AU2019398306B2

AU2019398306B2 - Device for stressing particles by means of electric pulses

Info

Publication number: AU2019398306B2
Application number: AU2019398306A
Authority: AU
Inventors: Erik Anders; Max Hesse; Petra Hoske; Thomas Krampitz; Günter KUNZE; Holger Lieberwirth; Margarita Mezzetti; Oleg Popov; Matthias Voigt
Original assignee: Haver Eng GmbH; Bergakademie Freiberg
Current assignee: HAVER ENGINEERING GmbH; Bergakademie Freiberg
Priority date: 2018-12-10
Filing date: 2019-12-10
Publication date: 2025-02-27
Anticipated expiration: 2039-12-10
Also published as: CN113301998A; EP3894080A1; WO2020120437A1; DE102018131541B4; AU2019398306A1; EP3894080B1; CN113301998B; EP3894080C0; EA202191520A1; DE102018131541A1

Abstract

The invention relates to devices for stressing particles (9) by means of electric pulses (11) using an apparatus for supplying particles, at least one vertically arranged piece of piping (2) with a reaction space for stressing particles, and an apparatus for discharging particles. The devices are distinguished, in particular, in that they are already present in a manner better or completely separated into relatively coarse fractions for the purpose of subsequent comminution. To this end, the piece of piping (2) and therefore the reaction space is a flow duct of a flowable medium (10). Furthermore, a device (4) which conveys the medium is connected to the pipe section such that the medium flows counter to the direction of movement of particles which are fed to the piece of piping and drop through the piece of piping (2). The pipe section has at least two electrodes (5) which are arranged at a distance from one another and are connected to at least one pulse voltage generator in the form of a Marx generator (6). Furthermore, the electrodes end with or in front of the inner surface of the piece of piping , so that the electrodes (5) do not protrude into the piece of piping(2) and do not impede the flow of the medium in the piece of piping.

Description

WO 2020/120437 Al

DEVICE FOR STRESSING PARTICLES BY MEANS OF ELECTRICAL PULSES

The invention relates to devices for stressing particles by means of electrical pulses, having an apparatus for supplying particles, at least one vertically arranged pipe section with a reaction chamber for stressing particles and an apparatus for removing particles.

The principle of comminuting solids by means of electrical pulses is known. These electrical pulse methods have disadvantages particularly in the case of continuous conveying of process material consisting of solids through the reaction chamber and the different dwell times required in the reaction chamber depending on material and particle size. Furthermore, there is a risk of damage of components due to the electrical pulses that are used.

An installation for a continuous electro-hydraulic comminution and mixture of substances in a fluid medium is known from the published document FR 1 341 851 A. The electrical discharges take place due to the liquid surrounding the substance to be comminuted, generally water. Due to the plasma channel created in the liquid, a pressure wave is generated in the same, which impacts the material to be comminuted and loads the same. The generation of the electrical pulses required therefor takes place by means of LC circuits, which has the consequence of a correspondingly slow pulse rise. The liquid reservoir is pressure-surge resistant, in order to withstand the indirect stressing of the substances (pulverization) due to the shock wave generated in the water by means of electrical pulses. In the device, flat electrodes are also described, in order to maximize the effect of the shock wave. However, these project into the processing chamber or are built-in flat in a tapering pipe section. The liquid flow is impeded and the electrodes consequently experience an increased wear. A liquid flows through the reactor, in order to remove the comminution products completely upwards or downwards.

A further method for comminuting solids by means of electrical pulses is electrodynamic comminution.

A device and a method for continuously comminuting solids by means of electrical pulses is known from the published document DE 10 2014 008 989 Al. This has at least one reaction chamber, to which the solids are supplied by means of a transport medium, wherein the reaction chamber is located in a reaction vessel. This has at least one electrode set made up of at least two electrodes, which are arranged at a predetermined distance from one another and form an electrode gap in the reaction chamber. In this case, at least one central electrode and electrodes surrounding the same are present. A device for generating electrical pulses delivers the electrical pulses to the electrodes of the electrode set, wherein the solids bear so as to be pressed against the electrode set until the solids bearing there are comminuted by means of the electrical pulses in such a manner that the comminuted solids have smaller dimensions than the distance between the mutually opposite electrodes. The comminuted solids pass through the electrode gap together with the flowing transport medium. A continuous comminution is essentially only assured in the case of solids of approximately the same size. No or insufficient comminution can lead to backing up of the solids.

