Process for producing high-purity scrap materials from inhomogeneous input material

Abstract

To provide an improved process for producing recycled scrap which makes it possible to obtain, from an inhomogeneous starting material with special handling challenges, a particularly pure scrap product having a particularly advantageous bulk density.SOLUTION: A production process comprises: a) a step of preparing or providing an inhomogeneous, ferrous scrap mixture; b) a comminution step of comminuting it in a comminution unit so as to obtain a comminuted material; c) a separation step of separating organic and / or inorganic impurities from the comminuted material in order to obtain a pre-purified material; d) an analysis and removal step of analyzing the pre-purified material with one or more first detection devices so as to detect at least one first item of material information, and removing constituents of the pre-purified material according to the information so as to obtain a purified material; e) an analysis step of analyzing the purified material with one or more second detection devices in order to detect at least one second item of material information; and f) a comparison step of comparing the second item of material information with an associated material criterion, so that the purified material is output if the second item of material information fulfils the criterion.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a process for producing recycled scrap, to recycled scrap with a particularly high iron content that can be produced by said process, to a scrap recycling plant optimized for carrying out said process, and to an improved crushing section for use in said process and plant.

[0002] The subject matter of the present invention is defined in the appended claims. [Background technology]

[0003] Valuable scrap is obtained by scrapping used metal products. Iron and steel scrap in particular have long been considered not only waste but also important secondary raw materials, which can be used in a variety of applications, reducing the need for newly manufactured metals. Using scrap as a raw material not only reduces an industry's reliance on scarce raw materials, but also reduces the amount of unnecessary waste. Large-scale industrial production of metals and alloys generally requires large amounts of energy and resources, so reducing the demand for new production also contributes to a more sustainable economy.

[0004] Particularly in the field of manufacturing products for high-performance applications, particularly high demands are placed on iron-containing scrap: if scrap is used instead of newly produced metal, it must ensure that it has material properties at least approximately equivalent to those of the newly recovered metal.

[0005] Therefore, in principle, there is a high demand for pure scrap mixtures in many industrial applications, and ideally scrap mixtures with favorable packing densities are also desirable. However, this is notoriously difficult to achieve, as the raw materials for producing such scrap mixtures are inherently heterogeneous. For example, scrapping washing machines from two different manufacturers may result in scrap with different properties, despite being similar products.

[0006] The prior art discloses various methods for obtaining such pure scrap mixtures, but these methods are generally very complicated and essentially involve manual sorting processes by workers to isolate the particularly suitable fractions from the scrap mixture.

[0007] In large, industrial-scale shredder plants, to practically achieve the production of a relatively pure scrap mixture, operators often pass the processed scrap repeatedly through the processing plant and shredder, i.e., subjecting the scrap to multiple comminution steps and, if necessary, downstream sorting operations, in an effort to achieve higher purity of material and / or advantageous packing densities. Summary of the Invention [Problem to be solved by the invention]

[0008] The processes known from the prior art have the disadvantage that they are relatively time-consuming and / or expensive, for example, because they require the material to be processed twice, which increases waste and reduces the material throughput of the plant by at least half. Furthermore, these processes can result in material remaining in the plant during the second pass through the plant, having only reached the discharge point of the first pass. This can result in a certain fraction of the material being removed from the outlet, which has not yet been subjected to the necessary second shredding step.

[0009] Furthermore, prior art processes often suffer from a relatively small amount of data on the resulting products, which is problematic because it is not enough to simply provide scrap of a particular quality for a high-end application; it is often essential that that quality can also be properly proven, for example from a liability perspective.

[0010] It is also often difficult in processes known from the prior art to actively control the product quality during operation of the process, for example in order to adapt the process to customer requirements as quickly as possible, so that in processes known from the prior art it is often not possible, for example, to produce two different specifications of scrap products one after the other in continuous operation and / or without modifying the plant.

[0011] Additionally, conventional techniques often do not allow for the production of products with the high packing densities advantageous for certain applications within production times that are efficient for large-scale industrial production. [Means for solving the problem]

[0012] A primary object of the present invention is to demonstrate an improved process for recycling scrap that can eliminate or at least reduce the shortcomings of the prior art.

[0013] It is therefore an object of the present invention to provide an improved process for the production of recycled scrap of high quality and high packing density, which makes it possible to produce a particularly pure scrap product with a particularly advantageous packing density from common scrap fractions, i.e. from raw materials that are heterogeneous and particularly difficult to handle.

[0014] The objective of this invention is to demonstrate a recycled scrap manufacturing process that produces correspondingly high quality products, ideally in only one pass, and that is time and cost efficient for large scale industrial scale manufacturing to produce these high quality scrap products in large quantities at low cost.

[0015] Compared to the prior art, the explicit recycled scrap manufacturing process should in particular make it possible to achieve significantly higher purities in industrially relevant quantities than have been possible with previous processes.

[0016] As a supplementary requirement, the manufacturing process for the express recycled scrap must be capable of being carried out using conventional scrap fractions as raw materials and, as far as possible, using the equipment available in conventional scrap processing plants.

[0017] An additional object of the present invention is to enable a defined recycling scrap manufacturing process to automatically provide more comprehensive information about the physical properties of each case scrap batch produced.

[0018] Furthermore, the explicit recycled scrap production process must be flexible and easily adaptable, adapting particularly efficiently to changes in customer quality requirements, ideally even during operation. In this respect, a supplementary object of the present invention is to make the explicit recycled scrap production process flexible in adapting the chemical composition and / or particle shape and / or packing density of the recycled material.

[0019] Additionally, a process for producing explicitly recycled scrap is desirable, particularly to reduce the risk of producing a defective scrap batch that cannot be used by the customer.

[0020] A further object of the invention is to make the explicit recycled scrap production process particularly safe to operate with low emissions, reducing safety risks and contamination of people and the environment.

