US3109803A - Process for producing substantially ash-free bituminous coal, subbituminous coal andlignite - Google Patents

Description

W. J. BLOOMER Nov. 5, 1963 ETAL 3,109,803 LY ASH-FREE BITUMINOUS UMINoUs COAL AND LIGNITE PROCESS FOR PRODUCI SUBSTANTIAL COAL, SUBBIT Filed Aug. 5, 1959 INVE NTORS Bl. OMER WARD J. SAMUEL M M R TIN (0E CE A $50) BY BEVERLY 8. MART/N, ADMINISTRA TIP/X AGENTS* United States Patent O 3,109,863 PRCESS FR PRUDUCHTQIG SUBSTANHALEJY ASH-FREE BiTUMENQUS CAL, SUBBHU- MENUS CAL ANB MGNHTE Ward J. lioomer, Westiield, NJ., and Samnei W. Martin, deceased, late of @air iarlr, ill., by Beverly B. Martin, administratrix, @fait Pari-r, lil., assignors to The Lummus Company, New York, NY., a corporation of Deiaware Fitted Aug. 3, 1959, Ser. No, 331,312 6 Claims. (Cl. 20d-S) This invention relates to a process for producing useful carbonaceous matter from coal and more particularly relates to a method of producing substantially ash-free coke from a de-ashed solution of carbonaceous matter prepared from a coal selected from the group consisting of bituminous coal, subbituminous coal and lignite. This application relates to our co-pending applications Serial Nos. 831,310 and 831,311, led on the even date herewith.

Presently, most calcined anode carbon is produced from petroleum coke, with the remainder being produced from the coke obtained by carbonizing coal tar pitches. Considering the steadily increasing consumption of petroleum coke for manufacturing carbon anodes, coal represents a large potential source of coke suitable for such purpose.

Coal is primarily comprised of three-dimensional, condensed, cyclic structures of high molecular weight, such structures being predominantly six-membered rings. Bituminous coal has been considered an intimate mixture of bitumen and humin which are similar in that both are large, flat aromatic lamellar structures, but differ in molecular size, degree of aromaticity, oxygen content and the extent of cross linking.

Mineral matter, fusain and volatile matter and moisture primarily constitute the remaining components present in coal. Mineral matter deposited in the sedimentary deposits by inliltration of ground waters during coaliication and remaining after coal has been burned is called ash. Fusain, which is substantially consumed during the combustion of coal may be considered a mineral charcoal.

The rank of coal (i.e. the degree of coalification) is determined by its carbon content which increases with the natural series of lignite, subbituminous coal and bituminous coal. In this series, the fixed carbon content generally increases whereas the moisture and oxygen content decreases.

The presence of fusain, mineral matter (analyzed as ash) and combined sulfur is the primary reason for the lack of utilization of coal for preparing coke suitable for making anodes to be used in the production of aluminum. Sulfur is usually present as organic sulfur, pyritic sulfur and/or inorganic sulfate. It is known that the ratio of inorganic sulfate and pyritic sulfur to organic sulfur increases with coals of increasing total sulfur content.

The following processes have been suggested for reducing fusain or mineral charcoal and minerai matter or ash present in various types of carbonaceous materials:

(l) Specific gravity separation or beneciation--a method of separating the materials having a low specific gravity from the heavier materials which contain a substantial portion of the ash and fusain.

(2) Flotation and electrostatic separation a process based on the differences between the surface properties of a coal particle and that of an ash particle.

(3) Chemical extraction of the ash-a process wherein the ash present in the raw coal is subjected to chemical attack, usually by an acid or alkali, to form soluble chemicals which are readily leached from the treated coal.

(4) Solvent extraction-a process wherein the coal substance is dissolved or extracted from the raw coal with a solvent to form a coal extract solution. The insoluble ddd-ddd@ Patented Nov. 5, M1863 d components, viz., fusain or mineral charcoal, mineral matter or ash and some of the other impurities remain substantially unchanged and are consequently suspended in the solution. The components are thereafter separated from the solution by filtration, decantation or the like.

