WO2001085298A1

WO2001085298A1 - Method and device for separating by sedimentation physically detectable particles from a particle flow

Info

Publication number: WO2001085298A1
Application number: PCT/EP2001/004938
Authority: WO
Inventors: Reiner Budach; Karlheinz Neubert
Original assignee: Bauer, Jeanette
Priority date: 2000-05-04
Filing date: 2001-05-02
Publication date: 2001-11-15
Also published as: DE10021779C1; AU2001260272A1; EP1286740A1; HK1049632A1

Abstract

The invention relates to a method and a device for separating by sedimentation particles from a particle flow contained in a carrier liquid. In order to improve separation efficiency and results, sedimented particles are diverted from the flow at given time intervals during the sedimentation operation in the direction of flow and upstream from flow obstacles without interrupting said operation.

Description

description

Method or device for sedimentation separation of physically detectable particles from a particle stream

The invention relates to a method and a device for sedimentation separation of physically detectable particles from a particle stream carried in a carrier liquid, in which the particle is passed over at least one threshold-like obstacle which runs essentially transversely to the flow direction, such that particles of lower specific weight are separated from the carrier liquid are preferably carried over the obstacle and particles of larger specific gravity settle in front of the obstacle in the direction of flow.

In known devices of the type mentioned here, the particle stream carried by the carrier liquid is carried forward primarily by a slope of a flow channel, on the bottom or the lower wall area of which there are a plurality of threshold-like obstacles which are oriented approximately transversely to the direction of flow.

A relative movement between the particle flow in the carrier liquid, which carries the particles to be separated out and particles of no interest, and the flow channel can also be brought about in that a foundation supporting the flow channel carries out oscillatory movements.

According to traditional methods of the type mentioned above, the gold diggers use sloping wash troughs that hold the precious metal-containing material and nuggets with cross bars. This happens because the Rubble and water to be searched pass the washing trough and have to overcome the crossbars. While stones or other particles in the water flow overcome the obstacles more easily due to the lower specific weight of their material and often lower density of the particle body in question and consequently higher buoyancy in the water forming the carrier liquid, particles of denser material sink in the direction of flow in front of the obstacle and remain in it the obstacle-filled washing gutter.

The hindrance of traditional institutions can also from the

Threshold shape have a different shape and may be replaced by wiper-like structures.

The conventional methods and the known devices have in common that in order to remove the particles that have to be separated from the obstacles in the direction of flow, the operation has to be interrupted, and that the efficiency of the known methods and devices is comparatively low, since there are obstacles in the direction of flow sedimenting particles, which may also include particles that cannot be separated, make the obstacle in question increasingly less effective in terms of sedimentation over a longer period of operation and the entire particle flow gradually overcomes due to a leveling of the threshold formed by the obstacle in the carrier liquid flow.

In order to avoid this disadvantageous effect, it is necessary with appropriate known methods and devices to interrupt the operation repeatedly in order to remove the particles to be separated from the area in the direction of flow in front of the obstacles, so that continuous operation is not possible with known methods or devices is. The System standstill during the emptying and cleaning phase represents an economic loss. If, in order to reduce this economic loss, the time intervals between emptying and cleaning the areas between the threshold-like obstacles are increased, the sedimentation separation efficiency deteriorates with the result that that the residual particle stream, which has been inadequately cleaned from the particles to be separated, has to be subjected to a chemical aftertreatment to improve the separation result, which is to be regarded as a cost disadvantage and as a disadvantage in terms of environmental pollution.

The object of the present invention is accordingly to achieve sedimentation separation of physically detectable particles from a particle stream carried in a carrier liquid in such a way that an improved separation efficiency is achieved, even with a small proportion of particles of interest to be separated, and with a small particle size, and with comparatively simple means continuous operation is made possible.

This object is achieved according to the invention by a method with the features of the appended claim 1. The invention also includes a device for carrying out such a method.

