N-氨乙基哌嗪与甘氨酸钠CO_(2)吸收剂配方研究

Formulation Study of N-Aminoethyl Piperazine and Sodium Glycine CO_(2) Absorbent

化学吸收法是捕集燃煤电厂烟气中CO_(2)应用最为广泛的技术之一,但其存在吸收容量较低及再生能耗较高等问题,因此开发新型高效CO_(2)吸收剂代替传统单乙醇胺(MEA)吸收剂是当前研究的重点之一。以质量分数为30%的MEA作为参考标准,研究不同配比的N-氨乙基哌嗪(AEP)+甘氨酸钠(SG)复配溶液对CO_(2)的吸收和解吸性能,通过添加不同助剂调节溶液pH值提高吸收剂再生性能,通过对比吸收剂的吸收量、吸收速率、解吸量、解吸速率、吸收-解吸循环性能以及再生能耗,优选出35%AEP+5%SG+1%柠檬酸为最优复配吸收剂。结果表明,配比为35%AEP+5%SG+1%柠檬酸吸收剂CO_(2)吸收量3.70mol/L,解吸量为3.55mol/L,解吸率达96.05%,单位再生能耗为136.75 kJ/mol,与质量分数30%MEA相比,吸收量提高1.18倍,解吸量增加2.17倍,解吸率提高30.93%,再生能耗下降33.90%。经过10次循环试验后,该复配溶液循环稳定性良好,再生性能较优,具有潜在的应用价值。

Chemical absorption method is one of the most widely used technologies to capture CO_(2) from flue gas of coal-fired power plants,but it has problems of low absorption capacity and high regeneration energy consumption.Therefore,it is one of the current research focuses to develop a new efficient CO_(2) absorbent to replace the traditional monoethanolamine(MEA)absorbent..To study the CO_(2) absorption and desorption performance of aminoethylpiperazine(AEP)+sodium glycinate(SG)complex solution with different proportions,30%MEA was used as a reference standard.By adding different additives to adjust the pH value of the solution,the regeneration performance of the absorbent was improved.According to the absorption capacity,absorption rate,desorption capacity,desorption rate,absorption-desorption cycle performance and regeneration energy consumption of the absorbent,35%AEP+5%SG+1%citric acid was selected as the best compound absorbent.The results show that the ratio of 35%AEP+5%SG+1%citric acid absorbent CO_(2) absorption is 3.70 mol/L,desorption capacity is 3.55 mol/L,desorption rate is 96.05%,unit regeneration energy consumption is 136.75 kJ/mol.Compared with 30%MEA,the absorption capacity is increased by 1.18 times,desorption capacity is increased by 2.17 times,desorption rate is increased by 30.93%,and regeneration energy consumption is decreased by 33.90%.After 10 cycle tests,the compound solution has good cycle stability and good regeneration performance,and has potential application value.