One solvent extraction or soivation process for preparing a coal extract practiced in the past is referred to as the Pott-Broche process, named after Alfred Pott and Hans Broche. As described in their US. Patent No. 1,881,927, a coal extract was prepared by treating one part of a carbonaceous material, such as pitcoal, lignite, peat and the like with two parts tetraline at a temperature of from 320 to 490 C. and at a pressure of about 100 atmospheres to dissolve the coal substance. The minimum temperature of extraction was determined by the decomposition temperatures of the initial coal. The insoluble and undissolved particles were separated from the coal solution by centrifugation and the tetraline was thereafter distilled from the solution to provide a coal extract which had a substantially smaller quantity of ash as compared to the weight percent of ash originally present in the raw carbonaceous material. The separation of the insoluble and undissolved particles from the solution was later found to be more effectively performed by passing the coal solution through a multiplicity of ceramic lter candles. Solvent iosses occurring during the separation are one of the problems attending this technique of separation as well as other techniques for separating mineral charcoal or fusain, and mineral matter or ash and like impurities from the solution. Another problem is the coking of the various process lines during extraction and separation.

In U.S. Patent No. 2,166,321 Pott described a process for utilizing the coal extract obtained by the aforementioned process to produce a semi-coke or full coke. The semi-coke or full coke was produced by blending the coal extract with a semi-coke (previously produced by the process) and charging the resultant mixture to a coke oven. The mixture was heated in the coke oven to a temperature of from 450 to 1100 C. to produce the semicoke or full coke depending on Whether a low or high temperature, respectively, was maintained in the coking oven. The coke product withdrawn from the coke oven had a low ash content and was suitable for use as a metallurgical coke for manufacturing electrodes.

it is a principal object of our invention to provide a novel method for preparing substantially ash-free coke from a coal selected from the group consisting of bituminous coal, subbituminous coal and lignite.

A further object of our invention is to provide a novel method for preparing not only substantially ash-free coke but also valuable products, such as gas, aromatic solvents and oils, and ammonia from a coal selected from the group consisting of bituminous coal, subbituminous coal and lignite.

A still further object of our invention is to produce substantially ash-free coke from a de-ashed coal solution prepared from a coal selected from the group consisting of bituminous coal, subbiturninous coal and lignite.

Further objects and a fuller understanding of our invention may be had by referring to the following description taken in conjunction with the accompanying drawing, in which the figure is a schematic flow-diagram illustrating a preferred embodiment of the invention for producing substantially ash-free coke.

Prior to treatment in our novel process, the raw coal yto be treated is crushed and ground in conventional crushing and grinding equipment. The particle size distribution may range up to l0 mm., however, we prefer a particle size distribution whereby a major portion of `the coal particles pass through a mesh screen.

ln Iaccordance with our invention 'we propose to digest and/ or dissolve the extractable carbonaceous matter (which exclu-des fusain) present in the pulverized raw coal under conditions of elevated temperatures and pressures utilizing a high boiling liquid solvent of high aromaticity thereby forming a solution of such extractable carbonaceous matter (hereinafter referred to as a coal solution). Fusain and the mineral matter or ash are substantially unaffected by the solvent and are suspended in the coal solution.

The coal solution while in a free flowing state is filtered to separate the suspended insoluble solids (including undissolved extractable carbonaceous matter) and is thereafter heated to a temperature above incipient coking `and passed to a coking unit. Product coke is withdrawn from the cok-ing unit and passed to subsequent processing units including coke handling and calcining facilities. The vaporous products are withdrawn from the coking unit yand are introduced into a fractionating unit wherein they are separated into various fractions, such as, for example: a light gas and gasoline fraction; a medium and heavy middle oil distillate fraction; and -a heavy bottoms distillate fraction. A portion or all of the high boiling liquid solvent of high aromaticity utilized for dissolving or digesting the extractable carbonaceous matter present in the raw coal is derived from a distillate fraction recovered from the fractionating unit.

