Features of solid-phase reduction of components of manganese ores of different genesis

The results of solid-phase reduction of components of manganese ores of different genesis, differing in the content of oxides of manganese, iron and phosphorus, are presented. The samples used were natural manganese oxide-rich monomineral ore from Brazil, ferromanganese concentrate of the Zhayremsky GOK (Kazakhstan) with a high iron content and ferromanganese ore of the Selezenskoye deposit (Russia) with a relatively high iron and phosphorus content. The results of the study of the phase composition of the initial ores and the distribution of the main elements in ore materials are presented. The influence of temperature, duration of exposure and type of reducing agent on the process of solid-phase reduction of elements is investigated. The experiments were carried out in a Tamman laboratory furnace at a temperature of 900 °С and 1000 °С and held for 90, 180 and 300 minutes. The possibility of selective reduction of iron from complex manganese ores to a metallic state not only with solid carbon, but also with carbon monoxide has been established. At a temperature of 900 °С in a CO atmosphere, iron can be selectively reduced without reducing P and Mn. With an increase in temperature to 1000 °С and the duration of exposure in the CO atmosphere, phosphorus is restored together with iron. In the case of reduction with solid carbon under these conditions, iron, phosphorus and manganese pass into the metal part. An increase in the duration of exposure at a temperature of 1000 °С is accompanied by an increase in the concentration of manganese in the metal phase. In all experiments, with the appearance of a new metal phase, a new oxide phase is also released, consisting of oxides of metals that cannot be restored under experimental conditions (magnesium, aluminum, silicon and manganese).