Reduction in fossil fuel consumption by exploiting separation of refractory grade oolitic iron ores using black plum leaf litter via magnetization roasting & pelletization; a small step toward decarbonization & sustainability

Abstract

An increase in the annual energy utilization beyond 20% for the iron & steel industries promotes sustainable development through augmented clean technologies. Moreover, the consistent development of the country always depends on its infrastructure growth and improved per capita consumption of steel, which leads to an increase in greenhouse gas(GHG) emissions. Therefore, pondering possible alternative technologies for low-carbon steel production while undisturbing the country's rapid growth is the need of the hour worldwide. The present research work assesses the use of Black plum leaf litters (BPLLs; solid carbonaceous biomass) as an alternative biomass reductant integrating magnetization roasting and pelletization while upgrading the low-grade refractory oolitic iron ore (OIO). The magnetite concentrate generated from oolitic iron ore (41.73% Fe(T), 14.51% SiO2, 8.61% Al2O3, and 12.36% loss on ignition (LOI; contributed mainly from clay and goethite) at 900 ℃, 45 wt% of BPLLs, and 5 min. of residence time have 64.37% Fe(T) with 65.56% yield suitable for pellet feed application. Higher volatile matter (VM:68.09%) in the BPLLs and the internal porosity of the oolitic ore stimulate the magnetization process at a lower roasting temperature. Moreover, the innovative approach of employing BPLLs in producing metallurgical grade pellets (Cold crushing strength(CCS):216.6 kg/pellet, Porosity:27.81%, RDI-2:RDI]-2.8 = 4.48%) from the OIO has the potential benefits in sustainable development and decarbonization. In this regard, more advanced characterization techniques like; X-ray microCT (X-ray microtomography), X-ray diffraction (XRD), Field emission scanning electron microscope (FESEM), and wet-chemical analysis were applied to evaluate the suitability of less carbon-intensive magnetite concentrate and indurated pellet production.