Low-carbon transformation of ethylene production system through deployment of carbon capture, utilization, storage and renewable energy technologies

Ethylene industry contributes significantly to the world economy, but the conventional steam cracking based production process generates huge amount of CO2 emissions due to massive use of fossil fuels for power and heat supply. Deploying technologies of carbon capture, utilization and storage (CCUS) and renewable energy is urgently necessary to steer the emission-intensive ethylene industry towards carbon neutrality. To attain this goal, this paper proposes a low-carbon ethylene production system with the joint deployment of CCUS, wind turbine, solar heat collector, electric boiler and thermal energy storage technologies. Energy, economic and CO2 generation/reduction performance models of each equipment are developed first. Based on which, a mixed-integer liner programming framework is constructed to find the optimal capacity configuration and coordinated operation scheme of the multiple devices, laying a foundation for the reliable, economical and low-carbon operation of the integrated system. Case studies on a practical ethylene production system demonstrate that the proposed low-carbon retrofit leads to 57.50% CO2 reduction at the expense of 15.92% total annual cost increase. Discussions are then carried out to investigate the effects of different decarbonization routes, the impact of carbon emission trading price, the approach to promote the deployment of CO2 hydrogenation to methanol, and the advantage of taking carbon capture as flexible load, through which, broader insights are provided for the lowcarbon transformation of the ethylene industry.