boiler that provides steam for evaporative dewatering of a fluidized oil/water-solid liquid mixture. The hot gaseous combustion products are contacted directly with light oil-bearing solids in the deoiler. Effluent blow gas and light oil vapor are led out of the deoiler.

DESCRIPTION OF THE EMBODIMENT OF FIG. 1 In the embodiment illustrated in FIG.
into the fluidization tank through. Light fluidized oil enters the fluidized tank 10 through line 14. The fluid mixture in the fluidization tank 10 is stirred by an agitator 16 and removed from the fluidization tank by a post pump 18. Pump 18 delivers the mixture through line 20 to the evaporation region of the first or third effect stage evaporator 22 of the drying evaporator arrangement. In evaporator 22, a portion of the water and light oil is evaporated at a pressure less than atmospheric pressure, which typically may be about 2 to 10 inches of mercury absolute. The temperature of the partially dehydrated and partially deoiled product of the inlet mixture of water-solids in light oil is approximately 21°C depending on the evaporator pressure.
~121℃ (70~250〓, preferably 32~79℃ (90~
175〓) range. This system has a temperature of about 16.7 to
22.2 (30-40〓) higher temperature and enters from the vapor chamber of the next or second stage of the evaporator. Conduit 2
4.Heated by mixed steam-light oil vapor from 4. The heated steam condensate is withdrawn through line 26. Conduit 26 joins conduit 28 at a T-joint. The condensate is conducted through line 28 to an oil-water separator 30. The mixed steam-light oil vapor formed as a result of the partial dewatering of the incoming light oil/water-solid-based liquid mixture is withdrawn from the evaporation chamber of evaporator 22 through line 34 into surface condenser 36 . A partial vacuum is maintained inside the condenser by a vacuum pump 38 connected thereto via line 40.
A mixture of water and light oil vapor entering condenser 36 through line 34 is condensed by cooling water which enters the condenser through line 42 and exits the condenser through line 44.

Inside the oil-water separator 30, the mixture of water and light oil, including the mixture returned from the condenser 126 described below, is separated into light oil and partially clear water containing some light oil. Separated light oil is recovered from water-oil separator 30 through line 48 and directed to light oil storage tank 50.

The partially clarified water is led from the oil-water separator 30 via a line 54 to a condenser 56. Concentrator 56
Inside, partially clear water containing a small amount of light oil is separated into light oil and clear water products. The separated light oil is withdrawn from the condenser 56 through line 58 and finally into the light oil storage tank 5 through line 48.
It leads to 0. Clear water product is recovered from condenser 56 through line 60. If desired, a portion of the produced water can be reused throughout the system. Alternatively, all of the recovered water can be stored in a reservoir for subsequent use in applications where substantially clear water is required.

The partially dehydrated mixture of light oil/water-solids liquid from evaporator 22 is continuously removed through line 62 with the aid of pump 64. The partially dehydrated mixture is forced through line 62 to the evaporation zone of the second stage 66 of the evaporator. In the second stage evaporator, the same process as in the first stage is repeated, except that the pressure is increased. The pressure in successive evaporator stages is somewhat higher than in the preceding stage and approaches near atmospheric pressure in the last stage. The temperature of the further dehydrated product in the second stage evaporator is approximately 38 to 204 °C (100 to 400 °C), preferably approximately 52 to 400 °C, depending on the pressure in the evaporator.
It is in the range of 177℃ (125~350〓). The heating medium is a mixture of steam and light oil vapor at a temperature of about 30-40 degrees above the temperature of the additional dewatered water-solids slurry leaving the second stage evaporator.
The mixed vapor enters through line 68 from the evaporation chamber of the next or third stage evaporator. Condensate of mixed heating steam is withdrawn from the second stage evaporator 66 through line 28 and discharged to an oil-water separator 30. As mentioned above, the mixed steam-light oil vapor formed as a result of additional dewatering is removed from the evaporation chamber of the second stage evaporator 66 through line 24 and transferred to the first stage evaporator 66.
It is used as a heating medium in the stage evaporator 22.

Light oil/water recovered from the second stage evaporator 66 -
Additional dewatered slurry of solids-based liquid is discharged through line 74 by pump 70. The additional dehydrated mixture is conducted through line 74 to the evaporation zone of third stage evaporator 76. The pressure in the third stage is higher than the pressure in the second stage and advantageously is approximately atmospheric pressure.
The temperature of the product of the third stage evaporator 76, a light oil-solids slurry containing about 1% water by weight based on the total slurry, is higher than that of the second stage evaporator 66 and about
38~204℃ (100~400〓) preferably about 66~177℃
(150~350〓). Third stage evaporator 7
The heating medium for No. 6 is steam at a temperature of about 17-28°C (30-50°) above the temperature of the product, the substantially anhydrous oil-solids slurry. This steam is generated in boiler furnace 77 and passed through line 7
8 into the third stage evaporator 76. The heated steam condensate is withdrawn through line 80 and returned to boiler furnace 77. As previously mentioned, the mixed steam-light oil vapor formed as a result of further dewatering of the slurry is removed from the evaporation chamber of the third stage evaporator 76 through line 68 and transferred to the second stage evaporator. 66 as a heating medium.

