Biological nitrification denitrification treatment method of human waste, etc.

摘要

PROBLEM TO BE SOLVED: To make it possible to adequately control both of a nitrification stroke and denitrification stroke in accordance with a standard by making the time ratio of one batch of both strokes constant with a single tank, admitting sewage during the denitrification stroke and increasing or decreasing an aeration air quantity in such a manner that an oxidation reduction potential inflection point appears before the start of the next nitrification stroke.;SOLUTION: The sewage is admitted into the single nitrification and denitrification tank 1 and is subjected alternately to the nitrification stroke by aeration and the denitrification stroke by agitation. Previously, the nitrification and denitrification strokes of one batch and one cycle are set at about one hour to execute the nitrification stroke for about 15 minutes and the denitrification stroke for about 45. When the sewage is admitted for about 5 minutes from the start, the oxidation reduction potential(ORP) value falls rapidly from about 130 mV to around 0 mV and the ORP inflection point appears before around 5 minutes upon the end of the denitrification after the slowness of the value, then falls to about -200 mV. The ORP value rapidly ascends to near about 130 mV again when the next nitrification stroke starts. The aeration air quantity is increased and decreased in such a manner that the ORP inflection point appears during the time before 5 minutes to just before the start of the nitrification stroke.;COPYRIGHT: (C)2001,JPO