| 摘要 |
<p>PURPOSE:To hold the pH of a digestion liquid to a good state, by mounting a return pump for returning the waste liquid from a waste liquid treatment tank by the opening and closing of the lid provided to a charging port or the signal from a pH sensor. CONSTITUTION:When the lid 3 of a charging port is opened, a microswitch 4 is turned ON and a return pump 11 is driven. A waste liquid receives aerobic treatment by the aerator 8 in an aeration tank 9 while the waste liquid, of which the pH is about 8, stored in a sedimentation tank 10 is emitted from the opening part 13 of the charging port 2 through a return pipe 12. The garbage 8 charged in the charging port 2 is smoothly supplied into a fermentation tank 1 along with the waste liquid with pH of about 8. By this method, the lowering in the pH of a digestion liquid is suppressed and the pH of the digestion liquid itself is about 7 and methane fermentation is sustained.</p> |
