Aeration

Sewage treatment system of small communities requires the easy maintenance control. In addition, for large fluctuation in the influent load, the stable treatment performance is obtained, and further as there are many cases that the water-intake is made for the city and agricultural water in the downstream of the river where the effluent is discharged, the high removal performance is also required for the nutrients like nitrogen and phosphorus. Under such a background, the intermittent aeration system with single reactor (generally called the two-beat system) was developed. The intermittent aeration system with single reactor (the intermittent aeration system for short) is that, a submerged mechanical aerator for both anoxic and aerobic treatment is installed in a reactor of complete mixing type.