[0021] Furthermore, a secondary object of the present invention is to demonstrate high quality recycled scrap suitable for high performance applications.

[0022] A further secondary object of the present invention is to specify an improved scrap recycling plant and a novel crushing section, each optimized for use in the specified processes.

[0023] The inventors of the present invention have developed a novel and powerful process and associated plant that achieves the aforementioned objectives. In summary, the process of the present invention is based on comprehensive modifications of existing process technology, emphasizing a unique combination of screening techniques using process analysis as defined in the claims. [Effects of the Invention]

[0024] The process of the present invention, for the first time known to the inventors, allows industrially relevant quantities of high-quality scrap products to be produced in a time- and cost-effective manner in a single pass. Even using heterogeneous raw materials, i.e., common scrap fractions, it is possible to produce iron contents of 97% or more and advantageous packing densities while substantially eliminating organic impurities, something the inventors have not been able to achieve using similar prior art large-scale industrial processes, at least with comparable material throughput and / or reproducibility. As a synergistic advantage, material information obtained during the manufacturing process can be used to document the characteristics of the material, allowing the scrap products produced to be certified with little effort.

[0025] Experiments carried out by the inventors have shown that recycled scrap products with an iron content of more than 97% can be obtained on a large industrial scale, and furthermore, by using a suitable plant according to the invention, the packing density of the roughly spherical particles can be increased to about 1.5 t / m 3 We were able to obtain recycled scrap products.

[0026] The above-mentioned object can therefore be achieved by a process for producing recycled scrap, scrap that can be produced using said process, a plant for recycling scrap, and a crushing unit as defined in the claims. Preferred embodiments of the invention are evident from the dependent claims and the following description. DETAILED DESCRIPTION OF THE INVENTION

[0027] The preferred embodiments of the present invention described below are particularly preferred in combination with other preferred features. Therefore, it is highly preferred to combine two or more of the particularly preferred embodiments described below. Similarly, it is preferred to combine a feature that is less preferred with one or more other features that are less preferred. The features of the preferred recycled scrap, the preferred scrap recycling plant, and the preferred crushing unit are clear from the features of the preferred process.

[0028] The present invention provides a) a process for producing or supplying a heterogeneous mixture of iron-containing scrap; b) grinding the heterogeneous iron-containing scrap mixture in a grinding section to obtain a ground material; c) a screening step for separating organic and / or inorganic impurities from the ground material to obtain a pre-purified material; d) analyzing the pre-purified material using one or more first detection devices to detect at least one first material information, and removing components of the pre-purified material based on the first material information to obtain a purified material; and e) analyzing the purified material with one or more second detection devices to detect at least one second material signature; f) a comparison step of comparing the detected second material information with a predetermined material standard assigned to the second material information, wherein the refined material is extracted as recycled scrap if the second material information satisfies the assigned predetermined material standard.

[0029] The process of the present invention is fundamentally suitable for small-scale production. Therefore, it has been demonstrated that the process of the present invention can produce excellent scrap products, even in pilot-scale plants. However, at low throughput rates, the process of the present invention becomes increasingly economically competitive with more complex manual processes. For example, physicochemical separation of scrap mixtures on a laboratory scale may also provide a pure scrap product. The process of the present invention is particularly preferred for large-scale industrial processes, as it offers significant advantages in such processes. It is highly preferred that the process of the present invention be performed at a rate of 30,000 kg or more of recycled scrap per hour, preferably 60,000 kg or more, and particularly preferably 75,000 kg or more. As those skilled in the art will recognize, large-scale industrial-scale implementation, especially at specified actual throughput rates, places particularly high demands on the process, the equipment used, and the raw materials. This widens the range of options, which, for example, increases the demand for scrap materials to produce heterogeneous iron-containing scrap, often resulting in increased heterogeneity of the raw materials.

[0030] In step a) of the process of the present invention, a heterogeneous iron-containing scrap mixture is provided or produced directly in said process.

[0031] In actual production, for example, several iron-containing scrap fractions may be mixed. To achieve this, for example, the various scrap fractions may be fed successively in significant amounts into the crushing section or may be fed simultaneously into the feed opening of the crushing section so that they reach the crushing section at the same time. This production method has proven to be particularly efficient in practice. The incorporation of the mixing of several scrap fractions into the process is advantageous because the composition of the mixture can be controlled by adapting the mixing ratio. Therefore, in the process of the present invention, the production of the heterogeneous iron-containing scrap mixture in step a) is preferably carried out by mixing several iron-containing scrap fractions to form scrap, and more preferably, this mixing is carried out substantially in the crushing section.

[0032] The term scrap fraction is clear to those skilled in the art of metal processing, and they can easily distinguish between different iron-containing scrap fractions. Scrap fractions are typically collections of homogeneous objects collected according to detailed selection criteria, pooled, and / or processed together.

[0033] The mixture of different iron-containing scrap fractions may vary according to changing legal provisions and industry-specific specifications. Those skilled in the art will inevitably distinguish between, for example, scrap fractions consisting of so-called white goods (e.g. washing machines, ovens, etc.) and scrap fractions consisting of, for example, pressed car bodies or factory scrap arising from metalworking operations.

[0034] As will be appreciated by those skilled in the art, the iron-bearing scrap fraction is a grading standard for collecting ideal homogeneous scrap, and although in most cases scrap mixtures are heterogeneous as well, the scrap present in said scrap fraction has smaller deviations in material properties than scrap from secondary iron-bearing scrap fractions or other similar scrap. In practice, the fractions in question are usually collected separately according to appropriate regulations and stored separately by the users.

