In the quest to secure the long-term viability of geological carbon storage (GCS), researchers have turned their attention to the often-overlooked yet critical component of wellbore sealants. A recent study, published in the journal *Carbon Capture, Utilization, and Storage*, has shed light on the carbonation behavior of a one-part granite-based geopolymer, offering promising insights for the energy sector.
The study, led by Mayank Gupta from the Department of Materials, Mechanics, Management & Design at Delft University of Technology in the Netherlands, integrates a novel pore-scale simulation framework with experimental validation. This approach aims to address the chemical degradation of conventional materials when exposed to CO₂-rich conditions, a significant challenge in GCS.
Gupta and his team developed a new model called ReacSan, which simulates CO₂ transport and carbonation reactions within the evolving microstructure of the geopolymer under conditions relevant to GCS. The model incorporates several advanced techniques, including CO₂ dissolution using the Redlich–Kwong equation of state, gel dissolution via transition state theory, ion transport using the Lattice Boltzmann Method, and chemical reactions through thermodynamic modeling.
The model’s validity was confirmed through experiments where equivalent geopolymer samples were exposed to CO₂ under in-situ conditions. The results showed a rapid carbonation process, leading to a decrease in pore fluid pH and the precipitation of CaCO₃. These experimental observations aligned well with the numerical simulations, demonstrating the model’s ability to capture both temporal and spatial variations in the microstructure and carbonation mechanisms of alkali-activated materials (AAMs) exposed to supercritical CO₂.
“This study not only validates our model but also provides a powerful tool for predicting the long-term behavior of AAMs in GCS applications,” Gupta explained. “The ability to simulate carbonation progression over longer time- and length-scales is crucial for ensuring the integrity of geological carbon storage.”
The implications of this research are significant for the energy sector. As the world increasingly turns to carbon capture and storage technologies to mitigate climate change, the need for robust and reliable wellbore sealants becomes paramount. The ReacSan model offers a novel approach to understanding and predicting the behavior of these materials, potentially paving the way for more efficient and effective GCS technologies.
Moreover, the study highlights the importance of interdisciplinary research, combining experimental and numerical methods to tackle complex scientific challenges. By bridging the gap between theory and practice, Gupta and his team have made a significant contribution to the field of carbon capture and storage, offering valuable insights that could shape future developments in the energy sector.
As the world continues to grapple with the challenges of climate change, research like this provides a beacon of hope, demonstrating the power of innovation and collaboration in the pursuit of a sustainable future.