| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a highly efficient and compact methane fermentation process which can be operated stably for a long term. <P>SOLUTION: In the methane fermentation process, a methane fermentation tank is constituted by arranging a first fermentation tank and a second fermentation tank in series which have respectively a filter bed carrying anaerobic microorganism principally comprising methane bacteria, a slurry prepared by crushing organic waste is fed into the first fermentation tank, liquid to be treated after passing through the filter bed in the first fermentation tank and being methane-fermented is sent to the second fermentation tank, the liquid to be treated is methane-fermented again in the second fermentation tank, resources such as bio-gas are recovered and, at the same time, fermented waste liquid is taken out as digestion liquid. Therein, a gas agitation device is disposed on the first fermentation tank, the output of the gas agitation device is stopped until a prescribed elapse of time from slurry feeding or, by reducing the output, material unfit for fermentation in the slurry is separated by sedimentation and, thereafter, the slurry is fermented while being agitated by increasing the output of the gas agitation device. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
