短程硝化厌氧氨氧化耦合MBR工艺膜污染特性分析
- The study of fouling behavior in the partial nitrification anammox coupled with MBR
- 基金项目：国家自然科学基金(No. 51778014)
- 摘要：短程硝化厌氧氨氧化（partial nitrification anammox，PNA）耦合膜生物反应器（membrane bioreactor，MBR）的相关研究十分有限，尤其缺乏对该耦合系统的膜污染特性研究.本研究采用连续流反应器PNA-MBR，对该反应器内活性污泥和膜表面饼层污泥特性进行了较为系统的分析和比较.结果表明，膜表面饼层污泥的平均粒径更大，饼层污泥中提取的EPS具有更高浓度的蛋白质、多糖及腐殖质类物质，蛋白质二级结构更疏松、暴露的疏水性官能团更多.死端膜滤实验表明，与活性污泥EPS相比，膜表面饼层污泥EPS造成的膜污染更严重.相关性分析表明，腐殖质类物质是造成活性污泥EPS和饼层污泥EPS比通量下降的主要原因.微生物群落分析表明，与活性污泥相比，饼层污泥的微生物群落多样性更高，Patescibacteria和norank_f__norank_o__norank_c__SJA-28的相对丰度高于活性污泥，是造成膜污染的主要微生物.
- Abstract：There is limited research on partial nitrification anammox (PNA) coupled with membrane bioreactor (MBR), especially the lack of membrane fouling behavior of this coupled system. In this study, the cake and bulk sludge from a continuous flow PNA-MBR were analyzed and compared. The results showed that the average particle size of the cake sludge was larger than that of the suspended sludge, and the EPS extracted from cake sludge had higher concentration of protein, polysaccharide, and humic substances. Moreover, The EPS extracted from cake sludge had looser protein secondary structure and stronger surface hydrophobicity. Dead-end membrane filtration experiments showed that membrane fouling caused by the EPS extracted from cake sludge was more serious than that of suspended sludge. The effect of humic substances on normalized flux was significant. Microbial community analyses showed that the microbial community exhibited higher diversity in cake sludge. Additionally, the relative abundance of Patescibacteria and norank_f__norank_o__norank_c__SJA-28 was higher in cake sludge than that in suspended sludge, implying a higher membrane fouling potential.
