EP3325380A1

EP3325380A1 - Conveying and separating pieces of raw material

Info

Publication number: EP3325380A1
Application number: EP16753254.8A
Authority: EP
Inventors: Hans-Bernd Pillkahn
Original assignee: Proassort GmbH
Current assignee: Proassort GmbH
Priority date: 2015-07-22
Filing date: 2016-07-20
Publication date: 2018-05-30
Also published as: DE102015111890A1; WO2017013143A1

Abstract

The invention relates to a method for conveying and separating pieces of raw material which are subjected to spectroscopic composition analysis, wherein the pieces of raw material are moved onto a vibratory conveyor (1), transfer to a conveying belt (3) and are subjected to spectroscopic composition analysis, wherein the pieces of raw material are conveyed, on the vibratory conveyor (1), on one or more ramps (4) which have a gradient from the vibratory conveyor (1) to the conveying belt (3), wherein the ramps (4) are of curved design, as seen in cross section, and the pieces of raw material are conveyed over the concave sides of the ramps (4) and form one or more conveying tracks running in the conveying direction. In addition, the invention also relates to an apparatus or an installation for implementing the method according to the invention.

Description

The invention relates to a method for conveying and separating recyclable pieces of raw materials, which are subjected to a spectroscopic analysis of the composition, wherein the raw material pieces are first applied to a vibratory conveyor and separated there and then go on a conveyor belt. In times of scarce and more expensive resources, the recycling of secondary raw materials, for example in the form of scrap recycling, is of considerable economic importance. This is all the more so since large parts of the raw materials used come from third countries, which can not always guarantee security of supply. Finally, the recycling of secondary raw materials is also environmentally desirable.

The secondary raw materials are usually present as fractions, which consist of a large number of individual pieces of raw materials. In the case of new rotations from processing, the individual fractions usually originate from individual disposal points (places of origin), scrap are composed of raw materials of different and undefined origin. Even the elimination of Neuschrotten from a certain point of disposal may in turn have different chemical compositions in the individual pieces. Overall, therefore, the individual fractions are usually pre-sorted only in terms of belonging to a base material, but often differ significantly in their chemical composition in the alloy spectrum. For example, metal scrap is composed of individual parts of different alloy contents.

For the production of high-performance materials, the exact chemical composition of the target melt in the case of metallic materials is of paramount importance. Here, the economic and ecological endeavor, the highest possible proportion of secondary raw materials to the Gattierung, d. H. the Schmelzofenbesatz to obtain. A mere presorting for individual scrap groups is hardly sufficient, even for simpler commodity materials. For the production of high performance alloys (HPA), which have particular physical properties in terms of strength, wear and corrosion behavior, heat resistance, conductivity, etc., the use of secondary raw materials becomes increasingly difficult or precipitates per se. In addition, so far disturbing alloying elements are still slagged and ultimately destroyed, which in the long term is neither economically nor ecologically acceptable.

As the requirements for materials that are adjusted by macro and micro alloying are getting higher and higher, new alloys with ever finer co-ordinated alloying parts are constantly being produced. However, these alloying constituents may interfere with subsequent recycling, especially if the recycling takes place by melting in induction furnaces that do not allow metallurgical workup. For example, micro-alloying elements, which make up high-strength steel sheet materials, interfere with the indentation of spherical graphite in ferritic basic structure during high-performance iron casting.

Therefore, only portions of presorted secondary raw materials from the procurement market for the target melt are usually used. These are then blended with primary raw materials of known composition so that maximum permitted alloy contents are adjusted and, in particular, interfering alloy constituents are pressed below a specified specification limit. In terms of a functioning circular economy but the increase in the secondary raw material content would be desirable. In order to sort pieces of raw material, in particular secondary raw material pieces according to their composition, the chemical composition of the individual pieces of raw material must first be known as accurately as possible. The analysis of the piece-specific composition can in particular be achieved spectroscopically, for example with the aid of laser-induced atomic emission spectroscopy (laser-induced breakdown spectroscopy, LIBS = laser-induced breakdown spectroscopy). For analyzes of alloying elements with similar atomic masses as the base material itself, LIBS is currently the method of choice. Such alloy systems are, for example, manganese, chromium and nickel in iron or magnesium and silicon in aluminum. For the application of this method, it is of crucial importance to supply the sensor system the pieces of material in the transport direction and orthogonal to the transport direction (lateral) so isolated that in the context of the analysis, an exact assignment of the determined composition of the highest possible number of individual pieces of raw material per unit time possible is. For the spectroscopic analysis of a single piece of raw material, a defined time is available, which also depends on the demand for the accuracy of the analysis and on the state of the secondary raw material surface. The distance of the individual pieces of raw material from each other must therefore follow a defined time balance, which is described by the sensor system, the condition of the measuring objects and the measuring task itself. In addition, in the sorting of pieces of raw material before the actual spectroscopic analysis usually also time for the detection of the shape and position of the piece of raw material and the determination of suitable measurement points on the piece of raw material, an upstream ablation of the surface to expose appropriate measurement points and finally after the spectroscopic analysis needed for the computational analysis of the analysis and the supply of raw material pieces to individual sorting fractions. All these steps necessitate a precise and, according to operational experience, preselectable separation or separation of the pieces of raw material.

