Sewage treatment plant operation method, operation control device, and sewage treatment plant

摘要

PROBLEM TO BE SOLVED: To provide an operation method of a sewage treatment plant, with which a biological treatment can be performed with excellent energy efficiency and further a microbial flora of activated sludge can be guided to a microbial flora predominantly consisting of soil microorganisms within a short time even when the sewage treatment plant has a BOD/SS load lower than a planned value, and to provide an operation control device and the sewage treatment plant.SOLUTION: In an operation method of a sewage treatment plant including: a storage tank to store sewage; a biological treatment tank to biologically treat the sewage stored in the storage tank; a pump device to supply the sewage from the storage tank to the biological treatment tank; and an aerator to aerate the biological treatment tank, the sewage treatment plant is operated such that a first operational state in which the pump device and the aerator are stopped and a second operational state in which the pump device and the aerator are operated are switched between each other in a day, and when a BOD/SS load of inflow sewage is lower than a predetermined BOD/SS load, a second operation time is set such that biological treatment is performed at the predetermined BOD/SS load.