磷酸盐对厌氧氨氧化活性污泥脱氮效能的影响

通过接种厌氧氨氧化污泥,研究了磷酸盐浓度变化对厌氧氨氧化活性污泥脱氮效能长短期的影响,对其抑制动力学参数进行拟合,并基于荧光定量PCR的测定,分析了受磷酸盐抑制前后反应器中厌氧氨氧化细菌丰度的变化.短期研究结果表明,磷酸盐浓度小于30 mg·L~(-1)对厌氧氨氧化污泥的脱氮效能没有明显的影响;随着进水磷酸盐浓度的升高,氮去除速率呈加速下降趋势;磷酸盐浓度大于200 mg·L~(-1)时,厌氧氨氧化污泥活性达到完全的抑制状态;采用Haldane抑制模型拟合磷酸盐抑制的动力学参数,所得半抑制常数为70.1 mg·L~(-1).长期研究结果表明,磷酸盐浓度小于50 mg·L~(-1)时,对厌氧氨氧化污泥脱氮效能的影响不大;磷酸盐浓度在70~90 mg·L~(-1)时,厌氧氨氧化污泥活性开始受到明显影响,经过一段时间可以有所恢复,但磷酸盐浓度越高,恢复所需时间越长;当磷酸盐浓度达到100 mg·L~(-1)时厌氧氨氧化污泥的脱氮效能受到严重抑制,氮去除速率由158.33 g·(m~3·d)~(-1)下降至60.17 g·(m~3·d)~(-1)左右,抑制约62%.荧光定量PCR结果表明,抑制后的污泥体系中ANAMMOX菌细胞浓度由(9.97±0.86)×107cells·m L~(-1)下降至(8.26±0.54)×107cells·m L~(-1),有相对减少的趋势.

Influence of Phosphate on Nitrogen Removal Efficiency of ANAMMOX Sludge

In this study, the effect of phosphate concentration on the nitrogen removal efficiency of ANAMMOX sludge was researched. The inhibition kinetic parameters were fitted and the abundance of ANAMMOX bacteria in the reactor before and after phosphate inhibition was analyzed by Real-time PCR. The short-term experiments showed that there was no significant effect on the nitrogen removal efficiency of ANAMMOX sludge when phosphate concentration was less than 30mg·L^-1. With the increase of influent phosphate concentration, the removal rate of nitrogen decreased rapidly. When the phosphate concentration was raised to 200mg·L^-1, the activity of ANAMMOX sludge reached a complete inhibition state. The parameters of phosphate inhibition were fitted by Haldane inhibition model. The half-inhibition constant was 70.1 mg·L^-1. The long-term results showed that when the phosphate concentration was less than 50 mg·L^-1, the effect on the nitrogen removal efficiency of ANAMMOX sludge was not significant. When the phosphate concentration reached 70-90 mg·L^-1, The activity of ANAMMOX sludge was obviously affected, and the stability could be restored after a certain period. Increasing the phosphate concentration had a more significant effect and resulted in a longer recovery time. Finally, when the concentration of phosphate reached 100 mg·L^-1, the nitrogen removal efficiency of ANAMMOX was seriously inhibited. The rate of nitrogen removal decreased from 158.33 g·(m³·d)^-1 to 60.17 g·(m³·d)^-1, resulting in 62% inhibition. The results of real-time PCR showed that the concentration of ANAMMOX was decreased from (9.97±0.86)×10⁷ cells·mL^-1 to (8.26±0.54)×10⁷ cells·mL^-1 in the restraining sludge system, and there was a relatively reduced trend.