乙烯环氧化固定床膜反应器性能CFD模拟分析

CFD analysis of ethylene epoxidation in a packed-bed membrane reactor

为了提高乙烯氧化合成环氧乙烷反应体系的选择性,建立了乙烯由膜管进料的固定床膜反应器模型,对其进行了相关的计算流体力学(CFD)计算模拟,并与传统固定床反应器作比较。结果表明:在反应器构型、催化剂、反应条件相同的前提下,相较于传统固定床反应器而言,固定床膜反应器的选择性较高但乙烯转化率和环氧乙烷收率较低;改变操作条件使得两种反应器的选择性相同时,固定床膜反应器中乙烯转化率和环氧乙烷收率较大。据此得出固定床膜反应器较传统固定床反应器更具优势的结论。本文工作为乙烯环氧化固定床膜反应器的放大与固定床膜反应器替代传统固定床反应器的可行性提供了理论基础。

A packed-bed membrane reactor,in which ethylene is fed to the center tube and then permeates through the membrane,was analyzed by CFD in an attempt to increase the ethylene oxide selectivity. Comparison with a fixed-bed reactor under the same operating conditions showed that the selectivity to ethylene oxide of the packedbed membrane was higher but the ethylene conversion and the yield of ethylene oxide were lower. Based on this,simulations of both reactors were carried out with the same selectivity under different operating conditions. The results showed that the ethylene conversion and the yield of ethylene oxide of the packed-bed membrane were higher.It is concluded that the packed-bed membrane reactor has an obvious advantage over the fixed-bed reactor,and this work provides a theoretical basis for the scaling up of a packed-bed membrane reactor and the feasibility of replacing a conventional fixed-bed reactor with a packed-bed membrane reactor.