| 摘要 |
<p>PURPOSE: To provide an efficient biologically nitrifying and denitrifying method at low cost whose constitution of process is simple and which does not need a hydrogen donor or chemicals for adjusting pH. CONSTITUTION: In a method for biologically nitrifying and denitrifying waste water 1 containing nitrogen compounds including ammoniacal nitrogen, the method comprises a partial nitrifying process 2 wherein the waste water 1 is partially nitrified by means of autrophic nitrifying bacteria under aerobic conditions and a bound oxygen denitrifying process 4 wherein, in the presence of a group of autrophic denitrifying bacteria in which bound oxygen can be utilized, the liquid flowing out of the process 2 is denitrified by turning NH4 -N and NO2 -N and/or NO3 -N in the liquid into N2 gas. A pH adjusting process 3 is preferably provided between the process 2 and the process 4 to circulate a part of the treated liquid flowing out of the process 4 to the process 2 and/or the process 3 (6, 7), to adjust pH.</p> |
