Wang Chenyu, Ji Bin, Li Anjie, Zhang Xiaoyuan, Liu Yu
Department of Water and Wastewater Engineering, School of Urban Construction, Wuhan University of Science and Technology, Wuhan 430065, China.
Key Laboratory of Water and Sediment Sciences of Ministry of Education, State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China.
Bioresour Technol. 2025 Nov;435:132944. doi: 10.1016/j.biortech.2025.132944. Epub 2025 Jul 7.
This study systematically investigates the impact of stirring speed on the performance of microalgal-bacterial granular sludge (MBGS) ranging from 0 to 250 rpm, revealing that an optimal speed of 210 rpm induces synergistic structural-metabolic adaptations in MBGS when treating simple organics. At this optimal stirring speed, improvements in granule morphology and homogeneity, indicated by a decreased non-uniformity coefficient, as well as enhanced roundness and an optimal microalgae-bacteria ratio were observed, which collectively contribute to structural integrity and stable granule size. Notably, at 210 rpm, a significant increase in the abundance of Pseudomonadota including key genera such as Aquimonas, Azonexus, and Dechloromonas was detected, which resulted in an up-regulation of the abundance of key functional genes involved in contaminant metabolism (e.g., DLD, SucD, glmS, and ppa). These findings highlight the importance of stirring shear force as a strategic approach for maintaining granule size and stability in MBGS technology for real-world applications.
本研究系统地研究了搅拌速度在0至250转/分钟范围内对微藻-细菌颗粒污泥（MBGS）性能的影响，结果表明，当处理简单有机物时，210转/分钟的最佳速度会在MBGS中引发协同的结构-代谢适应性变化。在这个最佳搅拌速度下，观察到颗粒形态和均匀性得到改善，表现为不均匀系数降低，以及圆度增加和微藻-细菌比例最佳，这些共同有助于结构完整性和稳定的颗粒大小。值得注意的是，在210转/分钟时，检测到包括关键属如水产单胞菌属、氮单胞菌属和脱氯单胞菌属在内的假单胞菌门丰度显著增加，这导致参与污染物代谢的关键功能基因（如双功能乳酸脱氢酶、琥珀酸脱氢酶亚基D、葡糖胺合成酶和磷酸烯醇式丙酮酸羧激酶）丰度上调。这些发现凸显了搅拌剪切力作为在实际应用的MBGS技术中维持颗粒大小和稳定性的一种策略性方法的重要性。
