| 摘要 |
PROBLEM TO BE SOLVED: To more stably remove nitrogen against fluctuation of water quality and flow rate of inflow non-treated water while reducing cost required for water treatment by reducing power required for sewage treatment.SOLUTION: In a water treatment apparatus, a first aerobic tank 1 into which raw water flows, an anoxic tank 2, a second aerobic tank 3, and a final sedimentation basin 4 are connected in series. The inside of the first aerobic tank 1 is aerated by air volume-controllable first aeration means 5, and the inside of the second aerobic tank 3 is aerated by second aeration means 7. Outflow water from the second aerobic tank 3 is led to the final sedimentation basin 4 without being returned to the anoxic tank 2 and the first aerobic tank 1. The organic matter concentration of the raw water is measured by organic matter concentration measuring means 10, and the nitrogen concentration of the raw water is measured by nitrogen concentration measuring means 11. Nitrification rate setting means calculates the optimum nitrification rate from the organic matter concentration and nitrogen concentration of the raw water detected by the organic matter concentration measuring means and the nitrogen concentration measuring means. First aeration control means 14 controls the air volume of the first aeration means 5 according to the calculation result of the nitrification rate setting means. |
