Sustainability Evaluation of Food Waste Management Techniques

The storage, preparation, and consumption of food all contribute to the generation of food waste. The optimal food waste management method is a contentious issue and depends on multiple factors. At a minimum, policy makers should consider the environmental, economic, sociopolitical, and operational impacts of different food waste disposal methods. This analysis estimated the relative costs, carbon footprint, space footprint, labor demands, diesel fuel demand, electricity demand, and water demand of different residential food waste management methods. The food waste management methods were: disposal in a landfill operating with landfill gas collection and power production (Landfill), source-separated food waste collection and centralized composting (Compost), food waste disposal through kitchen grinders and sewer conveyance to a municipal wastewater treatment plant (WWTP/Sewers), source-separated food waste hauled to a municipal wastewater treatment plant and added directly to an anaerobic digester (WWTP/Hauled), and organic waste recovery from a mixed material recovery facility followed by hauling to a municipal WWTP anaerobic digester (Mixed MRF). A brief discussion of many qualitative issues associated with each food management method is also included. The focus of the research was on residential food waste generation and does not apply to commercial or industrial food waste generation.The Landfill alternative showed the highest biogenic and total CO2e emissions, while the WWTP/Hauled alternative showed the lowest non-biogenic and total CO2e emissions. The WWTP/Sewers alternative had the highest capital cost, but the operating costs were the lowest, thus the present worth was also the lowest. The largest space footprints were required for the compost facility, landfill, and MRF alternatives. The largest potable water demand was for the WWTP/Sewers alternative as a result of flushing water demand to convey food waste through the food waste processor and sewers.