反硝化过程中亚硝酸盐积累研究

在一个SBR反应器中研究了反硝化过程中的亚硝酸盐积累现象。在低的pH和低C/N比(3和2.5)条件下有较明显的积累。pH为5.8左右有利于反硝化过程的亚硝酸盐积累。C/N比为3时,获得的亚硝酸盐积累率最大可达45%。虽然C/N比为2.5时的亚硝酸盐积累率降为37%,但其碳源药剂费用少,并且其出水COD浓度低,可减少后续处理费用。在C/N比为2.5时,硝酸盐降解速率、亚硝酸盐积累速率和亚硝酸盐降解速率随着初始硝酸盐浓度的增大而增大,最高分别达60.02、36.27、10.376 mg.N/(L.h)。而硝酸盐初始浓度40 mg.N/L以上时,对亚硝酸盐的积累率影响不大,为47.5%左右。

Nitrite Accumulation during the Denitrification Process

The nitrite accumulation in the denitrification process is investigated with a sequencing batch reactor（SBR）,and nitrite accumulates obviously at different C/N ratios（3 and 2.5） and low pH.And pH 5.8 is advantageous to the nitrite accumulation during the denification.The max nitrite accumulation ratio is 45% when C/N ratio is 3.Although a lower accumulation ratio（37%） is obtained at 2.5 of C/N ratio,costs of medicament and succedent disposal can be economized and the COD concentration in effluence will be lower.At C/N ratio 2.5,the rate of nitrate reduction,nitrite accumulation and nitrite reduction increases with the rise of the initial nitrate concentration,reaching the maximum of 60.02、36.27、10.376 mg·N/（L·h）,respectively.The nitrite accumulation ratio presents no significant change（about 47.5%） when the initial nitrate concentration is above 40 mg·N/L.