EP3261768B1 - Method and device for fragmenting and/or weakening pourable material by means of high-voltage discharge - Google Patents

Description

TECHNICAL AREA

The invention relates to methods for fragmentation and / or weakening of pourable material by means of high-voltage discharges and devices for carrying out the method according to the preambles of the independent claims.

STATE OF THE ART

It is known from the prior art to comminute or weaken various materials by means of pulsed high-voltage discharges in such a way that they can be comminuted more easily in a downstream mechanical comminution process.

For the fragmentation and / or weakening of pourable material by means of high-voltage discharges, basically two different types of process are known today.

For small quantities of material or strict specifications regarding the purity and / or the target particle size of the processed material, the fragmentation and / or weakening of the material takes place in batch mode in a closed process vessel in which high-voltage breakdowns are generated by the material.

In the case of large amounts of material, the fragmentation and / or weakening of the material takes place in a continuous process, by passing a stream of material from the material to be shredded past one or more high-voltage electrodes and generating these high-voltage breakdowns through the material. Such a process is from the document DE 197 27 534 A1 known.

However, this results in the problem that in a compared to the actual process zone in which the high voltage breakdowns take place, too broad material flow is not the entire material is processed, which affects the quality of the processed product, while on the other hand at a too narrow material flow part of the high voltage breakdowns to the lateral boundary walls of the material flow leading device takes place, which reduces the process efficiency and destroys these boundary walls over time. This also reduces the life of the plant and there is a risk of contamination of the processed material with foreign material.

PRESENTATION OF THE INVENTION

It is therefore an object to provide continuous methods and apparatus for fragmenting and / or weakening pourable material by means of high-voltage discharges, which do not have the aforementioned disadvantages of the prior art or at least partially avoided.

This object is solved by the subject matters of the independent claims.

According to these, a first aspect of the invention relates to a method for fragmenting and / or weakening pourable material, in particular rock fragments or crushed rock, by means of high-voltage discharges.

In this case, a flow of material from the pourable material to be fragmented or weakened immersed in a process liquid at a high voltage electrode assembly with one or more high voltage electrodes is passed while high voltage breakdowns are generated by the material of the material flow by applying the high voltage electrodes with high voltage pulses. According to the invention is doing the zone of the flow of material in which the high voltage breakdowns are generated by the material, as seen in the advancing direction laterally of substantially immobile areas or zones of the same material limited (stationary material areas).

In this way, the lateral boundaries of the zone of the moving material stream in which the high-voltage breakdowns take place (process zone) are formed by identical but essentially non-moving material, which makes it possible to dispense with means for lateral limitation of the actual process zone, and contamination with foreign material is prevented.

Advantageously, the stationary material areas are formed by the material supplied via the material flow. For this purpose, the stationary material regions are preferably formed such that the edge regions of the material stream are dammed at a location downstream of the high-voltage electrode arrangement, so that immobile material zones extend laterally along the entire length of the process zone.

Further, it is preferable that the moving material stream and the still material areas are formed by providing the pourable material in a process liquid flooded gutter-type device whose bottom is formed in a central area of a conveyor belt or a conveyor chain and in FIG is fixed to the edge areas. In this way, the stationary material areas can be generated in a controlled and low-wear manner.

Any material that is carried away from the material flow from the still material areas is preferably replaced by material from the flow of material and / or replaced by separately supplied material. Depending on the structure of the system used to carry out the process, one or the other Variant be particularly advantageous or even a combination thereof.

A second aspect of the invention relates to a further method for fragmenting and / or weakening pourable material, in particular rock fragments or crushed rock, by means of high-voltage discharges.

