Sublime Systems carbonless concrete was first placed on a Boston-area construction project by contractor Turner and local ready-mix producer Boston Sand & Gravel.
Turner could not disclose the location of the building project where Sublime’s concrete was specified, but said it was in the greater Boston area and within truck-mixing distance of the BS&G facility where he produced
“It’s going to be in this building for decades to come,” says Leah Ellis, CEO and co-founder of Sublime Systems. “It was really a culmination of a lot of effort to see that it wasn’t just being done for testing, but actually replacing cement that would otherwise have been the carbon-intensive variety. That’s really satisfying to see.” .
Sublime’s concrete cement is produced using a process developed at the Massachusetts Institute of Technology and pioneered by Ellis that uses electrochemical processes to make powdered cement. Instead of heating limestone and clay mixed with iron ore or fly ash in a kiln up to 2,700°F, Sublime’s cement-making technology can be powered by renewable electricity, and its processes allow electrons break down the ingredients at room temperature. Sublime’s other co-founder, MIT professor Yet-Ming Chiang, is involved in a similar technology startup, iron-air battery producer Form Energy.
“This change in the way you define cement really allows you to adopt innovative products that might not be made in a fossil fuel kiln that gives you a certain crystalline composition,” Ellis says.
David Robb, Turner’s estimator and preconstruction project manager for the Boston area, said there was nothing out of the ordinary about the concrete placement on the project and that the material provided by BS&G with Sublime’s cement it was tested for temperature and drop when it arrived on ready trucks just as it would have been on any other project.
“In the grand scheme of things, it was really, really boring to build,” says Robb. “But it’s a big step toward our carbon reduction goals that we’re striving for going forward here at Turner.”
He says the seven-day breaks in carpet placement brought it back online on the strength of the intended design.
Robb was looking into technologies like cement from Sublime Systems as part of Turner’s corporate embodied carbon commitment and heard about the company in mid-2023.
Turner has a self-executing concrete group and Robb asked local project managers to let him know of any good opportunities to pilot a product with Sublime cement. In late January, a mud carpet placement came together on a job with Turner acting as the concrete contractor and Boston Sand & Gravel as the vendor.
Ellis says Sublime provided its cement products to Boston Sand & Gravel, which mixed them to the required tolerances and shipped the material in trucks where it was pumped 200 feet.
“We had an opportunity for a low-risk placement,” says Robb. “These guys were thrown into the gauntlet on a cold January day pumping their gear.”
