HK1261565A1 - A method of preparing a fine particle metal mixture comprising crushing residues with a high portion of viscoplastic components and an apparatus used for the method - Google Patents

Description

Method and device for producing a fine-grained metal mixture with a partially high proportion of a cohesive-plastic constituent of a comminuted residue

Technical Field

The invention relates to a method according to the features of claim 1 and a system according to the features of claim 8.

The method and system can be used anywhere on fine particles, brittle refractory minerals and metal-containing components, containing a mixture of shredded residues with a high proportion of viscoplastic components, and providing material recovery. This applies in particular to the shredded residues in the disposal of scrap vehicles, mixed and collective wastes.

Background

German patent DE 19911010 a1 describes a system and a method for processing comminuted waste, such as composite materials, and the use of a rotor impact mill. The introductory part of this patent specification discusses the amount of material recovered in the recovery of scrapped vehicles and its composition and proposes the use of rotor impact mills, air sieves and sieve classification. It is stated in the document that non-ferrous metals (NE) are normally recovered from heavy materials after treatment in a pulper by means of a vortex separator, an air separation stage or a water trough/float system. The lightweight material after treatment by the pulper mainly consists of a pulped product consisting of plastic, rubber, wood, textiles, foamed plastic, glass, soil and stones. As described in the document, the disposal and recovery of shredded waste materials is extremely difficult, since they carry harmful substances. In most cases, these harmful substances include: .

-polychlorinated biphenyl (PCB): 1 to 12mg/kg

-Polycyclic Aromatic Hydrocarbons (PAH): 10 to 200mg/kg

-other Hydrocarbons (HC): 10 to 40 mg/kg.

This is not the subject of the present document, which contains part of the highly viscoplastic components and concerns the material in the form of fine particles and containing a mixture of metal components of brittle minerals. According to the proposed method and the apparatus, these materials cannot be successfully recycled, in particular if it is desired to completely reduce the size of the brittle fine-grained mineral to a size of 3 to 5mm, preferably below 4 mm.

Disclosure of Invention

The object of the present invention is therefore to develop a method and an apparatus with which the size of the brittle fine-grained mineral of the shredded residues from scrapped vehicles, mixed and collective waste treatment can be completely reduced to less than 4 mm.

This object is achieved by a method as characterized by the features of claim 1 and by an apparatus as characterized by the features of claim 8. Advantageous embodiments of the invention are set forth in the dependent claims.

The solution of the invention provides a method for the preparation of fine-grained metal mixtures in a plant, which mixtures comprise the intermediate products of the pulped residue (pulper treated light material SLF/pulper treated heavy material SSF) and other treated waste vehicles, mixed and collective wastes with respect to components having a high proportion of viscoplastic properties. In the batch mode process, the feed is pre-sorted to 40-60mm, preferably 50mm, and then manually sorted to remove >40-50mm metal content, preferably greater than 50mm metal content. Wherein non-metallic components >50mm together with <50mm sieved fraction impart a rapid impact stress. And a further sieving classification of 3-5mm, preferably 4mm, and a pneumatic classification of <7m/s is carried out in a plurality of cycles until the finely divided friable mineral is completely separated from the coarser metal content.

Since large objects may be present in the feed, a screening classification of 40-60mm, preferably 50mm, size is carried out in each case. This process may be used to protect the shredder from damage.

Studies on the preparation of fine-grained metal mixtures with a partly high proportion of cohesive-plastic constituents of the comminuted residues have shown that without any pulper, the feed containing mineral constituents can be shredded and separated to below 4mm without continuous cyclic action of screening and inspection. Even multiple passes through the pulper without intermediate screening and inspection are not effective for waste recovery.

An advantageous embodiment of the process is that the feed presorting of 40 to 60, preferably 50mm, takes place only in the first cycle.

The first circulation is understood to be the feed path through the first screening classification, the crushing, the second screening classification and the pneumatic classification to an intermediate bunker for collecting the residual mineral-containing material to be treated. The intermediate bunker may also be understood as a feed hopper from which the feed is conveyed in a subsequent cycle for the comminution operation. The number of cycles may be between 2 and 5.

