Graymont and Fortera agree to make low-carbon cement at lime plants

Aug. 5, 2025 — Lime producer Graymont and startup Fortera signed a strategic partnership to make Fortera's ReAct low-carbon cement using Graymont's existing lime operations. Here's what happened, what it cost, and what went wrong.

Cost and outcome (as of Aug. 7, 2025)

Outcome: The agreement "provides for the construction and operation of a first of its kind plant" for ReAct "and lays a framework for the development of future plants at sites owned and operated by Graymont," according to Fortera's law firm. (Vinson & Elkins, Aug. 7, 2025)
Cost: Neither company disclosed a price, investment or schedule.
Claimed cut: Fortera says ReCarb produces cement with "70% lower carbon dioxide (CO₂) emissions" than ordinary portland cement while "maintaining near-term cost parity." (Fortera, ReCarb plant page)

What the companies said

The partnership "reflects years of product testing, design validation, and collaboration," the release says, and ReAct is intended for anywhere traditional cement is used "without compromising on durability or regulatory compliance." The companies say ReAct has had "over a decade of real-world validation." (Graymont and Fortera, Aug. 5, 2025 (PDF))

"They're not trying to reinvent the cement industry," said Graymont CEO Stéphane Godin. "Rather, they're working to innovate on the infrastructure we already have." Fortera CEO Ryan Gilliam said Graymont's choice "is a strong endorsement" and that "it's possible to cut cement emissions in an economic way." (Graymont and Fortera, Aug. 5, 2025 (PDF))

The companies say ReAct combined with Fortera's ReCarb process will let Graymont reuse CO₂ "without significant changes to its facilities or operations." Graymont says it has operated for more than 75 years across North America and Asia Pacific, and is the strategic partner of Latin American lime producer Grupo Calidra. (Graymont and Fortera, Aug. 5, 2025 (PDF))

How ReCarb works, per Fortera

Ordinary cement making heats limestone and releases CO₂. Fortera captures that CO₂ from kiln exhaust and mineralizes it into a reactive form of calcium carbonate, C&EN explained when the first plant opened in 2024. Fortera's plant page lists the steps: raw lime is dissolved with a proprietary solvent, carbonated in an absorber, separated, pressed and dried into powder. (C&EN, April 28, 2024; Fortera, ReCarb plant page)

Fortera's first plant, on CalPortland's campus in Redding, Calif., is rated at 15,000 tons a year of ReAct. Its brochure claims 9,600 tons a year of CO₂ savings: 6,600 tons captured in the product and 3,000 tons offset by energy savings. It says a 15% ReAct blend means 10% lower CO₂ per ton of blended cement. (Fortera Redding plant brochure (PDF); Graymont and Fortera, Aug. 5, 2025 (PDF))

Fortera describes the plants as a "bolt-on" to existing cement and lime plants that reduces capital spending, and says Redding is ISO 9001 certified. The brochure describes two products: ReAct Blend, meant to be mixed with cement to improve early strength and flow, and ReAct Cement, a white standalone binder made of a reactive calcium carbonate known as vaterite. It lists the plant as a 2024 BloombergNEF Pioneers finalist. (Fortera, ReCarb plant page; Fortera Redding plant brochure (PDF))

What went wrong

No site or date. The joint release doesn't say where the first Graymont plant will be, how big it is, or when it will run; those details appear nowhere we checked. (Graymont and Fortera, Aug. 5, 2025 (PDF); Vinson & Elkins, Aug. 7, 2025)
The 70% is the company's. C&EN reported it as what "the company says." We found no independent life-cycle assessment. (C&EN, April 28, 2024)
Blends cut less. In Fortera's own figures, the 15% blend the brochure says Redding will produce for the market cuts CO₂ by 10% per ton of blended cement, far below the headline 70% for ReAct alone. (Fortera Redding plant brochure (PDF))
What we don't know yet: the location, capacity and investment for the first Graymont plant.

Our follow-up question for Graymont and Fortera

Where will the first Graymont ReAct plant be built, at what capacity, and when will it start?

Sources

Graymont and Fortera, “Graymont and Fortera to Deploy Breakthrough Low-Carbon Cement Technology on a Global Scale,” Aug. 5, 2025 (PDF). graymont.com
Vinson & Elkins, “Vinson & Elkins Advises Fortera in Strategic Partnership to Deploy Breakthrough Low-Carbon Cement Technology,” Aug. 7, 2025. velaw.com
Fortera, “Fortera ReCarb® Plant in Redding, CA, USA” (web page), read Oct. 29, 2026. forteraglobal.com
Fortera, ReCarb Plant brochure, Redding, CA (PDF), read Oct. 29, 2026; brochure file dated Feb. 2026; it describes the Redding plant as of 2024. forteraglobal.com
C&EN (Matt Blois), “Fortera opens green cement plant,” April 28, 2024. cen.acs.org

Disclosure: [not in copy] Editor placeholder