JPH0719536Y2 - Rotary filtration device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a rotary filtration device for separating and concentrating bacterial cells and the like using a microfiltration membrane or an ultrafiltration membrane.

[Conventional technology]

In the filtration method of pressurizing or vacuum-filtering a stock solution containing suspended bacterial cells using a microfiltration membrane or an ultrafiltration membrane, fine particles or gelatinous substances contained in the stock solution as the filtration progresses. Etc. are captured on the surface of the filtration membrane, and an adhesion layer is formed on the filtration surface.

Since the adhesion layer composed of these fine particles and a high-viscosity substance such as gelatin has a high filter compressibility, the filter surface is rapidly clogged with the progress of the filter to increase the filter resistance.

A rotating filtration device, that is, a plurality of filtration devices equipped with hollow small chambers inside, is a typical device that suppresses the formation of an adhering layer on the filtration surface to prevent a decrease in filtration efficiency and continuously filters. It is provided on the shaft in a concentric manner with a gap in series, and these are integrally rotated to give a centrifugal force to the particles trapped on the surface of these filter elements to eliminate them in the outer peripheral direction, while There is a filtering device that suppresses the formation of an adhered layer by generating a turbulent flow or a vortex in the stock solution due to a relative speed difference with the filtering element.

However, in these rotary filtration devices, simply rotating the plurality of filtration elements integrally causes a so-called co-rotation phenomenon in which the undiluted solution between these filtration elements flows together in the same direction as the filtration elements, resulting in a filtration surface. Since the intended purpose of suppressing the formation of the adhesion layer cannot be achieved, various measures have been added to the structure for preventing the occurrence of this accompanying flow, and many proposals have been made.

As these conventional rotary filtration devices, for example, a fixed filtration element is arranged between a plurality of rotary filtration elements mounted on a hollow rotary shaft (Japanese Patent Laid-Open No. 47-23949), and the outer peripheral portion is brought into contact with the filtration tank wall. An annular filter element equipped with a rotating back-feeding blade and provided with a circulation portion near the hollow rotation shaft and a filtration element having a circulation gap in the outer peripheral portion are alternately attached to the rotation shaft while scraping between the filtration elements. A blade that is freely rotatable (Japanese Patent Laid-Open No. 48-8
No. 7473), between the plurality of filtration elements mounted on the hollow rotating shaft, and in the hollow portion provided inside these filtration elements, one or a plurality of flows extending in the direction orthogonal to the rotation direction of the filtration elements. A control element (Japanese Patent Laid-Open No. 50-69657) is known.

Further, in order to remove the adhering layer that is inevitably formed as the filtration progresses, a brush is attached at a fixed position on the wall side of the filtration tank so as to be able to advance and retreat in the radial direction, and the brush is attached to the rotary shaft. There is one that is inserted between the filter elements to remove the adhesion layer on the surface of each filter element.

[Problems to be solved by the device]

However, although the above conventional rotary filtration device can suppress the formation of an adhesion layer on the surface of the filtration element, the rotary filtration element and the fixed filtration element, the scraping blade, the flow control body, etc. are alternately arranged, and as few as possible. Since it needs to be installed in a gap, and its structure becomes extremely complicated and precise, there is a problem that a complicated procedure is required for its assembly and disassembly.

Further, in order to remove the adhesion layer that is inevitably formed as the filtration progresses, when a brush is provided at a fixed position on the filtration tank wall side, between the brush inserted from the filtration tank wall side and each rotary filtration element, It is required that the relative positions of the above-mentioned filters are accurately assembled, and that each rotary filtration element is not distorted. Further, it is necessary to provide a brush storage space on the filter tank side, which causes a problem that the outer shell becomes large.

In view of the problems in the above conventional device, the present invention can suppress the formation of the adhering layer on the surface of the filter element with a simple structure, and easily and reliably remove the adhering layer formed on the surface of the filter element. The purpose of the present invention is to provide a rotary filtration device that can be used.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the rotary filtration device of the present invention is provided with a rotary shaft having a central hole in communication with filtration liquid removing means in a filtration tank configured to continuously feed the raw liquid. Along with this, a plurality of disk-shaped filter elements having hollow small chambers inside are mounted concentrically on the rotary shaft with a gap that allows free passage of liquid, and the small chambers of these filter elements and the central hole of the rotary shaft are connected. In a rotary filtration device which is in fluid communication with each other, a stock solution through-hole for axially passing the stock solution is provided near the center of rotation of each of the filter elements, and one end of each of the filter elements is provided between the filter elements. Is rotatably supported individually on the rotary shaft, and a rod-shaped brush having the other end projecting outward from the outer periphery of the filter element is arranged in the radial direction, and the inner peripheral surface of the filter tank and the outer periphery of the filter element are arranged. A bar shape that can be rotated and retracted in the space of It is provided with a stopper of the brush.

The rod-shaped brush may have a curved shape protruding in the rotation direction of the filter element.

