| 摘要 |
PROBLEM TO BE SOLVED: To provide a biological nitrogen removal method that enables efficient denitrification by anammox bacteria without a significant change in a reactor.SOLUTION: In a method for biological nitrogen removal of ammonia nitrogen-containing waste water having a denitrification process for performing denitrification by contacting the waste water with autotrophic denitrifying microorganisms, when waste water containing ammonia nitrogen and nitrite nitrogen is made to flow in from the bottom of a reactor, in which granules comprising autotrophic denitrifying microorganisms have been formed, and flow upward through the reactor in the denitrification process to remove nitrogen in the waste water using the reactor, treatment is performed so that the granules formed in the reactor move in a circumferential direction with the whole granules being integrated while maintaining the formed granule state in an area from the bottom to at least 1/4-1/2 the height within the reactor.SELECTED DRAWING: Figure 1 |
