AN IMPROVED WASTE WATER DENITRIFICATION PROCESS

摘要

A waste water treating apparatus for denitrification comprises a reaction tank (103), a separator (105) for separating an activated sludge from the treated water from the reaction tank (103) and a sludge return path (107) for returning the separated activated sludge. NH4-N contained in a waste water being supplied is converted into NOx-N (NO2-X and NO3-N) in the reaction tank (103). In order to maintain the ratio of NO3-N/NOx-N to be less than 0.5, the apparatus is run such that the concentration of NH4-N may be more than 15 ppm and BOD may be more than 30 ppm in the reaction tank (103).