JP2005125245A - Centrifugal filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a centrifugal filter capable of efficiently and securely recovering a cake, and enhancing maintenance performance in filtration of slurry. <P>SOLUTION: In the centrifugal filter in which a shaft center is placed so as to become vertical, a casing is formed of a freely opened and closed covering plate covering the upper end surface, the lower end surface of a rotary basket is opened, a rotary shaft and driving means are connected to a top plate of the upper end surface, and slurry supply means and cake discharge means are penetrated through a base plate and are inserted from the lower end opening port of the rotary basket to the inside. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a centrifugal filter that separates slurry into solid and liquid by centrifugal force, and more particularly to a vertical centrifugal filter in which the axis of a rotating rotating basket that is a filtering member is arranged vertically. It is.

In many industrial fields such as food, medicine, biotechnology, etc., in a solid-liquid separation operation that separates a slurry containing solids into liquid and solids, it has a rotating body that rotates at high speed, that is, a large number of liquid passage holes. 2. Description of the Related Art Centrifugal filtration machines that use a filter medium stretched on the inner peripheral surface of a basket to separate solids and liquids due to the high centrifugal force of the rotating basket are used. Among the centrifugal filters, many vertical centrifugal filters in which the axis of a rotating rotating basket is arranged in the vertical direction are used for slurry purification, clarification, and collection of valuable materials.

As shown in the longitudinal sectional view of FIG. 3 and the plan view of the rotating basket of FIG. 4, the conventional vertical centrifugal filter is arranged so that the axis is in the vertical direction, and the cylindrical side wall 103 and the upper end surface of the cylinder are arranged. A cylindrical casing 119 formed by an upper lid 105 that covers the lower side of the cylinder and a lower plate 104 that closes the lower end surface of the cylinder, and a filtrate discharge pipe 112 connected to the lower end of the cylindrical side wall 103 and a cake discharge pipe 108 connected to the lower plate 104. The cylindrical casing 119 is coaxially provided, the upper end surface is opened, the annular dam 101C projecting in the radial direction inside the upper end opening, the cylindrical peripheral wall 101A having a large number of liquid passage holes, and the cylinder The bottom plate 101B is formed with a bottom plate 101B, and a plurality of cake discharge ports 114 are formed at predetermined intervals at positions facing the cake discharge pipe 108 of the cylindrical casing in the vertical direction by rotation. The rotating basket 101 is connected to the shaft center portion of the bottom plate 101B of the rotating basket through one end through a bearing portion 132 provided on the shaft center portion of the lower plate 104 of the cylindrical casing, and via the belt 133 on the other end side. The rotating shaft 102 connected to the rotation driving device 131, the filter medium 110 stretched on the inner peripheral surface of the rotating basket peripheral wall 101A, and the upper lid 105 of the cylindrical casing are inserted into the rotating basket from the upper end opening. The slurry supply means 106 and the cake discharge means 107 are provided.

In the centrifugal filter having the above-described structure, the rotary basket 101 is rotated by the rotation driving device 131 via the rotary shaft 102, and the slurry supplied into the rotary basket 101 from the slurry supply means 106 by the centrifugal force by the rotation is filtered 110. The cake 111 formed on the filter medium is scraped off by a cake scraping knife as the cake discharging means 107, and discharged from the cake discharge port 114 of the rotating basket bottom plate 101B through the cake discharge pipe 108 of the cylindrical casing. However, when discharging the cake 111 from the rotating basket 101, the partition 113 at the connecting portion between the bottom plate 101B of the rotating basket and the rotating shaft 102 hinders the discharging of the cake, and it takes time to discharge the cake. Further, if the cake is discharged while the rotating basket 101 is rotated at a high speed, the cake is consolidated by rapid discharging of the cake, and the cake discharge port 114 may be blocked by the cake. Therefore, it is necessary to decelerate the rotation of the rotating basket 101 to a low speed. In addition, it takes more time to discharge the cake.