In this case, a flow of material from the pourable material to be fragmented or weakened immersed in a process liquid is passed to a high-voltage electrode arrangement with one or more high voltage electrodes, while high voltage breakdowns are generated by the material of the material flow by applying the high voltage electrodes with high voltage pulses. According to the invention, the middle region of the material flow is subjected to high-voltage breakdowns, while the edge regions of the material flow remain essentially unaffected by high-voltage breakdowns. Subsequently, the high-voltage breakdown material of the middle region of the material flow downstream of the high-voltage electrode arrangement is separated from the untreated material of the edge regions of the material flow. In this method, the zone of the material flow in which the high-voltage breakdowns take place (process zone), laterally limited by material flow of the material, which is not treated with high voltage breakdowns, which also has the advantage that on-site facilities for lateral limitation of the actual process zone can be dispensed with and contamination with foreign material is prevented.

It is preferred that the untreated material separated from the treated material from the middle region of the material flow of the edge regions of the material flow wholly or partially at a location upstream of the high voltage electrode assembly is fed back into the material flow, with advantage in the middle region of the material flow. In this way, the proportion of untreated material, ie material that is not treated with high voltage breakdowns, can be minimized.

In the methods according to the first and second aspects of the invention, the high-voltage electrode arrangement advantageously comprises a matrix of a plurality of high-voltage electrodes, which are each subjected to high-voltage pulses during normal operation. As a result, it is possible to achieve a two-dimensional loading of the bypassed material flow with high-voltage breakdowns.

In this case, each of the high-voltage electrodes of the matrix preferably has its own high-voltage generator, with which it is subjected to high-voltage pulses independently of the other high-voltage electrodes. This makes it possible to ensure a uniform and high energy input into the material flow over the entire surface of the matrix or to selectively apply individual areas with different amounts of energy.

As a counterelectrode for the high voltage electrodes of the high voltage electrode arrangement, according to a preferred embodiment of the method according to the first and the second aspect of the invention, an element limiting the underside of the material flow in the region of the high voltage electrode arrangement is used, so that by applying the high voltage electrodes with high voltage pulses high voltage breakdowns between the respective high voltage electrode and this element take place through the material flow. Preferably, this element is formed by a conveyor belt or a conveyor chain, with which or which of the material flow is guided past the high-voltage electrode arrangement. In this case, the high-voltage electrodes of the high-voltage electrode arrangement are preferably immersed in the material flow. With this process variant can be acted particularly intensively on the material of the material flow, since the high voltage breakdowns are made over the entire thickness of the material flow.

In another preferred embodiment of the methods according to the first and second aspects of the invention, each of the high voltage electrodes of the high voltage electrode assembly has one or more of its own, i. the respective high voltage electrode exclusively associated, counterelectrodes, which is so arranged laterally next to and / or below this high voltage electrode, that by applying the respective high voltage electrode with high voltage pulses Hochspannungsdurchschläge between the high voltage electrode and the or the counter electrodes through the passing past these material flow be generated. Preferably, the high voltage electrodes and / or the counter electrodes are immersed in the material flow.

This results in the advantage that the breakdown voltage is substantially decoupled from the thickness of the material flow, so that material flows from large pieces of material can be processed without further ado. Another advantage of this embodiment is that it provides the greatest possible freedom of design with regard to the support surface or the conveyor for the material flow in the region of the process zone offers because the bottom surface of the process zone is not needed as a counter electrode.

It is further preferred in the last-mentioned preferred embodiment that the counterelectrodes are carried by the respective high-voltage electrode or by its supporting structure.

As explained above, it is possible with the method according to the invention to fragment and / or weaken pourable material in a continuous process by means of high-voltage discharges in a low-wear and low-contamination manner.

A third and a fourth aspect of the invention relate to an apparatus for carrying out the method according to the first aspect or the second aspect of the invention.

The device comprises a high-voltage electrode arrangement with one or more high-voltage electrodes and one or more high-voltage generators, by means of which or which the high-voltage electrode or the high-voltage electrodes of the high-voltage electrode arrangement can be acted upon by high-voltage pulses.

Further, the apparatus comprises a conveying means, preferably conveying in a straight line, e.g. in the form of a conveyor belt or a conveyor chain, which is arranged in a tank filled or filled with a process liquid and with which in normal operation a stream of material from a free-flowing fragmented and / or weakened material are immersed in the process liquid passed to the high voltage electrode assembly can be generated while high voltage breakdowns by the material flow as a result of application of high voltage pulses to the high voltage electrode assembly.

