16 October 2020, BATH, ON: Rio Tinto, Geocycle Canada and leading construction materials company Lafarge Canada are working together to reuse waste from the aluminium smelting process to make cement. In this circular economy initiative, the trio will reduce the need to extract other raw materials and create value from waste.
Geocycle Canada, a Lafarge Canada subsidiary, and Rio Tinto have developed a new product called Alextra, made from used potlining, as part of the aluminium electrolysis process that would otherwise go to landfill. 
Alextra is the result of years of research and development, aimed at finding new ways to deliver sustainable outcomes and value from used potlining. 
Lafarge Canada will produce on average one million tonnes of cement a year at its facilities in Bath, Ontario, using Alextra as an alternative to raw materials such as alumina and silica, which are commonly refined or mined for use in the manufacturing of cement. 
The companies will explore options to further expand the supply of Alextra from Rio Tinto’s Potlining Treatment Plant in Saguenay-Lac-St Jean to Lafarge Canada's network of cement plants.
Rio Tinto Aluminium manager valorization and marketing Stéphane Poirier said: "This partnership shows how Rio Tinto is innovating to find new ways to reuse waste, generating value from our operations and reducing their environmental footprint. We have worked closely with Lafarge Canada and Geocycle Canada over the past two years to develop a product that meets their needs and look forward to building on this partnership.”
Geocycle Canada senior manager Travis Smith explains: “As a global leader in building materials, we are committed to living up to the responsibility of helping to create a zero waste future. In order to achieve this goal, we need progressive partners such as Rio Tinto, and we look forward to what the future holds as we work to reduce our demand on virgin materials and deliver sustainable products.”
About Rio Tinto: Rio Tinto is the only primary aluminium producer in North America to process its potlining, an industrial residue from primary aluminium production, into an inert by-product.  The company’s Potlining Treatment Plant is capable of treating 80,000 tonnes of potlining per year from across Rio Tinto’s plants in North America and other producers. Rio Tinto invests in numerous projects to reuse by-products from its operations in Quebec. This summer, the company won the award Appel à initiatives 2020 from Québec Circulaire in the large business category, for its reuse of anhydrite, an industrial by-product used in the agricultural industry for its fertilizing properties and in the construction industry as a substitute for gypsum in the formulation of cement. 
About Geocycle Canada: Geocycle Canada, a subsidiary of Lafarge Canada, is a part of the global Geocycle network, which represents over 80 waste pre-treatment facilities and over 180 cement plants with dedicated co-processing installations. Geocycle partners with industries, service companies and municipalities to help them achieve their environmental commitments, by providing waste management solutions that are practical, economical and sustainable. Geocycle Canada applies the proven technologies of ‘pre-processing’ and ‘co-processing,’ and utilizes existing facilities in the cement industry to resolve waste challenges sustainably. This enables Geocycle to recover energy and recycle materials from waste, contributing to a regenerative, circular economy that closes resource cycles. Geocycle Canada operates facilities in British Columbia, Alberta, Quebec, Ontario and Nova Scotia, and some of its customers include many Fortune 500 companies. Last year, Geocycle Canada reduced the amount of waste going to Canadian landfills by more than 500,000 tons, thus making a tangible contribution to bringing societies one step closer to a zero-waste future.
About Lafarge Canada: Lafarge is the largest supplier of sustainable building materials in Canada and is part of the global LafargeHolcim group.With a workforce of 6,000 employees and 400 sites across Canada, Lafarge Canada's mission is to provide solutions that build better cities and communities. With cement, aggregates, ready-mix and precast concrete, asphalt mixes, paving and construction, we add value to every project.
Rio Tinto
Malika Cherry
M + 1 418 592 7293
Lafarge Canada
Jessica Assaf
M + 1 438 337 9142
Rio Tinto plc
6 St James’s Square
London SW1Y 4AD
United Kingdom
T +44 20 7781 2000
Registered in England 
No. 719885
Rio Tinto Limited
Level 7, 360 Collins Street
Melbourne 3000
T +61 3 9283 3333
Registered in Australia
ABN 96 004 458 404

SEPTEMBER 2020, VANCOUVER, BC: The North Shore Wastewater Treatment Plant (NSWWTP) is a new facility that will offer environmental benefits and additional community amenities in addition to its sewage treatment function. Located on Vancouver's North Shore, the facility is capable of treating 102 million litres/day under normal conditions and up to 320 million litres/day when storm water enters the sewer system in wet weather.