Advantageous refinements and developments are the subject of the claims subordinate to claim 1 and claim 4, the content of which is hereby expressly made part of the description without repeating the wording here.

The idea underlying the preferred embodiments of the present invention is primarily, but not exclusively, to be seen in the fact that the separation result does not affect the physical effect to leave physically detectable properties of the particles to be separated out, but to evaluate a detection result which arises due to the effectiveness of the physical differences between the particles to be separated from one another for the final separation of the particles of interest. This means, as it were, an amplification of the primary separation result based on physical differences between the particles to be separated.

A number of embodiments of the invention are explained below with reference to the drawings. In these represent:

1 shows a schematic illustration of a vertical longitudinal section through a washing trough for sedimentation separation of physically detectable particles from a particle stream guided in a carrier liquid according to the prior art;

FIG. 2 shows a representation similar to FIG. 1 of a device for sedimentation separation of the type specified here;

FIG. 3 shows a perspective, partially sectioned representation of a practical embodiment of a device according to FIG. 2 with components indicated in block symbols for controlling the same;

FIG. 4 shows a representation similar to FIG. 3 of a device for sedimentation separation according to a modification of the embodiment according to FIG. 3; 5 shows a similar illustration to FIGS. 3 and 4 of yet another, particularly expedient embodiment of a device for sedimentation separation; and

Fig. 6 is a partially drawn in axial vertical section reproduction of yet another embodiment of a device of the type specified here.

In Fig. 1, 1 denotes the bottom of an inclined washing trough. Side walls (not shown in FIG. 1) which adjoin the bottom 1 hold a particle stream 2 in the region above the bottom, which contains particles 3 of interest to be cut out by sedimentation separation and also particles 5 which are not of interest and are carried along with a carrier liquid of the particle stream up to a discharge end 4 contains. The particles 4 to be separated out by sedimentation separation differ from the particles 5 by a physically detectable property, namely in the present example by the greater specific weight of their material. It is assumed here that the particles to be separated out by sedimentation separation are 3 gold particles, while the particles of no interest consist of limestone. Because of the greater specific weight of their material and also because of their greater density, the particles 3 do not follow the carrier liquid flow over threshold-like obstacles 6 oriented approximately transversely to the particle flow, which protrude from the bottom 1 of the washing trough, but settle in relation to the flow direction in front of the obstacle 6 in the area 7, while the particles 5 are conveyed upwards by the carrier liquid flow in front of the obstacle 6 and then conveyed over the obstacle in order to exit together with the carrier liquid at the discharge end 4. This sedimentation separation mechanism - of a generally known type can be reinforced by arranging a whole series of obstacles on the bottom 1 of the washing trough in the direction of flow of the particle flow in the direction of flow of the particle flow and each accumulating in the areas 7 in front of the obstacles Form particles 3 to be separated out, which can each be removed from the regions 7, partially contaminated with a content of particles 5, as soon as the particle flow and the carrier liquid flow are each interrupted for specific operating intervals.

In the embodiment according to FIG. 2 is otherwise quite the same

Training as in the arrangement shown in Fig. 1, as is also made clear by using corresponding reference numerals, in the bottom 1 of the washing trough where the area 7 is in front of the threshold-like obstacle 6, a flap 8 is provided, which by of a drive 9 can be folded downwards via a coupling linkage 10 to a control signal and from the area 7 opens a gap-like opening oriented transversely to the particle flow direction to a discharge channel 11 which runs in the floor or under the floor 1 of the washing channel.

Neighboring area 7 and in the present case above the area

7 there is a detector 12 in the washing trough. This detector responds to a special physical property of the particles 3 accumulating in the area 7, which is preferably not the physical property which distinguishes the particles 3 from the particles 5 in the particle stream , The detector 12 can be an ultrasound detector or an X-ray detector or an optical detector or the like, insofar as these are embodiments of the type shown in FIG. 2, in which the detector 12 is arranged outside the particle flow and carrier liquid flow and through it onto the area 7 is oriented. On the training of the detector as Resistance detector or conductivity detector, or voltage detector or inductance detector or capacitance detector will be discussed in more detail below.

