| 摘要 |
<p>PURPOSE:To obtain an effluent of high quality, while facilitating solid-liquid separation, by adding a waste liquid contg. organic suspended substance to a digested liquid obtained by the methane fermentation of a waste liquid contg. organic substance before the treatment of precipitating, and then precipitating said digested liquid. CONSTITUTION:A raw liquid contg. organic substance, e.g. pulp mill waste liquor or night soil, is introduced along a line 4 into a pit 1 for the raw liquid. If chlorine or phosphorus content in the raw liquid is insufficient, a proper nutritive salt is added along a line 5. The waste liquid is transferred along a line 6 to a fermenting tank 2 by a pump 15 for supplying the raw liquid. The fermenting tank 2 is held at 35-37 deg.C for mesophilic fermentation or at 50-53 deg.C for thermophilic fermentation bt steam along a line 8. The fermented waste liquid is transferred along a line 10 to a precipitating tank 3 and then separated into solid matter and a liquid. Hence a waste liquid contg. organic suspended substance (e.g. excess active sludge) is added along a line 11 to the fermented waste liquid before being transferred to the precipitating tank 3.</p> |
