TW201805068A - Centrifugal separation apparatus and centrifugal separation method - Google Patents

Abstract

A centrifugal separation apparatus includes: a cylindrical basket (2) which is rotated about an axis line (O); a pusher plate (7) which is accommodated in the basket (2) and is provided so as to be integrally rotatable with the basket (2) and movable in an axis line direction relative to the basket (2), and which pushes a cake which is obtained by filtrating a processed material supplied into the basket (2) by a filtration screen (2a) toward an open end (2b) side of the basket (2); an extend retract drive portion (11) which moves by extending and retracting one of the pusher plate (7) and the basket (2) relative to the other along the axis line direction; a measurement portion which measures a pushing load of the extend retract drive portion (11) pushing the cake, in which at least one of the relative moving velocity of the pusher plate (7) and the basket (2), and an extending and retracting stroke of the pusher plate (7) and the basket (2) is controlled based on the pushing load measured by the measurement portion.

Description

Centrifugal separation device and centrifugal separation method

FIELD OF THE INVENTION The present invention relates to a push-type centrifugal separation device and a centrifugal separation method. A processed material supplied into a basket rotating around an axis is filtered by a filter provided in a main body portion of the basket, and The filter cake, which is accommodated in the basket and can be rotated integrally and can be relatively moved in the axial direction relative to the basket, discharges the filter cake that has been filtered out by the treatment object from the open end of the basket. This application claims priority based on Japanese Patent Application No. 2016-133666 filed in Japan on July 5, 2016, and the contents are incorporated herein by reference.

BACKGROUND OF THE INVENTION Such a push-type centrifugal separation device has disclosed, for example, a two-stage basket-type centrifugal separation device including an outer basket and an inner basket in Patent Document 1. The outer basket is rotatable about an axis, and the inner basket is rotatable. It is coaxially arranged in the outer basket to rotate integrally, and advances and retreats in the axial direction with respect to the outer basket. In this two-stage basket-type centrifugal separation device, a processed material filtered by centrifugation is supplied between a pressing plate and a circular plate-shaped distributor. The pressing plate is supported by an outer basket and is connected with The opening of the treatment object supply pipe is arranged in the inner basket so as to face each other, and the distributor is arranged so as to surround the opening of the treatment object supply pipe at a distance from the pressing plate.

In such a centrifugal separation device, the processed material supplied from the opening of the supply pipe to between the pressing plate and the dispenser is deposited on the inner peripheral surface of the filter provided in the main body portion of the inner basket by centrifugal force, and is filtered to form a filter. cake. Furthermore, by advancing the inner basket toward the open end side of the outer basket, filter cakes are also stacked in the axial direction of the inner basket. Next, the filter cake of the processed object is pushed by the pressing plate by the back of the inner basket relative to the outer basket, and is discharged to the inner peripheral surface of the outer basket. In addition, the filter cake discharged to the inner peripheral surface of the outer basket is further filtered by the screen of the outer basket, and is pushed out from the open end of the outer basket by being pushed by the advance of the inner basket. Prior technical literature Patent literature

[Patent Document 1] Japanese Patent Laid-Open No. 2014-091093

SUMMARY OF THE INVENTION Problems to be Solved by the Invention In such a centrifugal separation device, the relative movement of the basket and the pressing plate in the axial direction (in the centrifugal separation device described in Patent Document 1, the inner basket moves forward and backward with respect to the pressing plate). It is hydraulically driven by a hydraulic piston. Therefore, the movement stroke during the forward movement and the movement stroke during the reverse movement, and the movement speed during the forward movement and the movement speed during the reverse movement are respectively equal to each other.

In such a centrifugal separation device, the solid content of the processed material subjected to solid-liquid separation and dehydration treatment does not always have a fixed load on the centrifugal separation device, and it may occur due to changes in the supply amount of the processed material or the solid concentration in the processed material. Increase and decrease of load caused by solid content. When the solid content increases and the load increases due to an increase in the supply amount or solid concentration of the processed material, the thickness of the filter cake filtered from the processed material by the screen increases, and the filter formed on the inner peripheral surface of the screen The thickness of the cake layer will become uneven, and abnormal vibration may occur in the basket rotating at high speed.

Conversely, for the load caused by such a solid component, if the relative moving speed or moving stroke of the basket and the pressing plate is set to be large in advance, the thickness of the filter cake formed on the inner peripheral surface of the screen will become thin and remain at The amount of filter cake in the basket is also reduced and the residence time of the processed material in the basket is shortened. The factors that affect the dewatering performance of the centrifugal separation device are mainly the centrifugal force formed by the rotation of the basket and the residence time in the basket. Therefore, if the operation is performed with a short residence time, the dehydration performance of the centrifugal separation device will cause an excessive load on the solid content, and the dehydration performance of the centrifugal separation device will not be fully exerted.