In any case, however, the detector 12 then generates a detector signal on its output line 13 when, after a certain operating time of the device, particles 3, to whose special physical property the detector 12 responds, have accumulated in the region 7. The detector signal on line 13, possibly via a control device, causes drive 9 to briefly pivot flap 8 downward, so that particles 3 located in region 7 above flap 8 are selectively discharged into channel 11, after which the flap 8 is closed again and during a further, continuously subsequent operating phase, the particle stream in the carrier liquid is again passed over the bottom 1 of the washing trough until the detector 12 responds again. An interruption of the flooding of the washing trough and a removal of particles 3 from the regions 7 from the side of the opening of the washing trough to be carried out at intervals during these interruptions is not necessary in the device according to FIG. 2.

Fig. 3 shows an embodiment in which the washing channel has an approximately horizontally oriented bottom 1. The bottom of the washing trough of the embodiment according to FIG. 3 can, however, also be inclined, as in the embodiment according to FIG. 2. Side walls 14 are placed close to the bottom 1. However, the side wall facing the viewer is cut off in the illustration according to FIG. 3. The general flow direction of the particle flow from particles to be separated or sedimented and particles of no interest remaining in the carrier liquid flow is indicated by the dash-dotted arrow P. The detector 12 in the embodiment according to FIG. 3 has the form of a conductivity detector or resistance detector which is connected via measuring lines 15 and 16 to strip-shaped measuring electrodes 17 and 18, respectively. Of these, the strip-shaped measuring electrode 17 is embedded in the lower part of the side wall of the threshold-like obstacle 6 directed against the flow direction of the particle flow and carrier liquid flow, while the strip-shaped measuring electrode 18 is embedded in the adjacent edge region of the surface of the flap 8.

The measuring line 16 is designed such that it bridges the area bridging the area between the bottom 1 of the washing trough and the flap 8 which can be folded down, or contains a slip ring arrangement which allows the flap 8 to move without interrupting the connection.

The conductivity detector or resistance detector 8 determines the conductance or the resistance of the volume region 7 corresponding to approximately a quarter of a circular cylinder between the mutually perpendicular boundary surfaces of the obstacle 6 on the one hand and the flap 8 on the other hand and compares the measured conductance or resistance value with a limit value that can be set on the detector 12. As soon as the measured value deviates significantly from the set comparison value, the detector 12 emits an output signal on the line 13, which causes the activation of the drive 9 via a control device 19, so that the flap 8 goes downwards for a certain, short period of time of the arrow K is folded away and particles to be separated which have accumulated in the region 7 are discharged into a channel below the wash basin bottom 1. If the detector 12 is a conductivity detector, the detector signal 13 is generated when the conductivity of the detected area 7 rises above a certain limit value due to sufficient sedimentation of particles to be separated out.

If the detector 12 is a resistance detector, the detector signal 13 is emitted when the resistance of the area 7 drops below a predetermined limit value due to the particle deposition.

Flows between the measuring electrodes 17 and 18 over the volume of the

Carrier liquid in the area 7, albeit a very small measuring current, it turns out that the electrode surfaces are attacked electrolytically very quickly, which can lead to falsifications of the detector result. According to a very useful detector design, the detector has the shape of a voltage detector. For this purpose, the area 7 is formed in cooperation with the measuring electrodes as a galvanic element, in which, for example, one measuring electrode is made of chrome and the other measuring electrode is made of silver or one measuring electrode is made of brass and the other measuring electrode is made of silver. Other pairs of materials that form a galvanic element in cooperation with the respective carrier liquid are also conceivable.

In the case in which there are no conductive particles 3 to be separated out in the space between the measuring electrodes 17 and 18, the galvanic element emits, for example, an output voltage of 0.2 volts.

