Hydrogen / methane fermentation method and system

摘要

PPROBLEM TO BE SOLVED: To enable stabilizing and improving the efficiency of hydrogen fermentation and methane fermentation of biomass without using an alkali agent for pH adjustment, and to obtain a high nutrient salts removal capacity. PSOLUTION: A hydrogen-methane fermentation method has a process for generating hydrogen gas by hydrogen fermentation of biomass raw materials, a process for generating methane gas by methane fermentation of slurry after the hydrogen fermentation process, a process for digesting and denitrifying the slurry after the methane fermentation process, and a process for supplying sludge, separated from the slurry after the denitrification process, to the hydrogen fermentation. It is preferable that a supernatant liquid to be separated solid-liquid in the denitrification process is biologically nitrified and the treated water is supplied to the denitrification process. It is preferable that a carrier in which nitrifying bacteria are inclusively immobilized is brought into contact with the supernatant liquid in the denitrification process. It is preferable that the sludge separated from the slurry after the denitrification process is supplied to the hydrogen fermentation so as to adjust the alkalinity to 7,000-9,000 mg CaCOSB3/SB/L. PCOPYRIGHT: (C)2011,JPO&INPIT