苯乙烯装置脱氢尾气处理系统堵塞的原因分析

摘要

简要介绍了脱氢尾气处理系统工艺流程及运行过程中出现的问题:压缩机出口分液罐内生成大量聚合物、压缩机出口管线堵塞、压缩机出口冷却器壳程严重堵塞、吸收塔塔底泵电流经常超出额定值.分析了脱氢尾气压缩机出口管线及设备产生聚合物并堵塞的原因和机理.空气冷却器冷却能力不足,压缩机入口温度偏高,脱氢尾气中的苯乙烯含量高,苯乙烯在70℃条件下发生自聚反应是造成尾气处理系统堵塞的根本原因.提出了增加两台空气冷却器和一台深冷器的改造措施,增加空冷器可以将空冷器出口温度降低约10℃,增加深冷器可以降低压缩机入口温度至20℃左右,这将大幅度降低脱氢尾气中苯乙烯含量,降低压缩机出口温度,从源头上解决脱氢尾气处理系统聚合堵塞的问题.%The process and problems in the operation of dehydrogenation tail gas treatment system are described briefly:such as a large amount of polymers are produced in the knock-out drum at the compressor outlet,the compressor outlet pipeline is plugged,the shell side of the cooler at compressor outlet is seriously blocked,and electric current of absorption tower kettle pump is often higher than the rating.The causes and mechanisms of the production of polymers and blockages in the outlet pipeline and equipment are analyzed.It is found out that the root causes of blocking of tail gas treatment system are insufficient cooling capacity of air coolers,higher compressor inlet temperature,higher styrene in dehydrogenation tail gas,and auto-polymerization under the temperature of 70 ℃.It is recommended to install two additional air coolers and one deep freezer.The addition of air coolers can reduce the outlet temperature of air cooler to about 10 ℃.The installation of deep freezer can lower the inlet temperature of compressor to about 20 ℃.This measure will greatly reduce the styrene content in the dehydrogenation tail gas and lower the outlet temperature of the compressor,and solve the polymerization and blockage problems of the dehydrogenation tail gas treatment system from the sources.