We have documented many times that processes for the hydro-gasification of Coal, wherein Steam is employed as one of the agents of gasification, so as to increase the Hydrogen content of the resulting hydrocarbon Synthesis Gas, can be made so efficient that the entire solid Carbon content of the Coal is consumed in the gasification process.
There are no carbonaceous residues remaining which must somehow be disposed of.
Only inert ash remains; an ash that sounds very much like Coal-fired power plant fly ash, and which, thus, as in, for just one example, our earlier report:
Scientists Convert Coal Ash to Cement | Research & Development; concerning: "New Use for Coal Ash: Material Provides Strong and Lightweight Alternative to Concrete – without Cement; Each year, coal-burning power plants, steel factories and similar facilities in the United States produce more than 125 million tons of waste, much of it fly ash and bottom ash left over from combustion. An assistant professor in Georgia Tech’s School of Civil and Environmental Engineering, Mulalo Doyoyo, has developed a new structural material based on these leftovers from coal burning. Known as Cenocell (TM), the material offers attributes that include high strength and light weight – without the use of cement, an essential ingredient of conventional concrete";
has the potential for further commercial employment, through recycling into a cement replacement, or cement extender, for use in "conventional concrete" applications.
Furthermore, we have also documented the fact that Carbon Dioxide, as well, can be used as an agent of Coal gasification, and be thereby converted, through reaction with the Coal, into the Carbon Monoxide component of such hydrocarbon Syngas.
So effective is the reaction between CO2 and hot Coal, in fact, that, again as we have documented, Carbon Dioxide, recovered from a source outside the Coal gasification process itself, can be imported into the system for conversion into the reactive Carbon Monoxide.
Such, perhaps, might not be quite the case in the German Coal gasification technology we report herein.
Those CO2-utilization principles are, however, employed to ensure that the entire Carbon content of the Coal is consumed, while virtually no Carbon Dioxide is co-produced, in an efficient Coal hydro-gasification process designed to generate, primarily, a refined blend of Carbon Monoxide and Hydrogen suitable for hydrocarbon synthesis.
Comment follows excerpts from:
"United States Patent 4,347,064 - Process of Gasifying Fine-Grained Solid Fuels
Date: August, 1982
Inventors: Lothar Rey, et. al., Germany
Assignee: Metallgesellschaft AG, Frankfurt am Main
Abstract: A process of gasifying fine-grained solid fuels for the production of a product gas that contains hydrogen, carbon oxides and methane comprises a treatment with steam, oxygen and/or carbon dioxide in two interconnected gasifying stages ... . In the first gasifying stage, the fuel is gasified in a circulating fluidized bed ... . The residual solids which become available in the first gasifying stage are fed to the second gasifying stage and are virtually completely gasified therein, except for residual ash, by a treatment with a gasifying agent which includes oxygen. At least one-half of the product gas from the second gasifying stage is fed to the first gasifying stage and used as fluidizing fluid therein.
Claims: In a process of gasifying fine-grained solid fuels to produce a product gas which contains hydrogen, carbon oxides and methane in two interconnected gasifying stages by treatment with at least one of the gasifying agents of the group consisting of steam, oxygen and carbon dioxide, the gasifying stage containing a first reactor and a first separation zone (wherein) fresh fine-grained solid fuel is ... partially gasified ... and product gas is withdrawn from said first separation zone, ... solids are separated from said product gas and said separated solids are divided into two partial streams, a first partial stream of which is recycled into the first gasifying stage and the second partial stream of solids is fed into the second gasifying stage, said second gasifying stage containing a second reactor and a second separation zone, ... in said second separation zone solids are separated from the hot gas produced in said second gasifying stage, feeding gasifying agent into the reactor of the first gasifying stage which consists mainly of steam and contains less oxygen than the gasifying agent fed into the second gasifying stage; and maintaining a temperature in the second gasifying stage which is higher than the temperature maintained in the first gasifying stage ... .
