反应条件对MEA溶液提纯沼气传质性能的影响  

Effect of Reaction Conditions on Mass Transfer Performance of CO_2 Absorption by Monoethanolamine Solution for Biogas Purification

作　　者：李虎[1] 刘应书[1,2] 张辉[1,2] 焦璐璐 李皓琰[1] 

机构地区：[1]北京科技大学机械工程学院,北京100083 [2]北京科技大学北京高校节能与环保工程研究中心,北京100083

出　　处：《农业机械学报》2015年第1期185-191,共7页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家高技术研究发展计划(863计划)资助项目(2012AA101802-3);中央高校基本科研业务费专项资金资助项目(FRF-SD-12-013A)

摘　　要：对吸收剂浓度、进气流量及CO2体积分数、进液温度等反应条件对MEA溶液吸收沼气中CO2过程的八田数Ha、增强因子E及总体积传质系数KGae的影响进行了实验研究,并对吸收过程中反应对传质性能的影响及拟一级反应的条件进行了分析。结果表明:吸收过程中的八田数Ha、增强因子E及总体积传质系数KGae随吸收剂浓度增加而增大;随进气中CO2体积分数增加而减小;当进气流量增加时,Ha、E减小,KGae先增大后减小;Ha、E及KGae随吸收温度增加而增大,当吸收温度高于57.4℃时,KGae逐渐减小。在此条件下,仅当吸收剂浓度高于2.5 mol/L或者进气流量低于5.73 kmol/(m2·h)时,MEA与CO2的反应可用拟一级反应描述。研究结果可为沼气提纯工艺的优化及技术开发提供参考。The removal of CO2 with aqueous alkanolamine solutions is an important research direction in the field of biogas purification technology, and the research on the kinetics and mass transfer performance of the CO2 absorption is the mainly theoretical basis of optimizing biogas purification process. In the process of using monoethanolamine （MEA） aqueous solution, the Hatta number Ha, enhancement factor E and volumetric overall mass transfer coefficient Kcae were studied experimentally at various reaction conditions, such as MEA concentration, gas flow rate, CO2 concentration, and absorption temperature. Furthermore, the impact on the mass transfer performance of reaction and the premise of applying the pseudo-first-order reaction were also analyzed. The results show that the values of Ha, E and Kcao increase with increasing MEA concentration but decrease with increasing CO2 concentration. When the gas flow rate is increased, Ha and E decrease, while KGae initially increase and then decrease. The above parameters increase with increasing absorption temperature, and Kcae gradually decrease when the temperature is higher than 57.4℃. Under the experimental conditions, only when the absorbent concentration is higher than 2.5 mol/L or the gas flow rate is lower than 5.73 kmol/（ms. h）, the reaction of MEA and CO2 can be described as a pseudo-first-order reaction. The results can provide a reference for the optimization and development of biogas purification technology.

关 键 词：沼气提纯 一乙醇胺 传质系数 八田数 增强因子 

分 类 号：TK6[动力工程及工程热物理—生物能]