Preliminary experimental study on the performance of CO2 capture prototype based on temperature swing adsorption (TSA)

Abstract

Capturing CO2 from the post-combustion flue gas through temperature swing adsorption (TSA) has been considered as an effective solution to reduce carbon emissions. However, in the fixed bed field, the vast majority of the existing experimental studies are bench-scale. In this study, a fixed bed double-column TSA prototype with treatment capacity of 2.4 m3/h flue gas is designed and developed. The influence from parameters, such as desorption duration, adsorption temperature, desorption temperature, CO2 concentration, heat recovery duration and vacuum duration, are analyzed, to the prototype performance, based on the preliminary experiment data. The performance indicators include purity, recovery ratio, productivity, specific energy consumption, coefficient of performance of CO2 capture and exergy efficiency. The prototype performance in single- and double-column modes are compared as well. The results of double-column mode show that decrease of adsorption temperature (from 293 K to 278 K), increase of desorption temperature (from 353 K to 373 K) and CO2 concentration (from 13% to 19%) lead to an improvement of the prototype performance, the maximum purity, recovery and productivity are 98.13%, 81.30% and 25.22 kg/(ton·h), respectively. The maximum coefficient of performance of CO2 capture and exergy efficiency are 2.46 and 17.67%, respectively. Extending the desorption time is conducive to the improvement of the prototype performance, however, a long operation time would be meaningless to improve performance. With the addition of heat recovery, exergy efficiency increases from 12.30% to 12.89%. At the same time, the productivity of double-column is 2.24 times higher than that of single-column.