Autothermal thermophilic aerobic digestion (ATAD) is used to treat human excreta hygienically. We previously reported a unique full-scale ATAD, showing distinctive bacterial community transitions and producing high-nitrogen-content liquid fertilizer; nevertheless, the mechanism remains unclear. One hypothesis involves using a gas-inducing (GI) agitator. We designed a lab-scale GI system and compared it with a disk-turbine (DT) agitator system by mimicking the temperature shift of full-scale ATAD. The agitation system and its agitation speed greatly affected physicochemical properties and bacterial community structure. GI system at 1000 rpm (GI1000; high total carbon removal efficiency, 88.3%), with few nitrifying and denitrifying bacteria, maintained a high ammoniacal nitrogen concentration and had more shared operational taxonomic units related to Acinetobacter sp., Arcobacter sp., and Longimicrobium sp. with the full-scale ATAD compared with the GI system at 490 rpm and DT system at 1000 rpm (DT1000). Furthermore, DT1000, with a high abundance of nitrifying and denitrifying bacteria such as Alcaligenes aquatilis and Pseudomonas caeni, removed 94.7% total nitrogen with 71.9% total carbon removal efficiency. These results suggested that shear stress and oxygen supply system would change the bacterial community structure, thus affected ATAD performances. Consequently, it is possible that ATAD can be applied for not only production of highly nitrogen-containing liquid fertilizer but also extremely nitrogen removal of wastewater.

自热嗜热好氧消化 (ATAD) 用于卫生地处理人类排泄物。我们之前报道了一种独特的全尺寸 ATAD，显示出独特的细菌群落转变并生产高氮含量的液体肥料；尽管如此，该机制仍不清楚。一种假设涉及使用气体诱导 (GI) 搅拌器。我们设计了一个实验室规模的 GI 系统，并通过模拟全尺寸 ATAD 的温度变化将其与盘式涡轮 (DT) 搅拌器系统进行比较。搅拌系统及其搅拌速度极大地影响了理化性质和细菌群落结构。GI系统在1000转（GI1000；高总碳去除效率，88.3%），硝化和反硝化细菌很少，不动杆菌属、弧杆菌属和长微菌属。与 490 rpm 的 GI 系统和 1000 rpm (DT1000) 的 DT 系统相比，全尺寸 ATAD。此外，DT1000 具有高丰度的硝化和反硝化细菌，如Alcaligenes aquatilis和Pseudomonas caeni，去除了 94.7% 的总氮，总碳去除效率为 71.9%。这些结果表明剪切应力和供氧系统会改变细菌群落结构，从而影响 ATAD 性能。因此，ATAD 不仅可以用于生产高含氮液体肥料，还可以用于废水的极脱氮。