Application of Double-expansion Self-cryogenic Separation Technology in Vent Gas Recovery of Polyethylene Loop Slurry Plants
1. Hebei Special Equipment Supervision and Inspection Institute, Handan 056017, China;
2. College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
Abstract:The vent gas recovery of polyethylene loop slurry plant has significant economic value. After analyzing the shortcomings of the existing recovery process systems, the double-expansion self-cryogenic separation recovery system was designed in order to improve the recovery ratios and concentration of hydrocarbon and nitrogen, while reducing the operating energy consumption. The simulation results showed that the recovery ratios of ethylene and isobutane could reach 99.34% and 99.99% respectively, the nitrogen concentration in the recovered nitrogen was 96.3%, and the energy consumption of compressor was reduced by at least 46%. It could be seen that the application of double-expansion self-cryogenic separation technology has greatly improved the recovery ratio of hydrocarbon, reduced the materials loss and the operating energy consumption, which is a promising technology of vent gas recovery.
HE Linbo1,LIAO Zuwei2,HUANG Zhengliang2 et al. Application of Double-expansion Self-cryogenic Separation Technology in Vent Gas Recovery of Polyethylene Loop Slurry Plants[J]. 化学反应工程与工艺, 2020, 36(4): 379-384.