In each cycle, the newly formed light material in the form of mineral fines will be sieved at a speed <7m/s and discharged into a collection container.

If the mineral content of the product of the sieve classification is greater than 4mm, the material is only passed once more after the last cycle, while all the product is collected in a separate container after the second sieve classification and after the pneumatic classification.

An advantageous embodiment of the process is a rapid impact comminution of the comminuted product of the second sieve classification in the range of 3 to 5mm, preferably 4mm, the coarse material of the sieve classification being collected in an intermediate silo in each cycle.

The classified product of >4mm is fed 2-5 times, preferably 3 times, in a cyclic operation (U1 to U3) together with the corresponding heavy material of the screened fraction of <4mm screened on an intermediate silo.

Another advantageous embodiment of the method is that after one or more circulation operations, a further through-flow (D4) is carried out, wherein the material flow of the coarse material of >4mm is classified by means of a sieve and the pneumatic classification product (heavy material SG and light material LG) formed at an air speed of 5 to 7m/s, preferably 7m/s is conveyed into a collection container in each case.

Furthermore, it is advantageous to collect in each cycle in the same intermediate silo >4mm of the second sieve sorted coarse material and >7m/s of the pneumatically sorted heavy material and repeat, preferably three cycles.

In each cycle, only the pneumatically classified light material is removed from the cycle and fed into the collection container Box 3.

Furthermore, it is advantageous to introduce the coarse material of the sieve classification produced after the last conveying pass as end product into a separate collection vessel 2A/2B. It should be a number of collection containers that can be interchanged once filled.

Only with this method brittle fine-grained minerals can be crushed to below 4mm so that they can be completely removed from the process as mineral material and stored by pneumatic classification (light materials LG <7 m/s).

The apparatus for carrying out the method provides a screening classifier with a 40-60mm, preferably 50mm screen plate located upstream of an impact mill, wherein the screening classifier is connected to a manual sorting station by a conveyor. Thus, it is possible to presortion the material to be sieved which is >40-60mm, preferably 50 mm. Hand picking is used to remove larger steel and non-ferrous metals from the process.

A conveying device arranged between the hand picking and the impact mill conveys the hand picked residues to the impact mill together with <40-60mm, preferably <50mm, of the sorted material after sieving.

The impact mill is followed by a further screen classifier having 3-5mm, preferably 4mm screen plates, the coarse material of which is returned by a conveyor to the impact mill or to a storage container in the circulation.

The fines sieved through <3-5mm, preferably <4mm, are fed by means of a conveyor to a pneumatic classification system with an air velocity vL between 5-7m/s, in particular 7 m/s.

Furthermore, a conveying device for the impact mill is provided for feeding the second classified coarse material into the circuit.

The other storage containers of the plant are for containing the final product after pneumatic classification (light material <7m/s, heavy material >7 m/s).

The solution according to the invention has the following advantages: the brittle mineral component is completely separated from the coarser metal fraction from a mixture of fine-grained metal shredder residues and discarded vehicles, mixed and collective waste-treated products with a partially high proportion of viscoplastic components.

Suitable conveying devices include belt conveyors, bucket elevators, screw conveyors or chain conveyors.

Suitable storage containers include silos, containers, material tanks, silos or sacks.

It is also advantageous to use several zigzag sifter units for pneumatic classification in order to achieve as low a specific solids attachment as possible in the zigzag sifter (ZZS). This can be achieved by using 2-4 zigzag sifters (ZZS).

Furthermore, it is an advantageous measure to provide a dosing bin between the sifting classification and the pneumatic classification. By the proposed method, a high proportion of fine material <4mm on the sieve classification can be formed at a selected feed and delivery quantity, which can be stored before sieving. The use of several, preferably three, sieves connected in parallel helps to solve the problem.

Drawings

FIG. 1 is a schematic view of the apparatus of the present invention.

Detailed Description

The invention is described in further detail below with reference to the accompanying examples.

FIG. 1 is a schematic view of the apparatus of the present invention in which the operation of crushing and separating the brittle components of the feed material is performed.

Although the present embodiment relates only to the most advantageous screening classifier width, air velocity, number of circulations and zigzag sifters (ZZS), this is of course applicable to the other described screening classifier widths, circulations or air velocities without further elaboration.