On the other hand, however, a high throughput of the pieces of raw material to be analyzed is necessary for a high throughput. A sufficiently high conveying speed can be achieved with the aid of conveyor belts, which according to the state of the art often travel at a speed in An order of 3 m / s work, but conveyor belts are not able to make a separation of the applied pieces. A separation in the conveying direction and laterally thereto can in principle be carried out with the aid of a vibrating conveyor. However, the conveying speed of a conventional vibratory conveyor is not sufficient for the desired high throughput with simultaneous demand for monolayer occupancy of the conveyor floor with secondary raw materials and appropriate separation. Vibratory conveyors are understood to mean, according to the invention, vibrating troughs and vibrating chutes, which differ from one another in that, in contrast to a vibrating chute, a vibrating trough also comprises a vertical component of motion.

Especially with an analysis with the help of LIBS is crucial that the pieces of raw materials must be introduced into the beam path of the laser, for measuring physical reasons, only a slight lateral deflection of the laser beam is possible. The lateral deflection should be max. +/- 150 mm, since with larger scan widths an excessive scattering of the emitted light can be observed.

For an efficient and also economically sensible analysis and sorting of Sekundärrohstoffstücken thus reliable separation of the raw material pieces in monolayer at the same time high conveying speed is necessary, combined with an avoidance of strong lateral deviations (considered in the conveying direction) of the individual pieces of raw materials.

This object is achieved according to the invention by a method for conveying and separating pieces of raw materials, which are subjected to a spectroscopic analysis of the composition, with the following steps:

- Applying and conveying the pieces of raw material on a vibrating conveyor

- Transfer of raw material pieces onto a conveyor belt spectroscopic analysis of the composition of the pieces of raw material, wherein the promotion of the pieces of raw material on the vibratory conveyor on one or more ramps, which have a slope from the vibratory conveyor to the conveyor belt, whereby the raw material pieces are accelerated, the ramps are considered arched in cross-section and the pieces of raw materials are conveyed over the concave sides of the ramps and form one or more conveying tracks running in the conveying direction.

The inventive method thus combines the advantages of a vibratory conveyor (reliable separation of raw material pieces) with those of a conveyor belt (high conveying speed). The design of the vibratory conveyor in the form of curved, a slope having ramps, has proved to be particularly advantageous insofar as the induced by the vibratory conveyor separation of raw material pieces on the conveyor is not only preserved, but due to the usually between vibratory conveyor and Conveyor belt present difference of conveyor speeds further pronounced. In addition, the curved formation of the ramps ensures that the pieces of raw material are applied to the conveyor belt within a narrow conveyor track required by the sensor system, it also being possible for several conveyor tracks to run parallel to one another in the conveying direction. In other words, the pieces of raw material within a conveyor track are arranged one behind the other in such a way that a problem-free analysis of the composition with the aid of a laser beam is possible and the laser beam does not have to undergo too large deflections. The transfer of the pieces of raw material from the vibrating conveyor onto the conveyor takes place automatically, i. The pieces of raw material slip on the conveyor due to the gradient of the ramps.

Possibly. can be arranged between the conveyor belt closest to the ramps and the conveyor belt even more suitably shaped baffles on the raw material pieces on the conveyor belt, in particular slip on the conveyor belt to decouple the raw material pieces from the vibration pulse of the vibratory conveyor and so a quiet transfer to the Ensure conveyor belt. For this purpose, the baffles in the direction Conveyor belt have a slope. The baffles may also be curved in cross-section viewed, wherein the raw material pieces pass over the concave sides of the baffles on the conveyor belt. The speed of the pieces of raw material can be further increased at the transition by appropriate inclination of the baffles. In addition, further, vertically arranged elements can be arranged on the baffles, which provide for a lateral limitation of the flow of the raw material pieces and hold the pieces of raw material in the trained conveyor tracks. Under baffles according to the invention any elements understood over which the pieces of raw material can slide on the conveyor belt, regardless of the material of the baffles. A guide plate can thus also be made of a non-metallic material.

