United States Patent: 8083815

Just this past January, we made report of a United States Patent Application, submitted by Shell Oil Company, wherein Coal and Carbon-recycling "waste" materials, along with a stream of Carbon Dioxide gas, in which the solid carbonaceous particles are carried, are all converted into a synthesis gas blend of  Hydrogen and Carbon Monoxide suitable for catalytic chemical condensation into the valuable and versatile alcohol, Methanol, and the substitute Diesel fuel, Dimethyl Ether.

That report is accessible via:

West Virginia Coal Association | Shell Oil Improves Coal-to-Methanol Efficiency with CO2 | Research & Development; and presents details concerning:

"United States Patent Application 20090126259 - Process to Prepare Methanol or Dimethyl Ether; 2009; Inventors: Robert Van Den Berg, et. al., Netherlands; Correspondence Address (and presumed Assignee): Shell Oil Company, Houston, Texas; Abstract: A process to prepare methanol and/or dimethylether from a solid carbonaceous feedstock comprising the steps of (a) feeding an oxygen-comprising gas and the carbonaceous feedstock to a burner firing into a reactor vessel, (b) performing a partial oxidation of the carbonaceous feedstock in said burner to obtain a stream of hot synthesis gas and a liquid slag whereby both the hot synthesis gas and the liquid slag flow downwardly relative to the burner, (c) cooling the hot synthesis gas by direct contact with a liquid water-containing cooling medium, (d) performing a water shift reaction on at least part of the synthesis gas, to obtain a synthesis gas effluent, (e) performing an oxygenate synthesis using the synthesis gas effluent of step (d), to obtain a methanol and/or dimethylether containing oxygenate effluent and a first liquid water-rich by-product,wherein at least part of the first liquid water-rich by-product is used in step (c), forming at least part of the liquid water-containing cooling medium."

As we have previously reported, links to official United States Government electronic files of United States Patent Applications and issued United States Patents too often prove not to be durable; and, when utilized after capture and transmission, connect with other patent documents unrelated to the original subject.

Such, unfortunately, has proven the case with the link to "United States Patent Application 20090126259", as it can be found in the above-referenced report.

Here are two fresh links, to files of the document as it is recorded on different sites, both of which function properly at the time of this transmission:

PROCESS TO PREPARE METHANOL AND/OR DIMETHYLETHER - Den Berg, Robert Van; and:

United States Patent Application: 0090126259.

That said, it may be that those patent application records are, in any case, obsolete; since, herein, we see that an identically-worded United States Patent had been issued to the same team of Shell Oil scientists just weeks before, but had not been published by the time of, our earlier report.

Following, with comment appended, are excerpts from the that relatively recent patent.

But, first, to be clear what this is all about, some advance excerpts seem in order, as in:

"Preferred solid carbonaceous feeds ... are ash and sulphur containing feedstocks, preferably coal, biomass, for example wood, ... and waste"; and:

"More preferably the solid carbonaceous feed is substantially (i.e. >90 wt. %) comprised of naturally occurring coal ... . Suitable coals include lignite, bituminous coal, sub-bituminous coal, anthracite coal, and brown coal"; and:

"The partial oxidation reaction is preferably performed by combustion of a dry mixture of fine particulates of the carbonaceous feed and a carrier gas with oxygen in a suitable burner"; and:

"Examples of suitable carrier gasses to transport the dry and solid feed to the burners are steam, nitrogen, synthesis gas and preferably carbon dioxide. Carbon dioxide is preferred because it achieves a better selectivity to synthesis gas and avoids build-up of nitrogen in downstream gas recycle streams".

Further, as a close read of the full Disclosure seems to confirm, most of that Carbon Dioxide would be supplied by an outside source external to the system itself. Only a relatively small amount of CO2 is specified to exit the system in the product gas, and, there is, in addition to the employment of naturally CO2-recycling "wood" and "waste", along with Coal, in the carbonaceous raw material feed, a net consumption of Carbon Dioxide in this indirect process for the synthesis of liquid hydrocarbon fuels from, principally, Coal.

