JPS58109587A - Improved liquefaction of solid carbonaceous material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved method for converting solid carbonaceous materials such as coal. More particularly, the present invention relates to an improved method for liquefying solid carbonaceous materials such as coal.

As is well known, proven oil and gas reserves are decreasing worldwide and the demand for alternative energy sources has become increasingly evident. One alternative energy source of this kind is, of course, coal. Because,
This is because coal is an abundant fossil fuel in many countries throughout the world.

However, for coal to become commonly metered by end consumers, it needs to be converted into a form that can be used in areas where liquid or gaseous fuels are normally required. There will be.

For this purpose, several methods of liquefying and/or gasifying coal have been proposed in the past. Among these methods, the method of liquefying coal seems to be more desirable. This is because a wider range of products is produced and these products can be more easily transported and stored.

Among these several liquefaction methods proposed in the past, a method in which coal is liquefied in the presence of a solvent, especially a diluent, especially a water donor solvent or diluent, and in the presence of a hydrogen-containing gas is more popular. Seems like it would give a big advantage. In these processes, liquefaction takes place at high temperatures and pressures, and it is inevitable that hydrocarbon gases will be produced as by-products. However, in most cases these and other liquefaction methods result in usually solid residual products containing relatively large amounts of carbon, which can be further processed if economical waste-free methods are sought. It cannot be disposed of without any damage. Several methods have been proposed to avoid this drawback. For example, a normally solid residual product is reduced to the point where its carbon content is sufficiently low that its disposal does not significantly affect the economics of the process. The product can be further subjected to liquefaction K in a separate stage. However, gradual liquefaction requires K
The additional equipment required and the energy and other utilities required significantly increase both investment and operating costs. In the past, it has also been proposed to circulate all or part of the normally solid residual product to a single or multiple liquefaction stages. However, when doing this, most of the recycled material is either non-reactive (ash) or difficult to convert (fusinite). These materials amount to up to 60% of the 'OMfR materials, and recycling these materials increases costs and reduces thermal efficiency. Previously, it has been proposed to simply combust these normally solid residual products directly, or to gasify the normally solid residual products to produce gaseous products, which are then combusted as fuel. . however,
Operating in this manner reduces the yield of normally liquid product, thus reducing thermal efficiency and increasing both capital and operating costs for much the same reasons as discussed above with respect to staged or additive liquefaction. Finally 1
It has also previously been proposed to separate the non-reactive Fujinit portion of the residual product from the reactive portion by extraction. Generally, however, these operations rely on the use of relatively expensive solvents (eg toluene), which must then be separated from the extract, generally by vaporization. This type of operation also proves to be expensive, mainly due to the high energy requirements for separating the solvent.

In view of the above, there is a need for a liquefaction process that can be operated with increased thermal efficiency in a manner that requires fewer liquefaction steps and that results in a normally solid residual product that has a relatively low carbon content and can be disposed of. seems to be easily realized.

More specifically, there is likely to be a need for a liquefaction process that efficiently recovers by extraction a significant portion of the carbon contained in the normally solid residual product.

It has now been found that these and other drawbacks of conventional methods may be reduced by the method of the present invention and the improved liquefaction process provided thereby. It is therefore an object of the present invention to provide an improved liquefaction process which increases the yield of a liquid product at high temperatures and pressures without the objective of liquefaction and yet with an inert fusinite of the normally solid residual product. The residual product, which is enlarged without recycling the portions and is usually isomeric, can preferably be disposed of directly after the extraction operation, with less impact on the economics and thermal efficiency of the process. These and other objects and advantages will become apparent from the following description and accompanying drawings.

