炼厂气膜分离氢回收装置的控制

介绍了膜分离技术在炼厂气氢回收中应用的工艺流程及控制要求,设计了基于DCS/FSC的控制系统.膜分离装置采用了TBM中低压膜,并首次使用了两段分离设计,公称处理量达11 000 m3/h,操作弹性为30%～130%,设计年开工时间为8 400 h,可产氢气6 798 m3/h,其中氢气体积分数大于91%,氢气回收率大于85%.膜分离装置的基本控制回路主要包括水冷器出口温度、旋风分离器液位、原料气人膜压力及一段、二段渗透气压力、操作温度等.通过在镇海炼油化工股份有限公司的应用证明,该工艺流程设计合理,控制系统安全可靠,整套系统取得了较高的经济效益.

CONTROL OF MEMBRANE SEPARATION PROCESS FOR HYDROGEN RECOVERY FROM REFINERY GAS

The process flow and process control requirements of membrane separation for hydrogen recovery from refinery gas are described. The control systems based on DCS and FSC were designed. Two-stage membrane separation unit of TBM medium-low pressure modules is installed to process the gas stream at a capacity of 11,000 Nm3/h with a turndown ratio of 30%-130% . The design on-stream time is 8 ,400 h/yr, hydrogen production is 6,798 Nm3/h with H2 purity greater than 91% and H2 recovery rate higher than 85% . The basic control loops of the unit include water cooler outlet temperature, cyclone separator level, feed gas pressure, permeation gas pressures and operating temperatures of 1st and 2nd-stages. The successful application in Zhenhai Refining and Chemical Co. , Ltd. has approved that the process design is optimized, the control systems are safe and reliable and economic benefits are significant.