PRETREATMENT METHOD FOR ORGANIC RESIDUE IN METHANE FERMENTATION SYSTEM

摘要

PPROBLEM TO BE SOLVED: To provide a method for reliably and efficiently performing sterilization and a method for efficiently performing methane production in a methane fermentation system in which methane fermentation is performed by using organic residue such as livestock excreta and garbage as the starting material, biogas produced thereby is utilized as fuel of a cogeneration system, a boiler, etc., and digestion liquid after fermentation is utilized as liquid manure. PSOLUTION: In the pretreatment method for organic residue, the organic residue is ground, thereafter, is charged into a heating part and is stirred therein and, at the same time, steam is supplied and, thereby, the temperature of the organic residue is elevated to a heat sterilization temperature of the high temperature side. Subsequently, the temperature-elevated organic residue and domestic animal excreta are charged to a mixed sterilization part and are mixed and thereby, the temperature of the mixture is adjusted to become a heat sterilization temperature of the low temperature side and is maintained for a predetermined time. Subsequently, the indirect heat exchange with the domestic animal excreta is performed in a heat exchange part, thereby, the temperature is adjusted to that suitable for the fermentation. Thereafter, the domestic animal excreta is charged into a methane fermentation vessel and the domestic animal excreta which is preheated by the indirect heat exchange is charged into the mixed sterilization part. PCOPYRIGHT: (C)2004,JPO&NCIPI