In accordance with the present invention, these and other objects and advantages are achieved by liquefying a solid carbonaceous material, such as coal, in the presence of a hydrogen donor solvent at high temperatures and pressures, and subsequently removing at least a portion of the reactive residues. This is usually achieved by extraction from the solid residual product. This extraction is carried out with a hydrogen donor solvent obtained from the solid carbonaceous material that is subjected to liquefaction. The raffinate from the extraction is recycled to the liquefaction step without solvent separation, thereby increasing the overall liquid yield of the process. The normally solid residual product remaining after extraction contains a lower value of carbon than the feed to the extraction process and can be disposed of directly, discarding the unextracted original normally solid residual product. There is less negative impact on economics than in the case of However, as explained fully below,
Maximum conversion rates and maximum thermal efficiencies of solid carbonaceous materials are achieved by combusting or further processing the remaining typically solid residual products to produce useful fuels.

As mentioned above, the present invention relates to an improved liquefaction process for solid carbonaceous materials such as coal, such as coal, coke, etc., where the yield of liquid product is increased with greater thermal efficiency. Liquefaction is carried out at elevated temperatures and pressures in the presence of a hydrogen donor solvent, which produces a liquefied liquid. The normally solid residual product obtained from the liquefaction is extracted using at least a portion of the hydrogen donor solvent used during the liquefaction, and the normally solid residual product is extracted from the normally solid residual product. At least a portion of the carbonaceous material will be present during liquefaction.

In general, the process of the present invention effectively aqueousizes and liquefies 5
It can be used to liquefy any solid carbonaceous material. Solid carbonaceous materials of this type include, but are not necessarily limited to, coal, scrap charcoal, biomass, coke, and the like. The method of the present invention is particularly useful in the liquefaction of coal and can be used to liquefy any coal known in the art, including anthracite, bituminous, subbituminous, lignite, peat, brown coal, etc. can.

Typically, solid carbonaceous materials are ground to a finely divided state.

However, the actual particle size or range of particle sizes used is not critical to the invention, and virtually any particle size can be used. Notwithstanding this, the solid carbonaceous material liquefied according to the present invention generally has a particle size of less than 1/4 inch, preferably a particle size of less than about 8 mesh (M.1-3-S. sieve size). It will be ground up to.

After the solid carbonaceous material is sized, it is slurried with a hydrogen donor solvent. As described in more detail below, at least a portion of the hydrogen donor solvent used to prepare the slurry is used to extract the isogenic residual product from the liquefaction process.

Generally, the solid carbonaceous material is slurried with a sufficient amount of donor solvent to form a solvent-containing slurry. That is, the ratio of the solid carbonaceous material A3-1 is in the range of about 18:1 to about 10:1 based on the amount of N. As used herein, the specific hydrogen donor solvent refers to an aqueous donor bath formed from a portion of the liquefied liquid product, and also includes any non-donor material that may be contained therein.

The hydrogen donor solvent used in the process of the present invention can be any part of the liquefaction product from liquefaction and contains at least f Jo, s g of donor hydrogen, based on the total solvent weight. , or can be processed to contain at least about 0.8 weight percent donor hydrogen, based on the weight of total solvent. A particularly effective solvent is the distillate fraction separated from the liquefied product, from about 350° to about 425°
It has an initial boiling point in the range of about 700°F and a final boiling point in the range of about 700° to below 900°F. Typically, these fractions contain at least about 0.8N based on the weight of total solvent.
Contains a large amount of donor hydrogen, but has a small amount of aromatic substances (
Both have sufficient aromaticity to produce hydrogen donor solvents which can be passed by hydrogenation of a portion to the corresponding hydroaromatic compound.

In this regard, it should be noted that compounds capable of donating hydrogen upon liquefaction are well known in the prior art, and many are described in U.S. Pat. No. 3,867,275. . Compounds that can donate hydrogen during liquefaction include inzone, dihydrofluorin, C4° to C1
2-tetrahydronaphthalene, hexahydrofluorene,
dehydro-, tetrahydrohexahydro- and octohydro-phenanthrene, C12-C13 acenaphthene,
Includes tetrahydro-, hexahydro- and decahydro-pyrene, di-, tetra- and octahydroanthracene and other derivatives of partially saturated aromatic compounds. As is also well known in the art, hydrogenation of each building's coal liquefaction liquid product will produce one or more of these known hydrogen donor compounds.

