United States Patent: 8882862

Our title doesn't adequately summarize the intent or purpose of the West Virginia University technology related to the conversion of Coal into synthetic liquid petroleum we submit to you herein.

In brief, petroleum refining processes, intended to produce liquid hydrocarbon fuels, center on the function of adding Hydrogen to carbonaceous feed stocks, in order to make hydrocarbons; or, conversely, on removing some Carbon from hydro-carbonaceous feed stocks in order to improve the relative Hydrogen-to-Carbon content, again to make useable hydrocarbons.

That's a coarse and overly-general synopsis, but a serviceable one.

Petroleum refineries do, in many cases, depending to some extent on the quality and nature of the crude natural petroleum being processed, extract Carbon from the petroleum through various processes, in their course of making liquid hydrocarbon fuels, lubricating oils, etc; and, that extracted Carbon exits the refining process in a highly-carbonaceous byproduct called "petroleum coke", aka "pet-coke", or "petcoke". 

Carbonaceous, that is, high-Carbon, "pitch" is, or can be, another intermediate product of Carbon extraction in the refining process.

Petcoke can be of various grades. That is, it can be relatively pure Carbon, or, it can contain relatively high amounts of contaminants. Further, it can be made in, or incidentally exit the refining process in, various physical forms.

Some good background on the subject can be had via:

Petroleum Coke | AFPM; which informs, in part: "Petroleum coke (petcoke) is one of many valued consumer products produced during the oil refining process. Crude oil is processed into gasoline, diesel fuel, jet fuel, lubricating oils and waxes, leaving some residual crude that usually undergoes additional processing.  The crude residue may be further refined by a process known as coking to produce transportation fuels as well as petcoke, which has a variety of uses as an alternative, cost-effective fuel. Coking is not a new technology. The first modern coker in the U.S. was installed in the 1930s. Currently, petcoke is produced at more than 140 refineries around the world. Uses of Petroleum Coke: Petroleum coke is typically used as a source of energy, or as a source of carbon for industrial applications. Fuel grade petcoke represents nearly 80 percent of worldwide production and is a source of fuel for cement kilns and electric power plants. Calcined petcoke has the highest carbon purity and is used to manufacture energy, as well as in the aluminum, graphite electrode, steel, titanium dioxide and other carbon consuming industries"; and:

Petroleum coke - Wikipedia, the free encyclopedia; "Marketable coke is coke that is relatively pure carbon and can be sold for use as fuel (i.e. fuel grade coke), or for the manufacture of dry cells, electrodes, etc. (i.e., anode grade coke). ... Needle coke, also called acicular coke, is a highly crystalline petroleum coke used in the production of electrodes for the steel and aluminum industries and is particularly valuable because the electrodes must be replaced regularly. Needle coke is produced exclusively from either FCC (fluid catalytic cracker) decant oil or coal tar pitch".

The "Fuel grade petcoke" is actually pretty dirty stuff. Many of the metal contaminants in the natural petroleum from which it is derived become concentrated in it. We won't delve too much into that topic, but, the petcoke that arises from the refining of Canada's western province tar sands, for instance, is alarmingly difficult to get rid of because of it's inherently very high content of contaminants; and, accumulations of tar sand pet coke are becoming a critical problem for some American cities, like Detroit and Chicago, where large amounts of it are beginning to accumulate. For background, see: 

Mountain of Petroleum Coke From Oil Sands Rises in Detroit - NYTimes.com; "A Black Mound of Canadian Oil Waste Is Rising Over Detroit"; and:

In Chicago, piles of petroleum coke suggest the future of Canadian tar sands oil | Marketplace.org; "'In Chicago, piles of petroleum coke suggest the future of Canadian tar sands oil'; November 18, 2013; This summer, residents of Chicago’s far southeast side noticed mountains of black dust growing in one corner of the neighborhood. It’s petroleum coke -- pet coke for short. That's what gasoline refineries produce as a byproduct of refining gasoline. It’s full of carbon, sulphur and heavy metals".

Otherwise, as noted in the article, petcoke arising from conventional petroleum sources can be diluted in relatively much cleaner Coal, and then be used as fuel for electric power plants.

