Cu^(2+)对有机废物联合发酵产乳酸的影响  

Effect of Cu^(2+) on yield of lactic acicd from oganic waste fermention

作　　者：张婷[1] 李君[1] 张文娟[1] 李响[1] 刘亚男[1] 

机构地区：[1]东华大学环境科学与工程学院,上海201620

出　　处：《环境工程学报》2017年第8期4701-4707,共7页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金资助项目(51508084;51578122);上海市扬帆计划项目(15YF1400800)

摘　　要：利用剩余污泥和厨余垃圾2种有机废物联合发酵,研究了在pH 7.0,温度为35℃,Cu^(2+)投加量分别为0、20、40和100 mg·L^(-1)时,乳酸的含量及其手性的变化规律。同时,探讨联合发酵过程中多糖、蛋白质、氨氮、VFA和pH与乳酸的变化关系。结果表明Cu^(2+)在低浓度时可以促进乳酸的产生:当投加量为20 mg·L^(-1),发酵第3天总乳酸最高浓度为23.22 g·L^(-1),较空白提高了77.06%,其中L-及D-乳酸浓度分别达到6.95 g·L^(-1)和16.27 g·L^(-1)。随着Cu^(2+)含量继续提高,总乳酸产量随之下降:在Cu^(2+)100 mg·L^(-1)时,乳酸最高浓度下降至16.55 g·L^(-1),获得最高值的发酵时间滞后至第6天。响应面分析表明,发酵体系中D-乳酸的光学纯度随Cu^(2+)投加量整体呈上升趋势。深入研究发现,适量Cu^(2+)在厌氧发酵体系过程中促进了多糖和蛋白质的溶出水解速度,从而提高了酸化的发酵潜力。Fermentation of waste activated sludge and food waste for lactic acid production was conducted at pH7. 0 and 35 ℃. The effect of Cu^2＋dosing at concentrations of 0,20,40,or 100 mg·L^-1on L-and D-lactic acid was investigated. In addition,the relationship between the concentration and optical purity of the lactic acid,and the variation of soluble carbohydrate,protein,ammonia,VFA,and pH was elaborated. The results showed that the addition of Cu^2＋at lower dosage could promote the production of lactic acid. When Cu^2＋was dosed at 20 mg·L^-1,the concentration of total lactic acid increased up to 23. 22 g·L^-1on the 3rdday,which was a 77. 06% enhancement（ the highest）,compared with the control test. The L-and D-lactic acid production reached 6. 95 g·L^-1and 16. 27 g·L^-1,respectively. However,decrease of lactic acid production was caused by a higher dosage of Cu^2＋. When Cu^2＋content was controlled at 100 mg·L^-1,a significant lag phase for lactic acid accumulation（ which reached 16. 55 g·L^-1） was observed for up to 6 d. The response surface illustrated that the optical purity of D-lactic acid increased with increase of the Cu^2＋dosage. It was found in this study that Cu^2＋has a significant effect,which could explain the improvement of dissolution and hydrolysis of carbohydrate and protein. Thus,the potential for fermentation of lactic acid and VFA from organic waste was promoted by the appropriate addition of Cu^2＋.

关 键 词：乳酸 有机废物 CU2+ 发酵 

分 类 号：X705[环境科学与工程—环境工程]