Patent ID: 7033503

Claim:
A municipal wastewater treatment apparatus comprising: a cyclic aeration reactor ( 2 ) having the wastewater fed continuously for 24 hours, which is aerated cyclically by a timer that is operated at a predetermined time interval to create an Aerobic state, wherein ammonia nitrogen is nitrified by the microorganisms eluted from a microorganism control tank in the Aerobic state, the nitrified nitrate nitrogen is reduced into N 2 gas and removed in an Anoxic state in which oxygen supply is stopped, and phosphorus is eluted in a form of orthophosphate (PO4-P) by phosphorus accumulating organisms (PAOs) which can accumulate phosphorus in a form of polyphosphate (poly-p) within cells of the organisms in an Anaerobic state in which NOx-N concentration in the cyclic aeration reactor reaches zero by denitrification in the Anoxic state; a microorganism control tank ( 5 ) which is equipped in the cyclic aeration reactor and elutes activated microorganisms in the Aerobic state of the cyclic aeration reactor; a continuous aeration reactor ( 3 ), which is aerated by oxygen fed continuously for 24 hours, to further treat some organic materials which are not treated in the cyclic aeration reactor due to the continuous influx; a sedimentation tank ( 4 ) for solid-liquid separation of the microorganisms from the treated water; a sludge return line ( 13 ) for returning sedimented sludge in the sedimentation tank into the cyclic aeration reactor depending on the amount necessary for the microorganism concentration in the cyclic aeration reactor; a waste sludge line ( 14 ) for transferring excess sludge in the sedimentation tank to a sludge storage tank ( 6 ); a sludge storage tank ( 6 ) for discarding the excess of sludge; and a return line ( 13 ) of the sludge storage tank for supplying the supernatant to the cyclic aeration reactor together with the fed wastewater.