Life cycle inventory and mass-balance of municipal food waste management systems: Decision support methods beyond the waste hierarchy

Journal Article · Wed Nov 15 04:00:00 EST 2017 · Waste Management

DOI:https://doi.org/10.1016/J.WASMAN.2017.08.011· OSTI ID:22742187

Edwards, Joel ^[1]; Othman, Maazuza ^[1]; Crossin, Enda ^[2]; Burn, Stewart ^[1]

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1. Department of Chemical and Environmental Engineering, RMIT University, Melbourne 3000 (Australia)
2. Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn 3121 (Australia)

Highlights: • Life cycle inventory of 7 food waste management and treatment systems considered. • Energy balance notably different to a systems energy generation. • Food in-sink maceration shown to have volatiles reduced by 31% before digestion. • Mass-balance identifies recycling efficiency and product utility. • Increased landfill diversion confirmed to be critical for a lower emissions profile. - Abstract: When assessing the environmental and human health impact of a municipal food waste (FW) management system waste managers typically rely on the principles of the waste hierarchy; using metrics such as the mass or rate of waste that is ‘prepared for recycling,’ ‘recovered for energy,’ or ‘sent to landfill.’ These metrics measure the collection and sorting efficiency of a waste system but are incapable of determining the efficiency of a system to turn waste into a valuable resource. In this study a life cycle approach was employed using a system boundary that includes the entire waste service provision from collection to safe end-use or disposal. A life cycle inventory of seven waste management systems was calculated, including the first service wide inventory of FW management through kitchen in-sink disposal (food waste disposer). Results describe the mass, energy and water balance of each system along with key emissions profile. It was demonstrated that the energy balance can differ significantly from its’ energy generation, exemplified by mechanical biological treatment, which was the best system for generating energy from waste but only 5{sup th} best for net-energy generation. Furthermore, the energy balance of kitchen in-sink disposal was shown to be reduced because 31% of volatile solids were lost in pre-treatment. The study also confirmed that higher FW landfill diversion rates were critical for reducing many harmful emissions to air and water. Although, mass-balance analysis showed that the alternative end-use of the FW material may still contain high impact pollutants.

• OSTI ID: 22742187
• Journal Information: Waste Management, Journal Name: Waste Management Vol. 69; ISSN WAMAE2; ISSN 0956-053X
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
54 ENVIRONMENTAL SCIENCES
EFFICIENCY
EMISSION
ENERGY BALANCE
FOOD
LIFE CYCLE
MUNICIPAL WASTES
SANITARY LANDFILLS
SOLID WASTES