Thickener feeding device and thickener

Abstract

The present application discloses a thickener feeding device and a thickener, and relates to the technical field of thickeners. The thickener feeding device comprises: a feeding pipeline; a spoiler, each spoiler is arranged in the feeding pipeline, and a spoiler flocculant channel is arranged in the spoiler; a runner assembly, a runner assembly is arranged on a spoiler, the runner assembly can rotate relative to the spoiler, a runner assembly flocculant channel is arranged on the runner assembly, and the runner assembly flocculant channel is connected with the spoiler flocculant channel; a blade, a runner assembly is provided with a plurality of blades that follow the runner assembly and are arranged along the circumferential direction of the runner assembly, each blade is provided with a blade flocculant channel, and each blade flocculant channel is connected with the runner assembly flocculant channel and the feeding pipeline; a first flocculant feeding device, which is connected with the spoiler flocculant channel. The present application can solve the problem that the flocculant can only contact with the ore pulp to be settled on the liquid surface.

Description

Technical Field

[0001] The present application relates to the technical field of thickeners, and in particular to a thickener feeding device and a thickener. Background Art

[0002] Thickener is a solid-liquid separation equipment based on gravity sedimentation. It can concentrate slurry with solid weight of 10%~20% into underflow slurry with solid content of 45%~55% through gravity sedimentation. With the help of the slow-running (1 / 3~1 / 5r / min) rake installed in the thickener, the thickened underflow slurry is discharged from the underflow port at the bottom of the thickener.

[0003] During the use of the thickener, it is usually necessary to mix the slurry to be settled with the flocculant to achieve rapid sedimentation of the slurry to be settled. Then, in the prior art, most flocculants are sprayed into the feed pipe to mix with the slurry to be settled. However, since the flocculant is added at a single point and the flocculant density is less than the slurry density, the flocculant only exists in the upper part of the slurry. The mixed slurry is not fully mixed, and the particles in the slurry cannot effectively combine with the flocculant molecules to form large agglomerates, thereby affecting the flocculation effect.

[0004] In addition, the feed pipeline is usually limited in length. How to achieve sufficient mixing within the limited pipeline length is also one of the difficulties of the prior art.

[0005] In particular, when feeding the slurry to be settled, the feed amount is usually adjusted according to the sedimentation conditions. For example, during the sedimentation process, the high-efficiency thickener will be divided into a compression zone, a transition zone and a clarification zone after the slurry to be settled is settled. However, the volumes of the three zones are not constant. If the volume of the compression zone becomes larger, it means that the slurry to be settled entering the pool body cannot be digested. At this time, the feed flow rate needs to be reduced. Therefore, the feed flow rate may be adjusted accordingly. At this time, if the same amount of flocculant is used again, it will cause the problem of too much flocculant.

[0006] Therefore, it is desired to have a technical solution to overcome or at least alleviate at least one of the above-mentioned defects of the prior art. Summary of the invention

[0007] The object of the present application is to provide a thickener feeding device to overcome or at least alleviate at least one of the above-mentioned defects of the prior art.

[0008] To achieve the above objectives, the present application provides a thickener feeding device, the thickener feeding device comprising:

[0009] A feed pipe, wherein the feed pipe is provided with a feed inlet and a discharge outlet;

[0010] A spoiler, wherein the number of the spoilers is multiple, each spoiler is arranged in the feed pipe, and each spoiler is provided with a spoiler flocculant channel;

[0011] A runner assembly, wherein the number of the runner assemblies is multiple, each of the runner assemblies is arranged in the feed pipe, a runner assembly is arranged on a spoiler, the runner assembly can rotate relative to the spoiler, a runner assembly flocculant channel is arranged on the runner assembly, and the runner assembly flocculant channel is communicated with the flocculant channel of the spoiler;

[0012] Blades, the number of the blades is multiple, a rotor assembly is provided with multiple blades that move with the rotor assembly and are arranged along the circumferential direction of the rotor assembly, each blade is provided with a blade flocculant channel, each blade flocculant channel is communicated with the rotor assembly flocculant channel, and each blade flocculant channel is communicated with the feed pipe;