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

"United States Patent 8,083,815 - Process to Prepare Methanol and/or Dimetylether

Date: December, 2011

Inventors: Robert Van Den Berg, et. al., The Netherlands

Assignee: Shell Oil Company, Texas

Abstract: A process to prepare methanol and/or dimethylether from a solid carbonaceous feedstock comprising the steps of (a) feeding an oxygen-comprising gas and the carbonaceous feedstock to a burner firing into a reactor vessel, (b) performing a partial oxidation of the carbonaceous feedstock in said burner to obtain a stream of hot synthesis gas and a liquid slag whereby both the hot synthesis gas and the liquid slag flow downwardly relative to the burner, (c) cooling the hot synthesis gas by direct contact with a liquid water-containing cooling medium, (d) performing a water shift reaction on at least part of the synthesis gas, to obtain a synthesis gas effluent, (e) performing an oxygenate synthesis using the synthesis gas effluent of step (d), to obtain a methanol and/or dimethylether containing oxygenate effluent and a first liquid water-rich by-product, wherein at least part of the first liquid water-rich by-product is used in step (c), forming at least part of the liquid water-containing cooling medium.

Claims: A process to prepare methanol and/or dimethylether from a solid carbonaceous feedstock comprising the steps of

(a) feeding an oxygen-comprising gas and the carbonaceous feedstock to a burner firing into a reactor vessel,

(b) performing a partial oxidation of the carbonaceous feedstock in said burner to obtain a stream of hot synthesis gas and a liquid slag whereby both the hot synthesis gas and the liquid slag flow downwardly relative to the burner,

(c) cooling the hot synthesis gas by direct contact with a liquid water-containing cooling medium,

(d) performing a water shift reaction on at least part of the synthesis gas, to obtain a synthesis gas effluent,

(e) performing an oxygenate synthesis using the synthesis gas effluent of step (d), to obtain a methanol and/or dimethylether containing oxygenate effluent and a first liquid water-rich by-product, wherein at least part of the first liquid water-rich by-product is used in step (c), forming at least part of the liquid water-containing cooling medium. 

The process ... wherein step (e) comprises the steps of:

(e1) converting at least part of the synthesis gas effluent to a methanol containing effluent and a second liquid water-rich by-product;

(e2) converting at least part of the methanol containing effluent to a dimethylether containing effluent and a third liquid water-rich by-product, wherein the second and third liquid water-rich by-products form part of the first liquid water-rich by-product. 

The process ... wherein step (e2) is performed by converting methanol into dimethylether over a first catalyst, to yield a dimethylether product stream containing methanol, alcohol, dimethylether and water, adding a base to the dimethylether product stream and separating the dimethylether product stream into a vaporous dimethylether-rich stream and a liquid water-containing stream as the third liquid water-rich by-product, which water-containing stream comprises at most 5% wt of methanol, based on the total weight of water and methanol. 

The process ... wherein at least part of the second water-rich by-product is recycled to step (c).

(Even our relatively condensed excerpts, we know, sound complicated. But, in essence, there is a lot internal recycling of water, which might contain some un-recovered product Methanol, going on, with such recycling conducted in such a way that little water seems to be needed from outside the system, especially since some is produced in the hydrocarbon synthesis reactions; and, little of the produced Methanol is lost. What isn't recovered as product is recycled back into the synthesis gas generation stage, to be converted along with Coal and the carrier gas, preferably, as will be seen, Carbon Dioxide, into synthesis gas.)

Background and Field: The present invention relates to improvements relating to a solid carbonaceous feed to a methanol and/or dimethylether process. 

Methanol and dimethylether are useful feedstocks for preparing olefins in so-called oxygenate-to-olefins processes or as feedstock for preparing gasoline in a so-called oxygenate-to-gasoline process.

