Coal hydrogenation process with direct coal feed and improved residuum conversion

摘要

A process for hydrogenation of coal to produce hydrocarbon liquids and gases, wherein the yield of liquid products is increased by feeding particulate coal at temperature below about 600 DEG F. directly into a back-mixed reactor and preferably into an ebullated bed catalytic reaction zone containing coal-derived liquid and hydrogen for rapid heating and conversion. In the process, the coal is pressurized and fed without preheating directly into the reaction zone and additional heat needed in the reaction zone to maintain temperature therein at 750 DEG -900 DEG F. is provided by heating recycle hydrogen and coal-derived liquid streams to temperatures above the desired reaction zone temperature. By using this process, the coal feed is heated quickly and hydrogenated in the catalytic reaction zone and undesired thermal reactions which usually occur in coal during preheating before its exposure to the catalytic hydrogenation reaction zone conditions are minimized, which results in increased yields of desirable light hydrocarbon liquids products and reduced production of undesirable asphaltenes and unconverted coal or char.