SU1421411A2 - Method of flotation of iron ores - Google Patents

Abstract

The invention relates to the enrichment of minerals and m. used in reverse anionic flotation of oxidized iron ores. In order to improve the quality of the concentrate and reduce the consumption of reagents by stabilizing the equilibrium composition of water, the amount of injected lime, equivalent to the concentration of carbonate ions, is determined taking into account the equilibrium concentration of calcium ions by the formula P. „COj. ES “R / Sa, where Sar is the amount of lime to be injected ... ... l. mg / l; CO — ion concentration, mg-eq / l; - equilibrium concentration of Ca ions is 0.25-0.7; 3cgQ is mg-equivalent of CaO, {Equal 28. The equilibrium concentration of Ca ions is determined based on the law of mass, the material balance of particles containing calcium, and a given pH of the solution according to the equations in the invention. Using the method to enrich the magnetic middis concentrate with an iron content of 64- 66.5%. The average iron content in the tails is 21%. The consumption of a technical lignosulfonate depressor does not exceed 0.45-0.52 kg / t, its residual concentration in water is 70 mg / l. i (Л С

Description

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The invention relates to the field of mineral processing and can be used for reverse anionic flotation of oxidized iron ores and is an improvement of the device according to the author. St. No. 1233939.

The purpose of the invention is to improve the quality of the concentrate and reduce the consumption of reagents by stabilizing the equilibrium composition of water.

In a known flotation process, lime is introduced in an amount that ensures the neutralization of calcium ions in the form of Ca in an equilibrium state.

The equilibrium concentration of ions is determined on the basis of the law of mass action, the material balance of particles containing calcium and a given pH of the solution according to the following equations:

Saon he, Sa (OH) f „; (one)

 OH C fj K2 CaOH; (2)

 (OH) J Ca; (3)

He's sleeping, (4)

where f (j, f,, fi are the activity coefficients for particles with charges of 0.1.2, respectively, dol,

The equilibrium concentration of Ca ions depends on the pH of the solution and the presence of the salts CS02 SO and SG). When the pH is changed from 11 to 13.8, the ion concentration decreases from 0.8 to 0. At pH 11.6-12.2, characteristic of flotation, it is 0.55 - 0.23 dol.al., without salts, in the presence of salts 0, J-0., 35 dol.ed.

Example 1. The studies were carried out under laboratory conditions. All water is treated, caustic soda 400 mg / l is metered into water 1 l and the ionic composition is determined: 0.6, CO 5.3, mEq / l. Calculation of lime consumption are according to the formula

 SOZA SAO SAO

Lime is fed to the solution in the form of milk of lime. A decrease in the resulting calcium ion excess of 5–6 mEq / l is achieved by contacting the solution with air (or NajCO3) for 3–4 h until the ratio of Ca: CO ions in water is reached. 1: 1-1 s2, and then floated by a known method.

PRI mme R 2. Flotation is carried out in semi-industrial conditions with a closed

(five)

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Q

five

2o

25

3Q

Jq

40

45

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water circulation at the plant with a capacity of 100 kg / h. Part of the water is subjected to treatment taking into account the proportion of Ca (drain of the tailing thickener).

Before starting, tap water is treated with caustic soda (400 mg / l), it fills the distribution tank, 6 m and tail thickener, controls the ion concentration and dispenses the lime in the amount required to neutralize C0 ions with calcium ions in the form - (calculated according to to formula (5)}. In the distribution tank, water is treated with lime in advance so that equilibrium water enters the flotation during the start-up of the installation (Ca2 1.2-1.5 meq / l, OH 10, C0 | 1.8 -3.6 mEq / l), and in the tail lime is metered immediately before launch ohm (5.5, CO 1.8). As a circulating water, plums of concentrate and tail thickeners (or a settling tank) are used, which enter the distribution tank (conditioner), and from there to all points of the flotation process. the liquid phase of the concentrate and flotation tails The equilibrium composition of the water for flotation is achieved by the fact that lime is metered in the tailing thickener together with the froth product in an amount required to neutralize С0 ions | taking into account the proportion of Ca, and the subsequent dilution of the discharge of the tailing thickener by the discharge of the concentrated thickener, the consumption of lime in which does not exceed the amount required for the deposition of sludge. The quartz is activated by lime, which is dosed for flotation after the collector. This method of obtaining water for flotation reduces the volume of tanks for settling water and feeds the bulk of lime into the tailing thickener, which prevents the concentrate quality from deteriorating if lime is supplied

in a concentrated thickener.

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The application of the developed method for the enrichment of the magnetic industrial product. KGOKOR makes it possible to obtain a concentrate with an iron content of 64–66.5%, the average iron content in the tails is 21%. Without fractionation and the use of mixtures, the consumption of a technical lignosulfonate depressant does not exceed 0.45-0.52 kg / ton.

  142141 The residual concentration of LST in water is 70 mg / l. Filtration of the concentrate proceeds satisfactorily without intensification with reagents - polyacrylamide and lime.

Thus, the method allows to improve the quality of the concentrate, to reduce the consumption of reagents. In addition, it allows all the recycled water to be used in the flotation process and thus eliminates the problem of wastewater treatment. The process can be carried out under the conditions of a closed internal water circulation. When solving the problem of utilization of wastes (tailings), production can be waste-free.

Claims (1)

Invention Formula The method of flotation of iron ores by ed. St. 9 1233939, distinguished1 y and, in order to improve the quality of the concentrate and reduce the consumption of reagents by stabilizing the equilibrium composition of water, the amount of lime injected, equivalent to the concentration of carbonate ions, is determined taking into account the equilibrium concentration of calcium ions by the formula Cao COV es „o where R. „is the amount of izvesao injected, sti, mg / l;  - concentration of CO ions, mg-SQV / L; Ca is the equilibrium concentration of ions, equal to 0.25-0.7; coO mg equivalent of CaO, equal to 28.