OPERATION METHOD OF SEPTIC TANK

摘要

PROBLEM TO BE SOLVED: To provide an operation method of a septic tank capable of suppressing the initial seeding quantity in an aeration tank corresponding to the reduction in the inflow rate of raw water at a time of initial operation and not bringing about the lowering of treatment capacity in an anaerobic treatment tank positioned on the upstream side. SOLUTION: A circulating mechanism S of water to be treated for returning a part of the water to be treated in an aerobic treatment tank to an anaerobic treatment tank N1 and a flow rate adjusting tank N2 positioned on the upstream side are provided and a part of water to be treated is returned to the flow rate adjusting tank N2 at an initial stage of operation and returned to the anaerobic treatment tank N1 when the amt. of activated sludge in the aerobic treatment tank becomes much.