JPS6090018A - Filter element - Google Patents

Abstract

PURPOSE:To assure the filtering accuracy of a filter material and to prevent the lowering in filtering accuracy at the time of reuse of a filter element, by flowing a fluid from the internal space of a filter material main body to the outer surface thereof in the filter element and setting the secondary side of fluid flow to the filter material to the outer surface side of the filter material main body. CONSTITUTION:A fluid is filtered in each filter element 21 by allowing said fluid to pass a filter material from the inner surface side of a filter material main body 22 to the outer surface side thereof through a fluid inflow orifice 25 and allowed to be further flowed into a fluid passage 35 through the piercing hole 36 of a support 32 and exhausted out of the filter apparatus in the direction shown by the arrow B. Because the secondary side of flow to the filter material comes to the outer surface side of the filter element 21 by the flow direction in said filter element 21, the surface of the filter material after detached and washed after used is easily observed from the outside. In addition, if reinforcing materials having a liquid passing property are provided to the upper surface 22b and the lower surface 22C of the filter material main body 22 or either one of both upper and lower surfaces thereof and formed into a structure separable from the filter material main body 22, observation from the outside is further facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a filter element for separating and filtering solid particles or gel-like substances mixed in a fluid.

Prior Art Conventionally, filter elements of various shapes have been used depending on the type of fluid and the type and amount of solid particles or gel-like substances mixed therein. The fluid is a high viscosity substance such as a molten polymer substance, the size of solid particles or gel-like substances to be separated is from several tens of micrometers to several tens of micrometers, and the amount of fluid to be processed is large. In high-performance, large-capacity filtration devices, a filtration system is generally used in which thin disk-shaped so-called leaf disk-shaped filtration elements are stacked and assembled in multiple stages.

The reason for this is that the fluid has a high viscosity and if a large amount is to be filtered,
The pressure loss when fluid passes through a filter medium is generally large, and this pressure difference causes solid particles or gel-like substances to be filtered and separated to slip through the filter medium, making it impossible to perform high-performance filtration and separation. Therefore, it becomes necessary to minimize the pressure loss when passing through the filter medium, in other words, to increase the filtration area of the filter medium.

On the other hand, it is desirable for the filtration device itself to be as small as possible from an economical point of view, so the shape of the filter medium should be determined to have a high level of filtration area per unit area. is the key point. A leaf disk-shaped filtration element is designed from this viewpoint.

This leaf disk-shaped filtration element is, for example,
0-85965, it is generally constructed as shown in FIGS. 1 and 2.

That is, in the figure, 1 indicates the entire filter element, 2 is a hub having a through hole 3, and a porous filter material 4, typically a sintered body or a wire mesh, is attached to the hub 2 to prevent leakage by welding or the like. are combined without. Inside the filter medium 4, a corrosion-resistant reinforcing material 5 such as a stainless wire mesh is provided to prevent the filter medium 4 from deforming due to the filtration pressure when fluid passes through the filter medium 4.
is buried. The fluid to be filtered passes through the porous filter medium 4 from the outside to separate and filter solid substances and gel-like substances, and then passes through the through hole 3 to reach the inside of the hub 2.

The leaf disk-shaped filtration element 1 constructed in this way is normally used in a stacked state within a casing 9 as shown in FIG. For example, each filtration element 1 is stacked and assembled in multiple stages as shown in the figure using a clamping fitting 8 via a presser plate 7 on a strut 6 attached to a mirror plate 12. The inner diameter of the hub 2 is made smaller than the inner diameter of the hub 2 so that the fluid is not blocked, and a fluid passage 11 is provided inside the strut 6, and a through hole 10 is provided in the strut 6 to connect the passage 11 with the outside of the strut 6. The filtration element 1 assembled into the strut 6 is assembled into the casing 9 as shown in FIG. 3, thereby constructing a filtration device.

In the above-mentioned filtration device, the high viscosity fluid containing solid particles or gel-like substances to be separated should be separated from the direction of arrow A in Fig. 3! I! It enters the filtration device, follows the flow path formed by the gap between the clamping fitting 8, the presser plate 7, and the casing 9, and reaches the filtration element 1.

