醋酸预处理对牛粪与水稻秸秆混合厌氧发酵特性的影响

为了探究醋酸预处理提高厌氧发酵产气量的原因，研究用醋酸预处理水稻秸秆，之后将预处理后的水稻与牛粪混合进行厌氧发酵，测定发酵初始环境和发酵过程中纤维素酶活力、还原性糖含量、VFA 含量、pH 及日产气量，并且对其发酵过程中的稳定性系数进行分析。结果表明，水稻秸秆在 4%的醋酸浓度下预处理 4 d 处理组的总沼气产量最高为 11 605 mL，且显著高于未经预处理总沼气量 6 450 mL（P<0.01），且该处理的日产气量的峰值提高和出现的时间提前；厌氧发酵的初始环境、过程环境、环境稳定性以及他们之间的相互作用关系受醋酸预处理影响；醋酸预处理提高总沼气产量的主要原因是，醋酸预处理使厌氧发酵初始环境和过程环境更加协调，使发酵系统更加稳定。研究表明，醋酸预处理能够显著提高沼气产量，为醋酸预处理技术提供一定的参考。

Effect of acetic acid pretreatment on anaerobic fermentation characteristics of mixed cow dung and rice straw

In order to explore the reasons for the pretreatment of acetic acid to increase the gas production of anaerobic fermentation, the study of pretreatment of rice straw with acetic acid and then mixed with cow dung for anaerobic fermentation. Besides, the mixtures were used to determine the influence factors of the initial fermenta- tion environment and fermentation process by anaerobic fermentation. The enzyme activity, reducing sugar con- tent, VFA content, pH and daily gas production, and the stability coefficient during the fermentation process were analyzed. The results showed that the total biogas production of rice straw treated at 4% acetic acid concentration for 4 days was 11 605 mL, which was significantly higher than the total pre-treated total biogas volume of 6450mL (P<0.01), and the peak of the daily gas production of the treatment increased and time was advanced. The initial environment, process environment, environmental stability and interaction between anaerobic fermentation are affected by acetic acid pretreatment. The main reason for the increase of total biogas production by acetic acid pretreatment is that the pretreatment of acetic acid makes the initial environment and process environment of an- aerobic fermentation more coordinated and promotes the stability of the fermentation system. Studies have shown that acetic acid pretreatment can significantly increase biogas production and provide a reference for acetic acid pretreatment technology.