亚硝酸盐氮对生物除磷系统的影响

Nitrite effect on biological phosphorus removal process

摘要:

为全面评价亚硝酸盐氮对生物除磷系统的影响,采用两个SBR系统,模拟厌氧/好氧及厌氧/缺氧(以硝酸盐氮为电子受体)除磷系统,分别考察亚硝酸氮对二者的影响.结果显示:亚硝酸盐氮对好氧除磷系统的影响远大于缺氧除磷系统,亚硝酸盐氮对好氧和缺氧除磷在每克挥发性悬浮固体加入0.88和6.72 mgNO 2--N时会对生物活性产生抑制.同时发现在以硝酸盐氮为电子受体的反硝化除磷基础上采用逐渐增加亚硝酸氮质量浓度的方法驯化聚磷污泥,可以增加污泥对亚硝酸盐氮的适应性,并最终可以选择亚硝酸氮作为唯一电子受体吸磷,但其除磷效率低于以氧和硝酸盐氮为电子受体的除磷系统.

Abstract:

In this study,phosphorus accumulating organisms(PAOs) were cultivated in two SBR systems,one operated as anaerobic/aerobic mode,the other as anaerobic/anoxic mode.The effects of nitrite on the two modes of phosphorus removal system were investigated.The results showed that presence of nitrite inhibits both aerobic and anoxic phosphorus uptake,but aerobic phosphorus uptake was more affected than anoxic phosphorus uptake.In this research,0.88 mg/gVSS and 6.72 mg/gVSS were observed as threshold for aerobic and anoxic phosphate uptake,respectively.With the aid of a stepwise elevation of NO2——N added in influent,denitrifying phosphorus accumulating organisms were gradually accommodated to resist and utilize NO2——N as electron acceptor,but the phosphorus removal efficiency was lower than O2 and NO3——N as electron acceptors.