Innovative Coal-to-Olefin Process Integrated with Sustainable Renewable Electricity and Green Hydrogen

Abstract

The conventional Coal-to-Olefins (CTO) process is plagued by high CO₂ emissions and significant water consumption. To address these issues, two routes are designed and modeled to compare with the conventional CTO route in terms of energy consumption, CO₂ emissions, water consumption, and economic performance: the Renewable Electricity coupled to CTO process (RE-CTO) route and the Renewable Electricity and Green Hydrogen coupled to conventional CTO route (RE-GH-CTO). Introducing renewable electricity into the CTO process enhances the energy efficiency, reduces grid loads, and decreases indirect CO₂ emissions. The integration of green hydrogen technology removes the air separation unit and water–gas shift unit, shortens the process, reduces energy consumption, and improves CO₂ utilization. The RE-GH-CTO route can motivate a multienergy integration and complementation, improve energy efficiency, and boost light olefins productivity. The results showed that the RE-GH-CTO route improved energy efficiency and carbon utilization efficiency by 14.51% and 40.80%, and reduced carbon dioxide emissions and water consumption by 76.71% and 32.68% compared with the conventional CTO process. In addition, the production cost of the RE-GH-CTO route is 8.30% lower than the conventional CTO route. This innovative route provides a promising approach for introducing green hydrogen for CO₂ utilization and the sustainable conversion of coal to chemicals.