| Anaerobic digestion of municipal solid waste enriched with waste secondary sludge has been accomplished at solids concentrations of 20 to 40%. By utilizing the waste near its original solids level, handling and water requirements were minimized. Valuable end-products of methane and compost were obtained.; Experimental work involved the anaerobic digestion of a synthetic municipal solid waste (MSW), made using high newsprint content and food waste, supplemented with waste sewage sludge (WSS). The responses measured were biogas productivity, percent methane, total solids and volatile solids, alkalinity, pH, and volatile fatty acid concentration. This study was undertaken to determine the optimum temperature, solids level, and MSW:WSS ratio for a high paper content North American waste and to gain a further understanding of the effects of various operational variables.; Dry anaerobic digestion was successful at solids levels beyond 20%. Optimum biogas production rates were realized in thermophilic digesters. Mesophilic digesters with same operating parameters, were more stable in operation but yielded 30% less biogas. Optimum operating parameters found in this study were solids concentration of 30 to 35%, longer retention time of 21 days, and a MSW:WSS ratio of one. |
