ABSTRACT
This chapter deals with reagents that have been used in processing a variety of iron ores, especially low-grade types. The emphasis is on applications of various reagents for separation of impurities from iron ore minerals, plus their chemical functions and physical properties. Flocculants are widely used in iron ore processing for three principal purposes: flocculation of concentrates prior to thickening and final dewatering, thickening of tailings slurries to reclaim water for reuse in the ore treatment, and clarification of dilute waste slurry streams for reclamation of water as an effluent from the plant. Two general classes of flocculants are presently employed in the iron ore processing industry—inorganic chemicals such as lime or alum, and high-molecular-weight synthetic organic polymers. The three general types of flotation reagents are collectors, frothers, and modifiers. The flocculation processes in iron ore processing systems are complicated due to effects and interactions of a number of variables as well as the heterogeneity of the ores.
