pH对果蔬、园林垃圾混合厌氧水解产酸的影响

EFFECT OF pH ON ANAEROBIC HYDROLYSIS ACIDIFICATION STAGE OF FRUIT AND VEGETABLE WASTES AND GARDEN WASTES

采用厌氧水解技术处理果蔬、园林混合垃圾,探究pH值对产酸效果的影响。在45℃、pH=6的条件下,第11天时反应器内消化液的挥发性脂肪酸(VFA)浓度达到最大值12.94 g/L,是未调控pH条件下VFA浓度的3.37倍,同时使达到最大值的时间减少了20%,大大提高了产酸效率。同时,调控pH可以促进溶解性有机物(SCOD)转化为挥发性脂肪酸,VFA/SCOD在pH=6条件下第11天时达到最大值,为48.73%。进一步对比分析不同条件下的消化液VFA组分和氨氮浓度,调控pH=6可使发酵类型从乙醇型发酵转为丁酸型发酵,也有利于蛋白质的分解。

In this study,fruit and vegetable wastes and garden wastes were treated with anaerobic hydrolysis technology,and the effect of pH on acid production was also discussed.At temperature of 45℃,pH=6,the volatile fatty acid(VFA)concentration of the fermentation liquor in the reactor reached the maximum value of 12.94 g/L on the 11 th day,which was 3.37 times the VFA concentration under the unregulated pH condition,and the time needed to reach the VFA maximum value was reduced by 20%,greatly improving the acid production efficiency.Regulation of pH could also promote the conversion of soluble COD(SCOD)into VFAs.The maximum VFA/SCOD value was achieved on the 11 th day under the condition of pH 6,was 48.73%,which was beneficial to subsequent utilization as a carbon source.By further analyzing the VFA component and ammonia nitrogen concentration in the fermentation liquor with different pH,the condition of pH=6 could change the fermentation type from ethanol type fermentation to butyric acid type fermentation,which was also beneficial to protein decomposition.