蔬菜与餐厨垃圾厌氧发酵启动阶段微生物分析

为了研究厌氧发酵启动阶段微生物菌群结构、数量变化情况与沼气产量的关系，分别对蔬菜废弃物和餐厨垃圾单一物料发酵进行分析，并测定pH值、挥发性脂肪酸（VFA）、氧化还原电位。结果表明，餐厨垃圾比蔬菜废弃物的启动时间长，但产气持久。蔬菜废弃物中细菌达峰值的时间早于餐厨垃圾，说明蔬菜废弃物中的有机质更利于微生物降解利用。两种原料中的微生物群落结构变化一致，启动阶段初期好氧和兼性厌氧细菌属优势菌，其中产酸菌增殖速率高于氨化细菌，是启动阶段降解有机质的主要菌群。随后厌氧细菌快速增殖，13增殖速率由不足20％增长到近100％并保持稳定。厌氧纤维素降解菌在启动阶段增殖较慢，原料中纤维素降解在厌氧发酵后期。原料液VFA中丁酸含量最多，最高浓度4．7mg／mL以上，占有机酸总量总量的46％以上，厌氧发酵类型为丁酸发酵型。

Analysis of microorganism at starting stage of anaerobic fermentation of vegetable waste and restaurant garbage

In order to study effects of alternative evolution in microorganism on gas production at starting stage of anaerobic fermentation, vegetable waste and restaurant garbage as raw materials respectively were ana- lyzed. Trends of pH value, volatile fatty acid （VFA） and oxidation-reduction potential were also determitled. The results show that the starting and gas production stage of restaurant garbage are longer than that of vegetable waste. The period of peak value of microorganism in vegetable waste is earlier than that of restaurant garbage. Organic in vegetable waste is more beneficial to degradation microorganism. The changes of microorganism com- munity structure in two raw materials are uniform. Aerobic and facultative anaerobes are the dominant at early starting stage, the peak value of acidogenic bacteria is precede to the ammonification bacteria. Then the prolifer- ation rate of anaerobic bacteria increases from less than 20% to almost 100% at the late starting stage. The anae- robic cellulose-decomposing bacteria grow slowly at starting mL, account for over 46% of total VFA. stage. The content of n-butyric acid is over 4.7 mg/