| 摘要 |
PURPOSE: A hydroprocessing process comprising two stages is provided to increase the yield of the middle distillate, reduce the volume of the recycled stream, and reduce the need for the equipment for treating the recycled stream. CONSTITUTION: The hydroprocessing process comprises the steps of: (a) passing a hydrocarbon feed(1) into a first reaction stage(3); (b) combining the effluent(5) with the product(25) from the second reaction stage(15) and passing the combined stream(6) to a separation zone(7); (c) separating the stream of step (b) into an unconverted liquid effluent(13) and at least one converted stream; (d) passing the liquid effluent(13) to a second reaction stage(15) maintained under hydrocracking conditions; (e) contacting the feed in the first reaction zone of step (d) with a catalyst(16); (f) separating the effluent(17) into an unconverted liquid effluent(20) and a hydrogen-rich converted stream(21); (g) recycling the converted stream(21) to combine with the effluent of step (a); (h) passing the unconverted liquid effluent(20) to a second reaction zone of the second reaction stage(15); (i) contacting the feed in the second reaction zone of step (h) with a catalyst(23); (j) fractionating the effluent(24) of step (i) to produce a gas, naphtha and one or more middle distillate product streams.
|
