Enhancement of Biogas Production throughPhase Separated Anaerobic Co-Digestionof Cattle Manure with Fruitand Vegetable Waste

In response to current energy challenges, anaerobic digestion (AD) is emerging as a viable and sustainable alternative to conventional fossil fuels.Phase separation evolves to mitigate process instability observed in single-stage AD, offering enhanced process stability and efficiency for biogas production.This study aims to comprehensively compare phase-separated and single-phase AD systems while incorporating cattle manure and fruit and vegetable waste (FVW) co-digestion to enhance process stability and biogas production.The two-stage and single-stage continuous AD systems were analyzed at an organic loading rate (OLR) of 3 gVSL -1 day -1 with a hydraulic retention time (HRT) of 10 days and three retention periods (30 days) under uncontrolled environmental conditions (20-35C), which may fluctuate with seasonal changes, and controlled temperature (37C).The FVW and cattle manure were co-digested in a 1:1 ratio of volatile solids (VS) as a substrate.The two-stage AD system operated at 37C and exhibited the highest biogas yield (0.25 NL/gVS) at a steady state as compared to single-stage AD, including 0.113 NL/gVS, 0.178 NL/gVS, and 0.201 NL/gVS at environmental