Cost and Heat Integration Analysis for CO2 Removal Using Imidazolium-Based Ionic Liquid-ASPEN PLUS Modelling Study

Abstract

The recent advancement in efficient and recoverable CO2 capture solvents has been stimulated by the environmental harm resulting from the accumulation of greenhouse gases. Ionic liquids (ILs) and IL-based solvents have given rise to a novel method of CO2 collection that is highly efficient, economical, and environmentally benign. However, there is a lack of knowledge about the implementation of this process on a wider scale, and it has limitations, including high solvent costs. This simulated study shows that [EMIM][NTF2] can remove up to 99.4% of the CO2 from industrial waste effluents using three distinct compositions. Following an economic study using a 20-year plant life estimate, with a plant capacity of 4000 kg/h (206.165 kmol/h) for the raw mixed stream flow (inlet) and a maximum CO2 capacity of 38.1 kmol/h, it was determined that the process’s overall annualized cost was USD 2.1 million with operating expenses being USD 1.8 million. The Aspen Activated Energy Analysis’s recommendation of adding a heat exchanger, with a payback year of 0.0586 years, a 23.34 m2 area, and potential energy cost savings of USD 340,182/Year was also implemented successfully. These findings propose a conceptual framework for the development of novel ionic liquids for CO2 capture. It also demonstrates that sustainable [EMIM][Tf2N]-based absorption techniques for CO2 capture have the potential to be an industrial technology.