The influences of flow patterns (mixed-flow and plug-flow) and fermentation pretreatment on aerobic granular sludge (AGS) formation with various substrate availability levels were investigated by running four identical laboratory-scale sequencing batch reactors (R1-R4), comparing two anaerobic feeding strategies and three kinds of substrates. R1 achieved faster granulation with a fast influent fill step followed by a modified anaerobic mixed-flow phase, but the AGS showed poorer stability with a cracked structure and a high suspended solids concentration in the effluent. The anaerobic plug-flow feeding mode (with influent fed slowly from the bottom) in R2 provided deeper penetration depth for the substance to reach the core of AGS and accordingly strengthen AGS stability. An acidogenic up-flow sludge bed reactor was introduced as a pretreatment to improve the AGS performance by enhancing glucose pre-fermentation (R4). AGS fed with mixed volatile fatty acids (VFA) after glucose fermentation showed similar performance compared with the reactor fed with acetate in the aspects of stability, structure, size distribution and nitrogen removal efficiency, and 74% similarity in the microbial community. For actual wastewater with low VFA concentrations, fermentation treatment was suggested as a promising pretreatment for stable AGS granulation and operation.

通过运行四个相同的实验室规模的测序批量反应器（R1-R4），比较了两个不同的底物利用率水平，研究了流动方式（混合流和活塞流）和发酵预处理对好氧颗粒污泥（AGS）形成的影响。厌氧饲养策略和三种基质。R1通过快速的进水填充步骤以及随后的改进的厌氧混合流相实现了更快的制粒，但是AGS显示出较差的稳定性，带有裂化结构和废水中的高悬浮固体浓度。R2中的厌氧塞流进料方式（从底部缓慢进水）为物质到达AGS的核心提供了更深的渗透深度，从而增强了AGS的稳定性。引入产酸上流污泥床反应器作为预处理，以通过增强葡萄糖预发酵（R4）来提高AGS性能。葡萄糖发酵后添加混合挥发性脂肪酸（VFA）的AGS在稳定性，结构，尺寸分布和脱氮效率方面以及在微生物群落中74％的相似性方面，与添加乙酸盐的反应器相比具有相似的性能。对于VFA浓度低的实际废水，建议将发酵处理作为稳定AGS制粒和运行的有前途的预处理方法。微生物的大小分布和脱氮效率，以及74％的相似性。对于VFA浓度低的实际废水，建议将发酵处理作为稳定AGS制粒和运行的有前途的预处理方法。微生物的大小分布和脱氮效率，以及74％的相似性。对于低VFA浓度的实际废水，建议将发酵处理作为稳定AGS制粒和运行的有前途的预处理方法。