Brittle components are primarily materials containing mineral components, such as glass, ceramics, stone and metallurgical slags. The crushing operation is performed by means of an impact mill with a vertical rotor shaft, which, however, imparts the feed several times. Thus, the system operates in a batch mode in a cyclic operation (2-5 cycles per feed). The feeds were classified according to their size classification (SGK) into the following 3 groups, each as follows:

group 1: 8mm

Group 2: 30mm

Group 3: 60mm of SGK 30

The wheel loader moves the feed material through a feed bin which is removed from the stock of raw material and fed into the apparatus. From the silo the material is metered onto a conveyor belt FB1 and conveyed to the first screen classifier, which classifies the material to 50 mm. In the processing of groups 1 and 2, only small amounts of coarse material (in particular long material) are produced, which are conveyed by the conveyor FB2 into a container. The sorting thereof is carried out separately. Coarse material >50mm in processing group 3 is likewise (reversibly) fed via conveyor belt FB2 to the downstream hand sorting station. This procedure becomes particularly important in this case, assuming that the proportion of >50mm coarse material in group 3 is 20-40% of the feed. In group 3, only solid metal pieces were removed to protect downstream shredding components from damage. The remaining unsorted material will be sent to conveyor FB 3. For all three material groups, the fines of the sieve classification (machine) 1 are also fed to the conveyor belt FB3 by a conveyor belt FB4, which conveyor belt FB3 acts as the feed belt of the vertical impact mill. However, the conveying mode of the screening and sorting (machine) 1 and the hand sorting station is only carried out in the first circulation U1. In the following cycle U2, U3, the material is conveyed directly to the pulper (type: rotor impact pulper) via conveying sections FS6 and FS10 consisting of a conveyor belt, a bucket elevator and an intermediate bunker. Where selective comminution of the brittle component will occur. The discharge of the crushed material is performed by means of a chain conveyor TKF5, which provides material to the second screening classifier TKF 5. The sieving classifier (machine) 2 classifies the crushed material having a mesh size of 4 mm. The coarse material formed in each cycle is transferred to the intermediate silo via the transfer section FS6 and stored. After the intermediate bunker has been filled with sieve overflow and pneumatically classified heavy material three times by means of the circulation operations U1 to U3, only one more pass-through D4 is carried out by means of crushing, sieving and pneumatic classification, the product P4, coarse material >4mm and pneumatically classified light and heavy material being supplied to a storage vessel by means of the selected conveyor assemblies FS11, FS 9, FS12, respectively. The fines <4mm (passage) of the sieve classifier (2) are fed to a dosing silo via a conveyor belt FB7 consisting of a screw conveyor and a bucket elevator. The batching silo delivers and distributes the material by means of the conveyor line SF8 through three screw conveyors to a pneumatic classification system consisting of three zigzag sifters (ZZS) and observation channels, a rotary valve, a cyclone separator and a fan. In the zigzag sifter (ZZS), mineral fine-grained components (sifted light material) are to be separated. The screened lightweight material (LG) is removed from the process during each cycle and fed through a conveyor line FS 9 consisting of a conveyor screw and a conveyor belt of the collection container (Box 3). The screened lightweight material (LG) is removed from the process during each cycle and fed to a collection container (Box3) by a conveyor belt FS 9 consisting of a screw conveyor and a conveyor belt. The sieved heavy material produced in the zigzag sifter (ZZS) is conveyed in the first three cycles by a screw conveyor to a feed collection conveyor (coarse discharge) and likewise by a conveyor belt and a bucket elevator to an intermediate silo for subsequent repetition of the crushing and sorting procedure. However, this subsequent cycle only starts when the silo of the previous cycle has been completely emptied. This procedure will be repeated several times until after cycle 4 the coarse material >4mm and the screened heavy material >7m/s is removed from the procedure as a finished product. The finished screened heavy material >7m/s is the highest recoverable component with no insulated cables and other composite materials. The overflow of the finished screen is more than 4mm, most of the finished screen does not contain mineral components, and the content of the finished screen is less than 0.5 percent. The light material of the sieve with classification product <4mm is mainly composed of mineral components with non-ferrous metals content < 0.1%.