But, as also noted, the less contaminated forms of pitch and coke have other uses, as well, as in the making of electrodes for the aluminum refining industry, and, as seen for example in:

Pitch-based carbon fiber - Wikipedia, the free encyclopedia;

the spinning of carbon fibers, a class of product that is finding broader utility, and growing markets, in the manufacture of various high-performance composite materials. 

In any case, as we saw for one example in:

WVU Coal and Carbon-recycling Renewables into Crude Oil | Research & Development | News; concerning, primarily:"United States Patent 8,597,382 - Rubber Material In Coal Liquefaction; December 3, 2013; Inventor: Alfred H. Stiller, Morgantown, WV; Assignee: West Virginia University; Abstract: The present disclosure provides methods and systems for coal liquefaction using a rubber material ... wherein the rubber material is from a rubber tire (and wherein the product) coal extract may be added to a pipeline of petroleum crude for delivery to a petroleum refinery"; and which also contained links to our prior reports concerning: "United States Patent 8,449,632 - Sewage Material in Coal Liquefaction; May 28, 2013; Inventor: Alfred H. Stiller, Morgantown, WV; Assignee: West Virginia University; Abstract: The present disclosure provides methods and systems for coal liquefaction using a sewage material. A method of obtaining a de-ashed coal extract includes exposing a coal to a sewage material. ... The de-ashed coal extract may be added to a pipeline of petroleum crude for delivery to a petroleum refinery"; and: "United States Patent 8,465,561 - Hydrogenated Vegetable Oil in Coal Liquefaction; June 18, 2013; Inventors: Alfred H. Stiller and Elliot B. Kennel, Morgantown, WV; Assignee: West Virginia University; Abstract: The present disclosure provides methods and systems for coal liquefaction using a hydrogenated vegetable oil";

West Virginia University has developed an extensive technology which allows us to incorporate renewable, carbon-recycling wastes and agricultural products in processes which convert our abundant Coal into a form of synthetic petroleum, which "coal extract" WVU specifies can be processed in standard petroleum refineries to produce conventional forms of liquid hydrocarbon fuels and chemicals.

Herein, we see that WVU further posits that some of the excess Carbon in such a hydrogenated liquid "coal extract" can be withdrawn from that liquefied Coal, prior to shipment of the "extract" to a petroleum refinery for processing into fuels. And, the excess Carbon can be processed so that "pitch" and "coke", like that formed by the refining of natural petroleum, can be generated as commercial byproducts, thereby expanding the value of the Coal feedstock and, as WVU reported to the USDOE to be feasible in:

WVU Says Oil From Coal Could Sustain Us For 1,000 Years | Research & Development | News; "'Development of Continuous Solvent Extraction Processes For Coal Derived Carbon Products'; 2009; Elliott Kennel, et. al.; West Virginia University; Sponsoring Organization: US Department of Energy";

thus helping us, in the United States of America, to eliminate any need for us to import any petroleum, at all, from OPEC for at least the next 1,000 years.

Comment follows excerpts from the initial link in this dispatch to the recent:

"Method of Forming a Mesophase Pitch from a Coal Extract Suitable for Processing to a High Value Coke 

Method of forming a mesophase pitch from a coal extract suitable for processing to a high value coke - West Virginia University

Date: November 11, 2014

Inventors: Alfred Stiller, WV, and Peter Stansberry, OH

Assignee: West Virginia University, Morgantown

Abstract: The present disclosure provides methods and systems for coal liquefaction and obtaining a mesophase pitch. A method of obtaining a quinoline insoluble-free and ash-free mesophase pitch may include exposing a coal to a hydrogenated vegetable oil in the presence of a coal-derived solvent to form a slurry, elevating the temperature of the slurry to facilitate liquefying the coal and liberating a volatile matter, separating the insoluble components from the slurry to obtain a de-ashed coal extract that is quinoline insoluble-free, and distilling the coal extract under vacuum to obtain a mesophase pitch with a softening point in the range of 25 degrees Celsius to 160 degrees Celsius, wherein the mesophase pitch can be coked to obtain an anisotropic coke. A quinoline insoluble-free and ash-free pitch may be obtained by the method.

