Numerical and Experimental Study on Liquid Film Flows on Packing Elements in Absorbers for Post-combustion CO2 Capture

To reduce global warming and greenhouse gas emissions, it is important to develop Carbon Capture and Storage (CCS) technology, especially for coal fired power plants. Post-Combustion CO2 Capture (PCC) is one of the greatest potential technologies for reducing CO2 emissions, because of its economy and efficiency. Gas-liquid interfacial flows, such as the flue gas and the liquid solvent, are applied to the absorption process. Efficient control of liquid solvent flows by using packings in absorbers can increase the gas-liquid interfacial area and the mass transfer rate. The present study focuses on detailed descriptions of interfacial flows, as well as how such phenomena are affected by wall surface texture treatments. This study develops a numerical simulation technique using Computational Fluid Dynamics (CFD) as well as a lab-scale experimental testing technique. Through the comparison of two geometry cases (smooth wall and wavy wall), the numerical and experimental results show that surface texture treatments can help to prevent the liquid channeling and can increase the wetted area. Furthermore, our advanced design of surface texture treatments and packing systems is developed. The absorption column tests using the CO2-NaOH system show that our advanced packings have lower gas pressure loss and higher absorption performance by comparing to several conventional structured packings.