Biofilm reactor and biogas purification method thereof

The invention relates to the technical field of biological purification, and mainly discloses a bio-membrane reactor and a biogas purification method thereof.The bio-membrane reactor comprises a liquid storage tank and a reactor body, a filter material capable of being attached with a bio-membrane is arranged in the reactor body, and the two ends of the reactor body are communicated with the bottom and the top of the liquid storage tank; the reactor main body is further communicated with the air inlet, sludge subjected to anaerobic digestion is filtered and then mixed with a nutrient solution, the mixture is circularly introduced into the reactor main body at a certain rate, so that a biological membrane is attached, hydrogen and carbon dioxide are continuously introduced, and by limiting the reactor main body with a certain length-diameter ratio and utilizing the adhesiveness of water, the biological membrane is formed. According to the present invention, the energy conversion loss of the reactor main body c