Research on Treatment of NH_3-N Wastewater Using High Efficiency Nitrobacteria

Five strains of nitrobacteria were separated and purified from activated sludge of sewage treatment plants,which were identified as Nitrosomonas sp and Nitrobacter sp,respectively.The environmental factors affecting the nitrification were investigated and the most suitable conditions for the growth of the nitrobacteria were determined.With the addition of the nitrobacteria into the domestic NH3-N sewage and nitrogen fertilizer plant wastwater,the removal rate of NH3-N was 99.5% and 97.4%,respectively,while that for the control was only 82% and 79%.Moreover,continuous and stable NH3-N removal effects could be achieved with only one addition at the initial stage of the experiments.