Optimizing gas production in the anaerobic codigestion of the organic fraction of solid wastes from markets

This paper discusses the anaerobic co-digestion of sewage sludge from a wastewater treatment plant and the organic fraction of municipal solid waste (OFMSW) from markets (market waste). The organic fraction of market waste was obtained by means of a separate collection system. The laboratory set-up used was a batch system of anaerobic digestion with suspended biomass in mesophilic conditions, consisting of a series of glass digesters of 100 ml each in volume. The digesters were placed in a thermostatically controlled tank at 37±2°C: the biomass was kept in a state of moderate agitation. In order to evaluate the optimal co-digestion rate in terms of biogas production, six different ratios of sewage sludge to OFMW were studied, ranging from 100% to 0% in volume (as a percentage of sewage sludge).