乙醇胺/N-甲基二乙醇胺/三乙烯四胺体系吸收烟气CO_2的研究

Effects of TETA on MEA-MDEA amine solution in recovering carbon dioxide from flue gas

在乙醇胺(MEA)/N-甲基二乙醇胺(MDEA)体系(简称二元复合胺体系)中加入少量活化剂三乙烯四胺(TETA),研究了MEA/MDEA/TETA三元复合胺体系(简称三元复合胺体系)对烟气CO2的吸收和再生情况。结果表明,MEA、MDEA、TETA3种组分之间存在交互作用,使得三元复合胺体系中的CO2吸收速率、CO2饱和吸收量均分别小于二元复合胺体系与TETA单体系的CO2吸收速率、CO2饱和吸收量之和。三元复合胺体系的再生温度稍高于二元复合胺体系,其一次再生率约为83.5%,比二元复合胺体系低了约13百分点,三元复合胺体系的再生较二元复合胺体系更困难。

The research of CO2 recovery from flue gas has focused on using efficient mixed amine CO2 absorption solutions which can remove large amounts of at fast rates and that the spent solutions can be regenerated simply and quickly. Effectiveness of various mixed amine solutions of MEA,MDEA,and TETA in removing CO2 from a simulated flue gas and regeneration of the spent solutions were studied. The initial CO2 release temperature,mixed amine regeneration temperature,regeneration rate and the pH decline of the regeneration were monitored. The results have demonstrated that CO2 absorption rate,absorption capacity,desorption rate,pH and temperature are interrelated. The addition of TETA to the MEA-MDEA solution reduced its CO2 removal rate,that the combined capacity was lower than the sum of the two,and that the spent three-amine solutions were more difficult for regeneration.