Integrated Syngas Generation and Fluidized-Bed Hematite-to-Magnetite Reduction: A Literature-Grounded Aspen Plus Simulation Study

Selective conversion of hematite to magnetite can upgrade iron-bearing solids, improve magnetic separation, and provide an intermediate route between ore pretreatment and deeper direct reduction. This study develops an integrated simulation framework in which syngas is not treated as a final product, but as the functional link between steam methane reforming and hematite reduction in a fluidized bed. Methane steam reforming and the water-gas shift reaction were modelled in Aspen Plus using a tubular reformer, a suitable cubic equation of state, and kinetic expressions consistent with nickel-catalysed reforming. The syngas target was defined by the downstream reducer rather than by conventional hydrogen purification: a total reactive gas flow of approximately ۱۰ "kmol" ⁄"h" , an "H" _"۲" ⁄"CO" ratio close to ۳, a temperature above ۶۰۰ °C after cooling and mixing, and adequate pressure for fluidized-bed delivery. Sensitivity analysis showed that low-pressure, high-temperature reforming improved methane conversion and syngas yield, while excessive water-gas shift would move the gas away from the desired mixed-reductant composition. A fixed-heat-flux reformer case produced ۹.۹ "kmol" ⁄"h" syngas with "H" _"۲" ⁄"CO" = ۳.۰۷ and ۹۲% methane conversion, while equilibrium coke checking predicted negligible solid carbon under the selected steam-to-carbon regime. The reducer model, operated at ۴۵۰ °C and elevated pressure, converted ۸۴.۳% of the hematite feed and produced approximately ۱۹.۷ "kmol" ⁄"h" magnetite. The results indicate that the main value of the proposed configuration is the closed process logic between syngas specification, gas-solid reduction, and fluidization requirements, although pressure matching, inert dilution, and experimental validation remain essential before scale-up

کلیدواژه ها:

syngas ، steam methane reforming ، hematite reduction ، magnetite ، fluidized bed