CONTROLLER FOR FLOW RATE OF AERATION AIR IN SEWAGE TREATING PLANT

摘要

PURPOSE:To maintain the activity of activated aludge and to treat sewage efficiently by providing operators or measuring devices that simulate the consumption rates of oxygen quickly and accurately and operating the required flow rate of air in an aeration tank. CONSTITUTION:The sewage subjected to primary treatments is flowed together with the return sludge form a final settling basin 4 through a pipeline 2 provided with a flowmeter 1 into an aeration tank 3, where both are mixed. The tank 3 has a dissolved oxygen meter (DO meter) 5 and a sludge concn. meter (MLSS meter) 6 in its inlet part. Air diffusers 7a, 7b are divided to plural pieces of groups in a down ward flow direction. The signals of the DO meter 5 and an airflow meter 9 are inputted to the 1st operator 20, by which the consumption rate of oxygen is calculated. The result is inputted together with the signals of the MLSS meter 6, the flowmeter 1, and a return sludge flowmeter 16 to the 2nd operator 21, by which the concn. of the inflow org. materials is calculated. In a computer 22, the water flows for a few hours - a few days are forecast.