When starting the process of the present invention and in the event that the solvent produced from the solid carbonaceous material to be subjected to liquefaction is not available, the process may be initiated or operated with any known hydrogen donor compound. can. They can be used as pure compounds or as mixtures of these compounds, alone or in combination with non-hydrogen donating components. Hydrogenated creosote oil can also be used during start-up or in other cases where bathing agents derived from solid carbonaceous materials subjected to liquefaction are not available. Typically, creosote oils are hydrogenated as well as solvents derived from solid carbonaceous materials subjected to liquefied K, a process described in detail below. After slurrying the solid carbonaceous material, the slurry is then heated at a temperature ranging from about 700 to below 950°C and from about 800 m to about
Subject to liquefaction at pressures in the range of o o o psig. Typically, from about 20 to about 100 g of the total solvent used in preparing the slurry is initially used to extract reactive residual products from the normally solid residual products produced during liquefaction. . The solvent contains from about 5 to about 50 pre-reactive reactive residues. Liquefaction is therefore carried out in the presence of about 0.05 to 0.5 parts of reactive residue per 51 parts of coal. During liquefaction, reactive residues are converted into gaseous and liquid products, thereby increasing the total conversion rate of solid carbonaceous material and the yield of normally liquid products.

Upon removal of the liquid, the solid carbonaceous material is converted partly to a normally gaseous product, partly to a normally liquid raw material, and partly to a normally solid residual product. Generally solid residual fJi for one week? I has an initial boiling point in the range of about 900° to about 1100″F and contains unconverted carbonaceous material, inorganic material, and high boiling converted carbonaceous material.

Typically, high-boiling converted carbonaceous materials can be further reduced in molecular weight by further subjecting the residue to liquefaction K or by recycling the entire residue. Similarly, if the residue is subjected to further liquefaction or if the residue is recycled to the liquefaction stage,
At least a portion of the unconverted material could be converted.

The difficult-to-convert portion of unconverted carbonaceous material (Fujinit) is
It will usually not be converted by subsequent liquefaction or recycling of the residue. Similarly, inorganic? ! The lubricant (ash) will also not be converted by liquefaction of the residue or its (1131).

What is surprising here is that when a reactive material is subjected to further liquefaction or is subjected to a liquefaction process, a significant portion of the normally solid carbonaceous material that can be converted to gaseous or liquid products is converted into a normally solid residual product. The residue is found to be separated from the non-reactive parts, ie ash and fusinite, by extraction of the residue with a donor solvent, in particular a donor bath originating from the solid carbonaceous material subjected to liquefaction.

Extraction can be performed under relatively mild conditions.
The extracted reactive portion of the normally solid residual product is converted by recycling it to one or more liquefaction steps. In this case, the conversion of the reactive portion of the normally solid residual product is accomplished with less energy than would be required in subjecting the normally solid residual product to liquefaction in a separate step, and also This is accomplished with less energy than would be required in recycling the residual product. Therefore, the method of the present invention is much more energy efficient than previously proposed methods.

Typically, extraction is carried out at a temperature in the range of 50 to about 600" F and a pressure in the range of about 0 to about 750 psig. Extraction is used to extract the soluble or extractable portion of a normally solid material with a liquid. Extraction is carried out by any suitable conventionally published means which are effective.Normally, extraction is carried out by mixing to maintain good contact between the usually solid residual product and the bath agent used during the extraction. The solvent containing the extracted portion of the usually solid residual product is then removed by any suitable means such as, for example, decantation, centrifugation, week, etc. can be separated from the relatively unreactive parts of the

Of these, gravitational separation followed by decantation is particularly suitable. This is because less energy is required for this particular type of separation. Following separation, the solvent portion can be used directly in the preparation of a slurry of solid carbonaceous material to be subjected to liquefaction. Any solvent that may be entrained in the ash- and fusinite-rich raffinate stream can be removed by flash evaporation or displacement with water. In particular, residual residues with a relatively low carbon content can be discarded.