Claims: A method of obtaining a quinoline insoluble-free and ash-free mesophase pitch, comprising: exposing a coal to a hydrogenated vegetable oil in the presence of a coal-derived solvent to form a slurry; elevating the temperature of the slurry to facilitate liquefying the coal and liberating a volatile matter; separating the insoluble components from the slurry to obtain a de-ashed coal extract that is quinoline insoluble-free; and distilling the coal extract under vacuum to obtain a mesophase pitch with a softening point in the range of 25 degrees Celsius to 160 degrees Celsius, wherein the mesophase pitch can be coked to obtain an anisotropic coke.

(With regards to the passage highlighted above, we refer again to our prior reports, as linked-to in our introductory comments, concerning, among others: "United States Patent 8,465,561 - Hydrogenated Vegetable Oil in Coal Liquefaction".) 

The method ... further comprising hydrogenating the coal extract before distilling (and) wherein water liberated as a result of the elevated temperature is captured and stored (and) wherein the volatile matter is condensed and recycled (and) wherein separating comprises at least one of centrifugation, filtration, decanting, and float separation (and) wherein the temperature is elevated to between 300 degrees Celsius and 600 degrees Celsius (and) further comprising agitating the slurry to facilitate liquefying the coal.

The method ... wherein the coal is selected from one or more of a sub-bituminous coal, a bituminous coal, a lignite coal, and an anthracite coal.

The method ... further comprising air blowing the pitch to cross-link the heavier molecules in the pitch and modify the softening point to increase the coke yield (and) wherein the coal-derived solvent comprises at least one of recycled liquefied coal, coal tar distillate, and coal tar pitch.

Background and Field: The present invention relates to coal-to-liquid technology, and specifically to a system and method for liquefying coal using solvents that hydrogenate under mild conditions.

Coal-to-liquid technology refers to chemical processes that convert solid coal into liquid fuels and chemicals.

The hydrogen to carbon ratio (H/C, molar) of coal is about 0.8 while that of liquid fuels is about 2.0. The main functions of the coal-to-liquid processes are breakage of the coal's molecular size and addition of hydrogen into coal, or in other words, destructive hydrogenation of coal. These processes are generally termed as coal liquefaction.

Coal liquefaction may occur by two different pathways: indirect liquefaction and direct liquefaction.

The indirect method converts coal to hydrogen and carbon monoxide, and syngas by reacting coal with steam at high temperatures in an oxygen-starved combustion process.

(For a discussion of the "indirect method" of converting Coal into hydrocarbons, and it's potentials, see our report of:

South Africa Co-produces Power and Hydrocarbons from Coal | Research & Development | News; which centers on: "United States Patent 8,247,462 - Co-production of Power and Hydrocarbons; 2012; Sasol Technology Limited, South Africa; Abstract: A process for co-producing power and hydrocarbons includes in a wet gasification stage, gasifying coal to produce a combustion gas at elevated pressure comprising at least H2 and CO; enriching a first portion of the combustion gas with H2 to produce an H2-enriched gas; and generating power from a second portion of the combustion gas. In a dry gasification stage, coal is gasified to produce a synthesis gas precursor at elevated pressure comprising at least H2 and CO. At least a portion of the H2-enriched gas is mixed with the synthesis gas precursor to provide a synthesis gas for hydrocarbon synthesis, with hydrocarbons being synthesized from the synthesis gas".)

Direct liquefaction includes reaction of coal with hydrogen in a manner that coal becomes liquid. However, direct coal liquefaction has been historically carried out with hydrogen gas, which requires high temperature and pressure. In an example, direct coal liquefaction may involve temperatures in excess of 450 C and 2000 psig pressure.

