RU2377324C2 - Reprocessing method of metallurgical slags and process line (versions) for its implementation - Google Patents

Abstract

FIELD: metallurgy. ^ SUBSTANCE: invention relates to ferrous metallurgy field, particularly to reprocessing of metallurgical slag, used in building industry, particularly in highway engineering, in concreting and others, to receiving or enrichment of magnetic iron-containing product, used in blast-furnace melting for changing of iron-ore raw material, in melting of steel and at manufacturing of agglomeration. ^ EFFECT: invention provides total reprocessing of running and blade blast-furnace and steelmaking slag, including low-enriched blade nonstandard magnetic product, with receiving of cheap iron-ore raw material with qualitative characteristic, high-grade breakstone of fractions 5-10 mm, 10-20 mm, or mixture of fractions 5-20 mm, 20-40 mm, 40-70 mm, and sand of fraction 0-5 mm. ^ 5 cl, 2 dwg, 2 ex

Description

Technical field

The invention relates to the field of ferrous metallurgy, and in particular to a method for processing slag from metallurgical production used in the construction industry, in particular in road construction, in concrete work, etc., to the production or enrichment of a magnetic iron-containing product used in blast-furnace smelting to replace iron ore, in steelmaking and in the production of sinter.

State of the art

A known method of processing metallurgical slag, including crushing slag, size classification, metal separation by screening and magnetic separation (AS USSR No. 947214, IPC S22B 34/22, BI No. 28, 1982). However, in the known method, the principle of wet grinding is used.

OJSC “Chusovskoy Metallurgical Plant” operates a complex of plants for processing current and dump blast furnace slag (UPSh-1 and UPSh-2), which produce the following products:

- crushed stone fractions 5-20 mm, 20-40 mm, 40-70 mm (commercial products);

- crushed stone fraction 0-5 mm (sand);

- metal concentrate fractions 0-250 mm.

In view of the high content of SiO ₂ , Al ₂ O ₃ , MgO, TiO _2, and other oxides, metallurgical slags (blast furnace and steelmaking) are highly abrasive materials.

The products obtained after processing of blast furnace and steelmaking slag must comply with the requirements established in GOST 5578-94 “Crushed stone and sand from slag of ferrous and non-ferrous metallurgy for concrete” and GOST 3344-83 “Crushed stone and sand slag for road construction”, TU 0798-006 -00186341-2002 "Metal concentrate (blast furnace metal waste)."

The closest in technical essence and the achieved result to the proposed technical solution (both for the method and the device) is the method and production line for processing metallurgical slag (Yu.S. Tleugabulov, K.B. Tleugabulova, A.N. Adamchuk “Metal from slags of blast furnace smelting of titanomagnetites. G. Market of secondary metals, 2002, No. 2, pp. 10-15). The prototype method of processing metallurgical slag includes preliminary screening with separation of the original slag by size and separation of oversized pieces of slag, crushing of slag, screening, magnetic separation by drum iron separators.

At Chusovskaya Metallurgical Plant OJSC, the metallurgical slag processing complex includes two production lines UPSh-1 and UPSh-2, including: a receiving hopper of the UPSh-1 technological line, a feeder, seven belt conveyors, four of which are equipped with drum separators; fixed grate screen (if necessary, the screening surface of the screen is blocked by a steel sheet to direct the entire flow to the UPSh-2 installation), a two-screen inclined inertial screen, a single-screen inclined inertial screen, a belt conveyor connecting the UPSh-1 with UPSh-2, the SMD-109A jaw crusher with a receiving hopper of the UPSh-2 technological line, four belt conveyors, one of which is equipped with a drum iron separator, a three-screen inclined inertial screen, conical warehouses of finished products (substandard according to holding iron of a magnetic product fr. 0-250 mm; sand and crushed stone fr. 0-5 mm, 5-20 mm, 20-40 mm, 40-70 mm).

