Influence of pH and the insulation of reactor on the biogas production of livestock waste by batch anaerobic reactor

Abstract

This study presents the improved biogas production by determining the optimum pH and insulation reactor from cow, sheep, and poultry manure (which are the most available in our location). The experiment was carried out in 2000 mL digester put in the water bath at 37 ˚C. The mixing ratio of animal manure and water used was 1:1 in 12 days of Hydraulic Retention Time (HRT). Produced gas was measured by the volumetric water replacement method. The optimum pH will be chosen in the experimental test with different pH ranges in the first phase. Three set-ups were prepared with different pHs (6.5, 7, 7.5). The results showed that the pH had significant effects on biogas yield, where pH7 had the highest biogas production and pH 6.5 is the lowest. The second phase, investigated the effect of the insulation of the reactor on the biogas yield. The biogas was produced from an insulated reactor higher than the photoreactor because of the growth of algae which produces oxygen in the photoreactor. Therefore, it is given that the study which gave a maximum yield of biogas from the batch digestion process might be met the future energy demand.