In November 2022, the government of Canada published its Roadmap to Net-Zero Carbon Concrete by 2050, aiming to reduce the greenhouse gas (GHG) emissions of one of Canada’s most significant industries. Concrete in Canada is vast: the industry is responsible for approximately 158,000 direct and indirect jobs across the country while annually contributing $76 billion in direct, indirect, and induced economic impact to the Canadian economy.
In the roadmap, three specific goals are laid out as an action plan for the Canadian concrete industry: development of the Canadian market to adapt to a net-zero economy, innovation of the concrete industry via support for low-carbon technology development, and leveraging of export opportunities and international collaboration in order to establish Canada as a world leader in the low-carbon cement and concrete industry.
One of the main ways in which the roadmap’s report lays out a path to a net-zero Canadian concrete industry is through the re-evaluation of clinker and cement’s role in the production of concrete. Clinker is the main active ingredient in cement, comprised of calcium oxides and calcium silicates derived from limestone. This clinker is then combined with other materials to create cement, the binder in conventional concrete mixes.
The CO2 emitted when deriving calcium oxides from limestone in order to produce clinker, along with the fossil fuels burned in the process of heating clinker to produce cement, accounts for a major percentage of the GHG emissions from concrete manufacturing. In fact, the report notes that “cement production accounts for approximately 7% of GHGs globally. Cement accounted for 1/4 of all industrial emissions in 2019. In that same year, the cement manufacturing industry represented about 1.5% of Canada’s total emissions.
In order to reduce the concrete industry’s emissions, the government roadmap suggests the reduction of clinker in the cement mix, an increase in the use of alternative fuels in cement production, and the development of carbon capture, utilization, and storage (CCUS) technology in the sector. The roadmap indicates a $319 million investment into the research and development of CCUS technology, coupled with a tax credit for CCUS projects aimed at reducing GHG emissions. When the roadmap is followed, the Canadian government estimates 19.91 Megatonnes in cumulative GHG reductions from the 2019 level between 2020 and 2030.
Whereas the roadmap to net-zero focuses on the production of cement and the reduction of clinker in the cement mix, CarbiCrete has reimagined the manufacturing of concrete entirely. The CarbiCrete process is completely cement-free, indicating a 100% reduction in the GHG emissions stemming from the production of both clinker and cement. Instead of the conventional cement mixture, the CarbiCrete process makes use of steel slag, an industrial by-product. This steel slag replaces clinker-based cement as a binder in the concrete, leading to improved performance of the final product.
Not only does the CarbiCrete process reduce emissions by eliminating the need for harmful cement, it further sequesters CO2 within concrete by using CO2 to cure it. This permanently removes the CO2 even after the concrete is destroyed. The joint avoidance and removal of GHGs in the CarbiCrete process makes the resulting concrete cement-free and carbon negative, removing more carbon from the air than is emitted in its production. Large-scale adoption of the CarbiCrete process could not only greatly improve upon the roadmap’s timeline, but also set a global example beyond emissions reduction toward emissions negation.