EP1695765A1 - separation process and apparatus - Google Patents

Abstract

The method involves forming a gaseous transfer medium (6) e.g. hydrogen, by a chemical reaction of a metallic component (2) with a separation medium (5) e.g. water, or with lubricants provided in the separation medium. The transfer medium is produced in the form of gas bubbles. The rate of the formation of the transfer medium is so large that a large part of the gas bubbles adhere to a surface of the component. Independent claims are also included for the following: (1) a separation device for separating a metallic component from a mixture (2) an application of a separation device for recycling scrap metals (3) an application of a separation device for separating chips made of aluminum, magnesium or alloys of aluminum and/or magnesium.

Description

The invention relates to a process for the separation of at least one metallic component from a mixture containing them in a liquid separation medium with the aid of a gaseous transport medium for enrichment of the metallic component in the separation medium, the use of the method for the treatment and recycling of metal waste, a separation device for the separation of at least one metallic component of a mixture containing them with a separating basin for receiving a liquid separating medium in or on which at least one discharge element for separating the separated metallic component is arranged, as well as the use of the separating device.

The recycling of waste is now playing a significant role in the entire industrial world not only for ecological but for economic reasons. For example, also in the engine industry, where due to the constant attempts to keep the weight of vehicles as low as possible and thus to save fuel, more light metals are used. However, light metals as such can not usually be used directly because of their low mechanical strength, so that alloys or composites are used. Today, engine blocks are usually made of a variety of light alloys, however, due to the reduction in production costs and because of the already mentioned need to achieve the mechanical strength of these engine blocks are made of several different alloys. Usually, these alloys are cast together, so that in a subsequent machining a mixture of different metal alloys is obtained, which can not be recycled without further treatment as a secondary raw material for further processing. It is therefore necessary in advance to separate as pure as possible secondary raw materials.

DE 28 48 474 A describes a method and an apparatus for separating particulate materials, such as sand or copper grains. For this purpose, the mixture of particulate materials of different density or different specific gravity is introduced into a fluidized bed whose flow particles have an average density which is between the densities of the mixed, particulate materials. The river in the Fluidized bed is generated by an introduced gas, especially air. The apparatus used for this purpose comprises a device for discharging the separated, particulate materials, in particular a conveyor provided with projections, which dips into the fluidized bed and receives the separated particles by means of the projections.

The object of the present invention is to provide a method and a device for carrying out the method, with which at least one metallic component can be separated from a mixture. In particular, it is a partial object of the present invention to separate a mixture of chips of aluminum and magnesium or their alloys from each other.

This object is achieved independently that in the inventive method, the transport medium is formed by a chemical reaction of the metallic component or introduced into the separation medium impurities and / or the separation medium, as well as in the separation basin of the separation device according to the invention at least one distribution device for at least approximately uniform distribution of the particles of the mixture over the and / or the bottom of the separating basin is arranged. The advantage here is that the transport medium is made possible by the separation of the at least one metallic component from the rest of the mixture, within the separation medium only when needed, i. when a metallic component is introduced into the separation medium which initiates the chemical reaction, i. e. that no additional energy has to be expended in order to maintain a transport medium flow, as required by the prior art method in the form of the introduced air. According to the invention, the separation device is equipped with a distribution device for the uniform distribution of the particles in the separation basin, whereby a sufficient wetting of the at least one metallic component with the separation medium is made possible so that an increase in the efficiency of the separation can be achieved. At the same time agglomeration can be held back by this distribution device, whereby the degree of separation can be further improved, namely by preventing that other than the desired at least one metallic component is entrained by their floating in the separation medium.

The gaseous transport medium may be hydrogen resulting from the reaction of a non-noble Metal or metal alloy is formed with an aqueous phase.

It is advantageous if the gaseous transport medium produced in the form of gas bubbles, with an average bubble diameter, selected from a range with a lower limit of 0.2 mm, in particular 0.3 mm, preferably 0.35 mm, and an upper limit of 0.75 mm, in particular 0.65 mm, preferably 0.5 mm, since this allows a controlled procedure without too vigorous "foaming" within the separation medium, so that a targeted separation of the at least one metallic component, ie a targeted floating of the same, is made possible on the separation medium.

It is advantageous if the speed of the gaseous transport medium is maximally so high that at least a majority of the developed gas bubbles adhere to the surface of the metallic component, which in turn achieves or improves the separation effect by making these gas bubbles exactly the desired metallic component discharge from the mixture and no "foreign phases" from the mixture are entrained by the gas bubbles.

In addition, a short-term overcharge of the separation medium with metal ions from the reaction of the metallic component is avoided by the two preceding embodiments of the method according to the invention, so that only a long-term replacement of the separation medium is required.

Water can be used as separation medium, which on the one hand enables the already mentioned hydrogen evolution in the separation of base metals or metal alloys from the mixture and, on the other hand, an ecologically largely harmless separation medium is used.

To improve the separation effect, at least one additive can be added to the separation medium. It is advantageous if this additive adheres to the metallic component or the mixture lubricant, which in particular from the metalworking as there used cooling lubricant, so that these cooling lubricants can also be worked to a certain extent and beyond process costs are saved can, as already at the metalworking on the later separation process is taken into account when selecting the cooling lubricant.

However, adjuvants can also be added as an additive, for example those which enhance the adhesion of the gaseous transport medium to the at least one metallic component, so that the gas bubbles produced by the reaction remain at the place of their formation and thus to a very high degree exclusively the floating of the desired , cause to be separated metallic component of the mixture. For example, surfactants or adhesion aids such as e.g. Alkanesulfonates, alkane sulfates, or collectors are used.

