A new pathway to integrate novel coal-to-methanol system with solid oxide fuel cell and electrolysis cell

Abstract

Considering the significant emissions associated with conventional coal-to-methanol (CTM) systems and the increasing demand for renewable energy consumption, this study proposes a novel scheme for CTM, which couples a solid oxide fuel cell (SOFC) and solid oxide electrolysis cell (SOEC). The objective is to reduce coal consumption and carbon emissions. The proposed scheme involves introducing green hydrogen, enriching CO2 concentration, and recovering it from exhaust gas. A system simulation model was developed using Aspen Plus/Aspen Custom Modeler software for the design and sensitivity analysis. The design results demonstrate that by utilizing green hydrogen produced through H2O electrolysis in the methanol synthesis process, the coal consumption per unit of methanol production can be reduced from 1.26 kg/kg to 0.74 kg/kg. Moreover, by employing SOFC instead of conventional heat boiler system, the CO2 concentration in CTM exhaust can be significantly improved from 9.11 % to 30 %, enhancing the efficiency of carbon separation. The inclusion of a CO2 electrolysis process helps converting CO2 into a part of methanol capacity and achieving zero-carbon emissions. The findings aim to provide a reference basis and theoretical guidance for the design, optimization, and integration of renewable energy sources into the novel coal-to-methanol system with solid oxide cells.