The Hawaii Department of Transportation (HDOT) plans to use carbon-injected concrete in all future construction as part of its sustainable transportation initiative, according to Smart Cities. The material has been approved for “all flat work” such as roads and sidewalks.
According to the article, the concrete was produced using waste carbon dioxide. The carbon dioxide is mixed into the concrete and permanently embedded inside, which also improves material strength.
According to an article in Forbes, a company called CarbonCure makes technology for concrete producers that introduces recycled CO2 into fresh concrete. The CO2 is sourced from industrial emitters, according to the company. The technology can be retrofitted into existing concrete plants, and equipment injects the CO2 into a central mixer.
The end product is just as durable as regular concrete, without the high carbon footprint.
The use of carbon-injected concrete could reduce embodied carbon by 25 pounds per cubic yard, according to the article. One mile of concrete pavement uses about 21,000 cubic yards.
Source: Smart Cities, Khon 2, Forbes