The published document WO 2012 129 713 A relates to an electrode arrangement for an electrodynamic fragmentation installation having a passage opening or a passage channel for material for fragmenting and having one or more electrode pairs. By stressing the material for fragmenting with high voltage pulses of the electrodes, high-voltage discharges are generated inside the passage opening or the passage channel. In this case, rod-shaped, pointed or rounded electrodes project out from the edge side of a surrounding jacket and if appropriate from a centrally arranged dome shaped insulating body into the comminution chamber, in order to obtain approximately spherical comminuted material. To this end, the electrode spacing is smaller than the maximum particle size, which can pass through the passage opening or the passage channel.

The published document JP 11-33 430 A discloses a comminution method and a device for carrying out the method. To this end, electrode plates that are inclined with respect to one another are present, between which high-voltage discharges are created by means of voltage pulses. The electrode plates form a tapering gap. To pass through the tapering gap, the particles must be smaller than the distance between the electrode plates at the respective position. A solution consisting of comminution and classification function is described. The material must therefore inevitably be comminuted in order to pass through the device.

The invention specified in Patent Claim 1 is based on the object of stressing or loading or straining particles at least in such a manner that the particles are already present better or completely broken up in relatively coarse fractions for subsequent mechanical comminution.

This object is achieved using the features specified in Patent Claim 1.

The devices for stressing or loading or straining particles by means of electrical pulses, having an apparatus for supplying particles, at least one vertically arranged pipe section with a reaction chamber for stressing particles and an apparatus for removing particles stand out in particular in that these particles are already present better or completely broken up in relatively coarse fractions for subsequent comminution.

To this end, the pipe section and therefore the reaction chamber is a flow channel of a fluid medium. Furthermore, a device conveying the medium is connected to the pipe section in such a manner that the medium flows counter to the movement direction of particles supplied to the pipe section and sinking through the pipe section. The pipe section has at least two electrodes, which are arranged spaced from one another and connected to at least one Marx generator as pulse voltage generator, wherein the pulse rise time of the Marx generator is less than 500 ns. Furthermore, the electrodes end with or before the inner surface of the pipe section, so that the electrodes do not project into the pipe section and do not impede the flow of the medium in the pipe section.

The particles passing through the pipe section are electrodynamically loaded by means of the electrical pulses, which also encloses the electrodynamic comminution of particles. In this case, the so-called Marx generator is used, which is a surge voltage generator. Using the same, pulses with a pulse rise time of less than 500 ns are generated. In the case of these short rise times, the discharge between the electrodes, which are arranged spaced from one another, preferably takes place directly through the particles or a plurality of particles simultaneously. The plasma channel created in the process leads to a direct loading of the particle. The plasma channel inside the particle is accompanied by high pressures and temperatures, which weaken or completely dissolve the bonds along the discharge channel and are reduced inside the particle. This effects a reduction of the solidity of the particle and thus also supports a selective fragmentation into different constituents. The direct energy contribution in the particles to be loaded is energy efficient and advantageously does not require a pressure-surge resistant pipe section as reaction chamber for loading particles. The pipe section can have a constant cross section over its length, so that also no influencing of the flow of the medium takes place thereby. The particles can be removed in a controlled and size selective manner. Continuous operation is easy to realize.

The voltage of the Marx generator can for example be 400 kV to 600 kV. The frequency can be equal to/greater than 25 Hz. The energy range can be greater than/equal to 7 J to equal to/less than 700 J.

The device furthermore stands out in that no movable conveying devices are required in the reaction chamber. Furthermore, the particles can also pass through the processing chamber without loading and damage or comminution associated therewith. The dwell time of the particles in the reaction chamber can advantageously be set by means of the device conveying the medium as a function of the material, the throughput and/or the size, wherein the medium flows counter to the movement direction of the particles supplied to the pipe section and falling through the pipe section. Fine particles and very fine particles that are unintentionally created can continuously be removed from the reaction chamber by means of the flowing medium counter to the falling direction of the particles to be damaged.

