| 摘要 |
1514830 Liquefaction of coal LUMMUS CO 22 Aug 1975 [26 Aug 1974] 35026/75 Heading C5E Coal is treated with a solvent to produce a solution which, after the separation of insoluble material, is separated into a net product and a solvent which is used to treat fresh coal, the solvent comprises a 600‹F+ fraction having at least 70 volume percent thereof boiling from 600‹F to 900‹F and at least 5 volume percent boiling above 900‹F. The liquefaction can be carried out at 700-1000‹F and up to 10,000 psia in the presence or absence of added hydrogen and/or catalyst such as cobalt molybdate, tungsten nickel sulphide or nickel molybdate on alumina or silica. Coal 10 is mixed with solvent 12 and treated in zone 14 and components boiling upto 600‹F are separated from the coal liquefaction product in zone 16. The separation of insoluble materials from a coal solution by gravity separation in zone 23 is improved by the addition of a liquid promoter 21 having a 5 volume per cent distillation temperature of at least 250‹F and a 95 volume per cent distillation temperature of at least 350‹F and no greater than 750‹F. The overflow 24 from separation zone 23 is flashed at 41 to recover a promoter liquid stream 42 and a residue 44 of which a portion 47 is used for preparing the liquefaction solvent 12 and the remainder is separated at 45 into a 900‹F + bottoms 50 and a 600-900‹F fraction 48 of which at least a portion 51 is used for preparing the liquefaction solvent 12. The underflow 31 is separated at 32 into a promoter liquid stream 43, a 600-900‹F fraction 33 and a bottoms 34 which can be calcined, coked or used to produce hydrogen for use in zone 14. Fig. 2 (not shown) illustrates a process in which the flashing column 41 is omitted and the overflow stream 24 is passed directly to a column from which the promoter liquid is recovered as an overhead, the 600-900‹F fraction required for producing the liquefaction solvent is recovered as a sidestream and a bottoms 600‹F+ fraction from which a net product stream 101 and a stream 102 which is incorporated in the liquefaction solvent is also recovered. |