However, it is also possible to use as additive a foaming agent or foamer, such as e.g. Polyglycols and their ethers, terpene alcohols, organic surfactants, alkylsulfonic acids, alkylbenzylsulfonic acids, silicone compounds, on the one hand the separation efficiency can be improved and on the other hand can be achieved that the separated metallic component remains floating over a longer period on the surface of the separation medium, so that the Discharge of this metallic component can be carried out batchwise.

As an additive, at least one viscosity regulator may also be used, e.g. Polyethylene glycols, diethylene glycol monoethyl ether, whereby the residence time of the at least one component within the separation medium before floating can be determined in advance, so that thus the duration of the reaction time available can be adjusted and thus the quality of the separation can be influenced.

It is advantageous if the separation is carried out at a temperature of the separation medium which is selected from a range with a lower limit of 4 ° C, in particular 40 ° C, preferably 55 ° C, and an upper limit of 180 ° C, in particular 155 ° C, preferably 135 ° C and / or if the separation is carried out under a pressure selected from a range with a lower limit of 1 mbar, in particular 2 bar, preferably 3.25 bar, and an upper limit of 10 bar, in particular 7.5 bar, preferably 5.75 bar and / or the separation is carried out at a pH of the separation medium selected from a range having a lower limit of 0, in particular 3, preferably 4.2 and an upper limit of 14, in particular 11.35, preferably 7.1, whereby a direct influence on the separation behavior is made possible, for example, on the concentration, the reaction rate and the shape of the gas bubbles. It may be advantageous if the separation medium is buffered, for example with citric acid, in order to level the pH to a certain level.

To increase the buoyancy of the separation medium, its density may be increased, e.g. by the addition of an aqueous sodium polytungstate solution and / or a zinc bromide solution. It can thus be achieved a greater security against the demolition of the gas bubbles.

The mixture may be comminuted prior to introduction into the separation medium to an average particle size with a length selected from a range with a lower limit of 6 mm, in particular 7 mm, preferably 8 mm, and an upper limit of 15 mm, in particular 12 mm, preferably 10 mm, and a width selected from a range with a lower limit of 2 mm, in particular 2.5 mm, preferably 2.75 mm, and an upper limit of 5 mm, in particular 4 mm, preferably 3 mm , and an average height which is selected from a range with a lower limit of 0.1 mm, in particular 0.15 mm, preferably 0.2 mm, and an upper limit of 0.5 mm, in particular 0.4 mm, preferably 0.3 mm, whereby a larger surface area for the reaction and thus a higher separation speed can be achieved.

Furthermore, it can be provided that the reaction is carried out with a controlled gas bubble formation, whereby a gas volume is generated, which is selected from a range with a lower limit of 0.21 / kg mixture, in particular 0.251 / kg mixture, preferably 0.3 1 / kg mixture, and an upper limit of 0.91 / kg mixture, in particular 0, 75 l / kg mixture, preferably 0.43 l / kg mixture, so preferably again only that amount of gas is generated, which for the separation of at least one metallic component is required from the mixture and thus can be prevented that other components are separated from the mixture unintentionally.

As a mixture can be used in particular one of the metalworking, for example in the form of metal shavings, these chips preferably made of aluminum and magnesium or their alloys, ie alloys of aluminum or alloys of magnesium, are used, or according to a further embodiment used as a mixture of one of metallic composite materials, it being particularly advantageous if at least one of the metals or metal alloys with a liquid medium , in particular the separation medium, reacts such that gas bubble formation occurs and thus the at least one metallic component is separated off.

Under certain circumstances, it is advantageous if the at least one metallic component of the mixture is cleaned before use, in particular degreased, so that in the event that these surface impurities, in particular fats, can not be used as an additive, a sufficient surface for the To provide reaction.

It is also advantageous if the supply of the mixture in the separation medium is carried out continuously with a conveyor, so that there is always sufficient formation of the transport medium.

It is further possible to fluidize the mixture in a fluidized bed to prevent again agglomeration within the mixture and to provide a sufficiently large surface area for the reaction.

In the separating basin, a vertical flow, in particular with the separating medium, can be generated with a predeterminable flow velocity, wherein, according to one embodiment variant, the flow velocity is just so great that the components of the mixture, in particular the metallic component, are held in suspension at least approximately completely also prevents agglomeration by uniform distribution of the mixture in the separating basin and subsequently a sufficiently large surface can be provided for the reaction.

The flow rate is advantageously adjusted as a function of the density of the separation medium and / or the mean diameter of the particles, so that at best a floating state of the particles is achieved.

According to one embodiment, the gaseous transport medium, in particular Hydrogen, collected and a recovery, for example, a thermal utilization, are supplied, whereby, for example, the necessary for the temperature of the separation medium under certain circumstances required heat energy from the process is at least partially recovered.

It is also possible that at least a volume of the separation medium is withdrawn continuously or discontinuously from the separating basin and fed to a treatment plant for the separation of metal ions contained in the separation medium, in order to be able to feed the separation medium to the renewed use and thus to a cycle within the process, and on the other hand, in some circumstances, in turn, raw materials, such as magnesium salts, such as Magnesium sulfate or magnesium chloride for further use.

According to one embodiment variant of the separating device according to the invention it is provided that the distribution device is designed as a stirrer, thereby allowing a sufficient distribution of the mixture in particular circular or oval-shaped separating basin.

However, it can also be provided that this distribution device is designed as a screw conveyor, so that the use of angular, e.g. square separating basin is just as effective as the use of round separating basins.

It is advantageous if at least two screw conveyors are arranged, each having a different conveying length in order to be able to distribute the mixture more uniformly in the separating basin.

It may also be advantageous if at least one of the screw conveyors is designed to be horizontally pivotable in order in turn to allow a more even distribution of the mixture in the separating basin.