In addition, stoppers of rod-shaped brushes may be provided at a plurality of positions having different angular phases at equal angles in the rotation direction of the filter element.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a front sectional view showing a main part of a rotary filtration device according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line II-II of FIG.

In FIG. 1 and FIG. 2, (1) is a filtration tank, and this filtration tank (1) is provided with an inlet pipe (1a) communicating with a supply means of a stock solution (not shown) and a concentrated filtration solution (not shown). A closed pressure vessel provided with an outlet pipe (1b) communicating with a collection / circulation means.

(2) is a hollow rotary shaft, and this hollow rotary shaft (2)
Is rotatably and watertightly inserted into the filtration tank (1) via the shaft sealing device (7), and is connected to the transmission and bearing device (8) at the end outside the filtration tank (1). A filtrate outlet pipe that is driven and rotated by an electric motor (9) connected to the transmission and bearing device (8) and has a shaft end outside the filter tank (1) that communicates with a filtrate recovery means (not shown). It has (2a).

(3) is a filter element, and this filter element (3) has a disk shape with a hollow small chamber inside, and is provided with a stock solution throughflow port (3a) near the center of rotation. The hollow rotary shaft (2) is connected to the hollow rotary shaft (2) through three filter pipes (6) that are in fluid communication with the central hole of the hollow rotary shaft (2) and are arranged at equal angles in the circumferential direction, and Hollow rotating shaft (2)
A plurality of them are arranged in series at right angles to each other at equal intervals in the axial direction, and are each rotatable integrally with the hollow rotary shaft (2).

(4) is a rod-shaped brush, and this rod-shaped brush (4)
Is provided on the main body (4a) in which brush bristles are evenly and densely planted on the outer peripheral portion of the rod body, and on the main portion of the main body (4a),
An annular rotating part (4b) rotatably mounted on the outer circumference between the respective filtration elements (3) of the hollow rotating shaft (2), and a main body part (4a).
And a stopped rod portion (4c) in which brush bristles on the side opposite to the annular rotation portion (4b) are not planted, and the stopped rod portion (4c) is provided between each of the filtering elements (3). The filter element (3) is arranged radially in such a manner that the tip of the bristles of the main body (4a) is brought into light contact with the side surface of the filter element (3) while protruding outward from the outer periphery of the filter element (3).

(5) is a stopper, and this stopper (5)
Is provided with a rotating shaft (5a) and a band-plate-shaped stop plate (5b) provided on the outer periphery of the rotating shaft (5a) so as to project in the radial direction and be long in the axial direction. In the space between the inner peripheral surface of the filter tank (1) and the outer peripheral surface of the filter element (3), it is rotatably and watertightly inserted in parallel with the hollow rotary shaft (2) via a shaft sealing device (10). The end of the rotating shaft (5a) outside the filtration tank (1) is connected to a rotating means (not shown). Then, when the stop plate (5b) is positioned and rotated in the inner diameter direction toward the hollow rotary shaft (2), the stop plate (5b) contacts the stopped rod portion (4c) of the rod brush (4). When the rod-shaped brush (4) is brought into contact with it and the rotation of the rod-shaped brush (4) is stopped, and when the rod-shaped brush (4) is rotated and retracted in the other direction, the rod-shaped brush (4) is allowed to freely rotate. That is, the stopper (5) arbitrarily stops the rod-shaped brush (4) at its installation position by its rotation.

In the filtration by the rotary filtration device of the present embodiment having the above-mentioned configuration, the undiluted solution was supplied under pressure from the inlet pipe (1a) into the filtration tank (1) and filtered by each rotating filtration element (2). The filtrate is a filtrate pipe (6) and a hollow rotating shaft (2).
The stock solution, which is taken out of the system from the filtrate outlet pipe (2a) through the central hole of the above, is concentrated on the other hand in the filtration tank (1) by filtration and is appropriately discharged from the outlet pipe (1b).

Further, the undiluted solution in contact with the surface of the rotating filtration element (3) receives the rotational force of the filtration element (3) according to its viscosity, flows along with the rotation direction of the filtration element (3), and is rotated by the rotation. It receives centrifugal force and flows in the outer peripheral direction of the filter element (3), that is, in the radial direction of rotation.

Then, the stock solution flowing in the outer peripheral direction of the filtration element (3) flows along the wall surface of the filtration tank (1) and is made to flow from both side wall surface portions toward the center of rotation of the filtration element (3), and each filtration is performed. Each filter element (3) is moved from the center of each filter element (3) via the undiluted solution throughflow port (3a) provided near the center of rotation of the element (3).
Between the filter elements (3), the flow in the rotational direction accompanying the rotation of the filter element (3) described above and the flow in the radial direction due to the centrifugal force of the rotation. It becomes a composite flow and is made to flow in the outer peripheral direction while forming a spiral flow.