Further, as one of the structures for discharging the cake, there is a structure for discharging the scraped cake from the rotating basket through a suction tube.
In the above discharge method, the cake is discharged from the cake discharge port on the bottom plate of the rotating basket instead of the cake discharge port on the lower plate of the rotating basket. The problem of clogging of the cake discharge port can be solved because of the absence of suction, but it is necessary to install a suction device and a suction pipe to collect the scraped cake. It takes time and the equipment cost including the suction device is very expensive. Patent Document 1 describes an example of a centrifugal filter equipped with a cake discharging mechanism using a suction tube.
JP 2000-317347 A

The problem to be solved is that in the conventional centrifugal filter structure, in order to connect the rotating basket 101 to the rotating shaft 102, a connecting portion must be secured on the rotating basket bottom plate 101B on the cake discharge side. Since the partition 113 that partitions the discharge port 114 is indispensable, it is difficult to secure a sufficiently large cake discharge port 114, and when the cake is discharged from the rotating basket 101, the bottom plate 101B of the rotating basket and the rotating shaft 102 The partition portion 113 of the connecting portion hinders the cake discharge, and takes time to discharge the cake. Further, if the cake is discharged while the rotating basket 101 is rotated at a high speed, the cake is consolidated by rapid discharging of the cake, and the cake discharge port 114 may be blocked by the cake. Therefore, it is necessary to reduce the rotation of the rotating basket 101 to a low speed. In addition, it takes time to discharge the cake.

In order to solve the above-mentioned problems, a first invention is a cylindrical casing disposed so that its axis is in the vertical direction, and is coaxially provided in the cylindrical casing, and has a large number of liquid passage holes. A rotating basket 1 having a rotating basket 1, a filter medium stretched on the inner peripheral surface of the rotating basket, a rotating shaft connected to an axial center portion on one end face side of the rotating basket, a rotation driving device connected to the rotating shaft, A slurry supply means for supplying slurry into the rotating basket, a cake discharging means for scraping the cake formed on the filter medium and a filtrate discharging means are provided, and the rotating basket is rotated via the rotating shaft by the rotation driving device, In the centrifugal filter for solid-liquid separation of the slurry supplied into the rotating basket by the filter medium by centrifugal force due to rotation, the cylindrical casing has a cylindrical side wall and a lower end surface of the cylinder. The rotating basket is composed of a bottom plate and a cover plate that covers the upper end surface of the cylinder. The rotating basket has an opening at the lower end, an annular weir projecting in the inner radial direction of the lower end opening, and a large number of liquid passage holes. A cylindrical peripheral wall and a top plate that closes an upper end surface of the cylinder, and the rotation shaft passes through a bearing portion provided at a cover plate shaft center portion of the cylindrical casing and is formed on the top plate of the rotation basket. The centrifugal filter is connected to an axial center, and the slurry supply means and the cake discharge means are inserted through the bottom plate of the cylindrical casing through the lower end opening of the rotating basket.

In addition, the second invention is characterized in that the rotary drive device according to the first invention is mounted on a cover plate of a cylindrical casing so as to be directly connected to the rotary shaft.

According to a third aspect of the invention, there is provided a hinge mechanism for connecting the opening and closing of the cover plate to the one end side of the cover plate on the upper outer surface of the cylindrical casing in the first or second aspect of the invention. Is performed.

Since the lower end surface of the rotating basket has a large opening, any cake discharging means can be inserted into the rotating basket, and the scraped cake can be discharged out of the machine by gravity without any obstacles. In addition, by using a cake discharging means that combines a scraping knife and a chute, the entire amount of cake scraped can be reliably recovered, and in order to prevent clogging of the cake discharge port by cake, a cylinder is used during cake scraping. The cake can be discharged in a short time while rotating at a high speed without having to adjust the discharge amount by decelerating the rotation of the basket.

The rotating basket is integrated with the cover plate of the cylindrical casing via a bearing provided at the center of the cover plate, moves up and down as the cover plate opens and closes, and can be moved in and out of the cylindrical casing. Therefore, the outer surface of the rotating basket and the inner surface of the cylindrical casing can be inspected and cleaned in a wide range, and the filter medium stretched on the inner surface of the rotating basket can be easily replaced.

A hinge mechanism connected to one end of the lid plate is provided on the upper outer surface of the cylindrical casing, and the lid plate is opened and closed by this hinge mechanism. Therefore, the lid plate can be opened and closed easily and safely with less power. The basket can be moved in and out, the inner surface of the cylindrical casing and the inner and outer surfaces of the rotating basket can be inspected and cleaned extensively and easily, and the filter medium stretched on the inner surface of the rotating basket can be easily replaced. be able to.

  The objective of improving the efficient and reliable collection and maintenance of the cake in the centrifugal filter was realized by the configuration in which the lower end surface of the rotating basket is the open end.

  FIG. 1 is a sectional view of an essential part of a centrifugal filter according to the present invention, and FIG. 2 is an operation diagram showing an opening operation of the centrifugal filter casing according to the present invention.

