Abstract:In order to evaluate the anaerobic digestion performance of fresh leachate from landfills and explore measures to enhance its anaerobic digestion performance, low, medium, and high food to micro ratios (0.49, 1.02, 1.92g leachate COD/g sludge VS, respectively) were used. The effects of adding<5 µ m, 75-150 µ m, 2-5mm charcoal, and 75-150 µ m bamboo charcoal on the anaerobic digestion process of leachate were compared at high food to micro ratios The results showed that the methane conversion of leachate was severely delayed and unstable during high food to micro ratio At high food to micro ratio, compared with the control group without biochar, the charcoal group with<5 µ m, 75~150 µ m, 2~5mm, and bamboo charcoal group with 75~150 µ m increased the methane production rate by 179%, 93%, 83%, and 64%, respectively. The dissolved nitrogen in the final effluent decreased by 21%, 16%, 16%, and 12%, and NH 4+- N decreased by 17%, 12%, 10%, and 8%, respectively; And the degradation of organic matter and organic acids, especially butyric acid and acetic acid, in charcoal groups with a particle size of<5 µ m is significantly faster than in charcoal groups with other particle sizes These results indicate that biochar can improve the anaerobic digestion efficiency and process stability of leachate. For charcoal, the smaller the particle size, the more significant the effect.