电刺激对餐厨垃圾-污泥共厌氧发酵产挥发性脂肪酸的影响

以小型生物电化学反应器为发酵装置，考察外加电刺激对餐厨垃圾-污泥共厌氧发酵过程中挥发性脂肪酸（volatile fatty acids，VFA）产量的影响。实验结果表明，餐厨垃圾协同污泥厌氧发酵，有利于体系中蛋白质和糖类的溶解消耗，提高VFA的产量。0.5 V微电刺激可增强厌氧体系中微生物的活性，有利于VFA的产出。第144和192小时，外加0.5 V的实验组VFA浓度分别为24 342 mg·L-1和21 291 mg·L-1，高于其他实验组，较空白分别提高了30.8%和4.1%；其组成主要是乙酸、丙酸和戊酸。发酵进行第24 h和96 h时，0.5 V微电刺激厌氧发酵体系中溶解性糖类和溶解性蛋白质分别为722.4 mg·L-1和1.49 g·L-1，且有机物水解酸化过程中，厌氧体系内糖类先于蛋白质被消耗。

Effect of electro-stimulation on volatile fatty acid production from anaerobic co-fermentation of food waste with activated sludge

The effects of electrostimulation on volatile fatty acid (VFA) production from anaerobic cofermentation of food waste and activated sludge were investigated using a bench-scale bio-electrochemical reactor. The results showed that carbohydrate and protein hydrolysis increased and higher VFA yields were obtained when food waste and activated sludge were used for anaerobic co-fermentation. The microorganism's activity was highest under 0.5 V direct electrical stimulation. Using this optimal condition, maximum VFA yields of 24.342 g·L-1 and 21.291 g·L-1 were achieved after 144 hours and 192 hours of fermentation, respectively, increases of 30.8% and 4.1% compared with the blank control. VFA composition analysis showed that acetic, propionic, and valeric acids were the prevalent acids. The concentrations of soluble protein and soluble carbohydrate reached 722.4 mg·L-1 and 1.49 g·L-1 after 24 hours and 96 hours of fermentation, respectively. This demonstrates that carbohydrates are utilized prior to proteins during anaerobic cofermentation.