| 摘要 |
1,238,410. Coking liquid hydrocarbons. LUMMUS CO. 15 July, 1969 [15 July, 1968], No. 35606/69. Heading C5E. In a process for the delayed coking of a non- petroleum derived liquid hydrocarbon fraction, e.g. coal tar pitch, having a high content of condensed ring aromatics and an I.B.P. not less than 600‹ F., an overhead is recovered from the coking zone and a portion at least is recycled to a heating zone preceding the coking zone in a volume ratio in the range 0À3:1 to 0À6:1 based on the total feed (fresh and recycle) to the heating zone. The heating zone is operated at a temperature in the range 900‹ to 960‹ F., and the coking zone in the range 840‹ to 900‹ F., and turbulence is maintained in the heater, e.g. by introducing steam, to prevent premature coking. Before going to the heater, both the recycled and preheated fresh feed are delivered to a coker-combination-fractionater, where gases and vapours are flashed off, and a heavy oil (I.B.P. 600‹ to 750‹ F.) recovered and recycled, after cooling, to the fractionater. |
