In January, Lauren Concrete officially announced its partnership with CarbonCure Technologies, a Canadian-based clean tech company that provides a solution to reduce the carbon footprint of concrete production. Carbon-Cure’s technology injects recycled carbon dioxide (CO₂) into concrete where it is mineralized and captured indefinitely, taking a harmful waste product and converting it to a useful additive. Lauren Concrete is proud to be the first in Austin, and in the state of Texas, to supply ready-mix concrete made with CarbonCure.
Lauren Concrete has installed four CarbonCure systems at four plants in Round Rock and Austin. The system consists of a pressurized tank of CO₂ connected to a valve box that controls the rate of injection into freshly mixed concrete. This valve box is linked with a command system connected to the batching software so that the injection of CO₂ is automated. Once injected into the concrete mix, the CO₂ undergoes a chemical reaction in the presence of water and cement, becoming a solid mineral similar to limestone and is permanently captured in the concrete. This simple setup has the potential to make a massive impact on global carbon emissions.
The advantages to CarbonCure are two-fold; the sequestering and recycling of CO₂ that would otherwise freely pollute the environment, and the opportunity to increase compressive strength. Studies have shown that the use of mineralized CO₂ in concrete improves its compressive strength, and this has been confirmed by extensive testing completed at Lauren Concrete’s facilities. Beyond increased compressive strength, no impacts have been observed on slump, set time, or other fresh or hardened concrete properties.
Eric Dunford, Director of Sustainability at CarbonCure Technologies, visited Austin, TX in March to discuss CarbonCure technology in-depth with interested partners, contractors, designers, engineers, and architects. For those who were not able to join the conversation, we put together a compilation of the frequently asked questions that we encountered during those meetings. Additional technical information is available on CarbonCure’s website at www.carboncure.com.
Q & A with Eric Dunford, Director of Sustainability at CarbonCure Technologies
Q: Will the injected carbon dioxide (CO₂) distribute amongst the load evenly?
A: Yes. The chemical reaction occurs very quickly (in a matter of minutes) and it is injected into the mixing process ensuring that it is distributed throughout the mix.
Q: Will the CO₂ have any adverse effects on admixtures that I normally use?
A: Extensive testing with a wide range of concrete mixes across North America has not revealed any incompatibility issues with any admixture or supplementary cementitious material available on the market today. There has been no effect from the use of CarbonCure with any known admixture. If you are using a new admixture that has not been used before additional testing may be warranted.
Q: Will customers still receive the same quantity of concrete that was ordered?
A: Yes, the same volume of concrete will be received by customers. Careful consideration is given to making sure the mix yields are the same regardless of any modifications.
Q: Just how much CO₂ will I be saving?
A: The exact quantity of CO₂ that a project will save depends on the concrete mix design. Generally speaking, the estimated average reduction of CO₂ is 25 pounds per cubic yard of concrete used.
