富氧生物硝化处理微污染原水除NO_2^- -N研究

Removal of NO_2^- -N in a polluted raw water of water sources by bio-nitrification process of oxygen enrichment

为去除微污染原水中的NO2--N和提高水厂的饮水安全性,采用弹性填料微孔曝气富氧生物硝化法处理某微污染水源原水,探讨了原水不同水质及天然水体温度下富氧生物硝化工艺的除NO2--N效果,研究了水温与富氧生物硝化工艺NO2--N去除效果的相关性。结果表明,当富氧生物硝化工艺正常稳定运行HRT为1.2h,气水比为1∶1,pH6.5~7.4,DO为8~10mg·L–1,原水水温26~30℃、NO2--N0.05~0.4mg·L–1、NH4+-N0.4~1.8mg·L–1和CODMn7.01~9.61mg·L–1时,富氧生物硝化工艺NO2--N的去除率为77%～100%;原水水温20～22℃、NO2--N0.09~0.5mg·L–1、NH4+-N0.7~2.5mg·L–1和CODMn5.84~9.11mg·L–1时,去除率为44%～63%;原水水温10～12℃、NO2--N0.04~0.8mg·L–1、NH4+-N0.9~4.5mg·L–1·和CODMn6.53~9.27mg·L–1时,去除率为25%～40%。原水水温与富氧生物硝化工艺NO2--N去除率呈现明显的线性相关性,相关方程为:y=3.3628x-9.528,相关系数为0.8744。

NO2^--N removal in a polluted raw water of water sources by the bio-nitrification process of oxygen enrichment with the elastic fillings and micro-pore aerators of membrane piece has been studied under the different conditions of raw water in order to increase the safety property of drinking water. The correlation between water-body temperature and the NO2^--N removal in the pol- luted water sources has been discussed according to the experimental results. The research results show the bio-nitrification process of oxygen enrichment can reach a removal efficiency of 77%-100% for NO2^--N of water sources with ordinary temperature 26-30℃,NO2^--N 0.05-0.4 mg·L^-1, NH4^＋-N 0.4-1.8 mg·L^-1 and CODMn7.01-9.61 mg·L^-1 in the water sources , a removal efficiency of 44%-63% for NO2^--N of water sources with the temperature 20- 22 ℃, NO2^--N 0.09-0.5 mg·L^-1, NH4^＋-N 0.7-2.5 mg·L^-1 and CODMn5.84-9.11 mg·L^-1 ,and a removal efficiency of 25%-40% for NO2^--N of water sources with the temperature 10- 12 %, NO2^--N 0.04-0.8 mgL, NH4^＋-N 0.9-4.5 mg·L^-1＇and CODMn 6.53-9.27 mg·L^-1 in the water sources under the conditions of the running parameters HRT 1,2 h, pH 6.5-7.4, gas and water ratio 1 ： 1 and DO 8-10 mg-Lt for the biofilm process, A good linear correlation is existed between water-body temperature and the removal efficiency of NO2^--N. The correlative equation is expressed as y=3.362 8x - 9,528 and its correlative coefficient is 0.874 4.