In preparing the coal solution, we prefer to use a ratio of high boiling liquid solvent to raw coal of from about 2:1 to about 3:1, however, a ratio range of from 1/211 to 6:1 may be used. A lower ratio within the range of from zzl to about 11/2z1 does not as eliiciently dissolve or digest the extractable carbonaceous matter whereas a higher ratio within the range of from yabout 3:1 to 6:1 places a heavier load on the filtration unit and renders filtration uneconomical. Further, high solvent ratios place an :additional heat load on subsequent heating apparatus as a result of additional Vaporization requirements.

Solvation or digestion of the extractable carbonaceous matter is accomplished in a solutizer or solvation vessel at throughput times varying vfrom about to 120 minutes. A temperature of from about 750 to 825 F. and above the final decomposition temperature (where there is substantial heat decomposition of the extractable carbonaceous matter) of the initial ycoal is preferably maintained in the solutizer. It is believed that within this temperature range, the cyclic, three-dimensional components of the coal are thermally depolymerized with the resulting constituents Ibeing soluble in the solvent. The coal solution which is formed has physical properties similar to those of low temperature carbonization coal tar pitches. AOperating within this temperature range, we have `dissolved more than 95% of the extractable carbonaceous matter based on the available ash-free, fusainfree and sulfur-free coal. -Digestion or solvation may be performed at temperatures of from 600 to 850 F. however operating at the lower temperatures within this range has the disadvantage of dissolving a substantially .smaller portion of the extractable carbonaceous matter whereas polymerization of the high boiling solvent and the coal solution has been observed at temperatures above about 825 F. `For effective and eiiicient solvation, polymerization of both the coal solution and the highly aromatic solvent must be minimized. A pressure range of about 1 to 7 or 8 atmospheres is preferably Ymaintained on the solutizer, however the solutizer may be operated at pressures up `to 100 atmospheres. The preferred pressure range is substantially lower than pressure ranges previously required, since the solvent has a higher boiling range as compared to the solvents, such as coal tar, water gas tar, tetraline, phanthrene and anthracene oil which have been heretofore suggested for solvation of theV extractable carbonaceous matter.

Filtration (including conventional `dewatering, washing and drying of the filter cake) of the coal solution is performed at a temperature of from about 400` to 700 F.

i utilizing a metallic filter medium precoated |with a conventional filter aid. PrecoatingV the lter substantially improves the separation of undissolved and insoluble particles from the coal solution. With a precoated filter, we have prepared filtered coal solutions which when analyzed for ash only varied between 0.08 to 0.02 weight percent, irrespective of the ash content of the raw coal which varied from 1 to 20 percent.V This indicated that the efficiency of de-ashing by filtration was a function of the size of the ash particle rather than the ash content. Using conventional diatornaceous earth filter aids, the combustible carbonaceous matter of the filter cake is suliicient to permit its further use as fuel for process steam, and the like. Carbonaceous filter aids permit still Ifurther heat recovery from the filter'cake.

The sulfur content of low sulfur coals (i.e. about 1.0 to 2.0 weight percent sulfur) has been reduced to values of from 0.4 to 0.6% which represented an average reduction of about 70 percent. Since the organic sulfur present in the raw coal is readily soluble in the highly aromatic solvent, the quantity of sulfur separated from the raw coal is a function of the pyritic and sulfate sulfur content of the `coal with the final sulfur content of the filtered coal solution primarily being a function of .the organic sulfur content of the coal. With high sulfur coals, the ratio of inorganic sulfate and pyritic sulfur to organic sulfur is normally greater than for low sulfur coals. Consequently, with high sulfur coals, we have observed a greater percentage-wise reduction of the sulfur content, reducing the sulfur content of the filtered coal solution to as low as 0.6 weight percent, which corresponded to an over-all reduction of the sulfur content of from 70 to 90%.

The filtered coal solution is readily coked in any conventional coking unit used for cokng petroleum feed stocks by heating the solution to a. temperature above its incipient coking temperature and thereafter coking the solution to produce substantially ash-free coke having a wide range of volatile matter, i.e. of about 4 to 26%.

