The Cement Industry is actively working to lower and eventually neutralize the CO2 output in the manufacturing process of cement. Championed in the West by the California Nevada Cement Association (CNCA), they are committed to “Achieving Carbon Neutrality in the California Cement Industry by 2045.”

Fortera is a pioneering materials technology company forging new ground in the effort, led and staffed by experienced industry executives. The scientists in the company have developed a technology that reduces carbon dioxide in the making of cement and has the potential to operate on a large scale. Fortera intercepts carbon dioxide exhaust from the kilns where cement is made and routes it back in to make additional cement.

Fortera evolved, in part, out of an earlier company called Calera that was among the first to convert carbon dioxide into cement starting in 2007. It poured some 100 tons of its low-carbon cement into California office buildings and sidewalks but shuttered in 2014 due to financial challenges. Building on that scientific knowledge, Fortera was founded by Ryan Gilliam, Ph.D., and Mike Weiss, Ph.D. along with several former Calera employees in 2019.

Compressive strength testing of the new concrete mix is conducted at Fortera’s facility in San Jose, California.

The Fortera ReCarb Plant is a turnkey, bolt-on decarbonization solution that integrates into existing cement plant infrastructures. In its first effort on a commercial scale, the technology was added in April to the CalPortland facility in Redding, California. Notably, CalPortland is one of the primary cement producers in the Western U.S.

Initially, Fortera will be producing its carbon dioxide-infused cement product, ReAct, to be blended with CalPortland’s product to reduce embodied carbon in the final product by about 10%. The first large sacks will move out the door of the Redding plant in late June – early July 2024.

Research Engineer Jesus Gonzalez Pequeño at work in Fortera’s San Jose, CA facility.

“Our target is about being a ubiquitous solution that can work really at any plant,” said Ryan Gilliam, Fortera CEO. Gilliam said there is a strong demand for higher blends that reduce carbon by 40% to 50%. ReAct, the CO2-infused product the company makes, has 70% lower embodied carbon than portland cement.

There is “pretty much a cement plant every 250 miles in the world,” Gilliam said, and most are located near a limestone quarry. Because it works with these existing plants and uses the same material the industry already uses, Fortera says its technology is an economically competitive option to quickly reduce carbon emissions.

A Fortera technician measures the addition of ReAct to the cement formulation.

One difference from some other low-carbon cement and concrete efforts is that Fortera can be installed widely at cement plants, versus changing how the industry currently manufactures cement.

How Fortera’s Technology Works
Cement manufacturers heat kilns to about 2,500°F (1,400°C} to break down limestone and separate it into carbon dioxide and calcium oxide.

Fortera’s process sucks the carbon dioxide out and pipes it into a machine where it is turned into a solid. Its technology depends on first manufacturing lime at around 1,800°F (950°C), which requires less energy and emits less carbon than portland cement that must be processed at about 2,700°F (1,400°C).

When the captured carbon dioxide is mixed with calcium oxide, it turns into a calcium carbonate mineral phase that becomes cement-like when water is added, much the same way portland cement is activated. This product, which Fortera calls ReAct, is blended with sand and aggregate to make concrete.

Fortera uses a 15% blend of ReAct in concrete as a start, because calcium carbonate addition at this rate is widely accepted under existing industry standards that regulate material strength and durability.

Sarah Plata, center, and Adiana Gutierrez, background right, at work in Fortera’s testing facility.

The company is working to get a product that is 100%-ReAct approved as a replacement for cement. Fortera says its testing has shown it can meet international requirements and, depending on the regulatory path selected, the approval process will take more than five years.

Graphics courtesy of Fortera; photos courtesy of AP Photo/Benjamin Fanjoy.