膜分离法、化学吸收法以及联合法分离CO_2/CH_4试验比较

Experimental Study on CO_2/CH_4 Separation Respectively by Membrane,Chemical and the Combined Method

在中空纤维膜和化学吸收塔的试验台上,分别采用膜分离法、化学吸收法进行了CO2/CH4混合气体的分离试验.在此基础上提出了联合法新型CO2脱除技术,并在中空纤维膜串联化学吸收塔的试验台上进行了CO2/CH4混合气体分离试验,重点考察了各影响因素对各分离方法脱碳效果的影响,并对各分离方法脱碳效果进行了对比.结果表明:膜分离法的脱碳效率低且CH4损失率高,适用于处理小流量且对脱碳效率要求不高的工艺;化学吸收法的脱碳效率和CH4回收率高,适用于分离纯度要求高的工艺;联合法脱碳效率偏低但CH4损失率低,适用于处理大流量且对脱碳效率要求不高的工艺.

Separation efficiencies of CO2/CH4 by membrane separation and chemical absorption were stud- ied respectively in a hollow fiber membrane contactor test rig and a packed tower test rig, and subsequently a new CO2 removal technology was proposed. CO2/CH4 separation experiments were carried out in the new test rig combining the hollow fiber membrane with the packed tower, so as to analyze the influence of vari- ous factors on the CO2 removal effect, and to compare the CO2 removal efficiency among the three separa- tion methods. Results show that the membrane separation has low CO2 removal efficiency and low CH4 re- covery ratio, which suits to deal with the gas of small flow rate with undemanding separation efficiency; the chemical absorption has high separation efficiency and high CH4 recovery ratio, which suits to process the gas with demanding separation efficiency; the combined method has low separation efficiency and high CH4 recovery ratio, which suits to deal with the gas of high flow rate with undemanding separation effi- ciency.