Energetic-Environmental-Economic Assessment of Integrated Different Carbon Capture and Compression Processes for High CO₂ Concentration Gas

Ionic liquids (ILs) have received growing consideration as a prospective decarbonization solvent. Nevertheless, most studies have focused on flue gases with specific compositions and flow rates, which makes it a challenging task to use ILs with divergent CO2 emission scenarios for the comprehensive carbon management. In this work, complete conceptual designs for absorption processes 1-butyl-3-methylimidazolium acetate ([bmim][Ac]) are developed for separating at least 90% of CO2 from the feed before pressurizing it to 150 bar to the sequestration sites over a broad range of CO2 flue gas compositions and flow rates. Each scenario is rigorously modeled, simulated, optimized, heat integrated, and compared with the conventional process by MEA. The simulation results show that compared to conventional processes, IL-based processes are only quite economical at high flue gas flow rates and CO2 contents. Also, a quantitative method toward technology comparison and scaling up is presented, which helps in selecting the suitable technology when input conditions change. Finally, a cost model for investment and operating costs of various emission sources is proposed as a tool to design an energy-saving and cost-efficient CO2 supply chain network for the future.