The new plant will be built to Leadership in Energy and Environmental Design (LEED) standards on a very compact site. With challenging conditions, including a location that had limited access with accelerated pour schedules, the Lafarge team was the ideal option to provide both performance and materials supply. The digester hopper, a portion of the plant, presented unique placing and finishing challenges. The pour was anticipated to take up to 16 concurrent hours. As well, the structure had to be watertight, with low shrinkage qualities in the concrete. The structure was built with dense rebar and formwork sections, with formwork installed during the pour. Therefore, the concrete had to set quickly in order to support the next lift. 

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Fortunately, Lafarge's WCAN Technical & Development teams - located across Western Canada - have the facilities, equipment, and expertise to develop custom mix designs that can meet these conditions and specifications. As a result, Lafarge provided a 14mm mix design that included a shrinkage-reducing admixture, successfully used in an earlier wasterwater treatment plant project. To further ensure that the accelerated mix utilizing our value added offering QuickSet had enough acceleration to support subsequent lifts, and to ensure there was no extra strain on the formwork during placing - Lafarge assisted in timed mockup samples to confirm performance.

The final product: a continual 28-hour pour that met the project's exacting specificiations, accommodated last-minute formwork changes, and value added offerings. Lafarge's combination of engineering capabilities paired with high performance materials ensured that the North Shore Wastewater Treatment Plant is anticipated to meet its LEED requirements utilizing a 50% SCM "Green" design for this structure, and assist Acciona in meeting its opening deadline.

À venir


Lafarge offre des solutions de rechange aux méthodes de conception normalisées qui permettent de maximiser l’utilisation de matériaux existants ou se trouvant sur place pour la réalisation de nouvelles routes ou pour la restauration de routes existantes. La stabilisation des sols au ciment constitue une possible solution permettant d’optimiser les propriétés techniques du sol afin d’améliorer la résistance, la stabilité, la durabilité, et le contrôle de l'humidité.

TerraCemMD est un mélange spécialisé constitué d’ajouts cimentaires et d’autres matériaux de construction couramment utilisés pour améliorer la résistance, la stabilité et la durabilité de la couche de base et(ou) de la fondation des routes.

TerraCemMD peut être utile pour l'assèchement, le compactage et la stabilisation du sol et peut réduire le risque de contraction-gonflement des argiles à forte plasticité, ce qui permet de transformer des sols qui autrement auraient été problématiques en matériaux parfaits pour la réalisation de la base et/ou la fondation d’une route. Une application bien faite améliore la résistance au cisaillement, la qualité de la fondation et réduit la compressibilité des sols cohérents et des matériaux granulaires.

Utilisations du TerraCemMD :

  • Construction de plateformes d'exploitation de puits de pétrole et de voies d’accès
  • Réalisation de base traitée au ciment lorsque les granulats sont rares
  • Valorisation intégrale des plateformes de chaussée existantes
  • Stabilisation de la couche granulaire
  • Stabilisation des sols contaminés
  • Mélange des sols profonds et coupés pour l’amélioration du sol
  • Assèchement du sol


  • Utilisation des matériaux sur place
  • Recyclage des plateformes de chaussée existantes
  • Optimisation de l’utilisation/réutilisation des matériaux, y compris les ajouts cimentaires
  • Économie d’énergie et des ressources naturelles
  • Performances supérieures dans des sols argileux
  • Liaison chimique des contaminants contenus dans le sol afin de réduire le lessivage


TerraCemMD est conçu pour rendre les sols conformes aux exigences particulières des industries de la construction des routes et du traitement des sols, mais ne peut être utilisé dans la fabrication du béton ou des produits en béton.

Les affirmations concernant les produits reposent sur une utilisation appropriée conforme aux normes de l’industrie reconnues. Veuillez communiquer avec votre représentant Lafarge pour des renseignements concernant les produits, la disponibilité et les commandes.