Reference numeral 19 denotes a cylindrical side wall 3, a bottom plate 4 that closes the lower end surface of the cylinder, and an openable / closable lid plate 5 that covers the upper end surface of the cylinder, and a cylindrical casing (hereinafter referred to as an axial center). 1 is closed at the upper end surface of the cylindrical peripheral wall 1A having a large number of liquid passage holes, an annular dam plate 1C having an opening at the lower end and protruding in the radial direction inside the lower end opening. A rotating basket (hereinafter simply referred to as a basket) 2 is coaxially provided in the casing, and one end of the top basket 1B passes through the axial center of the lid plate 5 of the casing. A rotary shaft connected to the shaft center and connected to the other end side via a bearing 32 through a rotary drive means 31. 10 is a filter medium stretched on the inner peripheral surface of the basket, 6 is a slurry supply means, and 7 is a cake. Discharging means, 8 is a cover plate 5 of the casing Closing hinge mechanism for connecting one end side of the casing lid plate 5 on the upper end outer surface of the casing side walls 3 to be performed, 12 a filtrate discharge pipe.

The slurry supply means 6 has a nozzle portion for supplying the slurry to be separated toward the filter medium 10 and is erected through the bottom plate of the casing so as to be movable in the vertical direction. The cake discharging means 7 includes a scraping knife having a cutting edge for scraping off the surface of the cake layer 11 formed on the surface of the filter medium 10, and a chute for receiving the scraped cake and discharging it to the outside. The cake layer 11 is provided so as to be movable in the horizontal direction so that a predetermined thickness can be scraped off, so that the scraped cake can be reliably introduced into the chute.

As a mechanism for opening and closing the casing lid plate 5, a hinge mechanism 8 connected to one end side of the casing lid plate 5 is attached to the upper end outer surface of the casing side wall 3, and the hinge mechanism 8 is an air cylinder or a hydraulic cylinder. The piston mechanism 9 is configured to swing. The rotation drive device 31 includes a motor and a rotation shaft that is a drive shaft of the motor. The rotation drive device 31 is mounted on the casing cover plate 5 via a bearing 32 of the rotation shaft 2, and the rotation drive device 31, the cover plate 5, and the like. The basket 1 and the like are integrally movable up and down.
The mechanism for opening and closing the casing cover plate 5 in the present invention may be a structure in which the casing cover plate 5 is simply suspended by a chain block or the like.

Hereinafter, an embodiment of the centrifugal filter of the present invention will be described in more detail together with the operation.
The slurry to be treated is supplied onto the filter medium 10 in the basket 1 rotating at high speed from the slurry supply pipe 6 through the nozzle portion. The supplied slurry is pressed onto the filter medium 10 by the action of centrifugal force, the solid content in the slurry is trapped by the filter medium 10 and accumulated in a layered manner, and the liquid component is drilled in the filter medium 10 and the side wall of the basket 1. After passing through the liquid passage hole thus discharged and discharged into the gap between the basket 1 and the casing 19, it is extracted from the filtrate discharge pipe 12 to the outside of the system.

When the solid-liquid separation operation is performed for a predetermined time, the thickness of the cake layer 11 accumulated on the filter medium reaches an allowable amount, and the cake scraping operation is performed. In the cake scraping operation, the cutting edge of the cake discharging means 7 is brought into contact with the surface of the cake layer 11 without decelerating the rotation of the basket 1, the surface of the cake layer 11 formed on the surface of the filter medium 10 is shaved, and a predetermined thickness is obtained. The cake scraped off leaving the foundation layer is dropped into the chute and collected, and then discharged out of the system through the chute. The cake scraping operation is alternately performed with a solid-liquid separation operation at a predetermined time interval.

When the solid-liquid separation operation and the cake scraping operation are performed for a long time, the filtration efficiency decreases due to clogging of the filter medium 10, and therefore, the internal state is checked, the cleaning operation, and the filter medium replacement are performed. The cleaning operation is performed by removing the fastening members such as bolts, nuts, and clamps that fasten the cover plate 5 of the casing, moving the piston mechanism 9 and swinging the hinge mechanism 8 to raise the cover plate 5. Since the rotary drive device 31, the cover plate 5 and the basket 1 are integrated, the basket 1 is taken out of the casing 19 along with the cover plate 5.

The opening operation of the lid plate 5 by the hinge mechanism 8 may be carried out for inspection and cleaning operations with the basket held in an oblique state as shown in the position A in FIG. 2, but at the position B in FIG. As shown, it can be inspected and cleaned by holding it in a 180 ° inverted state. It should be noted that the replacement of the deteriorated filter medium 10 is preferably performed by reversing 180 ° from the viewpoint of safety and ease, and holding the filter medium 10 on the ground or a relatively low place where workability is good. The washing operation is performed by an appropriate method such as water washing using a hose or the like. Accordingly, the inner and outer surfaces of the basket 1 and the casing 19 can be easily cleaned from the upper side, the side and the lower side, and the filter medium 10 stretched on the inner surface of the basket 1 can be easily replaced.