The electrodes do not project into the reaction chamber, so that a contact between the particles to be loaded and the electrodes and consequently an abrasive wear of the electrodes is prevented to the greatest extent. The electrodes can advantageously be controlled individually. Respective electrode pairs can be controlled simultaneously or sequentially, wherein electrode pairs can be arranged next to one another and/or below one another.

As mineral grains, the particles are therefore advantageously already present better or completely broken up in relatively coarse fractions for subsequent comminution, so that a relatively low energy outlay may be required therefor. This allows, for example, the metal containing minerals in ores to be better extracted , more completely and in higher concentrations. As a result, deposit areas with lower ore contents may still be used commercially, the completeness of deposit exploitation offered can be increased and the sustainability of the raw material preparation can be improved.

Advantageous embodiments of the invention are specified in Patent Claims 2 to 11.

The apparatus for supplying particles is optionally arranged in such a manner that the particles to be loaded sink from above downwards through the pipe section. Thus, the particles can also be supplied continuously, so that a continuous loading of particles with electrical pulses can be realized in the pipe section.

In an embodiment, a plurality of electrodes are arranged distributed around the inner circumference of the pipe section and spaced from one another. Furthermore, the electrodes are connected to pulse voltage generators.

In each case, two electrodes are optionally arranged in at least two planes of the pipe section, which are spaced from one another, wherein these electrodes are connected to the Marx generator or to Marx generators. The loading of the particles may take place in a plurality of planes during the sinking of the particles.

In a design, electrodes are arranged in a distributed manner around the inner circumference of the pipe section in one plane and/or in planes that are arranged spaced from one another. Furthermore, the electrodes are connected to the Marx generator or to Marx generators. The electrodes can therefore also be arranged helically.

The electrodes of a plane can be connected to the Marx generator or to Marx generators. Furthermore, the Marx generator is or the Marx generators are connected to a control device in such a manner that the voltages simultaneously applied at the electrodes and/or pulses of the planes differ from one another.

The apparatus for removing particles is optionally arranged in such a manner that the particles sinking through the pipe section are transported away from the device for loading particles.

In an embodiment, the device conveying the medium is connected to a control device, so that the flow rate of the medium and therefore the speed of the particles sinking through the pipe section can be influenced.

A device for removing fine and/or very fine particles is optionally arranged outside of the reaction chamber in the direction of the apparatus for supplying particles. This may be an opening in the wall of the pipe section, which can be connected to a suction apparatus.

The apparatus for supplying particles, the vertically arranged pipe section, the device conveying the medium and lines are a circuit conveying the medium.

The medium can be a gas or a liquid in particular.

An exemplary embodiment of the invention is illustrated in the drawings schematically in each case and is described in more detail in the following.

In the figures:

Fig. 1 shows a device for loading particles by means of electrical pulses, and

Fig. 2 shows a pipe section with electrodes and a reaction chamber.

A device for loading particles 9 by means of electrical pulses 11 essentially consists of an apparatus 1 for supplying particles 9, a vertically arranged pipe section 2 with a reaction chamber, an apparatus 3 for removing particles 9, an apparatus 4 conveying a medium 10, electrodes 5, a Marx generator 6 and a control device 7.

Fig. 1 shows a device for stressing or loading or straining particles 9 by means of electrical pulses 11 in a schematic illustration.

The apparatus 1 for supplying particles 9 is arranged in such a manner that the particles 9 sink from above downwards through the pipe section 2. The apparatus 3 for removing particles 9 is located such that the particles 9 sunk through the pipe section 2 are transported away from the device for loading particles 9. The device 4 conveying the medium 10 is connected to the control device 7, so that the flow rate of the medium 11 and therefore the speed of the particles 9 sinking through the pipe section 2 can be influenced. A device 8 for removing fine and/or very fine particles 9 can be arranged in the direction of the apparatus 1 for supplying particles 9.

Fig. 2 shows a pipe section 2 with electrodes 5 and a reaction chamber in a schematic illustration.

The pipe section 2 and thus the reaction chamber represents a flow channel of the fluid medium 10. To this end, the device 4 conveying the medium 10 is connected to the pipe section 2 in such a manner that the medium 10 flows counter to the movement direction of particles 9 supplied to the pipe section 2 and falling through the pipe section 2.