[0013] A first flocculant feeding device, wherein the first flocculant feeding device is connected to the spoiler flocculant channel; wherein

[0014] The slurry to be settled enters from the feed port of the feed pipe and flows out from the discharge port of the feed pipe;

[0015] The first flocculant supply device is used to supply the flocculant to the blade flocculant channel through the spoiler flocculant channel and the rotor assembly flocculant channel;

[0016] The impeller assembly is used to rotate under the impetus of the ore pulp to be settled in the feed pipe, so that the flocculant in the blade flocculant channel of the blade on the impeller assembly enters the feed pipe and mixes with the ore pulp to be settled through the action of centrifugal force during rotation.

[0017] Optionally, the thickener feeding device further comprises:

[0018] A spray assembly, wherein the number of the spray assemblies is multiple, each of the spray assemblies comprises a spray head and a spray pipe connected to the spray head, and the spray head is arranged in the feed pipe;

[0019] A second flocculant supply device is connected to the spraying pipeline and is used to provide flocculant to the spraying head.

[0020] Optionally, one end of the spoiler is connected to the feed pipe, and the other end of the spoiler is connected to the runner assembly via a sealed bearing.

[0021] Optionally, the wheel assembly comprises a wheel body, the wheel body is connected to the sealing bearing, and the wheel body is provided with the wheel assembly flocculant channel.

[0022] Optionally, the rotor body is a cylindrical body, and a plurality of through holes are provided on the rotor body, and each through hole is connected to the flocculant channel of the rotor assembly;

[0023] The blade is a cylindrical body with openings at both ends and a hollow interior, and one end of one of the blades is connected to one of the through holes.

[0024] Optionally, the wheel assembly further includes a rotation speed sensor, the number of the rotation speed sensors is the same as the number of the sealed bearings, and one rotation speed sensor is arranged on one of the sealed bearings to obtain the rotation speed of the sealed bearing.

[0025] Optionally, the inner wall on one side of the feed pipe connected to the spoiler is the top inner wall, the inner wall on the other side opposite to the inner wall is the bottom inner wall, and the distance between the position where the wheel assembly is set and the top inner wall is the same as the distance between the position where the wheel assembly is set and the bottom inner wall.

[0026] Optionally, the spray head is arranged on the top inner wall, and a spray head is arranged between every two spoilers.

[0027] Optionally, the first flocculant feeding device comprises:

[0028] A flocculant storage box, wherein the flocculant is arranged in the flocculant storage box, and the flocculant storage box is provided with flocculant discharge ports having the same number as the spoilers;

[0029] A delivery pipeline, the number of which is the same as the number of the flocculant discharge ports, one end of a delivery pipeline is connected to one of the flocculant discharge ports, and the other end is connected to one of the spoiler flocculant channels;

[0030] Solenoid stop valves, the number of which is the same as the number of the delivery pipelines, one solenoid stop valve being arranged on one delivery pipeline to control the connection or closing of the delivery pipeline;

[0031] A controller is connected to each of the rotation speed sensors and each of the electromagnetic stop valves, and is used to obtain the rotation speed information transmitted by the rotation speed sensor and control the operation of the electromagnetic stop valve.

[0032] The present application also provides a thickener, which includes the thickener feeding device as described above.

[0033] The thickener feeding device of the present application has the following advantages by arranging a combination of a spoiler, a rotor assembly and blades in the feeding pipeline:

[0034] 1. By setting the spoiler, the impeller assembly and the blades can penetrate into the interior of the feed pipe, so that the flocculant entering the feed pipe through the blades can contact the part below the liquid surface of the slurry to be settled, thereby solving the problem that the flocculant can only contact the slurry to be settled on the liquid surface.

[0035] 2. The amount of flocculant added is linked to the flow rate and flow velocity of the slurry to be settled. When the flow rate and flow velocity of the slurry to be settled are large, the blades will be driven to rotate quickly, thereby releasing more flocculants. When the flow velocity is slow or small, the rotation speed of the blades will decrease, thereby reducing the amount of flocculant released. In this way, the amount of flocculant released is combined with the flow rate and flow velocity of the slurry to be settled, so that the amount of flocculant released can be adaptively adjusted without the need to control the amount of flocculant added through a complex electronic control system.