A drawback of the existing processing technology is that the existing UPSh-1 and UPSh-2 plants are designed and operate according to the technological scheme in an open cycle, which significantly limits the ability to control the outputs of finished products of various sizes and does not allow to increase the production volumes of crushed stone fractions that are in demand the market. The consequence of this drawback of the existing technology, as well as the fact that the technology does not use a crushing and grinding machine and separation equipment that is not optimal for the characteristics of the material, is the inability to obtain a concentrated iron-containing magnetic product, crushed stone and sand with the required quality characteristics for the iron content. The mechanism of the metal phase entering the slag and the properties of the magnetic product are due to the specifics of blast furnace smelting of titanomagnetites and the peculiarities of steel smelting technology. As a result, the titanic blast furnace slag contains an increased amount of metallic inclusions, and the magnetic product extracted from the slag has a high slag content (60% or more).

The high slagging of the resulting magnetic product is due to the fact that it includes the so-called grenal, which is formed in the process of melting between cast iron and slag in the form of a heterogeneous layer of metal droplets coated with titanium carbonitride, the gaps between the metal droplets are filled with slag. The uniform distribution of the metal phase in the volume of the crushed lump of slag leads to the fact that a large amount of slag is involved in the magnetic product.

Due to the high proportion of slag (60% or more) containing 10-11% titanium oxide, the resulting magnetic product is not in demand either on the iron ore raw materials market or in its own metallurgical processes and, as a result, is stored, requiring ever greater storage space, which is the main problem in the processing of blast furnace slag. Each month the warehouse receives additionally (depending on work on current or dump blast furnace slag) from 1000 to 2000 tons of magnetic product.

Disclosure of invention

The objective of the invention is to develop a simple and effective method for processing metallurgical slag, free from the disadvantages of the prototype and the creation of a high-performance production line for its implementation.

The problem is solved using the characteristics indicated in the 1st claim that are common with the prototype, such as a method for processing metallurgical slag, including preliminary screening with the release of oversized pieces of slag, magnetic separation by the first drum separator, crushing slag in a jaw crusher, while the crushed product is subjected to magnetic separation using a second drum iron separator with separation of the magnetic product and non-magnetic product and the classification of non-magnetic product, and distinctive, essential features, such as additional crushing on a centrifugal impact crusher and magnetic separation of a magnetic product or magnetic product and over-screening products of screening a non-magnetic product, isolation of a commodity magnetic product and its classification by size and return of non-magnetic products of additional crushing to the second drum iron separator.

According to claim 2, the magnetic separation before and after additional crushing is carried out using suspended self-discharging iron separators.

In paragraph 3 of the formula, it is noted that the selected commercial magnetic product is screened on a screen to obtain fractionated commercial magnetic products.

The task (according to the first option) is solved using the characteristics specified in the 4th paragraph of the claims, common with the prototype, such as a line for processing metallurgical slag, containing a receiving hopper with a grate installed during the process and interconnected by transport communications for separating oversized pieces of slag and a belt feeder, a first drum iron separator mounted on a conveyor, a jaw crusher, a second drum iron separator mounted on a conveyor l, the roar and floor warehouses of the finished product of crushed stone, sand and commercial magnetic product, and distinctive, essential features such as it is equipped with an additional crushing and magnetic separation installation, which includes a conveyor for transporting the magnetic product and over-screen products of screening the non-magnetic product for additional crushing, installed above self-unloading suspended iron separator, centrifugal impact crusher, conveyor returning products of additional crushing to the drum Nome separators crashing for separating magnetic commodity product and fractionated commercial warehouses magnetic product.

The task (according to the second option) is solved using the characteristics specified in the 5th claim that are common with the prototype, such as a line for processing metallurgical slag containing a receiving hopper installed along the process and connected by transport communications, installed on the conveyor the first drum separator, a jaw crusher, the second drum separator installed on the conveyor, the first screen and floor warehouses of finished products of crushed stone, sand and goods og magnetic product, and distinctive, essential features such as it is equipped with a vibratory feeder with a grate for unloading the receiving hopper and highlighting oversized pieces installed behind the receiving hopper, a second and third screen to separate respectively the magnetic product and non-magnetic product into two fractions, installed after the first drum separator, the fourth screen associated with the first screen through a conveyor belt, and is equipped with an additional crusher magnetic separation, including a conveyor for transporting a magnetic product and over-screening products for screening a non-magnetic product for additional crushing, a suspended self-unloading iron separator, a centrifugal impact crusher, a conveyor for transporting magnetic separation products and additional crushing, a conveyor for transporting a magnetic separation product and additional crushing, mounted over a conveyor for hanging a self-unloading iron separator, a return conveyor non-magnetic products of additional crushing to drum iron separation Yeh-lii crashing for separating magnetic commodity product fraction and fractionated commercial warehouses magnetic product.

