溶解氧和温度对半量亚硝化的影响研究

Effects of Dissolved Oxygen and Temperature on Half-Nitrification

为探究低氨氮负荷条件下,溶解氧(DO)和温度对实现半量亚硝化的影响。本实验选择序批式活性污泥反应器(SBR),通过改变SBR反应器运行方式,不断降低DO浓度,结果表明,曝气时DO在0.5～0.8 mg/L搅拌时ORP在54～80 mv实现半量亚硝化,NO2--N/NH4+-N/比值为1.0～1.2。最适温度在25～30℃,温度降低到20℃半量亚硝化被破坏。混合液中微生物产生胞外聚合物(EPS)中的多糖(PS)和蛋白质(PN)先增加后减少,不同阶段总氮(TN)的减少可能与之相关。

In order to investigate the effects of dissolved oxygen(DO) and temperature on the realization of half-nitrification under low ammonia-nitrogen loading conditions. A sequencing batch reactor(SBR) was used to study the nitrogen change process under the condition of decreasing the dissolved oxygen concentrations. The experimental results indicated that the stable partial nitrification is achieved successfully when the DO is 0.5~0.8 mg/L in aeration and the ORP is 54~80 mv in aeration. The ratio of nitrite nitrogen to ammonia nitrogen is 1.0~1.2. The optimum temperature is 25~30 ℃, the temperature is reduced to 20 ℃, and the half-nitrification is destroyed. Moreover, the results showed that the polysaccharides(PS) and protein(PN) in the extracellular polymer(EPS) produced by microorganisms in the mixed solution increase initially and decrease afterwards. The decrease of total nitrogen(TN) in different stages may be related to it.