BIOLOGICAL WASTEWATER TREATMENT SYSTEM AND METHOD FOR OXIDATION DECOMPOSING WASTEWATER BY THE SELF-PURIFICATION PRINCIPLE OR USING AEROBIC AND ANAEROBIC MICROORGANISMS OR OTHER MICROORGANISMS

摘要

PURPOSE: To provide wastewater treatment system and method for reducing wastewater treatment time and efficiently removing eutrophication materials such as phosphorous and nitrogen contained in wastewater by oxidation decomposing wastewater using aerobic and anaerobic microorganisms or other microorganisms. CONSTITUTION: An advanced wastewater treatment system comprises: a sedimentation separation tank(12) for settling wastewater flown in to separate sediment from wastewater; a flow equalization tank(13) for temporarily storing intermediate water of the sedimentation separation tank to supply a certain amount of treated water to a first aeration tank(14) that is a front aeration tank by a pump(P1); a second aeration tank(15) and an anoxic tank(16) continuously installed next to the first aeration tank; a third aeration tank(17) and a fourth aeration tank(18) that are rear aeration tanks installed in rear of the anoxic tank; a sedimentation tank(19), a stabilization tank(20) and a disinfection and discharge tank(21) installed in rear of the third aeration tank and the fourth aeration tank; a denitrification tank(22) connected to the return pipe connected to the sedimentation tank; a contact filter medium filling-up part which is installed in the front and rear aeration tanks, and which is vertically divided into upper and lower parts by a mesh net such that contact media(42) are stacked in the upper part of the contact filter medium filling-up part, and a sludge stacking part is formed in the lower part thereof; a diffuser installed in the contact filter medium filling-up part; a return pipe(31) installed in the sludge stacking part and connected to a backwashing pipe and the sedimentation separation tank; a transfer pipe(32) installed at the anoxic tank to transfer treated water to the first aeration tank by a pump; and a treated water transfer pipe(33) connected to the flow equalization tank to transfer treated water to the anoxic tank by a pump(P2).