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Abstract

Specular hematite is the most stable form of hematite, which resists reduction even at high temperatures in a reducing gaseous atmosphere. Therefore, the mechanical activated reduction of specular (micaceous) hematite concentrates has been investigated. The specular hematite particles were milled in a high-energy attritor mill with varying milling time to obtain lamellar-free particles and fine iron oxide. The oxide powder was converted into redundant metallic iron powder by heat treatment at various temperatures (700–1100°C) in a 40% H₂+Ar atmosphere. The influence of processing variables on powder characteristics has been evaluated. The reduced iron powders were characterised by using inductive couple plasma analysis, X-ray diffraction and scanning electron microscopy. In this manner, fine (15 μm in size) reduced iron powders with low carbon (0·01% C) and sulphur (0·05% S) content were successfully produced at low temperature (950°C).

Keywords

MECHANICAL ACTIVATION DIRECT REDUCTION SPECULAR IRON OXIDE SPONGE IRON POWDER

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Direct reduction of mechanically activated specular iron oxide

Abstract

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