Removal of nitrate by supported autotrophic denitrifiers
- Received Date: 15/02/2009
- Accepted Date: 11/11/2008
-
Key words:
- autotrophic denitrifiers /
- nitrate /
- kinetics
Abstract: In order to find a more effective and economical way to remove nitrate in wastewaters,six kinds of autotrophic denitrifying bacterial strain,which could oxidize elemental sulfur and reduce nitrate,were screened from facultative sludge.The strain N-I was the dominant strain according to the degradation curve of each strain.The environmental factors,including pH,temperature and carbon source,which had great influence on the degradation of strain N-I and the degradation kinetics of nitrate were investigated.Through a series of studies,the removal of nitrate by strain N-I conformed to first order reaction kinetics equation with a half-life of 1.42 hours and rate constant of 0.488 h-1.The optimum reaction conditions were obtained as follows:a neutral pH of 7,30℃ and concentration of sodium bicarbonate greater than or equal to 2.5 g/L.
DownLoad:
