Production of gases from carbonaceous solids
More than one half of a century ago, the United States Petroleum Industry and, by extension, through approval and issuance of the United States Patent we enclose in this dispatch, our United States Government, knew full well, that: not only could Coal be converted, through gasification and subsequent catalytic condensation, into liquid hydrocarbon fuels, but, through inclusion in the gasification process, so could Carbon-recycling botanical products and, even, Carbon Dioxide itself.
Such a concept shouldn't be unfamiliar to you, assuming you to have followed our posts thus far.
Examples of our reportage concerning such potentials have included, for just two examples:
More Oklahoma CO2 + Coal = Hydrocarbon Syngas | Research & Development | News; concerning: United States Patent 4.040,976 - Process of Treating Carbonaceous Material with Carbon Dioxide; 1977; Assignee: Cities Service Company, OK; Abstract: A mixture of carbon dioxide and a carbonaceous material, such as coal, is rapidly heated in a reactor, giving a gaseous effluent comprising carbon monoxide"; and:
Conoco 2011 Coal + CO2 + H2O + O2 = Syngas | Research & Development; concerning: "United States Patent 7,959,829 - Gasification System and Process; 2011; Assignee: ConocoPhillips Company, Houston; Abstract: A system and process for gasifying carbonaceous feedstock with staged slurry addition (wherein) Claims: A process for gasification of a carbonaceous material (wherein) particulate carbonaceous material (is partially combusted) with ... oxygen-containing gas, steam, and mixtures thereof, thereby evolving heat and forming ... synthesis gas and molten slag (and) wherein said carrier liquid (for the carbonaceous material) is selected from group consisting of water, liquid Carbon Dioxide, (or) mixtures thereof".
And, although Coal is mentioned most often in such technologies, as a specific "carbonaceous material", others, as for one example in:
Exxon Co-Gasifies Coal and Carbon-Recycling Biomass | Research & Development; concerning: "US Patent Application 20100083575 - Co-gasification Process for Hydrocarbon Solids and Biomass; 2010; Assignee: ExxonMobil Research and Engineering Company; Abstract: A process for the co-gasification of carbonaceous solids (coal) and biomass (wherein) the solid carbonaceous particles comprise coal (and/or) coke derived from coal (and) wherein the biomass comprises biological matter selected from wood, plant matter, municipal waste, green waste, byproducts of farming or food processing waste, sewage sludge, black liquor from wood pulp, and algae";
do identify a whole catalog of other, renewable and Carbon-recycling, "
ExxonMobil's specification of "algae" as a suitable co-feed, with Coal, in a Carbon conversion process, is especially meaningful, we think, in light of technology such as that seen to have been developed by our own USDOE, as, for just one example, seen in our report of:
USDOE Algae Recycle CO2 into Liquid Fuels | Research & Development; concerning: "Liquid Fuels from Microalgae; 1987; USDOE; Abstract: The ... technology to produce gasoline and diesel fuels from microalgae. A technical and economic analysis, "Fuels from Microalgae," demonstrates that liquid fuels can be produced from mass-cultured microalgae at prices that will be competitive with those of conventional fuels by the year 2010."
Wherein it's disclosed how Algae cultures can be "fed" with CO2-laden industrial exhaust gases, and be made to produce "lipids", what we are compelled to characterize as botanically-produced crude petroleum, which can then be refined by fairly conventional means into "gasoline and diesel". The USDOE proposes that, after lipid extraction, the cellular residue of the Algae could be gasified, in a process similar to that of ExxonMobil's ""US Patent Application 20100083575" we suggest, perhaps thus along with Coal, to produce a blend of Carbon Monoxide and Hydrogen synthesis gas suitable for catalytic condensation, via any one of several long-known and established processes, into even more liquid hydrocarbons.
Herein, we learn that the basics of such potentials, wherein both Coal and Carbon-recycling botanical materials could be converted into a hydrocarbon synthesis gas through gasification reactions with a number of gases, including Carbon Dioxide itself, were obvious, even more than half of a century ago, both to the one-time flag bearer of the American petroleum industry, and, to our own United States Government.
Comment follows excerpts from the initial link in this dispatch to:
"United States Patent 2,644,745 - Production of Gases from Carbonaceous Solids
Date: July, 1953
Inventor: Charles Hemminger, NJ
Assignee: Standard Oil Development Company, DE
Abstract: The present invention relates to the conversion of carbonaceous solids into combustible gases.
More specifically, the invention is concerned with the gasification of all types of coal (and) cellulosic materials ... to produce ... gas mixtures containing CO and H2 suitable for the catalytic synthesis of hydrocarbon and oxygenated compounds.
(First, "oxygenated compounds" would include alcohols, such as Methanol.
Second, "cellulosic materials" would include any kind of fibrous plant matter, including the cellular debris of CO2-recycling Algae, as in the USDOE technology cited in our opening comments, after the bio-lipids had been extracted for conversion into "gasoline and diesel fuels"; and, other various materials such as crop wastes and sawdust, and, previously-loved Coal Country news rags.
Finally, do not miss the implications, the import, of the immediately-following excerpted passage.)
Heretofore, solid fuel materials such as ... coal ... have been converted with steam (and) CO2 ... into more valuable gaseous fuels and gas mixtures suitable for chemical synthesis mainly by fixed bed processes.