A voltage detector circuit connected to the measuring electrodes contains a counter voltage source through which the output voltage of the galvanic element formed from the measuring electrode and the region 7 is compensated so that practically no current flows between the measuring electrodes and these are protected against an electrolytic attack on their surfaces.

Only when the measuring electrodes 17 and 18 are short-circuited by conductive particles to be separated out, does the output voltage of the galvanic element formed from the measuring electrodes and the carrier liquid volume collapse, which is detected by the voltage detector voltage and leads to the triggering of the detector signal. This type of detection works extremely sensitive and allows the separation of conductive particles in the milligram range.

If, as can be seen from the illustration in FIG. 4, the threshold-like obstacle 6 at the bottom 1 of the washing trough is inclined relative to the washing trough longitudinal axis, then the flow lines of the particle stream and the carrier liquid stream carrying it, also indicated by dash-dotted arrows P, also have components in the direction of the Extension of the inclined obstacle 6, such that particles 3 to be sedimented gradually settling in the area 7 at an angle between the side surface of the obstacle 6 directed against the flow and the bottom surface of the bottom 1 of the washing channel in the direction of the end closer to the viewer of area 7 move. There, for example, the increased specific conductivity compared to the particles 5 having particles 3 accumulate in front of measuring electrodes 20 and 21, which are embedded in the area of the end of the side face of the obstacle 6 that is closer to the observer of FIG. 4, and via measuring lines 22 or 23 are in turn connected to a conductivity detector 12 which, when sufficient conductivity is detected in the area 7 in front of the measuring electrodes 20 and 21, emits a detector signal via line 13 to the control device 19 in order to activate the drive 9 by means of the latter, similar to this is the case in the embodiment of FIG. 3. The flap 8 in the bottom 1 of the washing trough which can be pivoted downward by the drive 9 when it is activated, however, has a significantly shorter length in the direction across the washing trough in the embodiment of FIG. 4 than in the embodiment of FIG. 3 that when the drive 9 is excited due to a detector signal 13 emitted by the detector 12, essentially only that part of the base 1 of the washing trough which is in front of the measuring electrodes 20 and 21 is briefly folded down to collect particles 3 in precisely in this part of the region 7 to drain a channel located below the washing trough. This design has the advantage that a particularly sensitive sedimentation separation is achieved, that the area to be detected is kept small, that a high separation efficiency is achieved, and that the separation result is contaminated by relatively little particles that are not of interest, that is to say by a few particles 5, because during the folding down of the bottom of the washing trough, the entire width of the area in front of the obstacle 6 to the discharge channel does not open for the particles of interest which have been separated out by sedimentation separation.

If the measuring electrodes 20 and 21 are covered by an electrically insulating layer, they can, in a modification of the embodiment shown in FIG. 4, also be used as measuring electrodes for a detector 12 which responds to changes in capacitance.

A further embodiment, not shown in the drawing, can be seen in

Modification of that of Fig. 4 before that instead of the measuring electrodes 20 and 21 in the relevant area of the side wall of the threshold-like obstacle 6, an inductance sensor in the manner of a sound head is embedded, which forms an inductance detector in connection with the detector circuit 12. The Inductance sensor is excited by a high-frequency current and generates an alternating field in the area 7 which lies in front of it, which induces eddy currents in sedimented particles 3 which enter this area, which influence the excitation current of the inductance sensor and are thus detected by the circuit 12 can.

Ferromagnetic particles 3 can also be detected according to a similar principle familiar to the person skilled in the art.

