Iron mineral tailings have the characteristics of low grade, fine particle size, fine particle size of iron-containing minerals, complex symbiotic relationship, and easy mudification, which makes the work of re-selection and recovery of iron mines tailings more difficult. In the case of increasingly scarce iron ore resources and increasing dependence on foreign countries, it is particularly important to strengthen the re-election of iron ore tailings.
Iron tailings re-processing process depends on the nature of the ore, magnetic separation and its combined beneficiation process can be used to re-select iron tailings. The common processes include single magnetic separation process, gravity separation-magnetic separation combined process, flotation-magnetic separation combined process technology and flotation-magnetic separation-gravity separation combined process.
Iron in some iron tailings occurs in magnetite and weakly magnetic hematite and limonite. The gangue minerals are mainly non-magnetic quartz, calcite, etc. The magnetic difference between the two determines that the iron in the tailings can be recovered by magnetic separation. Due to the characteristics of the iron tailings, if the magnetic separation is carried out directly, the recovery index is not ideal. Therefore, fine grinding before entering the magnetic separation can dissociate the iron-containing mineral monomers, thereby improving the magnetic separation effect. The magnetic separation process is simple and convenient and does not produce additional pollution, and has been widely used in the re-election of iron tailings.
Because the grade of iron in iron tailings is low, pre-enrichment operation can be used to improve the grade of iron, and a large amount of tailings can be discarded. Considering the production cost and technology, the tailings are not pre-grinded. Because the density of iron minerals is greater than that of gangue minerals, gravity separation can be used for pre-enrichment of iron minerals. The spiral chute in the gravity separation equipment has the characteristics of small footprint, no power, large processing capacity, and stable separation process. Therefore, the spiral chute is used for pre-enrichment, the pre-enriched coarse concentrate is finely ground, the strong magnetic minerals are recovered by weak magnetic separation, and the tailings of weak magnetic separation are recovered by strong magnetic separation.
The combined process of magnetic separation and flotation enriches iron minerals through magnetic separation, improves the grade of ore entering the flotation operation, and at the same time can achieve the effect of desliming and impurity removal, and optimize the flotation environment. Commonly used flotation methods for iron tailings include anion positive flotation, anion reverse flotation, and cationic reverse flotation.
The positive flotation method of anion collector is suitable for ores with simple composition of iron oxide minerals. Cationic reverse flotation is suitable for the flotation of iron-bearing ores with complex components. If the grade of the ore to be selected is higher, the iron tailings can be enriched before entering the flotation process, so as to achieve a better flotation index.
The combined process of gravity separation, magnetic separation and flotation is used to recover iron in iron tailings. Gravity separation is usually used as a means of pre-enrichment to improve the grade of ore entering the magnetic separation operation. At the same time, pre-enrichment can also play the role of desliming and improve the recovery rate of magnetic separation. As a supplementary method, flotation can capture the conjoined organisms that cannot be recovered in the magnetic separation stage, thereby improving the recovery rate of the entire operation process.
The above are several commonly used methods in the iron tailings re-election process. In the actual beneficiation operation, because the properties of iron ore are different, the beneficiation test should be carried out first when selecting the process, and it is more reasonable to customize a suitable iron ore beneficiation process for it through experimental analysis.
To find out more about our products and solutions, please fill out the form below and one of our experts will get back to you shortly.
CHAT
MESSAGE
