Abstract: The organic slurry from wet waste exhibits a “high carbon to low nitrogen”characteristic, making it suitable as an external carbon source to address the carbon-nitrogen ratio imbalance in leachate treatment plants. The experiment of hydrolytic acidification and stepwise filtration pretreatment of organic slurry was carried out in this study. The effects of pH, temperature, and hydrolysis acidification time on the preparation of acidizing fluid from wet waste organic slurry were investigated. The results showed that the optimal acid production conditions for acid production were temperature of 35 ℃, pH of 6, and a hydrolysis acidification time of 4 days, according to actual factors such as site, turnover cycle and economic costs, under which the concentration of VFAs reached 36 g/L, and the VS to VFAs conversion rate was 26%. Additionally, pH significantly affected the composition of fermentation products. At a moderate temperature of 35 ℃ and pH levels of 5.0, 6.0, and 7.0, butyric acid was the dominant product at the end of fermentation, followed by acetic acid and propionic acid. In the stepwise filtration experiments, it was recommended to pre-filtering the slurry using dual filtration with pore sizes of 1.0-2.0 mm and 0.2-0.5 mm, to prevent the rapid decline in membrane flux caused by ceramic membrane blockages.

Key words: wet garbage slurry, carbon source, pretreatment, hydrolysis acidification, stepwise filtration