In this case, the device according to the third aspect of the invention is designed such that during normal operation when passing the material flow in the lateral regions of the zone in which the high-voltage breakdowns are produced by the material of the material flow, the material flow material in each case accumulates to a substantially stationary material zone, which is substantially unaffected by the high-voltage breakdowns. Advantageously, the device has facilities for targeted damming of the material flow, eg baffles or lateral boundary walls for the material flow with depressions in which the material accumulates. Due to the fact that the lateral boundaries of the zone of the moving material flow in which the high-voltage breakdowns take place (process zone) are formed by identical but substantially immobile material, it is possible to dispense with wear-intensive devices for lateral limitation of the actual process zone, which has a positive effect on the operating costs and affects the maintenance-related downtime of the device and also allows a process management with low foreign material contamination.

The device according to the fourth aspect of the invention is in contrast to the device according to the third aspect of the invention designed such that in normal operation when passing the material flow to the high voltage electrode assembly, the middle portion of the material flow is subjected to high voltage breakdowns, while the edge regions of Material flow are substantially unaffected by the high voltage breakdowns. In addition, the device has a separation device, by means of which in the normal operation downstream of the high-voltage electrode arrangement, the material of the edge regions of the material flow is separated from the material of the central region of the material flow. Advantageously, the device further comprises additional means for returning the separated with the separation device material of the edge regions of the material flow back into the flow of material upstream of the high voltage electrode assembly so that this material can be redirected past the high voltage electrode assembly for fragmentation and / or weakening thereof or for reformation of the edge regions of the material stream.

Because the lateral boundaries of the zone of the moving material flow in which the high-voltage breakdowns take place (process zone) are formed by the material of the moving material flow, wear-intensive devices for lateral delimitation of the actual process zone can also be dispensed with, which, as already described has been mentioned, has a positive effect on the operating costs and the maintenance-related downtime of the device and also allows a process management with low foreign material contamination.

BRIEF DESCRIPTION OF THE DRAWINGS

• Fig. 1 einen Längsschnitt entlang der Linie B-B in Fig. 3 durch eine erste erfindungsgemässe Vorrichtung;
• Fig. 2 eine Draufsicht von oben auf die Vorrichtung aus Fig. 1;
• Fig. 3 einen Querschnitt durch die Vorrichtung entlang der Linie A-A in Fig. 1;
• Fig. 4 einen Längsschnitt entlang der Linie D-D in Fig. 6 durch eine zweite erfindungsgemässe Vorrichtung;
• Fig. 5 eine Draufsicht von oben auf die Vorrichtung aus Fig. 4;
• Fig. 6 einen Querschnitt durch die Vorrichtung entlang der Linie C-C in Fig. 4;
• Fig. 7 eine Seitenansicht einer der Hochspannungselektroden der Vorrichtungen;
• Fig. 8 eine Seitenansicht einer ersten Variante der Hochspannungselektrode aus Fig. 7; und
• Fig. 9 eine Seitenansicht einer zweiten Variante der Hochspannungselektrode aus Fig. 7.

Further embodiments, advantages and applications of the invention will become apparent from the dependent claims and from the following description with reference to FIGS. Showing:

• Fig. 1 a longitudinal section along the line BB in Fig. 3 by a first device according to the invention;
• Fig. 2 a top view of the device from above Fig. 1 ;
• Fig. 3 a cross section through the device along the line AA in Fig. 1 ;
• Fig. 4 a longitudinal section along the line DD in Fig. 6 by a second device according to the invention;
• Fig. 5 a top view of the device from above Fig. 4 ;
• Fig. 6 a cross section through the device along the line CC in Fig. 4 ;
• Fig. 7 a side view of one of the high voltage electrodes of the devices;
• Fig. 8 a side view of a first variant of the high voltage electrode Fig. 7 ; and
• Fig. 9 a side view of a second variant of the high voltage electrode Fig. 7 ,

WAYS FOR CARRYING OUT THE INVENTION

The FIGS. 1 to 3 show a first inventive device for fragmenting pourable material 1 by means of high voltage discharges, once in a longitudinal section along the line BB in Fig. 3 ( Fig. 1 ), once in a plan view from above ( Fig. 2 ) and once in a cross section along the line AA in Fig. 1 ( Fig. 3 ).