[0036] 3. Through the push of the slurry to be settled, the blades can achieve automatic turbulence in the local area, which can promote more complete mixing of the flocculant and the slurry to be settled in the limited feed pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic structural diagram of a thickener feeding device according to an embodiment of the present application.

[0038] Figure 2 yes Figure 1 Another structural schematic diagram of the thickener feeding device is shown.

[0039] Figure 3 yes Figure 1 A schematic diagram of the structure of the spoiler and the wheel assembly in the thickener feeding device is shown.

[0040] Reference numerals:

[0041] 1. Feed pipe; 11. Feed inlet; 12. Discharge outlet; 2. Spoiler; 3. Rotor assembly; 4. Blades; 5. First flocculant feeding device; 61. Spray head; 62. Spray pipe; 7. Second flocculant feeding device; 21. Sealed bearing; 31-rotor body; 32-motor; 51. Flocculant storage box; 52. Delivery pipe. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical scheme and advantages of the implementation of this application clearer, the technical scheme in the embodiment of this application will be described in more detail below in conjunction with the drawings in the embodiment of this application. In the drawings, the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The described embodiments are part of the embodiments of this application, not all of them. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain this application, and should not be construed as limitations on this application. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. The embodiments of this application are described in detail below in conjunction with the drawings.

[0043] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the scope of protection of the present application.

[0044] Figure 1 It is a schematic structural diagram of a thickener feeding device according to an embodiment of the present application. Figure 2 yes Figure 1 Another schematic structural diagram of the thickener feeding device is shown. Figure 3 yes Figure 1 A schematic diagram of the structure of the spoiler and the wheel assembly in the thickener feeding device is shown.

[0045] like Figures 1 to 3 The thickener feeding device shown comprises a feeding pipe 1 , a spoiler 2 , a rotor assembly 3 , blades 4 and a first flocculant supply device 5 .

[0046] In this embodiment, the feed pipe 1 is provided with a feed inlet 11 and a discharge outlet 12;

[0047] There are multiple spoilers 2, each of which is arranged in the feed pipe 1, and each spoiler 2 is provided with a spoiler flocculant channel;

[0048] There are multiple runner assemblies 3, each of which is arranged in the feed pipe (1), one runner assembly 3 is arranged on one spoiler 2, the runner assembly 3 can rotate relative to the spoiler 2, and a runner assembly flocculant channel is arranged on the runner assembly 3, and the runner assembly flocculant channel is connected to the spoiler flocculant channel;

[0049] There are multiple blades 4, and one rotor assembly 3 is provided with multiple blades 4 that move with the rotor assembly 3 and are arranged along the circumferential direction of the rotor assembly 3. Each blade 4 is provided with a blade flocculant channel, and each blade flocculant channel is connected to the rotor assembly flocculant channel, and each blade flocculant channel is connected to the feed pipe; the first flocculant feeding device 5 is connected to the spoiler flocculant channel; wherein,

[0050] The slurry to be settled enters from the feed port 11 of the feed pipe 1 and flows out from the discharge port 12 of the feed pipe 1;

[0051] The first flocculant supply device 5 is used to supply the flocculant to the blade flocculant channel through the spoiler flocculant channel and the blade flocculant channel;

[0052] The impeller assembly 3 is used to rotate under the impetus of the slurry to be settled in the feed pipe 1, so that the flocculant in the flocculant channel of the blade 4 on the impeller assembly 3 enters the feed pipe 1 through the action of centrifugal force during rotation and mixes with the slurry to be settled.

[0053] The thickener feeding device of the present application has the following advantages by arranging a combination of a spoiler, a rotor assembly and blades in the feeding pipeline:

[0054] 1. By setting the spoiler, the impeller assembly and the blades can penetrate into the interior of the feed pipe, so that the flocculant entering the feed pipe through the blades can contact the part below the liquid surface of the slurry to be settled, thereby solving the problem that the flocculant can only contact the slurry to be settled on the liquid surface.