A substantially anhydrous slurry of light oil-solids is withdrawn from the third stage evaporator 76 and conveyed by pump 82 through line 84 to a continuous centrifuge 86. The light oil is separated from the solids in centrifuge 86 and thence is directed through line 88 to light oil storage tank 50. The recovered light fluidized oil is discharged by pump 90 through line 14 to fluidization tank 10 and recirculated through the system. If the process produces excess oil, it can be recovered from tank 50 and stored for off-system use.

The solids that have sorbed residual light oil are discharged from the continuous centrifuge and enter a movable bottom vessel 94 via conduit 96. The movable bottom of vessel 94 advances the solids to its outlet where they are guided by gravity through conduit 98 into cake deoiling apparatus 100 .
Deoiling apparatus 100 can be externally heated, if desired, by directing steam generated in boiler furnace 77 through line 104 to steam jacket 102. The jacket steam condensate is collected through line 106 and returned to the boiler furnace. The hot gaseous combustion products generated within the furnace of boiler furnace 77 are discharged through furnace chimney 107 . At least a portion of the hot gaseous combustion products is conducted from the furnace chimney 107 through a line 108 connected thereto to the deoiling unit 100 where it is brought into direct contact with the light oil-bearing solids as an inert blow gas. conditions and results in the evaporation of light oils. A fan 109 in line 108 provides pressure to direct the gaseous combustion products through the line. Effluent blow gas and vaporized light oil are discharged from the deoiler through line 110. The pipe 108 is the chimney 10
It will be appreciated that the point of connection to 7 is determined by the desired temperature of the gaseous combustion products, ie inert blowing gas. The higher the desired temperature, the chimney 10
The connection point of conduit 108 to 7 is lower. If maximum blow gas temperature is desired, line 108 can be connected to the furnace of boiler furnace 77 itself.

The solids, free of sorbed light oil, are discharged by gravity from the deoiler 100 through a conduit 114 into a movable bottomed vessel 116. The screw conveyor bottom of vessel 116 directs the solids to its outlet where the solids, substantially anhydrous as well as free of fluidized light oil, are discharged through line 118 to a crusher or pulverizer 119. Ru. By means of the mill 119 the solids are converted into granular form if not powdered and from the mill they flow through line 120 to the rotary selection valve 121 . A selection valve 121 directs these to either line 122 or 123. Line 122 leads to a collection or bagging facility and the solids are recovered for use outside the illustrated system. In the drawing, it is shown as communicating with the conduit 123. The pipe line 123 is the blower 124
and this blower discharges the ground solids through line 125 into the combustion zone of boiler furnace 77.

The exhaust blowing gas and vaporized light oil discharged from the deoiling device 100 are transferred to the surface condenser 1 through a pipe 110.
26. Light oil vapor entering the surface condenser 126 through line 110 is condensed by cooling water which enters the condenser through line 128 and exits therefrom through line 130. Some incidental water resulting from the condensation of the condensed light oil and water carried away from the solid product and water entrained in the inert gas, in this case the flue gas, flows from the condenser through line 132 to the oil. - discharged into the water separator 30; The cooled exhaust gas is discharged to the atmosphere through line 134. Since the effluent blow gas is freely discharged from the condenser to the atmosphere, the deoiler 10
The pressure within 0 is substantially atmospheric pressure. The deoiling step is therefore carried out at substantially atmospheric pressure. The effluent blow gas and vaporized light oil from the deoiler 100 are shown in FIG. 1 as being directed to a condenser 126 where the oil vapor is condensed and separated from the gas; - It will be appreciated that the energy of the light oil vapor mixture can be recovered by supplying heat to the first stage evaporator 22 or the second stage evaporator 66 or virtually any evaporation stage in the system. However, the shell side of the third stage evaporator 76 is excluded. This is because the oil contained therein may contaminate the condensate water returned to the boiler furnace 77 through line 80 and the temperature of the mixture may not be high enough to provide the heat transfer requirements. Alternatively, the effluent blow gas and vaporized light oil can be used as fluidized oil/oil by blowing into the fluidization tank 10 or at any other location within the system where recovery of that energy can benefit the process. It can be used to preheat water-solid liquids.

The foregoing discussion of FIG. 1 applies if the water-solid system does not initially contain heavy, relatively non-volatile oil. If the heavy, relatively non-volatile oil is originally associated with the water-solid system, the heavy oil will be extracted by the light fluidizing oil during the press operation. 1st
In the embodiment shown, the entire oil from the press operation is recycled as fluidizing oil. Therefore, if heavy oil is present, an equilibrium condition is already achieved in which the heavy oil is extracted from the water-solid system by the fluidizing oil in the same proportion as it is replaced by the recycled oil. The result of the subtraction is a substantially dry solid product having substantially the same heavy oil content as the initial feed on a water-free basis.

Explanation of the Example of Figure 2 Figure 2 shows that a mixture of a relatively non-volatile fluidizing oil and a water-solid liquid is dehydrated by thermal evaporation, and then the substantially anhydrous solid is converted to a non-volatile liquid. An embodiment of the invention is shown in which the main portion of the oil is separated. The substantially anhydrous solids sorb the remaining relatively fixed oil, the latter being removed by an extraction operation using a relatively volatile light oil. The solids containing residual light oil are then brought into direct contact with the gaseous combustion products from the furnace in a deoiler.