We prefer to coke the coal solution in a delayed Acoking unit basically comprised of coke drums. Utilizing such a unit, the filtered coal solution is heated to a temperature of from about 850 to 1050 F. and is introduced into one of the coke drums. The lower limit above the incipient coking temperature to which the coal solution is heated is dictated by the upper limit of the volatile matter desired in the coke product, normally about 8 to 16%. The upper limit above the incipient coking temperature to which the coal solution is heated is dictated by the lower limit of the volatile matter desired in the coke product, normally about 6 to 8%, since coke having less than 6% volatile matter is extremely hard and is consequently difficult toremove from the coke drum.

The coal solution may also be coked in a contact coking unit (comprised of a reactor having a downwardly flowing bed of a particulate material on which the feed is spread and coked) and at higher temperatures so as to produce a coke having less than 6% volatile matter. Higher temperatures are permissible using a contact coking unit since there is not the practical limitation of decoking a drum filled with coke of less than 6% volatile matter. Further, contact coking procedures do not Vrequire preheating of the coker feed to a temperature above its incipient coking temperature, since the feed may be heated in the colter to a temperature above incipient coking by the sensible heat of the contact particles.

T he fractionating unit is controlled under conditions of temperature and pressure to provide all or a portion of the highly aromatic liquid solvent for the solvation of the coal. The initial boiling temperature (converted to one atmosphere) of such solvent is from 650 to 850 F. and has physical properties similar to that of a low temperature tar distillate. It has been observed when processing bituminous coal that sufficient solvent (for a 2:1 to 3:1 ratio of solvent to coal) is usually obtained from the fractionating unit by operating the unit to provide a distillate having an initial boiling temperature (converted to one atmosphere) of about 750 F. The fractionating unit is preferably operated at from 1 to 7-8 atmospheres, however, it is generally contemplated that pressures up to 100 atmospheres may be maintained on the unit. The solutizer, may be considered to be an extension of the fractionating unit, but it is not necessary to operate both the fractionating unit and solutizer at the same pressure. Generally the overall level of pressure in the solutizer will be at some higher pressure than the fractionating unit because of the normal increase of solutizer temperature over tower bottoms temperature and because of the presence of some lower boiling coal decomposition products formed in the solutizer. Solvent requirements may necessitate a higher pressure on both units to provide more solvent from the fractionating unit by the inclusion of light ends normally lost to side streams and/or overhead when operating the fractionating unit at lower pressures.

Referring to the drawing, ground or pulverized coal selected from the group consisting of bituminous coal, subbituminous coal and lignite, and/or mixtures thereof are collected in a hopper 1 from which it is distributed at a desired rate by a conveying mechanism 2 into a solutizer tank 3 maintained at a pressure of from about l to 7-8 atmospheres. As illustrated, conveying mechanism 2 is a screw type feeder which introduces the feed into solutizer 3 without loss of pressure therein. Any conventional means of mechanical transfer may suffice, providing the means allows for positive transfer of the coal into solutizer 3 without a substantial loss of pressure therein.

The high boiling liquid solvent of high aromaticity is introduced into solutizer 3 through line 4 at a rate so as to provide a ratio of solvent to coal of from 1/2:1 to 6:1. Normally, we prefer a solvent to coal ratio of from about 2:1 to about 3:1, since effective extraction rates are obtained within this ratio range while minimizing filtration costs. Solutizer 3 is maintained at a temperature of from about 600 to 850 F., preferably of from about 750 to 825 F. and above the final decomposition temperature of the initial coal, whereby a substantial portion of the extractable carbonaceous matter in the raw coal is thermally depolymerized. The products of depolymerization are soluble in the highly aromatic solvent and thereby form, with the solvent, the coal solution. Undissolved and insoluble solids including undissolved extractable carbonaceous matter, and insoluble mineral matter or ash and mineral charcoal or fusain are suspended in the coal solution. An agitator (not shown) may be provided to agitate the coal-solvent mixture during solvation.