(Concerning the above, see, for just one instance, our report of:

ExxonMobil Coal to Methanol to Gasoline | Research & Development; concerning, in part: "United States Patent 4,035,430 - Conversion of Methanol to Gasoline; 1977; Mobil Oil Corporation; Abstract: The conversion of methanol to gasoline".)

Such an oxygenate-to-olefins process can convert methanol and/or dimethylether over a catalyst to a product stream that is typically rich in lower olefins, including ethene, propene, as well as butenes, pentenes, hexenes, and also higher olefins and other hydrocarbons and some by-products. The oxygenate feedstock can be obtained from synthesis gas, also referred to as syngas.

Summary: In accordance with the invention there is provided a process to prepare methanol and/or dimethylether from a solid carbonaceous feedstock comprising the steps of 

(a) feeding an oxygen-comprising gas and the carbonaceous feedstock to a burner firing into a reactor vessel, 

(b) performing a partial oxidation of the carbonaceous feedstock in said burner to obtain a stream of hot synthesis gas and a liquid slag whereby both the hot synthesis gas and the liquid slag flow downwardly relative to the burner, 

(c) cooling the hot synthesis gas by direct contact with a liquid water-containing cooling medium, 

(d) performing a water shift reaction on at least part of the synthesis gas, to obtain a synthesis gas effluent, 

(e) performing an oxygenate synthesis using the synthesis gas effluent of step (d), to obtain a methanol and/or dimethylether-containing oxygenate effluent and a first liquid water-rich by-product, 

wherein at least part of the first liquid water-rich by-product is used in step (c), forming at least part of the liquid water-containing cooling medium. 

An advantage of the claimed process is that it is not needed to perform a sophisticated separation of methanol from the liquid water-rich by-product. By recycling these components with the water as cooling medium they can remain in the overall process as such, thereby improving the overall efficiency. Depending on the temperature of the synthesis gas in step (c) part or all of the methanol and/or dimethylether may be converted into hydrogen and carbon monoxide and form part of the synthesis gas. 

Synthesis gas is a gas comprising carbon monoxide (CO), hydrogen (H2) and optionally carbon dioxide (CO2).

A particularly interesting source of synthesis gas is from the gasification of a solid carbonaceous feedstock such as coal.

Preferred solid carbonaceous feeds as used in step (a) are ash and sulphur containing feedstocks, preferably coal, biomass, for example wood, in particular torrefied wood, and waste (and) most preferably coal.

Suitable coals include lignite, bituminous coal, sub-bituminous coal, anthracite coal, and brown coal. 

The gasification is preferably carried out in the presence of oxygen-comprising gas and optionally some steam, the purity of the oxygen-comprising gas (and, substantially) pure oxygen is preferred ... .

The ratio between oxygen and steam is preferably from 0 to 0.3 parts by volume of steam per part by volume of oxygen.

The partial oxidation reaction is preferably performed by combustion of a dry mixture of fine particulates of the carbonaceous feed and a carrier gas with oxygen in a suitable burner.

Examples of suitable carrier gasses to transport the dry and solid feed to the burners are steam, nitrogen, synthesis gas and preferably carbon dioxide.

Carbon dioxide is preferred because it achieves a better selectivity to synthesis gas and avoids build-up of nitrogen in downstream gas recycle streams.

Hydrogen is preferably prepared from part of a CO depleted stream, more preferably from the first CO depleted stream. Hydrogen is preferably prepared in a Pressure Swing Adsorption (PSA) unit, a membrane separation unit or combinations of these. The hydrogen manufactured in this way can then be used as the hydrogen source in a possible further hydroprocessing step wherein the hydrocarbon products as made in step (e) are used as feed. This arrangement reduces or even eliminates the need for a separate source of hydrogen, e.g. from an external supply, which is otherwise commonly used where available.

