Rice straw is an abundant lignocellulosic biomass used to produce biogas. However, its resistant structure hinders biogas production. In this study, three pretreatments, microwave, ammoniation, and microwave-assisted ammoniation (MAA), were evaluated for their use in improving biogas production from rice straw. After an 18-day digestion, methane production by rice straw pretreated with MAA was 281.56 mL/g (volatile solids of substrate), which was 25.43%, 7.96%, and 18.18% more than that produced following the control, microwave, and ammoniation pretreatments, respectively. These increases were mainly attributed to the change in the resistant structure of rice straw following the MAA pretreatment and a more stable anaerobic digestion system. The degradation rate for the volatile solids of the rice straw pretreated with MAA during anaerobic digestion was 71.20%, which was 4.71%, and 4.86% higher than the rates observed using microwave and ammoniation pretreatments, respectively. In addition, the MAA method had a T₉₀ fermentation cycle of 6 days, which was 33.3%, 25.0%, and 33.3% shorter than those for the control, microwave, and ammoniation methods, respectively. This technology shows the potential to enhance biogas production from the anaerobic digestion of rice straw.

稻草是一种丰富的木质纤维素生物质，用于生产沼气。然而，其抗性结构阻碍了沼气生产。在本研究中，对微波、氨化和微波辅助氨化 (MAA) 这三种预处理方法在提高稻草沼气生产中的应用进行了评估。经过18天的消化，MAA预处理的稻草甲烷产量为281.56 mL/g（底物挥发性固体），分别比对照、微波和氨化后的甲烷产量分别增加25.43%、7.96%和18.18%分别进行预处理。这些增加主要归因于 MAA 预处理后稻草抗性结构的变化和更稳定的厌氧消化系统。厌氧消化过程中用 MAA 预处理的稻草挥发性固体的降解率为 71.20%，分别比使用微波和氨化预处理观察到的降解率高 4.71% 和 4.86%。此外，MAA 方法有一个 T₉₀发酵周期 6 天，分别比对照、微波和氨化方法缩短 33.3%、25.0% 和 33.3%。该技术显示了通过稻草厌氧消化提高沼气产量的潜力。