[0035] In the inventors' experiments, a wide range of common scrap fractions have been used to produce heterogeneous iron-containing scrap mixtures. Certain scrap fractions are particularly advantageous due to their availability and relatively high iron content. In the preferred process of the present invention, one or more iron-containing scrap fractions selected from the group consisting of industrial scrap, white goods, composite materials, waste incineration scrap, pre-shredder material, and end-of-life vehicle bodies are preferably used. As will be understood by those skilled in the art, the term "white goods" refers to household electrical appliances such as refrigerators, washing machines, dishwashers, and stoves, as distinguished from so-called "black goods," such as televisions and mobile phones. Pre-shredder material is generated, for example, from disposal operations and sorting plants, and often includes, for example, bicycles, sunshades, and similar items.

[0036] The actual mixture of scrap fractions / heterogeneous iron-containing scrap mixture used in the production of the process of the present invention, i.e., the heterogeneous iron-containing scrap mixture, particularly with respect to the mixture of various different parts, has not been conclusively determined. However, since the processing of homogeneous raw materials is significantly less desirable, the iron-containing scrap mixture should be heterogeneous in the present invention. This criterion can be easily determined by those skilled in the art in practice. As will be understood by those skilled in the art, an iron-containing scrap mixture is considered heterogeneous if it is produced by mixing several iron-containing scrap fractions and / or if it contains fractions obtained by scrapping several different types of articles selected from the group consisting of white goods household appliances, car bodies, and waste from metalworking operations.

[0037] In step b) of the process of the invention, the iron-containing scrap mixture is pulverized. In the present invention, this pulverization is carried out by a pulverizer. Step b) therefore corresponds, for example, to the shredding steps known to the skilled person from the prior art.

[0038] Various grinding units can be used, such as scrap shears, Kondirator crushers, and Zerdirator crushers, but the use of shredders or Zerdirator crushers has proven particularly advantageous for processing large amounts of material. In the present invention, a Zerdirator crusher refers to a grinding unit with a ground material discharge area, typically covered with an iron grate, at the bottom of the grinding chamber. Zendirator crushers may also optionally have an additional discharge area at the top of the grinding chamber. In contrast, the term shredder refers to a grinding unit that does not have a ground material discharge area at the bottom of the grinding chamber, but has a ground material discharge area, typically covered with an iron grate, at the top of the grinding chamber.

[0039] It is highly preferred that the grinding section used in the present invention is constructed with a movable base plate and / or cover plate that allows for the change of the outlet through which particles can be discharged from the grinding chamber.

[0040] This reduces the amount of ground particles discharged and increases the average residence time of the particles in the grinding section. This advantageously allows for control of the grinding intensity from the outside, even during operation. By increasing the average residence time, the discharge area may be temporarily completely closed, allowing for an increase in the refining capacity and / or a reduction in particle size and packing density, depending on the requirements and demands. Therefore, it is obviously preferred in the process of the present invention that the grinding chamber of the grinding section comprises at least one discharge area for the ground material, in which a movable element, preferably a movable base and / or cover plate, particularly preferably a hydraulically movable base and / or cover plate, is provided, by means of which the outlet through which the particles can be discharged from the grinding chamber can be changed.

[0041] The inventors of the present invention have concluded that, to make the aforementioned processing mode possible, it is most advantageous to mount a movable base plate and / or cover plate, for example, inside or outside the grinding chamber, preferably outside. The movable elements are preferably remotely movable. In view of the above, it is basically preferred in step b) of the inventive process to control the mean particle size of the ground material by controlling the residence time, in particular the mean residence time, of the scrap mixture in the grinding section using movable elements installed in the discharge area.

[0042] When the crushing section is a shredder, it is preferred that at least one movable element, e.g., a movable lid, be provided in the upper discharge area of ​​the crushing chamber. When the crushing section is a Zerdirator crusher, it is preferred that at least one movable element be provided in the bottom discharge area of ​​the crushing chamber. However, the preferred crushing section of the present invention is highly preferred to use a crushing section in which at least one first movable element is provided in the upper discharge area of ​​the crushing chamber and a second movable element is provided in the bottom discharge area of ​​the crushing chamber. The residence time of the scrap mixture in the crushing section can be advantageously controlled by using two different movable elements, but it can also be advantageously controlled by moving the movable element located in the lower discharge area to completely close the bottom discharge area of ​​the crushing chamber. This advantageously allows the crushing section to be flexibly operated as both a Zerdirator crusher and a shredder. For example, difficult-to-process scrap mixtures can be crushed in shredder mode with the substrate closed. On the other hand, for relatively easy-to-process scrap mixtures, particularly those containing metal plates, it is possible to open the substrate and operate in Zerdirator crusher mode to increase throughput.

[0043] The inventors of the present invention have found particularly suitable operating parameters for the milling section, according to which in the process of the present invention the hammer rotors of the milling section are driven by an electric motor, the output power of which is preferably greater than 2,000 kW, particularly preferably greater than 2,400 kW, and very particularly preferably greater than 2,800 kW.

[0044] In particular, in the case of a high material throughput, a large amount of dust may be generated in step b). In particular, in the processing mode that controls the outlet through which particles can be discharged from the grinding chamber, it is possible to achieve particle sizes that are somewhat smaller than those achievable with conventional methods, even with continuous operation. Therefore, dust problems are particularly common in the process of the present invention. Based on the inventor's own experiments, the present inventors propose providing a dust removal unit directly in the grinding unit to minimize environmental pollution. Therefore, in the process of the present invention, it is preferred that the grinding unit include a dust removal unit, preferably a dry dust removal unit, preferably a dry dust removal unit equipped with one or more activated carbon filters.

[0045] In step c), a first treatment step is carried out to remove organic and / or inorganic impurities from the ground material obtained from the grinding section. This screening step is also found in some prior art processes, but in most cases the treatment is carried out in a single, relatively simple device.

[0046] This screening advantageously captures as many impurities as possible that are generally visible to the naked eye. As will be understood by those skilled in the art, step c) is not defined as screening out all impurities, but rather as at least a partial screening. In the process of the present invention, the inorganic impurities are preferably metallic or mineral impurities, more preferably metallic impurities.