In an embodiment using the equipment shown in FIG. 2, a stream of water-solids liquid in the form of a solution or dispersion enters fluidization tank 138 through line 140. Non-volatile fluidizing oil enters fluidizing tank 138 through line 142. Fluidization tank 1
The fluid mixture within 38 is agitated by an agitator 144 and removed from the fluidization tank by a post pump 146. Pump 146 sends the mixture through line 148 to mill 150 where the solid particles are ground to a maximum size of about 1/4 inch. A portion of the effluent from the grinder, such as difficult-to-grind materials, is returned to fluidization tank 138 through line 152, while the remainder of the effluent is returned to fluidization tank 138 through line 154.
to the supply tank 156. The fluid mixture in the supply tank 156 is agitated by an agitator 158 and removed from the supply tank by a post pump 160. Pump 160 pumps the fluid mixture through line 162. Conduit 162
opens into conduit 164 at a T-joint. The fluid mixture is directed through line 164 to the first stage (or fourth effect stage) evaporator 166 of the drying evaporator arrangement. In the evaporator 166, typically about 51 to 254
Volatizes at subatmospheric pressures of 2 to 10 mm (2 to 10 inches) of mercury absolute. The temperature of the partially dehydrated product of the incoming non-volatile fluidized oil/water-solid liquid mixture is approximately 21-121°C (70-121°C) depending on the pressure in the evaporator.
250〓), preferably in the range of about 32-79°C (90-175〓). The mixture is passed through line 1 at a temperature of approximately 17-22°C (30-40〓) above the temperature of the partially dehydrated mixture.
It is heated by steam from 68. The heated steam condensate is collected through line 170 into hot liquid sump 172 . Water vapor formed as a result of partial dewatering is removed from the vapor chamber of evaporator 166 through line 174 to atmospheric leg condenser 176 . Condenser 17
A partial vacuum is maintained within 6 by a vacuum pump 178 connected thereto via a vacuum line 180.

Water vapor entering condenser 176 through line 174 is mixed with cooling water entering the condenser through line 182 and condensed, and the resulting hot water stream is discharged through line 184 to hot water sump 186. From the hot water sump 186, produced water is withdrawn through a water leg discharge line 188. If desired, a portion of the produced water can be reused throughout the system. Alternatively, all of the recovered water may be stored in a reservoir for subsequent use in applications requiring substantially clean water.

The partially dehydrated mixture from evaporator 166 is transferred to pump 1
90 is continuously removed through line 164. Conduit 164 is connected to conduit 1 at the T-joint.
92. A portion of the mixture discharged from evaporator 166 passes through line 164 to evaporator 166.
and a portion flows into line 192. A pump 196 pumps this partially dehydrated mixture through line 192 and finally line 194 to a second
to stage evaporator 198. In the second stage evaporator, the same process as in the first stage is repeated, except that the pressure is generally increased. The pressure in each successive evaporator stage is usually somewhat higher than in the preceding stage;
At the final stage, the pressure approaches almost atmospheric pressure. The temperature of the additional dehydration product in the second stage evaporator is approximately 38-204°C (100-400〓), preferably approximately 93-177°C (200-350〓), depending on the pressure in the evaporator. in range. The heating medium is steam at a temperature of about 17-22°C (30-40°) above the temperature of the additional dewatered slurry exiting the second stage evaporator. The heating steam is
It enters through line 200 from the evaporation chamber of the stage evaporator. The heated steam condensate is discharged through line 204 to hot liquid reservoir 172 .

Additional dewatered slurry recovered from second stage evaporator 198 is removed through line 194 by pump 206 . A portion of this slurry is recycled through line 194 back to evaporator 198 and the remainder flows to line 208. Pump 212 pumps this slurry through line 208 and ultimately into line 21.
0 to the third stage evaporator 214. Although the pressure in the third stage is generally higher than in the second stage, it is advantageous for it to be somewhat below atmospheric pressure. Third
The temperature of the further dehydrated mixture leaving the stage evaporator is about 38-204°C (100-400°C), preferably about
It ranges from 200 to 350°C and is usually somewhat higher than the temperature of the mixture from the second stage evaporator 198. The heating medium is approximately 17 cm below the temperature of the product.
The steam is at a temperature of ~28°C (30-50°) higher and enters through line 216 from the next stage 4 evaporator. The heated steam condensate is withdrawn through line 218 and discharged into hot liquid sump 172 .

Further dewatered slurry recovered from third stage evaporator 214 is discharged through line 210 by pump 220 . As before, a portion of the slurry is returned and the remainder flows into line 222. A pump 226 pumps the slurry through lines 222 and 224 to a fourth stage evaporator 228 . The pressure in the fourth stage is usually higher than the pressure in the third stage, advantageously about atmospheric pressure. The temperature of the product of the fourth stage evaporator 228, an oil-solids slurry containing about 1% water by weight based on the total slurry, is generally higher than the temperature of the product of the third stage evaporator 214, from about 38 to 204
℃ (100-400〓), preferably about 93-177℃ (200
~350〓). The heating medium is steam at a temperature of about 17-28°C (30-50°) above the product temperature. This steam is boiler furnace 2
30 and is conducted through line 232 to fourth stage evaporator 228 . The heated steam condensate is returned to the boiler furnace 230 through line 234.

