Sometimes, it’s necessary to step back from a problem, then take a different route to its solution.
So if carbon dioxide (CO2) is a problem — which it is to the cement/concrete industry — you can try to produce less of the gas, or you can work instead to make it go away, sequestering it so it doesn’t escape into the atmosphere.
A start-up in Halifax, N.S. is doing just that. It has developed a system that means buying CO2 and adding it to strengthen concrete and speed its curing, while storing it away so it can’t escape.
Rob Niven is CEO and founder of CarbonCure Technologies, and he says the approach he has devised is to look at CO2 “not as a harmful gas, but as a value-added input in concrete production.”
CarbonCure licenses its process to makers of concrete block and pavers, and installs the necessary equipment in the licencees’ plants. Part of that equipment is a pressure vessel to hold the carbon dioxide the licensee must buy. So the licensee supplies the CO2; CarbonCure supplies the equipment and the know-how.
Food-grade CO2 is available from suppliers of industrial gases, but that pure form of the gas isn’t necessary. The CarbonCure process could use flue gas from power plants, but it’s not commercially available.
To support its sales efforts, CarbonCure developed environmental and health product declarations (EPDs and HPDs), and makes them available to its licensees. It was, said Niven, the first company in the concrete masonry field to do so.
It’s a move that others in the field are likely to be forced into.
Niven said that the declarations are “a prominent theme in the green building community and at green-building conferences.”
The company has about a dozen concrete block machines or production lines signed up, including Atlas Block, and Brampton Brick in Ontario, the Shaw Group in Atlantic Canada, Basalite Concrete Products on the west coast, Anchor in the American northeast and Northfield in the Chicago area. And by the end of the year, Niven said, “we expect to have 30 or more machines installed across North America”
“We’re just about halfway there already, and it’s only March, so we’re feeling pretty good about those numbers.
In the meantime, he said, his company is developing the technology necessary to broaden its reach beyond concrete masonry to the manufacture of “precast products . . . and into the much larger pool of ready-mix concrete.”
That is likely to happen later this year.
The company also talks from time to time about expansion off-shore.
“Interestingly, we’re seeing most (off-shore queries) out of China—not only producers, but investors and public-policy officials looking to address some of that region’s environmental concerns,” he said.
There are a lot of companies large and small working to address the problem of carbon in the concrete industry, and CarbonCure is just one of them.
“What I’ve found quite promising is that we tend to work together” Niven said. “I know the other CEOs, and we’re quite collaborative . . . while we compete with one another. That’s a positive thing.”
Among those he mentioned was Carbon8, a British firm that has developed a way to treat industrial wastes and contaminated soils. Their process speeds the carbonation process, sequestering CO2 in the process. It traps a variety of substances, including heavy metals, so they are made non-hazardous, and creates materials that can be used as a secondary aggregate.
CalStar Products, based in Minnesota, manufactures bricks, pavers, facing material and cast stone using a product that incorporates large amounts of fly-ash. The company says its manufacturing process uses 81 per cent less energy and 84 per cent less CO2 than conventional materials.
Although most of the company’s business is in the American mid-west, it has lately made inroads into southwestern Ontario.
BioMason takes a completely different approach to manufacturing masonry. It uses natural micro-organisms and chemical processes to “grow” brick.
The idea resulted from the skeletal structure of ocean corals, which are made from hard cementitious material created by nature with little energy use and low material inputs.
Its developer, Ginger Krieg Dosier, trained as an architect, but she has since become skilled in materials science and microbiology.