| 摘要 |
The present invention provides an apparatus for purifying wastewater comprising: an anaerobic tank (1) for treating the wastewater with anaerobic bacteria; an anoxic tank (2) for treating the wastewater from the anaerobic tank (1) with denitrifying bacteria and then returning part of the wastewater to the anaerobic tank (1); an aerobic tank (3) for treating the wastewater from the anoxic tank (2) with aerobic bacteria and then returning part of the wastewater to the anoxic tank (2); and a clarifier (5) for settling the wastewater from the aerobic tank (3), discharging a purified water, and returning part of a sediment to the aerobic tank (3) through a return line (6). Besides, the present invention provides an apparatus for purifying wastewater, which has an anaerobic tank, an anoxic tank, an aerobic tank, and a clarifier, comprising a dissolved oxygen lowering tank for receiving the wastewater returned from the aerobic tank positioned after the anoxic tank and part of the wastewater from a zone positioned before the anoxic tank to decrease the dissolved oxygen, and then introducing the received wastewaters into the anoxic tank. |
