Studies on characterization of properties of low-grade hematite iron ores and their fired pellets.

This article focuses on the effects of iron ore type, binder type, and firing conditions on the properties of pellets made from low-grade hematite iron ores sourced from Ramallakota and Veldurthi mines in Andhra Pradesh, India. Pellets were prepared using bentonite and molasses binders in varying proportions and fired at temperatures between 1173 K and 1573 K for different durations. Results showed that increasing binder content reduced moisture in green pellets and improved mechanical strength, with bentonite generally producing stronger fired pellets than molasses. Higher firing temperatures and longer firing times enhanced pellet crushing strength and decreased apparent porosity due to increased sintering and slag bonding, with Ramallakota pellets exhibiting higher strength and porosity than Veldurthi pellets. X-ray diffraction confirmed hematite as the major phase in all samples, and scanning electron microscopy revealed intensified particle sintering at higher firing temperatures.