pH对低温除磷微生物种群与聚磷菌代谢的影响

在5°C条件下通过运行SBR生物除磷反应器和静态实验考察pH对低温生物除磷系统的影响。pH不仅影响生物除磷反应器的性能,而且也会影响生物除磷系统的微生物种群结构。在pH为6的条件下长期运行的生物除磷系统中聚糖菌大量存在;而在中性(pH=7)和弱碱性(pH=8)条件下,聚磷菌在活性污泥中占有优势地位。静态实验结果表明,当pH在6⁸.5之间变化时,聚磷污泥的厌氧释磷能力随pH的升高而提高。pH在68.5之间变化时,聚磷污泥的厌氧释磷能力随pH的升高而提高。pH在6⁸之间变化时,乙酸吸收和PHB的合成能力随着pH升高而加强,当pH升高到8.5时,PHB合成能力下降,从而抑制了好氧段磷酸盐的吸收。pH为8时,生物除磷系统实现了充分的释磷和吸磷,并取得了最好的除磷效果。

Influence of pH on Microbial Community Structure and Metabolic Characteristics of PAOs in Biological Phosphorus Removal at Low Temperature

Impacts of pH on biological phosphorus removal(BPR) at low temperature were investigated in SBR reactors and batch experiments operated at 5 ℃.It was proved that pH affected not only the performance,but also the microbial community structure of BPR system.Acidic condition of pH 6 favored the accumulation of glycogen accumulating organisms(GAOs),while polyphosphate accumulating organisms(PAOs) take predominant roles at pH 7 and 8.Anaerobic acetate uptake and poly-β-hydroxybutyrate(PHB) formation capacity enhanced with pH increasing from 6 to 8.5.However as pH increased to 8.5,less PHB synthesized in anaerobic phase inhibited the uptake of orthophosphate in aerobic phase.Highest phosphorus removal efficiency was obtained in batch tests at pH 8 accompany with the maximum amount of phosphorus released and uptaken.