As already indicated, several threshold-like obstacles 6 are connected one behind the other in the longitudinal direction of the washing gutter along a guard gutter on the floor 1 thereof in practical embodiments. 2 to 4 each show only a characteristic section of the washing trough in the vicinity of a threshold-like obstacle 6. With regard to this aspect, it should be noted in relation to FIG. 4 that when several threshold-like obstacles 6 are connected in series along the washing trough, these obstacles relative to the washing groove longitudinal axis with reference to a horizontal plane alternately enclose an angle of more than 90 ° and an angle of less than 90 °, in which case the flaps 8 respectively assigned to the obstacles 6 progressively along the washing gutter once near the washing gutter side wall (not shown) closer to the viewer of FIG. 4 and once are located near the washing gutter side wall (shown in FIG. 4) further away from the viewer. This training requires a further increase in the separation efficiency and an improvement in the separation result.

The embodiment according to FIG. 5 contains, as an obstacle 6 projecting over the bottom surface of the bottom 1 of the washing trough, a cylinder body which is embedded in a transverse gap in the bottom 1 of the washing trough and which has an approximately approximately 90 ° spanning part of its circumference is provided cylindrical sector-shaped cutout, which corresponds to the area 7 of the previously described embodiments. The part of the boundary surface of this cutout standing vertically in FIG. 5 corresponds to the side surface of the obstacle 6 directed towards the flow, and the part of the said cylindrical sector cutout lying horizontally in FIG. 5 corresponds to the flap 8 of the previously considered embodiments.

The cylinder provided with the cutout in the form of the cylinder sector is coupled to a drive 25 via a shaft 24. Measuring electrodes are embedded in the boundary surface of the cylindrical cutout, which in turn are denoted by 17 and 18 in analogy to the embodiment according to FIG. 3 in FIG. 5. Measuring lines 15 and 16, which are connected to the measuring electrodes 17 and 18, have a slip ring arrangement 26 connection to the detector circuit 12, which in the case of a conductivity increased by sedimented particles 3 in the area 7 between the measuring electrodes 17 and 18 has a detector signal 13 outputs a control device 19 which switches on the drive motor 25 via a control line 27. The drive motor 25 then rotates the cylinder forming the obstacle 6 by one full clockwise rotation.

The cylindrical sector-shaped section rotates from the area above the floor 1 of the washing trough into the area below the floor 1 of the washing trough, that is to say into the area of the discharge channel 11. As soon as this has taken place, sedimented particles 3 fall from the area 7 into the discharge channel 11 In order to support this process, the control device 19 switches on the spray device 29 and 30 by means of a pump Pu in a corresponding time assignment to the rotation of the cylinder by the motor 25, which spray nozzles 29 and 30 extend the cylinder sector-shaped section of the cylinder during its Clean the dwell time in the discharge duct 11 before the cutout returns to the position shown in FIG. 5.

Also applies to the embodiment according to FIG. 5, that in practical installations along the washing trough a plurality of cylinders, each forming a threshold-like obstacle 6, provided with cylinder sector-shaped cutouts, with associated drives 25 are provided one behind the other.

6 shows an embodiment in which the guard channel has the shape of a sedimentation drum 30. At the drum ends, stub shafts 31 and 32 are provided via suitable spoke constructions, which are supported by bearings 33 and 34 at different levels with respect to a foundation 35 such that the sedimenting drum 30 is rotatable about an axis oriented at an angle to the horizontal.

A spiral screw 36 made of square material is fastened to the inner wall of the drum, which causes the inner wall of the sedimenting drum to have an internal thread, as it were.

The sedimentation drum 30 can be driven either by means of a drive motor 37 or in a manner to be explained below by means of blading 38 at the lower end of the drum in the direction of the arrow R. Via an inlet line 39 from the higher side of the sedimentation drum 30, a particle stream entrained by a carrier liquid is input, which flows in the deepest part of the sedimentation drum 30 in each radial plane with respect to the drum axis to the lower end of the sedimentation drum and thereby the individual gears Screw spiral 36 overflows, as indicated by arrows P in Fig. 6. Particles to be separated out with a higher specific weight and higher density are deposited on each sides of the passages of the screw spiral 36 facing the upper end of the drum, while particles of no interest are flushed from the carrier liquid over the obstacle and conveyed to the lower end of the drum. The carrier liquid and the particles remaining in it leave the interior of the drum via the blades 38 which penetrate the wall of the drum and thereby set the sedimentation drum 30 in rotation. The drive motor 37 can either be used instead of the blades 38 to drive the drum or can rotate the drum during an initial operating phase until the blades 38 develop sufficient torque.