After the inspection and cleaning operation by opening the cover plate 5 of the casing are completed, the basket 1 is installed in the casing and the opening portion is closed by the cover plate 5. In the operation, the piston mechanism 9 is operated to swing the hinge mechanism 8 so that the cover plate 5 moves downward, and the integrated rotation drive device 31, the cover plate 5, the basket 1, and the like are connected to the cover plate 5. The basket 1 is arranged at a predetermined position in the casing 19 and the cover plate 5 of the casing is fastened with a fastening member.

Each of the above operations is repeated, and the solid-liquid separation of the slurry is performed efficiently.

Centrifugal filter in the chemical industry and food industry, especially suitable for use in the field of manufacturing high-mix low-volume pharmaceuticals and foods that require frequent cleaning inside the casing and replacement of filter cloth, and in biotechnology-related fields It is a centrifugal filter that can be used.

It is principal part sectional drawing of the centrifugal filter of this invention. (Example 1) It is an action | operation figure which shows opening operation | movement of the centrifugal filter casing of this invention. (Example 1) It is sectional drawing of the conventional centrifugal filter. FIG. 4 is a plan view of the rotating basket of FIG. 3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotating basket 1A Rotating basket peripheral wall 1B Rotating basket top plate 1C Rotating basket weir plate 2 Rotating shaft 3 Cylindrical casing side wall 4 Cylindrical casing bottom plate 5 Cylindrical casing lid plate 6 Slurry supply means 7 Cake discharge means 8 Cylindrical casing lid plate Hinge mechanism 9 Cover plate opening / closing cylinder mechanism 10 Filter medium 11 Cake layer 12 Filtrate outlet 19 Cylindrical casing 31 Rotating drive means 32 Bearing 101 Rotating basket 101A Rotating basket peripheral wall 101B Rotating basket bottom plate 101C Rotating basket weir plate 102 Rotating shaft 103 Cylindrical casing Side wall 104 Cylindrical casing lower plate 105 Cylindrical casing upper lid 106 Slurry supply means 107 Cake discharge means 108 Cake discharge pipe 110 Filter medium 111 Cake layer 112 Filtrate discharge pipe 113 Partition 114 Cake discharge port 119 Cylindrical casing 131 Rotation drive device 132 Bearing 133 Belt A Half open operation state of cylindrical casing (Example 1)
B Fully open operation state of cylindrical casing (Example 1)

Claims (3)

A cylindrical casing disposed so that its axis is in the vertical direction, a rotating basket coaxially provided in the cylindrical casing and having a large number of liquid passage holes, and an inner peripheral surface of the rotating basket. A filter medium, a rotary shaft connected to an axial center on one end face side of the rotary basket, a rotary drive device connected to the rotary shaft, a slurry supply means for supplying slurry into the rotary basket, and a filter medium A cake discharging means and a filtrate discharging means for scraping the formed cake are provided, the rotating basket is rotated through the rotating shaft by the rotation driving device, and the slurry supplied into the rotating basket is rotated by a centrifugal force by the rotation. In the centrifugal filter for solid-liquid separation by the filter medium, the cylindrical casing has a cylindrical side wall, a bottom plate that closes the lower end surface of the cylinder, and an opening and closing device that covers the upper end surface of the cylinder. The rotating basket is open at the lower end surface, and closes the annular weir plate protruding in the inner radial direction of the lower end opening, the cylindrical peripheral wall having a large number of liquid passage holes, and the upper end surface of the cylinder. The rotating shaft is connected to the shaft center portion of the top plate of the rotating basket through the bearing portion provided on the cover plate shaft center portion of the cylindrical casing, and the slurry supply means and the cake The centrifugal filter is characterized in that the discharging means passes through the bottom plate of the cylindrical casing and is inserted into the inside from the lower end opening of the rotating basket. The centrifugal filter according to claim 1, wherein the rotary drive device is directly connected to the rotary shaft and is mounted on the cover plate of the cylindrical casing. The centrifugal filter according to claim 1 or 2, wherein a hinge mechanism connected to one end side of the lid plate is provided on an upper end outer surface of the cylindrical casing, and the lid plate is opened and closed by the hinge mechanism.

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