Purpose

To consolidate, disseminate, and gather information concerning the 710 expansion into our San Rafael neighborhood and into our surrounding neighborhoods. If you have an item that you would like posted on this blog, please e-mail the item to Peggy Drouet at pdrouet@earthlink.net

Thursday, December 5, 2013

Pollution-eating concrete?

http://www.columbiatribune.com/editorial_archive/pollution-eating-concrete/article_c82246f6-5cfa-11e3-9f03-10604b9f6eda.html

By Mike Szydlowski, December 4, 2013

Some of the fastest-growing jobs in the world deal with how to make technologies that do not to pollute the environment. There is plenty of research that shows more disease and illnesses in cities that have high pollution. It has always been a delicate balance between developing new technology and protecting the environment and health.

You might not consider concrete a new technology; however, in the case of this story, it most certainly is. The city of Chicago is testing the use of a new type of cement that is capable of removing pollution from the air. The concrete slabs can potentially reduce the levels of certain common pollutants by as much as 70 percent, depending on weather conditions and the amount of the new concrete used.

 This type of concrete is not really that new — it was developed in Italy to be used in and around the Vatican in Rome. Rome has very high air pollution, so officials wanted a type of concrete that would not become dull and dingy.

The concrete uses a chemical in the mixture that essentially eats away at the dirt and grime deposited on it. Although that is amazing in itself, scientists were very excited when they learned that the concrete also was able to clean the air around the pavement. Studies have shown that smog within 2.5 meters of the new concrete is able to be cleaned.

The secret behind this concrete is a chemical called titanium dioxide, which reacts with the toxic nitrogen oxide in the atmosphere and converts it into nitrates that simply wash away in the rain. These chemicals have not only turned ordinary concrete into a self-cleaning material but into an air-cleaning machine. This revolutionary type of material is called photocatalytic concrete.

Photocatalytic concrete could be the perfect paving material: It absorbs air pollution created by vehicles, reducing the amount to be inhaled by people. Italy and other areas of Europe have already paved many of their roads with the revolutionary material, but Chicago is reportedly the first city in America to try the new material out on a small number of their bike paths and roads.

The concrete could eventually become an integral part of the urban environment in this country, especially because the United States is notorious for its car culture, scientists explain.

So, why are cities not immediately pulling up their old concrete and replacing it with the new photocatalytic variety? Like any new technology, it is expensive to develop. This pavement is quite a bit more expensive than your traditional concrete.

As with many other technologies, though, as companies find ways to mass-produce this new material, the costs will decrease. Cities also will have to consider the amount of money that will be saved by not having to clean their buildings, artwork and streets. And it might not stop there. Other companies are developing products such as roof tiles with the same pollution-eating materials.

It is incredible that much of the world's air pollution problems could one day be solved by the exciting new technology … concrete!