(For a discussion of "direct coal liquefaction", like the technology developed by West Virginia University, see our report of:

USDOE Demonstrates Economic Feasibility of Coal Liquefaction | Research & Development | News; concerning the USDOE-sponsored study: "Feasibility Of Direct Coal Liquefaction In The Modern Economic Climate; 2009; U.S. Department of Energy; National Energy Technology Laboratory; Pittsburgh, PA; Prepared by: Benjamin G. Oster, et. al.; University of North Dakota, Grand Forks, ND; Abstract: Coal liquefaction provides an alternative to petroleum for the production of liquid hydrocarbon-based fuels. There are two main processes to liquefy coal: direct coal liquefaction (DCL) and indirect coal liquefaction (ICL). This report summarizes historical DCL efforts in the United States, describes the technical challenges facing DCL, overviews Shenhua’s current DCL project in China, provides a DCL conceptual cost estimate based on a literature review, and compares the carbon dioxide emissions from a DCL facility to those from an ICL facility. Shenhua of China is currently bringing a commercial DCL facility online. That facility has estimated a break-even cost of $35–$40 per barrel of oil. ... For comparison, the average cost of petroleum crude oil in 2008 was $93.05 ... . These cost data support the hypothesis that a DCL facility could be competitive with petroleum and profitable. ... An economic comparison (of various Coal conversion technologies, as documented and explained, shows that US Coal can be liquefied at costs from ) $45.94/bbl (of) product (to) $38.35/bbl".) 

Tetralin has been used as a donor solvent. However, a large overpressure of hydrogen and high temperature is needed to transfer the hydrogen from the gas phase to naphthalene, which is produced when tetralin is dehydrogenated as it transfers hydrogen to coal molecules. Thus, in situ re-hydrogenation during liquefaction can be rather costly.

In view of the limitations discussed above, there exists a need for a method of coal liquefaction utilizing an inexpensively produced, effective hydrogen donor solvent to digest coal.

Summary: In an aspect, the present invention provides methods and systems for inexpensively producing an effective solvent to digest coal. Alternatively, the methods and systems may enhance the dissolution ability of heavy aromatic oils by the addition of a hydrogenated liquid. In an embodiment, the hydrogenated liquid may be partially or fully hydrogenated vegetable oil. The present invention may also provide a process that may liquefy coal without the need to hydrogenate the solvent. In embodiments, this may occur by the use of an additive that may contain hydrogen, which may result in de-polymerizing large coal molecules, while also suppressing recombination; thus, resulting in smaller overall molecular distribution and creating a liquid.

In an aspect, a method of obtaining a de-ashed coal extract includes exposing a coal to a hydrogenated vegetable oil in the presence of a coal-derived solvent to form a slurry, elevating the temperature of the slurry to facilitate liquefying the coal and liberating a volatile matter, and separating the insoluble components from the slurry to obtain a de-ashed coal extract, wherein the coal extract is suitable for downstream processing.

The method may further include distilling the coal extract to obtain a pitch. The coal-derived solvent may be selected from a group comprising recycled liquefied coal, coal tar distillate, and coal tar pitch.

The hydrogenated vegetable oil may be at least one of soybean oil, peanut oil, canola oil, olive oil, other vegetable oil or combination of at least two of these oils.

The method may further include heating the insoluble components to liberate a volatile matter and an entrained solvent, blending the insoluble components with a calcareous material and roasting the blend in a kiln at a temperature greater than 1000 degrees Celsius to obtain a clinker, and grinding the clinker to obtain a cement.

(With regards to the immediately-above passage, see our report of:

WVU Makes Cement from Coal-to-Petroleum Residues | Research & Development | News; concerning: "United States Patent 8,512,551 - Forming Cement as a By-Product of Coal Liquefaction; 2013; Inventor: Alfred H. Stiller, Morgantown, WV; Assignee: West Virginia University; Abstract: The present disclosure provides methods and systems for coal liquefaction and obtaining a cement by-product. A method of obtaining a cement by-product of coal liquefaction may include exposing a coal to a hydrogenated vegetable oil in the presence of a coal-derived solvent to form a slurry, elevating the temperature of the slurry to facilitate liquefying the coal and liberating a volatile matter, separating the insoluble components from the slurry, heating the insoluble components to liberate a volatile matter and an entrained solvent, blending the insoluble components with a calcareous material and roasting the blend in a kiln at a temperature greater than 1000 degrees Celsius to obtain a clinker, and grinding the clinker to obtain a cement".)