A process ... wherein product gas from the first or second fluidized bed stages is purified to remove CO2, and the so separated CO2 is employed as a gasifying agent for (the) fuel ... .
A process ... wherein the product gas is used ... as a synthesis gas.
Background and Field: This invention relates to a process of gasifying fine-grained solid fuels to produce a product gas which contains hydrogen, carbon oxides, and methane, in two interconnected gasifying stages by a treatment with at least one of the gasifying agents consisting of steam, oxygen and carbon dioxide.
Solid fuels which may be used in the process include particularly coal ... .
At the relatively high gasifying temperatures, carbon dioxide acts also as an oxidizing gasifying agent.
(Product) gas from the second stage (transfers) heat to the first stage so that the gasifying agents fed to the first stage may consist of steam and ... CO2 but may contain only little or no oxygen.
(Note: There is no need for "oxygen", whether supplied by air, with the attendant risk of forming unwanted oxides of Nitrogen, or, as purified Oxygen separated from air, with the attendant extra expense.)
In general, ... the product gas obtained by the gasification according to the invention ... will have to be subjected to various conditioning treatments before it can be put to the desired use. It will be useful mainly as a starting material for the production of synthesis gases and fuel gases and for that purpose may be subjected to a thermal or catalytic aftertreatment. For instance, it may be cracked to convert (any remaining) hydrocarbons in the product gas to CO and H2 as (additional) synthesis gas components.
(Or) the product gas may be hydrocracked to convert ... its condensible hydrocarbons to methane.
(And, the remaining product) gas may be ... (further) converted in known manner to ... methanol."
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So, in the end, virtually the entire Carbon content of Coal can, ultimately, through processes following, and using the products of, United States Patent 4,347,064, be converted into "methane" and/or "methanol".
And, we remind you, that, as in:
Standard Oil 1950 CO2 + CH4 + H2O = Syngas | Research & Development; concerning: "United States Patent 2,522, 468 - Production of Synthesis Gas; 1950; Assignee: Standard Oil; Abstract: My invention relates to the production of a mixture of carbon monoxide and hydrogen suitably proportioned for use as a feed-gas in the synthesis of hydrocarbons ... including those boiling in the gasoline and gas oil range (from) a mixture of methane, steam and carbon dioxide";
Methane can - - once we have it, made, as herein, from the raw materials provided by the process of United States Patent 4,347,064, from Steam, Coal and Carbon Dioxide - - be reacted with even more Carbon Dioxide, recovered from whatever source, perhaps a Corn Ethanol fermentation and distillation facility, and be made thereby to form a gas mixture suitable for "the synthesis of ... gasoline".
Furthermore, as seen in:
ExxonMobil Coal to Methanol to Gasoline | Research & Development; which concerns: "United States Patent 4,035,430 - Conversion of Methanol to Gasoline; 1977; Assignee: Mobil Oil Corporation, NY; Abstract: The conversion of methanol to gasoline";
Methanol can - - once we have it, too, made, as herein, from the raw materials provided by the process of United States Patent 4,347,064, from Steam, Coal and Carbon Dioxide - - be further converted "to gasoline".
And, since we cite ExxonMobil, we'll take the opportunity to remind you that they, as well, have a process very similar in theme to that of USP 4,347,064, as seen in our earlier report:
Exxon 1976 Coal to Methanol + Methane | Research & Development; concerning: "United States Patent 3,993,457 - Concurrent Production of Methanol and Synthetic Natural Gas; 1976; Assignee: Exxon Research and Engineering Company, NJ; Abstract: Methanol and synthetic natural gas are produced concurrently by introducing a carbonaceous material into a gasification zone, and thereafter, passing sequentially the synthesis gas thus formed through a ... methanol synthesis zone and a methanation zone.
Claims: An integrated process for the production of methanol and a synthetic natural gas, which is substantially methane, from a carbonaceous material".