However, for maximum efficiency, the ash- and fusinite-rich raffinate must be combusted to recover its fuel value, or it can be gasified to produce a hydrogen-containing gas, which can then be used for liquefaction and bath agent fractions. It appears particularly convenient to carry out the hydrogenation of 9. When using a partial oxidation method to perform gasification, the displacement of the entrained solvent by water provides certain advantages.

As noted above, liquefaction typically occurs at temperatures between about 700 and about 900″F.
Temperature in the range of 800~3100ps ig
It is carried out at pressures in the range of . Although any number of liquefaction stages or zones may be used to effect the liquefaction, a single stage is generally preferred.

This is because it reduces the initial casting cost and reduces the energy requirements to perform the liquefaction. The total nominal residence time required is sufficient to liquefy at least a portion of the solid carbonaceous material and generally ranges from about 10 to 200 minutes.

As mentioned above, liquefaction results in a gaseous product, a usually liquid product, and a usually solid residual product.

After liquefaction, these products can be separated into individual phases using conventional techniques. For example, gaseous products can be flushed from the top and liquid and solid products can then be separated using filtration, centrifugation or distillation. Among these, distillation is preferred.

After separation, the gaseous product can be upgraded to pipeline gas or it can be combusted to generate energy for the liquefaction process. Alternatively, all or part of the gaseous product can be reformed to provide hydrogen for the liquefaction process.

The liquid product can be fractionated into virtually any desired product distribution and/or a portion thereof can be used directly as a fuel or upgraded using conventional techniques. . According to the invention, a portion of the liquid product can be separated and used as a solvent or diluent in the liquefaction process of the invention.

This portion of the liquid product may also be hydrogenated to increase the amount of donor hydrogen before using it as a solvent or diluent. Typically, the naphtha fraction is recovered and this naphtha fraction can also be further processed to produce high quality gasoline or similar fuels in the naphtha range.

Finally, according to the improved method of the present invention, at least a portion of the normally solid remaining product is extracted by removing a portion and bringing it into contact with at least a portion of the solvent separated from the liquid product. This solvent containing components extracted from the residual product of is used to produce a solid carbonaceous material slurry, which is ultimately subjected to the liquefaction process of the present invention. Typically, from about 1 to about 6 parts by weight of solvent or diluent per part of normally solid residual product are contacted with the residual product of the extraction step. This extraction results in approximately 20 to 20% of the reactive portion of the residue.
Approximately 80 tons are usually separated from the solid residue during the extraction. Then, the slurry preparation is adjusted, and about per part of a solid carbon material supplied to the liquefied process or bandwidth.
05 to about α5 parts of “reactive component” is provided.

In preferred embodiments of the invention, the coal has a molecular weight of about 80 to about 880
Temperatures in the range of °F and about 1500 to about 2,000 ps
It is liquefied in a single step liquefaction operation at pressures in the range of ig. In a preferred embodiment, the coal is slurried with a solvent or diluent fractionated from the liquid product of coal liquefaction;
The solvent contains at least 45% by weight hydrogen donor material and is hydrogenated to contain at least 125 tes of donor hydrogen. All of the solvents used in preparing the slurry are used to extract the reactive substances from the usually solid residual products produced during liquefaction.

The prepared slurry, when fed to the liquefaction step or zone, contains from about 0.1 to about 0.5 parts of reactive material from the residual product per part of coal. The ratio of solvent to coal in the slurry ranges from about 1=1 to about 5:1. Nominal residence times during liquefaction range from about 40 to about 140 minutes. In a preferred embodiment, the extraction is carried out at a temperature ranging from about 100 to about 4000 psig and a pressure ranging from 0 to about 50 opsig.

