pH和DO作为A_2N-IC-SBR工艺实时控制参数

Study on DO and pH as on-line control parameters in A_2N-IC-SBR process

试验从硝化污泥和聚磷污泥的培养开始至A2N-IC-SBR工艺稳定运行结束,系统地记录了污泥驯化培养阶段、A2N工艺运行阶段、A2N-IC工艺运行阶段中pH和DO的变化与氮磷浓度的关系.结果表明:厌氧阶段pH的变化比较复杂,与进水碳磷比、反硝化聚磷菌和好氧聚磷菌的富集程度等因素有关,不同的进水水质与污泥有不同的变化规律;诱导结晶阶段pH的变化受到钙盐投药方式以及混合方式的影响,pH与SP浓度的变化并不存在明显的相关性;硝化反应中硝化作用完成的特征点较明显,d(DO)/dt最大值点及d(pH)/dt由负变正的特征点均可作为硝化完成的指示点;好氧聚磷阶段,聚磷终点与pH拐点、DO大幅上升出现的时刻相同;缺氧聚磷阶段,pH停止上升的时刻可以用来指示聚磷的完成.

From the phosphorus removal sludge and nitrogen removal sludge cultivation period to the steady operation period of A2N-IC-SBR（anaerobic/anoxic/nitration-induced crystallization-sequencing batch reactor,A2N-IC-SBR）process,the relationships between pH/DO and nutrient concentrations were investigated systematically,including sludge cultivation stage,A2 N process operation stage and A2N-IC process operation stage.The results indicate that in the anaerobic stage,pH profile is complicated.It is related to the influent C/P ratio,enrichment of denitrifying polyphosphate accumulating organisms and phosphorus accumulating organisms.With different sludge characteristics and influent wastewater compositions,it shows different variations.During the IC（induced crystallization）stage, the dosage modes and mixture approaches affect the pH variations.SP has no obvious correlation with pH.Under the nitrification stage,the feature points for nitrification ending are apparent.The maximum value of d（DO）/dt and the point of d（pH）/dt from negative to positive can both be the feature points for indicating the end of nitrification.In the aerobic phosphorus removal stage,the inflexion point of pH,the sharp rise point of DO and the end of phosphorus removal appear at the same time. An inflexion point of pH is observed when the denitrifying phosphorus removal is finished.