METHOD AND DEVICE FOR WASTE WATER TREATMENT

摘要

PURPOSE:To increase the treating capacity for waste water and to reduce the size of installations by forming denitrification and reduction regions of low concns. of dissolved oxygen in the upper part of an ascending flow passage of a circulation system formed with a long descending flow passage and an ascending flow passage in a vertical direction. CONSTITUTION:A supply pipe 11 for raw waste water is inserted and opened into the upper half part of an ascending flow passage 4 and the raw waste water flowing in from here is mixed with the circulating waste water ascending in the passage 4. In accordance with this flow the waste water is circulated. A reduction region X to waste water is formed in the part upper than the opening part of the pipe 11. An outflow pipe 12 for flowing out the waste water treated in the circulation system is inserted into the passage 4, and its leading end part is opened below by at least >=50cm from the opening part at the leading end of the pipe 11, so that part of the treated waste water prior to the mixing of the raw waste water is flowed to the outside of the circulation system.