Contact between the solvent and the normally solid residual product is from about 4:1 to about 8:1 (v/v) in a countercurrent baffled contact vessel.
The ratio of solvent to residual product, which is usually solid, is in the range of . In a preferred embodiment, the baffled contact vessel is arranged vertically, so that the bath agent flows upwardly and the normally solid residual product settles downwardly. The solvent is then withdrawn at or near the top of the buckle contact vessel, and the residual product, which is usually solid and does not contain extracted reactive substances, is withdrawn at or near the bottom.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings. Referring to FIG. 1, a solid carbonaceous material such as fine coal is introduced into a mixing vessel 10 via path 11 and slurried with a hydrogen donor solvent or diluent introduced via path 12. . In a preferred embodiment, the solvent is all or a portion of the distillation fraction separated from the liquefied liquid product, and this fraction is hydrogenated to produce a bath agent containing less (by weight -45%) hydrogen donor material. , which is used to extract the reactive solid carbonaceous material from the usually homogeneous residual product.If not all of the bath is used in the extraction process, the additional solvent required to effect the liquefaction is added to route 13. However, during start-up, or if a circulating solvent is not available, any known useful hydrogen donor solvent or diluent can be introduced into line 13 via line 14.

In the mixing vessel 10 and if a normally solid residual product is available, a solid carbonaceous material such as coal is further mixed with the reactive material extracted from said residue. In the illustrated embodiment, the reactive substance is contained in a solvent fed into mixing vessel 10 via line 12. In a preferred embodiment, the reactive material and the solid carbonaceous material are separated from each other by about o,
Mix at a ratio of i:1 to about O, S:1 (by weight). The reactive material and solid carbonaceous material are mixed with sufficient solvent, including that used in the extraction process, and introduced into mixing vessel 10 via line 12 to provide a solvent to solid carbonaceous material ratio of 4: A slurry ranging from 1 to about 8:1 is produced.

In the illustrated embodiment, the slurry is withdrawn from the mixing vessel 10 via path 16 and passed into a preheater 17. In preheater 17, the slurry is heated to the desired temperature, typically about 50 to about 100'F below the temperature at which liquefaction occurs. If desired, water vapor is flashed from the top via path 18, especially if the solid carbonaceous material has not already been previously dried.

Typically, a slurry of solid carbonaceous material is mixed with molecular hydrogen. In a preferred embodiment, molecular hydrogen is added via path 19 prior to preheating.

However, this is not critical and the hydrogen can also be added downstream of the preheater 17 or directly into the liquefaction vessel. In any case, the hydrogen is introduced after the water vapor has been flushed from the top. In a preferred embodiment, the hydrogen is produced by steam reforming of the gaseous product from liquefaction or by gasification of the non-reactive part of the solid residual product or by gasification of solid carbonaceous material in a separate step; All can be done by conventional techniques. Generally, from about 2% to about 10% by weight, preferably from about 3% to about 8% by weight, based on dry solid carbonaceous material.
enough to give molecular hydrogen of 7*””14)y8h7
: , , , , , □ The slurry is extracted from the preliminary heater through the path 20 and directly transferred to the liquefaction container 21 .

In the liquefaction vessel 21, the solid carbonaceous material is at least partially liquefied and at least partially gasified, usually without the presence of any conversion catalyst. Preferably, the liquefaction vessel has a capacity of about 40
A single vessel is used in the preferred embodiment, sized to provide a nominal residence time in the range of ~140 minutes.

Furthermore, the temperature within the liquefaction zone 21 is preferably about 8
The temperature ranges from 0.00 to about 880 degrees Fahrenheit, and the pressure is preferably adjusted to within the range of about 1,500 to about 2.000 psig.

