METHANE FERMENTATION DEVICE USING BIOMASS AS RAW MATERIAL AND METHOD OF CONTROLLING TEMPERATURE OF METHANE FERMENTATION VESSEL

PROBLEM TO BE SOLVED: To develop a methane fermentation device in which adaptation to the change in livestock scale and repair are relatively easily performed and in which introduction and maintenance costs are relatively low.SOLUTION: The methane fermentation device uses a gas holder in a purification mechanism. The gas holder includes a recessed container filled with purification liquid and a recessed floating lid floating on the purification liquid in the recessed container. In the gas holder, a purification space is formed between the purified liquid in the recessed container and the recessed floating lid. By simplifying a purification mechanism, the methane fermentation device which can easily deal with reduction in introduction and maintenance costs and repair is achieved. The methane fermentation device is further provided with a solar water heater, and maintenance costs are further reduced by performing temperature control by temperature change management.