Coffee pulp - a potential source of energy

This research was undertaken to determine the optimum ratio of mixing coffee pulp, cowdung and old slurry for maximum methane production per volume of anaerobic digester. The parameters investigated were Nitrogen, Carbon, C : N ratio, potassium, phosphorous, protein, total solids, and volatile solids. Five 6 litre laboratory digesters with operating volume of 5 litre were tested for 10 weeks with cowdung and old slurry. Experimental observations indicated that methane production from raw coffee pulp could be enhanced by the addition of cowdung and old slurry of a biogas plant. The maximum gas production was obtained when the mixture of coffee waste, cowdung and old slurry was in the ratio of 3 : 1 : 1