If this sedimentation drum rotates in the direction of the arrow R, the screw spiral 36 gradually conveys the material sedimented on its flanks facing the upper drum opening in the direction of the upper drum opening. On this path of travel caused by the rotation of the drum, the sedimented material encounters a detector 12 which rotates with the drum and is supported in the drum by suitable holding means, which detects a detector signal via line 13 when detectable particles pass by on the opposite flank of a spiral of the screw spiral 36 releases the control device 19, the control device 19 then causes via a line 27 the activation of a rotating drive with the drum 9 to pivot on a flap 8, which normally closes a breakthrough through the wall of the drum 30 in an area immediately before a passage of the screw spiral 36 , The activation signal 27 reaches the drive 9 in a specific timing to the instantaneous drum position derived, for example, from the drive 37, such that the flap 8 is opened when it is at the lowest level during the rotation of the drum, so that in the area in question accumulated in the path of the screw spiral 36 and gradually in this area from deep-lying drum areas conveyed material can be derived into a channel 11. Excess carrier liquid is emptied into an overflow channel 41 during the rotation of the drum and added to the carrier liquid stream remaining after the sedimentation, which emerges from the blading 38.

It is expressly pointed out here that the embodiment shown in FIG. 6 can also be modified in such a way that the flap 8 and the opening in the drum wall controlled by it, the drive 9 and the detector 12 are omitted. In this case, the particles of interest deposited during the rotation of the sedimentation drum are discharged at 40 and collected in the channel 41, which in this case then only serves to collect the material obtained by sedimentation separation.

Also with regard to the embodiments described above in connection with FIGS. 2 to 5, ^" one is essential, one is strong

Simplification leading modification pointed out. This provides for the actuation of the respective flap 8 or of the cylinder forming the obstacle 6 not to be made dependent on a detection result, but to carry out the removal of sedimented particles by actuating the closure member at regular intervals previously determined empirically for a system. Such simplified embodiments then lead to a very satisfactory one

Sedimentation result if the over a certain operating period

Content of the particles to be sedimented carried in the carrier liquid is relatively constant and relatively known. Finally, it should also be noted that sedimentation devices of the type specified here can be created as modules due to their simple and clear structure and can be connected in series or in parallel as desired and that they can be connected upstream or downstream of any other sorting method. n-

It should also be mentioned that different from those shown

Embodiments, the flanks opposite the particle flow and the carrier liquid flow in the threshold-like obstacles can also be provided with niche-like recesses in order to favor the retention of the particles to be separated out.

Claims

Expectations

1. Method for sedimentation separation of physically detectable particles (3) from a particle flow carried in a carrier liquid, in which this is passed over at least one threshold-like obstacle (6) which runs essentially transversely to the flow direction, such that particles of lower specific weight are preferred by the liquid are carried over the obstacle and particles (3) of greater specific gravity settle in the direction of flow in front of the obstacle, characterized in that the physically detectable particles from the area in front of the obstacle (6) are derived from the particle stream during the sedimentation separation at certain time intervals.

Method according spoke 1, characterized in that the

The presence of the particles (3) to be separated in front of the obstacle (6) is detected (12) and the sedimented particles (3) are derived depending on a detector signal (13).

3. The method according spoke 1 or 2, characterized in that the particle flow is directed relative to the flow direction oblique obstacles (Fig. 4, Fig. 6) and caused to move obliquely to the flow direction and that the derivation of the sedimented particles (3) at an end region of the movement obliquely to the direction of flow.

