Polyacrylamide (PAM) is generally employed in wastewater treatment processes such as sludge dewatering and therefore exists in the sludge. Furthermore, it degrades slowly and can deteriorate methane yield during anaerobic digestion (AD). The impact or fate of PAM in AD under thermophilic conditions is still unclear. This study mainly focuses on PAM degradation and enhanced methane production from PAM-added sludge during 15 days of thermophilic (55°C) AD compared to mesophilic (35°C) AD. Sludge and PAM dose from 10 to 50 g/kg TSS were used. The results showed that PAM degraded by 76% to 78% with acrylamide (AM) content of 0.2 to 3.3 mg/L in thermophilic AD. However, it degraded only 27% to 30% with AM content of 0.5 to 7.2 mg/L in mesophilic AD. The methane yield was almost 230 to 238.4 mL g VSS on the 8th day in thermophilic AD but was 115.2 to 128.6 mL/g VSS in mesophilic AD. Mechanism investigation revealed that thermophilic AD with continuous stirring not only enhanced PAM degradation but also boosted the organics release from the sludge with added PAM and gave higher methane yield than mesophilic AD.

聚丙烯酰胺（PAM）通常用于废水处理过程（如污泥脱水）中，因此存在于污泥中。此外，它在厌氧消化（AD）期间会缓慢降解并可能降低甲烷产量。尚不清楚PAM在嗜热条件下在AD中的影响或命运。这项研究主要关注与嗜温（35°C）AD相比，嗜热（55°C）AD 15天期间PAM降解和添加PAM的污泥产生甲烷的增加。使用10至50 g / kg TSS的污泥和PAM剂量。结果表明，在嗜热性AD中，PAM降解率为76％至78％，丙烯酰胺（AM）含量为0.2至3.3 mg / L。然而，在嗜温性AD中，其降解仅为27％至30％，AM含量为0.5至7.2 mg / L。在嗜热性AD中，第8天的甲烷产量几乎为230至238.4 mL g VSS，但为115。在嗜温性AD中为2至128.6 mL / g VSS。机理研究表明，连续搅拌的嗜热性AD不仅增强了PAM的降解，而且还增加了PAM的添加，从而增加了污泥中有机物的释放，甲烷的收率高于中温性AD。