A research team at Purdue University is studying a way to combat carbon dioxide emissions from the second most used substance on earth, concrete, in half the amount of time.
Concrete production has doubled in the last 20 years, causing an influx of carbon dioxide (CO2) being thrust into the atmosphere. The material is a highly effective and useful building item, and as we reach a cycle in life on earth where building materials are constantly needed, that production will only continue to rise as time goes on.
Although shelter is necessary to survive the changes of mother nature, and concrete fills the gaps between surviving and succumbing to the elements, the energy used to produce concrete is quickly destroying the atmosphere, and is easily a large factor in climate change. The energy used to produce concrete emits more CO2 into the air than the aviation industry. Eight percent of the world’s CO2 emissions come from concrete production.
The process to make concrete starts with combining cement and water to make a paste, then mixing in aggregates such as sand or rocks. Other ingredients found in concrete might include silica, alumina, alkaline, and iron oxide. Over the years, as concrete sits as the base of a shelter or a skyscraper, it naturally pulls the CO2 from the air back into itself and traps it. This process does not occur quick enough to catch up with the amount of CO2 that is emitted during production.
Concrete substitutions have already been proposed, to avoid using concrete in projects. Steel, wool, bamboo. Wood, straw, hempcrete, recycled glass, and recycled plastic are just some of the many proposed alternatives. Some construction companies have already jumped on the idea of using these materials. Concrete can also be recycled. Abandoned buildings or properties that are on their way to be demolished are full of concrete that can be ground down and used again for another project. Reusing in any capacity always makes a positive impact on our planet.
In the case that alternatives do not work out, and concrete is still chosen by the builder, perhaps there is a way to change the components of concrete to help the earth rather than harm it. Even if concrete emitted less CO2 missions during the production binding process, the earth would see drastic differences in climate change and atmospheric conditions.
Assistant professor Mirian Velay-Lizancos leads the Velay Research group at Purdue University where two doctoral students were testing how small amounts of titanium dioxide mixed with cement affects samples of concrete. The research students noticed that the samples which contained the amounts of titanium dioxide were absorbing the CO2 in the air more efficiently than samples without.
With the natural process of concrete absorbing CO2 over time, adding micro amounts of titanium dioxide to cement mixtures would cut concrete emissions in half, which would double the absorption of CO2.
Although researchers have found a way to change concrete emissions, and that change will soon be brought to the construction industry, their goal is not to change the overall use of concrete, but rather mold the product to fit the needs of the earth.
With the mass production of concrete on the planet, emissions are polluting the air in drastic ways. While using concrete alternatives is not a new idea, changing the ratios in concrete mixtures is a step in the right direction.