According to a further embodiment, the distribution device may be formed as a fluidized bed in order to achieve as well as a uniform distribution of the mixture in the separating basin.

The distribution device may have a feed pipe for the vertical supply of a fluid into the separation tank in order to achieve a turbulence of the individual particles of the mixture.

Furthermore, the at least one discharge element may be a paddle roller in order to enable efficient discharge of the floated, at least one metallic component.

A shredding device can be arranged in front of the separating basin, wherein according to a variant of the shredding device at least one sieve, in particular a grading curve, can be arranged in order to have a particle size of the mixture, in particular of the at least one metallic component, with a sufficiently large surface area for rapid reaction to provide.

The at least one sieve may have an overflow, which is preferably connected to the comminution device in order to feed the oversized particles of the mixture again to the comminution device, so that the separation device can be operated at least in this area as far as possible without manual intervention.

In front of the separating basin, a cleaning step for the mixture may be arranged to remove, for example, impurities adhering to the mixture, e.g. Lubricating oils, etc., at least partially remove.

This cleaning stage may comprise at least one device for supplying a cleaning fluid, in particular a spray nozzle, whereby the cleaning itself can be designed more efficiently with little use of cleaning fluid.

It is also advantageous if a conveyor is arranged in the separating basin, with which the discharge of the other components of the mixture is made possible from the separating basin.

But it is also possible that the bottom of the separating basin at least partially bevelled in relation to a footprint of the separating basin, in particular conically formed is so that non-floating mixture components due to gravity in the lower portions of the separation sink sink, and it is according to a further embodiment of advantage, if in this area at least one discharge device, such as a slide, is arranged, with or with this other components can be removed from the separating basin.

Furthermore, the separating basin in the upper region, in particular above the separating basin, may have a gas collecting device, in particular an exhaust, in order to remove and collect the gaseous transport medium formed during the chemical reaction, in order, for example, to recover it, e.g. a thermal utilization to supply.

Finally, it is also possible that the separating basin has at least one each inlet and outlet for the separation medium in order to produce a continuous flow in the separating basin or in order to renew the separation medium or to supply it to a regeneration.

The invention further relates to the use of the method and the separation device for the recovery of metal waste, in particular a mixture of chips, aluminum and magnesium or chips of aluminum alloys and / or magnesium alloys.

For a better understanding of the invention, this will be explained in more detail with reference to the following figures.

Each shows in a schematically simplified representation:

Fig. 1

an inventive separation basin;

Fig. 2

an embodiment of the separation basin as part of an overall system.

By way of introduction, it should be noted that in the differently described embodiments, the same parts are provided with the same reference numerals or the same component names, wherein the disclosures contained in the entire description transmitted mutatis mutandis to the same parts with the same reference numerals or component names can be. Also, the position information selected in the description, such as top, bottom, side, etc. related to the immediately described and illustrated figure and are to be transferred to a new position analogous to the new situation. Furthermore, individual features or combinations of features from the different exemplary embodiments shown and described can also represent independent, inventive or inventive solutions.

1 shows a first output variant of a separating device 1 for separating at least one metallic component 2 from a mixture 3 containing same.

The separation device 1 comprises in its simplest embodiment, a separation tank 4 by a separation medium 5 is presented. The separation medium 5 is formed by a liquid, preferably water or an aqueous solution or a solvent mixture, or the like .. Instead of water but all other suitable liquids, such as organic solvents, alcohols, etc., can be used.

The inventive method for separating the at least one metallic component 2 from the mixture 3 is guided such that a transport medium 6 is formed by a chemical reaction of the metallic component 2 or with this introduced into the separation medium 5 impurities, preferably with the separation medium 5 ,

In its preferred embodiment, the process according to the invention serves to separate magnesium turnings or chips from magnesium alloys of aluminum turnings or shavings from aluminum alloys. It is therefore possible, by reaction of the magnesium with water to produce hydrogen as the transport medium 6, wherein this transport medium 6 is preferably generated in the form of gas bubbles or bubbles, which is the floating of the magnesium chips, ie the at least one metallic component 2 in the direction a surface 7 of the separation medium 5, as shown in Fig. 1, causes. Of course, the method according to the invention is also suitable for other metallic components 2, in particular base metals or alloys, which react with corresponding separation media 5, this reaction leading to the formation of gas bubbles. It is thus achieved the advantage that due to the in-situ formation of the transport medium 6 on its additional introduction into the separation medium 5, as for example takes place in known flotation, can be omitted.

The separating basin 4 is executed in its embodiment of FIG. 1 as a round separating basin. However, other cross-sections, such as oval, polygonal, e.g. square, quadrangular, etc., can be used. In the latter case, it is advantageous, since for the uniform distribution of the particles of the mixture 3 in the separation tank 4, a distribution device 8, in the case of the embodiment of FIG. 1 in the form of an agitator, is arranged, corresponding shaped distribution devices, as further below in Detail is explained to use, and thus to effect the even distribution.

By the distribution device 8, it is possible to largely avoid agglomeration within the mixture 3 and thus also a sufficient wetting of the at least one metallic component with the separation medium or a reactant contained therein, by reaction with the at least one metallic component 2, the corresponding gas formation causes to provide.

By the agitator, i. the distribution device 8, it is possible to simply pour the mixture 3 into the separating basin 4. However, it is advantageous if, during the introduction of the mixture 3 into the separating basin 4, an even distribution thereof within the separating basin 4 is taken into account, as will be explained in more detail below.