Due to this flow of the stock solution, the suspended fine particles in the stock solution which are to be attached to the surface of the filtration element (3) are pushed in the outer diameter direction, and formation of an adhesion layer on the surface of the filtration element (3) is suppressed. It

In the above-mentioned filtration, when the stopper plate (5b) of the stopper (5) is pivotally retracted and the rod-shaped brushes (4) are allowed to freely rotate, each rod-shaped brush (4) rotates the filtration element (3) and the stock solution. The rod-shaped brushes (4) are arranged in the radial direction, so that the stock solution and suspended fine particles in the stock solution are prevented from moving in the radial direction. Never.

Further, when the adhesion layer of fine particles is formed on the surface of the filtration element (3) as the filtration progresses and the filtration resistance increases, the stopper (5) is rotated while continuing the rotation of the filtration element (3). Then, the stop plate (5b) is brought into contact with the stopped rod portion (4c) of the rod-shaped brush (4) to stop the rotation of the rod-shaped brush (4), so that the filter element (3) and the rod-shaped brush (4). 2) relative to the filter element (3), the adhesion layer of the fine particles formed on the surface of each filtration element (3) can be easily peeled off and re-suspended in the stock solution in the filtration tank (1).

In addition, the stock solution with an increased concentration of fine particles is
It is discharged from b) and removed from the system.

As described above, the rotary filtration apparatus of the present embodiment has a simple structure that is easy to implement in which each filter element is provided with a stock solution throughflow port, and the stock solution being filtered is caused to flow in the radial direction of rotation, and each filter is filtered. It is possible to suppress the formation of an adhesion layer on the surface of the element, and to provide a rod-shaped brush rotatably and arbitrarily stoppable between each of the filter elements. Without sacrificing efficiency
The adhering layer unavoidably formed on the surface of the filter element can be easily and surely removed, and thus stable filtration can be continued for a long period of time.

On the other hand, as described above, the undiluted solution between the filtration elements (3) is divided into a flow in the rotation direction accompanying the rotation of the filtration element (3) and a flow in the rotation radius direction due to the centrifugal force of the rotation. Since it becomes a combined flow and is made to flow in the outer peripheral direction of the filter element (3) while forming a swirl-like flow, the rod-shaped brush (34) is made to swirl this stock solution as in the example shown in FIG. By bending the filter element so as to have a curved shape protruding in the rotation direction A so as to follow the flow, the resistance to the flow of the stock solution between the filter elements in the outer peripheral direction can be made smaller.

Further, when the stoppers (45) of the rod-shaped brushes (4) are provided at a plurality of positions where the angle phases are equiangularly different in the rotation direction of the filter element (3) as in the example shown in FIG. (4) Each can be dispersed in the rotation direction and stopped, and the resistance to each rotating filtration element (3) can be dispersed in the rotation direction and equalized.

[Effect of device]

As described above, the rotary filtration device of the present invention allows the stock solution being filtered to flow in the radial direction of rotation by a simple structure that is easy to implement, in which the stock solution throughflow port is provided near the center of rotation of each filter element. It is possible to suppress the formation of an adhesion layer on the surface of each filter element, and to provide a rod-shaped brush between each filter element so that it can rotate and can be stopped arbitrarily. It is possible to easily and surely remove the adhering layer of fine particles that is inevitably formed on the surface of the filter element without lowering the filtration efficiency,
Therefore, stable filtration can be continued for a long period of time.

[Brief description of drawings]

FIG. 1 is a front sectional view showing a main part of a rotary filtration device according to an embodiment of the present invention. FIG. 2 is a sectional view taken along line II-II of FIG. 3 to 4 are explanatory views of other embodiments of the present invention. (1) …… Filter tank (2) …… Hollow rotating shaft (3) …… Filter element (4) …… Rod brush (5) …… Stopper

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B01D 33/58

Claims (3)

[Scope of utility model registration request] 1. A rotary shaft having a central hole communicating with a means for taking out the filtrate is provided in a filtration tank configured to continuously feed the stock solution, and a hollow small chamber is internally provided on the rotary shaft. In a rotary filtration device comprising a plurality of disc-shaped filter elements which are concentrically arranged with a liquid-flowing free space therebetween, and the small chambers of these filter elements and a central hole of a rotary shaft are communicated in a liquid-flowable manner. , While providing a stock solution through hole for axially flowing the stock solution near the center of rotation of each of the filtration elements,
Between each of the filtering elements, one end is rotatably supported individually on the rotary shaft, and the other end is protruded from the outer circumference of the filtering element so that a rod-shaped brush is radially arranged. In addition, the rotary filtration device is characterized in that a stopper of a rod-shaped brush that can be rotated and retracted is provided in a space between the inner peripheral surface of the filtration tank and the outer periphery of the filtration element. 2. The rotary filtration device according to claim 1, wherein the rod-shaped brush has a curved shape protruding in the rotation direction of the filtration element. 3. The rotary filtration device according to claim 1 or 2, wherein stoppers of the rod-shaped brush are provided at a plurality of positions having different angular phases at equal angles in the rotational direction of the filtering element. .