Method and apparatus for composting organic matters having high water content

摘要

It is intended to provide a method and apparatus for composting a garbage and the like having a high water content by having it efficiently dehydrate, dry and ferment. Organic matters having a high water content is composted by: a fermentation and decomposition step in which organic matters containing a large amount of water is held in a treatment tank under supply of air for not less than one hour and not more than three hours at a temperature from ordinary temperature to not more than 60 DEG C while heating, agitating and grinding them to make them into a rice porridge state and to have it perform aerobic fermentation, and generated gas and water vapor are extracted to the outside of the treatment tank to perform the dehydration and drying thereof into a water content of not more than 65 %; a thermal decomposition step in which a temperature of a fermentation and decomposition product is held for no less than one hour and not more than six hours at not less than 60 DEG C and not more than 100 DEG C to thermally decompose the fermentation and decomposition product, and generated gas and water vapor are extracted to the outside of the treatment tank to perform dehydration and drying thereof into a water content of not more than 45%; and a final drying step in which a temperature of a thermal decomposition product is held for not less than one hour and not more-than six hours at not less than 100 DEG C and not more than 135 DEG C to perform sterilization, and the generated gas and water vapor are extracted to the outside of the treatment tank to perform dehydration and drying thereof into a water content of not more than 30%.