Project Overview
Funded through ERA’s Industry Efficiency challenge in 2020, the Exshaw Low Carbon Fuels Project is a follow-on to the Cement Industry Low Carbon Fuel Implementation project, which installed a state-of-the-art alternative fuel receiving, storage and injection system at Lafarge’s Exshaw cement plant to replace up to 50 per cent of natural gas used in Kiln 6 with low-carbon, waste-derived fuels. The cement industry is a large emitter of carbon dioxide, accounting for nearly eight per cent of global emissions, and the system will enable significant emissions reductions in cement manufacturing while diverting large volumes of waste from landfills.
Using Construction Waste to Reduce Emissions from Cement Production
Emissions in the cement industry arise from the carbon emitted during the conversion of limestone and other minerals to clinker – the backbone of cement production – and from the use of fossil fuels in those thermal processes. In the Canadian cement industry, currently, over 90 per cent of fuels used are coal, petcoke, natural gas and other high carbon content fuels. To lower their carbon footprint, Lafarge introduced a state-of-the-art system at the Exshaw, Alberta, cement plant to replace a portion of natural gas used to power Kiln 6 with engineered low-carbon fuels sourced from construction demolition waste. The project installs a fully automated receiving, storage and conveying system that features enclosed tube belts, precision weigh-feeders, an advanced crane and comprehensive fire suppression systems. This system will enable consistent, high-volume co-processing of biomass-rich construction and demolition waste. The project represents a significant step for the cement industry, as many cement kilns worldwide struggle to maintain stable operations when using high-moisture, variable-quality waste fuels.
The project objective was to achieve a 50 per cent thermal substitution rate in Kiln 6 and reduce combustion emissions by using biogenic materials that would otherwise generate methane in landfills. The technology serves cement producers seeking deep decarbonization and waste processors needing high-value outlets for difficult-to-recycle materials. Expected reductions are about 30,000 tonnes of emissions each year, with cumulative reductions of 185,000 tonnes by 2030 and 785,000 tonnes by 2050. Early commissioning in 2024 delivered approximately 5,000 tonnes of emissions reductions, along with lower energy costs from displacing natural gas.
Ensuring a Smooth Ramp-Up Through Strong Design and Early Collaboration
The project consisted of two parts. First, the storage facility at the Exshaw plant received and stored materials, which included a fully automated 12-tonne crane to move alternate fuels from the receiving bay to storage hoppers. All alternate fuels are delivered by truck to the plant from Calgary in a “ready-to-use” state. Second, the alternate fuel was conveyed to the preheater tower via a series of enclosed material-handling equipment to reduce dust. The system utilizes a 300 cubic meter per hour tube belt that fully encloses the material between the new facility and the Kiln 6 preheater tower, where the fuel is injected directly into the calciner for co-processing.
During the project, Lafarge installed this full low-carbon fuel system and successfully commissioned the system in mid-2024. Construction took longer than expected because of unexpected ground conditions, high winds and the need for additional geotechnical work. Despite these challenges, the system ramped up quickly and reached the 50 per cent thermal substitution target almost immediately—much faster than similar projects at other plants—showing the value of strong design standards, careful commissioning, and close coordination with contractors and fuel suppliers. This rapid success also revealed another challenge; fuel suppliers were not yet prepared to deliver the full volume of low-carbon fuel needed. This highlighted the need to build strong partnerships with recyclers early and support them in scaling production. Overall, the project showed that early planning, strong technical design and tight collaboration across teams along the entire supply chain are critical to overcoming construction delays, ensuring smooth start-up and securing long-term access to the fuels needed to sustain emissions reductions.
What’s next?
After the project’s completion in 2024, Lafarge states the next steps for the project are to focus on increasing fuel supply, expanding fuel use, and continuing to reduce emissions at the Exshaw plant. Lafarge and Geocycle will work with Alberta waste processors to ramp up production of low-carbon fuels so Kiln 6 can consistently reach the 50 per cent thermal substitution rate. The team also plans to eventually inject biogenic low-carbon fuels into the main burner, increasing the overall thermal substitution rate to 80 per cent to further reduce emissions.