Experimental investigation of the effective parameters to improve process for biogas production from food waste and its energy analysis

An experimental investigation has been done on the effective parameters on biogas extraction from the combination of food waste (FW) and cow manure and organic. Samples of FW were collected from the university restaurant and they mixed with the manure with different ratios of 1: 1, 1: 2, 1: 3, 3: 1 in a 1 liter polymeric bottles. These bottles embedded in a hot water bath at a thermophilic temperature of 55-60 ° C in a period of 15 days. The volume of biogas produced was measured. The results of gas production showed that the ratio of 1: 1 obtained the highest volume of cumulative gas ( 5 liters). Ten grams of chemical additive of silica gel and organic additives like rosemary plant, walnut shells, banana and tomato skin were added to the optimum selected ratio of digester. The produced cumulative biogas was increased 24.4%, 7.2%, 2.3%, 1.9%, 6.6% by volume respectively in compare with that of optimum based mixture. During the digestion period, PH changes showed that the highest volume of biogas was generated in neutral pH. And the use of walnut shells resulted in PH stabilization in the process. Measuring thermophysicsl properties (Total solids, volatile matter, moisture content, ash content), for the mixture of food waste and manure were shown the high capacity of food waste to convert to biogas (43%) Based on the laboratory experiments, energy analysis was performed for portable biogas reactor.