The present invention is made under such a background, and the purpose thereof is to provide a centrifugal separation device and a centrifugal separation method, which can respond to the increase or decrease of the load accompanying the change in the supply amount of the processed material or the change in the solid concentration, so that the thickness of the filter cake can be increased. It maintains uniformity to prevent the occurrence of abnormal vibration, and can exert dehydration performance without being over or under. Solutions to problems

The first aspect of the centrifugal separation device of the present invention is provided with: a basket having a cylindrical shape, a filter screen is provided on the main body and rotatable around an axis; a pressing plate is housed in the basket and can be rotated integrally, and It is arranged to relatively move the basket in the axial direction, and push the filter cake filtered by the filter material from the processed material supplied into the basket to the open end side of the basket; the advancement and retraction drive part makes the pushing plate and the One side of the basket moves relative to the other side in the axial direction, and moves relatively; and a measurement unit for measuring a pushing load, which is one of the pressing plate and the basket of the filter cake by the forward and backward driving unit The pushing load of the advancing and retreating driving part when the advancing and retreating is pushed to the open end side of the basket, the centrifugal separation device controls the relative moving speed of the pushing plate and the basket by the advancing and retreating driving part according to the pushing load measured by the measuring part And at least one of the forward and backward strokes of one of the pressing plate and the basket to the other.

A first aspect of the centrifugal separation method of the present invention is to supply a treatment object into a cylindrical basket provided with a filter on the main body and rotating around the axis, and filtering the filter from the treatment object through the filter. The cake is pushed and discharged toward the open end side of the basket by a pressing plate, and the pressing plate is accommodated in the basket and can be integrally rotated, and is arranged to relatively move the basket in the axial direction. In the separation method, one of the pressing plate and the basket is moved relative to the other in the axial direction by the advance and retreat drive section, and the push load is measured by the measurement section. The push load is the filter cake by the advance and retreat. The pushing load of the advancing and retreating driving section when one of the pressing plate and the basket advances and retreats to the open end side of the basket is controlled by the driving section, and the advancing and retreating driving section is controlled based on the pressing load measured by the measuring section. At least one of a relative moving speed of the pressing plate and the basket, and one of the pressing plate and the basket moving forward and backward with respect to the other.

In such a first aspect of the centrifugal separation device and the first aspect of the centrifugal separation method, for example, the centrifugal separation device described in Patent Document 1, the pressing plate is located at a certain position in the axial direction, and if the basket can be in the axial direction The forward and backward movement controls at least one of the moving speed and the forward and backward stroke of the basket to the pressing plate by the forward and backward driving unit. On the contrary, if the basket is located at a certain position in the axial direction and the pressing plate can move forward and backward in the axial direction, at least one of the moving speed of the pressing plate and the forward and backward stroke performed by the forward and backward driving unit is controlled.

Therefore, in any case, if the above-mentioned pushing load tends to increase, that is, when the load of solid content may increase due to the increase in the supply amount of the treatment material or the increase in the solid concentration of the treatment material, and the filter cake changes, the control is performed. Increase at least one of the relative moving speed and the stroke. Thereby, the supply amount of the processed material per unit length in the axial direction of the filter screen is reduced, and the thickness of the filter cake can be uniformized. Therefore, it is possible to prevent abnormal vibration and the like due to the formation of a cake of uneven thickness in the screen of the basket rotating at high speed, and stable filtration can be achieved.

On the other hand, when the load of the solid content decreases due to a decrease in the supply amount of the processed material or the decrease in the solid concentration of the processed material, and the pushing load tends to decrease, control is performed so that the relative moving speed and The aforementioned stroke is reduced by at least one of them. Thereby, the supply amount of the processed material per unit length of the screen in the axial direction can be increased. Therefore, it is possible to prevent the formation of filter cakes of uneven thickness, and to ensure the residence time of the processed materials in the basket for a long time, and to exert the dehydration performance of the centrifugal separation device without being over or under, and to promote balanced and efficient filtration.

In addition, even in order to control the relative moving speed of the pressing plate and the basket, one of the basket and the pressing plate moves forward and backward to the other by, for example, hydraulic driving by a conventional hydraulic piston. There is a difference in the flow path of the operating oil between forward and reverse, or a speed controller is provided, and the flow path of the discharge side of the cylinder is divided, and the difference in the setting of the discharge speed of the operating oil can be controlled thereby. However, in this case, when the forward / backward switching is performed, the oil pressure may become unstable and it may become difficult to control the relative moving speed. In addition, it is almost impossible to control the stroke between the pushing plate and the basket by hydraulic pressure driven by a common hydraulic piston.

Therefore, as described above, it is necessary to stably control at least one of the relative moving speed of the pressing plate and the basket and the stroke of one of the pressing plate and the basket to the other. Speed control is driven by an electric motor that has high responsivity or can be switched in and out at any stroke.

Therefore, when one of the basket and the pressing plate is driven, the rotation of an electric motor (servo motor) transmitted to a screw shaft such as a ball screw is screwed to the screw shaft by using a nut coaxially mounted on the piston rod. The linear motion converted into a piston rod can be a so-called electric cylinder. Furthermore, it is possible to use a cylinder liner that directly moves the piston rod linearly by an electric linear motor. Or it is advisable to use two or more chains to engage with each other and repeatedly move forward by the electric motor in a columnar shape, or to untie the chain and pull it back to make it recede for linear movement, also known as snap-actuated actuation器 等。 And other.

