亚硝酸盐对聚磷菌厌氧代谢的影响

Effect of Nitrite on Anaerobic Metabolism of Candidatus Accumulibacter Phosphates

为进一步认识聚磷菌(phosphate accumulating organism,PAOs)的代谢机制以及影响因素,在厌氧-好氧交替运行的SBR反应器中,采用人工配水,富集了含量高达80%以上的聚磷菌Candidatus Accumulibacter Phos-phates,在此基础上,用静态试验的方法研究了突然投加不同质量浓度的亚硝酸盐(ρ(NO 2--N)=0、5、10、20、40mg/L)对聚磷菌厌氧放磷的影响.结果表明,前60 min,随着起始ρ(NO 2--N)从0 mg/L提高到40 mg/L,释磷量不断增加,起始ρ(NO2--N)为40 mg/L的反应器比起始ρ(NO2--N)为0 mg/L的反应器释磷量增加了近60%,而乙酸吸收速率和PHA合成量却几乎下降了20%.60 min后,ρ(PO34--P),ρ(NO2--N)以及ρPHA都出现下降趋势,系统发生了反硝化吸磷.结果表明,此系统富集的PAOs中,一部分具有反硝化除磷的功能,还有一部分会因为亚硝酸盐的进入对其发生毒害而自溶.

In order to investigate the metabolism of Candidatus Accumulibacter Phosphates （a well-known phosphate accumulating organism） and its affecting factors, anaerobic-aerobic SBR reactor was performed to incubate polyphosphate accumulating organism （PAO） using synthetical sewage, and the content of PAOs reached more than 80%. Based on the enriched culture, several batch experiments were taken. The results indicated that when acetate and nitrite were both in the reactor （in 60min）, with the increasing of the initial nitrite, Accumulibacter released much more PO4^3- -P, whereas the acetate uptake rate and the amount of accumulated PHA decreased. After 60min,the concentration of phosphate,nitrate and PHA were all degressive, suggesting that denitrifying phosphorus removal were occurred. The results suggested that there were denitrifying phosphorus organisms. Besides,there were a part of PAOs which could be poisoned by nitrite in this system.