除磷颗粒诱导的同步短程硝化反硝化除磷颗粒污泥工艺

以低C/N比生活污水为研究对象,接种成熟除磷颗粒污泥,通过联合调控好氧时间及曝气强度成功将其诱导成具有同步短程硝化反硝化除磷功能的颗粒污泥,并分析了此过程中系统脱氮除磷特性变化.结果表明,好氧段曝气强度为5L·(h·L)~(-1),在较短曝气时间下(140 min)可实现AOB的富集,但同步硝化反硝化能力难以提高;降低曝气强度为3. 5L·(h·L)~(-1),延长曝气时间(200 min),好氧段氮损增加.根据pH及DO曲线进一步优化曝气时长抑制NO_2~-向NO_3~-转化,优化后系统出水TP 0. 5 mg·L~(-1)和TN 15 mg·L~(-1),可实现氮磷的同步去除.在系统功能由单纯的除磷向同步脱氮除磷转化的过程中,释磷量下降,PAOs在内碳源储存过程中的贡献比例有所下降,但仍占主体地位(60%).批次实验表明,颗粒中可利用NO_2~-为电子受体的DPAOs占绝大部分达52. 43%,其富集减轻了系统的碳源压力,从而改善脱氮除磷效果.

Simultaneous Short-Cut Nitrification-Denitrification Phosphorus Removal Granules Induced by Phosphorus Removal Granules

This paper investigated domestic sewage with a low C/N ratio. Mature phosphorus removal granules were inoculated to cultivate granules with a simultaneous short-cut nitrification and denitrification function. The characteristics of nitrogen and phosphorus removal of this process were analyzed. Results show that AOB can be enriched by prolonging the sludge age for 30 days with an aeration intensity of 5 L·(h·L)^-1 and shorter aeration time (140 min), whereas the simultaneous nitrification and denitrification ability could not be improved. The nitrogen loss increased at the aerobic time when aeration intensity was reduced by 3.5 L·(h·L)^-1 and aeration time was prolonged by 200 min. The aeration time was further optimized to restrain the transformation of NO₂^- to NO₃^-, and finally the effluent of TP < 0.5 mg·L^-1 and TN < 15 mg·L^-1. During the process of the system function transformation from phosphorus removal to nitrogen and phosphorus removal, the phosphorus release decreased, however PAOs still played a dominant role (60%) in the process of internal carbon storage. Batch experiments showed that DPAOs that can utilize nitrite as an electron acceptor accounts for 52.43% in the total PAO_S, which alleviated the pressure of the carbon source and improved the simultaneous nitrogen and phosphorus removal.