有机胺基氨基酸盐混合吸收剂对沼气中CO_2的分离特性  

Performance of CO_2 removal from biogas by using amine-based amino acid salts blended absorbents

作　　者：贺清尧 蔡凯[1] 晏水平[1] 艾平[1] 王媛媛[1] 张衍林[1] 

机构地区：[1]华中农业大学工学院,湖北武汉430070

出　　处：《化工进展》2015年第3期857-862,878,共7页Chemical Industry and Engineering Progress

基　　金：国家自然科学基金项目(51376078;51006044)

摘　　要：在鼓泡式CO2吸收和再生装置中,研究了N-甲基二乙醇胺(MDEA)/乙醇胺(MEA)、MDEA/乙醇胺基甘氨酸(MEAGLY)和MDEA/乙醇胺基肌氨酸(MEASAR)混合吸收剂的沼气CO2吸收及再生特性。结果表明:混合吸收剂的沼气CO2吸收速率随MEA、MEAGLY和MEASAR等添加剂添加量的增加而提高,但再生速率却呈现下降趋势。再生过程中,吸收剂在升温阶段均发生了CO2再生,且混合吸收剂再生效果要优于单一吸收剂。综合考虑CO2吸收速率、再生速率和CO2循环携带量,MDEA与活化剂质量配比为3∶2时所组成的混合吸收剂的沼气CO2吸收-再生综合性能最优。沼气CO2分离成本对比分析显示,与质量分数为30%的MEA相比,总质量分数为30%的MDEA/MEAGLY(3∶2)和MDEA/MEA(3∶2)的CO2分离成本可分别下降约12%和30%,在未来具有替代MEA进行工程应用的潜能。This paper investigated the CO2 absorption performance from biogas and regeneration characteristics using N-methyldiethanolamine-based（MDEA）blended solvents respectively promoted by monoethanolamine（ MEA）, MEA-based glycinate（ MEAGLY） and MEA-based sarcosinate（ MEASAR） in a bubbling CO2 absorption/regeneration reactor. Results showed that the CO2 absorption rates of blended solvents increased with the adding amount of promoters, but CO2 desorption rates decreased. During the period of temperature increase from the absorption range to regeneration range, all the CO2-rich solvents were regenerated, and the blended solvents performed better than the single solvents in CO2 regeneration efficiency. In addition,when mass ratio of MDEA to promoter was 3 ∶ 2 in the blended solvents, the absorption-regeneration performances were optimal.CO2 removal costs from biogas of different absorbents were also assessed and compared. Compared to the single MEA with 30% mass fraction,the blended solvents,MDEA/MEAGLY and MDEA/MEA in which the total mass fraction was 30% and the ratio of MDEA to MEAGLY or MEA was 3﹕2 had the lower CO2 removal costs by about 12% and 30%,respectively. So MDEA/MEAGLY and MDEA/MEA might be the promising alternatives to replace MEA in the future.

关 键 词：沼气提纯 有机胺基氨基酸盐 混合吸收剂 吸收 二氧化碳再生 

分 类 号：S216.4[农业科学—农业机械化工程]