(Unfortunately, some of the internal Hydrogen preparation methods described in the full Disclosure also result in the co-production of some additional Carbon Dioxide, which could be recycled to the synthesis gas generation phase, but, which practice would limit the amount of CO2 which could be imported from outside the system as a "carrier gas" for the "carbonaceous feedstock". We would suggest, instead, that a process such as that seen in our report of:

USDOE Algae Make Hydrogen for Coal and CO2 Hydrogenation | Research & Development; concerning: "United States Patent 4,442,211 - Method for Producing Hydrogen and Oxygen by Use of Algae; 1984; Assignee: The United States of America; Abstract: Efficiency of process for producing H2 by subjecting algae in an aqueous phase to light irradiation is increased by culturing algae which has been bleached during a first period of irradiation in a culture medium in an aerobic atmosphere until it has regained color and then subjecting this algae to a second period of irradiation wherein hydrogen is produced at an enhanced rate. Claims:A method of producing H2 and O2 by use of algae and light";

wherein certain strains of Algae, cultivated and fed, among other things, even more Carbon Dioxide recovered from whatever handy source, can be made to, in alternating cycles, produce both, as above, any needed extra "hydrogen ... from an external supply" and the "oxygen-comprising gas" needed to effect "a partial oxidation of the carbonaceous feedstock", as specified above. )


The simple ability to change the degree of division into the sub-streams also provides a simple but effective means of accommodating variation in the H.2/CO ratio in the gaseous stream as obtained in step (c) which variations are primarily due to variation in feedstock quality. With feedstock quality is here meant especially the hydrogen and carbon content of the original carbonaceous feedstock, for example, the `grade` of coal. Certain grades of coal generally having a higher carbon content will, after gasification of the coal, provide a greater production of carbon monoxide, and thus a lower H2/CO ratio.

The ability to change the degree of division of the synthesis gas stream into the sub-streams allows the process to use a variety of feedstocks, especially `raw` coal, without any significant re-engineering of the process or equipment to accommodate expected or unexpected variation in such coals. 

Suitably the synthesis gas is subjected to a CO2 recovery system thereby obtaining a CO2 rich stream and (which) CO2 rich stream may be used as the CO2 containing transport gas.

(Shell does indicate that some CO2 in excess of what can be efficiently utilized in the gasification step might be produced; and, they suggest nonsense like geologic sequestration to prevent emission. We suggest, instead, the CO2-recycling, Hydrogen and Oxygen producing, process of "US Patent 4,442,211 - Method for Producing Hydrogen and Oxygen by Use of Algae", as cited above, or, for just one out of now many similar alternatives, the process disclosed in our report of:

USDOE Converts CO2 to Gasoline | Research & Development; concerning our own USDOE's: "United States Patent 4,197,421 - Synthetic Carbonaceous Fuels and Feedstocks; 1980; Assignee: The United States of America; Abstract: This invention relates to the use of a three compartment electrolytic cell in the production of synthetic carbonaceous fuels and chemical feedstocks such as gasoline, methane and methanol by electrolyzing an aqueous sodium carbonate/bicarbonate solution, obtained from scrubbing atmospheric carbon dioxide with an aqueous sodium hydroxide solution, whereby the hydrogen generated at the cathode and the carbon dioxide liberated in the center compartment are combined thermocatalytically into methanol and gasoline blends";

wherein any excess Carbon Dioxide liberated by the process of our subject, "US Patent 8,083,815 - Process to Prepare Methanol and/or Dimetylether", wherein Coal, Carbon-recycling wastes and even Carbon Dioxide itself are consumed in an initial gasification, could itself be efficiently converted "into" not only more "methanol", but, "gasoline blends", as well.)

The CO2 recovery system is preferably a combined carbon dioxide/hydrogen sulfide removal system, preferably wherein the removal system uses a physical solvent process. 

(When) the syngas contains CO2, water is produced as by-product in the methanol-containing effluent, which is suitably separated. According to the present invention, this separation does not need to be conducted to achieve high water purity, since residual methanol in the separated water can advantageously be recycled to step (c) of the process. The water is also referred to as third liquid water-rich by-product in the present description and claims.

