JPH0611370B2 - Filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a filtration having an average pore size smaller than the average pore size of a porous tubular substrate on at least one of the inner and outer surfaces thereof. The present invention relates to a filter in which a plurality of ceramic cylindrical filters each having a layer are arranged in parallel in a longitudinal direction thereof.

[Prior art]

This type of filter is used in many fields such as microfiltration and ultrafiltration. In this filter, each filter is assembled as shown in FIG. FIG. 8 partially shows a module which is a filter structure, and each filter 1 is supported at both ends thereof through a cap-shaped seal member 2 which is a stepped cylinder shown in FIG. It is fitted in the stepped hole 3a of the plate 3 and arranged in parallel with each other,
The filter plates 1 are assembled by tightening and fixing the support plates 3 to the respective ends of a plurality of tie rods 4 arranged in parallel with the filter plates 1 between the support plates 3.

[Problems to be solved by the invention]

By the way, in such a filter, each filter 1 and the support plate 3 are attached to each seal member 2 by tightening each filter 1 from both ends thereof with each support plate 3.
The space is hermetically sealed, and when each filter 1 is thin and long, a problem in strength occurs and the above-mentioned assembling means cannot be used.

Further, such a filter is often used in the fields of food and medicine, but in this case, it is required to sterilize each filter 1 periodically, and steam heating and cooling are repeatedly performed. Therefore, creep progresses in each seal member 2 to cause a seal defect, and there is a concern that a leak may occur between each filter 1 and each support plate 3.

Further, in such a filter, when the length of each filter 1 has a variation of a predetermined range or more, each sealing member 2
Since there is not enough tightening margin to prevent leakage,
Strict dimensional control is required for each filter 1.

Therefore, an object of the present invention is to eliminate the above-mentioned problems by removing the above-mentioned assembling means of each filter and assembling so as to be in a free state in the longitudinal direction.

[Means for solving problems]

The filter according to the present invention is made of a plurality of ceramics provided with a filter layer having an average pore diameter smaller than the average pore diameter of the same substrate on at least one surface of the inner and outer peripheries of the porous tubular substrate. A cylindrical filter, a pair of first support plates through which both ends of each of the filters are inserted and support the filters in parallel, and stepped holes into which both ends of the filters are fitted, respectively. A pair of second support plates that are assembled to the outside of each first support plate and support the respective filters together with the same plate are provided, and the both plates and the respective second plates are provided between the both plates on the outer periphery of the end of each of the filters. An annular sealing member for sealing between the three members of the filter is interposed, and the end surface of the base material and the outer peripheral surface of the end portion of each filter are plugged.

Thus, in the filter according to the present invention, when a tubular filter having a filtration layer on the inner peripheral surface of the tubular base material is used as each filter, at least the end face of the base material and the outer periphery of the end portion of each filter are used. It is necessary to seal from the tip of the surface to the contact part of the seal member, and when using a cylindrical filter having a filtration layer on the outer peripheral surface or both the inner and outer peripheral surfaces of the base material, at least in each filter It is necessary to seal the end face of the base material.

The base material constituting the filter is mainly composed of usual ceramic raw materials such as alumina, silica, silica-alumina, mullite, cordierite, and zirconia. For example, fine particles of these raw materials, an appropriate binder for the fine powder, a plasticizer, etc. Extrusion molding of a mixture obtained by kneading with the molding aid of
A porous body formed by casting and the like into a hollow cylindrical body, a monolithic honeycomb body having a large number of through holes in the longitudinal direction, and a honeycomb-shaped cylindrical body and fired. Further, the filtration layer constituting the filter is a porous body having an average pore diameter smaller than the average pore diameter of the base material, and the suspension of fine particles constituting the filtration layer on the inner peripheral surface, outer peripheral surface or both inner and outer peripheral surfaces of the base material. The turbid slurry is formed by means such as adhesion by filtration with a pressure difference applied, adhesion of gel film by sol-gel method, high pressure compression of fine powder, adhesion of porous glass and the like.

Examples of materials used for plugging include glazes, inorganic materials such as alumina-based ceramic bonds, suspensions of silicon resins and fluorine resins, and organic materials such as epoxy resins.

[Operation and effect of invention]

In the filter according to the present invention, the liquid to be treated and the gas to be treated are supplied from one end of each filter into the inner hole and filtered through the filter layer, and each filter is provided on the inner peripheral surface of the base material. If the base material has an end face and an outer peripheral surface of the end portion, the outer peripheral surface of the base material is sealed, so that an annular seal member interposed between the support plates at the outer peripheral surface of the base material ensures a reliable seal between these three members. At the same time, the so-called bypass flow is prevented from entering the base material from the end surface and the outer peripheral surface of the end portion of each filter and flowing out to the outer peripheral surface of the base material without passing through the filtration layer. When each filter has a filtration layer on the outer peripheral surface of the base material, at least the end surface of the base material is plugged and the outer peripheral surface of the base material has a smaller average pore diameter than the base material. Due to the existence of the layer, the above-mentioned sealing member reliably seals each filter and both supporting plates from each other, and prevents the generation of a bypass flow from the end face of the base material of each filter into the base material. To be done.

