Author: Bill Corbett
Early results from groundbreaking industrial-scale research conducted by Lafarge Canada and Queen’s University Professor Warren Mabee show low-carbon fossil fuel alternatives produce significantly less greenhouse gas (GHG) emissions than conventional cement-plant fuel.
In a demonstration project at its Bath, Ontario plant, Lafarge replaced 10 per cent of its conventional petroleum coke and coal feedstock with old railway ties, asphalt shingles, packaging materials and construction debris, which normally would end up in landfills producing methane.
Research conducted at industrial-scale
“What’s really exciting about this project is it was done in a real industrial process, not at a laboratory or bench scale,” says principal investigator Dr. Warren Mabee, director of the Institute for Energy and Environmental Policy at nearby Queen’s University. “It’s a process that’s ready to be operational.”
The demonstration project is significant because Canada’s cement industry is responsible for some 3.8 per cent of the country’s carbon dioxide emissions, of which up to 40 per cent are due to fossil fuel use.
“Over the next five to 10 years, we’ll be seeing new carbon regulations,” says Robert Cumming, Lafarge Canada’s Manager of Environmental and Public Affairs. “The ability to use these low-carbon fuels will make our operations more environmentally sustainable and provide a competitive advantage in adapting to these new regulations.”
CMC one of funding partners
CMC Research Institutes provided $400,000 in funding for the $8-million, three-year project, spearheaded by Lafarge, Natural Resources Canada, the Ontario Centres of Excellence and Queen’s University, with partners including Pollution Probe, World Wildlife Fund Canada and the Cement Association of Canada.
Much of the funding was used to adapt Lafarge’s materials handling facilities and kiln to the use of surplus materials like railway ties, shingles and construction and demolition debris. The unusual nature of the fuels required rigorous, pioneering emissions testing and life-cycle assessments.
Drop in GHGs significant
Recently completed analysis shows these locally available, low-carbon fuels produced at least 50 per cent fewer equivalent GHGs than traditional petroleum coke, which must be imported. Because the cement-producing kilns already operate at 1450 degrees Celsius, there were no problems completely burning the disparate reused materials.
“It’s significant that in stack tests, carbon levels dropped significantly, with no tradeoffs in other emissions,” says Mabee.
Lafarge is awaiting provincial approval for the long-term use of these alternative materials. By early next year, it’s hoping to ramp up their use from 10 to 30 per cent of the cement plant’s fuel mix.
Bill Corbett is a Calgary-based journalist who writes about energy and carbon reductions