The effects of adsorption, sulfamethoxazole (SMX) content, chemical oxygen demand (COD), and dissolved oxygen (DO) are recognized to be crucial for SMX removal in the aerobic granular sludge (AGS) system. Therefore, we investigated the impact of adsorption and these three different environmental factors on the SMX removal loading rate and removal efficiency of an AGS system, and determined the differences in microbial community composition under different environmental conditions. Adsorption was not the main SMX removal mechanism, as it only accounted for 5% of the total removal. The optimal SMX removal conditions were obtained for AGS when the COD, DO, and SMX concentrations were 600 mg/L, 8 mg/L, and 2,000 µg/L, respectively. The highest SMX removal efficiency was 93.53%. Variations in the three environmental factors promoted the diversity and changes of microbial communities in the AGS system. Flavobacterium, Thauera, and norank_f_Microscillaceae are key microorganisms in the AGS system. Thauera, and norank_f_Microscillaceae were sensitive to increases in SMX concentrations and beneficial for degrading high SMX concentrations. In particular, Flavobacterium abundances gradually decreased with increasing SMX concentrations.

吸附、磺胺甲恶唑 (SMX) 含量、化学需氧量 (COD) 和溶解氧 (DO) 的影响被认为是好氧颗粒污泥 (AGS) 系统中 SMX 去除的关键。因此，我们研究了吸附和这三种不同环境因素对 AGS 系统的 SMX 去除负载率和去除效率的影响，并确定了不同环境条件下微生物群落组成的差异。吸附不是主要的 SMX 去除机制，因为它仅占总去除量的 5%。当 COD、DO 和 SMX 浓度分别为 600 mg/L、8 mg/L 和 2,000 µg/L 时，AGS 获得了最佳 SMX 去除条件。最高的 SMX 去除效率为 93.53%。Flavobacterium、Thauera和norank_f_Microscillaceae是 AGS 系统中的关键微生物。Thauera和norank_f_Microscillaceae对 SMX 浓度的增加敏感，有利于降解高 SMX 浓度。特别是，随着 SMX 浓度的增加，黄杆菌丰度逐渐下降。