The substantially anhydrous oil-solids slurry withdrawn from the fourth stage evaporator 228 is discharged through line 224 by pump 236. A portion of the slurry is again recycled back to the evaporator 228 through line 224 and the remainder flows into line 238. A pump 240 pumps the slurry through line 238 to a continuous centrifuge 244 . The centrifuge 244 includes a first section of imperforate bowl and a second section of screen bowl.
compartments are equipped. Most of the relatively non-volatile fluidizing oil is separated from the solids in the imperforate bowl first section of centrifuge 244 and from there into line 24.
6 to a recirculating fluidized oil tank 248. The recovered fluidized oil is discharged by pump 250 through line 142 to fluidized tank 138;
Recirculated through the equipment system. If the process produces surplus fluidized oil, it is recovered from tank 248 and stored for off-system use.

The solids sorbing the residual fluidized oil are transferred to centrifuge 2.
44 from the first section of the imperforate bowl to the second section of the screened bowl. A relatively volatile, low viscosity light oil is introduced through line 252 into the screen bowl second section of centrifuge 244 where residual fluidized oil is brought into intimate contact with the sorbed solids. . The relatively light oil extracts the fluidized oil from the solids in the screen bowl second section of centrifuge 244 and the mixture of light oil and extracted fluidized oil is discharged through line 254 to tank 256.

The solids, which now have sorbed the remaining relatively light oil, are discharged from the screen bowl compartment of the centrifuge 244 and transferred to the movable bottom vessel 258.
to go into. The movable bottom of vessel 258 advances the solids to its outlet where they fall by gravity through conduit 260 into cake deoiler 262 . The deoiling device 262 can be installed in the boiler furnace 2, if desired.
External heating may be provided by steam generated at 30 and passed through line 266 to steam jacket 264. Jacket steam condensate is removed through line 268 and returned to boiler furnace 230. The high temperature gaseous combustion products generated in the furnace of the boiler furnace 230 are transferred to the furnace chimney 27.
Emitted through 0. At least a portion of the hot gaseous combustion products are introduced from the furnace chimney 270 into the deoiler 262 through a line 272 connected thereto and which may incorporate a precipitator of any suitable design, where the waste is removed. As an active blowing gas, it is brought into direct contact with the light oil-bearing solids and results in vaporization of the light oil. Fan 274 within conduit 272
provides pressure for directing gaseous combustion products through line 272. Emerging blow gas and vaporized light oil exit the deoiler through line 276. It will be appreciated that the point at which line 272 connects to furnace chimney 270 is determined by the desired temperature of the gaseous combustion products or inert blowing gas. The higher the desired temperature, the lower the connection point. If maximum blow gas temperature is desired, line 2
72 may be connected to the furnace of boiler furnace 230 itself.

The solids from which the sorbed light oil has been removed are discharged by gravity from the deoiling device 262 into a container 278 with a movable bottom. The screw conveyor bottom of vessel 278 directs the solids to its outlet where the solids, not only substantially dry, but also free of fluidizing oil as well as light oils, are discharged through line 280.

Outflow blown gas + vaporized light oil discharged from the deoiling device 262 is transferred to the surface condenser 28 via a pipe 276.
Guided within 2. Light oil vapor enters the condenser through line 284 and is condensed by cooling water exiting therefrom through line 286. Condensed gas oil and some unavoidable water are discharged from the condenser through line 288 into tank 290 . Tank 290 is divided into a light oil-water tank and a light oil surge tank. The cooled effluent blow gas is discharged from the condenser to the atmosphere through line 292. The pressure within the deoiling device 262 is substantially atmospheric because the effluent blow gas is freely discharged from the condenser to the atmosphere. The deoiling step is therefore carried out at substantially atmospheric pressure. In FIG. 2, the outflow blown gas + vaporized light oil from the deoiling device 262 is
Although shown as being directed to a condenser 282 where the oil vapor is condensed and separated from the gas, the energy of the blown gas-light oil vapor mixture provides heat to any evaporation stage in the system. can be recovered by However, the shell side of the fourth stage evaporator 228 is excluded. This is because the oil contained therein may contaminate the condensate water returned to the boiler furnace 230 through line 234 and the temperature of the mixture may not be high enough to provide the heat transfer requirements. Alternatively, the effluent mixture may be injected into the fluidization tank 138 to preheat the water-solids liquid/fluidized oil mixture or anywhere else in the system where heat recovery would provide a process benefit. can be used.

The mixture of relatively light oil and extracted fluidized oil in tank 256 is pumped to line 29 by pump 296.
8 through the evaporator tube bundle 30 of the second stage evaporator 198
released at 0. Flow rate through line 298 is controlled by valve 302. The extracted fluidized oil portion is combined with a partially dehydrated slurry and removed from the second stage evaporator 198 through line 194, while the light oil is vaporized and removed with steam from the vapor chamber of the second stage evaporator 198 through line 168. It is guided and serves as a heating medium in the first stage evaporator 166. Those skilled in the art will appreciate that a separate evaporator tube bundle 300 need not be used and the mixture can be discharged from tank 256 to any evaporation stage in the system.

