FMRG: Eco: CAS-Climate: Reimagining Cement Manufacturing for Carbon Neutrality (NeutraCEM)

Portland cement is the primary binding agent in billions of tons of concrete used every year for construction of nearly all forms of physical infrastructure. Its worldwide production, amounting to 4.5 billion tons per year, is responsible for ~8% of anthropogenic carbon dioxide emissions and ~25% of all industry carbon dioxide emissions. Cement manufacturing is among the hardest industries to decarbonize because the carbon dioxide emissions are unavoidable results of essential chemical reactions (e.g., decarbonation of limestone to produce lime and carbon dioxide) and high-temperature processes powered by carbon dioxide -intensive combustion of fossil fuels.

As the U.S. embarks on a once-in-a-century infrastructure revival program, while also committing to slash carbon dioxide emissions by >50% by 2030 (to limit global warming to 1.5 degree Celsius, as per the Paris Agreement), there is an urgent need to disruptively transform cement manufacturing, especially considering that the production-and-use of Portland cement is poised to grow to >6 Gt by 2030. This project reimagines cement production through end-to-end technological breakthroughs that features a solar energy-powered, two-stage process: a novel electrochemical decarbonation process to produce lime without attendant carbon dioxide release; and ultrafast production of cement via a novel high temperature synthesis procedure.

The two-stage process enables unprecedented manufacturing capabilities; with cost-, energy-, and carbon dioxide -efficiencies substantially better than those of contemporary manufacturing technologies. The project is supported by the Division of Materials Research (DMR) in the Directorate for Mathematical and Physical Sciences (MPS), and co-funded by the Division of Chemistry (CHE) in MPS, the Division of Civil, Mechanical and Manufacturing Innovation (CMMI) in the Directorate for Engineering (ENG), and the Division of Undergraduate Education in the Directorate for Education and Human Resources (EHR).

The overarching goal of this project is to enable the production of Portland cement, as well as other lime-based cements, in a carbon -neutral and energy-efficient manner. To achieve this goal, the project advances several technological innovations: (1) Low-temperature, carbon-neutral decomposition of limestone into lime; (2) Ultrafast production of cements, that are physically and chemically similar to their commercial counterparts, via a high temperature synthesis procedure; (3) Use of renewable energy, in lieu of fossil fuels, to power all sub-processes of cement manufacturing; and (4) Synergistic use of advanced experiments, thermodynamic and multiphysics simulations, and artificial intelligence to optimize the manufacturing process, that results in a family of sustainable, next-generation cements.

Outcomes of this work are expected to substantially advance understanding of process parameters that influence the kinetics, efficiency, and quality of the products from both stages of the manufacturing process. A simple, easy-to-use software, with hardwired thermodynamics and machine learning engines, will be developed to aid manufacturers in ascertaining optimal recipes based on their cement production targets.

The integrated education and workforce development plan emphasizes training of next generation of sustainable manufacturing researchers and engineers through conventional modalities, as well as novel means such as bootcamps, and workshop for advanced-skills training of skilled technical workers (STWs) and industry professionals.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.