In particular, when the forward / backward driving section is driven by an electric motor, the measurement section can measure the pushing load from the current value of the electric motor of the forward / backward driving section. Therefore, it is possible to measure the load of the solid matter that is actually applied to the advancing / retracting driving portion in real time, so that more reliable and stable control can be achieved. Such a measurement unit may use, for example, a load meter provided in the forward / backward driving unit when the forward / backward driving unit is an electric motor, let alone a hydraulic drive.

According to the present invention, the thickness of the filter cake can be uniformly maintained to prevent the occurrence of abnormal vibration and the dewatering performance can be exhibited without being excessive or inadequate, regardless of the increase or decrease of the load accompanying the change in the supply amount of the processed material or the change in the solid concentration. And can promote stable and efficient filtration.

Detailed Description of the Preferred Embodiment FIG. 1 or FIG. 3 shows a first embodiment of the centrifugal separation device of the present invention, and the present invention is applied to a two-stage type having an outer basket and an inner basket as described in Patent Document 1. An example of a basket-type centrifuge. That is, the centrifugal separation device in this embodiment includes a cylindrical outer basket 1 with an outer screen 1a mounted on the main body and centered on the horizontal axis O, and a cylindrical inner basket 2 which is coaxially housed. An inner screen 2a is installed in the outer basket 1 and a main body portion. In this first embodiment, the inner basket 2 is a basket in the present invention. The outer screen 1a or the inner screen 2a is, for example, a cylindrical wire screen or a screen.

A circular open end 1b, 2b is provided at one end in the axis O direction of the cylindrical outer basket 1 and the inner basket 2 (the right end in the axis O direction in FIGS. 1 to 3), and the other ends (FIGS. 1 to FIG. The left end in the direction of the axis O in 3) is a bottomed cylindrical shape that is attached to and held by the disk-shaped holding plates 1c and 2c. The length in the axis O direction of the inner basket 2 is shorter than the length in the axis O direction of the outer basket 1. The inner basket 2 is housed in the housing 3 and rotates about the axis O integrally with the outer basket 1. In addition, the outer diameter of the open end 2b of the inner basket 2 is set such that, for example, a ring-shaped other pressing plate is provided on the open end 2b and can be slidably connected to the inner peripheral surface of the screen 1a outside the outer basket 1. the size of.

The holding plate 1c of the outer basket 1 is installed at one end of the hollow main shaft 5. The main shaft 5 is rotatably supported by the bearing 4 and is installed in the housing 3 along the axis O. The rotational force of a motor or the like is transmitted to a pulley (not shown) and the main shaft 5 rotates, whereby the outer basket 1 rotates about the axis O. In addition, the push shaft 6 is inserted into the main shaft 5 and can be rotated integrally by a key (not shown) and can be advanced and retracted in the axis O direction. One end of the pressing shaft 6 slidably penetrates the holding plate 1c of the outer basket 1 and is mounted on the holding plate 2c of the inner basket 2, whereby the inner basket 2 can also rotate integrally with respect to the outer basket 1 and can be inside the outer basket 1. The other side moves forward and backward in the direction of the axis O.

Further, a plurality of support shafts 1d are holding plates 1c attached to the outer basket 1, and are spaced apart from each other in the circumferential direction at positions separated from the axis O toward the outer peripheral side, and extend parallel to the axis O on the one end side. The support shafts 1d slidably penetrate the holding plate 2c and protrude into the inner basket 2. At one end of the support shafts 1d, a disc-shaped pressing plate 7 having an outer diameter that can be slidably connected to the inner peripheral surface of the inner screen 2a is mounted. Therefore, the pressing plate 7 can rotate integrally with the outer basket 1 and the inner basket 2 about the axis O coaxially, and can relatively move in the direction of the axis O relative to the inner basket 2.

Further, a circular plate-shaped dispersion plate (dispenser) 8 having an opening in the center and the pressing plate 7 are integrally supported on the other end side of the pressing plate 7 with a gap therebetween. In addition, the supply pipe 9 of the treatment object is attached to and inserted into the housing 3. The supply pipe 9 is inserted into the opening portion of the dispersion plate 8 through the open ends 1 b and 2 b of the outer basket 1 and the inner basket 2, and the supply port of the supply pipe 9 is opened between the pressing plate 7 and the dispersion plate 8.

Further, a slightly U-shaped filter cake accommodating ring 3a opened toward the inner peripheral side along a section along the axis O is arranged on the outer periphery of the open end 1b of the outer basket 1 so as to be supported by the housing 3 and surround the open end 1b. A filter cake chute (not shown) is provided on the filter cake accommodating ring 3a, and the filter cake discharged from the open end 1b of the outer basket 1 is accommodated in the filter cake accommodating ring 3a, and then installed through the filter cake chute. The discharge port 3b below the casing 3 is discharged.

