Abstract
The costs of food waste disposal systems, which were dried animal feed, composting, anaerobic digestion, and dryer-incineration, were evaluated from the perspective of global warming and energy or resource recovery. The method of an expanded system boundary was employed in order to compare different by-products. The life cycle costing was analyzed through the whole stages of disposal systems, which were discharge, collection, transportation, treatment, and final disposal, included in the system boundary. The costs and benefits were estimated by considering avoided impacts. Environmental benefits of each system for one tonne of food waste management were estimated based on the carbon price resulting from the greenhouse gas reduction and the price of by-products in a market. This study found that the costs for dryer-incineration scenario were the lowest followed by anaerobic digestion and the benefits of dried animal feed system were the highest. The B/C ratios were 0.26, 0.22, 0.11, and 0.27 for dried feed, composting, anaerobic digestion, and dryer-incineration respectively.