The autotrophic process for nitrogen removal has attracted worldwide attention in the field of wastewater treatment, and the performance of this process is greatly influenced by the size of granular sludge particles present in the system. In this work, the granular sludge was divided into three groups, i.e. large size (> 1.2 mm), medium size (0.6–1.2 mm) and small size (< 0.6 mm). The medium granular sludge was observed to dominate at high volumetric nitrogen loading rates, while offering strong support for good performance. Its indispensable contribution was found to originate from improved settling velocity (0.84 ± 0.10 cm/s), high SOUR-A (specific oxygen uptake rate for ammonia oxidizing bacteria, 25.93 mg O₂/g MLVSS/h), low SOUR-N (specific oxygen uptake rate for nitrite oxidizing bacteria, 3.39 mg O₂/g MLVSS/h), and a reasonable microbial spatial distribution.

中文翻译：

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颗粒污泥粒径对自养脱氮系统性能的影响及其生物学机制。

自养脱氮工艺在废水处理领域引起了全世界的关注，并且该工艺的性能在很大程度上受到系统中存在的颗粒污泥颗粒尺寸的影响。在这项工作中，颗粒污泥分为三类，即大尺寸（> 1.2 mm），中尺寸（0.6-1.2 mm）和小尺寸（<0.6 mm）。观察到中等粒状污泥在高体积氮负载率下占主导地位，同时为良好性能提供了有力支持。发现其不可或缺的贡献来自提高的沉降速度（0.84±0.10 cm / s），高的SOUR-A（氨氧化细菌的特定吸氧率，25.93 mg O ₂ / g MLVSS / h），低的SOUR-N（亚硝酸盐氧化细菌的特定氧气吸收率，3.39 mg O₂ / g MLVSS / h），以及合理的微生物空间分布。