NOVELTY - Methane-fermentation of biomass fractionated from collected garbage, is carried out and biogas containing methane gas is desulfurized. The combustible trash from which biomass is removed, is incinerated using an incinerator (2). The temperature of waste gas sent from the incinerator is lowered by a gas-cooling tower (3). The digestive liquid generated from the methane-fermentation tank (12) is transferred to the gas-cooling tower, and thermal decomposition is carried out at 800 degrees C or more.    USE - Recycling of garbage, such as livestock farming waste material (livestock excrement), green farm waste material, organic refuse, agricultural waste material, fishery waste material, food-processing waste material, and wastewater treatment sludge.    ADVANTAGE - The method enables economical and simultaneous processing of garbage and biomass, and recovery of heat energy, without requiring nitrification-denitrification processing facilities. Ammonia component in digestive liquid is used effectively.    DETAILED DESCRIPTION - Methane-fermentation of biomass fractionated from collected garbage, is carried out in a methane-fermentation tank. Biogas containing methane gas emitted from the methane-fermentation gas is desulfurized in a desulfurizing unit (16). The combustible trash from which biomass is removed, is incinerated using an incinerator. The temperature of waste gas sent from the incinerator is lowered by a gas-cooling tower. The digestive liquid generated from the methane-fermentation tank is transferred to the gas-cooling tower, and thermal decomposition is carried out at 800 degrees C or more. The methane-fermentation tank and desulfurization unit are provided in biomass-resource processor (I). A waste-gas processing facility (5) consisting of the incinerator, and gas-cooling tower are provided in combustible-trash recycling processor (II).    DESCRIPTION OF DRAWING(S) - The drawing shows a flowchart of the garbage recycling method. (Drawing includes non-English language text)    Incinerator (2)    Gas-cooling tower (3)    Heat recovery device (4)    Waste-gas processing facility (5)    Methane-fermentation tank (12)    Dehydrator (13)    Desulfurizing unit (16)