Field demonstration of the Reversa™ mineral carbonation process using natural gas flue gas streams at the National Carbon Capture Center, AL, 2024

Concrete, a mixture composed of a cementation agent, mineral aggregates, and water has the potential to serve as a gigaton-scale sink for carbon dioxide (CO₂). This could make concrete the world’s largest CO₂ utilization opportunity. CarbonBuilt’s Reversa™ process, developed at UCLA’s Institute for Carbon Management exploits simple acid-base chemistry to mineralize CO₂- dilute flue gas emissions into mineral carbonate-based cementation agents at ambient pressure, at flue gas temperatures, and without a need for carbon capture. The approach leverages innovations in the use of portlandite (Ca(OH)₂: calcium hydroxide, or slaked lime) which carbonates readily, and produces limestone (CaCO₃: calcium carbonate) – a potent cementation agent – upon its carbonation. Within the scope of a project sponsored by the US Department of Energy’s Office of Fossil Energy, the Reversa technology was upscaled and demonstrated using a modularized pilot-plant at the National Carbon Capture Center (Wilsonville, AL) using natural gas (~7-8.5 vol. % CO₂) flue gas streams. During the course of the demonstration, 31.34 tonnes of CMU, 51.31 tonnes of SRW and 40.06 tonnes of concrete manhole were produced and carbonated: (1) test carbonation process on ₃ separate concrete products, (2) produce >10 t/d of concrete of each product, (3) absorb > 0.2 gCO₂/g_reactant, and (4) ensuring compliance of carbonated concrete with industry standard specifications. The success of this demonstration suggests that the pioneering Reversa technology is ready for further product development commercialization.