Purification of methane in methane-carbon dioxide gas mixture by the membrane method

Carbon dioxide, hydrogen sulfur and water vapor which are energy diluting components must be separated from biogas in order to storage, transport and use in vehicles as fuel. Membrane separation technique has an increasing importance in last decades compared to conventional techniques for the separation of carbon dioxide which has the highest percentage between those chemicals in biogas. Despite low energy consumption of membrane processes, they can perform at low temperature and gas flow rates, and can be preferred because of their modularity and simplicity in applied areas. In this study, hydrophobic, porous polysulphone membrane was used for the separation of CO2 in biogas. CO2 was absorbed into water and calcium hydroxide solution through the porous membrane. The removal efficiency of CO2 was investigated at different gas and liquid flow rates. The results obtained showed that CO2 removal efficiency was increased by the increase of liquid flow rates and by decrease of gas flow rates. The maximum CO2 removal was obtained at a gas flow rate of 122,5 ml/min and a liquid flow rate of 1000 ml/min and water was used as absorbing liquid Keywords: Methane - Carbondioxide, Gas Separation, Membrane Method , Purification of Methane