用于捕集CO2的相变吸收剂与乙醇胺吸收剂性能对比

Performance comparison between phase change absorbent and ethanolamine absorbent for CO2 capture

关键词:  二氧化碳  碳捕集  相变吸收剂  吸收  解吸  腐蚀  再生能耗

Key words:  carbon dioxide  carbon capture  phase change absorbent  absorption  desorption  corrosion  regenerative energy consumption

摘要:

目的 解决传统吸收剂捕集二氧化碳（CO₂）存在的再生能耗和经济成本较高等问题，研发新型相变吸收剂。方法 对4种相变吸收剂体系：DETA-1-propanol、MMEA-DEG、DEEA-MEA和DEEA-AEEA的性能进行了对比研究，以传统吸收剂质量分数为30%的乙醇胺（MEA）溶液作为参考基准，进行吸收、解吸、发泡、腐蚀、循环吸收-解吸实验研究以及再生能耗和成本估算。结果 DETA-1-propanol体系的富相体积占总体积的66%，最大吸收负荷为3.34 mol/kg，与MEA吸收剂相比提高了54.6%。溶剂成本为11 500元/t，相比MEA吸收剂增加了35.5%，再生显热（以每1 t CO₂计）为0.28 GJ/t，再生潜热为1.1 GJ/t，与MEA吸收剂相比分别降低了73.3%和12.0%。结论 DETA-1-propanol吸收剂体系具有较高的吸收、解吸性能和较高的循环稳定性，以及较低的再生能耗和溶剂成本。

Abstract:

Objective The aim is to solve the problems of high regeneration energy consumption and high economic cost in the capture of carbon dioxide(CO₂) by traditional absorbents, and to develop new phase change absorbents. Methods This paper provided a comparative study of the performance of four phase change absorbent systems: DETA-1-propanol, MMEA-DEG, DEEA-MEA, and DEEA-AEEA. Using monoethanolamine (MEA) with a traditional absorbent mass fraction of 30% as a reference standard, experiments were conducted to study absorption, desorption, foaming, corrosion, cyclic absorption-desorption, as well as estimated regeneration energy consumption and costs. Results The DETA-1-propanol system had a rich phase volume accounting for 66% of the total volume, with a maximum absorption capacity of 3.34 mol/kg, representing a 54.6% improvement compared to 30% MEA absorbents. The solvent cost was 11 500 yuan/t, which increased by 35.5% compared to 30% MEA absorbents. The regeneration enthalpy was 0.28 GJ/t CO₂, and the regeneration latent heat was 1.1 GJ/t CO₂. Compared with MEA absorbent, it reduced by 73.3% and 12.0%, respectively. Conclusions The DETA-1-propanol absorbent system exhibits higher absorption and desorption performance, high cycling stability, as well as lower regeneration energy consumption and solvent cost.