[0047] While manual sorting in step c) is at least theoretically possible, for example by conveyor belt sorting, this would be labor intensive, particularly for large-scale industrial scrap processing such as the present invention, and would therefore be uneconomical, at least in most industrialized countries. Therefore, in the process of the present invention, it is preferred that the sorting in step c) is carried out using one or more sorting devices, preferably automated sorting devices.

[0048] The inventors of the present invention have found that, among other separation processes, separation processes are particularly suitable for the process of the present invention. These suitable separation processes include length separation, air separation, magnetic separation, and sieving. These separation methods, and the equipment used, are generally known to those skilled in the art.

[0049] In order to optimize the quality of the resulting scrap product, the inventors of the present invention propose to combine several of these operating steps.Accordingly, in the process of the present invention, the separation of organic and / or metallic impurities in step c) preferably comprises two or more, preferably three or more, particularly preferably four or more different operating steps selected from the group consisting of length separation, air separation, magnetic separation and sieving separation.

[0050] The inventors of the present invention have found, through experiments carried out to date, a configuration that is particularly suitable for the process and plant of the present invention, which places emphasis on achieving the highest possible product quality for recycled scrap, without taking into account cost-effectiveness issues. In the inventors' opinion, the separation of organic and / or metallic impurities in the process of the present invention preferably includes length separation, preferably air separation using air sifters including multiple cascades, magnetic separation, and sieving separation, performed in this order. In the magnetic separation, it is preferable to use two or more magnetic separators, preferably electromagnets, and it is particularly preferable that the magnetic field strength of the electromagnets is adjustable.

[0051] A unique feature of the process of the present invention is that the pre-purified material obtained in step c), i.e. the ground material from which organic and / or inorganic impurities have been at least partially removed, is analyzed in step d) using a first detection device.

[0052] At least one material characteristic, preferably two or more material characteristics, is detected, i.e., the pre-purified material is automatically inspected after pre-purification. In most cases, the first material characteristic thus measured is selected to correlate with the chemical composition and / or particle shape and / or particle size of the pre-purified material. The material characteristic may be, for example, a spectroscopic measurement or an optical image obtained from the pre-purified material.

[0053] Subsequently, the components of the pre-purified material are removed according to the material information detected in step d). That is, for example, if the first material information does not meet predetermined criteria or specifications, for example, regarding chemical composition or shape, a fraction contained in the purified material is removed based on the material information. Step d) of the process of the present invention refers to the entire removal with the aid of a detection device. As a detection device, any detection device known to those skilled in the art, in particular spectroscopic and optical detection devices, may be used.

[0054] As a result of the previous sorting, the number of destructive particles to be removed is usually relatively small, so that, at least in theory, the removal in step d) seems feasible to perform manually. In this case, if the first material information is displayed to the operator, for example, on a monitor or other interface, the operator can easily obtain information about the fraction of the pre-purified material to be removed. However, from the viewpoint of the achievable material throughput and, in particular, the accuracy of the sorting, it is clearly preferable to perform the sorting automatically. In his own plant, the inventors have succeeded in finding particularly sophisticated devices connected to the first detection device, for example, via a data processing device or a network. In the process of the present invention, the sorting in step d) is preferably performed using an automated device, preferably, for example, a rod-shaped compressed air gun equipped with multiple compressed air nozzles or a robotic arm, and particularly preferably, using a robotic arm.

[0055] In the process of the present invention, the material thus purified passes through a further detection device which detects at least one second material signature, preferably two or more, and in this case compares this second material signature with the corresponding material signature or with a material standard assigned to each material signature, i.e., for example, by comparing a spectroscopically measured value with a threshold value or by comparing an optically measured particle shape with an accepted particle shape template.

[0056] In the process of the present invention, only if the second material information meets the assigned predetermined material criteria is the refined material discharged as recycled scrap, i.e., as a product that can be transported, for example, by conveyor belt, to an appropriate storage facility. Otherwise, the refined material is, for example, discarded, transported to a downstream plant for further processing, or processed again by the process of the present invention, the latter being generally preferred. From an efficiency standpoint, it is advantageous to process the recycle in step c) or step d) without returning it to the crushing section. Therefore, in the process of the present invention, it is preferred to process refined materials in which at least one second material information does not meet the predetermined material criteria again in step b), step c), or step d).

[0057] The comparison is preferably carried out by a data processing device, for example a computer, and therefore in the process of the present invention the predetermined material criteria are preferably transmitted to the data processing device and / or retrieved from memory.

[0058] In the process of the present invention, it is preferable that the refined material is discharged as recycling scrap when all the second material information satisfies the predetermined material criteria assigned thereto.

[0059] The analyses of steps d) and e) have many similarities.

[0060] For an efficient processing mode in a preferred continuous or semi-continuous process, it is desirable that the detection device also operates continuously. In the process of the present invention, it is preferred that the analysis of step d) and / or step e), preferably the analysis of steps d) and e), is carried out continuously, in particular in-line.

[0061] In order to achieve the best possible material properties, in particular to simultaneously optimize the iron content, the content of organic impurities, and / or the particle shape, it has proven particularly advantageous for the first and / or second detection devices to independently detect multiple pieces of material information. Therefore, in the process of the present invention, it is preferred to detect at least two, preferably at least three, pieces of first material information in step d) and / or to detect at least two, preferably at least three, pieces of second material information in step e). It is also preferred in the process of the present invention that at least one piece of first material information and / or at least one piece of second material information, preferably all pieces of material information, are correlated with the chemical composition and / or particle shape and / or mechanical properties, preferably the chemical composition, of the analyzed material.

[0062] To this end, in most processes of the present invention, it is preferred that at least one of the first material information and at least one of the second material information correlate with particle properties of the same material.

