At present, there are three kinds of biogas purification methods, namely chemical absorption, physical purification and biological removal. The degree of biogas purification depends on the use of biogas. Methane heating needs to remove H2S and H2O; biogas power generation needs to remove H2S, H2O and organic halides; biogas is used as automobile fuel to remove H2S, H2O, organic halides and CO2; when biogas is integrated into the natural gas network, it needs to remove H2S, H2O, organic halides, CO2 and metals.