The above set of essential features both in the method and in the device (technological line - options) allows to obtain the following technical result during the implementation of the invention - complete processing of current and dump metallurgical (blast and steelmaking) slags, including a low enriched dump substandard magnetic product, with obtaining cheap iron-containing raw materials with quality characteristics not lower than that purchased from iron ore raw materials (iron ore), high-quality th gravel fractions 5-10 mm, 10-20 mm (or mixture of fractions of 5-20 mm), 20-40 mm, 40-70 mm and the sand fraction 0-5 mm. In this case, by mixing a commercial magnetic product of fractions of 10-70 (40; 50; 60) mm and 70 (40; 50; 60) -300 mm in the required proportions, metallurgical charge material with a grain size of 10-300 mm with the necessary content of metallic iron can be obtained and total iron (including oxidized iron). Commercial magnetic product fraction 0-10 mm is a high-quality charge material for use in sinter production.

The environmental component of the technical result is the reduction in the area of dumps, the reduction of the harmful effects on the environment, the release of land and its restoration, and the involvement of technogenic raw materials in the production.

The technical result is achieved through the construction of a new production line (figure 2) or the reconstruction of the existing production line with the installation of additional units for the secondary crushing of slag on UPSh-2 (figure 1).

The technical result is achieved due to the rational layout and application of new high-tech equipment, fundamentally different from the existing on the prototype slag processing.

Processing of metallurgical slag consists in obtaining finished products — a commercial magnetic product with a high content of metallic iron and total iron, and crushed stone and sand with a minimum content of metallic iron, which is a harmful impurity in crushed stone and sand.

As shown by experimental work, at an additional stage of crushing metallurgical slag, especially high-titanium blast furnace (in which the mass fraction of TiO ₂ is up to 13%), it is advisable to use crushing and grinding equipment, which uses the principle of impact destruction of the material, such as centrifugal impact crushers . Centrifugal impact crushers are optimal machines for the stage of fine crushing, in which at the same time crushing and grinding operations of almost any, including hard-to-work abrasive materials, are carried out by applying the principle of crushing “stone on stone”. It allows you to crush and grind both ore and non-metallic materials, physically-mechanical indicators suitable for the characteristics of crushers and with a SiO ₂ content of up to 100%.

The use of a centrifugal impact crusher allows you to:

- crush materials of any strength;

- receive the product in a wide range of fineness;

- to obtain cube-shaped crushed stone with the content of lamellar and needle-shaped particles in the range of 5-15% (1 group according to GOST 8267-93, change No. 3 from 01.07.02);

- increase the grade of crushed stone obtained after crushing by strength and abrasion by one step due to selective grinding by weak grains, phase boundaries, and grain size;

- provide high crushing performance;

- significantly increase the degree of crushing and expand the range of regulation of the content of fractions in the product;

- reduce capital costs due to low material consumption and lack of foundations;

- reduce operating costs;

- to obtain a stable particle size distribution of the crushed product, not depending on the wear of the lining elements;

- exclude dynamic balancing of accelerators.

To effectively separate metal inclusions of both large and smallest sizes on the production line, the authors proposed the installation of suspended self-unloading magnetic iron separators (separators).

General conditions for the process.

Processing of metallurgical slag consists in preliminary screening and separation of oversized pieces of slag, preliminary magnetic separation, two-stage crushing, followed by magnetic separation and screening to produce finished products - marketable magnetic product with a high content of metallic iron and total iron, and crushed stone and sand with a minimum metallic content iron, which is a harmful impurity in rubble and sand.

The magnetic separation of the charge is carried out at all stages of crushing and grinding stage using drum separators in the first and second stages and suspended self-unloading iron separators in the final stage.

The following are specific examples of the invention.

The proposed processing line for the processing of metallurgical slag according to the first embodiment is presented in the diagram (figure 1).

