METHOD FOR REMOVING CARBON DIOXIDE FROM MIXED GAS AND ALTERNATIVE NATURAL GAS GENERATING DEVICE USING THE METHOD

摘要

A method for removing carbon dioxide from mixed gas containing methane and carbon dioxide by using a plurality of adsorption tanks filled with CMS through the PSA method. The PSA method includes at least adsorption, desorption and pressurizing steps. The method of the invention is characterized in that an initial stage of the desorption step is a recycling stage in which 20 to 40 % of the whole desorbed gas is recycled to material gas. The pressure in the adsorption step is preferably set to 5 kg/cm<2>G or higher to less than 10 kg/cm<2>G, and the final pressure in the desorption step is preferably set to 100 Torr to 20 Torr. The invention method is preferably incorporated in an alternative natural gas generating process.