In each filter element 1, as already explained in FIG. 1 and FIG. The gel is separated by filtration. The high viscosity fluid that has passed through each filtration element 1 flows into the gap between the filtration element 1 and the strut 6, then passes through the through hole 10 provided in the strut 6 and the intra-strut passage 11, and then flows out of the filtration device in the direction of arrow B. It is discharged like this. That is, the filtration device constructed by stacking and assembling leaf disk-shaped filtration elements 1 in multiple stages has a large filtration area per unit volume, and has excellent characteristics as a high-performance, large-capacity filtration device for high-viscosity fluids. It is said that

However, it has been found that such conventional filtering devices and filtering elements have the following problems.

First, the first problem is that when the above-mentioned conventional filtration device reaches a certain capacity, no matter how many layers of leaf disc-shaped filtration elements are increased, the amount of solid particles and gel particles that reach the desired level is reduced. It turns out that you can't separate things.

That is, the filtration area of the filter medium is determined by maintaining a pressure drop difference sufficient to prevent solid particles or gel-like substances from slipping through, and the number of leaf disk-shaped filtration elements determined from this filtration area is laminated and used. Also, there is a problem in that solid particles or gel-like substances are not separated by the filter medium as intended and remain in the high viscosity fluid that has passed through the filter device.

In order to solve this problem, the present inventors actively investigated flow analysis of the conventionally used leaf disc-shaped filtration element, and as a result, the inventors of the present invention have developed a filtration system incorporating a conventional leaf disc-shaped filtration element. It has been found that the device has a fatal drawback in that, since the high viscosity fluid flows from the outside to the inside of the filter element, the stress due to the pressure drop difference all leads to the compression of the filter media.

As explained in FIGS. 1 and 2, the filter element has a reinforcing material to prevent the filter material from being deformed due to the pressure drop difference, so the filter material itself will not be damaged and the filtering function of the filter material itself will be maintained. Although there is no performance deterioration,
When a high viscosity fluid flows through a flow path consisting of the inner periphery of the casing 9, the filtration element 1, and the outer periphery of the holding plate 7 of the filtration device explained in FIG. This will act as a force that compresses 1. therefore,
If this compressing force becomes larger than the tightening force by the clamping fittings etc. when stacking the filter elements 1 in multiple stages and assembling them into the strut 6, light heat can be A gap is created somewhere in the stacked filter elements 1, and through this gap, high viscosity fluid that does not pass through the filter medium flows into the interior of the strut 6.

This phenomenon is a phenomenon that occurs when high-viscosity fluid passes through a filtration device, and even if the filtration device is used and disassembled, it will elastically restore itself and almost completely return to its original state, making it appear as if the filtration capacity has decreased. It can only be observed as a state. It is clear from the above explanation that this phenomenon becomes more obvious as the number of filtration elements 1 increases, and in order to solve this problem, the inventors have proposed that the assembly and tightening of the filtration elements 1 to the struts should be performed without increasing the force. After much consideration, it was concluded that there is a limit to the shape of the hub 2 of the filtration element 1, and that it would be difficult to increase the strength of the hub 2 without reducing the filtration area of the filter medium of the filtration element 1.

Furthermore, the gap between the flow path formed by the inner periphery of the casing 9 and the outer periphery of the filter element 1 and the presser plate 7 explained in FIG. 3 is widened,
We have considered ways to reduce pressure loss when high-viscosity fluid flows, but the residence time of high-viscosity fluid in the filtration device increases, and there is a great possibility that the physical properties of high-viscosity fluid may change due to this. Not the preferred method. In other words, high viscosity fluids such as polymers are generally filtered at high temperatures, and the longer the residence time at high temperatures, the more decomposition reactions will be induced, and in the worst case, gel formation will occur. It even reaches the point.

Further, a certain relationship is established between the inner circumference of the casing 9, the gap between the outer circumference of the filter element 1, and the internal channel 11 of the strut 6 in order to uniformly pass the high-viscosity fluid to each of the multi-stage filter elements 1. Increasing the former gap increases the outer diameter of the struts 6 and the inner diameter of the hub 2 of the filter element 1. If the outer diameter of the filter medium is suppressed, the filtration area of the filter medium decreases or the number of laminated stages of the filter medium increases. It was found that this increase led to long filtration, which was not a good idea.

