| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method for stably keeping high efficient methane fermentation treatment for a long period of time. <P>SOLUTION: Organic solid waste C containing lightweight foreign matter M is supplied into an anaerobic raw material tank 10 provided with a movable rake 60 and a screw conveyer 70 penetrating a peripheral wall at predetermined heights on the inside. The liquid level is kept at a predetermined height by feeding a fermentation solution S to the raw material tank 10, drawing out the fermentation solution S from a lower part and returning it to an upper side. The waste C supplied into the raw material tank 10 is dipped in the fermentation solution S for solubilization and circulated with the fermentation solution S and decomposed into biogas G. The lightweight foreign matter M floating on the surface of the liquid of the raw material tank 10 is collected to the screw conveyer 70 by the movement of the rake 60 and discharged. Preferably, the fermentation solution S stored in a fermentation tank 30 is continuously fed to the raw material tank 10, the fermentation solution S of the raw material tank 10 is continuously drawn out to be separated into solid and liquid. The separated filtrate D is transferred to the fermentation tank 30, and the solid content E is returned to the raw material tank 10 for circulation. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
