What type of study is this?

September 10, 2025

Factors affecting methane production and system recovery in mesophilic anaerobic digestion of food waste

Key Points

Optimal methane production occurred at a 20% dosage ratio during anaerobic digestion of food waste, with higher ratios leading to inhibition.
Salt concentrations less than 5 g·L-1 increased methane yield, achieving a peak of 314.75 mL CH4 production g VS-1 with 1 g·L-1 salt.
Oil concentration of 15 g·L-1 maximized methane production at 393.66 mL CH4 production g VS-1 while higher concentrations caused inhibition.
Excessive organic loading rates triggered volatile fatty acid accumulation, but recovery methods successfully restored stable biogas production.

Abstract

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.

AI से पूछें

Bookmark

View Full Paper