Due to the characteristics of kitchen waste such as high moisture content, high organic matter content, and easily for decomposition, inappropriate management of kitchen waste can cause a waste of resources and pollution to the environment. More and more attention has been paid to the reduction, harmlessness and recycling treatment of kitchen waste in recent years. In order to reduce the kitchen waste as well as produce clean energy such as hydrogen gas, the effect of pH on hydrogen production during anaerobic fermentation of steamed kitchen waste was investigated in a sequencing batch anaerobic fermentation reactor inoculated with residual sludge from wastewater treatment plant, with a substrate/inoculum ratio of 4/1 and an inoculation temperature of 37 ℃. Butyric acid and acetic acid were the most important components in the substrate, which accounted for more than 80% of the total volatile acid, and there was only a small amount of propionic acid. This suggested that it was a typical type of butyric acid fermentation process. The results showed that the optimized initial pH was 9.0, which lead to the maximum cumulative gas production rate of 748 mL and the maximum hydrogen production quantity of 371 mL. In the whole process of anaerobic fermentation, the highest hydrogen volume fraction was up to 80.5%, and the average hydrogen production rate and unit capacity of hydrogen (VS) was 10.31 mL·h-1and 72.9 mL·g-1, respectively. The removal rate of VS and TS was up to 26.6% and 34.4%, respectively. The activity of dehydrogenase increased during 0~16 h and then decreased gradually over time, which was positively related to the hydrogen production when the initial pH was 9.0. The highest activity of dehydrogenase was detected at 16 h, when the maximum hydrogen production rate was achieved as 19.2 mL·h-1. Therefore, the efficiency of hydrogen production from anaerobic fermentation of kitchen waste can be improved by adjusting the initial pH, which can provide useful information for the application of clean energy production during reduction of the kitchen waste.%餐厨垃圾具有含水率高、有机物含量高、易腐败等特点,若处理不当,必然造成资源浪费和环境污染.餐厨垃圾减量化、无害化、资源化处理是环境科学领域近年来关注的热点与难点.为解决餐厨垃圾的减量化问题,同时产生清洁能源——氢气,利用自制小型序批式厌氧发酵产氢反应装置,以蒸煮餐厨垃圾为发酵底物,接种污水处理厂剩余污泥进行厌氧发酵产氢,在底物与接种物质量比为4:1,温度为37℃的条件下,研究pH对蒸煮餐厨垃圾厌氧发酵产氢的影响.结果表明,厌氧发酵底物中乙酸和丁酸是挥发性酸(VFA)中主要的组成部分,占总挥发性酸的80%以上,同时含有少量的丙酸,属于典型的丁酸型发酵.初始pH为9.0时,厌氧发酵效果最佳,累积产气量和产氢量最大,分别为748 mL和371 mL;在整个厌氧发酵过程中氢气的体积分数最高可达80.5%,平均产氢速率为10.31 mL·h-1,单位产氢量(以VS计)为72.9 mL·g-1,总固体(TS)和挥发性固体(VS)的去除率分别高达26.6%和34.4%;脱氢酶的活性呈现出先增强后减弱的趋势,产氢速率与脱氢酶的活性呈正相关;发酵反应进行到16 h时,脱氢酶的活性最好,此时产氢速率最大,为19.2 mL·h-1.因此,调节初始pH为9.0,可以提高餐厨垃圾产氢效率,实现餐厨垃圾减量化和产生清洁能源的双重目标.
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