[0063] In the opinion of the inventors of the present invention, spatially and / or temporally resolved detection is particularly advantageous, depending in particular on the configuration of the remaining plant and whether the plant is operated continuously. Such a resolution is particularly advantageous in step d), since it allows for accurate removal of impurities and minimizes material waste. Such a resolution is also advantageous in step e), since deviations from the material standard may be, for example, partial, and at least a fraction of the purified material may be discharged as recycled scrap. In continuous or semi-continuous operation of the process, temporal resolution also allows for correlation of the material information with the respective fraction of recycled scrap discharged. Therefore, in the process of the present invention, it is preferred to detect at least one first material information and / or at least one second material information, preferably all material information, in a spatially and / or temporally resolved manner, resulting in spatially and / or temporally resolved profile information in each case. Therefore, it is also preferred in the process of the present invention that the analysis of steps d) and / or e), preferably steps d) and e), is performed using a spatially and temporally resolved measurement method.

[0064] Furthermore, this preferred processing mode synergistically allows the measured material information, in particular the secondary material information, to be simultaneously used for the specification, certification and authentication of the discharged recycled scrap, which also allows the latter to be used in applications where there are high demands on the scrap product, in particular for safety reasons.

[0065] In the process of the present invention, it is preferred to store at least one first material information and / or at least one second material information, preferably at least one second material information, in a memory of the data processing device, and further preferably to correlate this material information with at least one operational information, preferably one temporal information, so that the respective material information is assigned to the discharged recyclable scrap fraction, and the respective material information is preferably assigned to the respective discharged recyclable scrap fraction by means of a certificate, preferably a digital certificate.

[0066] Through experiments, the inventors of the present invention have been able to identify particularly suitable detection methods / accompanying detection devices. These methods result in excellent purity, and the use of multiple methods for each measurement has proven to be particularly effective. In the process of the present invention, the analysis of step d) and / or step e), preferably steps d) and e), is preferably carried out using one or more, preferably two or more different methods selected from the group consisting of X-ray fluorescence analysis, optical image recognition, preferably optical image recognition using artificial intelligence, and infrared absorption spectroscopy, especially near-infrared absorption spectroscopy. X-ray fluorescence analysis is used, for example, to determine the content of elements, and infrared / near-infrared absorption spectroscopy is used, for example, to determine the content of organic substances.

[0067] In principle, the same type of detection device can be used in steps d) and e), thereby detecting the same type of measurement value as the first and second material information, or acquiring the first and second material information in the same data format, such as an image. However, the inventors of the present invention have found that using different detection methods is effective, especially when used to detect material information correlated with the same material or particle properties. This minimizes measurement errors and synergistically allows the different methods to compensate for each other's shortcomings and improve processing accuracy. Therefore, in the process of the present invention, it is preferable to detect the first and second material information using different detection methods, preferably when the first and second material information are correlated with the same material or particle properties.

[0068] As mentioned above, it is believed that a major advantage of the process of the present invention is that it can be operated continuously with good results, thereby providing a particularly time- and cost-efficient processing mode. It is therefore highly preferred that the process of the present invention is a continuous or semi-continuous process, and it is even more preferred that at least a portion of the ground material and / or pre-refined material and / or refined material, preferably all of these materials, is conveyed using conveyor belts and / or vibrating conveyors.

[0069] The process of the present invention advantageously allows for obtaining large amounts of recycled scrap that reproducibly exhibit particularly advantageous iron content, shape factor, and / or packing density, and therefore is particularly advantageous in the process of the present invention when performed to achieve the corresponding parameters, which makes the advantages over the prior art clear.

[0070] In the process of the present invention, it is preferred that the maximum particle size of the recycled scrap is 100 mm or less, preferably 80 mm or less, and particularly preferably 60 mm or less.

[0071] In the process of the present invention, the average particle size of the recycled scrap is preferably within the range of 60 to 250 mm, more preferably 80 to 200 mm, and particularly preferably 100 to 150 mm.

[0072] In the process of the present invention, the average shape factor of the length divided by the width of the recycled scrap is preferably in the range of 1 to 5, preferably 1 to 2.5, more preferably 1 to 1.25, and it is highly preferred that the particles of the recycled scrap are approximately spherical.

[0073] In the process of the present invention, the packing density of the recycled scrap is 1.0 t / m 3 More than 1.2t / m 3 More than 1.5 t / m, particularly preferably 1.5 t / m 3 More preferably, it is equal to or greater than this.

[0074] Furthermore, in the process of the present invention, it is preferred that the iron content of the recycled scrap is 97% or more, preferably 98% or more, more preferably 99% or more, based on the mass of the recycled scrap.

[0075] Starting from the process that has been invented, the inventors of the present invention have discovered particularly advantageous developments in the interaction of the process with the configuration of the present invention. Three so-called feedbacks for controlling and optimizing the process are now described.

[0076] The first two feedbacks use material information detected during scrap handling in the process of the present invention, and each step of the process of the present invention is controlled according to the recorded material information.

[0077] The process of the present invention preferably comprises a so-called first feedback control, in which the composition of the heterogeneous iron-bearing scrap mixture is controlled in accordance with first and / or second material information, preferably the first and second material information, particularly preferably by changing the mass ratio of a plurality of iron-bearing scrap fractions in the iron-bearing scrap mixture.

[0078] This processing mode allows for active response to deviations in scrap characteristics, particularly chemical composition, and for active control of raw material selection in upstream processes. This is preferably performed using a data processing device, preferably a neural network or equivalent artificial intelligence, preferably a data processing device using a neural network. Furthermore, the data processing device used is preferably trained to record deviations in material information from corresponding predetermined target values, particularly from material standards, and to react by changing the mass ratios of several iron-containing scrap fractions in the production of a heterogeneous iron-containing scrap mixture as an appropriate correction method for the measured deviations. Because the first material information is detected earlier in the process, this first feedback based on the first material information can be advantageous for an earlier response.