In the illustrated embodiment, the mixed product from the liquefaction vessel 21 is withdrawn via path 22 and transferred to separation means 25 . In the illustrated embodiment, it may be a mixed atmospheric and reduced pressure distillation column, with gaseous products and products having a boiling point below the naphtha boiling range being withdrawn from the top via line 24, while unconverted solid carbon The raw materials, inorganic materials, and convertible materials having an initial boiling point in the range of about 95° F. to about 1050° F. are withdrawn through seven filters 25. The liquid product is then fractionated into the desired fractions. , in the illustrated embodiment with an initial boiling point of about 150"F and about 350"F.
A naphtha product having a final boiling point ranging from below about 425 degrees Fahrenheit is withdrawn via line 26.

With an initial boiling point ranging from about 350°F to about 425'F and about 65
A metal distillation fraction having a final boiling point in the range of 0'F to about sso''F is withdrawn via path 27, and a metal distillate fraction having an initial boiling point in the range of about 650T to about 850''F'' and about 950
Vacuum gas oil horn having a final boiling point in the range of 1050°F to about 1050°F is withdrawn via line 28.

Typically, the gaseous substances at the top of the column are the gaseous bottom hydrocarbons, water vapor, carbon oxides, acidic gases such as S02 and H2S, any ammonia produced during liquefaction, and any ammonia not consumed during liquefaction. It consists of all hydrogen.

This stream is cleaned and further split to produce high Btu gas, light hydrocarbons, and hydrogen. Generally, all hydrogen recovered from this stream is reused in the liquefaction or hydrogenation process. The naphtha stream can be further upgraded to obtain good quality gasoline, the heavy stream withdrawn via path 28 can be upgraded to produce heavy fuel oil, or hydro It can also be cracked and refomed to produce a gasoline boiling point fraction. Generally, the solvent boiling range material, or at least a portion thereof, is catalytically hydrogenated to increase the concentration of glacial donor material, and then at least a portion of the hydrogenated fraction is used to remove the normally solid residue via route 25. Reactive substances are extracted from a small portion of the product.

As noted above, the particular separation mode used is not critical to the invention, and virtually any separation technique known in the art can be used to effect the separation of gas, liquid, and solid products. For example, the gaseous product can be flashed directly after liquefaction, and the liquid-solid mixture can then be subjected to separation by distillation, filtration, extraction, centrifugation, etc. However, in both cases the residual product containing unreacted coal, inorganic substances and high-boiling hydrocarbons can be used for extraction with a solvent separated from the liquefaction preparation.

In a preferred embodiment, the solvent fraction withdrawn via path 27 is hydrogenated before its use as either an extraction solvent or a liquefaction solvent or diluent.

Preferably, the hydrogenation is carried out catalytically under conditions conventionally said to be effective for this purpose. In the embodiment shown, the hydrogenation takes place in the hydrogenation vessel 29 with a molecular water system introduced from path 3°.

The hydrogen actually used may be from any source, in preferred embodiments from the steam reforming pressure of at least a portion of the gaseous product from liquefaction, or from the normally solid residual product. or by gasification of a portion of a solid carbonaceous material that is subjected to liquefaction. In the embodiment shown, unreacted hydrogen and the gaseous products of the hydrogen reaction are withdrawn via line 61. If desired, this gaseous product can be processed to recover the hydrogen. Additionally, in the illustrated embodiment, the hydrogenation product is withdrawn via line 32. The hydrogenation product includes a portion of the solvent used in the extraction step, a portion of the solvent that is returned directly to the mixing vessel 1o, and any excess bath agent that may be produced. The portion of the hydrogenation product to be used as a solvent during the extraction is removed via line 39, and the remaining portion of the hydrogenation product is removed via line 32'. Via route 33, excess bath agent can be extracted and stored as product for future use in liquefaction. If desired, a portion of the solvent supplied directly to the mixing vessel 10 is circulated via line 13.