(Again, do not miss that point: By 1953, there were already established methods, methods that had been practiced "Heretofore", whereby Coal could be gasified with Steam and Carbon Dioxide, and be thereby converted into "valuable ... gas mixtures suitable for" the "chemical synthesis" of hydrocarbons.)
It is ... the principal object of my invention to provide improved means for the continuous production of combustible gases from carbonaceous solids.
Another object of my invention is to provide an improved process for the continuous gasification of carbonaceous solids ... and with full utilization of available carbon.
(Another) object ... is to provide an improved process for the continuous conversion of ... carbonaceous solids into gas mixtures containing H2 and CO, suitable for the catalytic synthesis of hydrocarbons and oxygenated organic compounds (i.e., Alcohols), at optimum gasification rates, full utilization of available carbon in the gasification process and convenient disposal of non-carbonaceous solid gasification residue.
In (the present invention) carbonaceous solids are gasified ... while suspended in ... steam and/or CO2.
(Heat) required to support the endothermic gasification reaction (is) generated by a partial combustion of the carbonaceous charge with free oxygen.
(The "oxidation" is controlled so as to be "partial", so that more Carbon Monoxide is generated and the production of Carbon Dioxide is minimized, although any CO2 that is produced can be, through the process of the invention itself, reduced back into Carbon Monoxide through further reaction with hot Carbon. The "free oxygen" specified could be as it is contained in air; but, to minimize co-production of unwanted Nitrogen Oxides, it could be a relatively pure Oxygen, as would be emitted by green Algae, as in the above-cited USDOE's "Liquid Fuels From Microalgae", as they went about their photosynthetic business of converting industrial effluent CO2 into the bio-lipid raw materials for "gasoline and diesel fuels".)
(The described) process permits continuous and complete conversion of available carbon into heat and product gas and the withdrawal of substantially carbon free ash.
(Such "carbon-free ash" can be an important by-product. For instance, as seen in:
Virginia Converts Coal Ash to Cash | Research & Development; concerning: ""Dominion Recycling Center Turns Ash to Cash; 2006; (A) Dominion Virginia Power ... facility ... acts like a big oven. It bakes black, carbon-laden fly ash into a kinder, gentler and paler byproduct that can be sold and made into concrete, roof tiling and construction blocks, among other alternative uses"
although typical Coal ash can be recycled and utilized to great benefit in various "concrete" applications, if it contains residual Carbon, that Carbon needs to be cooked out of it before it can be so used. The Coal ash produced by the Coal conversion process of our subject, "United States Patent 2,644,745", would not, since it is "substantially carbon free", require the extra expense of heat treatment before it could be used in the profitable manufacture of "concrete, roof tiling and construction blocks, among other" things.)
The absolute and relative amounts of oxygen, steam and/or CO2 are so chosen that complete conversion of the carbon ... to gaseous products ... takes place at a temperature above the fusion point of the ash ... .
(The above, so that the ash more readily "melts" out of the reactant mass. There is a tradeoff there between effecting more complete combustion, by adjusting the "relative amounts of oxygen, steam and/or CO2" with which the Coal is gasified, so that the temperature is high enough to melt the ash, but with the resultant generation, or actually what we would call the "pass through", of more Carbon Dioxide that would then have to be collected and recycled back to the gasification chamber, and, restricting combustion so that relatively less Carbon Dioxide is passed through, but with the temperature being thus reduced, since the C+CO2=2CO reaction is endothermic, resulting in a lower temperature of reaction and, perhaps, a less complete ash fusion and removal.)
The product gas ... is withdrawn (and) rapidly cooled ... in a waste heat boiler wherein steam required for the process may be produced.
(We've many time documented similar but separate opportunities for recycling heat in various Coal conversion processes. In essence, heat energy generated by some exothermic chemical reaction steps in the total process can be collected, and directed to other, needed, endothermic reactions, thus providing a greater economy in the production of the Coal syngas.)
Claims: (The) process of converting solid carbonaceous ash-containing materials into gases containing carbon monoxide (through reaction with) a gaseous medium containing oxygen in admixture with ... steam, carbon dioxide and mixtures thereof."
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We do note that analyses of product gases provided by Standard Oil, but not reproduced in our excerpts, do show that the final product gas does contain a minor percentage of Carbon Dioxide; but, even that minor percentage is higher than that already present in the Earth's atmosphere.
We submit that Carbon Dioxide, too, could be separated and recycled back to the initial Coal gasification, as a part of the CO2 with which the Coal is initially gasified. Otherwise, it could be collected and sent to a process such as that described in the above-referenced USDOE study, "Liquid Fuels from Microalgae", for conversion into the raw materials from which we can make "gasoline and diesel fuels".
Otherwise, the minor amount of Carbon Dioxide that is emitted in the final product could, and should, be more than offset both by the inclusion of naturally CO2-recycling "cellulosic materials", as specified herein by Standard Oil, to be gasified with Coal, and, by the CO2, recovered from whatever source, with which the Coal and the CO2-recycling "cellulosic materials" are to be gasified, as again specified herein by Standard Oil, as in: "while suspended in ... steam and/or CO2"; and, through such gasification to be thereby converted into "mixtures (of) CO and H2 suitable for the catalytic synthesis of hydrocarbon ... compounds".