Therefore, if such a sealing means is adopted, it is not necessary to clamp each filter from both ends thereof by the support plates to seal, and the space between each end face of each filter and the end face of the stepped portion of the stepped hole of the second support plate. It is possible to secure an arbitrary gap. Therefore, even when each filter is thin and long, the strength does not pose a problem during assembly, and even if the length of each filter varies more than a predetermined range, such variation is caused by the above gap. Since it is well absorbed and does not participate in the seal,
Strict dimensional control of each filter is not required. Further, as the seal member, an annular seal member may be used, and a cap-shaped seal member as in the conventional case is not required. Therefore, even if steam heating and cooling are repeatedly performed, the occurrence of seal failure due to progress of creep is prevented. It

〔Example〕

(1) Filter The filter shown in FIG. 1 is a filter according to an embodiment of the present invention. In the filter, the module 10 as a filter structure is housed in a cylindrical casing 20.

As shown in FIGS. 2 to 4, the module 10 includes a large number of cylindrical filters 11, a pair of first support plates 12 and second support plates 13, and a plurality of tie rods 1.
4 and tightening bolts 15 and a large number of O-rings 16. The filter 11 is a ceramic cylinder having a filtration layer 11b on the inner peripheral surface of the base material 11a.
Each end surface 11c and each end outer peripheral surface 11d are plugged with glaze or the like. The first support plate 12 is provided with a circular recess 12a having a predetermined depth on the outer end face side, and the disc portion 12b has a large number of first through holes 12c corresponding to the filter 11 and a number corresponding to the tie rod 14. And a plurality of first through holes 12d. Each first support plate 1
2, the ends of the filters 11 are inserted into the first through holes 12c and the ends of the tie rods 14 are fitted into the second through holes 12d through the O-rings 17, respectively. Each filter 11 is supported by being held at a predetermined interval by. The second support plate 13 has a disc shape and includes a large number of first stepped through holes 13 a corresponding to the filter 11 and a second stepped through holes 13 b corresponding to the tie rods 14. In each second support plate 13, in a state of being fitted into the circular recess 12a of each first support plate 12, it is inserted into each second stepped through hole 13b and screwed to the end of each tie rod 14. Each tightening bolt 15
Are assembled to the respective first support plates 12, and the ends of the respective filters 11 are fitted in the respective first stepped through holes 13a. In this state, the end surface 1 of each filter 11
A predetermined gap is held between 1c and the step end surface 13c of the first stepped through hole 13a.

Thus, each first through hole 12c of the first support plate 12
A tapered portion 12e that expands outward is formed in the opening on the side of the circular recess 12a. This taper portion 12e
Forms an annular space portion by the end outer peripheral surface 11d of the filter 11 and the opening edge portion 13d on the inner end surface side of each first stepped through hole 13a of the second support plate 13, and in this space portion. The O-ring 16 is interposed. O-ring 1
6 is in close contact with the outer peripheral surface 11d of the filter 11, the taper portion 12e of the first support plate 12, and the opening edge portion 13d of the second support plate 13.

In the filter having such a configuration, the liquid to be treated or the gas to be treated (fluid to be treated) is supplied into each filter 11 as shown by the arrow in FIG. 1, and is discharged through the inside of the filter 11. During this time, one composition in the fluid to be processed is separated through the base material 11a and the filtration layer 11b of each filter 11.

By the way, in the said filter, each filter 11 and both support plates 12 and 13 are reliably sealed by each O-ring 16, and each filter 11
End surface 11c and end portion outer peripheral surface 11 of the base material 11a in
Since d is plugged, generation of a bypass flow that flows in the base material 11a is prevented. Therefore, in the filter, it is not necessary to clamp and seal each filter 11 from both ends thereof by the support plates as in the conventional case.
Therefore, even when the filters 11 are thin and long, their strength does not pose a problem during assembly. Further, since a desired gap is allowed between the end surface 11c of each filter 11 and the stepped end surface 13c of the second support plate 13, even if the length of each filter 11 varies more than a predetermined range. Since this variation is sufficiently absorbed by the gap and does not contribute to the seal,
Strict dimensional control of each filter 11 is unnecessary. Furthermore, since the O-ring 16 is used as the seal member, even if steam heating and cooling are repeatedly performed, it is possible to prevent the occurrence of a seal defect such as a conventional cap-shaped seal member due to the progress of creep. It

When each filter has a filter layer on the outer peripheral surface, the same effect can be obtained by plugging only the end surface of the substrate when the average pore diameter of the filter layer is extremely small.

