晚期渗滤液短程生物脱氮的实现

在SBR反应器中利用游离氨（freeammonia，FA）、游离亚硝酸（freenitrousacid，FNA）对NOB（nitriteoxidizingbacteria，NOB）选择性抑制并耦合实时控制策略处理晚期垃圾渗滤液，成功实现持久稳定的短程生物脱氮，并研究了不同碳氮比及初始PH值对短程生物脱氮的影响。结果表明：通过FA和FNA对NOB的选择性抑制，在线检测反应中PH、DO和ORP数值，利用出现的“氨谷”、“ORP平台”“亚硝酸盐膝”等特征点作为运行操作控制时间点，准确得知反应进程，及时开始下一步操作，获得稳定短程生物脱氮。进水NH4＋-N浓度为108～177．3mg／L（平均值为138．7mg／L）时，亚硝积累率一直稳定达90％左右，乙酸钠为碳源时最佳C、N质量比为3，相对于混合液悬浮固体浓度的反硝化速率的平均值达到19．8mg·g-1·h-1NOx--N，出水NH3＋-N、NO2--N、NO3--N、TN分别小于6、2、1和30mg／L；初始PH值为8．5时，反硝化速率最大，pH介于7．5～8．5间，反硝化速率差异小于7．3％．

Achievement of Short-cut Biological Nitrogen Removal of Mature Landfill Leachate

Stable short-cut nitrification was achieved through the selective inhibition of free ammonia （FA）, free nitrous acid （FNA） on the nitrifying bacteria and a real-time control strategy which used pH, DO and ORP as parameters in an SBR reactor. The effects of C/N ratio and initial pH value on the short-cut biological nitrogen removal were studied. It is found that： when influent NH4 ＋ --N concentration was 108- 177.3 mg/L, the nitrite accumulation rate was around 90%. The reasons for the favorable nitrite accumulation rate were both the inhibition of FA and FNA on the NOB and the real-time control strategy through detecting the ＂ammonia valley＂ and ＂nitrite knee＂ two feature points in pH and ORP profiles, respectively. The optimal C/N ratio was 3 when acetate was used as the carbon source. When the denitrification rate with respect to the concentration of mixed liquor suspended solids was 19.8 mg g-1 h-1 NOx--N, NH4 ＋ --N, NO2- --N, NO3--N, TN of the effluent were less than 6, 2, 1 and 30 mg/L, respectively. When initial pH value was 8.5, the denitrification rate was maximum. However the differences of denitrification rate were small when pH was in the range of 7.5-8.5.