Preferably, the process is carried out such that the gas bubbles have a certain average bubble diameter selected from a range having a lower limit of 0.2 mm, in particular 0.3 mm, preferably 0.35 mm, and an upper limit of 0.75 mm , in particular 0.65 mm, preferably 0.5 mm. If gas bubbles formed too large, larger particles of the mixture 3, in particular of different particles to the intended component to be separated, could be entrained under certain circumstances, or thus mixture constituents per se, which have not yet been separated, could also float with them Efficiency of the separator 1 would deteriorate. Too small gas bubbles or gas bubbles, however, would cause insufficient buoyancy. Optionally, the gas bubbles may also have an average diameter selected from a range having a lower limit of 0.5 mm and an upper limit of 5 mm.

If one considers a magnesium chip with the dimensions l = 12 mm, b = 3.5 mm and h = 0.3 mm, the volume is increased by more than 77% with a bubble diameter of around 200 μm, provided that bubbles adhere everywhere, so that with the method according to the invention sufficient separation performance is achieved.

Further experiments on magnesium chips of the following dimensions showed the following results: Length [mm] 6 15 6 15 6 15 Width (mm] 2 2 5 5 2 5 Mean height [mm] 0.1 0.1 0.1 0.1 0.5 0.5 Bubble diameter [μm] 66 67 69 69 265 313 Volume Span [mm ³ ] 1.2 3 3 7.5 6 37.5 Volume H ₂ [mm ³ ] 0.9 2.2 2.3 5.6 4.5 27.9

About 0.047% by weight of Mg is reacted with Mg ²⁺ , whereby about 0.43 1 of H ₂ per kg of Mg is produced, so that a certain degree of safety with respect to H ₂ / Mg is achieved. Another advantage is that the amount of magnesium reacted is relatively low, so that a possible environmental impact or necessary landfill of the magnesium ionized separation medium can be kept within limits.

It was also found that the larger the bubbles are, the greater is the buoyancy with a simple occupancy of the chip surface with bubbles.

In the case of "bent" chips, it is advantageous if the method is controlled in such a way that larger and more stable bubbles form in the middle area of the chip.

It is also advantageous if the method is carried out in such a way that the gas bubbles or gas bubbles continue to grow on the particle or metal chip after their formation, so that the particle or the metal chip experiences an acceleration with respect to its or its on drive. If the particles have arrived at least in the region of the surface of the separation medium 5, it no longer interferes if the gas bubbles at least partially tear off the particle.

It should be mentioned at this point that the diameter of the gas bubbles can be adapted to the respective particle size, i. the adjustment is made by the appropriate reaction, which, however, the expert on his expertise without inventive step on the basis of representational doctrine to technical action readily choose itself accordingly.

The gas bubbles remain after their formation in an advantageous manner to those particles of the metallic component 2, where they are formed. For this purpose, it is again advantageous that these gas bubbles have a mean bubble diameter corresponding to the range described above, since too large gas bubbles tear off from the metallic particles under certain circumstances and thus do not bring about the desired buoyancy of the same.

In order to improve the adhesion of the gas bubbles to the particles of the metallic component 2, appropriate additives may be added to the separation medium 5, such as e.g. Alkanesulfonates, alkanesulfates.

In the area of the surface 7 of the separating medium 5, in the embodiment of the separating device 1 according to FIG. 1, a discharge element 9, which has the shape of a rake, is arranged. This rake is horizontally displaceable according to double arrow 10, in the direction of a discharge device 11, e.g. a chute. During this horizontal movement of the discharge element 9 already floated particles of the metallic component 2 are moved in the direction of the discharge device 11 and from the separating basin 4 subsequently via this e.g. by gravity or by appropriate conveyors, e.g. Conveyor belts, etc., removed from the system and stored in the collection in a collection, not shown, for its further use, for example, melt metallurgical use.

The residual component (s) of the mixture 3 remaining on a bottom 12 of the separating basin 4 can likewise be transported via a corresponding discharge element 9, for example once again a rake by horizontal displacement, to a further discharge device 11 and in this way removed from the system.

Instead of simple raking, it is also possible to use all of the state of the art to use this known discharge 9. So-called paddle rolls, as indicated schematically in FIG. 2, have proven to be particularly advantageous, since they allow a continuous discharge of the separated metallic component 2 from the separating basin 4 by generating a corresponding flow in the direction of the discharge device 11 ,

As already mentioned, at least one additional additive may be added to the separation medium 5. So it is e.g. it is possible to use as an additive the lubricant optionally adhering to the metallic component 2 or the mixture 3, in particular a cooling lubricant conventionally used in metal working, such as e.g. an emulsion of a synthetic and / or mineral and / or vegetable oil, in particular esterbasierend, is used. Such an addition is particularly advantageous if the transport medium 6 is formed by reaction of this additive alternatively or additionally, and if this adheres to an insufficient extent to the metallic component 2 and the mixture 3 of metal cutting machining, so that an unsatisfactory separation result would be achieved ,

It therefore proves to be advantageous to pay attention to the subsequent recycling of the resulting chips already in the metalworking, in particular in the selection of the cooling lubricant used. This is particularly advantageous when the waste chips are subjected to recycling in their own production, i. that the separating device 1 according to the invention is integrated into the production line of the respective manufacturing operation, for example engine blocks. It may therefore be possible to dispense with complex processes for the disposal of these cooling lubricants, since these are subjected to a chemical degradation process for the production of the transport medium 6 in the recycling process for recovering the metallic component 2.

As another additive, it is possible to add adjuvants to the separation medium 5 which, as already mentioned, enhance the adhesion of the gaseous transport medium 6 to the at least one metallic component 2, e.g. Alkanesulfonates, alkanesulfates.

To support the floating, ie the buoyancy, if the generation of the transport medium 6 alone is not sufficient for a complete separation, optionally a so-called foaming agent may be added to the separation medium, such as polyglycols and their ethers, terpene alcohols, organic surfactants, alkylsulfonic acids, alkylbenzylsulfonic acids, silicone compounds.

