Development of Effective Hydrogen Production and Process Electrification Systems to Reduce the Environmental Impacts of the Methanol Production Process
Abstract
The methanol industry, responsible for around 10% of GHG emissions in the chemical sector, faces growing challenges due to its environmental impacts. This article aims to reduce the lifecycle environmental impacts of the CO2-to-methanol process by exploring advanced electrification methods for hydrogen production and CO2 conversion. The process analysis and comprehensive life cycle assessment (LCA) are conducted on four different methanol production pathways: conventional natural gas, CO2 hydrogenation, trireforming of methane (TRM), and the novel electrified combined reforming (ECRM), by including two hydrogen production routes: PEM electrolysis and the innovative plasma-assisted methane pyrolysis. The LCA was performed using the ReCiPe method, covering midpoint and endpoint categories across four Canadian provinces—British Columbia, Alberta, Ontario, and Quebec. The efficient plasma technology improves environmental performance for all pathways. The plasma-assisted CO2 hydrogenation pathway in British Columbia and Quebec shows the lowest GHG emissions, achieving -2.01 and -1.72 kg CO2/kg MeOH, respectively. In Alberta, the conventional pathway has the lowest impact, followed by plasmaassisted TRM. The CO2 hydrogenation with the PEM pathway shows the highest GHG emissions at 8.00 kg CO2/kg MeOH, highlighting the challenges of using hydrogen from PEM electrolysis in regions with carbon-intensive electricity grids. However, the inclusion of carbon black as a byproduct further reduces the environmental impact, making these plasma-assisted pathways more viable. This LCA study underscores the influence of regional factors and technology choices on the sustainability of methanol production, with an example of a 107% reduction in GHG emissions when plasma-assisted ECRM is shifting from Alberta to Quebec.