The method may further include distilling the coal extract under vacuum to obtain a mesophase pitch with a softening point in the range of 25 degrees Celsius to 160 degrees Celsius, wherein the mesophase pitch can be coked to obtain an anisotropic coke. The method may further include coking the pitch to obtain a coke. The coke may be at least one of an anisotropic coke, a metallurgical coke, a graphite coke, an anode coke, and a needle coke. The method may further include air blowing the pitch to crosslink molecules in the pitch, the air blowing of synthetic pitch used for at least modifying a softening point and increasing coke yield.

In an aspect,
a method of obtaining a de-ashed coal extract (which) may be added to a pipeline of petroleum crude for delivery to a petroleum refinery.

In an aspect,
a method of obtaining a de-ashed coal extract may include exposing a coal to a rubber material in the presence of a coal-derived solvent to form a slurry, elevating the temperature of the slurry to facilitate liquefying the coal and liberating a volatile matter, and separating the insoluble components from the slurry to obtain a de-ashed coal extract, wherein the coal extract is suitable for downstream processing. The rubber material may be from a rubber tire.

(Concerning the above, we again refer you to our introductory comments regarding our prior report of: :"United States Patent 8,597,382 - Rubber Material In Coal Liquefaction; December 3, 2013".) 

In an aspect,
a method of obtaining a de-ashed coal extract may include exposing a coal to a sewage material in the presence of a coal-derived solvent to form a slurry, elevating the temperature of the slurry to facilitate liquefying the coal and liberating a volatile matter, and separating the insoluble components from the slurry to obtain a de-ashed coal extract, wherein the coal extract is suitable for downstream processing.

(Refer again to our introductory comments, through which a link can be accessed to our prior report of: "United States Patent 8,449,632 - Sewage Material in Coal Liquefaction; May 28, 2013".) 

In an aspect, a method of obtaining a cement by-product of coal liquefaction may include exposing a coal to a hydrogenated vegetable oil in the presence of a coal-derived solvent to form a slurry, elevating the temperature of the slurry to facilitate liquefying the coal and liberating a volatile matter, separating the insoluble components from the slurry, heating the insoluble components to liberate a volatile matter and an entrained solvent, blending the insoluble components with a calcareous material and roasting the blend in a kiln at a temperature greater than 1000 degrees Celsius to obtain a clinker, and grinding the clinker to obtain a cement.

In an aspect, a method of obtaining a quinoline insoluble-free and ash-free mesophase pitch may include exposing a coal to a hydrogenated vegetable oil in the presence of a coalderived solvent to form a slurry, elevating the temperature of the slurry to facilitate liquefying the coal and liberating a volatile matter, separating the insoluble components from the slurry to obtain a de-ashed coal extract that is quinoline insoluble-free, and distilling the coal extract under vacuum to obtain a mesophase pitch with a softening point in the range of 25 degrees Celsius to 160 degrees Celsius, wherein the mesophase pitch can be coked to obtain an anisotropic coke. A quinoline insoluble-free and ash-free pitch may be obtained by the method.

In an aspect, a method of obtaining a high quality coke from a low rank coal extract may include exposing a coal to a hydrogenated vegetable oil in the presence of a coal-derived solvent to form a slurry, elevating the temperature of the slurry to facilitate liquefying the coal and liberating a volatile matter, separating the insoluble components from the slurry to obtain a de-ashed coal extract that is quinoline insoluble-free, distilling the coal extract under vacuum to obtain a pitch with a suitable softening point, and coking the pitch to obtain a coke. The coke may be at least one of an anisotropic coke, a metallurgical coke, a graphite coke, an anode coke, and a needle coke. The method may further include air blowing the pitch to crosslink molecules in the pitch, the air blowing of synthetic pitch used for at least modifying a softening point and increasing coke yield.

In an aspect, an apparatus for coking includes a coated coking drum that receives a pitch material, wherein the coking drum is coated with a coating comprising at least one of a chromium, an aluminum, a nickel, or an alloy thereof, a heater that heats the pitch material to a coking temperature, and a flash vessel that condenses a liberated volatile matter, wherein a coke formed in the apparatus is readily removable.

