Canada: An agreement has been struck between Lafarge Canada and Metro Vancouver in which Lafarge Canada will use the solids removed during drinking water production by the municipality as an alternative raw material in cement production.

The residuals are the solids removed during the drinking water filtration process and consist of natural sediment and elements from the source water as well as coagulants and polymers from the treatment process. Between them, they have a chemical composition similar to that of red shale, one of Lafarge Canada’s raw materials. This means that the residiuals need not be landfilled and that less virgin red shale must be removed from the ground. The contract is for a minimum of 10,000t/yr.

“We are proud to have this partnership with local government and industry,” said Pascal Bouchard, the plant manager of the Richmond cement plant, which will use the residuals. “These residuals will soon be part of our city landscape, reused as an ingredient in concrete that is used in construction, from sidewalks to skyscrapers. I am hopeful that the research we have undertaken will allow other municipalities to consider industrial re-use options for their water treatment residuals.”

“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. “Our goal is to recover valuable resources from our utilities, and this project aligns perfectly with what we are hoping to achieve.”