It should be mentioned at this point that to be understood by complete separation, a degree of separation of 80% to 99%, with a complete separation to 100% is not excluded.

For conditioning the separation medium 5, it is further possible to add viscosity regulators, e.g. Polyethylene glycols, diethylene glycol monoethyl ether, so as to adjust the residence time of the particles of the separated component 2 within a Aufschwimmstrecke 13, which essentially extends from the bottom 12 to the surface 7 of the separation medium 5, that is simplified about the filling level of the separation medium 5 in the separation tank 4 set. It is thus also an improved separation possible in the event that possibly unwanted components are entrained by the floating particles of the metallic component 2, since it over this residence time, i. the duration of the floating, it is possible that these undesirable components fall off from the particles towards the bottom 12.

To improve the separation performance, it is further possible that the separation medium 5 is tempered, this temperature may be selected from a range with a lower limit of 4 ° C, in particular 40 ° C, preferably 55 ° C, and an upper limit of 180 ° C, in particular 155 ° C, preferably 135 ° C. In fact, the rate of reaction, i.e. the rate of reaction, can be determined by this temperature control. the emergence of the transport medium 6 are regulated in the form of the gas bubbles, in particular when the formation of the transport medium 6 is too low at room temperature.

For this purpose, a temperature sensor 14 may be arranged in the separating basin 4, wherein this may be connected via a line 15 to a control and / or regulating device 16 in order to achieve a higher degree of automation. This control and / or regulating device 16 can be embodied, for example, in the form of a PC or the like.

In addition to the temperature, it is also possible to control the separation process over certain pressure conditions within the separation tank 4. Of course, this has to be the separating basin 4 with a cover (not shown in Fig. 1) may be provided to allow a corresponding pressure build-up. The overpressure may be selected from a range with a lower limit of 1 mbar, in particular 2 bar, preferably 3.25 bar, and an upper limit of 10 bar, in particular 7.5 bar, preferably 5.75 bar. By means of these pressure conditions, it is possible to influence the bubble diameter as well as the number of resulting bubbles of the transport medium 6. For automation, a corresponding sensor can also be arranged in the separating basin 4 for this purpose, which in turn is preferably conductively connected to the control and / or regulating device 16.

It may also be advantageous if the milieu of the separation medium 5 itself is regulated, i. in that a pH value selected from a range having a lower limit of 0, in particular 3, preferably 4.2 and an upper limit of 14, in particular 11.35, preferably 7.1, is set, for example, for the formation of the gaseous transport medium 6, whereby it is also possible to influence the kinetics of the reaction. For this purpose, a probe 17 may also be arranged in the separating basin 4, which in turn is preferably conductively connected via a line 18 to the control and regulating device 16. Optionally, it is advantageous if the separation medium 5 is buffered, e.g. with citric acid.

By choosing these measures, it is advantageously possible to align the formation of the gas bubbles of the transport medium 6 with the particular requirements of the separation process, i. that just as much gas bubbles arise in order to achieve the most complete possible floating of the component 2, for example the magnesium chips or the magnesium particles, but not so much that in addition other components of the mixture are entrained. Furthermore, these measures can also be used to influence the size of the resulting gas bubbles, which in turn allows the separation efficiency to be optimized accordingly.

It should be mentioned, however, that the specified value ranges relate in particular to the separation example aluminum shavings / magnesium shavings and that for the separation of other metallic components 2 two from a mixture 3 other parameters may be more advantageous. However, the adaptation to it again lies within the ability of the skilled person, who will do so without inventive step on the basis of the present teaching.

To achieve the mentioned separation performance, it is advantageous if per kilogram of mixture, a gas volume is generated, selected from a range with a lower limit of 0.2 1, in particular 0.25 1, preferably 0.3 1, and an upper limit of 0.9 1, in particular 0, 75 1, preferably 0.43 1.

Fig. 2 shows a variant of the inventive separation device 1, wherein like parts are provided with the same reference numerals corresponding to the embodiment of FIG. 1. Of course, individual parts of the embodiment of the separating device 1 of Fig. 1 can be transferred to this embodiment of Fig. 2, such. the temperature sensor 14, the probe 17, etc., without this having to be referenced separately in FIG.

In the event that the particles of the mixture 3 for the separation of the metallic component 2 are too large, this mixture 3, in particular the chip mixture, a feed device 19, e.g. a hopper, which is connected for example via a conveyor belt 20 or directly to a reduction device 21, abandoned. The arrangement of a conveyor belt 20 offers, for example, the advantage that the task of the mixture 3 can take place flore-side.

In the comminution device 21, for example a crusher, cutting or grinding mechanism, etc., the individual components of the mixture 3 are comminuted to the required particle size, wherein an average particle size can be selected from a range with a lower limit of 6 mm, in particular 7 mm, preferably 8 mm, and an upper limit of 15 mm, in particular 12 mm, preferably 10 mm, and a width which is selected from a range with a lower limit of 2 mm, in particular 2.5 mm, preferably 2.75 mm , and an upper limit of 5 mm, in particular 4 mm, preferably 3 mm, and an average height which is selected from a range with a lower limit of 0.1 mm, in particular 0.15 mm, preferably 0.2 mm, and an upper limit of 0.5 mm, in particular 0.4 mm, preferably 0.3 mm, so that in the separation tank 4, ie in the separation medium 5, a sufficient wetting of the metallic component 2, ie its particles for a sufficient Tren to achieve performance. The average height of the particles in the case of chip-shaped particles refers to their, viewed in cross-section, at least approximately trapezoidal appearance.