(It's important to note that the only real reason they are separating Carbon Dioxide from the synthesis gas product is to reduce the loss of available Hydrogen through reactions with the Carbon Dioxide, which leads to the co-production of Water, H2O. If enough economical Hydrogen were available, and economical means of distilling or otherwise separating Methanol and co-product Water were available, there would be no need to worry about separating the Carbon Dioxide in the first place, since it would all be consumed in the production of the Methanol and H2O, as explained to a certain extent in passages following.)

Carbon dioxide is optionally present in an amount of not greater than 50% by weight, based on total weight of the syngas.

Also as stated there, the stoichiometric molar ratio is sufficiently high so as maintain a high yield of methanol, but not so high as to reduce the volume productivity of methanol. Preferably, the syngas fed to the methanol synthesis has a stoichiometric molar ratio (i.e., a molar ratio of H2:(2CO+3CO2)) of from about 1.0:1 to about 2.7:1, more preferably from about 1.1 to about 2.0, more preferably a stoichiometric molar ratio of from about 1.2:1 to about 1.8:1. 

The syngas can contain CO2 and CO at a molar ratio of from about 0.5 to about 1.2, preferably from about 0.6 to about 1.0.

(It is, in other words, perfectly acceptable to utilize herein a  synthesis gas that contains just as much Carbon Dioxide as it does Carbon Monoxide. There is no need, at all, for this process to emit Carbon Dioxide; and, it can, as we've attempted to illuminate, actually consume some arising from sources external to the process.)

Dimethylether can be produced directly from syngas; or in a two-step process from methanol first produced from syngas, or from methanol and syngas together. Along all routes, a water-containing by-product is produced which can be recycled (in the system of) the present invention, wherein it is acceptable that methanol and/or dimethylether are contained in the recycle stream. 

The invention is also directed to a process to prepare an olefin-containing product or a gasoline product from a solid carbonaceous feedstock by performing the process as described above to obtain a methanol- and/or dimethylether-containing oxygenate effluent and converting the oxygenate effluent to an olefin-containing product or a gasoline product and a fourth liquid water-rich by-product ... .

Processes to convert an oxygenate effluent to a gasoline type product are well known. A known example is the ExxonMobil Methanol to Gasoline (MTG) Process."

------------------------

And, since Shell Oil, in closing, specifies their collegial competitor's "Methanol to Gasoline (MTG) Process", we refer you, for more information on that, to our report of:

ExxonMobil "Clean Gasoline from Coal" | Research & Development; concerning the ExxonMobil marketing brochure entitled: "Methanol to Gasoline (MTG): Production of Clean Gasoline from Coal; So Advanced, Yet So Simple".

As herein, according to Shell Oil, and as affirmed by our expert US Government patent examiners, we can convert our abundant Coal, some of our CO2-recycling renewable "biomass, ... wood, ... and waste", and, even, Carbon Dioxide itself, into Methanol. As further explained by Shell Oil, that Methanol, in their own system, can be further processed in the production of more of the substitute Diesel fuel, Dimethyl Ether; or, it can be forwarded into "the ExxonMobil Methanol to Gasoline (MTG) Process", for an obvious purpose.

ExxonMobil, as in our above citation, describes the "Production of Clean Gasoline from Coal" as "Simple".

Y'know, what ain't simple, at all, to us here, is why none of these options, none of them, are being publicly revealed to the people who most deserve to know of them:

The OPEC-extorted, Cap & Trade-threatened and underemployed citizens of United States Coal Country.

As herein, Shell Oil and, by reference, ExxonMobil, have fully and openly explained how our abundant domestic Coal and our some say too-abundant Carbon Dioxide, and the renewable products of our own fields and forests, can be converted into any, quite literally any, of the liquid hydrocarbon fuels we now fight foreign wars and mortgage our children's future to OPEC in order to keep ourselves supplied with.

It's far, far past time the news of all of that did get out.

Strangely, Big Oil, and our Big Government, have done their parts; more, really, than could logically have been expected of them.

Maybe our Coal Country public media should start doing their parts, as well; what, one might be compelled to think, could rightfully be expected of them.


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