In an aspect, a modular coal liquefaction system may include a reactor for exposing a coal to a hydrogenated vegetable oil in the presence of a coal-derived solvent to form a slurry, a heater that elevates the temperature of the slurry in the reactor to facilitate liquefying the coal and liberating a volatile matter, and a centrifuge that separates the insoluble components from the slurry to obtain a de-ashed coal extract, wherein the coal extract is suitable for downstream processing, wherein the reactor, heater, and centrifuge are adapted to be modular. The system may further include a distillation column that distills the de-ashed coal extract to obtain a pitch. The system may further include a coker that cokes at least one of the de-ashed coal extract and the pitch to obtain a coke. The system may be adapted to be modularly disposed on a rail car. The system may be adapted to be modularly disposed on a semi-truck trailer.

In another aspect of the invention, the methods and systems may produce a slurry of coal liquids and undissolved coal particles. The slurry may be further refined to produce a pitch, which may be considered a final product or alternatively may be upgraded to produce lighter hydrocarbon synthetic crude for fuels and chemicals.  

The present disclosure describes a process for coal liquefaction that involves the mixing of ground coal, a coal tar distillate that has been purchased from a coke oven operator or distributor or collected from prior runs of the process, and a hydrogen donor solvent to form a slurry.

Most coal liquefaction was done previously with bituminous coal, but in contrast, the present disclosure describes the advantageous use of sub-bituminous and lignite coals and other low rank coals not previously considered suitable for liquefaction.

It should be understood that the process described herein may be employed with any kind of coal.

Coal liquefaction has previously been carried out with hydrogen gas, requiring high temperature and pressure, commonly at 450 C and 2000 psig pressure. In the Exxon donor process, hydrogenated naphthalene is used as a proton donor. Naphthalene hydrogenation, and in situ re-hydrogenation, requires high temperatures and high pressures. The present disclosure describes the unexpected liquefaction results obtained using hydrogenated vegetable oil or partially hydrogenated vegetable oil in combination with a coal tar distillate (CTD).

Liquefaction can proceed without high temperature or applied pressure that is usually required for liquefaction, however, any level of temperature and pressure may be employed in the process. Also, it is relatively easy and inexpensive to hydrogenate vegetable oil. Coal also liquefies without high temperature or pressure in pipeline crude oil, since pipeline crude has excess hydrogen. Coal also liquefies in CTD mixed with ground up rubber tires as the H-donor, lignin-containing sewage sludge, and other hydrogen donor solvents further described herein.

Although the present disclosure has been described in conjunction with the production of liquid fuels and cokes in a delayed coker, other methods and systems may be possible to carry out the present disclosure without limiting the spirit and scope of the present invention.

The conditions of the process may change with choice of coal to liquefy and desired endpoint.

For example, ... various coals may be liquefied by the process, such as regional coal types, dried coal, pulverized coal, microwaved coal, ground coal, bituminous, subbituminous, anthracite, lignite, brown coal, and the like. Such coals may vary in size, water content, aromatic content, pre-treatment, cleaning, drying, and the like. Thus, certain process changes may be made to accommodate the different coal types, including the kind of hydrogen donor solvent used, amount of hydrogenation of the hydrogen donor solvent, increased hydrogenated material content (etc.). Variables related to the reactor include temperature, agitation, ultrasound, residence time, continuous processing, batch processing, and the like. In the separation process, the speed of separation, duration, and the viscosity of the slurry may all be altered to yield modified tails and/or modified centrate.

(In) the distillation process, any of temperature, pressure, residence time, sparger use, air blowing, and gas flow rate may be varied to modify the distillation output, which can be any of gases, middle distillate, light distillate, pitches (e.g. binder-type pitch, impregnation pitch, graphite pitch, mesophase pitch, other pitches), and the like.

The type of pitch obtained depends on the process variables and the coal extract, such as the kind of coal used to generate the extract, the ash content, the solvents used to liquefy the coal, and the like.

(Coke) yields and types may be varied by changes in pressure, temperature, ramp rate, air blowing, residence time, coating of the coker, type of coke oven used (e.g. delayed coker, fluid coker, Flexicoker, beehive oven, coke battery), and changes in starting pitch material, such as use of the any of the pitches described above ... .

