pH值对SBR单级好氧生物除磷的影响

在2个序批式反应器(R1、R2)中,以合成废水为对象,研究了不同pH值(R1:pH8±0.2;R2:pH7±0.2)对单级好氧生物除磷的影响;并通过比较周期中主要储能物质的变化,探讨了产生不同除磷效果的原因.结果表明,R1与R2均具有较高除磷性能,R1与R2中的平均去除率分别为94.9%,83.5%,pH值对SBR单级好氧生物除磷有一定的影响.导致R1具有较高除磷性能的原因是其对聚磷的依赖程度更大.好氧段R1糖原积累量低于R2(R1为1.42mmol/g,R2为1.55mmol/g),但降解量却高于R2(分别为1.41,1.19mmol/g);静置期,R1中糖原无明显变化,R2中则观察到明显的糖原降解.R1与R2均有明显的释磷现象,R1释磷量高于R2(释磷量分别为9.65,7.33mg/L).整个周期中,R1中PHA无明显变化,而R2中则在好氧段有少量减少,静置期有少量上升.

Effect of pH on phosphorus removal in sequencing batch reactor with single-stage oxic process

To investigate the effect of pH on biological phosphorus removal in single-stage oxic process,two lab-scale sequencing batch reactors (SBRs) were operated (R1:pH 8±0.2;R2:pH 7±0.2) using synthetic wastewater,and variations of the main intracellular polymer during a cycle were also compared to discuss the probable reasons for different performances of phosphorus removal.Both R1 and R2 performed well in phosphorus removal,94.9% and 83.5% of the average efficiencies of phosphorus removal in R1 and R2 were respectively obtained,suggesting that the effect of pH on phosphorus removal was slight in such a single-stage oxic process.The reason for the higher performance of phosphorus removal in RI was its stronger dependence on polypbosphate.During the aerobic period,the accumulation of glycogen by bacteria in R1 was lower than that in R2 (R1:1.42mmol/g,R2:1.55mmol/g),but the degradation of glycogen in R1 was higher than that in R2 (R1:1.41 mmol/g,R2:1.19mmol/g);in the idle phase,glycogen in R2 degraded obviously while that in R1 seldom degraded.Besides,though obvious phosphorus release was observed in both R1 and R2,the content of phosphorus released in R1 was higher than that in R2 (R1:9.65mg/L,R2:7.33mg/L).A slight decrease and increase of PHA were respectively observed during the aerobic and the idle periods in R2 while no obvious change of PHA was found in R1 during the whole period.