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

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.