Example 1

The metallurgical slag processing line contains a receiving hopper 1 installed along the technological process and interconnected by transport communications with a grate for separating oversized slag pieces and a belt feeder, a first drum iron separator 2 installed on the conveyor, and a second drum iron separator 4 mounted on the conveyor , screen 5, open floor warehouses of finished products of crushed stone 6, sand 7 and commercial magnetic product 8. The line is equipped with an additional installation crushing and magnetic separation 9, which contains a conveyor for transporting magnetic products or magnetic products and non-magnetic over-screening products for additional crushing 10, mounted above the conveyor 10, a suspended self-unloading iron separator 11, a centrifugal impact crusher 12, a conveyor for transporting products of magnetic separation and additional crushing 13 mounted above the conveyor 13 suspended self-unloading iron separator 14, the conveyor 15 return non-magnetic products will complement crushing to the drum iron separator 4, a screen for separating the selected commodity magnetic product into fractions 16, and warehouses of a fractionated commodity magnetic product 17.

Installation work.

The initial product is fed into the receiving hopper 1 of the production line UPSh-2. From the receiving hopper 1, the initial product wakes up in the SMD-109A 3 jaw crusher, the width of the discharge gap of which is regulated depending on the material being processed.

After passing through the crusher 3, the material with a particle size of 0-70 mm is fed via a conveyor belt to the additional crushing and magnetic separation unit 9. An electromagnetic separator pulley 4 is installed as a drive drum of this conveyor. An electromagnetic product 4–70 mm in size is separated from the product by an electromagnetic iron separator 4 that enters the conveyor belt 10.

A non-magnetic product with a particle size of 0-70 mm is fed to a three-screen inclined inertial screen 5 with a mesh size of 40x40 mm, 20x20 mm, 5 × 5 mm, where the material is divided into four fractions according to the size of the pieces and particles.

The crushed stone of the 5-20 mm fraction obtained after sieving on the screen 5, using, for example, a conveyor belt, enters the finished product warehouse 6.

The crushed stone of fractions 40-70 mm, 20-40 mm obtained after sieving on the screen 5 at the corresponding positions of the sliders of the flow unit of the screen 5 is sent to the conveyor of the additional crushing unit, or, for example, it is conveyed to the finished goods warehouse 6 using conveyors.

Sand of a fraction of 0-5 mm accumulates in the finished goods warehouse 7 under a roar of 5, then it is shipped by a loader into a motor vehicle.

The crushed stone of fractions 40-70 mm, 20-40 mm and the magnetic product received on conveyor 10 are fed for secondary crushing (finishing) in the centrifugal impact crusher DC-1.6 12.

Above the conveyor 10, a suspended self-unloading iron separator 11 is installed, configured to remove from the slag stream a magnetic product with the required iron content, which are dumped onto the conveyor 13.

The product obtained after passing through the DC-1.6 centrifugal impact crusher 12 through the conveyor 13 is sent to the conveyor 15, along with which the product with a grain size of 0-70 mm received on the SMD-109A 3 crusher is fed to the sieve for a three-sieve inertial screen 5.

Above the conveyor 13, a suspended self-unloading iron separator 14 is installed, configured to remove from the slag stream a salable magnetic product with the required iron content.

Crushed stone of fraction 5-20 mm obtained after sieving on screen 5, using, for example, a conveyor, arrives at the finished goods warehouse 7.

The crushed stone of fractions of 40-70 mm, 20-40 mm obtained after sieving on the screen 12, with the appropriate positions of the sliders of the flow unit of the screen 5, is sent to the conveyor 10 for additional crushing, or, for example, it is fed to the finished goods warehouse 6, depending on selected production pattern.

A commodity magnetic product removed from the stream by means of a suspended self-unloading iron separator 14 with the required iron content is fed to a fixed grate screen 16 with a distance between grates 10 mm, where the obtained commodity magnetic product is divided into fractions 0-10 mm and 10-70 mm. Commodity magnetic product fr. 0-10 mm and fr. 10-70 mm are accumulated separately under the grate rumble in the warehouses of a commodity magnetic product 17 and are shipped to consumers with a front-end loader.

Preliminary preparation of the metal-slag mass is carried out on the existing plant for the processing of slag UPSh-1.

Oversized pieces of slag are processed separately at the battle site.

The proposed production line for the processing of metallurgical slag according to the second embodiment is presented in the diagram (figure 2).

