The enclosed, fairly recent, US CoalTL patent is interesting for several reasons.
Additional comment follows the excerpt:
"Direct coal liquefaction process
United States Patent 5256278
Abstract:
An improved multistep liquefaction process for organic carbonaceous matter which produces a virtually completely solvent-soluble carbonaceous liquid product. The solubilized product may be more amenable to further processing than liquid products produced by current methods. In the initial processing step, the finely divided organic carbonaceous material is treated with a hydrocarbonaceous pasting solvent containing from 10% and 100% by weight process-derived phenolic species at a temperature within the range of 300° C. to 400° C. for typically from 2 minutes to 120 minutes in the presence of a carbon monoxide reductant and an optional hydrogen sulfide reaction promoter in an amount ranging from 0 to 10% by weight of the moisture- and ash-free organic carbonaceous material fed to the system. As a result, hydrogen is generated via the water/gas shift reaction at a rate necessary to prevent condensation reactions. In a second step, the reaction product of the first step is hydrogenated.
Inventors:
Rindt, John R. (Grand Forks, ND)
Hetland, Melanie D. (Grand Forks, ND)
Hetland, Melanie D. (Grand Forks, ND)
Application Number:
07/843909
Publication Date:
10/26/1993
Filing Date:
02/27/1992
Assignee:
Energy and Environmental Research Center Foundation (EERC Foundation) (Grand Forks, ND)"
First, the EERC is an organ of the University of North Dakota.
Second, although the patent is named "Direct Coal Liquefaction Process", coal isn't mentioned in the Abstract.
Instead, as we have been documenting to be possible, the "Process" of "Liquefaction" can be applied to, apparently, any "organic carbonaceous matter"; a somewhat redundant phrase which would include crop wastes (which they have plenty of in North Dakota), sewer sludge, cellulose, scrapped auto tires and at least some waste plastics. The process would have to be so accommodating in order to take advantage of North Dakota's coal deposits. Though generally close to the surface and easy to mine, they are composed primarily of high-ash, lower-Btu lignite, against which some older WV coal mine refuse piles, accumlated prior to the advent of more efficient raw coal cleaning and sorting technologies, might favorably compare in terms of their content of "organic carbonaceous matter".
Third, this technology was developed in the High Plains, also home to the Many Stars CoalTL project we've documented for you numerous times, and the proposed coal conversion project at Malstrom AFB, which might, or might not, still be in the works.
Fourth, finally, and importantly, note that: "In the initial processing step, the finely divided organic carbonaceous material is treated with a hydrocarbonaceous pasting solvent containing from 10% and 100% by weight process-derived phenolic species". As we have in earlier posts documented, "phenols" are a common, most often thought to be objectionable, by-product of some coal use processes, including coke ovens. Coal tar plants make a lot of them in their distillation processes, and some old tar plants, as we have reported, have been classified as toxic waste clean-up sites because of phenols that were "dumped". We have also documented research in other countries suggesting that phenols could be an effective hydrogen donor in coal liquefaction processes.
Once again: Even the wastes arising from our coal use are valuable.