Membrane Contactor For The Separation Of Carbon Dioxide In The Mixture

Membrane contactor made of hollow fiber polypropylene membrane (HFPPM) was used as separator. The absorbent was the aqueous solution of N-methyldie'thanolam.ine (MDEA) . Mass-transfer performance of separating CO2 from CO2/ N2 was studied in HFPPM contactor. The effects of various factors, including concentration of absorbent and feeding gas, temperature of operation, flow velocity of absorbent and feeding gas, lumen/shell side processes, and differences of membrane modules and membrane configuration on the CO2 absorption efficiency were investigated, operation stability of HFPPM contactor was experimented initially, the value of the overall mass transfer coefficient KG of absorption of CO2 was predicted by mathematical model of kinetics of mass transfer. The result shows that under the conditions of 2.5 mol/L of MDEA concentration, the range of 0.05 L/min ~0.3 L/min of gas flow-rate , the range of 30 mL/min -150 mL/min of liquid flow-rate and the rang of 5%~20% of concentration of gas mixtures, the removal efficiency of CO2 absorption are about 80%~98% and the overall mass transfer coefficient KG2 about 0.01s-1 0.035s-1; the KG value of calculation was better accordant with experimental value. Meanwhile, the characteristics of separation of CO2 by membrane contactor are of quicker mass transfer velocity and higher efficiency of separation.