Due to the ramps and their gradient, the pieces of raw material are generally accelerated significantly. Typical conveying speeds of conventional vibratory conveyors are on the order of 300 mm / s, of conveyor belts, however, at 3,000 mm / s; By this speed difference by a factor of 10, a strong impulse is caused in the transition of the piece of raw material from the vibrating trough on the conveyor belt, through which the piece of raw material comes into self-motion, which has a long conveying path. Especially with LIBS with pre-ablation, the piece must be very quiet on the conveyor belt. According to the invention, the raw material pieces on the ramps are preferably accelerated by a factor of 2, more preferably by a factor of 5 and even more preferably by a factor of 10. The increase in speed allows a smooth transition from the vibratory conveyor to the conveyor belt. This in turn allows the use of short conveyor belts, even at high conveying speeds, which has a positive effect on the length and capital expenditure of the system. In addition, the acceleration in the vibrating channel contributes significantly to the singling, because the gaps between the individual pieces of raw material increase.

Without the acceleration on the ramps, the pulling apart of the pieces of raw material is not possible or only to a limited extent. Especially with secondary raw materials z. B. in stamped scrap significant differences in the size of the pieces. This can easily make up a factor of 8 and more. In the case of mandatory monolayering of the pieces of raw material for analysis, it is only possible to pull them apart to a sufficient extent via appropriate speed differences. In the conveying and separating system according to the invention, an adjustable factor of typically 10 to 20 exists between the application of the pieces of raw material to the vibrating conveyor and the speed during the spectroscopic analysis process.

Vibratory conveyors are mechanical conveyors for bulk materials of different types, in which the medium to be transported is moved by means of vibrations. A typical vibratory conveyor in the form of a vibrating trough has a conveyor trough, which moves obliquely upwards in the conveying direction and back for transport, ie the movement comprises a vertical component and a horizontal component in the conveying direction. In this way, the conveyed is thrown upwards and, after the conveyor trough itself has moved back, in a lying in the conveying direction closer to the outlet end of the conveyor trough area again. The conveyed material placed on the conveyor trough at the entrance end thus gradually "jerks" towards the outlet end, always being thrown upwards somewhat by the vibrations and thrown towards the outlet end.Another form of vibrating conveyor is the shaking chute, in which, in contrast to The vibrating trough described above moves the conveyor trough only back and forth, ie only in the horizontal, but without vertical component.There is thus no "throw" of the conveyed instead, this slips with each vibration a little further in the conveying direction. At each oscillation, the conveyor trough initially moves in the conveying direction before it is accelerated in the opposite direction at the end of this movement jerky. Due to the sluggishness of the pieces of raw material, these each slide a little further in the conveying direction. The use of vibrating conveyors in which a throwing angle occurs, which is advantageously adjustable, at the beginning of the singling is also helpful insofar as loosely connected, z. B. easily hooked pieces of raw material can be separated from each other in this way. This effect is going through reinforced the inclination of the ramps. Inclination angle and throw angle add up so that the throw height of the raw material piece increases. Possibly. For example, it may be sufficient to carry out the singling only so far that only a few pieces of raw material are present together, ie it is not always necessary to make a singling in the sense that all pieces of raw material are completely separated, even if this is preferred.

Ideally, in each conveyor lane, the lateral variance of the centers of the pieces of raw material should be max. 600 mm, preferably max. 400 mm, more preferably max. 300 mm. In other words, the focal points of the laser on the pieces of raw material on which the analysis of the composition is made, within a relatively narrow, running in the conveying direction on the conveyor belt of max. 600, 400 or 300 mm width. Depending on the size of the pieces of raw material, the piece of raw material may also laterally protrude beyond the conveyor tracks, in particular if they are larger than approximately 30 cm. However, the sites where the analysis of the composition is carried out should be located within a comparatively narrow conveyor lane.

In addition, it may be useful to arrange several ramps on the vibratory conveyor one behind the other, the slope increases in the direction of the conveyor belt. In this way, the speed of the pieces of raw material from the vibratory conveyor to the conveyor belt can be specifically increased. If a plurality of ramps are arranged one behind the other, it may be sufficient if only the ramp closest to the conveyor belt is arched in order to bring about a transition to the conveyor belt in certain conveyor tracks; however, this may also apply to the other ramps.

Ideally, the pieces of raw material are accelerated in this way to a speed which corresponds to the conveying speed of the conveyor belt or at least comes close to it. In this way it is prevented that the raw material pieces by a sudden acceleration in the transition to the conveyor belt in an uncontrolled movement occur, which completely or partially repeals the ordered, previously performed separation. It is advantageous if the pieces of raw material on the ramp or ramps and possibly the baffles are accelerated to a speed that max. 50%, more preferably max. 40%, max. 30%, max. 20% or max. 10% below the conveying speed of the conveyor belt.

