A Canadian company is hoping to make the concrete industry greener with new technology that allows the product to store carbon dioxide (CO2). Nova Scotia-based CarbonCure, after success with CO2 infused concrete masonry blocks and poured concrete, has developed a method to introduce CO2 into the mix during production via a retrofit at plants.
The CO2 gas is sourced from the smokestacks of industrial emitters. Then it is chemically converted into solid calcium carbonate, essentially limestone, which is permanently embedded within the concrete. When the concrete structure is demolished and pulverized, the gas won’t escape – because it no longer exists. According to the company, a typical building project made with CarbonCure concrete products may reduce as much CO2 as an acre of forest will sequester over the course of a year. Already some of the giants of the industry are taking notice. Vulcan, America’s largest producer of construction aggregates announced the industry’s first ready mixed license with CarbonCure. The installation of the CarbonCure technology in Vulcan’s ready mixed concrete facility in Virginia means that Washington, D.C. will be the world’s first metropolitan market with access to the sustainable concrete.
The product is also starting to be used in Canada. A Halifax building site where the new Ambassatours corporate and bus service centre is under construction is one of the first projects to use it. Scott Biggar, sustainability manager for CarbonCure, said there are a number of forces in the construction industry that could make green products like CarbonCure more desirable in the coming years. New Prime Minister Justin Trudeau has made it clear at the Paris climate change summit this month that he intends to make Canada a leader in carbon capture and sequestration technology to reduce the country’s impact on the environment. And various provinces, like B.C. and Alberta are in the process of releasing or implementing climate plans. And LEED v4, which is expected to start in a year or so, will bring a lot of changes, including an emphasis on building materials.
"There’s really going to be focusing on carbon footprint of materials, life cycle assessment of every little thing that goes into the building," Biggar said. However, Biggar noted that there’s no silver bullet when it comes to dealing with climate change. Addressing it will be the result of focusing on lots and lots of little things and sequestering CO2 in concrete is just one of them. "You need to address every little pocket to make it better," he said. The company has retrofitted about 21 concrete block/masonry plants in North America and has begun doing retrofits for the ready-mix industry.