CS237844B1 - The method of iron removal from ssgregačnshe magnesite sleeper - Google Patents

Abstract

The invention belongs to the field of processing. It solves a method of removing iron from segregated magnesite roast by wet method. The procedure is that the magnesite raw material after segregated roasting with a grain size of 0.1 to 0.3 mm is wet magnetically separated at a magnetic induction of 0.01 to 0.3 T into magnetic and non-magnetic fractions. The non-magnetic fraction is repeatedly purified.

Description

The invention relates to a method of removing iron from a segregating magnesite fret by wet magnetic separation.

A significant part of the magnesite raw material drawn in our territory contains 2 to 7% by weight of iron, bound in the structural grid of magnesite. Magnesium with higher Fe content can be evaluated after treatment by segregation roasting to low-iron bricks. Proceed in accordance with MS. No. 169 480 and No. 214 356, when the starting magnesite raw material is roasted with the addition of magnesium chloride and a solid carbon reducer without air at a temperature of 800 to 1100 ° C. For such technologically modified raw materials the methods of iron removal have not been solved, their need appears due to the developed methods described in the cited author's certificates. The use of a dry or wet separation method depends on the requirements of the subsequent technological process. If the process requires the treatment of dry material, it is advantageous to use dry magnetic separation with heating according to CS. aut. osv. 237 831. If the subsequent technological process requires a wet separation method, then it is possible to carry out the separation of segregated roasted magnesite either by flotation according to Czechoslovakian patent no. autorského osv. No. 250 783 or wet magnetic separation. The first method, protected in MS. Certificate No. 237 831 is a method of ironing a segregating magnesite fret in a dry way, when the magnesite fret containing coke grains is preheated and at 170 ° C + 10 ° C dry separates to a magnetic induction of from 0.01 to 0.3 T and a non-magnetic fraction which is purified in the process repeatedly under said conditions.

The second method according to MS. Certificate No. 250 783 is a method of removing iron from a magnesite fret by a flotation method wherein after agitation with the respective flotation reagents, the mash is separated in the flotation cell to obtain a higher iron content product and a low Fe content whole product.

A disadvantage of the flotation process of separating segregated roasted magnesite is that if the metallic Fe is accidentally closed in the magnesite grain, such a grain cannot be flotated into the foam product, since flotation is a surface process at the interface of a solid, liquid and gas.

This drawback removes the method of removing iron from magnesite fret by wet magnetic separation according to the invention, characterized in that the magnesite raw material with an iron content of 2 to 7% by weight and a grain size of 0 to 0.3 mm is magnetically separated into wet by magnetic induction 0 01 to 0.3 T per magnetic and non-magnetic fraction. Preferably, the non-magnetic fraction is purified repeatedly.

The advantage of this process is that in the wet environment, the adhesion of the individual beads, which form clumps during dry magnetic separation at a certain moisture content, is eliminated.

The common advantage of wet magnetic separation of segregating magnesite flotation with flotation separation is that in the aquatic environment it is dechlorinated and the calcium is removed from the magnesite raw material in which it was present in the form of CaCO3 and CaMg (CO3) 2 during metallurgical processes. calcium chloride, water soluble and leachable. The calcium content in the flotation application is up to 3% by weight. and after leaching in the wet magnetic separation process, its content in the segregating magnesite fret is reduced to 0.2% by weight, or the sample contains no calcium.

Separation can be realized by subtasks No. 1.

Scheme No. 1

Praženec v

0,12 T

Me

0,12 T

By introducing multi-stage wet magnetic separation - control and purification (see Scheme No. 2) it is possible to obtain an iron-separated segregation magnesite fret with an iron content below 1% by weight.

Scheme 2

Praženec

Basic magnetic separation

Me

Ni

Clean separation of magnetic parts

Non-magnetic fraction control

M, 2M. M ₂ n

Claims (2)

Wet magnetic separation of segregated magnesite roast Examples 1 to 6 — Table No. 1 Attempt No. Products of disaggregation Mass yield γ (% by mass) Fe content /Fe (% wt.) e (% wt.) calculated « (% wt.) I. Me 12.24 22.08 270,259 77.03 May 2.04 6.24 12,729 3.64 N 85.72 0.79 67,718 19.33 L 100.00 350,707 100.00 3.51 II. Me 12.35 25.40 313.69 77.65 I have 1.23 8.10 9.96 2.46 N 86.42 0.93 80.37 19.89 L 100.00 403.82 100.00 4.04 III. Me 12.24 30.64 375.03 79.00 I have 4.08 6.80 27.75 5.84 N 83.68 0.86 71.96 15.16 L 100.00 474.74 100.00 4.75 IV. Me 11.52 26.33 303.32 79.37 M2 1.30 6.03 7.84 2.05 N 87.18 0.92 71.00 18.58 L 100.00 382.16 100.00 3.82 V. Me 13.10 21.09 276.28 77.27 I have 4.26 2.98 12.69 3.55 N 82.64 0.83 68.59 19.18 2J 100.00 357.56 100.00 3,575 VI. Me 6.52 26.33 171.67 51.40 I have 13.04 6.03 78.63 23.55 N 80.44 1.04 83.66 25.05 L 100.00 333.96 100.00 3.34 M = magnetic component N = non-magnetic fraction γ = product mass yield in % y _c = magnetic fraction (% by mass) y _t = non-magnetic fraction (% by mass) ε = yield of Fe into individual fractions (% by mass) — .100% (%) 100 . and β ~ metal content in the magnetic portion and = metal content in the input to the separation process — in the input sample & — metal content in the non-magnetic portion The balance check of individual products is carried out according to the relationship: 100 . a · = y _c . β + y _t . & The Fe content in feed a has a different value, as various amounts of additives (coke, CaCl, etc.) are added to the magnesite raw material in the process of segregation roasting, which changes the percentage of iron by weight in the sample, which represents the feed for segregation. Note: Part of the magnetic disintegration of the samples was carried out on a wet trough magnetic disintegrator — another part on a laboratory wet magnetic disintegrator. SUBJECT 1. A method of removing iron from a segregation magnesite roaster by wet magnetic separation, characterized by the fact that magnesite raw material with an iron content of 2 to 7% by weight with a grain size of 0 to 0.3 mm is magnetically separated according to the invention wet with magnetic induction from 0.01 to 0 3 T into magnetic and non-magnetic parts. 2. The method according to point 1, characterized in that the non-magnetic portion is repeatedly purified.