Currently, in Lane County, our landfill uses methane recovery to provide electricity for homes in this area. Our regional Wastewater treatment plant also uses methane to provide electricity to operate our plant. My question is, has anyone looked at the carbon footprint/energy consumption of curbside organic collection for composting versus landfilling (with methane recovery) versus encouraging the public to use garbage disposals to discharge food waste (not grease) via an existing infrastructure - wastewater collection and treatment system?
Sharon Olson
Technical Services Analyst
City of Eugene
United States
Curbside Organic Collection vs Garbage Disposal
Sign in or Sign up to comment
Sharon,
My understanding is that Marta is completely right. My husband is a waste water engineer, and he is often citing what a huge waste of energy it is to have the treatment plants dealing with food waste. I work in rural and agricultural planning, and I would also note that sending all that food waste to the waste water treatment plant or landfill also means that it gets contaminated with human waste an heavy metals or buried and lost as resource forever, when it could be composted into a valuable soil amendment: So another piece to the energy calculation is that somebody is putting a chemical based fertilizer on their field or garden rather than having access to inexpensive, quality municipally generated compost.
If this subject interests you, I'd suggest that you look into anaerobic digestion. This technology allows microorganisms to digest the food waste first, producing high quality methane, and leaving behind a waste that is easily composted into a high quality soil amendment. No one (in this country) is doing this yet on any sort of large scale, but I really think it is the next step in dealing with the 30% of our waste stream that is organic matter.
Nikkilee Carleton
Research Assistant
Muskie School of PUblic Service
United States
Sharon,
Although I've never done a study on garbage disposal use vs composting, I have worked with numerous wastewater treatment superintendents and they have all agreed that from a cost perspective, composting is a better way to dispose of the food materials that people put in garbage disposals. I am not aware of methane gas recovery from either operation (wastewater treatment or regional outdoor compost sites) I have heard of methane gas recovery from in-vessel compost but was under the impression this isn't a common practice.
You might find more information from a periodical called "Biocycle"
It is an interesting question. Please let me know if you reach a satisfactory evaluation method.
Marta Keane
[email protected]
Marta Keane
Recycling Specialist
Will County
United States