Design and analysis of a CO2-to-olefins process, using renewable energy

Abstract

This paper presents a light olefins production plant that hydrogenates carbon dioxide to C₂-C₄ using green hydrogen and electricity produced from solar and wind energy resources. In this regard, combining Fischer-Tropsch and methanol-mediated pathways on a large scale is analyzed as a new method to increase light olefins production. Additionally, an optimized hybrid renewable energy system comprised of solar panels, wind turbines, electrolyzers, batteries, converters, and so on is designed to supply the necessary utilities for the plant. The simulation results indicate that 590.9, 744.8, and 522.9 kg/h of ethylene, propylene, and butylene can be produced by processing 10% of carbon dioxide emitted from a cement factory, resulting in the negative emission of 2.14 kg CO₂/kg C₂-C₄. This plant needs 1420 kg/h of hydrogen to convert carbon dioxide into light olefins and 32 MW of electricity to meet hot, cold, and electric utility requirements, all powered by renewable energy. The optimization results demonstrate that the initial capital and net present costs of the renewable energy system are $1.15B and $1.38B, respectively, leading to the levelized costs of hydrogen and electricity of 3.56 $/kg and 0.12 $/kWh, respectively.