Optimization of ultrasonication and alkalinization as pretreatment methods for leachate co-digested with food waste toward maximum synergistic effects

Anaerobic co-digestion (AcoD) of food waste (FW) and landfill leachate has shown promising results in enhancing the methane yield. However, leachate includes toxic and refractory compounds that may impact the decomposition process. In this research, co-digested leachate was pretreated using ultrasonication and alkalinization to manipulate its characteristics toward improved synergism with FW. Experimental optimization was conducted through biochemical methane potential (BMP) assays to identify the optimum operating conditions of the pretreatment methods. The study evaluated the synergistic effects of co-digestion with raw and pretreated leachate on enhancing the performance in terms of feedstock solubilization and methane production. The BMP test demonstrated that alkalinization and ultrasonication improved the total methane generation by 35% and 27%, respectively, yielding around 397 and 375 mL CH