[0055] 2. The amount of flocculant added is linked to the flow rate and flow velocity of the slurry to be settled. When the flow rate and flow velocity of the slurry to be settled are large, the blades will be driven to rotate quickly, thereby releasing more flocculants. When the flow velocity is slow or small, the rotation speed of the blades will decrease, thereby reducing the amount of flocculant released. In this way, the amount of flocculant released is combined with the flow rate and flow velocity of the slurry to be settled, so that the amount of flocculant released can be adaptively adjusted.

[0056] 3. Through the push of the slurry to be settled, the blades can achieve automatic turbulence in the local area, which can promote more complete mixing of the flocculant and the slurry to be settled in the limited feed pipeline.

[0057] In this embodiment, one end of the spoiler 2 is connected to the inner wall of the feed pipe 1, and the other end is provided with a runner assembly 3.

[0058] In this embodiment, the spoiler is a medium-hole structure with openings at both ends. With this structure, the flocculant delivered from the first flocculant supply device 5 can be directly delivered to the flocculant channel of the impeller assembly through gravity or other mechanisms (for example, a screw feeder).

[0059] See also Figure 1 In this embodiment, the thickener feeding device further includes a spray assembly and a second flocculant feeding device 7. The number of the spray assemblies is multiple, and each spray assembly includes a spray head 61 and a spray pipe 62 connected to the spray head 61. The spray head 61 is arranged in the feeding pipe 1;

[0060] The second flocculant supply device 7 is connected to the spraying pipe 62 and is used to provide flocculant to the spraying head 61 .

[0061] In this embodiment, the spray head 61 is at a certain distance from the liquid surface of the slurry to be settled when it enters the feed pipe. In this way, the spray head can spray flocculant on the liquid surface of the slurry to be settled, and the blades can provide flocculant to the inside of the slurry to be settled, so that both the surface and the inside of the slurry to be settled have sufficient flocculant.

[0062] In this embodiment, the size of the spoiler, the size of the runner assembly and the size of the impeller can be set as required, see Figure 1 In this embodiment, by setting the size of the spoiler, the size of the runner assembly and the size of the impeller, the impeller can be located in the width direction of the feed pipe ( Figure 1 the middle part of the up-down direction).

[0063] In this embodiment, the feed pipe may be a cylindrical pipe with a circular cross-section, or may be a pipe of other shapes.

[0064] In this embodiment, the spoiler can be a vertical plate, ie, perpendicular to the flow direction of the slurry to be settled, or an inclined plate, ie, at an angle to the flow direction of the slurry to be settled.

[0065] See also Figure 1 to Figure 2 In this embodiment, one end of the spoiler 2 is connected to the feed pipe 1, and the other end of the spoiler 2 is connected to the runner assembly 3 through a sealed bearing 21.

[0066] See also Figure 1 to Figure 2 The wheel assembly includes a wheel body 31 , which is connected to the sealing bearing 21 , and a wheel assembly flocculant channel is provided on the wheel body 31 .

[0067] In this embodiment, the rotor body 31 is a cylindrical body, and a plurality of through holes are provided on the rotor body 31, and each through hole is connected to the flocculant channel of the rotor assembly;

[0068] The blade 4 is a cylindrical body with openings at both ends and a hollow interior, and one end of each blade 4 is connected to a through hole.

[0069] In this embodiment, an opening is provided at one end of the impeller body 31, and the end is connected to the outer ring of the sealed bearing, so that the flocculant entering from the spoiler flocculant channel of the spoiler directly enters the impeller body 31 through the opening at the end, and enters each blade through each through hole of the impeller body 31.

[0070] In this embodiment, the opening of the end of the blade 4 that is not connected to the through hole of the impeller body 31 is an oblique opening.

[0071] In this embodiment, the blades 4 can be welded to the impeller body 31 .

[0072] In an alternative embodiment, the rotating wheel assembly further includes a motor 32, the number of the motors 32 is the same as the number of the sealed bearings 21, and one motor 32 is connected to the outer ring of one sealed bearing 21 to provide a rotational force for the sealed bearing 21, thereby rotating the outer ring of the sealed bearing 21, thereby driving the rotating wheel assembly 3 to rotate. For example, the motor can drive the outer ring of the sealed bearing through a crank-connecting rod mechanism, a planetary gear system, or other transmission systems.

