Hydrogen-driven routes to steel from siderite with low CO2 emissions: A modeling study

Abstract

Efficient use of low-grade siderite minerals can not only potentially mitigate the shortage of iron ores but also enable drastic reduction in CO2 emissions from steel industry in China. In this study, we conducted a systematic thermodynamics analysis toward ferrous carbonate hydrogenation to CH4, which was verified by experimental study over the 5 wt.% Ni/siderite. CO2 hydrogenation reduction was introduced in steelmaking from siderite minerals to further reduce the CO2 emissions. Based on thermodynamic analysis results, we provided four options of hydrogen-driven route to steel from siderite named FTI-CO2HR, FTM-MTI-CO2HR, FTH-HTI-CO2HR and FTW-WTI-CO2HR, respectively. The FTM-MTI-CO2HR process route achieved minimized CO2 emissions (0.56 metric ton CO2/metric ton iron) and was competitive to the steel scrap-EAF route (0.54–0.60 metric CO2/metric ton iron). The proposed process route would be cleaner, more environment friendly assuming successful technology and process development and favorable market conditions in terms of acceptable level of hydrogen production cost.