Typically, the hydrogenation is carried out at temperatures ranging from about 600'F to about 950F and pressures ranging from about 600 to about 2.000 psig, preferably from 1.000 to about 500 psig. The hydrogen treatment rate excluding hydrogenation is generally about 1, ODO to about 10. OD Oscf/bbl
is within the range of

Although any known hydrogenation catalyst may be used, nickel molybdenum catalysts are particularly preferred.

According to the improved method of the invention, the residual product withdrawn via route 25 can be divided and subjected to extraction in whole or in part.

The portion to be subjected to extraction is withdrawn via channel 34 and fed to contact vessel 40 . In a preferred embodiment, all of the normally solid residual product is passed into contact vessel 40. Any portion of the residual product that has not been subjected to extraction can be withdrawn via route 35 and processed according to conventional techniques. −
From about 80 to about 1 ooins of grain pressure, residual product is lost to extraction.

In contact vessel 40, a fraction of the hydrogenation product from hydrogenation vessel 29, used as an extraction bath, is introduced at or near the bottom of contact vessel 40, which flows upwardly through the contact vessel and at its top. It is extracted via the path 41 at or near the area. The residual product introduced through line 34 generally flows downward and is withdrawn from the contact vessel at or near its bottom via line 341. In the illustrated embodiment, the solvent containing the reactive substances withdrawn and extracted via path 41 is then passed through a knockout drum 42 to separate out any unreacted substances contained therein. make it easier. Unreacted substances are routed from the knockout drum 42 to a path 43'.
separated via.

The non-reactive substances separated in the knock-out drum can then be mixed with the non-reactive substances separated from the contact vessel 4o by medium pressure in the path 43 and introduced into the separator 46. In the separator, the entrained solvent can be flashed overhead and the remaining portion of the normally solid residual product can be withdrawn via line 48. The recovered solvent (not shown) can be mixed with the solvent withdrawn from the knockout drum 42 or
can be mixed with the solvent drawn off from the hydrogenation vessel 29 via the hydrogenation vessel 29. In general, solvent free of non-reactive substances is withdrawn from the knockout drum 42 via path 12 and fed to the mixing vessel 1°. The remaining portion of the normally solid residual product withdrawn via line 48 is disposed of directly or may be treated according to conventional techniques to recover its energy.

As mentioned above, in the preferred embodiment, the extraction is fJl
Temperatures in the range of 0 to about 400″F and about 0 to about 500″F
It is carried out at pressures in the psig range. In the illustrated embodiment, the processing rate 1 W in the contact vessel 40 ranges from about 4 to 8 v/v/krr. Although not shown, the contact container 40 can be a stirring container,
All of the solvent/usually solid residual product can be withdrawn and transferred to a gravity separator.

The main portion of the solvent can then be drawn off and separated from the decantation vessel at a point above the solids level. The solvent entrained in the remaining solid portion can then be separated off as described above. When using a stirred vessel, the space velocity is not directly mounted, but approximately 20
Sufficient contact time should be provided to ensure separation of ~f180% by weight from the normally solid residual product.

The reactive substances separated in this way are recovered with less energy than would be required using more common solvents such as toluene, and conventional bath agents are generally separated and processed in the liquefaction process. It is reused for extraction operations rather than as a bath agent.

Although the present invention and its preferred specific pH have been broadly described above, this will become clearer with reference to the following examples. However, these examples are for illustrative purposes and
It is not intended to limit the invention in any way.

Example 1 In this example, Illinois seam coal (Illinois 1Nn6)' is used in a 10'0 pound per day continuous unit.
A hydrogenated material having an initial boiling point of about 400'F and a final boiling point of about 800'F and containing from about 40 to about 45% by weight hydrogen donor material. The circulating liquid was used as an extraction bath and as a liquefaction solvent or diluent.The apparatus was operated in a manner similar to that shown in FIG. The residual product was extracted from the separation vessel. When withdrawn, the residual product contained 40% of toluene soluble material. The residue was nominally contacted with a hydrogen donor bath at a temperature below 600 °C and a pressure of Opsig. The extraction time was 5 minutes. After extraction, the remainder of the usually solid residual product contained 10% by weight of toluene soluble material.

