Effects of pH regulation methods on volatile fatty acids production through anaerobic co-digestion of waste activated sludge and citrus waste
The effects of different pH regulation methods on volatile fatty acids production through anaerobic co-digestion of waste activated sludge and citrus waste was investigated.By continuously adjusting the pH of the co-digestion system to 6,the solubilization process could be improved,processes of hydrolysis of carbohydrates,acid and methane production could be enhanced,VFA production and cumulative methane production were 1.36 and 1.25 times higher than those of the blank group,respectively;The abundance of hydrolysis bacteria and acid-producing bacteria was increased,which promoting the shift of methane generation pathway from acetyl decomposition pathway to hydrogenated nutrition pathway.By adjusting the initial pH of the co-digestion system to 10,the release of dissolved organic matter was effectively promoted,achieving rapid hydrolysis and enhancement of acid production performance,while the methane production process was inhibited.