[0079] The process of the present invention preferably includes a so-called second feedback control, in which the grinding in step b) is controlled according to the first material information and / or the second material information, preferably the first and second material information, by changing one or more operating parameters of the grinding unit selected from the group consisting of the size of the grinding chamber, the size of the discharge openings in the discharge area, and the speed of the hammer rotors. Although the basic concept is the same as the first feedback control, the second feedback control controls the operating parameters of the grinding unit rather than controlling the composition of the heterogeneous iron-containing scrap mixture according to the detected material information. In controlling the operating parameters of the grinding unit, the size of the particle outlets is a preferred operating variable. The use of this feedback control is particularly effective when the grinding unit of the present invention is used in the process of the present invention. The control of step b) also preferably involves the use of a data processing device, preferably a neural network or equivalent artificial intelligence, preferably a data processing device using a neural network, which is trained to record deviations of the material information from corresponding predetermined target values, in particular material standards, and to modify the operating parameters of the grinding unit as an appropriate correction method for the measured deviations.

[0080] The final third feedback uses material information, but not material information detected during the process of the present invention, but material information detected during additional processing. This detection is performed essentially in the same manner as the detection of the first and second material information described above. This material information is detected from products, such as mixtures and converted products, obtained from the recycled scrap processing, and relates to, for example, material composition and strength. At least one third material information is periodically provided to the operator of the process of the present invention from an external source, such as a customer who receives refrigerant scrap for converters.

[0081] The process of the present invention preferably comprises a so-called third feedback loop, in which at least one third material information is detected during the further processing of the recycled scrap and the components of the heterogeneous iron-bearing scrap mixture, preferably the mass ratio of the iron-bearing scrap fraction in the heterogeneous iron-bearing scrap mixture, as preferably preferred as described above, and / or the comminution in step b), as preferably preferred as described above, and / or the sorting in step c) are controlled according to said at least one third material information, whereby the use of a neural network or an equivalent artificial intelligence, preferably a neural network, is advantageous.

[0082] The process of the present invention preferably includes a first and a second feedback, and particularly preferably includes a first, second and third feedback.

[0083] The present invention further relates to recycled scrap produced or producible by the process of the present invention, which has an iron content of at least 97% by weight, preferably at least 98% by weight, particularly preferably at least 99% by weight, based on the mass of the recycled scrap. Such recycled scrap of the present invention is particularly advantageous, since it is suitable for demanding applications and its quality is almost indistinguishable from that of virgin metal.

[0084] Furthermore, the present invention provides at least one crushing unit, preferably a crushing unit of the present invention, for crushing a heterogeneous iron-containing scrap mixture; a sorting means for sorting organic and / or metallic impurities from the pulverized material; one or more first detection devices that analyze the materials obtained after sorting and detect first material information; an automatic removal means for automatically removing a fraction from the material obtained after sorting according to the first material information; one or more second detection devices that analyze the material obtained after removal to detect second material information; and a data processing device adapted to compare the second material information with an assigned predetermined material standard, and to discharge the material refined by the device as recycled scrap if the second material information satisfies the assigned predetermined material standard.

[0085] The plant of the invention is advantageously suitable for carrying out the process of the invention, and it is particularly preferred that the plant of the invention comprises the additional components necessary for carrying out the process of the invention in a preferred embodiment, in particular specific crushing units, sorting devices, detection devices and data processing devices adapted to realise the above-mentioned first, second and / or third feedback.

[0086] Finally, the present invention provides a grinding chamber having at least one discharge area for ground material; The present invention relates to a grinding unit, preferably for use in the process or plant of the present invention, which comprises at least one hammer rotor installed in the grinding chamber and includes a movable element designed to control the discharge of ground material from the dischargeable grinding chamber in a discharge area. It is also preferred that the grinding unit is provided with a movable base and / or cover plate, particularly preferably a hydraulically movable base and / or cover plate, which can change the discharge of ground particles from the dischargeable grinding chamber in the discharge area.

[0087] As will be appreciated by those skilled in the art, the grinding chamber will generally include an inlet opening for introducing the scrap mixture to be processed into the grinding chamber, separate from the discharge area for the ground material in the present invention.

[0088] The inventive crushing section is optimized for use in the inventive process and is particularly advantageous because it allows the aforementioned control of step b) and the secondary feedback loop to be particularly easily implemented. In contrast to the prior art, the inventive crushing section allows the average residence time of the particles in the crushing chamber to be varied during operation, thereby varying, for example, the particle size and the degree of refinement of the processed scrap.

[0089] The grinding section of the present invention is particularly preferred in that the grinding section at the top of the grinding chamber has a first discharge area with a first movable element designed to control the outlet of the ground material from the grinding chamber, which can be discharged in a first discharge area, and the grinding section at the bottom of the grinding chamber has a second discharge area with a second movable element designed to control the outlet of the ground material from the grinding chamber, which can be discharged in a second discharge area. This is particularly preferred because, for the first time in the inventors' knowledge, this grinding section makes it possible to realize a grinding section that is flexible, i.e., can be switched between a shredder and a Zerdirator crusher even during operation. Therefore, it is particularly preferred that the grinding section of the present invention can be operated as both a shredder and a Zerdirator crusher by moving one or more elements in the discharge area of ​​the grinding chamber.

[0090] In the process of the present invention, which combines one or more of the features of the preferred process described above, it is highly preferred that the grinding section includes a sound-attenuating enclosure.

[0091] In the process of the present invention, which combines one or more of the features of the preferred processes described above, it is highly preferred that the grinding section is anchored in the ground by a foundation.

[0092] In the process of the present invention, which combines one or more of the features of the preferred processes described above, it is highly preferred to weigh the scrap mixture and / or the ground material and / or the pre-refined material and / or the refined material.

[0093] In the process of the present invention, which combines one or more of the features of the preferred process described above, it is highly preferred that the process be controlled by a controller.

[0094] It is highly preferred that the process of the present invention, which combines one or more of the features of the preferred process described above, provides an audible or visual alarm in the event of an anomaly.

