Preliminary Evaluation of Pre-Reduction of Carbon-Based Titaniferous Magnetite Pellets for Reduction of Energy Requirements in the Vanadium and Steel Co-Production Process

Smelting of titaniferous magnetite (titanomagnetite) for the co-production of steel and vanadium is an energy intensive process. A laboratory and desktop (Pyrosim) study was conducted to investigate pre-reduction of carbon-based titanomagnetite pellets for reduction of energy requirements in the overall process. Energy requirements for smelting untreated and pre-reduced titanomagnetite pellets at temperatures ranging between 900°C and 1200°C were determined. Degrees of Fe metallisation (DOM) and reduction (DOR) at respective temperatures were similar, and increased with increase in prereduction temperature, from below 20% at 900°C, to about 91% at 1100°C, and about 98% at 1200°C. Simulation results showed that pre-reduction at 900°C, 1100°C and 1200°C resulted in respective overall process energy savings of 8.2%, 4.8% and 3.8%. DOM and DOR of carbon-based titanomagnetite pellets at 900°C were low, thus a higher prereduction temperature of 1100°C associated with higher energy savings and appreciable DOM and DOR would be recommended. High DOM and DOR result in higher process throughput, and reduction of the possibility of slag foaming during smelting.