METHOD FOR DESULFURIZING DIGESTION GAS AND DESULFURIZER THEREFOR

PROBLEM TO BE SOLVED: To provide a method for desulfurizing digestion gas and a desulfurizer therefor to dispense with concentration measurement of hydrogen sulfide and oxygen or severe control of supplied oxygen quantity for preventing explosion when removing hydrogen sulfide in the digestion gas, make compact a removing/processing part of hydrogen sulfide, obtain high-purity methane gas even when the digestion gas contains a siloxane compound, and take into consideration the removal rate of H2S and CO2from the digestion gas, the operation costs, and equipment costs. SOLUTION: The device comprises: an absorption tower 4 which separates carbon dioxide and hydrogen sulfide from the digestion gas and purifies methane by contacting the digestion gas and water under a high-pressure state satisfying the range of 0.55-2.0 MPaG; a decompression tank 11 and a stripping tower 12 as separation means for separating the carbon dyoxide and the hydrogen sulfide; and a biological desulfurizer tower 16 which accepts the carbon dioxide and the hydrogen sulfide and air 14 as oxygen-containing gas and has a filler layer 15 to which microbes decomposing hydrogen sulfide adheres. COPYRIGHT: (C)2010,JPO&INPIT