盐度对活性污泥驯化前后硝化特性的影响

通过批量试验系统研究了盐度对常规活性污泥硝化作用的影响以及污泥在含盐环境中经过驯化后其硝化功能的变化.试验结果表明,硝化菌比亚硝化菌对盐度更敏感,废水中含盐浓度为5 g/L时,对常规活性污泥中的亚硝化菌影响不大,硝化菌会受到一定程度的抑制;当含盐浓度超过10 g/L时,硝化菌和亚硝化菌均会受到严重抑制;含盐浓度大于30 g/L时,亚硝化菌和硝化菌已经完全受到抑制.在污泥驯化初期,耐盐硝化菌群数量较少,比硝化速率较低,硝化产物中亚硝态氮大量积累;随着驯化时间的延长,耐盐硝化菌群数量增加,比硝化速率增加,亚硝态氮累积量减少.污泥经过驯化后,硝化菌群可以逐渐适应高盐环境,在含盐浓度为30 g/L时硝化反应仍能进行.

Effects of salinity on the nitrification of activated sludge before and after acclimation

The effects of salinity on the nitrification of activated sludge without acclimation and with acclimation were studied respectively on the basis of batch experiments. In this study, it was found that nitrobacteria were more sensitive to salinity than nitrosomonas. For the activated sludge without acclimation, nitrosomonas were hardly inhibited and nitrobacteria were inhibited at saline content of 5 g/L. While they were both severely inhibited at 10 g/L and completely inhibited at 30 g/L. For the sludge acclimated in saline wastewater, the specific nitrification rate was lower and NO^-₂-N accumulates greatly in the initial phase of acclimation because of few halo-tolerant bacteria and the sensitivity of nitrobacteria to salinity. However, nitrosomonas increased and the specific nitrification rate increased as the acclimation time became longer, the nitrobacteria also increased to enough number to oxidize NO^-₂-N to NO^-₃-N rapidly. The nitrobacteria flora after acclimation could still be active at saline content of 30 g/L.