| 摘要 |
<p>PURPOSE:To suppress the generation of methane and carbon dioxide in a settling tank and to improve the capacity and speed of settling and sepn. by adding and mixing cold water to and with the digesting liquid from a high temp. methane fermentation tank prior to feeding said liquid to the settling tank. CONSTITUTION:Raw waste liquid such as waste plup liquid, night soil or the like is fed into a high temp. methane fermentation tank 1, where the liquid is subjected to a fermentation treatment. Cold water is added and mixed to and with the resulted digesting liquid to apply thermal shock thereto. The cold water in this case is added by regulating a control valve 4 suitably with a temp. controller 3 in such a way that the digesting liquid attains a prescribed liquid temp. The liquid is then deaerated of entrained gases in a deaeration tank 5, thereafter the liquid is fed into a settling tank 2. The deposited sludge 6 formed in the tank 2 is discharged with a pump 7, and is partly returned into the tank 1. The rest is subjected to a dehydration treatment.</p> |
