by It is a major contributor to climate change — the way buildings and roads are made of concrete. It is also a growing problem as more of the world develops. So the race is on to find solutions for a material that is responsible for around 8% of global carbon dioxide emissions.
Now, one California startup has a technology that reduces carbon dioxide in cement manufacturing and may be able to operate on a large scale. Fortera intercepts carbon dioxide emissions from the kilns where cement is made and puts it back in to make more cement. In its first commercial-scale effort, the technology is being added to the CalPortland facility in Redding, California, one of the largest cement plants in the western US. It opens Friday.
“Our goal is to be a ubiquitous solution that can really work at any plant,” said Ryan Gilliam, CEO of Fortera.
Fortera will initially produce a lot with a blend with about a fifth of CalPortland’s product in a blend that reduces carbon by about 10%. Gilliam said there is strong demand for higher blends that reduce carbon by 40-50%, and for a pure product made by the company, which is 70% lower in carbon.
It is planned to move the first large bags out the door of the Redding plant the first week of May.
Fortera evolved in part from an earlier company called Calera that was among the first to convert carbon dioxide into cement starting in 2007. It poured about 100 tons of its low-carbon cement into office buildings and California sidewalks but closed in 2014 due to financial issues. challenges. Adding to that knowledge, Gilliam founded Fortera in 2019 with some former Calera employees.
There is “almost a cement plant every 250 miles in the world,” he said, and most are located near a limestone quarry. Because it works with existing plants and uses the same material already used by industry, Fortera says their technology is a cost-competitive option for rapidly preventing carbon emissions from warming the planet.
One difference from some other low carbon cement and concrete efforts is that it at least offers the possibility of being widely installed at cement plants instead of changing the way the industry currently runs.
Fortera’s is one of many efforts to reduce the climate impact of concrete. The American Institute of Architects educates many of the world’s largest architectural firms on carbon emissions from building materials.
Some jurisdictions including Vancouver, British Columbia have building standards that encourage low carbon concrete. California passed a law in 2021 that requires the state’s Air Resources Board to develop a strategy for the state’s cement industry to reduce its greenhouse gas emissions by 40% by 2035 and reach net zero by 2045.
The First Movers Coalition, an organization of more than 90 companies, has announced an initiative in 2021 to create greater demand for low-carbon cement through their massive purchasing power.
In the same year, 40 of the largest cement and concrete manufacturers announced a commitment to make concrete that does not contribute to climate change by 2050 through the World Cement and Concrete Association. They agreed to reduce emissions from cement, fossil fuel use in manufacturing processes and develop new ways to capture carbon.
Concrete is the second most used product in the world, after water. Cement makes up 10-15% of concrete by volume, but accounts for 88% of concrete’s significant emissions. Other ingredients in concrete are sand, gravel, crushed stone and water.
The manufacture of a tonne of cement emits almost one tonne of carbon dioxide. There was no simple replacement.
“The societal benefits of concrete are enormous … it is the backbone of modern society,” said Thomas Guillot, CEO of the World Cement and Concrete Association. Other materials sometimes fail to compete because they are not as durable, cannot withstand as much weight, or cannot withstand heat as well, he said.
HOW FORTERA 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 captures the carbon dioxide and pipes it into a machine where it is turned into a solid. The technology works at about 1,800°F (1,000°C), which requires less energy and emits less carbon.
When the captured carbon dioxide is mixed with calcium oxide, it turns into a type of limestone that becomes cement-like when wet. This product, which Fortera calls ReAct, is mixed with other ingredients to make concrete.
Fortera uses a 15% mix of ReAct in concrete as that is all that is allowed under existing industry standards governing material strength and durability.
The company is trying to find a product that is 100% ReAct approved as a substitute for cement and says that its test has shown that it can meet international requirements, but the regulatory process will take more than five years.
Some of the fastest growing cement consumers are in Southeast Asia and Africa, so global solutions are critical.
“The United States needs to do what it can and be a leader in helping other countries,” said Mike Ireland, president and CEO of the Portland Cement Association, the national trade association for U.S. cement manufacturers. “But we have to get the rest of the world, especially the Global South, as they industrialize to jump some of the technologies we had.
Carbon emissions from cement manufacturing are an “existential threat to the world and our industry,” he said.
___
The Associated Press’ climate and environmental coverage is financially supported by multiple private foundations. AP is responsible for each and every subject. Find AP standards for working with philanthropies, a list of supporters and covered areas of funding at AP.org.
