Towards low-carbon consumption and cleaner methanol production via hybrid hydrogen supply strategy: A techno-economic-environment assessment

A techno-economic-environment assessment framework of methanol production from coal integrated with a hybrid hydrogen supply strategy is established, gathering an insightful perspective of its broad sustainability and providing an effectually hybrid green, blue, and gray hydrogen supply plan to evaluate its performance. Process simulation and life-cycle analysis indicate that coal to methanol integrated with reverse water gas shift using coal to hydrogen (CTM-RWGS-CTH) and CTM-RWGS with water electrolysis using wind energy process show relatively independent excellent technical and environmental performance, respectively. To comprehensively utilize hydrogen energy to realize process integration and intensification, "balance points" are proposed and defined. Moreover, eleven possible hybrid hydrogen supply modes are developed and analyzed. Results show that the quaternary H2 supply strategy exhibits enormous economic advantages, 0.051 $/kg methanol. The "balance point" in the quaternary H2 supply strategy is CTM-RWGS-CTH 13%, CTM-RWGS H2 from CTH without carbon capture, utilization and storage 37%, CTM-RWGS H2 from byproduct gas to hydrogen 16%, and CTM-RWGS H2 from water electrolysis using wind energy process 34%. Our hybrid hydrogen supply strategy embraces the full potential role of emerging CTM-RWGS processes to achieve low-carbon consumption and cleaner production, which should prevail over purely unitary hydrogen resources.