System-level feasibility analysis of a novel chemical looping combustion integrated with electrochemical CO2 reduction†

Abstract

The increase in greenhouse gas emissions and the subsequent global warming effects necessitate effective carbon dioxide (CO₂) mitigation strategies such as CO₂ capture and CO₂ utilization. Chemical looping combustion (CLC) is a promising technology that offers a low-cost and effective CO₂ capture while also generating power. With an increase in attention towards utilization of captured CO₂, this paper presents a novel polygeneration process integrating CLC with electrochemical CO₂ conversion for simultaneous power generation and production of valuable chemicals. This integration leverages the inherent CO₂ capture capability of CLC, providing low-cost capture while enabling the valorization of captured CO₂ into ethylene. A detailed techno-economic feasibility of this approach has been analyzed based on experimental data to develop a grey-box model for electrolysis. The overall process has been simulated using Aspen Plus along with the conventional process that generates power using conventional coal fired boilers coupled with amine-based CO₂ capture followed by valorization of CO₂via a similar electro-reduction unit to that in the proposed process, thus presenting a relative analysis between the conventional CCUS and proposed CLC-based CCUS approaches. The performance indicators have been defined that exhibit a trade-off between the CO₂ valorization and power generation while yielding efficiencies of the proposed process 9.16% points higher than the conventional variant. Furthermore, the polygeneration process demonstrated a feasible CO₂ valorization up to 15% while compromising the power generation. The economic assessments indicate a 21.6% reduction in the total annualized investment relative to the conventional process.