Upgrading the biogas production from raw landfill leachate using O₃/H₂O₂ pretreatment process: Modeling, optimization...

Here, a combined pretreatment oxidation process (O₃/H₂O₂) was investigated to enhance the biodegradability of raw landfill leachate (RLL) and biomethane potential (BMP) in anaerobic reactors. The central composite design (CCD) and response surface methodology (RSM) were employed to optimize the operational parameters influencing on RLL bioavailability in O₃/H₂O₂ process: pH, Oxygen Flow rate, Reaction Time, and H₂O₂ concentration. The findings revealed that the O₃/H₂O₂ increased biodegradability index (BOD₅/COD) of RLL from 0.41 to 0.68 under optimized condition (pH=8, Oxygen flow= 0.25 L.min^-1, Reaction Time= 25 min, H₂O₂ concentration= 2.5 g.L^-1). Furthermore, the effects of O₃/H₂O₂ process on BMP of RLL were surveyed under mesophilic anaerobic reactors (Temperature: 37 ± 1 °C) in viewpoints of operational performance and methane yield in a batch mode for incubation period of 24 days. The results showed that O₃/H₂O₂ process simultaneously improve the BMP by 2.99 times higher in a shorter lag-phase period (5 days) compared with control. The pretreatment O₃/H₂O₂ and mesophilic anaerobic digestion process revealed a feasible and efficient method for enhance BMP of RLL.