| 摘要 |
<p>PROBLEM TO BE SOLVED: To enhance separation performance such as quality of treated water by adjusting an air feed quantity so as to make dissolved oxygen(DO) in an aeration tank constant in a membrane separation activated sludge method. SOLUTION: In a wastewater cleaning method by which air is fed into the aeration tank 2 and the discharge water is biological treated and floating solids in the aeration tank 2 are separated by a membrane separation device 4, dissolved oxygen concentration in the aeration tank 2 is detected with a detector 83 to adjust the air feed quantity, and then the dissolved oxygen concentration in the aeration tank 2 is held nearly constant at 2-4 mg/liter.</p> |
