Coupled thermo-hydro-chemical modeling of accelerated carbonation of cement-based materials: Application to CO2 uptake
Farah Kaddah, Ouali Amiri, Philippe Turcry, Harifidy Ranaivomanana, Emmanuel Rozière
Abstract
The use of CO2-rich hot gases from cement plants or combustion processes is considered as an attractive method to accelerate the carbonation of recycled concrete aggregates (RCA). However, there is limited knowledge regarding the kinetics and mechanisms of accelerated carbonation induced by wet gas with a temperature of approximately 80°C. Water transport and temperature influence several parameters of the carbonation of cement-based materials, thus understanding and predicting their overall effect remains complex. The present study combines experimental and numerical investigations into the effects of temperature on carbonation processes. The experimental study focuses on understanding the effects of temperature on the evolution of the carbonation front, changes in chemical composition, and moisture transport within a cement-based material during carbonation in controlled conditions. The experimental data obtained serve as calibration parameters for a thermo-hydro-chemical coupled model of carbonation. The carbonation model incorporates heat transfer between the cement-based material and the external environment, considering the influence of temperature on water transfer, as well as the dissolution and carbonation of hydration products.