In some cases, however, it has also been found that the speed of the pieces of raw material during the transition to the conveyor significantly, z. B. can be increased by a factor of 2 without this having a negative impact on the stable position of the piece of raw materials. In part, the speed difference ensures a certain movement of the pieces of raw material, but after a short time they are again stable within their conveyor track on the conveyor belt. The acceleration in the transition to the conveyor belt leads to an amplification of the separation and to greater distances between the individual pieces of raw material. The acceleration can also be used to use conveyor belts with a particularly high speed, for example, with a conveying speed which are above the usual 3 m / s in the prior art. It has in fact been found that an analysis of the composition is also possible at conveying speeds of 3 m / s which are currently well above the state of the art; also conveyor speeds up to 7 m / s still allow a precise analysis of the composition and a subsequent sorting. The conveying speed of the conveyor belt can thus be 3 to 7, preferably 4 to 6, more preferably 5 to 6 m / s. However, a great advantage for the method according to the invention is a smooth running of the conveyor belt with low strip fluctuations.

The described conveying and separating method is preferably carried out in combination with laser spectroscopy, in particular laser-induced plasma spectroscopy (LIBS). Here, a very short, high-energy laser pulse is focused on the surface to be examined. The local strong heating of the material taking place there leads to the formation of a light-emitting plasma, the emission being characteristic of the respective material. This method is particularly suitable for analyzing the composition of secondary raw material pieces. At the same time, the separation and accurate recording of the individual pieces of raw material when using LIBS is particularly important because every single piece of raw material in the beam path of the laser must be introduced in order to obtain a reliable statement about the composition. In contrast, the precision necessary for the measurement in other spectroscopic methods such as X-ray spectroscopy is significantly lower, because the material to be irradiated irradiated a larger area and the emitted radiation can be detected over a larger area.

For safe detection of the individual pieces of raw material, a scan of the laser can be made, d. H. The laser beam scans different areas of the piece of raw material to be analyzed. In order to achieve a sufficiently high measurement accuracy and also to be able to determine small amounts of alloy material <500 ppm or to limit the error to this order, however, the deflection of the laser beam from the main direction must not become too large and should not be more than 150 mm. For even greater distractions there is a risk that the emitted light scatters too much and therefore incorrect measurements occur.

The spectrometer analyzes the atomic composition of the pieces of raw material. Conveniently, the analysis of the composition is followed by an automated sorting of the pieces of raw material. For this purpose, the system has a data processing device (control unit), which ensures that, depending on the composition, a piece of raw material is classified into a specific category and fed to certain fractions depending on it. For each target fraction, certain requirements can be made with respect to upper and lower limits of individual components, so that the control unit of the system can each make a decision as to whether a piece of raw material has to be assigned to a certain target fraction or to another target fraction. According to the invention, an analysis of the composition of at least a majority of the pieces of raw material and ideally each individual piece should be carried out, so that accurate sorting can be carried out even when mixing fractions of different origin.

The individual fractions can be supplied, for example, individual containers or separate conveyors, the Feed raw material pieces in turn to different uses. In this connection, it is also sensible to provide a residual fraction into which such raw material pieces are sorted, for which no further meaningful use is possible or which do not permit analysis of the composition. The sorting can be done in different, basically known from the prior art, for example pneumatically with the help of targeted air blasts, which direct the pieces of raw material in certain directions, as described in DE 100 29 951 A1. Likewise, however, purely mechanical solutions for deflecting the pieces of raw material are conceivable, for example flaps, gripping devices or the like.

In order to further increase the throughput of the plant, the raw material pieces can be applied to the conveyor belt in such a way that they form a plurality of conveyor tracks in the conveying direction, which run parallel to one another in the conveying direction. In this case, an analysis of the composition of the pieces of raw material is carried out in each conveyor lane. For this purpose, several spectroscopic devices, in particular several LIBS units must be used as a rule. When providing a plurality of conveyor tracks is of particular importance that each track remains stable in their orientation and in particular do not cross the conveyor tracks, d. H. a piece of raw material once assigned to a certain conveyor lane remains in this conveyor lane until final sorting.