As can be seen, the device has a high-voltage electrode arrangement 2 with a matrix of 16 high-voltage electrodes 7, which are arranged in four consecutively arranged rows each with four high-voltage electrodes 7 in the direction of passage through the material S (in the figures, for the sake of clarity, only one each the high-voltage electrodes with the reference numeral 7).

The high voltage electrodes 7 are shown in the intended operation with one each applied directly above them high voltage generator 3 with high voltage pulses.

Below the high-voltage electrode arrangement 2, arranged in a tank 5 flooded with water 4 (process liquid), there is a conveyor belt 6, by means of which a flow of material from a pourable material 1 to be fragmented, in the present case fragments of noble metal ore, from the feed side A of the device forth in the material passage direction S is passed to the high voltage electrodes 7 of the high voltage electrode assembly 2, while high voltage breakdowns are generated by the material 1 as a result of application of high voltage pulses to the high voltage electrode assembly 2. In this case, the material 1 of the material flow is immersed in the water 4 located in the basin 5, as well as the high-voltage electrodes 7 arranged above it.

The height of the flow of material is adjusted prior to entry into the area between the conveyor belt 6 and the high voltage electrode assembly 2 (process zone) through a passage restriction plate 12.

How out Fig. 3 can be seen, the conveyor belt 6 seen in the direction of passage S does not extend over the entire width of the basin 5, but in the region of the basin center across the width of the process zone in which the high voltage breakdowns are carried out by the flow of material. Along the edge regions of the basin 5 extending at the top of the conveyor belt 6 fixed to the side wall of the basin 5 connected support sections 13, at the ends downstream of the high voltage electrode assembly 2 baffles 10 are arranged, which cause the material 1 in the edge regions of the pelvis 5 is dammed up on the support portions 13 and thereby forms substantially immobile material zones 9 along these edge regions, which the process zone in which the high-voltage breakdowns be generated by the material 1 of the material flow, limit laterally.

As in particular from the FIGS. 1 and 3 can be seen, the transported on the conveyor belt 6 material 1 is increasingly fragmented when passing through the process zone, while the still material 1 in the edge regions 9 of the basin 5 remains virtually unchanged.

Downstream of the high-voltage electrode assembly 2, the fragmented material 1 emerging from the process zone is discharged from the conveyor belt 6 into a collection funnel 14 at the end of the basin 5, from where it is conveyed out of the basin 5 with a conveyor (not shown).

The FIGS. 4 to 6 show a second inventive device for fragmenting pourable material 1 by means of high-voltage discharges, once in a longitudinal section along the line DD in Fig. 6 ( Fig. 4 ), once in a plan view from above ( Fig. 5 ) and once in a cross section along the line CC in Fig. 4 ( Fig. 6 ).

This device is different from the one in the FIGS. 1 to 3 shown device that here the conveyor belt 6 seen in the direction of passage S extends over the entire width of the basin 5, so that the moving material flow covers the entire width of the basin 5.

As in particular from the FIGS. 4 and 6 can be seen, the middle portion of the material flow is applied when passing through the process zone with high voltage breakdowns, which leads to an increasing fragmentation of the material 1 in this area, while the edge regions of the material flow remain virtually untouched by high voltage breakdowns, so that the material 1 guided there original piece remains.

Downstream of the high-voltage electrode arrangement 2, the material flow emerging from the process zone is discharged from the conveyor belt 6 into three collection funnels 14, 14a, 14b separated by separation walls 11 and extending side by side over the entire width of the conveyor belt 6 at the end of the basin 5. In this case, the separation walls 11 are arranged such that the fragmented material 1 is discharged from the central region of the material flow into the central collecting funnel 14, while the unfragmented material 1 is discharged from the edge regions of the material flow into the outer collecting funnels 14a, 14b.

