Manganese ore is divided into manganese carbonate ore and manganese oxide ore. For different manganese ores, the beneficiation process is also different. Fodamon engineer analyze how to beneficiate according to different mineral properties as follows:
a. Beneficiation method and process flow of manganese carbonate ore
The main minerals in manganese carbonate ore are siderite, calcium siderite, manganese calcite and siderite; Gangue minerals include silicate and carbonate minerals, which are often accompanied by impurities such as sulfur and iron. The ore composition is relatively complex, and the embedded particle size of manganese minerals is fine to several microns, which is not easy to dissociate, and it is difficult to obtain a higher concentrate grade.
The beneficiation methods of manganese carbonate ore mostly adopt strong magnetic separation, heavy medium beneficiation and flotation. Sedimentary manganese sulfate ores generally adopt the sequential preferential flotation process of carbonaceous shale, pyrite and manganese minerals. Hydrothermal lead-zinc bearing carbon manganese ores generally adopt flotation strong magnetic separation process. In some sulfur-containing and manganese rich ores, manganese minerals are mainly sulfur manganese ores, which are generally removed by roasting. Some manganese carbonate rich ores are also roasted to remove volatile components to obtain finished ores.
Manganese carbonate ore contains some refractory ores. Manganese is closely associated with iron, phosphorus or gangue, and the embedded particle size is very fine, which is difficult to separate. Smelting methods can be considered. For example, manganese rich slag method for treating high phosphorus and high iron manganese ore, nitric acid leaching method for producing active manganese dioxide and electrolytic method for producing metallic manganese have been used in industrial production. In addition, there are calcium bisulfite method and bacterial leaching method.
b. Beneficiation method and process flow of manganese oxide ore
Manganese minerals in manganese oxide ores are mainly hard manganese, pyrolusite and hydromanganese, while gangue minerals are mainly silicate minerals and carbonate minerals, often accompanied by pig iron, phosphorus, nickel, cobalt and other components. The beneficiation method of manganese oxide ore is mainly gravity separation. Weathered manganese oxide ores often contain a large amount of slime and fine ore, and ore washing gravity separation method is used in production. The net ore obtained by washing the raw ore to remove the slime can be used as finished ore, and some need to be re selected with jigging and shaking table. Sometimes, ore washing overflow also needs to be further recovered by gravity separation or strong magnetic separation. Some sedimentary primary manganese oxide ores, due to mining dilution, adopt heavy medium and jigging to remove gangue in production to obtain massive concentrate.
Among iron bearing manganese oxide ores, iron minerals are mainly limonite. Iron and manganese are difficult to be separated by gravity separation, flotation or strong magnetic separation, so reduction roasting magnetic separation method is needed. The process of ore washing, reduction roasting, magnetic separation gravity separation has been adopted in industry.