pH对以亚硝酸盐为电子受体反硝化除磷的影响

Influence of pH on denitrifying phosphorus removal using nitrite as electron acceptor

利用驯化成功的反硝化聚磷污泥以SBR进行试验,研究pH对反硝化除磷的影响,比较不同pH下厌氧释磷过程中主要储能物质的变化,探讨产生不同除磷效果的原因,考察典型周期内系统的运行效果。研究结果表明:除磷效果与pH(pH=6～8)成正相关,当pH为8时,颗粒污泥最大比厌氧释磷速率和最大比缺氧吸磷速率分别为20.95 mg/(g.h)和23.29 mg/(g.h);厌氧段聚羟基丁酸(PHB)质量分数升高到62.87 mg/g,出水TP质量浓度为1.47mg/L;随着pH升高,厌氧反应吸收的乙酸、合成的PHB质量分数都随之升高,乙酸的吸收率和聚磷分解率变化趋势较相近;当pH超过8后,易形成磷沉淀,除磷率下降。

A series of experiments using denitrifying phosphorus accumulating sludge cultivated in A/A process were carried out in SBR. The effect ofpH on denitrifying phosphorus removal was studied. Variations of the main intracellular polymer during a cycle were compared to discuss the probable reasons for different performances of phosphorus removal and operation effect in typical cycle was investigated. The results show that pH （pH=6-8） is proportional to phosphorus removal rate. When pH is 8, the maximum specific phosphorus release rate and the maximum specific phosphorus uptake rate are 20.95 mg/（g.h） and 23.29 mg/（g＇h）, respectively. The mass fraction of PHB increases to 62.87 mg/g under anaerobic condition, and the effluent mass concentration of TP is 1.47 mg/L. With the increase of pH, the mass fractions of acetic acid and PHB increase, and the changes of absorptivity of acetic acid and disintegration rate of poly phosphorus have the similar trend. When pH is over 8, the precipitated phosphate is generated easily, and the phosphorus removal rate decreases.