(2) Modified Examples of Sealing Means FIG. 5 to FIG. 7 show three modified examples of the sealing means in the module 10 described above. In the first modification shown in FIG. 5, an annular taper portion 13e that expands outward is formed at the opening portion on the inner end face side of the first stepped through hole 13a of the second support plate 13A. The portion 13e is the first through hole 12 of the first support plate 12A.
The opening edge portion 12f on the outer end surface side in c and the end outer peripheral surface 11d of the filter 11 form a space portion in which the O-ring 16 is interposed. In the second modification shown in FIG. 6, the space in which the O-ring 16 is interposed is the filter 11
End outer peripheral surface 11d, taper portion 12e of the first support plate 12 and taper portion 13e of the second support plate 13A.
It is formed by. In the third modified example shown in FIG. 7, the space portion is the end outer peripheral surface 11d of the filter 11,
The second support plate 13 and the first support plate 12B are formed by an annular recess 12g provided in the opening on the outer end face side of the first through hole 12c.

(3) Seal function test As a filter, it has a filter layer with an average pore size of 0.2 μm on the inner peripheral surface of the substrate, and has an outer diameter of 10 mm, an inner diameter of 7 mm, and a length of 1000 mm.
1. The filter shown in FIG. 1, which employs 19 cylindrical filters, and has the end surface and the outer peripheral surface of the end portion of each filter sealed with glaze, and the conventional filter using each of the above filters. Using the and, the leak test of each seal part was performed. An O-ring 16 made of silicone rubber is used as the seal member in the filter of this embodiment, and the seal member in the conventional filter has the shape shown in FIG.
1 = 3 mm, 12 = 5 mm, 13 = 7 mm, 14 = 10 mm, 1
A cap-shaped sealing member 2 made of silicon rubber and having a size of 5 = 12 mm was used. The leak test is based on the underwater foaming method using air.

(3-1), the length of the filter is 1000mm ±
Although each module was configured with a variation of 0.5 mm, in the module using the cap-shaped sealing member 2, if the tightening margin is increased, an excessive tightening force is applied to each filter to prevent bending. Therefore, the interference is set to 15% of 11 in the seal member 2 (3 mm × 0.15 = 0.45 mm) with the filter length of 1000 mm as a reference. Therefore, in the case of a filter having a filter length of 999.5 mm, the tightening margin is 11 × 0.067.

A leak test by an underwater foaming method was carried out using the filter of the present example accommodating each module and the conventional filter, and the air pressure of the filter of the present example was 6 kg / cm ^2.
However, no leak was found in each seal, but in the conventional filter, a leak was found in part of each seal even when the air pressure was 1 kg / cm ² . It is understood that the filter in which the occurrence of leak is recognized has a filter length of less than 1000 mm, and the seal is insufficient due to insufficient tightening margin.

(3-2) Next, in the conventional filter described above, a filter is selected in which no leak is observed even if the air pressure is increased to 3 kg / cm ² , and the module formed by adopting these filters is housed. Using the conventional filter described above and the filter of this example described above, a leak test was performed by the underwater foaming method when steam heating-cooling was repeated. The steam heating-cooling treatment was repeated by setting the next step as one cycle.

Steam heating (130 ° C, 20min) → air blow (1min) → water washing (20 ° C, 10min) → air blow (1
min) → steam heating (130 ° C., 20 min) In the conventional filter, one filter was broken when the above treatment was performed 50 cycles and two filters were broken after 200 cycles. In addition, in the leak test, when the above treatment was carried out for 150 cycles, the air pressure was 1 kg / cm ² at one filter seal part, and when 370 cycles were carried out, similarly at the two filter seal parts. Occurrence of leak was recognized. On the other hand, in the filter of this example, the filter was not damaged even after 370 cycles of the above treatment, and even if the air pressure was increased to 6 kg / cm ² , the occurrence of leakage at each seal part was recognized. I couldn't do it.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a filter according to an embodiment of the present invention,
2 is a sectional view of the module in the filter, FIG. 3 is a side view of the module, FIG. 4 is an enlarged sectional view of a seal portion in the module, and FIGS. FIG. 8 is an enlarged sectional view showing three modified examples, FIG. 8 is a sectional view of a module in a conventional filter, and FIG. 9 is a sectional view of a seal member in the module. Explanation of symbols 10 ... Module, 11 ... Filter,
11a ... substrate, 11b ... filtration layer, 11c ... end face,
11d ... end outer peripheral surface, 12 ... first support plate, 1
2c ... first through hole, 13 ... second support plate, 13
a: 1st stepped through hole, 14 ... Tie rod, 16 ...
O-ring, 20 ... Casing.

Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B01D 63/00 500 8014-4D 63/06 8014-4D

Claims (1)

[Claims] 1. A plurality of cylindrical filters made of ceramics, each of which is provided with a filtration layer having an average pore size smaller than the average pore size of the same on at least one surface of the inner and outer peripheries of a porous cylindrical substrate. And a pair of first support plates through which both ends of each of these filters are respectively inserted to support the respective filters in parallel, and stepped holes into which both ends of each of the filters are fitted, respectively. A pair of second members assembled to the outside of the support plate and supporting the filters together with the plate.
A support plate is provided, and an annular seal member that seals between the plates and the filters is interposed between the plates on the outer circumference of the end of each filter.
Further, the filter is characterized in that the end surface of the base material and the outer peripheral surface of the end portion of each of the filters are plugged.