Food waste (FW) has high production potential that can be converted into renewable energy in the form of biogas during anaerobic digestion (AD). Batch tests under mesophilic (37°) disgestion were performed to evaluate the effects of different dosage ratios (10-35%), salts (0-20 g·L-1) and oil content (0-20 g·L-1) on methane (CH4) production, process stability and organic reduction during the AD. The results showed that optimal CH4 occurred at a dosage ratio of 20%, while ratios > 30% caused inhibition. Salt ( 15 g·L-1 salt suppressed methanogenesis. Oil at 15 g·L-1 maximized methane yield (393.66 mL CH₄ production g VS-1) with 12-day digestion, while 20 g·L-1 oil induced inhibition. Excessive organic loading rate (OLR) (>3.0 g VS/L/d) triggered the accumulation of Volatile Fatty Acids (VFAs) > 20,000 mg/L and an acidification pH = 5.94, collapsing biogas production; recovery via pH adjustment, starvation, and sludge inoculation reduced VFAs by 96-100%, restoring stable biogas output (0.63-2.09 L/L/d) with neutral pH = 7.35 and 65% methane content. Microbial synergy and VFA degradation ensured system resilience under safe OLR ≤ 3.0 g VS/L/d, highlighting FW's viability for renewable energy recovery.
Ma et al. (Fri,) studied this question.