Techno-economic and climate impact analysis of carbon utilization process for methanol production from blast furnace gas over Cu/ZnO/Al_2O_3 catalyst

摘要

This paper presents conceptual design, economic evaluation, and sensitivity analysis of a commercial scale carbon-utilization process that produces methanol (MeOH) from blast furnace gas (BFG). Three process cases that use different N_2 compositions in the feed (Case 1: 40%, Case 2: 35%, and Case 3: 30%) are simulated. The kinetic model over a commercial Cu/ZnO/Al_2O_3 catalyst is used to consider the effect of N_2 on the reaction and to find the optimal process synthesis condition. The proposed process yields 78.3-113.3 kt_(MeOH)/y with 32.2-40.2% energy efficiency, and after heat integration it has no requirement for external heat. Case 3 improves energy efficiency by 5.2% compared to the conventional electricity production process from BFG. The process is assessed using techno-economic and environmental metrics. The lowest minimum selling price of US$ 902/t_(MeOH) and the highest potential to reduce CO_2 emissions of 3.9 t_(CO2)/t_(MeOH) are obtained for Case 3. Sensitivity analysis for H_2, electricity price and major economic assumptions shows that Case 3 is the better option in the ranges of H_2 price, except high-priced H_2 produced by solar energy, and in ranges of electricity price using current technology. Case 3 is a techno-economically viable alternative under positive assumptions.