[0073] In this embodiment, the sealed bearing and the runner assembly may be connected in a detachable manner, for example, by bolts.

[0074] In this embodiment, when the flow rate of the slurry to be settled is slow and the flocculant provided by the rotation of the blades is insufficient, auxiliary rotation can be performed by a motor.

[0075] In this embodiment, the wheel assembly further includes a rotation speed sensor. The number of the rotation speed sensors is the same as the number of the sealed bearings. One rotation speed sensor is arranged on one of the sealed bearings 21 to obtain the rotation speed of the sealed bearing 21 .

[0076] By obtaining the rotation speed, the approximate amount of flocculant entering the feed pipe through the blades can be understood. Specifically, through experiments, the relationship between the rotation speed and the amount of flocculant thrown into the feed pipe by the blades according to the centrifugal force can be understood.

[0077] In this embodiment, the blade 4 is a cylindrical body with openings at both ends and a hollow interior, and one end of one of the blades (4) is connected to one of the through holes.

[0078] In this embodiment, the first flocculant feeding device 5 includes a flocculant storage box 51, a delivery pipeline 52, an electromagnetic stop valve and a controller, wherein:

[0079] The flocculant storage box 51 is provided with flocculant, and the flocculant storage box 51 is provided with flocculant discharge ports having the same number as the spoilers;

[0080] The number of the delivery pipes 52 is the same as the number of the flocculant discharge ports. One end of a delivery pipe 52 is connected to one flocculant discharge port, and the other end is connected to one spoiler flocculant channel.

[0081] The number of the electromagnetic stop valves is the same as the number of the delivery pipelines 52. One electromagnetic stop valve is disposed on one delivery pipeline 52 to control the connection or closing of the delivery pipeline 52.

[0082] The controller is communicated with each speed sensor and each electromagnetic stop valve respectively, and is used for obtaining the speed information transmitted by the speed sensor and controlling the operation of the electromagnetic stop valve.

[0083] In this way, flocculant can be selectively provided to one or more impellers as needed. When the required amount of flocculant is not large, flocculant does not need to be provided to some of the impellers. At this time, the rotation of the impeller can be controlled by a motor, so that the impeller can be used only as a stirring and mixing device.

[0084] In this embodiment, the area of ​​the impeller surface in contact with the liquid can be set according to user needs.

[0085] In this embodiment, the provision of flocculant through the impeller and the provision of flocculant through the spray assembly can be combined as needed. For example, when the flow rate is small, the flocculant and the impeller can be provided only through the spray assembly, and when the flow rate is large, it can be provided through both the impeller and the spray assembly.

[0086] The present application divides the provision of flocculants into two provision methods (spray assembly or impeller), and both the number of spray assemblies and impellers are multiple, so that they can be freely matched according to different types of flocculants (because different types of flocculants may require different amounts to be provided), so that the thickener feeding device of the present application can be suitable for different slurries to be settled and different flocculants.

[0087] The present application also provides a thickener, which includes the thickener feeding device as described above.