Solvation temperatures are maintained in solutizer 3 by withdrawing and circulating a portion of the coal solution and/ or coal-solvent mixture through an external heating system. The withdrawn portion is passed through line 5 by pump 6 under the control of valve 7 to heater 8 and thereafter reintroduced through line 9 into solutizer 3. In this manner, solvation temperatures are maintained within solutizer 3 without the necessity of a high temperature and pressure heating system, which would be the case, if the solvent was preheated to a temperature sufficient to maintain solvation temperatures within the solutizer. A through-put time of the raw coal of from 5 to 120 minutes is normally suicient to dissolve or digest effectively and eiciently the extractable carbonaceous matter. Since the solvent may have an initial boiling temperature (converted to one atmosphere) as low as 650 F., whereas solvation temperatures may be as high as 850 F., solutizer 3 is provided with vent line 10 under the control of valve 11 to permit the Withdrawal of the lower boiling components of the solvent and any volatile matter vaporized from the raw coal. In this respect, it has been observed that the quantity of volatile matter is practically negligible. A substantially uniform coal solution, wherein undissolved and insoluble solids are suspended, which include mineral charcoal or fusain and mineral matter or ash, is withdrawn through the bottom draw-off 12 and is drawn through cooler 13 by pump 14 and passed to a continuous rotary filter 15.

The coal solution is cooled to a temperature of from about 400 to 700 F. during its passage through cooler 13. Preferably, the rotary lter 15 is precoated with conventional lter aids and is normally operated at a pressure of about 40 to 60 p.s.i.g. to effect efficient removal of substantially all of the suspended solids including undissolved carbonaceous matter. The filter cake is washed and dried to recover adsorbed solvent and is withdrawn from filter 15 through line 16. The substantially de-ashed coal solution is passed through line 17 to surge drum 1S from which it is passed through line 19 and pump 20 to heater 21 (a suitable coil heater). The coal solution is heated to a temperature of from about 850 to 1050 F. in heater 21 and is passed therefrom through line Z2 to a coking unit.

The coking unit, as illustrated, is a delayed coker and is comprised of coke drums 23 and 24. The heated coal solution in line 22 is introduced through line 22a into colter 23 wherein the charge is decomposed into colte and a vaporous effluent. The coker overhead in. line 25a is passed through line 25 to a fractionating unit. While Coker 23 is being filled with coke, coker 24 is being decolted with product colte withdrawn through lines 26a and 26 for subsequent processing. In normal operation, cooling and decoking of coker 24 is completed prior to the filling of the colrer 23. With the decoking completed on Coker 24 and having filled coker 23 to a predetermined level, the coker charge is diverted to colter 24 through line 22h, with the vaporous effluent in line 25b being passed to the fractionating unit through line 2S. After cooling, coker 23 is decoked with product coke being passed through lines 26b and 26 for subsequent processing.

rIhe coker overhead in line 25 is introduced into a fractionating or combination tower 27 which is provided with suitable fractionating decks (not shown). Introduction of the etiiuent into the tower may result in some foaming. This may be effectively inhibited by the addition of a small amount of an anti-foam agent, at the point of introduction or at some elevated point in the tower. The hereinbefore mentioned distillate and volatile matter in line 10, which are evolved during solvation, are introduced into the lower portion of the tower 27.

The combination tower overhead products in line y23 comprising condensible and non-condensible components are passed to conventional processing units to separate the condon-sible components from the non-condensible components. A medium and heavy middle oil is Withdrawn from an intermediate point on the tower 27 through line 29 by pump 30 and is passed .through line 31 to refining units (not shown). A portion of the middle oil in line 29, under the control of valve 32, is passed through line 35, waste heat boiler 34, and line 35 and is thereafter split into at least two portions (lin-es 35a and 3515) for introduction as reflux into tower 27.

Tower bottoms in line 36 are passed to surge tank 37. By properly controlling the temperature level within tower 27, the distillate fraction in line 36 has an ititial boiling temperature (converted to one atmosphere) of from 650 to 850 F. and represents all or a portion of the solvent to be used for dissolving or digesting the extractable carbonaceous matter in the pulverized raw coal feed. As hereinbefore mentioned, when processing bituminous coal, solvent requirements may usually be satisfied by operating the -fractionating unit so as to obtain a distillate having an initial boiling temperature (converted to one atmosphere) of about 750 1F. If additional solvent is required (over the 750 F. distillate) the fractionating unit may be operated to provide a distillate having an initial boiling temperature (converted to one atmosphere) as low as 650 F. or desired, the fractionating unit may be operated to provide the latter distillate, withdrawing excess solvent over -solutizer requirements for utilization in other processes.