Therefore, the use of a solvent for the purpose of slurry preparation to extract the residue can remove approximately 75% of the reactive material from the residue.
weight recovery with a corresponding increase in gaseous and liquid product yields.

Example 2 In this example, tests were conducted using 100 pounds per day continuous equipment, using Wyodac coal as the solid carbonaceous material, and with an initial boiling point of about 40011' and about s
oo'F and about 40 to about 45 wt%
The hydrogenated recycle liquid containing hydrogen donor material was used as extraction solvent and as liquefaction solvent or diluent. The apparatus was operated in a manner similar to that illustrated in FIG.

All of the solvent withdrawn from the hydrogenation vessel 29 was used to extract the residue from the separation vessel. When drawn off, the residue contains 50% by weight of toluene soluble material. The residue was treated with a hydrogen donor bath at a temperature of 300'F and Op.
Extraction was performed at a pressure of sig with a nominal contact time of 5 minutes. After extraction, the remaining portion of the usually solid residual product contained over 10 ml of toluene soluble material. Therefore, the use of a solvent intended to extract the residue from the slurry results in a recovery of about 80% by weight of the reactive substances from the residue, with a corresponding increase in the yield of gaseous and liquid products. It increased.

As is clear from the above, the total conversion rate of 1 coal is approximately 10 to 1
The yield of both gaseous and liquid products was also increased. This increase is required when using a zero force liquefaction process, or when recycling the entire residue, or when using a solvent to extract the residue and then separating it by distillation. This was effectively achieved using less equipment and less energy than was originally proposed.

Although the present invention has been described and illustrated with respect to specific specific examples,
It will be understood by those skilled in the art that the present invention is susceptible to modifications within its scope. For this reason, reference should be made only to the claims for purposes of determining the scope of the invention.

[Brief explanation of the drawing]

FIG. 1 is a schematic flow chart of a method within the scope of the present invention. 10: Mixing container 17: Pre-heater 21: Liquefaction container 23: Separation means 29: Hydrogenation container 40: Contact container 46: Separator 4.

Claims (8)

[Claims] (1) (a) producing a slurry of solid carbonaceous material such as coal in a hydrogen donor solvent; 1 part to the usual liquid product K and 1 part to the usual solid residual product (C1 the usually gaseous product, the usually liquid product and the usually solid residual product) and process t
(d) extracting at least a portion of the normally solid residual product with a donor solvent; and at least a portion of the extract phase from the extraction in step (dl) being carried out in step (b) An improved method for liquefying a solid carbonaceous material such as coal, characterized by: circulating it through liquefaction. 2. Process according to claim 1, characterized in that the donor solvent is a distillation fraction separated from the liquid product obtained in step (C1). 3. Process according to claim 2, characterized in that a small portion of the distillation fraction used as donor solvent is used for extracting residual products in the step (diK). (4) The extract phase from the extraction of step (dl) was transferred to the extract phase from the step (al
4. The method according to claim 1, wherein at least a part of the solvent is used in preparing the slurry. (5) The extraction of step (d) is carried out at a temperature in the range of about 50 to about 6 oooF and a pressure in the range of about 0 to about 750 psig! jiFF The method according to any one of claims 1 to 4. (6) % i?, characterized in that the ratio of solvent to normally solid residual product is in the range of about 4=1 to about 8:IV/V. 'The method according to any one of items 1 to 5 of the range of FM determination. (7) A method for liquefying carbonaceous materials, such as coal, substantially as herein described with particular reference to the examples and drawings. (8) A liquid product produced by the method according to any one of claims 1 to 7.