RU1776202C - Method for mechanical separation of metals from metallurgical furnace slag - Google Patents

Abstract

Usage: the separation of metal from slag from metallurgical furnaces. SUMMARY OF THE INVENTION: metal is removed from its slag by crushing and pre-sorting to remove a fraction of less than 7 mm, passing it into the hopper 4. The residue is milled in mills 5 to obtain granules less than 40 mm and sorted again to separate another fraction with a size less than 7 mm. Slag larger than 7 mm is sent to the separator at a density of 8 to separate the metal from its slag. From a small hopper, the metal is sent to mu 9 with a content of 90% free metal. From the purifications of this separator 8, a granular concentrate of less than 7 mm in size and 60% metal is obtained, which is again sent to the same hopper 4. From hopper 4 it passes to another separator 10 with a mesh size of less than 0.5 mm. and thus, a metal is obtained with a grain size of 0.5-0.7 mm with a purity of from 95 to 98% and with a grain size of less than 0.5 mm with a purity of 98%. 1 ill. sl c

Description

PL PI

The invention relates to a mechanical process for separating metal from slag from metallurgical furnaces.

As is well known, the slag produced in various smelting furnaces, both electric and any other type, contains more or less particles of metal containing or not containing iron, which were entrained by it during the manufacturing process.

The enormous cost of energy today and the possibility of reusing the material with new technologies, the lack of space for landfills and environmental laws make this process very interesting, as it solves several problems by itself, namely:

- idle operation of the furnace can be justified according to the invention at very low cost;

- Up to 98% of the material in the slag can be returned;

-decreased the volume of landfills, given that when working on the invention process, ground slag can be sold as a filler for concrete, as well as a material for filling the base in road construction, as well as an additive (mainly slag) in the production of cement of the type R.A;

The fineness of the resulting metal and its quality do not deteriorate, provided that they are not chemically treated.

The use of metal particles carried away by slag in metallurgical furnaces to date, due to the cheapness of energy, the existence of highly uncontrolled landfills and the absence of environmental protection laws, has been uninteresting for industry.

Accordingly, this single operation of metallurgical furnaces was not used, since the costs are high, not to mention that the existing processes for the recovery of metal from slag required chemical treatment, which reduces the quality of the regenerated metal.

Closest to the proposed method is a method for separating metals from slag from metallurgical furnaces, including crushing the starting material, primary sorting of crushed) material by size, and sorting by density.

The disadvantage of this method is the low quality of the resulting products and low profitability.

The aim of the invention is to increase the efficiency and quality of reclaimed metal.

In FIG. 1 is a block diagram of a mechanical process plant for processing metal-containing slag.

The mechanical process of metal separation proposed by the invention is based on separation by density difference between the slag and the recovered material.

As long as the density difference

more than 6%, we can guarantee successful work.

The process is divided into two stages. In the first step, the metal is freed of its slag by grinding with a crusher, which should be of the so-called double-effect type available on the market to avoid wear, since most casting slag is abrasive.

Primary sorting is then performed to remove a fraction with grain sizes from 0 to 7 mm, which will be collected in a hopper, which the applicant calls concentration feed. The rest of the

The material is passed, depending on the size, at the exit of the primary crushing, to one of several mills, which can be either hammer mills or conical, until the granule sizes become 40 mm or less. Sorting is again done to separate material with a particle size of 0-7 mm, and they are sent to a concentration feed hopper and the rest to a separation feed hopper.

The release of metal from slag has already been achieved at this first stage, with the formation of two sets of material: the first with a size of 0-7 mm, and the second more than 7 mm and less than 40 mm.

This range between 7 and 40 mm can have different sizes for each type of slag, with the preliminary grinding and determination using the magnifier or a microscope of the best size,

in which metal is released.

According to the chosen size

particles, choose one or another sieve in a box for density separation or a separator for this, which we will discuss

below.

If the metal has been freed from its slag, the second stage begins, in which the separation of metal from crushed slag will go. The milled material with dimensions greater than 7 mm, which is located in the corresponding hopper, passes to a separator, consisting of a density separator, through a conveyor belt, with an adjustable feed from the separation plant itself. It mixes with water

by means of a screw processor, it is washed and the sludge which is obtained is removed. In turn, this processor serves as a feeder for the density separator, giving a constant flow of material, and consistency is very important for good separation. Feed adjustment is made in relation to the amount of metal that enters the slag. The operator can adjust the flow at the inlet of the density separation unit.