On the other hand, the other end of the pressing shaft 6 protrudes more than the other end of the main shaft 5, and the other end of the protruding pressing shaft 6 is connected to the advance and retreat drive portion 11 via the bearing box 10. The advance and retreat drive portion 11 allows the advance The pressing shaft 6 is rotated, and the pressing shaft 6 is moved forward and backward in the direction of the axis O for each inner basket 2. The bearing housing 10 has a structure in which the other end of the pressing shaft 6 is rotatably supported by a bearing (not shown) and the like, and the pressing shaft 6 that rotates integrally with the main shaft 5 is not rotated. It is mounted on the axis O in an integrally advancing and retreating manner with the pressing shaft 6.

Furthermore, the forward and backward drive unit 11 in this embodiment is driven by an electric motor, and particularly transmits the rotation of the electric motor (servo motor) 11a to a screw shaft such as a ball screw (not shown). The ball bolt is on the axis O. It is arranged in the cylinder box 11b so as to extend in the direction. A nut, which is coaxially mounted on a piston rod (not shown), is screwed to the screw shaft, and the forward / backward driving portion 11 converts the rotation of the electric motor 11a into linear motion of the piston rod through the screw shaft and the nut. The forward / backward driving unit 11 is a so-called electric cylinder, a servo cylinder, or an electric actuator.

In one embodiment of the centrifugal separation method of the present invention using the thus configured centrifugal separation device, the outer basket 1 and the inner basket 2 are rotated integrally, and a solid (liquid) turbid treatment substance (slurry) is supplied from the supply pipe 9. . In this embodiment, the supplied processed material hits the pressing plate 7 and is dispersed from between the pressing plate 7 and the dispersion plate 8 to the outer peripheral side by centrifugal force, and adheres to the inner peripheral surface of the inner screen 2 a of the inner basket 2. Therefore, when the processed material is supplied in this way, and the inner basket 2 is advanced from the state in which the inner basket 2 is moved backward relative to the pressing plate 7 as shown in FIG. 2, the processed material is continuously stacked in the axial direction of the inner basket 2 and filtered inside the advanced inner basket 2. The inner peripheral surface of the net 2a is filtered by centrifugal force to form a filter cake of a processed material.

Secondly, when the inner basket 2 that has advanced in this way reaches the end of the forward stroke and turns back as shown in FIG. 3, the filter cake of the processed material accumulated on the inner peripheral surface of the inner screen 2a is opposed to the inner basket 2 that is withdrawn. The pressing plates 7 which are relatively advanced are sequentially pressed to one end side of the inner basket 2. The filter cake (filter cake) deposited on the one-side treatment object will gradually be discharged from the open end 2b toward the inner peripheral surface of the screen 1a outside the outer basket 1, or will be continuously stacked in the direction of the axis O and subjected to centrifugal force Further filtering. Furthermore, if the supply amount or solid concentration of the processed material to be supplied has stabilized, the pressing load of the advancement and retraction drive portion 11 when the inner basket 2 advances and the filter cake of the processed material is pushed is also stable within a predetermined range.

Then, the filter cake of the filtered matter deposited on the inner peripheral surface of the outer screen 1a in this way is forwarded by the next time the inner basket 2 reaches the stroke end of the backward stroke, and is then opened by the open end 2b of the inner basket 2. Or other pressing plates (not shown) provided on the open end 2b are sequentially pressed to one end side. Next, the filter cake deposited on one end side is discharged from the open end 1b of the outer basket 1 to the filter cake accommodating ring 3a, and further, as described above, through the filter cake slideway (not shown) from the discharge port of the casing 3. 3b is discharged.

The centrifugal separation device having the above-mentioned configuration is provided with a measuring unit 15 for measuring the pressing load of the advancing and retracting driving unit 11 when the filter cake of the processed material passes through the advancing and retracting driving unit in the following cases: 11 The advancement and retraction drive section 11 when the pushing plate 7 and the inner basket 2 of the basket of the present invention (in this embodiment, the inner basket 2) advance and retreat and are pushed to the open end 2b side of the inner basket 2. Pushing load. In the above-mentioned centrifugal separation method using the centrifugal separation device and the centrifugal separation device, the relative moving speed of the pressing plate 7 and the inner basket 2 performed by the advancing and retreating driving portion 11 is controlled based on the pressing load measured by the measuring portion 15 and the pushing speed One of the pressure plate 7 and the inner basket 2 is at least one of the forward and backward strokes of the other.

That is, in the centrifugal separation device and the centrifugal separation method of this embodiment, when there is a tendency that the supply amount or solid concentration of a processed substance changes from a stable state as described above, and the pushing load is also larger than the predetermined range When increasing, control is performed to increase at least one of the relative moving speed and the stroke. On the contrary, when the pushing load tends to decrease from the predetermined range, control is performed so that at least one of the relative moving speed and the stroke is reduced.

In addition, in the present embodiment, the measurement unit 15 measures the current value of the electric motor 11a of the forward / backward drive unit 11 to measure the pushing load. The above-mentioned control can be automatically and easily controlled by inputting a program in advance to a control unit such as a computer or the like that includes a known constituent member for controlling the electric motor 11a, such as a CPU or a memory. The measured pressing load controls the electric motor 11a.