Next, as a second problem, it has been found that the conventional filter element 1 described above is structurally disadvantageous when cleaning for reuse.

That is, in a filtration device in which the filtration elements 1 are stacked and assembled in multiple stages, as the cumulative flow rate of fluid passing through the filtration elements 1 increases, the outer surface of the filter medium 4 becomes clogged due to separated and filtered foreign matter. The primary side pressure of the passing fluid gradually increases and reaches the allowable upper limit pressure. Normally, the filter elements 1 are replaced all at once when this upper limit pressure is reached. These used filter elements 1 are cleaned for reuse, and the cleaning fluid and process are appropriately selected depending on the type of fluid to be applied, the amount of trapped foreign matter, and the like. In cleaning, it is desired that the interior of the filter element 1 be completely cleaned in order to maintain high filtration accuracy in response to product quality requirements that have become stricter in recent years.

However, with the structure of the conventional filter element 1, it is difficult to completely clean the inside thereof and to check whether the cleaning state is not incomplete. In other words, in the conventional filter element 1, the fluid passes from the outer surface to the inner surface of the filter medium 4, so the inner surface of the filter medium 4 becomes the secondary surface for the fluid flow. Since the next surface is surrounded by the filter medium 4, its cleaning state cannot be confirmed. Further, cleaning is performed by passing a chemical solution, water, etc., but since the chemical solution etc. become dirty due to cleaning, the inner surface of the filter medium 4 may be contaminated by the dirty chemical solution etc. If foreign substances remain on the inner surface of the filter element 4 or in the internal space surrounded by the filter element 4 or are contaminated during the cleaning process, these foreign substances will flow out when the filter element 1 is reused, resulting in poor filtration accuracy. This decreases accordingly, and causes trouble in subsequent processes, leading to a decrease in the operating rate of the equipment and a decrease in the product acceptance rate.

OBJECTS OF THE INVENTION In order to solve the first and second problems in the conventional device, the present invention provides a filter medium selected to prevent the phenomenon in which fluid flows without passing through the filter medium within the filtration device. It is possible to maintain the specified filtration accuracy of
To provide a filtration element in which the degree of cleaning of the surface of a filter medium on the secondary side through which filtered fluid flows out can be easily checked visually, and when foreign matter remains on the surface of the secondary side filter medium, it can be easily rewashed. purpose.

Structure and operation of the invention The filtration element of the present invention that meets this objective has an annular member body having an internal space with an open outer circumferential surface and whose upper surface, lower surface, and most of the inner circumferential surface are made of a filter medium. , an annular support member integrally joined to the filter medium body with the inner circumferential surface meeting the outer circumferential surface of the member main body, and provided with a fluid inflow hole penetrating between the inner circumferential surface and the outer circumferential surface; and a filter medium. It consists of a reinforcing material having liquid permeability disposed on either the upper surface, the lower surface, or both upper and lower surfaces of the main body.

In the filtration element configured in this manner, fluid is introduced from the outer circumferential surface of the filtration element through the fluid inflow hole into the internal space of the filter body, and is filtered by passing through the filter medium from the inner surface to the outer surface.

Since the flow direction of the fluid is from the inner surface of the filter medium to the outer surface, the force acting on the filter medium due to the pressure loss when passing through the filter medium acts in the direction of making each filter element closer to each other, and the fastening force between the filter elements increases. will be increased. Therefore, the conventional problem of compressive force applied to the filtration elements creating gaps between the filtration elements and causing fluid to flow without passing through the members is prevented, and all the fluid that flows in passes through the filter medium. The filtration accuracy of the selected filter material is reliably demonstrated.

In addition, since the secondary side of the fluid flow to the filter medium is the outer surface of the filter medium, the state of the secondary filter medium surface after cleaning can be easily observed, and if the observation results show that the cleaning is insufficient, the filtration Easily re-cleaned from the external side of the element. Re-washing regenerates the clean surface of the filter medium and prevents a decrease in filtration accuracy when the filter element is reused.

EXAMPLES Below, preferred examples of the filter element of the present invention will be described with reference to the drawings.