The density separation separator, or density box, which is known on the market as a ripple box or REMEM has three outlets that are operable to clean it at the bottom thereof.

In the front part, with the help of a small hopper, the already separated material is discharged into the corresponding mu. From this small hopper, separated metal is obtained with particle sizes of more than 7 mm and a content of 90% of the released metal.

A concentrate with particle sizes less than 7 mm with a metal content of 60% is obtained from yields or purifications.

This material is sent to a hopper, which the applicant previously called a concentration hopper, where there is slag milled to a size of 0-7 mm.

A density separator similar to the previous one, but much smaller, with a sieve whose size is less than 0.5 mm, is also fed from this hopper with a controlled feed. A metal with a grain size of 0.5-7 mm with a purity of 95-98% is obtained from the front small hopper of this separator, and a metal with a maximum grain size of 0.5 mm with a purity of 98% is obtained from the separator,

The metal-free slag passes to the screw processors, from where it leaves completely dry and goes to sequential sorting plants, from which slag of various groups of grain sizes is obtained for their subsequent use in construction.

Since the separation process is purely mechanical and the main element of regeneration is water, the cost savings are significant. It can be argued that the energy cost of the separation process is only 5% of what is required for grinding.

In order to avoid a large flow of water, it can be recycled using the advantage of such recirculation to purify the water through the sludge in the tank, from which sludge is removed and removed to the designated place. This or, in some cases, may contain metal in micron fractions, a metal that can be regenerated by any type of vibrating table on the market.

The mechanical process for separating metals from slag exiting metallurgical furnaces, which the invention proposes, includes a slag hopper 1 from which material is led to a crusher 2 and a grading 3, which removes a fraction that passes through a sieve towards the hopper 4.

0 Material that does not pass through the sieve of unit 3 is ground in a mill 5 until particles of less than 40 mm are obtained. Material that passes through a sorting sieve 6 and has granules less than 7 mm,

5 is also removed into the same hopper 4. The remaining material with particle sizes between 7 and 40 mm passes into the hopper 7.

Ground slag with particle sizes greater than 7 mm, which is in the hopper

0 7 passes to a separator 8 in which the metal is separated from the slag based on the density difference. Through a small hopper, metal particles with a size of more than 7 mm are sent to mu 9, while a concentrate with dimensions

5 particles of less than 7 mm with a metal content of 60% are also sent to hopper 4, where there is slag, milled to sizes between 0 and 7 mm.

The material from this hopper A is sent to another separator 10 with a sieve having a mesh size of less than 0.5 mm, from which metal with a particle size of 0.5 to 7 mm is obtained from the small front hopper, and metal with a maximum particle size of 0, 5 mm from

5 purifications and is collected in I 11.

The metal-free slag obtained in separators 8 and 10, after it is completely dried, passes through various sorting plants to obtain

0 fractions of various sizes for use in construction. It gathers at max 12.13 and 14, respectively.

The location chosen to collect sludge leaving separators 8 and 10 is shown.

5 by position number 15.

Claims (1)

SUMMARY OF THE INVENTION A method for mechanically separating metals from slag of metallurgical furnaces, comprising crushing the starting material, primary sorting of crushed material by size, sorting by density, characterized in that, in order to increase the efficiency of the process and the quality of the recovered metal, 5, primary sorting is carried out by 7 mm particle size to obtain a class of 0-7 mm, which is sent to the hopper, and 7 mm class, which is ground in one or several mills to a particle size of not more than 40 mm, and re-sorted by 7 mm particle size, the class of 0-7 mm of re-sorting is sent to the hopper with the same class obtained after the initial sorting, and the class of 40-7 mm is sent to the additional hopper, and the density is subjected to sorting by density from the additional hopper to obtain metal with a size of 7 mm and with a metal content of 90%, which is sent to mu and concentrate with a grain size of 7 mm with a metal content of 60%, which is sent to a hopper for class 0-7 mm after initial sorting, while the material density is separated from this hopper in an additional separator similar to the previous density separator, but with a mesh size of less than 0.5 mm, to produce metal with a grain size of 0.5-7 mm with a metal content of 95-98% from the front small hopper and metal with a grain size of 0.5 mm and a metal content of 98% and slag, which is fed to several screw processors for drying, after which it is divided into fractions according to size for use in construction.