Line 304 (below the second stage evaporator) is connected by a tee to line 194 at one end and to line 298 at the other end. The flow rate of light oil + extracted fluidized oil through line 298 as well as the pressure in line 298 is such that a portion of the slurry passing through line 194 passes through line 304 to line 298 and finally to evaporator tube bundle 300. The flow is diverted and the slurry is controlled by valve 302 for additional evaporation.

From the top of the evaporation zone of the third stage evaporator 214, a conduit 306 extends through which the non-condensable material +
An adjoint condensable substance is introduced. Access to line 306 is controlled by valve 308. A line 310 controlled by a valve 312 leads from the top of the evaporation zone of the second stage evaporator 198 to line 306 via a T-joint. Similarly, line 3 controlled by valve 316
14 connects the top of evaporation zone 300 to line 306 and is controlled by valve 320
connects the top of the evaporation zone of the first stage evaporator 166 to the pipe 3
Connect to 06. A partial vacuum is maintained in line 306 by an ejector 324 which is supplied with steam through line 326. Species 308, 312, 316
and 320, a desired level of vacuum can be maintained in each of the third, second and first stage evaporators.

Steam and non-condensable and condensable materials from ejector 324 are introduced into seal tank 330 through line 328. Non-condensable substances and accompanying condensable substances are transferred to a sealed tank 330 via line 332.
to a surface condenser 334. Surface condenser 334 is cooled by cooling water entering it through line 336 and exiting it through line 338. Non-condensable materials exit surface condenser 334 through line 340. Entrained condensables are returned from surface condenser 334 to seal tank 330 through line 344. Condensable material, consisting essentially of water and relatively light oil, is conducted from sealed tank 330 to tank 290 by line 346. As mentioned above, the tank 290 is divided into a light oil-water tank and a light oil surge tank. Condensate, consisting essentially of water and light oil, is pumped from hot liquid sump 172 to tank 290 through line 350 by pump 348.

Inside tank 290, the mixture of water and relatively light oil is separated into substantially pure light oil and partially clear water containing a small amount of light oil. The former goes into the light oil surge tank and the latter stays in the light oil-water tank. Excess light oil is pumped through line 354 by pump 352 to a storage tank. The light oil required in the process for extracting fluidized oil from solids is conveyed by pump 356 from the light oil surge tank to continuous centrifuge 244 through line 252 .

Partially transparent water containing a small amount of light oil is pumped using pump 358.
from the light oil-water tank of tank 290 to condenser 360 through line 362. Clear water is removed from condenser 360 through line 364 and collected in a storage tank. Concentrator 360
The light oil separated from the water at is removed from the condenser through line 366 and further through lines 368 and 370. The latter two conduits are connected to conduit 366 at a T-joint. Line 366 conducts the light oil back to tank 290 where it enters a light oil surge tank and is ultimately sent to a storage tank or continuously centrifuged for the purpose of extracting the fluidized oil from the solids. will be returned to.

DESCRIPTION OF THE MODIFICATION FIG. 3 shows a portion of the equipment used in a modification of the FIG. 1 or FIG. The inert gas is heated in a heating device that is otherwise unrelated to the equipment of Figure 2. The equipment shown in Figure 3 is fundamentally different from the equipment shown in Figures 1 and 2 in that the hot inert blowing gas is an inert gas such as nitrogen or carbon dioxide rather than gaseous combustion products. different. Although FIG. 3 is shown as a modification of the equipment of FIG. 1, it should be understood that similar modifications could easily be applied to the equipment of FIG. Also, although FIG. 3 illustrates the use of the boiler furnace 77 of FIG. 1 as the inert gas heating means, the inert gas may be heated in a separate heating device that is not otherwise related to the equipment of FIG. It's okay.

In FIG. 3, light oil-solids enter cake deoiler 100 via conduit 98. Oil removal device 10
0 is generated in boiler furnace 77 and passed through line 104 to steam jacket 10.
It can be externally heated by steam introduced into 2. Condensate from the jacket steam is removed through line 106 and returned to the boiler furnace. The inert gas in the heating coil 374 is transferred to the boiler furnace 7
It is heated inside the furnace chimney 107 of No. 7. Heating coil 374 is connected to conduit 108 at one end. Line 108 conducts the hot inert blow gas to a deoiling unit where the blow gas is brought into direct contact with the light oil bearing solids and results in vaporization of the light oil. The solids, free of sorbed light oils, are discharged from the deoiler through line 114. A fan 109 in line 108 provides pressure to force hot inert blow gas through line 108. The effluent inert blow gas + vaporized light oil exits the deoiler through line 110. Furnace chimney 10
Those skilled in the art will appreciate that the position of heating coil 374 within 7 is determined by the desired temperature of the inert blowing gas. The higher the desired temperature, the more the furnace chimney 1
The position of the heating coil 374 in 07 is lowered. If maximum inert blow gas temperature is desired, heating coil 374 may be installed inside the furnace of boiler furnace 77.

