Nutrient salt treatment system for advanced treatment of sewage and wastewater

PURPOSE: Provided is a nutrient salt treatment system which is capable of effectively removing nitrogen and phosphorous by ensuring optimum hydraulic retention time which is accomplished by stream modification. CONSTITUTION: The system comprises an anaerobic tank(1) for removing phosphorous contained in introduced wastewater and transferring the phosphorous-treated wastewater to an anoxic or intermittently aeration reactor(2), the anoxic or intermittently aeration tank(2) for removing nitrogen in the introduced wastewater and transferring the nitrogen-treated water to a clarifier(4), the clarifier(4) for separating the treated water into effluent water and sludge, and a flow alternator(5) for controlling discharge and return of the effluent water, in which the flow alternator(5) returns the effluent water to the anaerobic tank(1) after hydraulic retention time.