[0095] In the process of the present invention, which combines one or more of the features of the preferred process described above, it is highly preferred that the grinding section be made of greater than 75% by weight steel.

[0096] In the process of the present invention, which combines one or more of the features of the preferred process described above, it is highly preferred that the discharged recycled scrap be stored in a repository.

[0097] In the process of the present invention, which combines one or more of the features of the preferred processes described above, it is highly preferred that the discharged recycled scrap be transported on a heavy goods vehicle, railcar or ship, preferably a railcar or ship.

[0098] It is highly preferred that the process of the present invention, which combines one or more of the features of the preferred processes described above, can be interrupted by an emergency switch.

[0099] Highly preferably, the plant of the present invention, which combines one or more of the features of the preferred plants described above, includes a signalling device and / or a warning device.

[0100] It is highly preferred that the plant of the present invention, which combines one or more of the features of the preferred plants described above, includes an emergency switch which will shut down the plant.

[0101] In a plant according to the invention combining one or more of the above preferred plant features, it is highly preferred that the crushing section is made of more than 75% by weight of steel.

[0102] Highly preferably, the plant of the present invention, which combines one or more of the features of the preferred plant described above, includes a control unit for controlling the plant.

[0103] It is highly preferred that the plants of the invention, combining one or more of the features of the preferred plants described above, have an overall length of more than 5m, preferably more than 10m or more, more preferably more than 15m.

[0104] It is highly preferred that the comminution section of the present invention, which combines one or more of the preferred comminution section features described above, has a foundation, preferably a concrete foundation.

[0105] Combining one or more of the preferred grinding section features described above, the grinding section of the present invention highly preferably includes steel hammers.

[0106] Combining one or more of the preferred comminution section features described above, the comminution section of the present invention highly preferably includes an operating means.

[0107] It is highly preferred that a grinding section of the present invention, combining one or more of the preferred grinding section features described above, weighs more than 100 kg, preferably more than 200 kg.

[0108] Combining one or more of the preferred grinding section features described above, the grinding section of the present invention is highly preferably made of greater than 75% by weight steel.

[0109] The following describes preferred embodiments of the process of the present invention, which the inventors have found to be particularly advantageous, and the plant of the present invention for use therein. These preferred embodiments are based on a process for producing a pulverized ... 3 This was discovered through comprehensive optimization of recycled scrap that can be manufactured on a large industrial scale.

[0110] The processed material is transported on a conveyor belt, allowing the process to operate as a continuous process.

[0111] The raw material produced is a heterogeneous mixture of iron-containing scrap, which is produced by mixing multiple iron-containing scrap fractions, such as white goods, industrial scrap, pre-shredded materials, and pressed end-of-life vehicle bodies, at the feed port of the crushing section.

[0112] A heterogeneous iron-containing scrap mixture is crushed in the crushing unit of the present invention shown in Figure 1. The crushing unit is equipped with a hydraulically movable base plate and cover plate, which may be used to change the outlet of crushed material from the dischargeable crushing chamber. This allows the average residence time of particles in the crushing chamber to be controlled, thereby controlling the average particle size of the crushed material. A movable base plate installed at the bottom of the crushing chamber can close the lower discharge area, leaving only the upper discharge area of ​​the crushing chamber open for discharge. Therefore, the crushing unit of the present invention can operate as both a shredder and a Zerdirator crusher. In practical experiments, the crushing unit normally operates as a shredder.

[0113] The crushing section further includes a dry dust removal section including a plurality of activated carbon filters.

[0114] The shredded material is passed through a sorting mechanism to separate organic and inorganic impurities from the comminuted material to obtain a pre-purified material.

[0115] The sorting mechanism includes a series arrangement of a conventional length sorter, a wind shifter including a three-stage cascade, two magnetic separators using adjustable magnetic sorting electromagnets, and a sieve.

[0116] The material stream is analyzed by two first detection devices: a camera that detects shape and size information of fractions in the pre-purified material, and a continuously operating near-infrared spectrometer that measures material information that correlates with the chemical composition of the analyzed material. This spatially and temporally resolved material information is then sent to a computer-controlled robotic sorting device that uses sensor-assisted removal of impurities / fractions identified as not meeting predetermined requirements based on the provided data.

[0117] The purified material is then placed on a conveyor belt and passes through a further area for reanalysis. Detection equipment that can be used here includes X-ray fluorescence spectroscopy in addition to continuously operating near-infrared spectroscopy, which provides additional information about the chemical composition (e.g., particle size rechecks using cameras were not performed in this process, but could be performed). The information recorded in this way is compared with assigned predetermined material criteria, in this case the presence or absence of selected organic and metallic impurities, particularly copper, using a data processing device.

[0118] If all material criteria are met, the resulting material is discharged as recycling scrap and sent to storage on a conveyor belt.

[0119] The detected second material information is stored in a computer and associated with the production / discharge time. This material information is associated with the corresponding batch using a digital certificate, which can later be used by customers to authenticate scrap products for specific applications.

[0120] The plant in question is equipped with computer control means capable of controlling the process according to different feedbacks, i.e., detected material properties. In this embodiment, the operating parameters of the crushing section, more precisely the power in the discharge area and the adjustment of the movable base plate, are controlled according to the first material information detected by the camera. The composition of the heterogeneous iron-containing scrap mixture is changed according to the near-infrared / X-ray fluorescence measurements. In the current stage of development, this adaptation is carried out by visual instructions to the operator of the excavator, which are displayed on a display indicating the amount of scrap fraction to be added. However, automatic feeding is required as a solution.

[0121] The process and plant are adapted to receive third-material information from users of recycled materials and to control the operating parameters of the crushing section and the composition of the heterogeneous iron-bearing scrap mixture according to this third-material information. In the absence of an actual user, this feedback can currently only be verified with simulated experimental data, but the plant is adapted as per the present invention.

