The Household Use of Food Waste Disposal Units as a Waste Management Option: A Review

Municipal solid waste (MSW) consists of a high proportion of biodegradable matter, which when disposed to landfill decomposes leading to the formation of gas and leachate. Concerns over the environmental impacts of landfill emissions have resulted in efforts to identify alternative management options for MSW. Food waste constitutes a significant fraction of MSW, and its management presents considerable challenges due to its highly putrescible nature and the environmental, public health, and amenity implications. Food waste disposal units (FWDs) were introduced to the United States in 1927 as convenient and hygienic means to grind food waste at source and dispose of it directly to the sewer for treatment with wastewater. However, although FWDs are used in many countries throughout the world, their potential as a waste management option has not been fully considered. The authors review existing literature on the potential impacts of FWD use and investigate whether there are sufficient data to ascertain the sustainability of these units. Findings demonstrate that the use of FWDs is effective in reducing the amount of food waste disposed of to landfill. However, the impacts of their use on water consumption, sewerage system, and wastewater treatment processes require further investigation before this option can be accepted as a sustainable alternative to landfill.