. 37 is superfluous.

Start-up or malte-up solvent is introduced into sunge tank 37 through line 38 under the control of valve 39. The quantity of solvent necessary to provide .a solvent to coal ratio of from 1/2 :1 to 6:1 is Withdrawn from tank 37 through line 40 and passed by pump 41 under the con- 5 trol of valve 42 into line 4. After start-up, should the quantity of captive solvent exceed solvation requirements, excess solvent may be withdrawn from tank 37 through line 43 under the control of valve 4.4. It is generally contemplated that solvent requirements for the solvation of bituminous coal maybe fulfilled by controlling the operating temperature and pressure of the combination tower so as to permit the'direct introduction of the distillate fraction inline 36 to solutizer 3, in which case, surge tank The following examples will further illustrate the nature o-f this invention, it being understood that the invention is not limited to the operating conditions or quantities therein:

Example l In accordance with our invention a bituminous coal having the following proximate analysis:

were introduced into the solutizer zone to provide a 3 to 1 ratio of solvent to coal. The mixture was agitated while maintaining a temperature of 800 F. and a pressure of 5 atmospheres. The resulting coal solution was cooled to a temperature of 450 and passed through a filter precoated with a standard lter aid. The filtered coal solution represented an 86.3% recovery of extractable carbonaceous matter based on the crushed coal and had the following properties:

Properties: 45 Sp. gravity (100/100 iF.) 1.2407 Softening point, F. (B+R) 152 Sulfur (wt. percent) 0.46 Carbon residue (wt. percent)- Ramsbottom 30.9

Conradson 3 1.3 CS2 solubility (-wt. percent)- Bitumen 76.66

Ash 0.02

Difference 23,22

The filtered coal solution was heated to 910 F. and coked to provide a coke which was recovered from the coker having the following properties:

Properties: Wt. percent Volatile matter 10.9 Sulfur 0.27 Ash 0.13 Iron 0.036 Silicon 0.009 R203 0.112 Nickel 0.0073 Titanium 0.013 Vanadium 0.00024 Boron, p.p.rn.

Example Il Following the procedures of Example I, a bituminous coal having identical properties as the coal in Example I and a distillate having an initial boiling temperature (converted to one atmosphere) of about 750 F. were introduced into the solutizer zone to provide a 2 to 1 ratio of solvent to coal. The mixture was agitated while maintaining a pressure of 5 atmospheres and a temperature of 800 F. The resulting coal solution was cooled to a temperature of about 450 IF. and passed through a filter precoated with a standard iter aid. The iiltered coal solution represented a 67.5% recovery of extractable carbonaceous matter based on whole coal and had the fol- The filtered coal solution was heated to 910 F. and coked to provide a coke which was removed from the Coker having the following properties:

Properties:

Volatile matter wt. percent-- V6.5 Sulfur do 0.28 Ash do 0.12 iron do 0.025 Silicon do 0.003 R203 do 0.096 Nickel do 0.0015 Titanium 'do 0.014 Vanad-um do 0.00024 Boron p.p.m 10

rl`he quality of the coke prepared according to the above examples match that of coke prepared from the best petroleum residue.

The overhead from the coker was condensed and had the Ifolio-wing properties:

Properties:

Specific Gravity- -At 10G/60 F. 1.148

At 25/25 C. 1.160 Viscosity at 210 F., centipoises 12.0 Conradson carbon (wt. percent) 0.18 Sulfonation residue None lSulfur (wt. percent) 0.38

Of the coker effluent, about 50% had an initial boiling temperature above 750 F.

While We have shown and'described a preferred form of oui invention, we are aware that variations may be made thereto and we, therefore desire a broad interpretation of our invention within the scope of the disclosure herein 'and the following claims.

