膜法协同氢气分离-脱水改进STAR工艺  

Synergic hydrogen separation and dehydration via glassy membrane unit for STAR PDH technology

作　　者：肖红岩 张宁 郭明钢 XIAO Hong-yan;ZHANG Ning;GUO Ming-gang(State Key Laboratory of Fine Chemicals,School of Petroleum and Chemical Engineering,Dalian University of Technology,Panjin 124221,China)

机构地区：[1]大连理工大学盘锦校区石油与化学工程学院精细化工国家重点实验室

出　　处：《现代化工》2020年第2期201-205,共5页Modern Chemical Industry

基　　金：国家自然科学基金项目(21606035,U1663223)

摘　　要：STAR丙烷脱氢工艺中深冷单元操作条件为3.20 MPa、-78℃,一方面反应产物中大量氢气随之压缩,另一方面需深度脱水,能耗高。可通过在产物预冷之后采用膜分离协同分离氢气、脱除水分并进行梯级压缩来改进该工艺。以35万t/a STAR工艺为例,引入3 000 m^2的prism-Ⅱ膜单元进行改进后,渗余气含水质量分数降至0.9×10^-6,可省去干燥塔及解吸气压缩功190 k W;同时,梯级压缩功为6540 k W,较改进前节约310 k W;氢气摩尔分数由82.8%提高到95.9%,年产氢量约1.24亿m^3,新增经济效益9 070万元/a。In STAR propane dehydrogenation(PDH)process,the operating conditions for cryogenic unit include3.20 MPa and-78℃.On the one hand,a considerable amount of hydrogen is compressed with reaction effluent;on the other hand,the process needs deep dehydration,which leads to excessive energy consumption.In this work,hydrogen separation membrane is utilized behind the products pre-cooling unit to perform synergic hydrogen separation,dehydration and cascade compression.Taking a typical 350 000 t/a STAR PDH plant for instance,if a 3 000 m^2Prism-II membrane unit is added,the water content in residual gas can be reduced to 0.9×10^-6,which can omit the drying tower and save190 k W of energy consumption in desorption gas compression.Meanwhile,the power for cascade compression is 6 540 k W,310 k W lower than that in the traditional process.The mole fraction of hydrogen can be improved from 82.8% to 95.9% and the hydrogen production is around 124 million Nm3/a.Annual gross profit can be increased by RMB90.7 million.

关 键 词：丙烷脱氢 膜分离 过程模拟 优化设计 节能 

分 类 号：TQ028[化学工程]