AERATION TANK OF ORGANIC WASTEWATER AND AERATION TREATMENT APPARATUS USING THE SAME

PROBLEM TO BE SOLVED: To improve the purification efficiency of an aeration treatment apparatus to be used for livestock excretion wastewater, lower the installation cost, and consequently prevent environmental pollution. SOLUTION: An aeration tank 1 for organic wastewater is constituted of an outer tank 1 and an aeration pipe 2 installed uprightly in the outer tank 1. The aeration pipe 2 has suction holes 3 in the circumferential wall in a lower part of the pipe and scattering holes 4 in the circumferential wall of an upper part of the pipe and an aeration head 6 connected with an air supply pipe 5 is built in the in side of a lower part. The object wastewater to be treated which is biologically treated in the outer tank 1 is aerated in the aeration pipe 2 and while being scattered and reduced together with produced bubbles from the scattering holes 4 to the outer tank 1, a part of adhering organic substances are conveyed to a sludge precipitation tank. A plurality of aeration tanks having such a constitution are continuously installed and purified water is obtained by aerating and circulating a supernatant liquid of bubbles, which is at first sent out of the first aeration tank to the next sludge precipitation tank, successively in the rest of the aeration tanks. The resultant purified water can be used as cleaning water for cattle sheds and liquid manure.