The fragmented material 1, which is discharged into the central collecting funnel 14, is conveyed out of the basin 5 by means of a conveying device (not shown) and supplied for further use. The non-fragmented material 1, which is discharged into the outer collecting funnels 14a, 14b, is conveyed out of the basin 5 by means of conveying devices (not shown) and returned to the material flow on the feeding side A of the device.

How out Fig. 7 which shows one of the high voltage electrodes 7 of the high voltage electrode assemblies 2 of the devices in side view, each of the high voltage electrodes 7 has its own grounding counter electrode 8, which is disposed laterally adjacent to the respective high voltage electrode 7, in the illustrated operation the application of high-voltage pulses to the respective high-voltage electrode 7 generates high-voltage breakdowns between the high-voltage electrode 7 and its associated counter-electrode 8 through the material 1 of the material flow. In this case, the counter electrode 8 is attached to the support structure of the high-voltage electrode 7.

The FIGS. 8 and 9 show side views of two variants of the high voltage electrode Fig. 7 ,

Fig. 8 shows a high voltage electrode 7, which differs from the in Fig. 7 shown essentially differs in that it has two identical, mirror image opposite counter-electrodes 8. Another difference is that this high voltage electrode 7 has a straight electrode tip.

Fig. 9 shows a high voltage electrode 7, which differs from the in Fig. 8 shown essentially differs in that here the in Fig. 8 shown two mirror-inverted counter-electrodes 8 are connected below the high voltage electrode 7 to a single, U-shaped counter electrode 8.

During normal operation, the high voltage electrodes 7 and the counter electrodes 8 are preferably immersed in the material flow.

While preferred embodiments of the invention are described in the present application, it should be clearly understood that the invention is not limited to these and may be practiced otherwise within the scope of the following claims.

Claims (15)

1. Method for fragmenting and/or weakening of pourable material (1) by means of high-voltage discharges, comprising the steps of:

   a) providing a high-voltage electrode assembly (2), which is assigned to a high-voltage generator (3) by means of which it is chargeable with high-voltage pulses;

   b) guiding of a material flow of pourable material (1), immersed in a process liquid (4), past the high-voltage electrode assembly (2); and

   c) producing of high-voltage punctures through the material flow during the guiding thereof past the high-voltage electrode assembly (2) by means of charging of the high-voltage electrode assembly (2) with high-voltage pulses,

   characterized in that the zone of the material flow in which high-voltage punctures through the material (1) of the material flow are produced as viewed in a guiding-past direction (S) is laterally delimited by substantially unmoved zones (9) of the same material (1).
2. Method according to claim 1, wherein the substantially unmoved zones (9) are produced in that the boundary zones of the material flow are piled up downstream of the high-voltage electrode assembly (2).
3. Method according to one of the preceding claims, wherein the material flow and the substantially unmoved zones (9) are produced in that the material (1) is provided in a trough-like or tank-like device (5), the bottom of which is formed in a central zone by a conveyor belt (6) or a conveyor chain and is fixed in the boundary zones.
4. Method according to one of the preceding claims, wherein material (1) which is carried away from the material flow from the substantially unmoved zones (9), is replaced by material (1) from the material flow.
5. Method according to one of the preceding claims, wherein material (1) which is carried away from the material flow from the substantially unmoved zones (9), is replaced by separately supplied material.
6. Method for fragmenting and/or weakening of pourable material (1) by means of high-voltage discharges, comprising the steps of:

   a) providing a high-voltage electrode assembly (2) which is assigned to a high-voltage generator (3) by means of which it is chargeable with high-voltage pulses;

   b) guiding of a material flow of pourable material (1), immersed in a process liquid (4), past the high-voltage electrode assembly (2); and

   c) producing of high-voltage punctures through the material flow during the guiding thereof past the high-voltage electrode assembly (2) by means of charging of the high-voltage electrode assembly (2) with high-voltage pulses,

