Pincam Tararag, Liu Yong-Qiang, Booth Alexander, Wang Yi, Lan Guihong, Zeng Ping
Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, SO17 1BJ, UK.
Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, SO17 1BJ, UK.
Chemosphere. 2024 Aug;362:142644. doi: 10.1016/j.chemosphere.2024.142644. Epub 2024 Jun 18.
Understanding the microbial community structure of sludge is crucial for improving the design, operation and optimisation of full-scale wastewater treatment plants (WWTPs). This study aimed to have a comprehensive comparison of microbial communities between aerobic granular sludge and flocculent sludge from two full-scale sequential batch reactors-based WWTPs with nutrient removal for the first time. To better understand key functional bacteria such as polyphosphate accumulating bacteria (PAOs), competitive bacteria such as glycogen accumulating bacteria (GAOs) and nitrifying bacteria for both nitrogen and phosphorus removal, another two full-scale WWTPs with only carbon (C) removal and C and nitrogen (N) removal were compared too. It was found that the richness and diversity of the microbial population in sludge increased with pollutant removal from only C, C and N, to C,N, P removal. For C, N P removal, granule structure led to a more diverse and rich microbial community structure than flocculent structure. Although more abundant nitrifying bacteria were enriched in granular sludge than flocculent sludge, the abundance of total putative PAOs was equivalent. However, the most typical putative PAOs such as Tetrasphaera and Candidatus Accumulibacter seemed to be more correlated with biological phosphorus removal performance, which might be more proper to be used as an indication for P removal potential. The higher abundance of GAOs in flocculent sludge with better phosphorus removal performance might suggest that further investigation is needed to understand the functions of GAOs. In addition, the equivalent abundances of PAOs in the WWTPs with only C removal and with C, N, and P removal, respectively, indicate that many newly reported putative PAOs might not contribute to P removal. This study provides insight into the microbial communities and functional bacteria in aerobic granular sludge and flocculent sludge in full-scale SBRs, which can provide microbes-informed optimisation of reactor operation for better nutrient removal.
了解污泥的微生物群落结构对于改进全尺寸污水处理厂（WWTPs）的设计、运行和优化至关重要。本研究旨在首次全面比较两座基于序批式反应器的全尺寸具有脱氮除磷功能的污水处理厂中好氧颗粒污泥和絮状污泥的微生物群落。为了更好地了解诸如聚磷菌（PAOs）等关键功能菌、诸如糖原积累菌（GAOs）等竞争菌以及用于氮磷去除的硝化细菌，还比较了另外两座分别仅去除碳（C）以及去除碳和氮（N）的全尺寸污水处理厂。研究发现，随着污染物去除从仅去除C、C和N到去除C、N、P，污泥中微生物种群的丰富度和多样性增加。对于C、N、P去除，颗粒结构导致的微生物群落结构比絮状结构更加多样和丰富。尽管颗粒污泥中富集的硝化细菌比絮状污泥中更丰富，但假定的总PAOs丰度相当。然而，最典型的假定PAOs如Tetrasphaera和“Candidatus Accumulibacter”似乎与生物除磷性能更相关，可能更适合用作除磷潜力的指标。在具有更好除磷性能的絮状污泥中GAOs丰度较高，这可能表明需要进一步研究以了解GAOs的功能。此外，分别仅去除C以及去除C、N和P的污水处理厂中PAOs丰度相当，这表明许多新报道的假定PAOs可能对除磷没有贡献。本研究深入了解了全尺寸序批式反应器中好氧颗粒污泥和絮状污泥中的微生物群落和功能菌，可为基于微生物信息的反应器运行优化提供参考，以实现更好的养分去除。