For the separation performance, it is also advantageous to use particles having a mean size between 0.1 mm and 12 mm - based on the mesh size of a screen - have.

At least one sieve (not shown in FIG. 2), in particular a sieving line, with which the desired or the desired sieve fractions are screened, can be arranged downstream of the comminuting device 21. A grading curve is always advantageous if, for the separation itself, a specific composition of different grain sizes of the mixture 3 is desired.

It is also advantageous if this at least one sieve or the uppermost sieve of the grading curve is connected to the shredding device 21 via a corresponding Rückführfordereinrichtung in the task area, for example with the feeder 19, again in this case the arrangement of the conveyor belt 20 and thus the hall level The task of the mixture 2 is advantageous because it does not require any additional energy for driving a conveyor to overcome the height of the backfraction of the grading curve or of the sieve into the inlet area of the comminuting device 21, so that this backfraction is again supplied to the comminution.

In the exemplary embodiments according to FIG. 2, the comminuting device 21 is alternatively arranged downstream of a cleaning stage 22. This cleaning stage 22 may comprise, for example, at least one spray nozzle 23, preferably several, with which a corresponding cleaning agent, e.g. a surfactant or the like. Is sprayed over the individual comminuted particles of the mixture 3 and these are thus cleaned of adhering impurities, for example by means of a solvent, so that a cleaned surface for the reaction in the separating basin 4 is available. It is advantageous if the particles of the mixture 3 are moved, for example on a perforated belt 24 or the like. Through the cleaning stage 22, so that the running cleaning agent, which is afflicted with the contaminants, run by gravity in a funnel-shaped outlet 25 and there appropriate collection, may be supplied for further processing if necessary.

At the end of the cleaning stage 22, the particles of the mixture 3 can in turn be a feed device 19, for example said hopper, another conveyor belt 20 or be passed to another conveyor, with which they are supplied to the separating basin 4. In the separating basin 4 or on this, a first distribution device 8, for example in the form of a stirrer, be arranged to best possible to separate the optionally moist particles of the mixture 3, if they were not previously subjected to drying and thus prevent agglomeration.

Subsequently, these particles can be transferred to a further conveyor 26, with which the particles of the mixture 3 are finally introduced into the separation medium 5.

This conveyor 26 is in Fig. 2 in the form of two screw conveyors, preferably with different conveying length, carried out so as to bring about the most uniform distribution of the particles of the mixture 3 through the bottom 12 of the separation tank 4. Alternatively and / or additionally, it is possible (possibly even with only one screw conveyor) that this further conveyor 26 is formed horizontally pivotable, so that wide areas of the bottom 12 of the separation tank 4 are swept by this conveyor 26 and thus a corresponding homogenization of the particles of the mixture 3 is achieved in the separation tank 4, whereby the wetting of the particles of the mixture 3 can be improved by the Trenmnedium 5.

In Fig. 2 so-called paddle rollers are shown as discharge elements 9, which generate by their rotational movement a flow in the direction of the discharge device 11 so that floated metal particles, ie, for example, magnesium turnings, fed through this flow of the discharge device 11 and are withdrawn through this system.

The bottom 12 of the separating basin 4 is conical in the embodiment according to FIG. 2, so that the downwardly sinking, non-floating particles can be fed by gravity to a slide-shaped discharge element 9 and withdrawn therefrom to the separating basin 4. Of course, other embodiments are possible here, for example, that instead of the conical design, the bottom 12 is bevelled only on one side.

2, a gas collecting device 27 is indicated by dashed lines, for example a suction hood, with the ascending gas, so for example, the hydrogen collected and fed to a corresponding collection container. As already mentioned, the hydrogen can be utilized thermally, for example, in order to obtain at least proportionately the energy required for the possibly necessary tempering of the separation medium 5.

According to another embodiment, not shown, it is possible to form the distribution device 8 for the particles of the mixture 3 in the form of a fluidized bed, so that these particles can be kept in suspension for a long time. Thus, a sufficient wetting and appropriate responsiveness are available.

It is also possible that the distribution device 8 has at least one inlet pipe for the vertical supply of a fluid in the separation tank 4, which in turn can be generated in the separation tank 4, a flow with which the particles of the mixture 3 can be held in suspension. Corresponding devices for controlling and controlling the flow velocity and generally the flow conditions in the separating basin 4 can - as they are known from the prior art - be arranged in this and be connected, for example, with previously described control and / or regulating device 16 line.

Furthermore, it is possible that the separating basin 4 has at least one inlet and one outlet for the separating medium 5, as a result of which it can be exchanged discontinuously or preferably continuously and optionally recycled, so that a content of metal ions in this separating basin 4 or separating medium 5 is achieved predeterminable level or predeterminable concentration does not exceed. The recycling of the precipitated separating medium 5 can take place, for example, in the form of a precipitation of these metal ions, for example, magnesium salts, e.g. Magnesium sulfate, magnesium chloride, etc. are precipitated and used as a secondary raw material, wherein the separation medium 5 itself can be fed to the separation tank 4 again.

The inventive method and the device according to the invention is particularly suitable for the separation of mixtures 3 from the metal processing, in particular from the metal machining, so for example, metal shavings, the described Execution "separation of aluminum shavings and magnesium shavings or their alloys" only serves as an example and the method can of course be used for similarly behaving metals or metal mixtures. For example, it is also possible in this way to separate magnesium shavings from steel alloys, ie steel shavings.

It is thus also possible to separate mixtures of which one component 2 is mixed with a corresponding liquid such as water, gas formation, e.g. Hydrogen, wherein the other component, so for example aluminum, with water or water-containing liquids cause no or little gas formation.

