碳源对生物滞留系统中硝酸盐异化还原成铵的影响研究

通过构建模拟实验,利用~(15)N同位素示踪技术研究在生物滞留系统中碳源对生物滞留系统中硝酸盐异化还原成铵(DNRA)的影响。结果表明:5个处理组(葡萄糖50,100,150,200,250 mg/L)中NO_3~-发生转化的量分别为41.1%、47.9%、50.7%、56.2%和57.6%。以葡萄糖为碳源,初始浓度为100 mg/L时,DNRA作用效果最显著,~(15)N-NH_4~+含量占初始添加~(15)N的24.7%;初始浓度为250 mg/L时,DNRA作用最弱,~(15)N-NH_4~+含量占初始添加~(15)N的13.7%。反硝化和DNRA作用同时进行,系统中~(15)N-NO_3~-含量的减少均伴随着DNRA过程中间产物~(15)N-NO_2~-含量的积累和最终产物~(15)N-NH+4含量的增加。

EFFECT OF CARBON SOURCE ON DISSIMILATORY NITRATE REDUCTION TO AMMONIUM PROCESS IN BIORETENTION

A simulation experiment is constructed by using 15N isotope tracing technique to research the effect of carbon on dissimilatory nitrate reduction to ammonium process (DNRA) in bioretention.The results suggested that in the five treatment groups adding glucose of 50,100,150,200,250 mg/L as carbon source,the transformation rate of NO3 was 41.1％,47.9％,50.7％,56.2％ and 57.6％,respectively.With initial glucose concentration of 100 mg/L,DNRA was most significant,and the exogenous 15N accounted for 24.7％.With initial concentration of 250 mg/L,DNRA was least significant,and the exogenous 15N accounts for 13.7％.Denitrification and DNRA occurred simultaneously.The reduction of 15N-NO3-content in the system was accompanied by the accumulation of 15N-NO2-in the DNRA process and the increase of 15N-NH4+ content in the final products.