膜分离与无动力深冷分离技术在聚乙烯尾气回收上的应用

Application of Membrane Separation and Non-power Cryogenic Separation Technology in Recovery of Polyethylene Tail Gas

聚乙烯装置生产出的气体中含有烃类,气体中的部分烃类和氮气被直接排放到火炬中形成了浪费。介绍了目前常用的尾气回收方法,并针对某公司45万t/a聚乙烯装置的实际生产情况,选用合适工艺对该装置的尾气回收系统进行改造。改造后对尾气回收效果进行了标定测算,尾气回收效果达到设计值,能够有效降低全装置的物耗、能耗和异戊烷单耗,很大程度提高了企业的经济效益。

In the production process of polyethylene plant, a lot of hydrocarbon component in the tail gas is discharged by torch, which makes the waste of raw material. In this paper, common exhaust gas recovery methods at present were introduced. Aiming at the actual production status of 450 kt/a polyethylene plant in a company, suitable process was used to transform the tail gas recovery system of the plant. After the transformation, the exhaust gas recovery system was calibrated. The results showed, the effect of tail gas recovery reached the design value;the material consumption, energy consumption and isopentane unit consumption of the whole plant were effectively reduced, increasing the economic benefit.