Enhance the biomethane yield of food waste by anaerobic fermentation

This research investigates optimizing food waste (FW) concentrations for enhanced methane production in anaerobic digestion (AD) systems. Various FW concentrations (10, 20, 30, 40, 50, and 100 % v/v) were assessed for their impact on methane yield, pH stability, volatile fatty acid (VFA) levels, and microbial community composition. The study found that FW concentrations up to 20 % v/v maximized methane production, achieving a peak yield of 140.20 mL CH4/gVS within an ideal pH range of 6.00-7.00. However, higher FW concentrations (>30 % v/v) significantly reduced methane output, with 100 % v/v halting production due to excessive VFA accumulation and pH drops. Key microbial players included acetoclastic methanogens like Methanosaeta and hydrogenotrophic methanogens such as Methanospirillum. These findings emphasize the importance of managing FW concentrations to maintain AD system efficiency, providing valuable insights into sustainable waste management and renewable energy production.