Coal liquefaction process
AssigneeThe Pittsburg & Midway Coal Mining Co.
InventorsNorman L. Carr, William G. Moon, Michael E. Prudich
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Abstract
A C.sub.5 -900.degree. F. (C.sub.5 -482.degree. C.) liquid yield greater than 50 weight percent MAF feed coal is obtained in a coal liquefaction process wherein a selected combination of higher hydrogen partial pressure, longer slurry residence time and increased recycle ash content of the feed slurry are controlled within defined ranges.
Claims10
A coal liquefaction process for producing a C.sub.5 -900.degree. F. liquid yield greater than 50 weight percent MAF coal, which comprises passing hydrogen and a feed slurry comprising mineral-containing feed coal, recycle normally solid dissolved coal, recycle mineral residue and a recycle liquid solvent to a coal liquefaction zone, recycle ash being present in said feed slurry in an amount greater than about 8 weight percent based on the total feed slurry, said feed slurry containing from 20-35 wt. percent coal, said feed slurry being reacted in said coal liquefaction zone under a hydrogen partial pressure of from about 2,100 and about 4,000 psi at a temperature in the range of 430.degree.-470.degree. C., under threephase, backmixed, continuous flow conditions at a nominal slurry residence time of from about 1.2 to about 2 hours, the values for said recycle ash, hydrogen partial pressure and slurry residence time being selected to produce a C.sub.5 -900.degree. F. liquid yield of between about 50 to about 70 weight percent based upon MAF coal.
Dependencies are inferred from the claim text.