In most cases it is sufficient to use a conveyor belt. The length of the conveyor belt until the spectroscopic detection is usually max. 5 to 7 m. It has been found that with the aid of the method according to the invention raw material pieces of different sizes can be conveyed and separated; the edge length of the pieces of raw material may be up to 2 m, preferably up to 1, 5 m, more preferably up to 1 m. The simultaneous sorting of pieces of raw material of an edge length of 1 m with such an edge length of only 20 cm is readily possible. However, it is also possible to increase the throughput rate downstream of the first conveyor belt to which the pieces of raw material are applied via the ramp, to arrange one or more further conveyor belts, the successively increase the conveying speed. According to the invention, the conveying speed can therefore be brought to a final conveying speed of 3 to 7 m / s, preferably 4 to 6 m / s, more preferably 5 to 6 m / s via further conveyor belts. A successive increase in the conveying speed further reduces the risk that an excessive acceleration of the pieces of raw material when hitting the ramp on the conveyor belt leads to uncontrolled movements of the pieces of raw material and thus to a cancellation of the separation.

Since the raw material pieces can have significant differences between individual sorting processes, it makes sense to make the vibratory conveyor adjustable in terms of various parameters. In particular, these can also be adjustable during operation, so that the user can optimize the parameters when applying the method to a newly sorted fraction of pieces of raw material directly so that a good separation in the conveying direction and a sorting occurs in conveyor tracks. Parameters to be set are, in particular, the oscillation amplitude, the oscillation frequency, the throw angle and the inclination of the ramps of the vibratory conveyor. The adjustability of these parameters has proven to be very advantageous because different pieces of raw materials achieve optimum delivery and separation at different delivery conditions in the vibratory conveyor. An experienced operator of the plant can immediately recognize whether the separation is proceeding in the desired manner or whether adjustments of the mentioned parameters are necessary. It is therefore advantageous if the parameters can be varied during operation, for example, from a control panel.

Typical vibration frequencies of the vibratory conveyor are in a range between 300 and 1, 200 per minute, preferably 500 to 1, 000 per minute. The throw angle with respect to the horizontal can be for example 10 to 60 °. The gradient of the ramps should preferably be in a range between 5 and 70 °, preferably in a range between 10 and 45 °

Other parameters that may be adjustable, in particular adjustable during operation, are parameters of the conveyor belt, in particular the conveying speed and possibly the shape of the conveyor belt. The shape can be tapered downwards from open at the top and flat up to an acute angle. The setting of the parameters can z. B. therefore become necessary because heavily soiled scrap more time for processing, in particular for the removal of surface layers require by ablation than Neuschrotte.

In order to adapt to the conveyed it may also be useful to provide interchangeable ramps and / or baffles. Depending on the pieces of raw material to be sorted, therefore, different ramps can be used, which differ in terms of length, gradient and / or curvature. When changing from a certain type of raw material pieces, for example, relatively small pieces of raw material with an average edge length of about 20 cm to larger pieces of raw material with an average edge length of about 80 cm can in this way the application of the raw material pieces on the conveyor belt while maintaining the Vibratory conveyor induced singling be optimized. In this context, the ramps / baffles can also be adjusted in terms of their width to the conveyed.

Possibly. For example, the ramps and / or the baffles may also be designed such that their incline can be adjusted without having to exchange the ramps / baffles. Ideally, the slope can be adjusted during operation. In this way, as well as in the setting of appropriate parameters for the vibratory conveyor or the conveyor belt, an adaptation to the concrete conveyed possible to achieve optimal separation and maintaining the separation up to the spectroscopic analysis.

In principle, the method can be applied to any piece of raw material, but as a rule it will be secondary pieces of raw material that are recycled. However, if necessary, only or predominantly primary raw material pieces may be added, in particular to produce a particular target composition. As a rule, these are meltable raw materials; ideally, they only have to are melted to obtain a target melt of the desired composition, so that an admixture of other substances or a removal of substances from the melt is no longer or at most still necessary to a very small extent to produce a new material. Secondary raw materials also distinguish between new scraps and old scraps. Scrap are those that have already been used, possibly over long periods of time, for example, car bodies to be worked up or the corresponding scissors or shredder scrap. Neuschrotte are those that arise in the manufacture of components, such as the remains of a sheet from which a certain shape was punched out. Of particular importance is the recycling of metal scrap, especially steel scrap, including particularly galvanized steel scrap, as this incurred in the automotive industry alone in a significant amount and recycling without prior sorting due to the meanwhile almost widespread use of galvanized steel would not be readily possible. In principle, however, the method according to the invention can also be used for other metal scrap, in particular aluminum, copper, zinc and titanium scrap. Also conceivable is the use in the recycling of plastic parts or glass. The method according to the invention can be used within the scope of a scrap processing, as described in DE 10 2012 015 812 A1, or within the scope of an assorting method (DE 10 2012 024 816 A1), in which target fractions of recyclable raw materials with certain desired compositions are produced. In this regard, reference is made to the aforementioned documents.