Specifically, in the present embodiment, the pressing plate 7 is mounted on the main shaft 5 through the support shaft 1d and the holding plate 1c of the outer basket 1 and is fixed in the axis O direction. In contrast, the inner basket 2 is on the axis through the pressing shaft 6 Move forward and backward in the O direction. Therefore, when the control increases the relative moving speed when the pushing load increases, the control is performed as follows. That is, as shown in FIG. 2, the state in which the distance D between the open end 2 b and the pressing plate 7 in the axis O direction is reduced from the inner basket 2 toward the other end side in the axis O direction is controlled as shown in FIG. 2. 2 advances toward one end side in the direction of the axis O, and as shown in FIG. 3, the open end 2b of the inner basket 2 is away from the pressing plate 7, and the relative moving speed in the direction in which the interval D increases becomes larger. On the contrary, the relative moving speed from the state where the interval D is large to the direction where it is small may be increased.

On the contrary, when the pushing load is reduced from the predetermined range, the relative moving speed from the state in which the interval D shown in FIG. 2 is small to the direction in which the interval D shown in FIG. 3 becomes larger is controlled, and from In the state where the interval D shown in FIG. 3 is large, the relative moving speed decreases in the direction in which the interval D shown in FIG. 2 becomes smaller.

On the other hand, the case where one of the pressing plate 7 and the inner basket 2 (inner basket 2 in the present embodiment) is controlled relative to the forward and backward stroke of the other side (in this embodiment, the pressing plate 7) will be described. For example, the advance and retreat stroke of the inner basket 2 when the pushing load is within the predetermined range is set in advance to be smaller than the maximum stroke of the piston rod of the advance and retreat driving section 11. When the pushing load measured by the measuring unit 15 exceeds the predetermined range and becomes larger, the inner basket 2 is moved forward and backward with a stroke larger than the forward and backward stroke of the inner basket 2 when it is located in the predetermined range. Conversely, when the pushing load becomes smaller than the predetermined range, the inner basket 2 is moved forward and backward with a stroke smaller than the stroke of the inner basket 2 when it is within the predetermined range.

In the centrifugal separation device and the centrifugal separation method configured as described above, when the supply amount of the processed material or the solid concentration increases and the pushing load exceeds the predetermined range, the pushing plate 7 and the inner basket 2 by the advance and retreat driving section 11 are increased. The relative moving speed can achieve the following effects. That is, when the interval D shown in FIG. 2 is small and the interval D is large as shown in FIG. 3, the processed objects deposited on the inner peripheral surface of the inner screen 2 a are pressed by the pressing plate 7 and then supplied to The amount of solids contained in the processed material of the inner screen 2a becomes smaller per unit length in the direction of the axis O. Therefore, the thickness of the filter cake remaining on the inner peripheral surface of the inner screen 2a during centrifugal filtration of the processed product can be made uniform with the supply amount or solid concentration and the thickness of the filter cake when the load is within a predetermined range is stabilized. Into.

In addition, from a state where the interval D shown in FIG. 3 is large to a state where the interval D shown in FIG. 2 is small, the inner basket 2 retracts toward the other end side of the pressing plate 7 in the direction of the axis O to push the opening of the inner basket 2. The following effects can be obtained in the processed material on the end 2b side. That is, the processed material supplied from the pressing plate 7 and the dispersion plate 8 is stacked on the processing object (inner periphery) stacked on one end side of the pressing plate 7. At this time, because the relative moving speed of the inner basket 2 with respect to the pressing plate 7 is large, the solids in the treatments stacked per unit length in the direction of the axis O are also reduced, which can prevent the filter cake from becoming too thick.

On the other hand, when the supply amount of the processed material or the solid concentration is stable and the pushing load exceeds the predetermined range, if the stroke of the inner basket 2 with respect to the pushing plate 7 is increased, the following effects can be obtained. That is, regardless of whether the interval D becomes larger or smaller, the processed material with a higher supply amount or solid concentration is dispersed over a wider range in the axis O direction and is supplied to the inner peripheral surface of the inner screen 2a. The cake became thicker. In addition, when the pushing load is smaller than a predetermined range, if the advance and retreat strokes of the inner basket 2 are reduced, the processed material having a lower supply amount or solid concentration is supplied to the inner peripheral surface of the inner screen 2a within a relatively small range. Prevent the filter cake from becoming too thin.

In this way, according to the centrifugal separator and the centrifugal separation method configured as described above, when the supply amount of the processed substance or the solid concentration of the processed substance is increased, the load of the solid is increased, and when the load is pushed, the load is increased. At least one of the relative moving speed of the inner basket 2 with respect to the pressing plate 7 and the forward and backward strokes can prevent the filter cake from becoming too thick and uniformize the filter cake thickness. On the contrary, when the supply amount of the processed material or the solid concentration decreases and the pushing load becomes small, by reducing at least one of the relative moving speed and the stroke, it is possible to prevent the thickness of the filter cake from becoming too thin, or to make the filter cake thinner. The cake thickness is uniform.

