氨氮污泥负荷及DO对高浓度亚硝化系统的影响

The effects of nitrogen sludge load and DO on high concentration nitrous nitrifying system

通过氨氮污泥负荷影响试验和DO影响试验数据分析,得出以下结论:1)高浓度亚硝化系统氨氮降解率及亚硝化率均随着NH4+-N污泥负荷的增高而下降。HRT<2d系统随NH4+-N污泥负荷增加,氨氮降解率迅速下跌到25%～29%;HRT≥2d系统随NH4+-N污泥负荷增加,氨氮降解率缓慢下降到50%～60%;HRT=2.5d和HRT=3d的系统中亚硝化率随NH4+-N污泥负荷增加而下降的趋势不甚明显;HRT=5d系统中亚硝化率的下降是由于污泥产生适应性的造成。因此高浓度亚硝化反应系统的NH4+-N污泥负荷不宜过高。2)随着DO的升高,高浓度亚硝化系统的氨氮降解率一直逐步升高。DO<0.7mg/L是不利于氨氮降解的;DO>2mg/L时氧化的NH4+-N都转变成了增加的NO3--N,亚硝化率下降。将DO控制在0.7～1.3mg/L之内可保证较佳的NH4+-N降解率和亚硝化率。

The purpose of this paper is to investigate the impact of nitrogen sludge load and dissolved oxygen（DO） on nitrite nitrification system. The following conclusions have been drawn based on the experimental data and analysis results： 1） The ammonium degradation rate and the nitrous accumulation rate of high concentration nitrous nitrifying system decline with the increase of NH/-N sludge load. When HRT is less than two days, the ammonium degradation rate rapidly declines to 25 %- 29 % with the increase of NH2-N sludge load. When HRT is beyond two days, the ammonium rate of the system slowly falls to 50%- 60% with the NHT-N sludge load increased. When HRT is 2.5 days or 3 days, the declined trend of the system nitrous accumulation rate is not obvious with the NH4＋-N sludge load increased. When HRT is 5 days, the decrease of nitrous accumulation rate is caused by the adaptation of sludge. So the NH4＋-N sludge load of high concentration nitrous accumulation system should not be too high; 2）With the increase of DO, the ammonium degradation of high concentration nitrous nitrifying system is gradually increased. When the DO is less than 0.7 mg/L, it is not conductive to the ammonium degradation. When the DO is higher than 2 mg/L, the oxide of NH4＋-N is changed into the increased of NO3-N and the nitrous accumulation rate declined. If tile concentration of DO is controlled within 0. 7to 1.3 mg/L, the high concentration nitrous nitrifying system can have a good NH4＋ - N degradation rate and nitrous accumulation rate.