[0122] By continuously detecting material information, controlling the process based on this detection, and subsequently detecting it using the same detection means, a comprehensive data set can be advantageously obtained, which allows training of the neural network to provide more accurate feedback and reduce the need for expert empirical knowledge as much as possible.

[0123] The pulverizing unit of the present invention and preferred embodiments thereof will be described in more detail below with reference to the drawings: Figure 1 is a schematic cross-sectional view showing a preferred embodiment of the pulverizing unit of the present invention. [Brief explanation of the drawings]

[0124] [Figure 1] FIG. 1 is a schematic cross-sectional view of a preferred example of the crushing section 10 of the present invention.

[0125] The grinding section 10 is particularly suitable for use in the process of the invention / plant of the invention and comprises a grinding chamber 12 . The grinding chamber 12 includes an inlet opening 22 through which the scrap mixture, supplied by, for example, the conveyor belt 18a, enters the grinding chamber 12. The grinding chamber 12 further includes two discharge areas 14a, 14b.

[0126] The first discharge area 14a is located above the grinding chamber 12 and includes a first movable element 20a designed to restrict the outlet of ground material from the grinding chamber 12 that can be discharged in the first discharge area 14a. In this embodiment, the first movable element 20a is a hydraulically adjustable cover plate. The second discharge area 14b is located at the bottom of the grinding chamber 12 and includes a second movable element 20b designed to restrict the outlet of ground material from the grinding chamber 12 available in the second discharge area 14b. In this embodiment, the second movable element 20b is a hydraulically adjustable base plate formed in two parts like a double-door.

[0127] 1, the mobility of the movable elements 20a, 20b is indicated by double-headed arrows. The discharge areas 14a, 14b are each covered with an iron grate to prevent excessively large particles from leaving the grinding chamber 12. Preferably, the iron grates in the discharge areas 14a, 14b may have an adjustable mesh size and / or may be reversibly and non-destructively replaceable.

[0128] In the crushing chamber 12, the scrap mixture is crushed by a hammer-equipped rotor 16. After a period of residence in the crushing chamber 12, the crushed particles are discharged from the crushing section 10 through one of the discharge areas 14a, 14b and may be sent for further processing, for example, by conveyor belts 18a, 18b.

[0129] By controlling the movable elements 20a, 20b, it is possible to control the average residence time of the particles in the grinding chamber 12. Furthermore, the second movable element 20b can completely close the second discharge area 14b, thereby switching the operation of the grinding section 10 from a Zerdirator grinder to a shredder. [Explanation of symbols]

[0130] 10 Crushing section 12 Crushing chamber 14a, 14b discharge area 16 rotors 18a~18c Conveyor belt 20a, 20b Movable elements 22 Entrance opening

Claims

1. a) producing or providing a heterogeneous mixture of iron-containing scrap; b) crushing the heterogeneous iron-containing scrap mixture in a crushing section (10) to obtain crushed material; c) separating organic and / or inorganic impurities from the pulverized material by two or more different processes selected from the group consisting of length separation, air separation, magnetic separation, and sieving to obtain a pre-purified material; d) analyzing the pre-purified material with two or more first detection devices to detect at least two pieces of first material information, and removing components of the pre-purified material based on the first material information to obtain a purified material by analysis and removal by an automatic device; e) analyzing the purified material with one or more second detection devices to detect at least one second material signature; f) a comparison step of comparing the detected second material information with a predetermined material standard assigned to the second material information, A process for producing recycled scrap, wherein the refined material is removed as recycled scrap if the second material information satisfies the assigned predetermined material criteria.

2. and / or - detecting and analyzing spatially and / or temporally resolved profile information of the at least one first material information and / or the at least one second material information, respectively, using spatial and / or temporal resolution; and / or 2. The process of claim 1, wherein the analysis in step d) and / or step e) is performed by one or more different techniques selected from the group consisting of X-ray fluorescence analysis, optical image recognition, and infrared absorption spectroscopy.

3. The process of claim 1 , wherein the composition of the heterogeneous iron-bearing scrap mixture is controlled by the first material information and / or the second material information.

4. The grinding step in step b) is performed by The process of claim 1 , wherein the control is

5. 2. The process according to claim 1, further processing the recycled scrap further comprises detecting at least one third material information, and controlling the composition of the heterogeneous iron-bearing scrap mixture and / or the crushing step in step b) and / or the sorting step in step c) based on the at least one third material information.

6. The process of claim 1 , wherein the process is a continuous process.

7. At least one crushing unit (10) for crushing the heterogeneous iron-containing scrap mixture; a sorting means for sorting organic matter and / or metal impurities from the pulverized material; one or more first detection devices that analyze the material obtained after the sorting and detect first material information; an automatic removal means for automatically removing a fraction from the material obtained after the sorting according to the first material information; one or more second detection devices that analyze the material obtained after the removal and detect second material information; a data processing device adapted to compare the second material information with an assigned predetermined material standard, and to discharge the material refined by the device as recycle scrap if the second material information satisfies the assigned predetermined material standard; Use in the process according to claim 1. Scrap recycling plant.

8. a grinding chamber (12) having at least one discharge area of ​​the ground material, a first discharge area (14a) and a second discharge area (14b); and at least one rotor (16) equipped with a hammer, the rotor (16) being installed in the grinding chamber (12); The grinding section (10) comprises movable elements (20a, 20b) designed to control the discharge area of ​​ground material from the grinding chamber (12) available in the first discharge area (14a) and the second discharge area (14b), wherein the grinding section (10) has, at the top of the grinding chamber (12), the first discharge area (14a) and a first movable element (20a) designed to control the discharge area of ​​ground material from the grinding chamber (12) available in the first discharge area (14a), and the grinding section (10) has, at the bottom of the grinding chamber (12), a second movable element (20b) designed to control the discharge area of ​​ground material from the grinding chamber (12) available in the second discharge area (14b). Use in the process according to claim 1 or the plant according to claim 7. Grinding section (10).

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