Example 2

The metallurgical slag processing line contains a receiving hopper 1 installed during the technological process and interconnected by transport communications, a first drum iron separator 2 mounted on the conveyor, a jaw crusher 3, a second drum iron separator 4 mounted on the conveyor, screen 5, open floor storage facilities for crushed stone finished products 6, sand 7 and commercial magnetic product 8. The line is equipped with a vibratory feeder 9 with a grate for unloading the hopper and highlighting oversized pieces and a receiving hopper 1, a second 10 and a third screen 11 for separating the magnetic and non-magnetic products, respectively, into two fractions, installed after the first drum separator 2, the fourth screen 12, connected with the first screen 5 through a conveyor belt 13. Additionally equipped with an additional crushing unit and magnetic separation 14, which contains a conveyor for transporting magnetic products or magnetic products and non-magnetic oversize screening products 15 for additional crushing, a suspended self-discharging iron separator 16, a centrifugal impact crusher 17, a conveyor for transporting magnetic separation products and additional crushing 18 mounted on a conveyor 18, a suspended self-unloading iron separator 19, a conveyor 20 for returning non-magnetic additional crushing products to a drum iron separator 4, a screen for commodity separation magnetic product in fraction 21, and warehouses of fractionated commercial magnetic product 22.

Installation work.

The initial product is fed into the receiving hopper 1 of the installation. From the hopper 1 using a vibratory feeder with a grate 9, the initial slag metal mass is fed to a stationary grate 11 with a mesh size of 300 mm. The oversize product (piece size over 300 mm) is fed to the oversized warehouse, the oversize product is fed, for example, to a conveyor belt (B = 1000 mm). An electromagnetic pulley electromagnetic pulley EMSh-10100 2 is installed as a drive drum of this conveyor. The magnetic product is fed to the screen grate DRO 633-10 11, where it is divided into fractions 0-70 mm and more than 70 mm. The magnetic product of a fraction of more than 70 mm enters the open floor conical warehouse of the magnetic product 8, and the magnetic product fr. 0-70 mm is fed by a conveyor belt to the additional crushing and magnetic separation unit 9. The slag part is fed to the grate screen 11, where it is sieved into fractions of 0-70 mm and more than 70 mm. A slag fraction of 70 mm enters the SMD-109A 3 jaw crusher, and a fraction of 0-70 mm, using a conveyor belt, into an additional crushing and magnetic separation unit 9. An electromagnetic pulley electromagnetic pulley EMSh-10100 4 is installed as a drive drum of this conveyor, which separates the slag mass on slag and magnetic products. The magnetic product enters the conveyor belt 15 of the additional crushing and separation unit 9, the slag product is fed to the GIT-32M 5 screen, where it is divided into three fractions - 40-70, 20-40 and 0-20 mm. Crushed stone of fraction 40-70 mm is fed using a conveyor belt to the finished goods warehouse 7. Slag crushed stone of fraction 40-70 mm is fed using a belt conveyor to the finished goods warehouse 7. In case of overfilling of finished goods warehouses 7 of the above fractions, they are fed through a gate to conveyor 15 for its further crushing in a centrifugal impact mill ДЦ - 1.6 17. The under-sieve product (slag mass fraction 0-20 mm) from screen 5 is fed by belt conveyor to a double-screen screen GIT-42M 12. Sifting products of this g rumble is crushed stone fractions 5-10, 10-20 mm and sand fractions 0-5 mm. These fractions are conveyed by belt conveyors to the cones of the finished goods warehouse 6, 7.

The magnetic product (slag metal mass) of the 0-70 mm fraction is conveyed by belt conveyor 15 for secondary crushing into the DC-1.6 centrifugal impact crusher 17. Before unloading this stream into the DC-1.6 centrifugal impact crusher, the magnetic product with the required content is removed from the stream iron using a suspended self-unloading iron separator 16, excluding its ingress into the crusher 17. This magnetic product enters the belt conveyor 18. The non-magnetic product enters the additional crushing and then to the belts primary conveyor 18. Above the drive drum of the conveyor belt 18, a self-unloading iron separator 19 is mounted on the overflow conveyor 20. The magnetic product is fed to a stationary grate screen 21 with a distance between grates of 10 mm, at which it is sieved into fractions 0-10 and 10 -70 mm (fractions of a commodity magnetic product). The non-magnetic product from the conveyor 20 is returned to magnetic separation using an electromagnetic pulley EMSh-10100 4 iron separator and secondary screening on a GIT-32M 5 screen.