The pipe section 2 has the electrodes 5, which are arranged spaced from one another and connected to the Marx generator 6, wherein the electrodes 5 end with or before the inner surface of the pipe section 2, so that the electrodes 5 do not project into the pipe section 2 and do not impede the flow of the medium 10 in the pipe section 2. Electrodes 5 can also be connected to a plurality of Marx generators 6. Thus, pulses that are different from one another in terms of their frequency and/or pulse duration can also be generated. The voltage may for example be 400 kV to 600 kV. The frequency can be equal to/greater than 25 Hz in this case. The energy range can be greater than/equal to 7 J to equal to/less than 700 J in this case.

To this end, a plurality of electrodes 5 can be arranged distributed around the inner circumference of the pipe section 2 and spaced from one another. To this end, in each case, one electrode 5 may be located in at least two planes of the pipe section 2, which are arranged spaced from one another. In an embodiment, electrodes 5 can to this end also be arranged in a distributed manner around the inner circumference of the pipe section 2 in one plane and/or in planes that are arranged spaced from one another, so that the electrodes 5 are arranged in a helical shape.

At least the apparatus 1 for supplying particles, the vertically arranged pipe section 2, the device 4 conveying the medium 10 and lines may be a circuit conveying the medium 10. Building on this, the apparatus 3 for removing particles 9 can also be incorporated into this circuit.

The medium 10 is a gas or a liquid.

REFERENCE LIST

1 Apparatus for supplying particles 2 Pipe section 3 Apparatus for removing particles 4 Medium-conveying device Electrode 6 Marx generator 7 Control device 8 Device for removing fine and/or very fine particles 9 Particles Medium 11 Electrical pulse

Claims

PATENT CLAIMS

1. A device for stressing particles by means of electrical pulses, having an apparatus for supplying particles, at least one vertically arranged pipe section with a reaction chamber for stressing particles and an apparatus for removing particles, characterized in that the pipe section and thus the reaction chamber is a flow channel of a fluid medium, in that a device conveying the medium is connected to the pipe section in such a manner that the medium flows counter to the movement direction of particles supplied to the pipe section and sinking through the pipe section, in that the pipe section has at least two electrodes, which are arranged spaced from one another and connected to at least one Marx generator, wherein the pulse rise time of the Marx generator is less than 500 ns, and in that the electrodes end with or before the inner surface of the pipe section, so that the electrodes do not project into the pipe section and do not impede the flow of the medium in the pipe section.

2. The device according to Claim 1, wherein the apparatus for supplying particles is arranged in such a manner that the particles to be loaded sink from above downwards through the pipe section.

3. The device according to Claim 1, wherein a plurality of electrodes are arranged distributed around the inner circumference of the pipe section and spaced from one another and in that the electrodes are connected to the Marx generator or to Marx generators.

4. The device according to Claim 1, wherein in each case two electrodes are arranged in at least two planes of the pipe section, which are spaced from one another, and in that these electrodes are connected to the Marx generator.

5. The device according to Claim 1, wherein electrodes are arranged in a distributed manner around the inner circumference of the pipe section in one plane and/or in planes that are arranged spaced from one another and in that the electrodes are connected to the Marx generator or to Marx generators.

6. The device according to any one of Claims 1, 2 and 5, wherein the electrodes of a plane are connected to the Marx generator or to Marx generators, in that the Marx generator or the Marx generators is or are connected to a control device in such a manner that the voltages simultaneously applied at the electrodes and/or pulses of the planes differ from one another.

7. The device according to Claim 1, wherein the apparatus for removing particles is arranged such that the particles sunk through the pipe section are transported away from the device for stressing particles.

8. The device according to Claim 1, wherein the device conveying the medium is connected to a control device, so that the flow rate of the medium and therefore the speed of the particles sinking through the pipe section can be influenced.

9. The device according to Claim 1, wherein a device for removing fine and/or very fine particles is arranged outside of the reaction chamber in the direction of the apparatus for supplying particles.

10. The device according to Claim 1, wherein the apparatus for supplying particles, the vertically arranged pipe section, the device conveying the medium and lines are a circuit conveying the medium.

11. The device according to Patent Claim 1, wherein the medium is a gas or a liquid.

Fig. 1

Fig. 2