Therefore, even if the supply amount of the processed material or the solid concentration fluctuates, it is possible to prevent the unevenness of the thickness of the filter cake from being formed on the inner peripheral surface of the screen 2a inside the inner basket 2 rotating at high speed. Therefore, the possibility of abnormal vibration of the inner basket 2 due to the uneven thickness of the filter cake can be prevented, and filtration of the stable processed material by centrifugation can be promoted. In addition, even when the supply amount of the processed material or the solid concentration is reduced, the residence time of the processed material in the inner basket 2 can be ensured for a long time by reducing the relative moving speed or the forward and backward strokes. Therefore, the performance of the centrifugal separation device can be brought into play, without over or under, and efficient filtration can be achieved.

Further, in the centrifugal separation device of this embodiment, as the advancement and retraction drive portion 11 for advancing and retreating the inner basket 2 in the direction of the axis O with respect to the pressing plate 7, a rotation of the electric motor 11a is transmitted from the piston through the screw shaft and the nut. The lever is converted into an electric cylinder that moves linearly against the shaft 6. In addition, the forward / backward driving unit 11 using such an electric motor 11a has a higher speed response when the forward / backward switching is performed than a conventional hydraulic drive. Even when the relative moving speed or the forward / backward stroke is increased or decreased as described above, Controlling the rotation of the electric motor 11a allows easy and quick response. Therefore, it is particularly effective in the case of controlling the centrifugal separator or the centrifugal separation method having the above-mentioned configuration.

Furthermore, the forward / backward driving unit 11 using such an electric motor 11a is not limited to an electric cylinder that converts the rotation of the electric motor 11a into a linear motion of a piston rod by using a screw shaft and a nut as described in the above embodiment. For example, it may be a cylinder liner that directly moves the piston rod and the pressing shaft 6 linearly by an electric linear motor. It can also be a so-called snap-in actuator, etc., which can make two or more chains connected to the pressing shaft 6 engage with each other and repeatedly advance in a columnar shape by an electric motor, or release the engagement of the chain and pull it back. It retreats for linear motion.

In addition to the centrifugal separation device using the electric motor 11a as the forward / backward driving section 11, in this embodiment, the measurement section 15 measures the electric power in the forward / backward driving section 11 when measuring the aforementioned pressing load when pressing the cake of the processed object. The current value of the motor 11a is used to measure the pressing load. Therefore, the above-mentioned pressing load when pressing the filter cake of the processed object can be measured in real time, and the measured result can be quickly reflected in the control of the advancing / retracting driving unit 11, so that more reliable and stable control can be promoted. Furthermore, it may be controlled as follows: if at least one of the relative moving speed and the stroke controlled by the pushing load measured in accordance with the pushing load is a preset upper or lower limit value, it is regarded as abnormal. An alarm is issued and the centrifuge is stopped.

4 and 5 show a second embodiment of the centrifugal separation device of the present invention. Portions common to the centrifugal separation device of the first embodiment are given the same reference numerals and descriptions thereof are omitted. In the centrifugal separation device of the second embodiment shown in FIGS. 4 and 5, the other end portion in the direction of the axis O, which is not shown, is the same as the centrifugal separation device of the first embodiment, so the illustration is omitted.

In the first embodiment, the inner basket 2 is housed in the outer basket 1 and can be rotated integrally. The inner basket 2 is mounted on the pressing shaft 6 to advance and retreat in the direction of the axis O. The outer basket 1 and the outer basket 1 are supported by the outer basket 1. The pressing plate 7 is maintained at a fixed position in the direction of the axis O, whereby the pressing plate 7 can be relatively moved in the direction of the axis O relative to the basket (inner basket 2). In the second embodiment, a single basket 21 is provided with a strainer 21a on the main body portion and has an open end 21b at one end in the direction of the axis O. The single basket 21 is attached to one end of the main shaft 5 through a holding plate 21c. The basket 21 is maintained at a fixed position in the direction of the axis O, and the outer diameter of the pressing plate 22 which can be slidably connected to the inner peripheral surface of the filter 21a is coaxially mounted on one end of the pressing shaft 6 inserted into the holding plate 21c. Advance and retreat in the direction of the axis O. Thereby, the pressing plate 22 can be relatively moved in the direction of the axis O with respect to the basket 21.

Therefore, in the second embodiment, the basket 21 and the open end 21b of the basket 21 are at a fixed position in the axis O direction, and the pressing plate 22 can move forward and backward in the axis O direction. Therefore, the direction in which the distance D between the pressing plate 22 and the open end 21b of the basket 21 in the axis O direction becomes large becomes the state where the pressing plate 22 advances from inside the basket 21 as shown in FIG. 4 and moves backward as shown in FIG. 5. Direction. In addition, the direction in which the interval D becomes smaller becomes the direction when the pressing plate 22 moves backward from the state shown in FIG. 5 and advances as shown in FIG. 4. Therefore, when the pressing plate 22 is advanced, the filter cake of the processed material accumulated on the inner peripheral surface of the screen 21a of the basket 21 is discharged from the open end 21b side of the basket 21 to the filter cake accommodating ring 3a.

