Author(s): Wenhui Huang; Xiaojun Song

Linked Author(s):

Keywords: Direct air capture Absorption tower Absorption efficiency Alkali liquor

Abstract: The massive use of fossil fuels has made the concentration of CO2 in the air continue to rise, resulting in the greenhouse effect and climate warming. In order to reduce the concentration of CO2 in the air, the technology of capturing CO2 directly from the air (DAC) has become a research hotspot, but its capture cost is high. This paper adopts the method of model test to research and develop the CO2 capture counter-flow mechanical ventilation absorption tower. Taking the absorption efficiency of the absorption tower as the starting point, the effects of alkali liquor type, alkali liquor concentration, mass water flow per unit plan area of packing, packing section wind speed, packing type, packing height, spraying depth, etc. on the CO2 absorption efficiency are studied. The results show that the CO2 absorption efficiency of the packing with S wave and sheet spacing of 25 mm is the highest. With the increase of the packing height, the CO2 absorption efficiency gradually increases, and the increase range is smaller and smaller. The CO2 absorption efficiency will increase by about 2% for every 0.1 mol/L increase in the concentration of hydroxide. The CO2 absorption efficiency will increase by about 1% for every 1 m increase in the water spraying depth. When NaOH alkaline solution is used as the absorption solution, the CO2 absorption efficiency is slightly higher than that of KOH alkaline solution. Through the study of DAC technology, the factors affecting the CO2 absorption efficiency and their change rules are obtained, which is conducive to reducing the cost of CO2 absorption tower, and has great significance for the promotion and practical engineering application of DAC technology.

DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p1719-cd

Year: 2023