SEWAGE TREATMENT METHOD

摘要

PURPOSE: A sewage treatment method is provided which is capable of treating sewage without separate disinfection contact pond (chlorine contact pond) by injecting sodium hypochlorite into an inflow part of final sedimentation pond. CONSTITUTION: In a sewage treatment method comprising a series of processes of removing precipitated suspended solids contained in sewage in an initial sedimentation pond(1), blowing air into the suspended solid removed sewage in an aeration tank(2), and returning the activated sludge removed wastewater to the aeration tank after precipitating activated sludge in a final sedimentation pond(3) in which the aerated sewage flows, the sewage treatment method comprises first supply process of supplying sodium hypochlorite to sewage flown in the final sedimentation pond through first supply pipe(11) from a sodium hypochlorite storage tank(7) to disinfect the aerated sewage; second supply process of supplying sodium hypochlorite to the returned activated sludge through second supply pipe(12) from the sodium hypochlorite storage tank if bulking is generated in the activated sludge returned to the aeration tank; and third supply process of supplying sodium hypochlorite to the recycled water through third supply pipe(13) from the sodium hypochlorite storage tank to disinfect recycled water discharged from the final sedimentation pond through a filter(8).