Optimization of Operating Parameters for Two-Phase Anaerobic Digestion Treating Slaughterhouse Wastewater for Biogas Production: Focus on Hydrolytic–Acidogenic Phase

In a two-phase anaerobic digestion process, enhanced biogas production and organic pollutant removal depend on the stability performance of hydrolytic–acidogenic methanogenic phases. Additionally, phase is rate-limiting step, which calls for further optimization operating parameters. The objective this study was to optimize parameters reactor (HR) in treating slaughterhouse wastewater. experiment carried using bench-scale sequential bioreactors. were optimized six different hydraulic retention times (HRTs) (6–1 day) loading rates (OLRs) (894.41 ± 32.56–5366.43 83.80 mg COD/L*day). degree hydrolysis acidification mainly influenced by lower HRT (higher OLR), highest values 63.92% 53.26% at an 3 days, respectively. findings indicated that, steady state, concentrations soluble chemical oxygen demand (SCOD) total volatile fatty acids (TVFAs) decrease as decreases OLR increases from HRTs 1 day 894.41–1788.81 COD/L*day, respectively, increase 6 4 days. concentration NH4+-N ranges 278.67 369.46 mg/L, not range that disturbs hydrolytic acidogenic reactor. It concluded days ORL 1788.81 COD/L*day selected optimal conditions high wastewater mesophilic temperature. can be applicable other agro-process industry types with similar characteristics biowaste value addition sustainable management safe discharge.