   characterized in that the high-voltage punctures are produced in such a way that the central zone of the material flow is charged with high-voltage punctures while the boundary zones of the material flow remain unaffected by high-voltage punctures, and wherein the material (1) of the central zone of the material flow is separated from the material (1) of the boundary zones downstream of the high-voltage electrode assembly (2) after the charging with high-voltage punctures.
7. Method according to claim 6, wherein the material (1) from the boundary zones which is separated from the material (1) from the central zones is fed back into the material flow completely or partially upstream of the high-voltage electrode assembly (2), in particular into the central zone of the material flow.
8. Method according to one of the preceding claims, wherein the high-voltage electrode assembly (2) comprises a matrix of several high-voltage electrodes (7), each of which are charged with high-voltage pulses.
9. Method according to claim 8, wherein a specific high-voltage generator is assigned to each high-voltage electrode, with which it is charged with high-voltage pulses independently of the other high-voltage electrodes.
10. Method according to one of the preceding claims, wherein as a counter-electrode for the high-voltage electrodes of the high-voltage electrode assembly an element delimiting the bottom side of the material flow in the region of the high-voltage electrode assembly is used, and in particular, wherein this element is a conveyor belt or a conveyor chain, with which the material flow is guided past the high-voltage electrode assembly.
11. Method according to one of the claims 1 to 9, wherein each of the high-voltage electrodes (7) of the high-voltage electrode assembly (2) has at least one specific counter-electrode (8) which is arranged laterally beside and/or below it in such a way that by means of charging of the respective high-voltage electrode (7) with high-voltage pulses, high-voltage punctures between the high-voltage electrode (7) and the counter-electrode (8) through the material flow guided past these are produced.
12. Device for carrying out the method according to claim 1, comprising:

    a) a high-voltage electrode assembly (2), which is assigned to a high-voltage generator (3), with which it is chargeable with high-voltage pulses; and

    b) a conveying device (6), in particular in the form of a conveyor belt (6) or a conveyor chain, arranged in a basin (5) which is filled or fillable with a process liquid (4), with which in the intended operation a material flow of a pourable, to be fragmented and/or weakened material (1), immersed in a process liquid (4), can be guided past the high-voltage electrode assembly (2) while high-voltage punctures through the material flow are produced by means of charging of the high-voltage electrode assembly (2) with high-voltage pulses,

    characterized in that the device is structured such that, in the intended operation, during the guiding past of the material flow, in the lateral zones of the zone in which the high-voltage punctures through the material (1) of the material flow are produced, the material (1) of the material flow each is piled up to a substantially unmoved material zone (9), which is essentially unaffected by the high-voltage punctures.
13. Device according to claim 12, wherein the device comprises damming devices, in particular baffles (10), or lateral delimiting walls for the material flow with recesses therein, for piling up of the material flow to the substantially unmoved material zones (9).
14. Device for carrying out the method according to claim 6, comprising:

    c) a high-voltage electrode assembly (2), which is assigned to a high-voltage generator (3), with which it is chargeable with high-voltage pulses ; and

    d) a conveying device (6), in particular in the form of a conveyor belt (6) or a conveyor chain, arranged in a basin (5) which is filled or fillable with a process liquid (4), with which in the intended operation a material flow of a pourable, to be fragmented and/or to be weakened material (1), immersed in a process liquid (4), can be guided past the high-voltage electrode assembly (2) while high-voltage punctures through the material flow are produced by means of charging of the high-voltage electrode assembly (2) with high-voltage pulses,

    characterized in that the device is structured such that, in the intended operation, during the guiding past of the material flow, the central zone of the material flow is charged with high-voltage punctures, while the boundary zones of the material flow remain substantially unaffected by the high-voltage punctures, and wherein the device comprises a separation device (11, 14, 14a, 14b), by means of which in an intended operation the material (1) of the boundary zones of the material flow is separated from the material (1) of the central zone of the material flow downstream of the high-voltage electrode assembly (2).
15. Device according to claim 14, further comprising a re-feeding device for refeeding the by means of the separation device (11, 14, 14a, 14b) separated material (1) of the boundary zones of the material flow back into the material flow upstream of the high-voltage electrode assembly (2).

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