1. Introduction to activated sludge method
The activated sludge process is the most widely used aerobic biochemical treatment technology for wastewater, which is mainly composed of aeration tanks, secondary sedimentation tanks, aeration systems and sludge return systems.
2. Characteristics of activated sludge process
The process is relatively mature, with accumulated operating experience and stable operation; the removal efficiency of organic matter is high, and the removal rate of BOD5 is usually 90% to 95%; the aeration tank has a low impact load resistance; it is suitable for treating the influent water with relatively stable quality. Large-scale urban sewage treatment plants with high requirements.
The aerobic and oxygen supply spear is large, the oxygen supply at the head end of the tank is insufficient, and the oxygen supply at the end of the tank is greater than the oxygen demand, resulting in waste; The traditional activated sludge method aeration tank has a long residence time, and the aeration tank has a large volume and a large area. The cost of infrastructure is high and the power consumption is large; The efficiency of deoxidation and phosphorus removal is low, usually only 10% to 30%.