4 and 5 show a filter element according to an embodiment of the present invention, and in the figures, 21 indicates the entire filter element. 22 is a filter medium main body, and the filter medium main body 22 has an outer peripheral surface 2.
2a has an open internal space 23, and most of the upper surface 22b1, the lower surface 22c, and the inner circumferential surface 22d are made of an annular member formed of a filter medium. The filter medium is made of a porous filter medium such as a sintered body or a wire mesh.

An annular support member 24 is provided on the outer circumferential surface 22a side of the filter medium main body 22, and the outer circumferential surface 22a and the inner circumferential surface 24a are joined in a state where they meet, and the joint is made by welding or the like so that there is no leakage. It is being done. An appropriate number of fluid inflow holes 25 are provided in the support member 24 over its entire annular circumference, penetrating between the inner circumferential surface 24a and the outer circumferential surface 24b. The fluid inflow hole 25 communicates the internal space 23 surrounded by the member main body 22 and the outer circumferential space of the support member 24 .

An annular reinforcing member 26 is provided on the upper surface 22b of the filter medium main body 22 so as to cover the entire upper surface 22b. Reinforcement material 2
6 is made of a corrosion-resistant wire mesh made of stainless steel or the like in this embodiment, but as shown in FIGS. 6 and 7, there are many holes 27 and radial passages 28 communicating with the holes 27. The perforated plate 29 may have any structure as long as it has liquid permeability.

Further, the reinforcing material 26 may be integrally joined to the filter medium main body 22, but desirably, it is preferable that the reinforcing material 26 is easily separable from the filter medium main body 22. Furthermore, in this embodiment, the reinforcing material 26 is provided on the upper surface 22b side of the filter medium main body 22, but if necessary, as shown in FIG. There may be, and
As shown in FIG. 9, the structure may be such that it is provided only on the lower surface 22c side.

In addition, although the illustrations have been simplified, in order to facilitate handling,
And in order to increase the strength against deformation of the filter medium main body 22,
A member having liquid permeability similar to the reinforcing material 26 may be embedded in the internal space 23 of the filter medium main body 22 .

The filtration element 21 configured in this manner is normally used by being assembled in a stacked manner within a casing 30, as shown in FIG. The filtration element 21 is fastened and fixed to a support 32 attached to a mirror plate 31 with a clamping fitting 34 via a presser plate 33, and is stacked and assembled in multiple stages. The outer diameter of the strut 32 is made smaller than the inner diameter of the filter element 21, and the filter medium main body 22 of the filter element 21 is fitted into the strut 32. and,
The strut 32 is provided with an internal fluid passage 35 and a through hole 36 . In this way, the filtration device is constructed by stacking and assembling the filtration elements 21 in multiple stages within the casing 30.

Next, the operation of the filter element configured as described above will be described below.

First, regarding the flow of fluid within the filtration device, in FIG. 10, a high viscosity fluid containing solid particles or gel-like substances to be separated enters the filtration device from the direction of arrow A in the figure, and enters the casing 30 inside the filtration device. While flowing along, the water is supplied to each of the filter elements 21 stacked in multiple stages. In each filter element 21, as shown by the arrow in FIG. The liquid flows through the through hole 36 of the column 32 into the fluid passage 35, and is discharged out of the filtration device in the direction of arrow B. The flow path of this fluid is that it flows along the inner surface of the casing 30 and passes through the filtration element 21 before exiting through the intra-branch fluid passageway 35.
This is the same as the conventional device shown in FIG. 3, and therefore, even if the filtration element 21 according to the present invention is used, there is no need to change the design of the other members of the filtration device or the devices before and after the filtration device.

Next, regarding each i11"i4 element 21, since the flow direction of the fluid is from the inner surface to the outer surface of the filter medium main body 22, the force acting on the filter medium due to the pressure difference between the inner and outer surfaces due to pressure loss when passing through the filter medium is It is applied in the direction of opening the main body 22, that is, in the direction of making the filter elements 21 more compressed.Therefore, the fastening force between the filter elements 21 is increased rather than decreased, and the gap between the filter elements 21, which was a problem in the past, is reduced. The phenomenon that occurs is prevented, and the fluid reliably flows into the filter medium body 22.
passes through the filter medium. By ensuring that all fluid passes through the filter media body 22, the filtration accuracy of the selected filter media is guaranteed.