We claim:

1. A method of producing substantially ash-free coke and valuable constituents from a de-ashed solution of carbonaceous -matter prepared from a coal selected from the group consisting of bituminous coal, subfbitum-inous coal and lignite in a high lboiling point hydrocarbon solvent of high aromaticity having an initialboiling temperature of above about 750 F. from which solution substantially all suspended mineral matter, fusain and sulfur has been removed which comprises: heating of all said solution to a temperature of from about 850 to 1050 F.; introducing said heated solution in liquid stream into a reaction Zone wherein all of said solution is thermally decomposed into vapor and ash-free, fusainfree and sulfur-free coke; withdrawing as product from said reaction zone said substantially ash-free coke; withdrawing said vapor from said reaction zone and introducing said vapors into a fractionating zone; and fractionating said vapors to obtain a heavy distillate fraction having 9 an initial boiling temperature (converted to one atmosphere) from 650 to 850 F.

2. A method of producinfy substantially ash-free coke and -a valuable constituent from a defashed'solution of carbonaceous matter prepared from a coal selected from the group consisting of bituminous coal, sub-bituminous coal and lignite in a high boiling point hydrocarbon solvent o-f high `aromatici-ty having an initial boiling temperature of above about 750 F. from which solution substantially Vall suspended mineral matter, fusain and sulfur has been removed Iwhich comprises: heating of all said solution to a temperature above its incipient coking tempera-ture; introducing said heated solution in liquid stream into a reaction zone wherein ail of said solution is the mally decomposed into vapors and substantially ashfree, fusain-free and sulfur-free coke; withdrawing as product from said reaction zone said substantially ashfree, fusain-free and sulfur-free coke; withdrawing said vapors from said reaction zone and introducing said vapors into a fractionating zone, and fractionating said vapors to obtain a heavy distillate fraction, having an initial boiling temperature (converted to one atmosphere) of from 650 to 850 F.

3. A method of producing substantially ash-free coke and valuable constituents from a de-asfhed solution of carbonaceous matter prepared from a coal selected from the group consisting of bituminous coal, sub-bituminous coal land lignite in a high boiling point hydrocarbon solvent of high aromaticity having an initial boiling temperature of above about 750 F. from which-solution substantially all suspended mineral matter, fusain and sulfur has been removed which comprises: heating of said solution to a temperature of from about 850 to l050= F.; introducing of all said heated solution in :liquid stream into a reaction zone wherein all of said solution is thermally decomposed into vapors and substantially ash-free, fusain-free and sulfur-free coke; withdrawing as product from said reaction zone said substantially ash-free, fusainfree yand sulfur-free coke; land withdrawing said following constituents from said reaction Zone said vapors.

4. A method of producing substantially ash-free colte and a valuable constituent lfrom a de-ashed solution of carbonaceous mratter prepared from a coal selected from the group consisting of bituminous coal, sub-bituminous coa-l and lignite in a high boiling point hydrocarbon solvent of high aromaticity having an initial boiling temperature of above about 750 F. from which solution substantially kall suspended mineral matter, fusain and sulfur has been removed which comprises: heating of all said solution to a temperature above its incipient coking temperature; introducing; of all said heated solution in liquid stream into reaction zone wherein all of said solution is thermally decomposed into vapors and substantially ash-hee, fusain-free and sulfur-free colte; withdrawing as 10 product from said reaction zone said substantially ashfree, fusain-free and sulfur-free coke; and withdrawing as said valuable constituents from said reaction zone said vapors.

5. A method of producing substantially ash-free colte and valuable constituents trom a de-ashed solution ot carbonaceous matter prepared `from a coal selected from the group consisting of bituminous coal, sub-,bituminous coal `and lignite in a high boiling point hydrocarbon solvent of high Varomaticity having an initial boiling temperature of above about 750 F. from lwhich solution substantially all suspended mineral matter, fusain land sulfur has been removed which comprises: heating of `all said solution to a temperature of from about 850 to 10.50 F.; introducing all of said heated solution in liquid stream into a reaction zone wherein said `solution is thermally decomposed into vapors and substantially `ash-free, fusain- Ifree and sulfur-free coke; withdrawing as product from said reaction zone said substantially ash-free, fusain-free `and sulfur-)Grec coke; withdrawing said vapors lfrom said reaction zone and introducing said vapors into 'a fractionating zone; and fractionating said vapors to obtain a heavy distillate fraction having :an initial. boiling temperature (converted to one atmosphere) above about 750 F.

