Investigations of CO2 mineralization processes from mafic, ultramafic rocks, along with industrial alkaline waste within the framework of CCUS

Séminaire de Pascale Bénézeth (GET).

Abstract

Reaching net zero emissions by 2050 would require a decrease of ~1.4 GtCO2 per year. This involves holistic solutions and a multifaceted engineering strategy that includes substantial amounts of both Carbon Capture and Sequestration (CCS) and other Carbon Dioxide Removal (CDR) methods. Permanent mineralization of carbon in mafic and ultramafic geologic formations is one of a promising strategy for reducing anthropogenic CO2, as demonstrated by two pioneering field projects (Carbfix and Wallula) and natural occurrences. However, conditions and elementary processes that control the sequestration potential of mafic and ultramafic rocks depend on many factors (mineralogy, temperature, pH, pCO2, fluid chemical composition) as well as thermodynamic, kinetic, hydrodynamic and mechanical constraints, which have been addressed by numerous experimental and numerical efforts and have been the focus of much of our research for over a decade.
Moreover, in the context of the decarbonization of industry, innovative solutions and technological breakthroughs are also needed to reduce the CO2 emissions, especially in challenging sectors like cement manufacturing, which contributes to ~8% of global CO2 emissions and is hard-to-abate. Therefore, research is ongoing to find alternatives to traditional Portland cement.
Carbon mineralization, including biomineralization, will be illustrated at various scales and contexts, whether geological or industrial.