Depending in the input pitch and the process variables, possible coke outputs include graphite coke, needle coke, anode coke, anisotropic coke, isotropic coke, shot coke, sponge coke, calcined coke, catalyst coke, fuel grade coke, and green coke".

---------------------------  

In closing, we note that WVU's process of "Method of Forming a Mesophase Pitch from a Coal Extract Suitable for Processing to a High Value Coke", represents one way of profitably and productively utilizing excess, or residual, carbon that might be left un-reacted in, or is deliberately extracted from, a direct Coal liquefaction process, like that disclosed, for just one example, in WVU's "US Patent 8,449,632 - Sewage Material in Coal Liquefaction".

Such Coal-derived "Pitch", and the technical grades of Coke that can be made from it, might well be cleaner than equivalent products currently derived from the refining of natural petroleum. And, established markets already exist for them.

Other technologies, like that seen for one example in:

Exxon 1997 Coal Liquefaction Residue Steam-Gasification | Research & Development | News; concerning: "United States Patent 4,060,478 - Coal Liquefaction Bottoms Conversion by Gasification;1977; Assignee: Exxon Research and Engineering Company; Abstract: Heavy bottoms produced by the liquefaction of coal ... are converted into more valuable products by ... (after initially producing) gases, hydrocarbon liquids and ...char, thereafter gasifying the char with steam. ... The present invention provides an improved process for the production of liquid and gaseous hydrocarbons from coal ... . This improved process involves the addition of calcium hydroxide ... or a similar alkaline earth metal compound to heavy bottoms produced by the liquefaction of bituminous coal ..., ... pyrolysis of the bottoms product to produce gases, liquids and coke containing the added alkaline earth metal compound, and subsequent gasification of the coke thus produced. The process of the invention is preferably employed in an integrated operation where coal or similar feed material is first liquefied ... with a hydrocarbon solvent ... to produce coal liquids and heavy bottoms. (The) bottoms are pyrolyzed with calcium hydroxide or a similar alkaline earth metal compound to form gases, additional hydrocarbon liquids and coke containing added alkaline earth metal constituents ... .(This) coke is then gasified with steam to form a synthesis gas composed primarily of hydrogen and carbon monoxide, and at least part of the hydrogen generated may be recylced for use in the liquefaction stage of the operation. This sequence of operation has significant advantages over processes suggested in the past and makes possible the production of liquid hydrocarbon products from coal and related materials at lower cost than has generally been possible heretofore";

posit gasifying those still-carbonaceous Direct "Coal Liquefaction Bottoms" so as to make a synthesis gas, or syngas, blend of Carbon Monoxide and Hydrogen, which syngas can then be chemically, catalytically condensed, as for example via the Fischer-Tropsch process, and be made thereby to form more hydrocarbon compounds. Additionally, as indicated by Exxon in their disclosure of the above "United States Patent 4,060,478 - Coal Liquefaction Bottoms Conversion by Gasification", such hydro-gasification of Direct Coal Liquefaction, DCL, residues might yield enough Hydrogen so that some of the Hydrogen, without affecting the utility of the syngas, could be extracted from the synthesis gas product and directed back to the original DCL process, where it would be used to help hydrogenate the Hydrogen-donating solvent employed in the liquefaction and hydrogenation of Coal.

In any case, our excerpts don't do justice to the full Disclosure of this technology for deriving a full range of Carbon and Hydrocarbon products from any grade of Coal.

The West Virginia University scientists even go into considerable detail about how the entire process can be computer-controlled, so as to derive desired slates of products from available grades of Coal - in combination with vegetable oils, waste rubber tires, sewage treatment plant sludge, etc.

And, WVU's entire disclosure of technology for making pitch, and any and all technical and commercial grades of petroleum coke equivalent, out of Coal, is in addition to, and is as a function of, a process that makes, out of Coal, and Coal in combination with certain renewable organic wastes and products of agriculture, in the first place, a "coal extract (which) may be added to a pipeline of petroleum crude for delivery to a petroleum refinery" for refining into conventional liquid "hydrocarbon fuels and chemicals".


West Virginia Coal Association - PO Box 3923 - Charleston, WV 25339 | 304-342-4153 | website developed by brickswithoutstraw