Abstract
Hydrogen direct reduced (H2DRI) production and subsequent melting in an electric smelting furnace (ESF) is a promising low-emission ironmaking pathway for low- to mid-grade ores. This study applies a laboratory-scale shaft furnace H2DRI + ESF process to New Zealand’s titanomagnetite (TTM) ironsand. TTM ironsand was first pelletised to produce a suitable shaft furnace feedstock. A laboratory-scale shaft furnace was then commissioned, reducing a moving pellet bed by up to 96% reduction degree under counter-current H2 flow. Subsequent DC-arc smelting trials were conducted on the carbon-free H₂DRI pellets blended with unreduced ironsand, carburiser, and fluxes. The influence of carbon charge and reduction degree of H2DRI was examined, with key focus on carburisation and vanadium partitioning behaviours. ‘Green’ pig iron ingots were produced and separated from high-titania slags, with up to 92% vanadium recovered in the metal phase. Collectively, the findings show the potential of an H2DRI + ESF process for future industrial-scale ironmaking from TTM ironsand ores.