Techno-economic assessment and feature importance analysis of gas hydrate-based carbon capture processes

Abstract

Among emerging CO2 capture approaches, hydrate-based carbon capture (HBCC) has shown particular promise for pre-combustion applications, given its eco-friendly, water-based solvent. This study conducted a comprehensive techno-economic assessment of various HBCC configurations and introduced a novel process design that transports CO2 as a hydrate. Compared to a state-of-the-art absorption process, the proposed HBCC design reduced the levelized cost of CO2 captured (LCOC) by 6.8%. Sensitivity analyses covering plant capacity confirmed that this configuration was especially cost-effective at lower feed flowrates. Further feature-importance analysis using SHapley Additive exPlanations (SHAP) revealed that removing the dissociation stage and decreasing the water-to-gas ratio were critical for minimizing LCOC. These results indicate that an optimized HBCC outperforms conventional methods in cost and efficiency while offering a straightforward path to improved economic and environmental viability.