Furthermore, since the support member 24 of the filter element 21 is disposed on the outer peripheral side of the filter medium body 22 compared to the conventional filter element shown in FIGS. 1 and 2, the filter element 21 can be stacked in multiple stages. The pressure receiving area for the clamping force by the clamping fittings 34 etc. when assembling can be increased, making it possible to assemble with a larger clamping force, and preventing fluid leakage between the filtration elements 21 more reliably. Ru.

Further, due to the flow direction in the filter element 21, the secondary side of the flow to the filter medium is the outer surface side of the filter medium main body 22, so the surface condition of the filter medium after being removed and washed after use can be easily observed from the outside. If the reinforcing material 26 is configured to be separable from the filter medium main body 22, observation from the outside will be made easier. Therefore, it is easy to determine whether the cleaning is complete and whether the filter medium is cross-contaminated by the cleaning fluid or the like. If foreign matter remains on the surface of the secondary filter medium, it can be easily rewashed while checking since it is on the outer surface, ensuring a clean surface of the filter medium when the filter element 21 is reused. to ensure filtration viscosity.

As described in detail, the filtration element of the present invention provides the following various effects.

First, since the flow direction of the fluid in the filtration element is from the internal space of the filter body to the outer surface of the filter body, the direction of the force acting on the filter medium due to the pressure difference due to the pressure loss when passing through the filter medium is determined between the stacked filter elements. This allows the filtration elements to be more compressed, preventing the conventional problem of creating gaps between each filter element, ensuring that all the fluid passes through the filter, and improving the filtration accuracy of the selected filter. The effect is that it can be guaranteed.

In addition, since the secondary side of the fluid flow to the filter media is placed on the outer surface of the filter media body, the cleaning condition of the secondary filter media surface can be easily observed from the outside, and if foreign matter remains, it can be easily reused. In addition to being able to be cleaned, it is also possible to prevent a decrease in filtration accuracy upon reuse of the filtration element, thereby ensuring the quality of the filtered fluid.

[Brief explanation of drawings]

Figure 1 is a plan view showing a part of a conventional filtration element in cross section, Figure 2 is a longitudinal sectional view of the device in Figure 1 taken along the line ■-■, and Figure M3 is a multi-stage configuration of the device in Figure 1. FIG. 4 is a plan view showing a part of a filtration element in cross section according to an embodiment of the present invention, and FIG. 5 is a v-v line of the device shown in FIG. 4. FIG. 6 is a plan view of a reinforcing material according to another embodiment, and FIG. 7 is a partial sectional view of the device shown in FIG. 6 taken along the line ■-■. FIG. 8 is a longitudinal cross-sectional view of a filtering element according to another embodiment in which the arrangement of reinforcing materials is changed; FIG. 9 is a longitudinal cross-sectional view of a filtering element according to another embodiment in which the arrangement of reinforcing materials is further changed; FIG. 10 is a longitudinal sectional view of a filtration device in which the devices shown in FIG. 4 are stacked in multiple stages. 21...Filtering element 22...Filtering medium body 22a...Outer peripheral surface 22I) -...Upper surface of filtering medium body 22c...Lower surface of filtering medium main body 22d...Inner circumferential surface 23 of filter medium body...Inner space 24...Support member 24a...Inner circumferential surface 24b of support member... - Outer peripheral surface of support member 25... Fluid inflow hole 26... Reinforcement material 30... Casing 32... Support column 35... Fluid passage Figure 1 Figure 2 Figure 3 This is life Figure 8 Figure 9

Claims (1)

[Claims] (1) An annular filter medium body having an inner space with an open outer circumferential surface and a top surface, a bottom surface, and most of the inner circumferential surface formed of filter medium, and the inner circumferential surface meeting the outer circumferential surface of the filter medium main body. an annular support member that is integrally joined to the filter medium main body in a state where the filter medium main body is in the same state as the filter medium main body, and is provided with a fluid inflow hole that penetrates between the inner peripheral surface and the outer peripheral surface; A filtration element comprising: a reinforcing material having liquid permeability disposed on said surface;