I was wondering about this recently and found a fantasticTreehugger write-up on the issue.
I highly recommend reading the article (including comments) if you want the full scope. (Also, they’re a bit biased, but the Insinkerator folks have a fairly solid video detailing what happens to food waste when it goes down a garbage disposal).
Anyway, here are the key take-aways:
- Composting is always the preferred method to dispose of food waste. If you don’t have access to curbside composting or do not want to start & tend a compost pile in your backyard, I’d recommend trying a Naturemill.
Naturemill Indoor Composter: Arul’s brother recently purchased one (good work Bhu!) and I have to say it was pretty awesome. It’s small, fits in your kitchen, and churns / oxidizes food scraps so that they heat up and break down quickly… replicating the conditions of an industrial composting facility (full post on this product coming soon). - If you’re unable to compost (and really most folks who can afford a Naturemill should be able to), then typically, putting food waste down a garbage disposal is your next best option. There are two main benefits from using a garbage disposal as opposed to just placing food waste in the trash, including: 1) energy savings (less trucks hauling trash to landfills) and 2) reduced food waste in landfills (some of the bio-solids that end up in Waste Water Treatment Plants, WWPTs, are turned into fertilizer).
- Room for debate: It is important to note however that when food waste breaks down in an anaerobic environment (landfills & WWPTs are typically anaerobic environments), the food waste produces methane gas. There’s a stronger movement amongst landfills (relative to WWPTS) to re-capture that gas and prevent it from entering our atmosphere (where is it 21 times as potent as CO2). If you live in California, where methane re-capture is required for all new landfills, it may be better to have your food waste hauled to a landfill (though again – compost first).