4. Device for sedimentation separation of physically detectable particles (3) from a particle flow carried in a carrier liquid, with at least one, essentially transverse to the flow direction extending obstacle (6), which rises from the bottom (1) of a flow channel, characterized in that in front of the obstacle (6) in the bottom (1) of the flow channel a closure member (8) separating it from a discharge channel (11) is arranged, the by means of a servo drive (9) at certain times in the sense of an opening or

Voltage detector circuit of a connection between the flow channel and the discharge channel can be actuated.

5. Device according to claim 4, characterized in that in front of the obstacle (6) on the presence of the physically detectable

Particle (3) responsive detector (12; 17, 18, 12; 20, 21, 12) is arranged, the output signal (13) via a control device (19)

Servo drive (9) activated to actuate the closure member (8).

6. Device according to claim 5, characterized in that the detector contains a pair of electrodes (17, 18; 20, 21) arranged in a region (7) in front of the obstacle (6), which with a conductivity detector circuit or resistance detector circuit or voltage detector circuit or capacitance detector circuit of the Detector (12) is connected.

Device according to claim 5, characterized in that the detector (12) contains an inductance sensor, in particular a high-frequency sound head, which is connected to an inductance measuring circuit of the detector.

Device according to one of claims 4 to 1, characterized in that the at least one obstacle (6) extends at an angle different from 90 ° to the longitudinal direction of the flow channel and that the closure member (8) on the end region which is distant with respect to the direction of flow the transverse extent of the obstacle in question is limited, on which the detector is also directed.

9. Device according to one of claims 4 to 8, characterized in that a plurality of obstacles (6) and associated closure members (8) is connected in series in the longitudinal direction of the flow channel.

10. The device according to spoke 8 and 9, characterized in that the obstacles (6) progressively alternately include an angle of more than 90 degrees and an angle of less than 90 degrees relative to the longitudinal axis of the flow channel in the flow direction.

11. Device according to one of claims 4 to 10, characterized in that the closure member has the shape of a cylinder inserted into a transverse gap of the bottom (1) of the flow channel with a cylindrical sector-shaped, spanning approximately a circumferential region of 90 degrees, the one in the closed position vertical wall forms a side surface of the obstacle (6) opposite to the flow and its horizontal wall in the closed position is flush with the surface of the bottom (1) of the flow channel (FIG. 5).

12. The device according spoke 4, characterized in that the flow channel is formed by a sedimentation drum (30) which on the inside as the at least one obstacle has a spiral screw (36) that the drum about its longitudinal axis, which is opposite the

Is horizontally inclined, rotatably and drivably mounted, that the particle flow and the carrier liquid flow can be entered at the higher end of the drum and can be supplied to the lower end of the drum via the screw threads of the screw spiral (36) and that flows to the each of the flanks of the passages of the screw spiral (36) facing the upper end of the drum sedimented particles can be discharged at the upper end or near the upper end.

13. The device according spoke 12, characterized in that instead of the discharge of the sedimented particles via a controlled by the closure member, the wall of the sedimentation drum (30) penetrating opening, the discharge of the sedimented particles is provided directly at the upper end of the sedimentation drum.

14. Device according to claim 12 or 13, characterized in that the rotary drive for the sedimentation drum (30) is provided by a turbine blading (38) provided at the lower end of the drum, which cooperates with the carrier liquid stream emerging at the lower end of the drum.

15. The device according to claim 6, in which a voltage detector circuit of the detector is connected to the pair of electrodes of the detector, characterized in that the electrodes of the pair of electrodes made of different metal, in particular silver and chrome or silver and

Brass, exist and in cooperation with the carrier liquid in said area (7) in front of the obstacle (6) form a galvanic element, the output voltage of which is compensated in a voltage detector circuit by means of a counter-voltage source, the output voltage of the galvanic element collapsing due to a short circuit between the electrodes can be detected by conductive particles to be separated out by means of the voltage detector circuit.