固定化酶酸化/UASB两相厌氧有机酸代谢特征

以固定化酶酸化相和UASB产甲烷相为两相厌氧系统进行连续流实验,研究了酸化相和产甲烷相中的有机酸和乙醇的变化特征、变化速率,挥发性有机酸组成,发酵类型以及对COD去除率的影响.结果表明:酸化相的酸化率为28.2%,水解产物组成中乙醇>乙酸>丁酸>丙酸,其中乙醇占44.8%,乙酸占38.4%,丙酸为6.9%,丁酸为9.8%,为乙醇型发酵类型.在产甲烷相中乙醇被去除99.8%,乙酸为92.0%,丙酸为59.1%,丁酸为46.2%,呈乙醇>乙酸>丙酸>丁酸;比较有机酸和乙醇的去除速率呈乙醇>乙酸>丁酸>丙酸,其中乙醇在产甲烷相中去除速率最快为0.21h^-1.系统运行稳定,COD去除率达到90%以上,其中对COD去除贡献率顺序为乙醇>乙酸>丁酸>丙酸,

Organic Acids Conversion in Two-phase of Immobilization Enzyme Acidfication and UASB,Anaerobic Reactor for Wastewater Treatment

Using immobilization enzyme acidification phase and UASB to produce methane phase as two-phase anaerobic fermentation process,the change characteristics and the change rate of organic acid and ethanol organic,composition and fermentation type as well as COD removal were studied.The experimental results showed that acidfication rate(VFA/COD) was consistently over 28.2%.The concentration of ethanol,acetic acid,butyric acid and propionic acid in acidfication-phase were 44.8%,38.4%,9.8% and 6.9%,respectively,as follow:ethanol>acetic acid>butyric acid>propionic acid.The removal of ethanol,acetic acid,butyric acid and propionic acid in methane production phase were 99.8%,92.0%,59.1% and 46.2%,respectively,and the removal of COD was higher than 90%.The conversion velocity of substrate in the methane production phase showed as follow:ethanol>acetic acid>butyric acid>propionic acid.The fermentation type of the acidification phase was ethanol-type fermentation.The effect of each acid and ethanol conversion on COD removal was as follow: ethanol>acetic acid>butyric acid>propionic acid.