Modeling & Optimization of CO2-Mixture Frost Growth as a Carbon Capture Process & Integration with Sequestration
This dissertation develops and validates an integrated carbon-management framework that couples surface-level cryogenic carbon capture with subsurface geological sequestration. The first part of the study advances understanding of CO2 frost growth and densification during cryogenic desublimation. A machine-learning framework, trained on an extensive literature-based data set, predicts initial frost thickness and density across a wide range of gas compositions. Thermodynamic properties and phase behavior are described and calculated using empirical correlations available in the literature and the Soave-Redlich-Kwong (SRK) equation of state, enabling accurate estimation of desublimation temperatures and supporting the development of predictive frost-growth models. A comparative cost analysis highlights the potential of cryogenic capture to achieve high CO2 purity with lower overall energy demand than conventional cryogenic capture approaches. Building on the captured solid CO2, the study introduces a novel dissolution step in which the solid CO2 is converted into a CO2-saturated brine for direct subsurface injection. Reactive-transport in-house model, performed by coupling PHREEQC geochemical modeling with flow and continuity equations, examines the behavior of the injected brine in deep saline aquifers. The model quantifies permeability changes driven by geochemical reactions and fines migration. By linking cryogenic CO2 capture to brine-phase sequestration, this work presents a unified pathway for large-scale carbon management. The integrated approach not only lowers the energy penalty of capture but also provides a secure and permanent storage option, offering a scalable and cost-effective solution to industrial CO2 mitigation.
CO2-saturated Brine Injection, Carbon Sequestration, Cryogenic Carbon Capture
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