化工学报2025，Vol.76Issue(4)：1375-1390,16.DOI:10.11949/0438-1157.20240963
吸附法CO2直接空气捕集技术能耗现状
Current status of energy consumption of adsorption CO2 direct air capture
摘要
Abstract
Compared to traditional fixed source flue gas capture technologies,CO2 direct air capture(DAC)has advantages such as flexible positioning and wide application.However,due to the extremely low concentration of CO2 in the atmosphere(only around 0.04%),the high energy consumption of DAC has become the primary obstacle to its commercialization.Focusing on the energy consumption issue of adsorption based DAC,theoretical analysis and case studies have been conducted.The ideal minimum work for CO2 separation of DAC was calculated to be 19.64 kJ·mol-1(temperature of 298.15 K,capture ratio of 50%,purity of 95%),which is 3.5 times that of flue gas capture technology under the same conditions.At a regeneration temperature of 393 K,the second law separation efficiency of temperature vacuum swing adsorption cycle(TVSA)is 22.75%.The processes of adsorption,evacuation,regeneration,condensation,compression,etc.,are mainly driven by mechanical and thermal energy.The mechanical energy during the evacuation process accounts for only about 3%of the total energy consumption.The heat energy during the condensation process can be recovered through a regenerative cycle.The mechanical energy of the compression process is included in DAC in some studies and is determined by the target pressure.The flow mechanical energy during the adsorption process accounts for over 90%of the mechanical energy consumption,which is 5.43 GJ·t-1 when using a conventional reactor.Structured reactors can reduce pressure drop to 1/1000,and reducing flow rate can also improve resistance and enhance capture ratio.The thermal energy during the regeneration process accounts for the main part of DAC energy consumption,about 50%—80%.The regeneration temperature,the mass ratio of the reactor to the adsorbent,and the strength of the adsorbent's adsorption of H2 O can all cause a multiple change in the heat consumption.Based on the analysis of the process energy consumption,recommendations for optimizing the energy consumption of adsorption DAC in terms of reactor design,circulation mode and operating parameters,natural environment and energy sources are given.关键词
二氧化碳捕集/能耗/吸附/脱附/温室气体Key words
CO2 capture/energy consumption/adsorption/desorption/greenhouse gas分类
资源环境引用本文复制引用
赵俊德,周爱国,陈彦霖,郑家乐,葛天舒..吸附法CO2直接空气捕集技术能耗现状[J].化工学报,2025,76(4):1375-1390,16.基金项目
国家自然科学基金项目(52376011) （52376011）
中国石油集团科技项目(2022DJ6607) （2022DJ6607）
