COAL HYDROGENATION PROCESS USING THERMAL COUNTERCURRENT FLOW REACTION ZONE

摘要

ABSTRACTThermal hydrogenation of coal to produce hydrocarbonliquid and gas products is performed in a thermal reactionzone, in which a coal/oil slurry flows generally downwardlycountercurrent to upflowing hydrogen. An effluent streamcontaining light hydrocarbon liquid and gas is withdrawnfrom the thermal reaction zone upper end, and a heavy liquidstream containing unconverted coal and ash is withdrawn fromthe reaction zone bottom end. Both streams are passed tophase separation and distillation steps for recovery ofhydrocarbon gas and liquid products. A portion of the lightliquid effluent is preferably recycled to the reaction zonelower end for upflow therein to help increase coal residencetime and for further hydrogenation reaction. If desired,the heavy liquid bottoms stream from the thermal reactionzone and containing unconverted coal and ash can be passedwith additional hydrogen to a second catalytic reaction stepfor further hydrogenation reaction to increase the yield oflower-boiling hydrocarbon liquid products.