« FDA Delay | Main | What I haven't been reading »
The World Without Us
To this day, nature hasn't come up with a microbe that eats it [a tire], either. Goodyear's process, called vulcanization, ties long rubber polymer chains together with short strands of sulfur atoms, actually transforming them into a single giant molecule. Once rubber is vulcanized -- meaning it's heated, spiled with sulfur, and poured into a mold, such as one shaped like a truck tire -- the resulting huge molecule takes that form and never relinquishes it.
Being a single molecule, a tire can't be melted down or turned into something else. Unless physically shredded or worn down by 60,000 miles of friction, both entailing significant energy, it remains round. Tires drive landfill operators crazy, because when buried, they encircle a doughnut-shaped air bubble that wants to rise. Most garbage dumps no longer accept them, but for hundreds of years into the future, old tires will inexorably work their way to the surface of forgotten landfills, fill with rainwater, and begin breeding mosquitoes again.
In the United Sates, an average of one tire per citizen is discarded annually -- that's a third of a billion, just in one year.
That is from Alan Weisman's truly excellent The World Without Us. Here is my previous post on the book.
Posted by Tyler Cowen on July 19, 2007 at 05:52 AM in Books | Permalink
Comments
I would seem like landfills could accept tires if they were sliced in half like a bagel. Then there would be no tendency to trap a donut of air.
Posted by: Slocum at Jul 19, 2007 8:30:59 AM
I thought all old tires became football fields these days...
Posted by: Amber at Jul 19, 2007 8:58:00 AM
They can be used to build coral reef.In Florida tires and ship were used that way
Posted by: JEAN at Jul 19, 2007 9:15:34 AM
In New York, I suppose that subways filling with water is marginally worse than exploding geysers of sewage.
Posted by: M. Hodak at Jul 19, 2007 9:19:25 AM
But did you know that old tires might help solve more problems than they create?
http://tinyurl.com/29ho6w
Posted by: Ironman at Jul 19, 2007 9:40:27 AM
Not so. The tire is not one large molecule. I doubt if there are any molecules in the rubber, over two million MW.
Posted by: Big Al at Jul 19, 2007 9:49:14 AM
Ironman -- I think the use of recycled tires in roads is even more extensive than this article suggests. The idea is being used a number of places for the sensible reasons cited in the article.
Posted by: ah at Jul 19, 2007 9:50:17 AM
the coral reef tires are a disaster! the ropes and cables holding them break and rust, and the tires go rolling along the sea floor destroying real coral reefs. Florida has a big project underway to remove them. link
http://www.npr.org/templates/story/story.php?storyId=11462066
Posted by: DK at Jul 19, 2007 10:36:08 AM
This company takes used tires and produces energy and a number of useful commercial byproducts.
Posted by: Jonas Cord at Jul 19, 2007 10:44:06 AM
Contra Big Al:
http://umassmag.com/winter_2003/One_Giant_Molecule_408.html
Posted by: PEmberton at Jul 19, 2007 3:50:34 PM
Why not cut them into smaller pieces and/or fill that empty space with compacted trash?
Posted by: Joe Grossberg at Jul 19, 2007 5:58:23 PM
Just put them all in one place, no big deal.
Posted by: Paul N at Jul 19, 2007 8:55:33 PM
Here's one rubber reclaim company:
http://www.gujaratreclaim.com/products.htm
And here's the patent on a rubber devulcanizing product:
http://www.patentstorm.us/patents/6590042-description.html
Posted by: KP at Jul 20, 2007 1:15:29 PM
As to cutting tires, it takes a surprising amount of energy.
As to landfills, I firmly expect that within the next 25 years as (a) robot tech improves, (b) energy costs stay high and (c) lechate contamination of groundwater becomes a growing issue, existing landfills will be mined down to bare earth and ongoing waste streams will be sliced and diced to a point that almost nothing gets landfilled.
Posted by: Francis at Jul 20, 2007 3:32:21 PM
This is a classic example of what happens when people don’t have access to the Internet. A very quick check of the web shows that
“In 2003, more than 290 million scrap tires were generated in the U.S. Nearly 100 million of these tires were recycled into new products and 130 million were reused as tire-derived fuel (TDF) in various industrial facilities. TDF is one of several viable alternatives to prevent newly generated scrap tires from inappropriate disposal in tire piles, and for reducing or eliminating existing tire stockpiles.”
See “Tire Derived Fuel” (http://www.epa.gov/garbage/tires/tdf.htm)
Properly run cement kilns work well with tires because the limestone absorbs the sulfur from the tires (forming gypsum, not CaS). Cement kilns also have high residence times (up to 10 seconds) and very high operating temperatures (up to 1500°C). Cement kilns aren’t perfect and exhaust gas treatment is still required (apparently).
See “Use of Cement Kilns in Managing Solid and Hazardous Wastes : Implementation in Australia” (http://ariic.library.unsw.edu.au/griffith/adt-QGU20050926-215906/). A useful quote
“The analysis of organic compound emissions indicated that extreme high combustion conditions in a cement kiln combined with high turbulence and long residence times readily overcome any oxygen deficiencies inside the kiln to achieve destruction efficiencies exceeding the 99.99% regulatory requirement and even reaching 99.9999% in many cases.”
See also “Cement Kiln” (http://en.wikipedia.org/wiki/Cement_kiln)
Could someone please provide Alan Weisman and Tyler Cowen with access to the Web so they could fact check what they write.
Thank you
Posted by: Peter Schaeffer at Jul 20, 2007 3:36:12 PM
Why would they want to bother with the facts when the blatherthon they're on is so much more profitable to them? And besides it can also amuse them to note the number of the credulous.
Posted by: Vanderleun at Jul 21, 2007 7:31:45 PM
I come from asia, injoy 室內設計,work in a 搬家公司,other enjoy isecosway和科士威,good see U。
Thanks.
Posted by: jack at Jan 6, 2008 9:38:56 PM
Most of these comments discreditng the obvious premise of Weisman's book fail to see the light. Our continued survival as a mamalian species will ultimately depend on how close we live within the laws of nature...we are not independent entities that can go on squandering energy and biodiversity to keep our gas tanks full and the artificial economy on a upward growth curve. Please read between the words-and you will realize that Weisman is unequivocally correct!
Posted by: bacteriocentric at Feb 3, 2008 2:31:16 PM
