Trash Talk

With all the recent talk of being “green”, many people have begun to make small changes to do their part. Living on my own I have vowed the same. Since I live in a duplex, without a yard, I am unable to compost so I have begun using my garbage disposal religiously.

Have you ever thought about how your garbage disposal works? Well, neither had I. Most people view their garbage disposals as being mysterious, you flip a switch and it works. That’s all most people care to know, though how a garbage disposals works is actually quite simple.

It is commonly thought that a garbage disposal works like a blender, with spinning blades chopping and breaking down the food. In reality disposals work in a different way and there are NO blades involved. Instead, impellers (or lugs) mounted on a spinning plate use centrifugal force, at a speed of almost 2,000 RPM, to continuously force food waste particles against a sharp-toothed inner wall. The wall breaks down the food waste into very fine particles, practically liquefying them. This process is most commonly interrupted, causing a jam, when the food placed in the disposal is either too large or too firm for the machine to handle. In these instances, the food will usually fall beneath the plate where it cannot be broken down properly. Keeping this in mind, large or firm pieces of food should not be placed directly into the disposal, but should first be broken down by hand into a workable size. Once pulverized, the running water flushes the particles through the inner wall, out of the disposer, and into your wastewater pipe. From there it flows into your septic system or to the wastewater treatment plant.

There are two common types of garbage disposals available that differ slightly from one another; continuous feed and batch feed. A continuous feed disposal operates, once switched on, by feeding food and water from the spinning plate to the inner wall and then finally to the drainage pipe. Batch feed disposals work in a similar way, except for the fact that a stopper is placed in the disposal. After loading a batch feed disposal, the stopper activates a switch which turns it on. Continuous feed disposals are considered to be more user-friendly, and are therefore more common, than batch feed disposals.

I hope you enjoyed learning about a little bit about your garbage disposal, but if you’re craving a bit more, here are some fun facts…
• John W. Hammes invented the garbage disposal in 1927 for his wife (apparently she didn’t want a vacuum cleaner). He spent eleven years refining his invention before starting his own garbage disposal business. The name of his company? The In-Sink-Erator Manufacturing Company.
• In nations with ready access to water and an industrial base, such as the United States, garbage disposals are common fixtures.
• In the US approximately 50% of homes had garbage disposal units in2009, compared with only 6% in the UK.
• Garbage Disposal Energy usage is not high; typically 500 to 1500 watts of power are used. This is comparable to an electric iron, but only for a very short time. Per year, this totals to approximately 3-4 kilowatt hours of electricity per household. Daily water usage varies, but is typically one gallon of water per person per day, comparable to an additional toilet flush.
• Food scraps range from 10 – 20% of household waste, and can be a problematic component of municipal waste. Burned in waste-to-energy facilities, the high water-content of food scraps does not generate energy; buried in landfills, food scraps decompose and generate methane gas, which is considered to be a potent greenhouse gas.
• The premise behind the proper use of a disposal is to effectively regard food scraps as liquid (averaging 70% water, like human waste), and utilize existing infrastructure (underground sewers and wastewater treatment plants) for its management. Modern wastewater plants are effective at processing organic solids into fertilizer products (known as biosolids), with advanced facilities also capturing methane for energy production.

References
Formisano, Bob. “Anatomy of a Garbage Disposal.” Home Repair. About.com. Web. 26 Nov. 2011. .
“Garbage Disposal: Facts, Discussion Forum, and Encyclopedia Article.” AbsoluteAstronomy.com. Web. 27 Nov. 2011. .
In-Sink-Erator Staff. “How Garbage Disposals Work.” InSinkErator. Web. 26 Nov. 2011. .
Larsen, Kurt. “How A Garbage Disposal Works.” Home & Garden Ideas. The Writers Network, 24 Feb. 2011. Web. 26 Nov. 2011. .
Vandervort, Don. “Home Tips : How a Garbage Disposal Works.” Home Tips. Web. 26 Nov. 2011. .