有机胺吸收CO2反应热实验

摘要

采用自主开发的CO2反应热测试研究系统,测量伯胺MEA(乙醇胺)和仲胺DEA(二乙醇胺)在不同温度、不同质量分数和不同压力下的CO2的吸收量和吸收反应热,计算不同体系的脱除率,对其进行对比分析研究;测量不同温度下MEA和DEA溶液的解吸反应热,并对解吸反应的边界进行分析探讨.结果表明:反应热随温度、压力升高而增大,随质量分数升高稍有升高;解吸反应的结束边界是通过观察冷凝水的出液情况判断的,一种是分散的液滴,另一种状态是液塞形成桥塞管路状,平衡状态反应器内余压约为1.5 kPa,气体流量趋近零;不同温度、不同质量分数和不同压力下MEA溶液吸收反应热范围为80～100 kJ/mol,解吸反应热范围为100～140 kJ/mol,DEA溶液吸收反应热范围为50～80 kJ/mol,解吸反应热范围为70～100 kJ/mol;DEA溶液吸收量随各吸收工况的变化趋势与MEA基本一致,DEA溶液的吸收能力仅有MEA溶液的一半,但解吸脱除率普遍高于60%,解吸能力较MEA强.%The self-developed CO2reaction heat testing system was applied to determine the CO2absorption capacity, absorp-tion reaction heat under different temperatures, different concentrations and different pressures of ethanolamine ( MEA) and diethanolamine (DEA).Then the removal rates of different systems were calculated and analyzed.The heat of desorption of MEA and DEA solution at different temperatures were measured, and the boundary of desorption reaction was analyzed as well.The results indicate that the reaction heat increases with the increase of temperature and pressure.However, the reac-tion rate improves slightly with the increase of pressure.The end boundary of desorption reaction can be determined through the conditions of the condensed water outlet, which are dispersed droplet and slug formed plug pipeline,respectivrly.In the latter situation, the equilibrium reactor pressure is about 1.5 kPa, and the gas flow rate is closed to zero.Under different temperatures, concentrations, and pressures, the reaction heat range of MEA solution absorption is 80-100 kJ/mol, and the reaction heat range of desorption is 100-140 kJ/mol.The reaction heat range of DEA solution absorption is 50-80 kJ/mol, and the reaction heat range of desorption is 70-100 kJ/mol.The change of absorption capacity of DEA solution with various absorption conditions is consistent with that of MEA.The absorption capacity of DEA solution is only about half of MEA, but the desorption rate is generally higher than 60%, meaning the desorption ability is stronger than MEA.