Direct Olivine Carbonation: Optimal Process Design for a Low-Emission and Cost-Efficient Cement Production

Employing mineral carbonation products as a cementitious substitute could reduce the cement industry's greenhouse gas (GHG) emissions. However, a transition toward low-emission cement requires financially competitive cement production at standardized product specifications. Aiming to tackle this challenge, we modeled and optimized a direct mineral carbonation process. In detail, we embedded a mechanistic tubular reactor model in a mineral carbonation process and imposed product specifications based on the European cement standard in the optimal design formulation. In the next step, we considered the business case of blended cement consisting of ordinary Portland cement and the mineral carbonation product that could be categorized as CEM II in the European cement standard. We computed the minimum production cost and GHG emissions of the produced blended cement by using Bayesian optimization to find Pareto optimal operating conditions of the mineral carbonation process. Our results showed that the cost of mineral carbonation in the cement industry can be competitive while cutting the GHG emissions by up to 54%.