Depending on the size of the pieces of raw material, it may be useful to crush them before analysis of the composition in order to make them easier to handle. For a meaningful analysis of the composition is possible, a certain minimum size is required. Since the analysis is often carried out with the aid of a laser having a focal spot of about 50 to 400 μηπ diameter, the minimum size of the individual pieces of raw material should not be less than 2 mm, below size, the dimensions in the two dimensions of the support surface, for example a conveyor belt, to be understood, ie The piece of raw material should be at least 2 mm long and wide. Advantageously, the size applies to all dimensions including the height. It is expedient if the individual pieces of raw material are larger, for example, have a size of at least 50 mm, preferably at least 100 mm. On the other hand, the handling of large-scale, thinner pieces of raw material is difficult even in the promotion, which is why the pieces of raw material after a possible crushing step max. should have a size of 2,000 mm. Preferably, a max. Size of some 100 mm. If necessary, the comminution step can also be carried out after the step of cleaning or detaching surface coverings.

It is helpful if the pieces of raw material are at least roughly presorted with regard to their basic composition, for example with regard to the base material or the layer system, or else with regard to their size. With a known basic composition it can be decided whether a treatment of the pieces of raw material with one or more liquids for cleaning the surface and / or for detachment of surface coatings, ie a stripping is necessary before the actual method according to the invention is carried out. Here, different approaches may be useful, depending on whether it is z. B. galvanized, enamelled or provided with a plastic coating scrap or plastic remnants. For example, organic solvents such as aliphatic or aromatic hydrocarbons, chlorinated hydrocarbons, alcohols, glycol ethers, dicarboxylic acid esters, acetone, etc. can be used as paint strippers for removing organic coatings. Methylene chloride is used most frequently. To remove a zinc layer, acids or bases can be used. Corresponding methods are known to the person skilled in the art. To further increase the efficiency, the pieces of raw material to be treated can expediently be mechanically pretreated before being brought into contact with the liquid, in particular comminuted, shredded, roughened and / or otherwise deformed in order to increase the contact surfaces to the liquid. Possibly. Drying of the pieces treated with the liquid may be carried out prior to the analysis in order to remove adhering liquid residues. Since the measurement result in the spectroscopic analysis by surface coatings, enrichment or depletion of alloying elements on the surface, impurities on the surface, adhering oil layers, etc., can be distorted, it may also be useful before the actual analysis of the composition by a laser Cleaning pulses for ablation on the pieces of raw material act. With the help of the cleaning pulses coatings and impurities of the surface can be removed, so that subsequently a genuine analysis of the composition is possible. In order to increase the significance of the analysis carried out, it is also possible to analyze several locations per piece of raw material, ie, at first, an action of cleaning pulses and then an effect of analysis pulses must be performed in order to be able to determine the respective composition. The results are statistically evaluated, then sorting is performed depending on the statistically determined composition.

In order to determine the locations where a spectroscopic analysis of the composition is possible, a determination of the positions of the pieces of raw material as well as a determination of spatial information regarding the pieces of raw material can be carried out. In particular, the partial or complete determination of the shape of the pieces of raw material is understood as the determination of spatial information. This serves to prepare the analysis, in particular with regard to the determination of suitable measuring points. The position is in particular the position of the raw material piece on the transport device.

The shape, position and topography of the individual pieces of raw material can be determined by means of a laser-cutting camera / light-section sensor preceding the actual spectroscopic analysis. The shape and orientation requires reliable singulation technology as described herein. The extraction of spatial information on the pieces of raw material is also possible via a (pulsed) laser, which parallel to the transport direction a contour line of each piece of raw material over the light transit time determined. This serves to prepare the subsequent analysis process in the case of pieces of raw materials which have a considerable height difference in or from piece to piece, so that a light-optical method can focus sufficiently precisely for the actual measurement. The spatial information obtained is used to determine the places where compositional analysis takes place in the subsequent step. By determining the contour line, the cycle time of the measuring processes is increased and the measuring accuracy is increased. In addition, the influence of any relative movements of the pieces of raw material relative to the transport device is largely eliminated by measurement.

The determination of the position of the pieces of raw material is also possible with the help of a 3D scanning step, which can also serve to gain spatial information on the pieces of raw material. It is thus possible to detect the shape of the pieces of raw material. The spatial information on the pieces of raw material, in particular the shape, is automatically evaluated at which positions a spectroscopic analysis is easily possible. In this way, the analysis can be significantly accelerated, since the number of unsuccessful analysis steps is minimized. 3D scanning technologies, which are generally carried out with the aid of a laser, are well known to the person skilled in the art and are used in a variety of ways, for example for determining the shape of dental arches, for rapid prototyping etc. The WR Scott, G. Roth, ACM Computing Surveys, Vol. 35, 2003, pp. 64-96, "View Planning for Automated Three-Dimensional Object Reconstruction and Inspection".