The gas formation can - as already mentioned - also be caused by possible, used during the manufacturing, processing and recycling process, adhering cooling lubricants, but also deliberately added by the solution additives by a chemical reaction. Due to the gas and bubble formation produced and, if appropriate, additional change in the density of the separation medium 5 with heavy solutions, such as Natriumpolywolframatlösungen, zinc bromide solutions, the separation of the at least one metallic component 2 takes place, of course, the density difference between the metallic components, e.g. of Al and Mg, plays a role.

For discharging the floated particles of the mixture 3, instead of the at least one discharge element 9, a flow, for example by supplying a corresponding fluid in the region of the surface 7 of the separating basin 4, can generally be generated.

The non-floating fraction can be withdrawn either continuously or discontinuously from the bottom 12 of the separating basin 4.

The described pretreatment in the form of the cleaning stage 22 can also be used, in addition to cleaning the chips, to neutralize the adhering cooling lubricants or, if appropriate, trigger a chemical reaction in order to accelerate the subsequent separation process, for example to destroy adhering oxide layers at least to the extent that that the corresponding gas formation can take place by chemical reaction. In this purification stage, further pretreatment may take place in such a way that over optionally added additives which adhere to the particles, in particular metal particles, of the mixture 3, a reduction in the surface tension of the separating medium 5, for example of the water, in the separating basin 4 can be achieved.

The embodiments show possible embodiments of the separation process or the Trennvorrichtung1, which should be noted at this point that the invention is not limited to the specifically illustrated embodiments thereof, but also various combinations of the individual embodiments are mutually possible and this variation possibility due to the teaching technical action by objective invention in the skill of working in this technical field expert. There are therefore also all possible embodiments, which are possible by combinations of individual details of the illustrated and described embodiment, the scope of protection.

For the sake of order, it should finally be pointed out that, for a better understanding of the structure of the separating device 1, these or their components have been shown partly unevenly and / or enlarged and / or reduced in size.

The problem underlying the independent inventive solutions can be taken from the description.

Above all, the individual in Figs. 1; 2 embodiments form the subject of independent solutions according to the invention. The relevant objects and solutions according to the invention can be found in the detailed descriptions of these figures.

S u b e c u s e c tio n a tio n s

1

separating device

2

component

3

mixture

4

separating tank

5

separation medium

6

transport medium

7

surface

8th

distribution facility

9

discharge element

10

double arrow

11

discharge

12

ground

13

Aufschwimmstrecke

14

temperature sensor

15

management

16

Control and / or regulating device

17

probe

18

management

19

feeder

20

conveyor belt

21

comminution device

22

cleaning stage

23

spray nozzle

24

perforated tape

25

outlet

26

Conveyor

27

Gas collection device

Claims (48)

