Cement = Climate Change =? As the world builds, expands and develops, cement is one of the key critical building components for this progress. This is true not only in developed economies like the US, but it is particularly true in the developing world, were cement is integral to the production of roads, skyscrapers, community housing projects, hospitals and schools. In fact, according to the New York Times, China, the world’s fastest growing economy, makes and uses 45% of the world’s output of cement. So sit back and join us as we look at a product that surrounds us all, but one we bet you have never paid too much attention to. Once we start making connections, we can start building solutions for many of the challenges we face.
Cement production is a process that creates a lot of pollution, from mercury emissions that are poisoning our air and water supplies to huge global emissions of carbon dioxide, the number one contributor to global warming. In fact, after power plants and oil refineries, cement plants are the largest producers of human caused greenhouse gases. Another challenging problem with cement, and one that should be, but may not be obvious, is that you can’t recycle it. Every time we build something new, we need to make new cement for it. We are however, coming up with innovative ways to reuse concrete, which reduces our demand for cement.
Did you know that cement is the main binding ingredient in concrete – so while these two words are often used interchangeably, they are not the same thing. Concrete contains sand and gravel that is mixed with cement to make a strong building material. There is a growing world market for recycled concrete, although too much of our used concrete still finds its way to landfills.
Lets get back to climate change. How does cement create carbon dioxide, the main cause agent behind human induced climate change? This happens in two ways: the chemical reaction needed to make cement releases a large amount of carbon dioxide, as does the huge amount of fuel required to heat the limestone, one of the main ingredients in cement production. Limestone is a huge “carbon sink” meaning it contains large amounts of carbon dioxide. This carbon dioxide is released when the limestone is heated to make cement, polluting the atmosphere and exacerbating the greenhouse effect, contributing to climate change. As well, the extreme heat needed in this cement creation process requiring huge amounts of fuel that release carbon dioxide as the fuel is burned; i.e. coal, oil, natural gas. These are the common fuels used in the heating process of cement production. Many communities, particularly in the US, are demanding that cement plants be retrofited with “cleaner” technologies to reduce their emissions, including using alternative fuels that are not as significant polluters as are these fossil fuels.
In the USA, good news came this past week from the Environmental Protection Agency, which under the Clean Air Act has the authority to tell major polluters to “clean up the air.” The EPA has put 100 cement kilns around the country on notice. They need to put new methods in place that will reduce current mercury and fine particle emissions by 92%! A huge step forward for healthier people, but the next necessary step is legislation requiring a healthier atmosphere and a reduction in global warming pollution!
People are beginning to “think outside the box” on cement, a substance that was invented back in the 1800’s. Many architects, builders, chemists and engineers are excited about finding new building materials to replace traditional cement and are looking at ways to make cement a “greener” product as well as a material that can be reused again and again.
This post was inspired entirely by Lisa Sharp of Retro Housewife Goes Green As part of the Green Moms Carnival, Lisa proposed the topic of cement, which stopped many of the Green Mom Bloggers in their tracks! But boy did we all learn a lot. As women concerned about the environment, the ubiquitous nature of cement fools you, but is something that we all need to make the connection to, and understand that there are significant and harmful effects for us all every time this common building material is produced. Look around as you travel about your daily life today, and consider all the places, products and structures that use cement as a base or as part of their construction.
So if you are putting in a new driveway, building a new foundation for your house, or voting on a new school or a new library-building project in your town, think about the building materials that might be used. Think about Lisa, who lives in a small town in Oklahoma where a cement factory spews pollutants daily into the air Lisa and her family breath. Think about the fight Lisa is fighting to clean up the air for her community, and think about what you can do to help her. Check out Lisa’s blog and read some of the fascinating posts that make up this month’s Green Moms Carnival. Learn about some of the alternatives to cement that are currently on the market.
Cement surrounds us yet is invisible. It is an integral part of all our daily lives. Yet its production is polluting our air and is a big contributor to changing our climate – the world over! Did you learn something new today? We did! Talk to the kids in your life. Ask them to look around and think about the places they visit and the products they use every day. Ask them to consider what these places and products are made of. We need to open our eyes and make connections, so the world we live in can be come healthier, stronger and more sustainable.