Instead of capturing position and shape with the help of 3D scanning, other possibilities are conceivable. For example, the position of the piece of raw material in the case of metals can be determined by electromagnetic induction. For this purpose, coils may be provided, for example below the transport device, which together with a capacitor form a resonant circuit, so that the position of a metallic piece of raw material is detected electronically. Devices in which with the help of electromagnetic induction, the presence of a metallic object can be detected, are known in the art in principle.

According to an alternative embodiment, the formation of the conveyor tracks can also take place by curved guide plates, which are arranged between the vibratory conveyor and the conveyor belt, instead of curved ramps of the vibratory conveyor. Accordingly, the invention also relates to a method for conveying and separating pieces of raw material, which are subjected to a spectroscopic analysis of the composition, comprising the following steps: - applying and conveying the raw material pieces on a vibrating conveyor

- Transfer of raw material pieces to a conveyor belt and

spectroscopic analysis of the composition of the pieces of raw material, wherein the conveyance of the pieces of raw material on the vibratory conveyor on one or more ramps, which have a slope from the vibratory conveyor to the conveyor belt, between the conveyor belt closest to the ramps and the conveyor belt itself baffles are arranged, the baffles in the When viewed in cross-section, they are arched and the pieces of raw material slide over the concave sides of the guide plates onto the conveyor belt and form one or more conveying tracks running in the conveying direction. Incidentally, in this alternative embodiment, the previously said to the baffles applies.

In addition to the inventive method, the invention also relates to a device or system for carrying out a corresponding method. Accordingly, the invention relates to a device for conveying and separating pieces of raw material with a vibrating conveyor, one or more conveyor belts and means for spectroscopic analysis of the composition of the pieces of raw material, wherein on the vibratory conveyor one or more ramps are arranged, which from the vibratory conveyor to the conveyor belt have a slope and are formed curved in cross-section.

Alternatively, the invention also relates to a device for conveying and separating pieces of raw material with a vibrating conveyor, one or more conveyor belts and means for spectroscopic analysis of the composition of the pieces of raw material, wherein on the vibratory conveyor one or more ramps are arranged, which from the vibratory conveyor to the conveyor belt a gradient have guide plates are arranged between the conveyor belt closest to the ramp and the conveyor belt itself, which are considered curved in cross-section

All embodiments that are made in the context of the invention to the method apply in the same way for the devices. This applies in particular to all features described in connection with the method. The invention will be explained in more detail by way of example with reference to the attached figures. Show it:

Fig. 1 shows a system for carrying out the method according to the invention in a side view;

Fig. 2 shows a plant for carrying out the method according to the invention in the front view and

Fig. 3 shows a plant for carrying out the method according to the invention in plan view.

FIG. 1 shows a side view of a plant for carrying out the process according to the invention. The raw material pieces are first filled into a bunker 7 serving as a storage container, from which they pass over to the vibrating conveyor 1. To the movement of Raw material pieces from the bunker 7 to bring about the actual vibratory conveyor 1, the bottom of the bunker 7 itself may be formed as a vibratory conveyor 1. The vibratory conveyor 1 has at least one ramp 4 with a slope, whereby the raw material pieces are significantly accelerated during the promotion. Below the vibrating conveyor 1, the oscillating drive 2 is mounted, whose parameters (frequency, throw angle and throw amplitude) are adjustable. By not visible in this illustration curvature of the ramps 4 ensures that the raw material pieces form conveyor tracks 5. When transferring the pieces of raw material from the vibratory conveyor 1 on the conveyor belt 3, the conveyor tracks are maintained.

FIG. 2 shows a system for carrying out the method according to the invention in a frontal view, wherein in particular the ramps 4 are shown in cross-section. In the embodiment chosen here, two ramps 4 are arranged parallel to one another. Both ramps 4 have a curvature, so that two conveyor tracks 5 form.

FIG. 3 shows the plant in a plan view. The raw material pieces are transferred from the bunker 7 to the vibrating conveyor 1, wherein the vibrating conveyor 1 in this case has two ramps 4, which provide for the formation of two conveyor tracks 5. The transition to the conveyor belt 3 via itself to the vibratory conveyor 1 subsequent baffles 6, which have a greater slope than the ramps 4 of the vibratory conveyor, wherein on the baffles 6 additional lateral plates 8 are arranged, which ensure that the raw material pieces in the Transition to the conveyor belt 3 in their conveyor lane 5 remain.