Outflow blown gas flowing out from the deoiling device 100 +
The vaporized light oil is transferred to a surface condenser 126 via a pipe 110.
will be introduced in Surface condenser 1 through line 110
Light oil vapor entering 26 is routed through lines 128 and 130.
It is condensed by cooling water that circulates through the condenser. The condensed light oil is passed from the condenser to pipe 13.
released through 2. The cooled effluent inert gas is discharged from condenser 126 through line 376. Pipe line 376 is connected to the other end of heating coil 374. The inert blowing gas is thus circulated.

FIG. 4 shows a modification of the equipment of FIGS. 1 or 2, in which the hot inert blowing gas is
Gaseous combustion products from a furnace not otherwise related to the equipment of FIG. Figure 4 shows
Although this is an example of modification of the equipment shown in FIG. 1, it can also be applied to the equipment shown in FIG.

In FIG. 4, the light oil-bearing solids enter cake deoiler 100 via conduit 98. Oil removal device 10
0 can be externally heated, if desired, by steam generated in boiler furnace 77 and flowing into steam jacket 102 through line 104. The condensed water from the jacket steam is pipe 1.
06 and returned to the boiler furnace 77. Steam for heating the evaporator stages of the system is also generated in boiler furnace 77 and led through line 78 to third stage evaporator 76. The heated steam condensate is withdrawn through line 80 and returned to the boiler furnace.

Hot gaseous combustion products are generated in furnace 380, which may be an industrial inert gas generator of known design in nature. At least a portion of this hot gaseous combustion product is introduced into the deoiling apparatus 100 from the furnace chimney 382 via a line 384 connected thereto, where it is carried as an inert blow gas with light oil. It is brought into direct contact with the solid and results in light vaporization. The solids, free of sorbed light oils, are discharged from the deoiler 100 through conduit 114. The fan 386 in the conduit 384 is connected to the conduit 3
84 to provide pressure for directing gaseous combustion products. The effluent blow gas plus vaporized light oil exits the deoiler through line 110. As discussed above, the point of connection of line 384 to furnace chimney 382 is determined by the desired temperature of the gaseous combustion products.
That is, the higher the desired temperature of the gaseous combustion products, the lower the connection point of line 384 to chimney 382.
To obtain maximum blow gas temperature, line 38
4 is connected directly to the furnace.

The effluent blow gas + vaporized light oil from the deoiler 100 is shown in FIG. 4 as being directed to a condenser 126 where the oil vapor is condensed and separated from the effluent gas. The energy of the mixed gas + light oil vapor mixture is transferred to the first stage evaporator 22,
It can be recovered by supplying heat to the second stage evaporator 66 or to any evaporation stage in the system. However, the shell side of the third stage evaporator 76 is excluded. This is because the oil entrained therein contaminates the condensate water returned to the boiler furnace 77 through line 80 and the temperature of the mixture may not be high enough to provide the heat transfer requirements. Alternatively, the effluent blow gas + vaporized light oil can be blown into the fluidization tank 10 to preheat the mixture therein or at any point in the system where recovery of its energy could provide a process benefit. Can be used at any location.

Effects of the Invention The present invention provides a method and apparatus for removing light oil from solids. The present invention particularly relates to the residual light oil from the solids obtained in a process in which a water-solid liquid is dehydrated in a light fluidized oil medium and the majority of the light fluidized oil is separated from the substantially anhydrous solids. It can be applied to the removal of The present invention also provides that a water-solid liquid is dehydrated in a heavy, relatively non-volatile fluidizing oil, and that the majority of the heavy oil is separated from the substantially dry solids and that the residual oil is further separated from the light solids. It is also useful for removing residual light oils from solids obtained in processes where oil is removed from the solids by extraction operations. The process is characterized by recovering clean water from a water-solid liquid that is dehydrated in a fluidized oil medium and recovering residual light oil from the solids after the dewatering. The light oil-bearing solids are brought into direct contact with a hot inert blowing gas, the latter removing residual light oil by thermal evaporation. Additionally, the present invention is extremely beneficial in allowing the recovery of solids that are not only dewatered, but also deoiled beyond levels normally achievable by mechanical means alone.

[Brief explanation of the drawing]

Figure 1 shows that a relatively volatile water-immiscible light fluidized oil/water-solid liquid mixture is dehydrated by a thermal evaporation operation, the light fluidized oil is separated from the substantially anhydrous solids, and the remaining light fluidized oil is separated from the substantially anhydrous solids. Figure 1 provides an overview of the installation of one embodiment of the present invention in which anhydrous oil-containing solids are contacted directly with an inert blowing gas, a gaseous combustion product from a furnace, in a deoiling unit to remove residual light oil; FIG. FIG. 2 is a flowchart outlining a facility that performs a similar process using a relatively non-volatile fluidizing oil. FIG. 3 shows a partially modified example of the equipment shown in FIG. 1 or 2. FIG. 4 similarly shows another modified example. 12: Water-solid liquid supply line, 10: Fluidization tank, 16: Stirrer, 14: Light fluidized oil supply line, 22, 66, 76: Evaporator, 77: Boiler furnace, 86: Centrifuge , 100: Deoiling device, 50: Light oil storage tank, 140: Water-solid liquid supply line, 138: Fluidization tank, 142: Non-volatile oil supply line, 166, 198, 214, 228: Evaporator , 244: Centrifuge, 230: Boiler furnace, 2
52: Light oil supply pipe line, 262: Deoiling device, 24
8: Non-volatile oil storage tank.