[0088] Finally, it should be pointed out that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application is described in detail with reference to the above embodiments, a person skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A thickener feeding device, characterized in that: The thickener feeding device comprises: A feed pipe (1), wherein the feed pipe (1) is provided with a feed inlet (11) and a discharge outlet (12); A spoiler (2), wherein the number of the spoilers (2) is plural, each spoiler (2) is arranged in the feed pipe (1), and each spoiler (2) is provided with a spoiler flocculant channel; A runner assembly (3), wherein the number of the runner assemblies (3) is plural, each of the runner assemblies (3) is arranged in the feed pipe (1), a runner assembly (3) is arranged on a spoiler (2), the runner assembly (3) is rotatable relative to the spoiler (2), a runner assembly flocculant channel is arranged on the runner assembly (3), and the runner assembly flocculant channel is communicated with the spoiler flocculant channel; Blades (4), the number of the blades (4) is plural, a rotor assembly (3) is provided with a plurality of blades (4) which follow the rotor assembly (3) and are arranged along the circumferential direction of the rotor assembly (3), each blade (4) is provided with a blade flocculant channel, each blade flocculant channel is communicated with the rotor assembly flocculant channel, and each blade flocculant channel is communicated with the feed pipe; A first flocculant supply device (5), the first flocculant supply device (5) is connected to the spoiler flocculant channel; wherein: The slurry to be settled enters from the feed port (11) of the feed pipe (1) and flows out from the discharge port (12) of the feed pipe (1); The first flocculant supply device (5) is used to supply the flocculant to the blade flocculant channel through the spoiler flocculant channel and the rotor assembly flocculant channel; The rotor assembly (3) is used to rotate under the impetus of the ore pulp to be settled in the feed pipe (1), so that the flocculant in the blade flocculant channel of the blade (4) located on the rotor assembly (3) enters the feed pipe (1) and is mixed with the ore pulp to be settled due to the action of centrifugal force during the rotation process.

2. The thickener feeding device according to claim 1, characterized in that: The thickener feeding device further comprises: A spray assembly, wherein the number of the spray assemblies is multiple, each spray assembly comprises a spray head (61) and a spray pipe (62) connected to the spray head (61), and the spray head (61) is arranged in the feed pipe (1); A second flocculant supply device (7), the second flocculant supply device (7) is connected to the spraying pipe (62) and is used to provide flocculant to the spraying head (61).

3. The thickener feeding device according to claim 2, characterized in that: One end of the spoiler (2) is connected to the feed pipe (1), and the other end of the spoiler (2) is connected to the rotor assembly (3) via a sealed bearing (21).

4. The thickener feeding device according to claim 3, characterized in that: The wheel assembly comprises a wheel body (31), the wheel body (31) is connected to the outer ring of the sealing bearing (21), and the wheel body (31) is provided with a flocculant channel of the wheel assembly.

5. The thickener feeding device according to claim 4, characterized in that: The rotor body (31) is a cylindrical body, and a plurality of through holes are provided on the rotor body (31), and each through hole is connected to the flocculant channel of the rotor assembly; The blade (4) is a cylindrical body with openings at both ends and a hollow interior, and one end of a blade (4) is connected to one through hole.

6. The thickener feed device according to claim 5, characterized in that: The wheel assembly further comprises a rotation speed sensor, the number of which is the same as the number of the sealed bearings (21), and one rotation speed sensor is arranged on one of the sealed bearings (21) to obtain the rotation speed of the sealed bearing (21).

7. The thickener feed device according to claim 6, characterized in that: The inner wall of the feed pipe (1) on one side connected to the spoiler (2) is a top inner wall, and the inner wall on the other side opposite to the inner wall is a bottom inner wall, and the distance between the position where the wheel assembly (3) is arranged and the top inner wall is the same as the distance between the position where the wheel assembly (3) is arranged and the bottom inner wall.

8. The thickener feed device according to claim 7, characterized in that: The spray head (61) is arranged on the top inner wall, and a spray head (61) is arranged between every two spoilers (2).

9. The thickener feed device according to claim 8, characterized in that The first flocculant feeding device (5) comprises: A flocculant storage box (51), wherein the flocculant is arranged in the flocculant storage box (51), and the flocculant storage box (51) is provided with flocculant discharge ports having the same number as the spoilers; a delivery pipeline (52), the number of the delivery pipelines (52) being the same as the number of the flocculant discharge ports, one end of a delivery pipeline (52) being connected to one of the flocculant discharge ports, and the other end being connected to one of the spoiler flocculant channels; Solenoid stop valves, the number of the solenoid stop valves being the same as the number of the delivery pipelines (52), one solenoid stop valve being arranged on one delivery pipeline (52) and being used to control the connection or closing of the delivery pipeline (52); A controller is connected to each of the rotation speed sensors and each of the electromagnetic stop valves, and is used to obtain the rotation speed information transmitted by the rotation speed sensor and control the operation of the electromagnetic stop valve.

10. A thickener, characterized in that: The thickener comprises a thickener feed device as claimed in any one of claims 1 to 9.

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