In the second embodiment, based on the pressing load of the electric motor 11a measured by the measurement unit 15 included in the forward / backward driving portion 11, the relative moving speed of the pressing plate 22 and the basket 21 performed by the forward / backward driving portion 11 and At least one of the forward and backward strokes of the pressing plate 22 relative to the basket 21. Specifically, when the pushing load is measured based on the current value of the electric motor 11a, and the state in which the supply amount of the processed material or the solid concentration is stable and the pushing load is also stable, and there is a tendency that the pushing load increases, the relative load is controlled. At least one of the moving speed and the stroke is increased. Conversely, if there is a tendency for the thrust load to decrease, the control reduces at least one of the relative movement speed and the stroke.

In the second embodiment, at least one of the relative moving speed of the pressing plate 22 with respect to the basket 21 and the forward and backward strokes are controlled when there is a change in the supply amount of the processed material or the solid concentration in the processed material, thereby maintaining uniformity The thickness of the cake formed on the inner peripheral surface of the screen 21a. Therefore, it is possible to prevent abnormal vibration of the basket 21, and to promote filtration of the centrifugal separation of a stable processed material. In addition, when the supply amount of the processed material or the solid concentration decreases, the relative moving speed of the pressing plate 22 or the forward / backward stroke can be reduced to ensure the residence time of the processed material in the basket 21. Therefore, the performance of the centrifugal separation device can be exerted without being over or under, and efficient filtration can be achieved.

In the present embodiment, the forward / backward driving unit 11 constituted by the electric motor 11a is also used. By controlling the electric motor 11a, the relative movement speed or the forward / backward stroke can be easily and quickly controlled. In addition, since the pushing load can be measured in real time based on the current value of the electric motor 11a, it is possible to respond quickly to sudden changes in the supply of processed materials or changes in the solid concentration.

In the second embodiment or the first embodiment, in addition to the forward / backward driving section 11 using the electric motor 11a, the current value of the electric motor 11a is measured by the measuring section 15 to measure the pushing load. It is not limited to this, for example, a load load meter is provided as the measuring unit 15 on the pressing shaft 6 or the like, and the relative positions of the pressing plates 7, 22 and the baskets 2, 21 may be controlled based on the pressing load measured by the load meter. Movement speed or forward and backward stroke.

If the pushing load is measured by a load meter, the present invention can also be applied to the movement of one of the basket and the pushing plate to the other side by the hydraulic driving of a conventional hydraulic piston, especially when controlling the relative moving speed. Centrifugal separation device and centrifugal separation method. For example, it can be applied by making a difference in the flow path of the operating oil between forward and backward, or by providing a speed controller, or by dividing the cylinder discharge side flow path to set a difference in the discharge speed of the operating oil.

However, in such an advance and retreat driving unit driven by such a hydraulic pressure, when the advance and retreat of the pressing plates 7, 22 and the baskets 2, 21 is switched, the hydraulic pressure becomes unstable and it may be difficult to control a predetermined relative moving speed. In addition, the viscosity of the working oil changes due to the oil temperature, and the oil pressure is difficult to stabilize. For oil temperature management, cooling water is required to cool the working oil, and oil changes due to the deterioration of the working oil under long-term operation, Or regular replacement of oil and gas filters and other places of maintenance also become troublesome. Furthermore, in the hydraulic driving by a general hydraulic piston, it is almost impossible to control the forward and backward strokes of the pressing plate and the basket.

Therefore, to control at least one of the relative moving speed of the pressing plate and the basket by the forward and backward driving unit, and the forward and backward stroke of one of the pressing plate and the basket relative to the other, it is preferable to implement the first and second implementations of the present invention. The form uses an electric motor to move forward and backward. In addition, in the first embodiment, the present invention is applied to a two-stage basket having an outer basket 1 and an inner basket 2 and a centrifugal separation device and a centrifugal separation method provided with a single basket 21 in the second embodiment. Although the description is made, the present invention is also applicable to a centrifugal separation device and a centrifugal separation method having baskets of three or more stages. Industrial availability

According to the centrifugal separation device and the centrifugal separation method of the present invention, the thickness of the filter cake can be maintained uniform and abnormal vibration can be prevented from occurring regardless of the increase or decrease of the load accompanying the change in the supply amount of the processed material or the solid concentration. Dewatering performance without over or under, can promote stable and efficient filtration.