Claims (1)

[Claims] 1 (1) Water-solid liquid and about 66 to 288°C (150 to 550°C)
〓) by mixing with a low viscosity, relatively non-volatile, water-immiscible light fluidizing oil boiling within the range of
(2) dehydrating the resulting oil-containing mixture by thermal evaporation, thereby removing substantially all of the water and fluidizing oil; (3) condensing the water and light oil vapor mixture, and (4) producing condensation. separating the liquid into a clear water portion and a light oil portion;
(5) separating at least a portion of the relatively volatile, water-immiscible light fluidizing oil from the substantially anhydrous co-body-oil slurry; and (6) the resulting residual light fluidizing oil. bringing the supported solid into direct contact with a hot inert blowing gas selected from the group consisting of combustion product gases, nitrogen and carbon dioxide, thereby removing light oil from said solid by thermal evaporation; , (7) condensing and separating the light oil vapor in an inert blowing gas containing the light oil vapor flowing out; and (8)
The separated light oil from steps (4), (5) and (7) is washed with fresh water.
A water-solid liquid treatment method comprising the step of mixing with a solid liquid and recycling and reusing it in a process as a fluidizing oil. 2. The method of claim 1, wherein the blowing gas is selected from the group consisting of nitrogen and carbon dioxide. 3. The method of claim 2, wherein the effluent blow gas is reheated and recycled as hot inert blow gas after removing light oil vapor therefrom. 4. The method of claim 1, wherein the injected gas is a gaseous combustion product from an external combustion device. 5. The method of claim 1, wherein the thermal evaporation step (2) is carried out at a temperature within the range of about 21-204°C (70-400°). 6 Solids carrying residual light fluidized oil are approximately 21~
The method of claim 1, wherein the method is brought into direct contact with an inert blowing gas at a temperature within the range of 204°C (70-400°C). 7. Claim 1 in which at least part of the oil-free solids from stage (6) is used as at least part of the fuel for supplying heat for thermal evaporation stage (2)
The method described in section. 8 Light fluidized oil is approximately 163-204℃ (325-400〓)
The method according to claim 1, wherein the hydrocarbon oil boils within the range of . 9 Light hydrocarbon fluidizing oils such as Isopar H and
9. The method of claim 8, wherein the method is selected from Isopar L. 10 (1) mixing a water-solid liquid with a relatively nonvolatile oil to obtain a mixture that retains fluidity and flowability even after water removal; and (2) applying heat to the resulting oil-containing mixture. dehydrating by evaporation to produce water vapor and a substantially anhydrous solid-oil slurry;
(3) condensing water vapor; (4) separating a majority of the relatively non-volatile oil from the solid-oil slurry; and (5) removing a relatively non-volatile oil from the resulting oil-bearing solids. (6) using a light oil of low viscosity to substantially remove it by an extraction process; and (6) injecting the resulting light oil-bearing solids with a high temperature inert blowing selected from the group consisting of a combustion product gas, nitrogen and carbon dioxide. (7) bringing the solid into direct contact with a gas, thereby removing light oil from the solid by thermal evaporation;
(8) a step (7) of condensing and separating the light oil vapor in an inert blowing gas containing the light oil vapor flowing out;
A water-solid liquid treatment method comprising the step of adding the separated light oil from the light oil to the light oil used in the extraction step (5) and recycling and reusing it in the process. 11. The method of claim 10, wherein the blowing gas is selected from the group consisting of nitrogen and carbon dioxide. 12. The method of claim 11, wherein the effluent blow gas, after removing light oil vapor therefrom, is reheated and recycled as hot inert blow gas. 13. The method of claim 10, wherein the injected gas is a gaseous combustion product from an external combustion device. 14 Thermal evaporation stage 2 is approximately 21~204℃ (70~400〓)
11. The method of claim 10, carried out at a temperature within the range of . 15 Light oil-supported solids are approximately 21 to 204℃ (70 to 400℃)
11. The method of claim 10, wherein the method is brought into direct contact with an inert blowing gas at a temperature within the range of . 16. Claim 10, wherein at least part of the oil-free solids from stage (6) is used as at least part of the fuel for supplying heat for thermal evaporation stage (2). the method of. 17. Claim 1, wherein the relatively low viscosity light oil used in extraction step 5 is a hydrocarbon oil boiling in the range of about 163-204°C (325-400°C).
The method described in item 0. 18. The method of claim 17, wherein the light oil is selected from Isopar H and Isopar L. 19 (1) a tank adapted to receive a stream of water-solids liquid and provided with an agitator; (2) a light fluidizing oil sump; and (3) a light fluidizing oil sump from the light fluidizing oil sump to the tank. (4) an evaporator; (5) a conduit extending from the tank to the evaporator; (6) a first condenser; and (7) a conduit extending from the evaporator to the first condenser. (8) oil-water separation means; (9) a conduit extending from the first condenser to the oil-water separation means; and (10) separately recovering light oil and clean water from the oil-water separation means. (11) a conduit extending from the recovery means to the light fluidized oil sump; (12) liquid-solid separation means; and (13) a conduit extending from the evaporator to the liquid-solid separation means. (14) a deoiling means; (15) a conduit extending from the liquid-solid separation means to the deoiling means; (16) a conduit extending from the liquid-solid separation means to the light fluidized oil sump;
