Canadian Companies to Use Waste in Cement
Concrete is being mixed with the residuals of water filtration in Vancouver in order to address environmental impact concerns, as well as meet sustainability goals.
Lafarge Canada Inc., a concrete and aggregate manufacturer, and Metro Vancouver have brokered a three-year agreement, according to Lafarge, that involves using the residuals (left over from the filtration of drinking water) in cement manufacturing.
Residual Removal and Concrete Creation
During the water filtration process, solid residuals are removed, according to Lafarge. The chemical composition of these sediments—which are naturally occurring elements and treatment chemicals—forms something akin to red shale, one of the virgin aggregates used in the creation of concrete. These residuals take on a wet, clay-like appearance.
"Every year the filtration plant pulls between 8,000 and 10,000 tons of sediment and organic matter out of the water from the reservoirs," said Laurie Ford, Metro’s residuals management program manager, in an interview earlier this year.
After an initial successful trial period in May, Lafarge found that it could replace 2,100 tons of red shale, which the company would otherwise mine, with the residuals, and that the residuals did not create any emissions problems at the plant.
Prior to the trial, the Seymour-Capilano Filtration Plant would send 250 truckloads of water filtration residuals to the Vancouver Landfill every year. Instead, those same truckloads are now being sent to be part of the concrete manufacturing process.
The process means means fewer virgin minerals will need to be mined, and residuals will be kept out of landfills.
Company Agreement and Sustainability Goals
As part of LafargeHolcim’s Global 2030 Sustainability Plan, there is a call for the increased use of resources derived from the production of waste to be used in the company’s manufacturing processes. In the agreement with Metro Vancouver, Lafarge will produce a minimum of 10,000 tons of residual-added concrete per year.
“We are very excited to be working with Lafarge on this innovative project, which uses residuals as a product, while reducing our overall environmental impact,” said Darrell Mussatto, chair of Metro Vancouver’s utilities committee, in a statement. “Our goal is to recover valuable resources from our utilities, and this project aligns perfectly with what we are hoping to achieve.”