A Canadian company is building a case for a greener, stronger concrete but is fighting resistance in the construction industry.
“The cement and the concrete industry is enormous worldwide. … And they do things a certain way and they have done those things that way for years and years and years,” says Barry Lester, chairman of Whitemud Resources Inc., which mines kaolin, a white-coloured clay, in southern Saskatchewan and turns it into metakaolin, which is used as a supplement to cement.
“To get people to consider making a change we are trying to turn the freighter, and it takes a long time to turn it,” Mr. Lester says. “That's the challenge that we are running up against.”
Between 90 million and 140 million tonnes of cement are produced each year in North America. Much of it is mixed into concrete that is then poured into commercial real estate projects where owners, tenants and building firms are becoming increasingly concerned with environmental standards. For every tonne of cement produced, about one tonne of CO2 is emitted.
As the industry debates green values and sustainability, Whitemud has spotted its opportunity to make a difference.
Whitemud says metakaolin is more durable than regular Portland cement, or any of the other widely used supplementary cement materials, and it is bringing it to market cheaper than previous suppliers.
It reduces greenhouse-gas emissions, saves time and money on the construction site and will make buildings and other construction projects last 100 years instead of 50 or 60, says Whitemud, which is based in Calgary.
“The only downside to metakaolin is inertia in the industry,” adds Mr. Lester, who helped to lead the engineering team for the Confederation Bridge, which links Prince Edward Island to the mainland. He was awarded the Canadian engineering leadership award by the Schulich School of Engineering at the University of Calgary in 2007.
“They have enormous environmental problems right now in the cement industry and we can help them with those problems,” he says.
The cement industry, however, has been working on becoming more green. In its 2008 sustainability report, the Cement Association of Canada says that, between 1990 and 2006, the industry improved its energy efficiency by 11 per cent and reduced the greenhouse-gas emission rate of production by 6.4 per cent.
“The industry is focusing efforts on further reductions through the introduction of supplementary cementing materials (SCMs) to offset the amount of clinker needed in the manufacturing of cement, and the increased use of alternative and renewable energy sources as a means to further reduce fossil-fuel consumption,” the report says.
Supplementary cementing materials (SCMs) are mixed with cement and reduce the carbon footprint of the finished product because they create fewer emissions than cement. Among the substances commonly used are fly ash, slag and silica fume.
Whitemud, with its kaolin mine at Wood Mountain, about 170 kilometres southwest of Regina, has 160 million tonnes of kaolin ore. It plans initially to make 200,000 tonnes of metakaolin per year and aims to increase production to 375,000 tonnes per year.
Metakaolin is an accepted SCM and has been used for decades, with the only supply in North America traditionally coming from manufacturers in Georgia and South Carolina. Those manufacturers supply the cement industry only as a sideline. Their primary market is making metakaolin – a fine, white powder – as a coating for glossy paper.It is also used in other products including paint, plastics, cosmetics and ceramics.
Whitemud, which was formed in 2005, has focused on how to make its product cheaper for the cement industry, while the manufacturers in the United States use a more intensive process to make the paper-grade metakaolin.
