QUANTIFYING THE GREENHOUSE GAS IMPACT OF PATHWAYS FOR TREATMENT OF SECONDARY RESOURCES GENERATED IN THE FOOD SUPPLY CHAIN

摘要

Food processors and retailers are under increasing regulatory and market pressure to manage their food waste in an environmentally responsible way. This study analyzes the climate change impacts of several alternatives available for the management of the several food wastes generated in this sector. Four food chain wastes are selected: whey, apple pomace, grease trap waste and bakery waste. Four treatment pathways were analyzed: landfill, anaerobic digestion, land application and animal feed. The results of the analysis showed significant differences among the pathways with climate change impact varying from -621 kgCO_2e/t to 1924 kgCO_2e/t. Landfilling of food waste resulted in the highest impacts and diversion to feed animals resulted in net benefits. The moisture content of the waste proved to be an important factor while the bio-degradability and nutrient value also had an influence. The combined impacts of diverting food waste from one disposal pathway to an alternative pathway were also considered and data is provided on the optimal pathways for each food waste alternatives.