Larger size material >4mm screened sorter (machine) 2 will be (reversibly) fed by conveyor belt to distribution conveyor (FS11), which distribution/conveyor (FS11) temporarily stores the material in collection container (Box2A/2B) before further processing. The final screened heavy material of the last cycle >7m/s will be fed by means of a screw conveyor, a bucket elevator and a conveyor belt (FS12) to a collection container (Box 1) and thus temporarily stored for further processing.

Due to the large amount of fines generated, the entire process is equipped with a dust removal system. The exhaust gas purification is carried out in a central filter. The resulting dust will be collected in a big bag and disposed of.

Claims (10)

1. A process for the preparation of a fine-grained metal mixture comprising the steps of grinding the residue (SLF after treatment with a grinder/SSF after treatment with a grinder) and other intermediate products treated in connection with scrapped vehicles having a high proportion of viscoplastic components, mixing and collecting the waste, it has the functions of classification, impact stress, pneumatic classification, transportation, storage and the like, and is characterized in that, in the batch mode, the feed is pre-classified to 40-60mm, then the metal content in the coarse material is removed by manual sorting, wherein the non-metallic components of the coarse material together with the majority of the fine material classified by the screen impart a rapid impact stress, and multiple cycles of 3-5mm further sieve classification and multiple cycles of <7m/s pneumatic classification are carried out until the finely divided brittle mineral fraction is completely separated from the coarser metal content.

2. Method according to claim 1, characterized in that the presorting of the feed material of 40-60mm is carried out only during the first cycle.

3. A method according to any of claims 1-2, characterized in that the fast impact stressed pulped product is subjected to a sieve classification 2, and the coarse material is collected in an intermediate bin and recirculated 2-5 times per cycle.

4. A method according to any of the claims 1 to 3, characterized in that the pneumatically classified heavy material from the fines of the screen classification 2 is collected in each circulation in the same intermediate silo and is carried out three times in the circulation (U1-U3).

5. A method according to any of claims 1 to 4, characterized in that in each cycle U1 to U3, only pneumatically classified light materials are removed from the cycle and transferred to a collection vessel (Box 3).

6. A method according to any of claims 1 to 5, characterized in that the final coarse material of the screened fraction 2 produced after the third cycle and a through-feed (D4) is fed into a separate collection container (Box 2A/2B).

7. The method as claimed in any of claims 1 to 6, characterised in that the pneumatically classified final heavy material produced in the third circulation (U3) and the fines of the screened classification 2 produced after a through-feed (D4) is fed as finished product (P4) to a separate collection vessel (Box 1), in which the light material can be treated together with the light material already separated in the circulation U1 to U3.

8. An apparatus for performing the method according to the features of claims 1 to 7, characterized in that:

-a screening classifier (machine) with a 40-60mm screening deck located upstream of an impact mill, wherein said screening classifier (machine) is connected to a manual picking station by means of a conveyor (FB 2);

-a conveying device (FB3) is arranged between the manual picking station and the impact mill;

-said impact mill is connected downstream with another screening classifier having a 3-5mm screening deck;

-a conveyor (FS6) is arranged between the overflow of the sifting and sorting machine (2) and the intermediate bin;

-a conveying device (FB3) is arranged between the intermediate bin and the impact mill;

-the <3-5mm fines of the sieving classification (machine) 2 are conveyed by a conveyor (FS8) to a sieving machine at a sieving wind speed vL of less than 7 m/s;

-a conveying device (FS 10; SF6) is arranged between the screen and the impact mill for guiding heavy material through the intermediate bin in a circulating operation (U1 to U3); and

-a further storage container (Box 2A/2B; Box 1; Box3) which stores the final through-conveyed end product (P4, LG), i.e. the heavy goods of >34mm coarse material, light material and sifter which are stored in the sifting classifier (machine) 2.

9. An apparatus as claimed in claim 8, characterized in that a conveyor belt, a screw conveyor and/or a trough chain conveyor is provided as the conveying means.

10. Apparatus according to claims 8 and 9, characterized in that as sifter there are provided three zigzag sifter units connected in parallel.