Claims

claims

1. A method for conveying and separating pieces of material, which are subjected to a spectroscopic analysis of the composition, comprising the following steps:

Applying and conveying the raw material pieces on a vibrating conveyor (1)

- Transfer of raw material pieces to a conveyor belt (3) and

- Spectroscopic analysis of the composition of the pieces of raw material, characterized in that the promotion of the pieces of raw material on the vibratory conveyor (1) on one or more ramps (4), which from the vibratory conveyor (1) to the conveyor belt (3) have a slope and viewed in cross section are formed arched, the raw material pieces on the concave sides of the ramps (4) are promoted and one or more extending in the conveying direction conveying tracks (5) form.

2. The method according to claim 1, characterized in that on the vibratory conveyor (1) a plurality of ramps (4) are arranged one behind the other, wherein the gradient in the direction of the conveyor belt (3) increases.

3. The method according to claim 1 or 2, characterized in that between the conveyor belt (3) next coming ramps (4) and the conveyor belt (3) itself baffles (6) may be arranged over which slide the pieces of raw material on the conveyor belt (3) ,

4. The method according to claim 3, characterized in that the

Guide plates (6) viewed in cross-section are curved and the pieces of raw material on the concave sides of the baffles (6) on the conveyor belt (3) slip.

5. The method according to any one of claims 1 to 4, characterized in that the raw material pieces on the ramps (4) and

Baffles (6) are accelerated to a speed that max. 50%, more preferably max. 40%, max. 30%, max. 20% or max. 10% below the conveying speed of the conveyor belt (3).

6. The method according to any one of claims 1 to 5, characterized in that the analysis of the composition of the pieces of raw material by means of laser-induced plasma spectroscopy (LIBS) takes place.

7. The method according to any one of claims 1 to 6, characterized in that an automatic sorting of the raw material pieces takes place in dependence on the determined composition.

8. The method according to any one of claims 1 to 7, characterized in that the pieces of raw material are applied to the conveyor belt (3) in such a way that in each conveyor track (5) the lateral variance of the centers of the pieces of raw material max. 600 mm, preferably max. 400 mm, more preferably max. 300 mm.

9. The method according to any one of claims 1 to 8, characterized in that after the first conveyor belt (3) one or more further conveyor belts (3) are arranged, on which the conveying speed is further increased.

10. The method according to any one of claims 1 to 9, characterized in that the conveyor belt (3) or one of the conveyor belts (3) has a conveying speed of 3 - 7 m / s, preferably 4 - 6 m / s, more preferably 5 - 6 m / s reached.

1 1. Method according to one of claims 1 to 10, characterized in that the vibrating conveyor (1) is adjustable in terms of vibration amplitude, vibration frequency, throw angle and / or inclination.

12. The method according to any one of claims 1 to 1 1, characterized in that the ramps (4) are interchangeable.

13 Processes for conveying and separating pieces of material, which are subjected to a spectroscopic analysis of the composition, with the following steps:

Applying and conveying the raw material pieces on a vibrating conveyor (1)

- Transfer of raw material pieces to a conveyor belt (3) and

spectroscopic analysis of the composition of the pieces of raw material, characterized in that the conveyance of the pieces of raw material on the vibrating conveyor (1) takes place on one or more ramps (4) having a slope from the vibrating conveyor (1) to the conveyor (3), wherein between the The conveyor belt (3) nearest ramps (4) and the conveyor belt (3) itself baffles (6) are arranged, the baffles (6) viewed in cross-section curved and the raw material pieces on the concave sides of the guide plates (6) on the conveyor belt (3) slip and form one or more conveying tracks (5) running in the conveying direction.

14. An apparatus for conveying and separating pieces of raw material with a vibrating conveyor (1), one or more conveyor belts (3) and means for spectroscopic analysis of the composition of the pieces of raw material, characterized in that on the vibrating conveyor (1) one or more ramps (4) are arranged, which from the vibratory conveyor (1) to the conveyor belt (3) have a slope and which are formed curved in cross-section.

15. An apparatus for conveying and separating pieces of raw material with a vibratory conveyor (1), one or more conveyor belts (3) and means for spectroscopic analysis of the composition of the pieces of raw material, characterized in that on the vibratory conveyor (1) one or more ramps (4) are arranged, which from the vibratory conveyor (1) to the conveyor belt (3) have a slope, between the conveyor belt (3) next approaching ramps (4) and the conveyor belt (3) itself baffles (6) are arranged, which arched viewed in cross section are formed.