Volatile methyl siloxane separation from biogas using hollow fiber membrane contactor with polyethylene glycol dimethyl ether: A numerical and experimental study

Abstract

In this study, a mass transfer model for hollow fiber membrane contactors (HFMC) was developed to theoretically investigate the mass transfer performance of volatile methyl siloxane (VMS) separation by HFMC. In addition, the effects of operating parameters such as filling rate, liquid and gas velocities on the effectiveness of HFMC separation of VMS were experimentally investigated. The experimental results showed that the increase of filler fraction improved the removal of siloxane. When the absorbent velocity was 250 mL/min and the gas velocity was 500 mL/min, the removal rates of L2, D4, and D5 were 74%, 92%, and 89%, respectively. Additionally, the fluxes of L2, D4 and D5 also increased with the increase of gas and liquid velocities, which were in good agreement with the calculated results of the mass transfer model. The faster the gas and liquid velocities, the higher the total mass transfer coefficient, which indicated that the mass transfer resistance was reduced in the contactor system. The liquid phase mass transfer resistance contributed the most to the total mass transfer resistance in the non-wetting model. However, when the membrane was 10% wetted, the mass transfer resistance contribution of the membrane increased sharply, reaching a maximum of 38.2%.