7) a boiler furnace comprising a boiler zone and a heating zone; (18) a conduit extending from the boiler zone of the boiler furnace to the evaporator; and (19) a conduit extending from the heating zone of the boiler furnace to the deoiling means. (20) a second condenser; (21) a conduit extending from the deoiling means to the second condenser; and (22) connecting the second condenser and the light fluidized oil sump. A water-solid liquid treatment apparatus comprising means. 20. Claim 1, wherein the conduit extending from the heating zone of the boiler furnace to the deoiling means is equipped with a fan to facilitate the transfer of hot inert blowing gas.
The method described in Section 9. 21 (1) a tank adapted to receive a stream of water-solids liquid and provided with an agitator; (2) a light fluidizing oil sump; and (3) a light fluidizing oil sump from the light fluidizing oil sump to the tank. (4) an evaporator; (5) a conduit extending from the tank to the evaporator; (6) a first condenser; and (7) a conduit extending from the evaporator to the first condenser. (8) oil-water separation means; (9) a conduit extending from the first condenser to the oil-water separation means; and (10) separately recovering light oil and clean water from the oil-water separation means. (11) a conduit extending from the recovery means to the light fluidized oil sump; (12) liquid-solid separation means; and (13) a conduit extending from the evaporator to the liquid-solid separation means. (14) a deoiling means; (15) a conduit extending from the liquid-solid separation means to the deoiling means; (16) a conduit extending from the liquid-solid separation means to the light fluidized oil sump;
7) a boiler furnace comprising a boiler zone and a heating zone; (18) a conduit extending from the boiler zone of the boiler furnace to the evaporator; and (19) a heat transfer disposed within the heating zone of the boiler furnace. (20) a conduit extending from a first end of the heat transfer means to the deoiling means; (21) a second condenser; and (22) a conduit extending from the deoiling means to the second condenser. (23) means for connecting said second condenser and said light fluidized oil sump; and (24) a conduit extending from said second condenser to a second end of said heat transfer means. -Solid liquid processing equipment. 22. The apparatus of claim 21, wherein the conduit extending from the first end of the heat transfer device to the deoiling means is equipped with a fan to facilitate transfer of hot inert gas through the conduit. 23 (1) a tank adapted to receive a stream of water-solids liquid and equipped with an agitator; (2) a light fluidizing oil sump; and (3) a light fluidizing oil sump from the light fluidizing oil sump to the tank. (4) an evaporator; (5) a conduit extending from the tank to the evaporator; (6) a first condenser; and (7) a conduit extending from the evaporator to the first condenser. (8) oil-water separation means; (9) a conduit extending from the first condenser to the oil-water separation means; and (10) separately recovering light oil and clean water from the oil-water separation means. (11) a conduit extending from said recovery means to a light fluidized oil sump; (12) liquid-solid separation means; and (13) a conduit extending from said evaporator to said liquid-solid separation means. (14) a deoiling means; (15) a conduit extending from the liquid-solid separation means to the deoiling means; (16) a conduit extending from the liquid-solid separation means to a light fluidized oil sump;
a boiler furnace having a boiler zone for steam generation; (18) a conduit extending from the boiler zone of the boiler furnace to the evaporator; and (19) heating for combustion gas generation, separate from the boiler furnace. an additional combustion device having a zone; (20) a conduit extending from the heating zone of the combustion device to the deoiling means; (21) a second condenser; and (22) a conduit extending from the deoiling means to the second condenser. and (23) a conduit connecting the second condenser and a light oil fluidization oil sump. 24. The apparatus of claim 23, wherein the conduit extending from the heating zone of the combustion device to the deoiling means is equipped with a fan to facilitate the transfer of hot inert gas through the conduit. 25 (1) a tank suitable for containing a stream of water-solid liquid and equipped with mixing means; (2) a relatively non-volatile fluidizing oil sump; and (3) a relatively non-volatile oil sump. (4) an evaporator; (5) a conduit extending from the tank to the evaporator;
a first condenser; (7) a conduit extending from the evaporator to the first condenser; (8) means for recovering steam condensate from the first condenser as a clean water product; (10) a conduit extending from the evaporator to the liquid-solid separation means; (11) a light oil sump; (12) a conduit extending from the light oil sump to the liquid-solid separation means; ) conduit means extending from said liquid-solid separation means to said sump; (14) conduit means extending from said liquid-solid separation means to an evaporation zone of said evaporator; (15) deoiling means; ) a conduit extending from said liquid-solid separation means to a deoiling means; (17) a boiler bank comprising a boiler region and a heating region for generating steam and combustion product gas; and (18) a boiler zone of a boiler furnace. (19) a conduit extending from the heating zone of the boiler furnace to the deoiling means; (20)
A water-solids treatment device comprising: a second condenser; (21) a conduit extending from the deoiling means to the second condenser; and (22) means for connecting the second condenser and a light oil sump. . 26. The apparatus of claim 25, wherein the conduit extending from the heating zone of the boiler furnace to the deoiling means is equipped with a fan to facilitate the transfer of hot inert gas through the conduit.