US-based C-Crete Technologies has published two independently verified Environmental Product Declarations (EPDs) for its clinker-free cement products, reporting cradle-to-gate carbon emissions of as little as 43.1kg CO2-eq/t – around 95 per cent lower than the 919kg CO2-eq/t reported in the American Cement Association's industry-average EPD for Portland cement.
The Type III EPDs, published through the National Ready Mixed Concrete Association (NRMCA), also cover a family of clinker-free and blended cement products with global warming potentials ranging from 129-187kg CO2-eq/t and 227-312kg CO2-eq/t, respectively.
California-based C-Crete said its proprietary technology eliminates the need for clinker production by activating natural minerals and industrial by-products into hydraulic cementitious binders. The products comply with the ASTM C1157 hydraulic cement standard and achieve compressive strengths of more than 5200psi (35.9MPa) after 28 days.
The company said its process can utilise a wide range of locally available raw materials, including limestone, basalt, pumice, slag, fly ash, recycled concrete and mine tailings, enabling decentralised production without high-temperature clinker kilns.
Founder and president Rouzbeh Savary said the technology was designed for global adoption by existing cement producers. "Because our chemistry runs on raw materials that exist almost everywhere, it's well suited to local, decentralised production rather than a handful of massive kilns," he said.
C-Crete added that its clinker-free binders are already being used in commercial concrete applications and said the technology is compatible with international cement standards that permit high levels of Portland cement replacement, including Europe's EN 197.
