Biological assisted treatment of buffalo dung and poultry manure for biogas generation using laboratory-scale bioreactor

The bulk quantity of poultry manure (PM) and buffalo dung (BD) is generated by the growing poultry industry and buffalos in Pakistan that causes serious environmental issues such as air, water, and land pollution. Nutrient leaching, mainly nitrogen, phosphorus contaminates soil and water bodies, ammonia evaporation results in air quality degradation, and pathogen contamination affects the health of flora and fauna. This research study aims to utilize PM and BD for biogas generation to meet the energy requirement of the people and save the environment that was degraded due to improper disposal of selected waste. The anaerobic co-digestion technique was used for the treatment of poultry manure and buffalo dung. The ratio selected was 3:1, 1:3, and 1:1 in 500-ml glass bottles acting as digesters. The PM and BD were used in a separate digester. All the digesters have a retention time of 63 days and operated at a temperature of 37 °C and 45 °C. The detailed experimental work shows that 1:3 ratio of PM and BD yield 561 Nml/gm.VS. The quality of the biogas generated from 1:3 of PM and BD digester was also maximum among all five digesters; the volumetric composition of biogas obtained was methane 64% and carbon dioxide 32%. From this study, it was observed that the digestion of a single substrate is less productive as compared with co-digestion; co-digested substrate gives more quantity and quality of biogas, higher biodegradability of biomass, and effective volatile solids (VS) removal.