Hardening Behaviour of Pellets Prepared from a Novel Combination of Rare Multimetallic Magnetite Ore and Binder

Abstract

Hardening behaviour of multimetallic magnetite ore (MMO) bonded with three different organic binders: corn starch, carboxymethyl cellulose (CMC), dextrin and one inorganic binder: colemanite, has been investigated. The study aimed to optimize the hardening parameter of MMO with a suitable binder. Four separate green mixtures with doses (0.5, 1, 1.5, 2) wt% were made for each binder. The pellets were fired at four different temperatures (1273 K, 1373 K, 1473 K, 1523 K) for 2 h, and porosity was measured. HR-XRD and SEM techniques were used to analyse the hardened pellets. Pellets bonded with organic binders showed sufficient green strength and dry strength, but failed at higher temperature except for CMC bonded pellets which gave better cold crushing strength (140 kg/pellet) compared to dextrin (21.6 kg/pellet) or corn starch (24.3 kg/pellet) bonded ones. Pellets bonded with 1.5 wt% colemanite gave optimum properties of cold crushing strength (294 kg/pellet) and porosity (25 volume%). © 2021, The Indian Institute of Metals - IIM.