We have, among other issues, been regularly extolling the many virtues of Methane, which include that it can be directly catalyzed into liquid hydrocarbons; that it can enhance the productivity of some processes of indirect Coal conversion into liquid hydrocarbons; and, that it can be reacted with Carbon Dioxide, to recycle that supposed greenhouse pollutant, in reforming reactions, which, we have just recently discovered, and will document, have been known of for a surprisingly long time, to synthesize even more liquid hydrocarbons.
We have documented, and will further report, that such valuable Methane can be synthetically manufactured via both the Sabatier recycling of Carbon Dioxide and the steam-, or hydro-, gasification of Coal.
Herein, we submit further documentation of that last fact.
The invention described by Texaco in this US Patent isn't so much about how to convert a variety of carbonaceous materials, including Coal, into Methane, but, about how to do it better and more efficiently, by reducing Carbon buildup on the catalyst, a frequently-noted concern in similar and related technologies.
Moreover, as with many petroleum industry processes related to the conversion of Coal into more versatile hydrocarbons, you have to dig pretty deep to discover that it is, in fact, among a few other things, Coal that is the primary focus of this process.
From this Patent's full "Description" segment, we submit the following excerpt as a foreword:
"Hydrocarbonaceous fuels that are suitable feedstocks to the gas generator include (among the other things) asphalt, coal tar, coal oil, ... . Included also are pumpable slurries of solid hydrocarbonaceous fuels e.g. coal, coal char, particulate carbon, and petroleum coke in a liquid hydrocarbon fuel such as one previously listed, or in water."
Note that "coal oil" is specified to be a "liquid hydrocarbon fuel" in which Coal can be suitably slurried for use in this process, as in others similar which we have previously reported.
Summary comment follows additional excerpts from:
"United States Patent 3,922,148 - Production of a Methane-rich Gas
Date: November, 1975
Inventor: Edward Child, NY
Assignee: Texaco Development Corporation, NY
Abstract: This is an improved continuous process for producing a clean methane-rich gas stream without the concomitant formation of particulate carbon which would ordinarily decrease the efficiency of the process and shorten the life of the catalyst. By-product superheated steam is simultaneously produced at a maximum temperature. The product stream may have a methane content up to 98 to 99 mole percent or higher and a gross heating value up to 1000 BTU per SCF or more. Process steps include partial oxidation of a hydrocarbonaceous fuel under operating conditions that produce a synthesis gas ... and reacting the methane-rich process gas stream in one to three catalytic methanation stages under critical operating conditions that increase the methane content in the process gas stream stepwise up to 98 mole percent or higher without incipient soot formation ... . Heat from the highly exothermic methanation reaction is used to make valuable by-product superheated steam. The product gas may be burned without polluting the atmosphere.
This invention relates to a continuous process for the production of a clean methane rich gas stream from hydrocarbonaceous fuels. More specifically, the present invention relates to the production of gaseous heating fuels free from particulate carbon. ... the particulate carbon may be removed by scrubbing the process gas with a scrubbing fluid comprising oil, water, or both. The slurry of particulate carbon and scrubbing fluid may be recycled to the gas generator as a portion of the hydrocarbonaceous feedstock."
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We conclude by reminding you that Texaco had developed an extensive portfolio of Carbon gasification technologies, prior to their ultimate assimilation by Chevron, in addition to that disclosed herein, which they proposed, as we've documented, to apply to a variety of carbonaceous, Carbon-recycling feed stocks, in addition to Coal.
More on those Texaco gasification technologies is to follow. But, for now, again, it seems clear:
If we do want Methane, for whatever good purpose, we can make it from Coal.