Obtaining a magnetic product of the required quality is achieved by adjusting the following parameters of suspended self-unloading iron separators, namely:

the ability to change the distance from the separators to the moving stream;

the ability to change the suspension angle of the separators to the flow;

the ability to change the installation angle of the adjustment gate.

A magnetic product of the required quality is fed to the sieve to obtain fractions of a commercial magnetic product 0-10 and 10-70 mm, and a non-magnetic and weakly magnetic product is returned to the cycle.

Oversized pieces of slag are processed separately at the battle site. Previously, they are crushed using a ball-woman, then, using a crane electromagnetic washer, large metal inclusions are removed from the treated metal-slag mass. After that, the prepared slag mass is sent to the receiving hopper of the plant for processing metallurgical slag.

This arrangement of the apparatus chain allows you to process the original slag of blast furnace and steelmaking both separately from the magnetic product extracted on UPSh-1 and UPSh-2, and together.

According to this technology, it is possible to enrich the metal screening obtained at the MPCS (processing open-hearth and partially blast furnace slag) and the metal screening from the processing of converter slag obtained in the ferroalloy shop. As transport communications as part of the technological equipment of the above technological lines contain belt conveyors.

The proposed production lines and method for processing metallurgical slag is underway at OJSC Chusovskaya Metallurgical Plant.

From the description and practical application of the present invention, specialists will be obvious and other private forms of its implementation. This description and examples are considered as material illustrating the invention, the essence of which and the scope of patent claims are defined in the following claims, a combination of essential features and their equivalents.

Claims (5)

1. A method of processing metallurgical slag, including preliminary screening with the allocation of oversized pieces of slag, magnetic separation by a first drum iron separator, crushing the slag in a jaw crusher, while the crushed product is subjected to a second drum iron separator with magnetic separation with separation of the magnetic product and non-magnetic product and non-magnetic screening product, characterized in that they carry out additional crushing on a centrifugal impact crusher and magnetic separation of ma Product-magnetic or magnetic product and oversize product of screening non-magnetic product, isolation magnetic commodity product and its classification according to size and returns nonmagnetic additional cleavage products to the second drum separators. 2. The method according to claim 1, characterized in that before and after additional crushing, magnetic separation is carried out using suspended self-unloading iron separators. 3. The method according to claim 1, characterized in that the selected commercial magnetic product is screened on a screen to produce two fractionated commercial magnetic products. 4. A line for processing metallurgical slag, containing a receiving hopper with a grate for separating oversized pieces of slag and a belt feeder installed on the conveyor during the technological process and interconnected by transport communications, a first drum separator installed on the conveyor, a second drum separator installed on the conveyor, rumble and floor warehouses of finished products of crushed stone, sand and commercial magnetic product, characterized in that it is equipped with an additional installation crushing and magnetic separation, which includes a conveyor for transporting a magnetic product and over-screening products for screening a non-magnetic product for additional crushing, a suspended self-unloading iron separator, a centrifugal impact crusher, a conveyor for returning non-magnetic products of additional crushing to a drum iron separator, a screen for separating a commodity magnetic product, mounted above the conveyor and warehouses of fractionated commercial magnetic product. 5. A line for processing metallurgical slag, containing a receiving hopper installed during the technological process and interconnected by transport communications, a first drum separator installed on the conveyor, a jaw crusher, a second drum separator installed on the conveyor, the first screen and floor warehouses for finished products of crushed stone, sand and commercial magnetic product, characterized in that it is equipped with a vibratory feeder with a grate for unloading the receiving hopper and highlighted oversized pieces installed behind the receiving hopper, the second and third screens for separating the magnetic product and non-magnetic product, respectively, into two fractions, installed after the first drum separator, the fourth screen connected with the first screen through a conveyor belt, and also equipped with an additional crushing unit and magnetic separation, including conveyor for transporting the magnetic product and over-screening products of screening a non-magnetic product for additional crushed a suspended self-unloading iron separator installed above the conveyor, a centrifugal impact crusher, a magnetic separation products conveyor and additional crushing conveyor, a self-unloading suspended iron separator conveyor installed above the conveyor, a non-magnetic additional crushing return conveyor to the drum iron separator, a screen to separate commercial magnetic product into fractions and warehouses finished fractionated commercial magnetic product.

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