Anaerobic digestion (AD) of animal manure converts only half of the organic material into biogas due to the presence of a significant amount of lignocellulosic materials in manure. In this study, alkaline thermal pretreatment was used for improving anaerobic digestion of residual manure fibers after AD. Anaerobic digestion of pretreated manure fibers was done in batch culture under mesophilic and thermophilic conditions. The results of the study showed that degradation of manure fibers was improved ca. 43.6% as a result of alkaline thermal pretreatment with 3% w/w NaOH added. Methane yield improved by 143.5 and 180.2% under mesophilic and thermophilic conditions, respectively. Compositional analysis of the effluent after AD showed the percentile conversion of 50.8% of cellulose, 59.5% of hemicellulose, 39.9% of acid-soluble and 21.7% of acid-insoluble lignin to methane under mesophilic conditions. Under thermophilic conditions, 57.3% of cellulose, 70.1% of hemicellulose, 39.4% of acid-soluble and 19.4% of acid-insoluble lignin were converted to methane. The result showed that alkaline thermal pretreatment of manure fibers can enhance the performance of AD while shortening the time needed to recover the maximum amount of biogas from AD.

动物粪便的厌氧消化（AD）仅将一半有机物转化为沼气，这是因为粪便中存在大量的木质纤维素物质。在这项研究中，碱性热预处理用于改善AD后残留肥料纤维的厌氧消化。在中温和嗜热条件下，分批培养进行预处理的粪肥纤维的厌氧消化。研究结果表明，粪肥纤维的降解得到了改善。碱热预处理（添加3％w / w NaOH）的结果为43.6％。在中温和高温条件下，甲烷收率分别提高了143.5％和180.2％。AD后废水的成分分析表明，百分转化率为50.8％的纤维素，59.5％的半纤维素，39.9％的酸溶性和21。在嗜温条件下，有7％的酸不溶性木质素转化为甲烷。在嗜热条件下，将57.3％的纤维素，70.1％的半纤维素，39.4％的酸溶性木质素和19.4％的酸不溶性木质素转化为甲烷。结果表明，粪肥纤维的碱热预处理可以提高AD的性能，同时缩短从AD中回收最大沼气所需的时间。