1‧‧‧ Outer basket
1a‧‧‧ Outer Filter
1b‧‧‧ Open end of outer basket 1
1c‧‧‧ Outer basket retaining plate
1d‧‧‧ support shaft
2‧‧‧ inner basket (basket)
2a‧‧‧Inner filter
2b‧‧‧ Open end of inner basket 2
2c‧‧‧Retaining plate
3‧‧‧shell
3a‧‧‧Containing ring
3b‧‧‧Exhaust
4‧‧‧bearing
5‧‧‧ Spindle
6‧‧‧ push shaft
7,22‧‧‧Pressing plate
8‧‧‧ Dispersion plate
9‧‧‧ supply pipe
10‧‧‧bearing box
11‧‧‧ forward and backward drive
11a‧‧‧ Electric Motor
11b‧‧‧cylinder box
15‧‧‧Measurement Department
21‧‧‧ basket
21a‧‧‧Filter
21b‧‧‧Open end of basket 21
O‧‧‧horizontal axis
D‧‧‧ interval

FIG. 1 is a schematic cross-sectional view showing a first embodiment of a centrifugal separation device of the present invention. FIG. 2 is an enlarged cross-sectional view showing the periphery of the basket in a state where the inner basket is retracted relative to the pressing plate in the embodiment shown in FIG. 1. FIG. FIG. 3 is an enlarged cross-sectional view showing the periphery of the basket in a state where the inner basket advances with respect to the pressing plate in the embodiment shown in FIG. 1. FIG. Fig. 4 is an enlarged cross-sectional view showing the periphery of the basket in a state where the pressing plate is advanced relative to the basket in the second embodiment of the centrifugal separation device of the present invention. Fig. 5 is an enlarged sectional view showing the periphery of the basket in a state where the pressing plate is retracted relative to the basket in the embodiment shown in Fig. 4.

1‧‧‧ Outer basket

1a‧‧‧ Outer Filter

1b‧‧‧ Open end of outer basket 1

1c‧‧‧ Outer basket retaining plate

1d‧‧‧ support shaft

2‧‧‧ inner basket (basket)

2a‧‧‧Inner filter

2b‧‧‧ Open end of inner basket 2

2c‧‧‧Retaining plate

3‧‧‧shell

3a‧‧‧Containing ring

3b‧‧‧Exhaust

4‧‧‧bearing

5‧‧‧ Spindle

6‧‧‧ push shaft

7‧‧‧Pushing plate

8‧‧‧ Dispersion plate

9‧‧‧ supply pipe

10‧‧‧bearing box

11‧‧‧ forward and backward drive

11a‧‧‧ Electric Motor

11b‧‧‧cylinder box

15‧‧‧Measurement Department

O‧‧‧horizontal axis

D‧‧‧ interval

Claims (9)

A centrifugal separation device includes: a basket having a cylindrical shape, a filter screen is provided on a main body portion and can rotate around an axis; a pressing plate is accommodated in the basket and can be rotated integrally, and is arranged to be able to rotate the basket in the foregoing Relatively move in the axial direction, and push the filter cake filtered by the filter screen from the processed material supplied into the basket to the open end side of the basket; the advance and retreat drive part makes the pressing plate and the basket One of them moves relative to the other in the axial direction, and moves relatively; and a measurement unit for measuring a pushing load, which is the pushing plate and the basket performed by the filter cake by the pushing and retreating driving unit. When one of them advances and retreats to the open end side of the basket, the pushing load of the advancing and retreating drive unit, and the centrifugal separation device controls the advancing and retreating drive unit based on the pushing load measured by the measuring unit. At least one of a relative moving speed of the pressing plate and the basket, and one of the pressing plate and the basket moving forward and backward with respect to the other. In the centrifugal separation device of claim 1, when the pushing load tends to increase, control is performed to increase at least one of the relative moving speed and the stroke. If the centrifugal separation device of claim 1 or 2, wherein the pushing load tends to decrease, control is performed to reduce at least one of the relative moving speed and the stroke. The centrifugal separation device according to claim 1 or 2, wherein the forward and backward driving unit is driven by an electric motor. The centrifugal separation method according to claim 4, wherein the measurement unit measures the pushing load from a current value of the electric motor in the forward / backward drive unit. The centrifugal separation method according to any one of claims 1 to 4, wherein the measurement section is a load meter provided in the advance and retreat drive section. A centrifugal separation method is to supply a treatment object into a cylindrical basket provided with a strainer on the main body and rotating around the axis, and filter cakes filtered from the treatment substance by the aforementioned strainer and push the plate The basket is pushed and discharged toward the open end side of the basket, and the push plate is housed in the basket and can be rotated integrally, and is arranged to be relatively movable in the axial direction of the basket. The centrifugal separation method One of the pressing plate and the basket is moved relatively to the other in the axial direction by the advancing and retreating driving section, and the pressing load is measured by a measuring section. The pressing load is the filter cake by The pressing load of the advancement and retraction driving unit when the advancement and retreat of the pressing plate and the basket by the advancement and retraction driving unit is pushed to the open end side of the basket is based on the pressing force measured by the measuring unit. The load controls the relative moving speed of the pressing plate and the basket performed by the advancing and retreating driving unit, and the forward and backward stroke of one of the pressing plate and the basket to the other At least one. If the telecentric separation method of claim 7 is used, when the pushing load tends to increase, control is performed to increase at least one of the relative moving speed and the stroke. If the telecentric separation method of claim 7 or 8 is used, when the pushing load tends to decrease, control is performed to reduce at least one of the relative moving speed and the stroke.