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Concrete That Purifies the Air
fergus07 writes "Although much of the focus of pollution from automobiles centers on carbon emissions, there are other airborne nasties spewing from the tailpipes of fossil fuel-powered vehicles. These include nitrogen oxides (NOx). In the form of nitrogen dioxide it reacts with chemicals produced by sunlight to form nitric acid – a major constituent of acid rain – and also reacts with sunlight, leading to the formation of ozone and smog. Everyone is exposed to small amounts of nitrogen oxides in ambient air, but exposure to higher amounts, in areas of heavy traffic for example, can damage respiratory airways. Testing has shown that surfacing roads with air purifying concrete could make a big contribution to local air purity by reducing the concentration of nitrogen oxides by 25 to 45 percent."
Nitrogen oxides go into stone (if there is concrete evidence of this, har har) while nitrous oxide (N2O) gets you stoned.
...of course, someone will still confuse the two later in these comments.
So who owns the patent, how much extra does it cost, are there any materials not normally used in concrete that we should be concerned about.
With the way things are going, it will probably work out like this:
Monsanto owns the patent, it costs less than what we use now, but it has asbestos, and 10 years after installation if we don't treat it with a special chemical (patented by Monsanto) the asbestos is released spontaneously.
Out of modpoints but really liked a post? 1BDkF6TtmmeZ3yqXbz9yhdYVqRYnwFoXDj
ah its 10 % more expensive.
They're nice so long as you don't have any heavy weather, ground settling, or seismic activity. Then they go straight to hell and turn into the light version of Ice Crusher in Jet Moto, where you skip from slab to slab with a solid thump with each transition. Even in my MBZ it is enough to turn the stomach. The biggest problem with concrete is that you cannot repair it gracefully as you can with tarmac. If the ground settles under tarmac you plane the highs and fill the lows, then resurface a section of road (hopefully all lanes, but only the affected area in terms of distance.) If the ground settles under 'crete you grind the highs and pray. And if California is any indication, you probably cover it with some tarmac :p
You can get away with using them for speeds around 25 mph but even that is typically a tragedy. Just say no to concrete highways. Try to avoid using it in civil planning. Even the increased road glare is a hazard.
Anyone know how much CO2 is produced in the production of the concrete as compared to tarmac?
Side note: irony is a concrete company called tarmac. Fuckers did it just to confuse people.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
If you can put up with an uncomfy concrete floor in your bathroom you could save a fortune in the long run on matches and glade plugins.
So what happens to the roads after a few years when the nitrogen dissolves the road surface and you have to re-pave?
Uh..you re-pave? Was that a trick question?
Learning HOW to think is more important than learning WHAT to think.
This is an update on the results of the testing.
You're right. In fact, I saw this on slashdot in 2006.
My way is the highway.
Promote proofreading. Don't mod up sloppy posts.
Concrete is used all over the place air ie gas goes everywhere. Where there are cars and roads there are plenty of other places to use the air purifying concrete other than a road.
ah its 10 % more expensive.
That's big money in a road project!
You're thinking of phosphates. NOx causes smog.
I dug up the link to: http://science.slashdot.org/story/06/11/10/041214/A-Concrete-Solution-To-Pollution
Titanium is pretty common. The hard part with it is getting it into alloy form because it has to be smelted without oxygen present or else you get a bunch of titanium dioxide, a lit fart or two, and not much else.
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