RU2191634C1 - Method of producing high-quality concentrate from magnetite quartzites - Google Patents

Abstract

FIELD: wet magnetic concentration of minerals, mainly, finely disseminated iron ores processed at integrated mining and concentration plants. SUBSTANCE: method includes wet grinding of crushed ore, classification of ground product in hydrocyclones, magnetic hydroseparation (desliming) of hydrocyclone overflows, magnetic separation of hydroseparator sands. Hydrocyclone overflow and sands of magnetic hydroseparation (desliming) are subjected to magnetic activation including passing of suspension through holes of ferromagnets whose internal walls are constantly maintained in magnetized state by action of on-coming magnetic fields on said ferromagnets. EFFECT: low-cost production of low-silicon high-grade concentrate. 1 dwg

Description

 The invention relates to the field of wet magnetic mineral processing, mainly finely disseminated strongly magnetic iron ores (magnetite quartzites).

 There are various methods of wet magnetic beneficiation, including grinding crushed ore, classification of crushed product in hydrocyclones, magnetic hydroseparation (or deslamation) of draining hydrocyclones, and magnetic separation of sands of magnetic hydroseparators (deslaminators), where the final magnetic separation concentrate is obtained (see the Guide to ore beneficiation: Special and auxiliary processes / Under the editorship of OS Bogdanov - M.: Nedra, 1983, as well as Pat. 1704830 RU, decl. 09.11.89, registered 04.04.95, pat. 2147467 RU, decl. 23.12.98 , registered. 04/20/2000).

 A disadvantage of the known methods of wet magnetic concentration of magnetite ores is the high content of quartz in the final concentrate of magnetic separation (usually more than 6%) due to the large capture of relatively large particles of quartz and poor intergrowths of magnetite and quartz into the magnetic product of the separators. Therefore, at present, in all foreign factories, such a concentrate is additionally enriched mainly by flotation with regrinding and additional enrichment of the poor industrial product allocated at the same time.

 There is also known a method in which to obtain a high-quality concentrate from magnetite quartzite, which is necessary for non-domestic steel production, the concentrate is enriched in a separate factory. In this case, the final concentrate of magnetic separation is crushed and subjected to repeated magnetic enrichment (for the prototype see "Mountain Journal", 1996, 3, pp. 27-32).

 The disadvantage of all known methods for producing high-quality concentrate from magnetite quartzites, including the prototype, are the high costs associated with the enrichment of the final magnetic separation concentrate (the so-called rough magnetic separation concentrate).

 The aim of the invention is to develop a method for producing high-quality concentrate from magnetite quartzite on the existing equipment of the sections of the processing plant, producing the final magnetic separation concentrate.

 This goal is achieved by the fact that the discharge of hydrocyclones and sands of magnetic hydroseparators (deslamers) is subjected to magnetic activation, including the transmission of a suspension (iron ore pulp) through holes in ferromagnets, the inner walls of which are constantly maintained in a magnetized state due to the action of counter magnetic fields on these ferromagnets. Such magnetic fields are created by orientation of permanent magnets with the same magnetic poles towards each other.

 At the same time, very inhomogeneous magnetic fields are created in the channels for the suspension to pass through the ferromagnet located in the opposite fields, which transfer the liquid phase of the suspension to the paramagnetic state at a certain concentration of iron ions in it. On magnetic separators and magnetic systems of hydroseparators, this leads, according to expression (1), to the displacement of quartz particles and poor aggregates into waste, which ensures the achievement of the goal.

где

- магнитная сила сепаратора, действующая на частицу кварца;

,

- размер (диаметр) и плотность частицы кварца соответственно;

- диамагнитная восприимчивость частицы кварца,

χ_жидк - диамагнитная восприимчивость воды, χ_жидк ≈ (-12•10^-6);
На чертеже приведен пример конкретного выполнения разработанного способа получения высококачественного концентрата из магнетитовых кварцитов.

Where

- the magnetic force of the separator acting on the quartz particle;

,

- size (diameter) and density of the quartz particle, respectively;

- diamagnetic susceptibility of a quartz particle,

χ _fluid - diamagnetic susceptibility of water, χ _fluid ≈ (-12 • 10 ^-6 );
The drawing shows an example of a specific implementation of the developed method for producing high-quality concentrate from magnetite quartzites.

 According to the method of draining the hydrocyclones of the second grinding stage and feeding the magnetic separation of the final stage, they are passed through perforated surfaces made of a steel ferromagnetic sheet, the ends of which are placed between the poles of the magnets of the same name. Drain from these perforated surfaces is returned, respectively, to the power of the first and final stages of magnetic separation. These operations provide an increased concentration of iron ions in the separation power and reduce the capture, as indicated above, of non-magnetic particles into the magnetic separation product. These operations in the developed method are called, respectively, the magnetic activation of the discharge of hydrocyclones and the magnetic activation of the power of the final stage of magnetic separation.

 Industrial tests of the developed method showed that it provides high-quality concentrate without reducing the productivity of the head mills in the initial ore, without increasing metal waste losses and without increasing operating costs compared to conventional sections of the factory producing magnetic separation rough concentrate. Thus, the developed method ensures the achievement of the purpose of the invention with obtaining significant economic effect.

Claims (1)

 A method of obtaining a high-quality concentrate from magnetite quartzite, including wet grinding of crushed ore, classification of the crushed product in hydrocyclones, magnetic hydroseparation (deslamation) of hydrocyclone discharge, magnetic separation of hydroseparation sands, characterized in that hydrocyclone discharge and magnetic hydroseparation sands are subjected to magnetic activation (deslamation) including passing the suspension through holes in ferromagnets, the inner walls of which are constantly supported in magnetization state due to the effect of counter magnetic fields on these ferromagnets.

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