强弱极性联合吸收工艺处理氯醇化尾气的研究

Study on treatment of chlorohydrin tail gas by combined absorption process of strong and weak polarity

在氯醇法生产环氧丙烷工艺中,由于丙烯次氯酸化制取氯丙醇车间的氯醇化尾气中含有酸性腐蚀组分、可燃气体、共沸有机氯化物、氧气等,综合回收利用较为困难。目前,采用不可再生的碱洗、焚烧、深冷、鼓入空气稀释等方法来处理,效果差,能耗高,危险系数大,而且会产生二恶英。本研究采用固体碱吸收酸性腐蚀组分后,根据物性特点分别采用强极性溶剂和弱极性溶剂耦合吸收的工艺对氯醇化尾气回收处理,同时回收丙烯、丙烷和有机氯化物。探讨了不同吸收剂流量下尾气的吸收效率和最优操作条件,结果表明采用强-弱极性联合工艺能有效回收尾气中产品附加值,丙烯丙烷回收率为98%以上,有机氯化物回收率97%以上,且该工艺过程能耗低,绿色环保,应用前景广阔。

In the production of propylene oxide by the chlorohydrin method,the chlorohydrin tail gas of the chlorohydrin production workshop due to the hypochlorination of propylene contains acidic corrosion components,combustible gases,azeotropic organic chlorides,oxygen,etc.,comprehensive recycling is difficult.Non-renewable methods such as alkali washing,incineration,cryogenic cooling,and air blowing dilution are used to treat chlorohydrin tail gas,which has poor effect,high energy consumption,high risk factor,and will produces dioxins.In this study,solid alkali was used to absorb the acidic corrosion components,and the chlorohydrin tail gas was recovered and treated by the coupling absorption process of strong polar solvent and weak polar solvent according to the physical characteristics,and propylene,propane and organic chloride were recovered at the same time.The absorption efficiency and optimal operating conditions of the tail gas under different absorbent flow rates were discussed.The results show that the combined process of strong and weak polarity can effectively recover the added value of products in the tail gas.The recovery rate of propylene and propane is 98%,and the recovery rate of organic chloride is 97%.%,and the process has low energy consumption,green environmental protection,and broad application prospects.