high-intensity magnetic separation in beneficiation of limonite ore

Among the planet iron ore deposits, the limonite ores will be the third-most abundant supply of iron. The overwhelming portion of these ores is represented by low-grade varieties iron ore ball mill dry type design layoutwhich can not be used in iron and steel business with out preliminary beneficiation.

Low contrast properties of metallic and non-metallic minerals, fine dissemination in addition to their tendency to sliming represent basic difficulties within the improvement of technologies for beneficiation of those ores.

Successful application of high-intensity magnetic separation in beneficiation of hematite ores types a basis to get a wider utilization of this technological process for therapy of these difficult-to-treat ores as limonite.

This report is the results of investigations performed in the mekhanobrchermet institute to develop a technology for beneficiation with the kremikovsky (bulgaria) and kerch (ukraine) limonite ores by high-intensity magnetic separation.

Magnetic separation of limonite ores from the kremikovsky deposit

Two examples of limonite ores representing 60 per cent of iron ore from your deposit had been investigated. The ores are seen as a varying mineral composition, textural and structural peculiarities and complex mineral intergrowth.

The metallic minerals are represented by iron hydroxides, hematite, manganese oxides and hydroxides containing barium and lead, magnetite, plumbojarosite, clayey minerals, barite and quartz. Mineral composition from the ore is shown in table i, whilst the chemical composition is offered in table ii. Tables iii and iv summarize macroscopic description and morphological characteristics, respectively.

Magnetic separation of limonite iron ores

Laboratory tests had been performed using a laboratory magnetic separator with horizontal magnetic field, height with the separation zone of 220 mm and also the maximum magnetic flux density of 1.five t in the separation zone.

A three-rotor magnetic separator with horizontal rotor was used in pilot-plant tests. The height in the separation zone in every rotor was 220 mm. The maximum magnetic flux density inside the upper rotor was 0.four t whilst 1.4 t was offered in the other two rotors.

The non-magnetic fractions from the upper and middle rotor had been cleaned in middle reducing rotors, respectively. Every rotor has two independent energy supplies and, consequently, six operations can be performed simultaneously.

Magnetic separation of limonite ores from the kerch deposit

The current processing plant treats two kinds of the limonite ore: "brown" ore, i.e. Coarsely disseminated oolite ore and "tobacco" ore which is finely disseminated using a cement binding. The beneficiation approach used is jigging.

With 97:3 ratio of brown to tobacco ores (1970) within the mix, the concentrate created by this approach contained 45.8 per cent of fe at 75.1 percent recovery. With 50:50 ratio of brown to tobacco ores (1985) within the mix, the grade in the concentrate decreased as a result of 44.6 percent and also the recovery of iron dropped to 63.1 %.