Organic solid wastes are generated in large quantities in Ecuador. In 2010, the whole production of municipal solid waste in Quito was estimated to be 1500 tons per day and the organic fraction represented about 60% of the solid waste. Landfills which are the most common disposal way of municipal solid waste in the country pose a threat to the environment and public health. Anaerobic digestion of municipal organic waste has shown to be a suitable option for stabilizing the organic matter and preserving the ecosystem and well-being of the population. In addition, the conversion of the solid waste into biogas and bio-fertilizer provides an alternative energy source and organic fertilizer with great potential for agricultural usage, respectively. In this research, the anaerobic treatment of fruit and vegetable waste (FVW) coming from a municipal market in Tumbaco was studied in laboratory scale semi-continuous bioreactors (4 L capacity). First, FVW was characterized to be used as a feedstock for AD process. Subsequently, the bioreactors were incubated with 10% weight of prepared anaerobic inoculum and fed with different concentrations of FVW to identify the optimal organic load. Prepared microbial inoculum was composed of 40% granular sludge obtained from an anaerobic reactor of a wastewater treatment plant in Quito and 90% (v/v) cow dung slurry (CDS). The mesophilic mixed digesters were fed with raw FVW in a semi-continuous mode with organic loads of total solids (TS) of 5, 7.5, 10 and 12.5% during 90 days in three different periods of FVW loading. The biogas production as well as the performance of the bioreactors was periodically monitored. The highest cummulative methane generation was achieved by the bioreactor fed with 5% FVW with a value of 2401.92 L CH4 kg VS-1. Finally, an effective technology based on AD was successfully developed as an alternative to landfills for the treatment of municipal organic waste in Ecuador.
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