Fine hydraulic screening for staged separation of titanium-magnetite concentrate

Abstract

This article covers the applications of fine hydraulic screening for the staged separation of titanium-magnetite concentrates upstream of the last grinding stage and provides an evaluation of its process efficiency options for the Kachkanarsky GOK. In all screen operating modes tested, the mass fraction of iron in the undersize was higher than its mass fraction in the oversize, but failed to reach the target value for the concentrate of 61 %. Therefore, the undersize must be subjected to additional magnetic concentration. Staged separation of the concentrate by fine screening allows either to improve concentrator performance (by up to 10 %) or to increase the concentration process indicators without changing the grinding equipment volume. In this case, the undersize yield averages 55 %. The use of the staged concentrate separation technology with fine screening at constant process parameters and steady factory performance allows reducing the tertiary mill volume in relative terms, not exceeding half of the undersize yield from the operation, which shall be 65–70 %. The minimum permissible values of the mass fraction of iron and of the –0.071 mm class in the screen feed and the undersize must be ensured for obtaining the required concentrate grade. The values of these indicators depend on the material composition of the ore and the concentration process used.

Iron ore beneficiation technologies in Russia and ways to improve their efficiency

“…2. The following can be used as beneficiation methods and devices for the staged concentrate separation: drum magnetic-gravity separators with a modified bath [23]; drum separators with an alternating magnetic field [24, 25]; MGS magnetic-gravity separators of a cylindrical type with a vertical direction of movement of the separated products [26]; fine screening [27]; gravity separation (screw separation) [5].…”

“…Therefore, the most promising for industrial application are practices with staged concentrate separation using a combined circuit with fine screening and magnetic separation of the undersize product (Table 5). The results of industrial tests of the staged concentrate separation using fine screening at the Kachkanarsky GOK showed that this technology makes it possible to reduce the volume of mills at the third stage by 25-33 % or increase the productivity of the beneficiation plant by 10 % [27]. With the same productivity of the plant and the volume of the mills at the third stage, the use of staged extraction of concentrate makes it possible to increase the extraction of iron into concentrate by 0.5-1 %.…”

“…Increasing the yield of magnetite concentrate and the extraction of iron into concentrate is mainly achieved by using technologies with staged extraction of concentrate [27] or by using drum separators with systems of permanent magnets with increased energy (Nd-Fe-B) at the first stages of beneficiation (DMS and WMS-I) [36,37]. The use of separators with increased magnetic induction (0.25-0.5 T) can lead to a decrease in the iron content in the concentrate.…”

Methodological substantiation of the choice for optimal modes of equipment operation during the stage-wise concentrate removal in iron ores beneficiation

“…The operating principle of MG separation is based on the control of magnetic aggregation when a ferromagnetic suspension is exposed to a low-strength magnetic field and a centrifugally ascending water flow. Fine screening is widely used at many mining and beneficiating enterprises for diverse types of mineral raw materials and makes it possible to achieve an increase in the productivity of beneficiating plants, improve the quality of products, and reduce operating costs [25][26][27][28][29][30][31].…”