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The ability to inject carbon dioxide into concrete has existed for decades. But only within the past decade have parties begun to engage in such efforts to reduce greenhouse gas emissions and fight climate change.

Now, Vancouver, British Columbia-based CarbonCure has brought its carbon-sequestering technology to the Troutdale production plant of national concrete producer Knife River. Proprietary technology is used to inject recycled carbon dioxide into a given concrete mix, reducing the cement content correspondingly.

Following production of several test batches, the first field-grade batch of CarbonCure concrete was poured in February at Portland International Airport as part of the Port of Portland‘s Parking Additions and Consolidated Rental Car Facility (PACR) project. It’s being tackled by general contractor JE Dunn Construction.

鈥淭he Port was interested in what can we do that would be green on their project,鈥� said Scott Thayer, project manager for Portland firm Yost Grube Hall Architecture, which designed the project. 鈥淭he whole point of this is to reduce the cement content in the concrete. It’s one of the most carbon-intensive products in the world, especially in the amounts it is used and its prevalence in the world of construction. What’s beautiful about carbon is it’s a perfect substitute for the cement. It has similar strength-enhancing properties in the concrete mix.鈥�

Yukari Kubo, a design professional with YGH and co-chair of the firm’s sustainability committee, said the key to getting a large manufacturer like Knife River to jump on board was to specify use of CarbonCure.

鈥淚t takes the architects to specify it and bring it to the attention of the client,鈥� she said. 鈥淥ut here it just didn’t exist.鈥�

After calling concrete manufacturers on the East Coast, where CarbonCure has made more inroads, however, it was like talking to company representatives, she said.

鈥淭he only reason they don’t use it on every project is that the architects don’t specify it,鈥� she said. 鈥淚t’s a superior product.鈥�

The technology is a little more than 10 years old, said Kevin Davis, CarbonCure’s Pacific Northwest representative. But it has begun to enter the industry only in the past several years.

鈥淲e’ve been focusing on the concrete producers for the last four years, so people like Knife River are the type of firms we deal with,鈥� Davis said. 鈥淭hey supply a lot of concrete, and it makes a lot of sense.鈥�

CarbonCure uses processed industrial carbon dioxide captured at a British Petroleum oil refinery in Blaine, Washington.

鈥淚t’s the same as is used in soft drinks and beer,鈥� Davis said. 鈥淚t’s readily available, and we’ve developed a technology that injects it into concrete, recalcifies the cement and allows use of less cement and makes it stronger. It just takes a little bit of software and technology to implement.鈥�

Because the carbon dioxide replaces cement 鈥� the most costly ingredient of concrete 鈥� in a mix, the aggregate cost is reduced accordingly.

As climate change continues to gain attention, the technology is expected to attract interest, said Kelly Alexander, ready mix manager for Knife River’s Metro Division, which operates the Troutdale plant.

鈥淲e try and work with people like that to get the message out there,鈥� he said. 鈥淪o it’s our hope this won’t be the last Knife River plant we do, or the last in Portland. We make 3.8 million cubic yards a year, so there’s a tremendous opportunity to address most of this. We have the ability to impact production significantly across the state.鈥�

Alexander said YGH approached Knife River last year, made its interest in CarbonCure known and got the process rolling. By the time Knife River put in a tender for the concrete on the project, CarbonCure technology had been specified for bidders.

鈥淲e tend to get the technology integrated,鈥� he said. 鈥淪ometimes producers come to us proactively, and the other way is when someone like YGH specifies it into a project.鈥�

So far, San Francisco is a very strong market for the new technology, as well as cities on the East Coast.

鈥淚n general, yes, the coasts are good,鈥� Alexander said. 鈥淏ut we have a strong Midwest presence in Chicago, and we have pockets of business that tend to be around producers that have that sustainability message, and sometimes it doesn’t matter where they are.鈥�

Davis was on hand in Troutdale in February to oversee installation of CarbonCure’s technology at Knife River’s plant, as well as the first pours of footings and pile caps featuring the new mixes.

鈥淲e’ll take a standard mix that Knife River has and add CO2 to that directly,鈥� Davis said.

The company’s experience has shown the injection of carbon dioxide directly into a mix increases its strength by roughly 10 to 12 percent. But that’s only part of the equation.

鈥淭hey need concrete that’s delivered to specs, not necessarily stronger, so we reduce the amount of cement to allow them to achieve their PSI figure,鈥� Davis said. 鈥淚t achieves the design strength with less cement, and that’s what gives us the carbon reduction.鈥�

That’s the concept in a nutshell.

鈥淭he fact this hasn’t become the norm more quickly is a little bit surprising to me because it’s such a clear win,鈥� Thayer said.

It’s a huge advance for the entire industry, Kubo added.

鈥淎ll of the concrete manufacturers I spoke with on the East Coast were not charging any extra for it on any of their projects,鈥� she said. 鈥淚t is a fantastic technology and a game changer for our industry in terms of embodied carbon, which is what YGH is really focused on right now.鈥