Process for the separation of at least one metallic component (2) from a mixture (3) containing same in a liquid separation medium (5) with the aid of a gaseous transport medium (6) for enriching the metallic component (2) in at least one region of the separation medium (6 ), characterized in that the transport medium (6) by a reaction of the metallic component (2) or thus introduced into the separation medium (5) impurities, such as lubricant, and / or the separation medium (5) is formed. A method according to claim 1, characterized in that as gaseous transport medium (6) hydrogen is formed. A method according to claim 1 or 2, characterized in that the gaseous transport medium (6) is produced in the form of gas bubbles with a mean bubble diameter selected from a range with a lower limit of 0.2 mm, in particular 0.3 mm, preferably 0, 35 mm, and an upper limit of 0.75 mm, in particular 0.65 mm, preferably 0.5 mm. Method according to one of the preceding claims, characterized in that the speed of development of the gaseous transport medium (6) is maximally so high that at least a majority of the developed gas bubbles remain adhered to the surface of the metallic component (2). Method according to one of the preceding claims, characterized in that water is used as separation medium (5). Method according to one of the preceding claims, characterized in that the separation medium (5) additionally at least one additive is added. A method according to claim 6, characterized in that as an additive to the metallic component (2) or the mixture (3) adhering lubricant, in particular at least one used in metalworking cooling lubricant is used. A method according to claim 6 or 7, characterized in that an additive is used as an additive which enhances the adhesion of the gaseous transport medium (6) to the at least one metallic component (2), such as alkanesulfonates, alkane sulfates. Method according to one of claims 6 to 8, characterized in that the additive is a foaming agent is used, such as polyglycols and their ethers, terpene alcohols, organic surfactants, alkylsulfonic acids, alkylbenzylsulfonic acids, silicone compounds. Method according to one of claims 6 to 9, characterized in that a viscosity regulator is used as additive, such as polyethylene glycols, diethylene glycol monoethyl ether. Method according to one of the preceding claims, characterized in that the separation is carried out at a temperature of the separation medium (5) which is selected from a range having a lower limit of 4 ° C, in particular 40 ° C, preferably 55 ° C, and a upper limit of 180 ° C, especially 155 ° C, preferably 135 ° C. Method according to one of the preceding claims, characterized in that the separation is carried out under pressure which is selected from a range having a lower limit of 1 mbar, in particular 2 bar, preferably 3.25 bar, and an upper limit of 10 bar, in particular 7.5 bar, preferably 5.75 bar. Method according to one of the preceding claims, characterized in that the separation at a pH of, optionally buffered, for example, with citric acid, separation medium (5) is performed which is selected from a range having a lower limit of 0, in particular 3, preferably 4.2 and an upper limit of 14, in particular 11.35, preferably 7.1. Method according to one of the preceding claims, characterized in that an aqueous Natriumpolywolframatlösung and / or a zinc bromide solution is added to the separation medium (5). Method according to one of the preceding claims, characterized in that the mixture (3) before being introduced into the separation medium (5) is comminuted to an average particle size with a length which is selected from a range with a lower limit of 6 mm, in particular 7 mm, preferably 8 mm, and an upper limit of 15 mm, in particular 12 mm, preferably 10 mm, and a width which is selected from a range with a lower limit of 2 mm, in particular 2.5 mm, preferably 2.75 mm, and an upper limit of 5 mm, in particular 4 mm, preferably 3 mm, and an average height selected from a range with a lower limit of 0.1 mm, in particular 0.15 mm, preferably 0.2 mm , and an upper limit of 0.5 mm, in particular 0.4 mm, preferably 0.3 mm. Method according to one of the preceding claims, characterized in that the reaction is carried out with a controlled gas bubble formation, wherein a gas volume is generated, which is selected from a range with a lower limit of 0.2 l / kg mixture, in particular 0.25 l / kg mixture, preferably 0.3 l / kg mixture, and an upper limit of 0.9 l / kg mixture, in particular 0.75 l / kg mixture, preferably 0.43 l / kg mixture. Method according to one of the preceding claims, characterized in that a mixture (3) from the metalworking, in particular metal chips, is used. Method according to one of claims 1 to 16, characterized in that a mixture (3) of chips made of aluminum and magnesium or alloys of aluminum and / or magnesium is used as the mixture. Method according to one of claims 1 to 16, characterized in that as a mixture (3) metallic composite waste materials are used. Method according to one of the preceding claims, characterized in that at least the metallic component (2) of the mixture (3) is cleaned before use, in particular degreased. Method according to one of the preceding claims, characterized in that the supply of the mixture (3) into the separation medium (5) takes place continuously with a conveyor. Method according to one of the preceding claims, characterized in that the mixture (3) is fluidized in a fluidized bed. Method according to one of the preceding claims, characterized in that in a separating basin (4) a vertical flow, in particular with the separating medium (5), is generated with a predeterminable flow velocity. A method according to claim 23, characterized in that the flow rate is just so great that the components of the mixture (3), in particular the metallic component (2), at least approximately completely levitated. A method according to claim 23 or 24, characterized in that the flow rate in dependence on the density of the mixture (3) and / or the average diameter of the particles is predetermined. Method according to one of the preceding claims, characterized in that the gaseous transport medium (6), in particular the hydrogen, collected and a recovery, for example, a thermal utilization, is supplied. Method according to one of the preceding claims, characterized in that at least part of the separation medium (5) is withdrawn continuously or discontinuously from the separation tank (4) and fed to a treatment plant for the separation of metal ions contained in the separation medium (5). Use of the method according to one of the preceding claims for processing and recycling metal wastes, in particular a mixture (3) of chips of aluminum and magnesium or alloys of aluminum and / or magnesium. Separating device (1) for separating at least one metallic component (2) from a mixture (3) containing same, in particular for carrying out the method according to one of claims 1 to 26, with a separating basin (4) for receiving a liquid separating medium (5). , in or on which at least one discharge element (9) for separating the separated metallic component (2) is arranged, characterized in that in the separating basin (4) at least one distribution device (8) for at least approximately uniform distribution of the particles of the mixture ( 3) above and / or the bottom (12) of the separating basin (4) is arranged. Separating device (1) according to claim 29, characterized in that the distribution device (8) is designed as a stirrer. Separating device (1) according to claim 29, characterized in that the distribution device (8) is designed as a screw conveyor. Separating device (1) according to claim 31, characterized in that at least two screw conveyors are arranged, each having a different conveying length. Separating device (1) according to claim 31 or 32, characterized in that the or at least one of the screw conveyor is formed horizontally pivotable. Separating device (1) according to claim 29, characterized in that the distribution device (8) is designed as a fluidized bed. Separating device (1) according to claim 29, characterized in that the distribution device (8) is at least one inlet pipe for the vertical supply of a fluid in the separating basin (4). Separating device (1) according to one of claims 29 to 35, characterized in that the at least one discharge element (9) is a paddle roller. Separating device (1) according to one of claims 29 to 36, characterized in that a shredding device (21) is arranged in front of the separating basin (4). Separating device (1) according to claim 37, characterized in that the shredding device (21) is arranged downstream of at least one sieve, in particular a grading line. Separating device (1) according to claim 38, characterized in that the at least one sieve has an overflow, which is preferably connected to the comminuting device (21), are fed to the oversize particles of the mixture (3) back to the crushing device (21). Separating device (1) according to one of claims 29 to 39, characterized in that in front of the separating basin (4) at least one cleaning stage (22) is arranged for the mixture. Separating device (1) according to claim 40, characterized in that the cleaning stage (22) comprises at least one device for supplying a cleaning fluid, in particular a spray nozzle (23). Separating device (1) according to one of claims 29 to 41, characterized in that in the separating basin (4) a conveying device (28) is arranged. Separating device (1) according to one of claims 29 to 42, characterized in that the bottom (12) of the separating basin (4) at least partially beveled with respect to a contact surface of the separating basin (4), in particular conical, is formed. Separating device (1) according to claim 43, characterized in that on the contact surface adjacent the end of the chamfered bottom part a discharge device (11), in particular a slide, for a further from the mixture (3) separated component is arranged. Separating device (1) according to one of claims 29 to 44, characterized in that in an upper region of the separating basin (4), in particular above the separating basin (4), a gas collecting device, in particular a suction, is arranged. Separating device (1) according to one of claims 29 to 45, characterized in that the separating basin (4) has at least one each inlet and outlet for the separation medium (5). Use of the separating device (1) according to one of claims 29 to 46 for the recycling of metal waste. Use of the separating device (1) according to one of claims 29 to 46 for the separation of chips of aluminum and magnesium or alloys of aluminum and / or magnesium.

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