Sustainable dimethyl ether synthesis pathway based on MSW gasification and carbon dioxide utilization

This study proposes a novel pathway for dimethyl ether (DME) production through municipal solid waste (MSW) gasification. By introducing additional carbon sources via MSW gasification and combining with CO2 hydrogenation reactions, efficient carbon resource utilization and synergistic emission reduction are achieved. The system design integrates the Kalina cycle for waste heat recovery and incorporates carbon capture units, where the captured CO2 can be utilized as partial synthesis feedstock, thereby enhancing overall carbon resource closure. Two process routes (direct synthesis and indirect synthesis) are proposed, with established and validated process models. Comparative analyses show the indirect pathway achieves 63.40 % energy and 61.40 % exergy efficiency, with a 9.04-year dynamic payback period and 2500.25 KUSD net value. The direct pathway outperforms at 76.77 % energy and 65.83 % exergy efficiency, a 5.99-year payback period, and 4811.20 KUSD net value. This research provides efficient and low-carbon solutions for sustainable fuel production and waste resource utilization.