GB1277252A - Hydrocarbon separation process - Google Patents

Abstract

1277252 Separating hydrocarbons; cracking UNIVERSAL OIL PRODUCTS CO 25 Sept 1969 47151/69 Heading C5E The fluid effluent 12 from the coking of a vacuum reduced crude oil at 900‹ F. and; 75 p.s.i.g. is fractionated at 13 at 820‹ F. and 75 p.s.i.g. to provide an overhead stream 14 comprising normally gaseous material and gasoline at' 302‹ F., a side-cut stream 15 comprising light gas oil at 585‹ F. and a bottoms stream 16 comprising heavy gas oil at 750‹ F. The stream 14 is cooled to 100‹ F. and separated at 17 into a liquid stream 19 and a gaseous stream 18 which is then compressed to 225 p.s.i.g., mixed with recycle stream 21 and separated at 23 to produce a gaseous stream 24 and a liquid stream 25. The stream 25 is fractionated in a zone 32 which comprises a gasoline stripper operated at 140‹ F. and 242 p.s.i.g. to separate a stream 33 of C 2 and light components- and a debutanizer column operated at 400‹ F. and 195 p.s.i.g. to separate a stream 36 of C 3 and C 4 hydrocarbons and a gasoline stream 34. The gas stream 24 is passed to absorption zone 26 at 100‹ F. and 212 p.s.i.g. to dissolve substantially all of the C 3 and C 4 hydrocarbons into the absorbent which comprises the lean oil stream 19 and part of the gasoline stream 35. A gas stream 27 comprising C 2 and lighter hydrocarbons and a liquid stream 21 which is recyled to the separator 23 along with gaseous material from line 37 are produced from the absorption zone 26. The gas stream 27 is passed to a second absorber 28 at 118‹ F. and 205 p.s.i.g. and contacted with a countercurrent of lean oil 29 from the fractionation zone 13 to dissolve C 3 compounds leaving a gaseous stream 30 and a rich oil stream 31 which is recycled to the fractionation column 13 as reflux. A portion of the gasoline stream 35 can be passed to the fractionation zone 13, the separation zone 17 or the separation zone 23.