6. A method of producing substantially ash-free coke and a valuable constituent from a de-ashed solution of carbonaceous matter prepared from `a coal selected yfrom the group consisting of bituminous coal, sub-bituminous coal and lignite in a high boiling point hydrocarbon soflvent of high aromatioity having an initial boiling ternperature of above about 750 F. from which solution substantially all suspended mineral matter, fusain and sulfur has been removed which comprises: heating of all said solution to a temperature above its incipient coking temperature; introducing of all said 'heated solution in liquid stream into a reaction zone wherein all or" said soiution is thermally decomposed into vapors and substantially ash-free, fusain-free yand sulfur-free coke; withdrawing as product from said reaction zone said substantially ashfree, fusain-free and sulfur-free coke; withdrawing said vapors from said reaction and introducing said vapors into a fractionating zone; and fractionating said vapors to obtain a heavy distillate `fraction having an initial boiling `temperature (converted to one atmosphere) above about 750 F.

References Cited in the file of this patent UNITED STATES PATENTS 1,881,927 Pott et al Oct. l1, 1932 2,215,869 Buetesch et al. Sept. 24, 1940 2,221,410 Pier 1 Nov. 12, 1940 2,664,390 Pevere et al Dec. 29, 1953 2,714,086 Bluemner July 26, 1955 .Patent No. 3,109,803

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION November 5, 1963 Ward J. Bloomer et al.

ppears in the above numbered pat- It is hereby certified that error a id Letters Patent should read as ent requiring correction and that the sa Corrected below.

In the sheet of drawing and in the heading to the printed specificati on, title of invention, for "PROCESS FOR PRODUCING SUBSTANTIALLY ASH-FREE BITUMINOUS COAL, SUBBUTUMINOUS COAL AND LIGNITE", each occurrence, read PROCESS FOR PRODUCING SUBSTANTIALLY ASH-FREE COKE FROVI BITUMINOUS COAL, SUBBITUMINOUS COAL AND LIGNITE Signed and sealed this 18th day of August 1964.

(SEAL) mest:

EDWARD J. BRENNER :.:RNEST W. SWIDER Commissioner of Patents nesting Officer

Claims (1)

1. A METHOD OF PRODUCING SUBSTANTIALLY ASH-FREE COKE AND VALUABLE CONSTITUENTS FROM A DE-ASHED SOLUTION OF CARBONACEOUS MATTER PREPARED FROM A COAL SELECTED FROM THE GROUP CONSISTING OF BITUMINOUS COAL, SUB-BITUMINOUS COAL AND LIGNITE IN A HIGH BOILING POINT HYDROCARBON SOLVENT OF HIGH AROMATICITY HAVING AN INITIAL BOILING TEMPERATURE OF ABOVE ABOUT 750*F. FROM WHICH SOLUTION SUBSTANTIALLY ALL SUSPENDED MINERAL MATTER, FUSAIN AND SULFUR HAS BEEN REMOVED WHICH COMPRISES: HEATING OF ALL SAID SOLUTION TO A TEMPERATURE OF FROM ABOUT 850* TO 1050*F.; INTRODUCING SAID HEATED SOLUTION IN LIQUID STREAM INTO A REACTION ZONE WHEREIN ALL OF SAID SOLUTION IS THERMALLY DECOMPOSED INTO VAPOR AND ASH-FREE, FUSAINFREE AND SULFUR-FREE COKE; WITHDRAWING AS PRODUCT FROM SAID REACTION ZONE SAID SUBSTANTIALLY ASH-FREE COKE; WITHDRAWING SAID VAPOR FROM SAID REACTION ZONE AND INTRODUCING SAID VAPORS INTO A FRACTIONATING ZONE; AND FRACTIONATING SAID VAPORS TO OBTAIN A HEAVY DISTILLATE FRACTION HAVING

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