GB759298A - Process for coal hydrogenation - Google Patents

Abstract

The reaction temperature during the hydrogenation of coal/oil paste under pressure is rapidly reduced when desired, e.g. if it rises near the coking level at about 550 DEG C., by introducing water into the converter while the reaction mixture is undergoing rapid agitation by means of a rotating <PICT:0759298/III/1> stirring device. The converter shown consists of a high-pressure vessel 10 containing a draft tube 11. A shaft 12, with a propeller 13, extends into this draft tube; and causes circulation of the mixture up the tube and down the annular space between the tube and the wall of the converter. Alternatively, the direction of circulation can be reversed. To inject water into the converter, a high pressure pump (not shown) is provided, which connects through pipe 14 to feed-line 15 going into the base of the converter, so that the water and steam passes up draft tube 11 where it intimately mixes with the circulating stream of coal paste and hydrogen. The coal hydrogenation products flow down overflow pipe 16, and leave the converter through pipe 17. In an example, bituminous coal dispersed in pasting oil is hydrogenated at a pressure of 4500 psi and at a temperature of 535 DEG C.; and the converter contains 9 pounds of material. When, during a period of 6 minutes, 0.6 pounds of water are injected into the converter there is a drop in temperature of 25 DEG C. to 50 DEG C., and the rate of reaction is materially reduced.