JP2012071231A - Filter unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filter unit for chemically filtering metal components in the liquid to be processed, uniformly in the whole processing area of a filter material.SOLUTION: An inlet for the liquid to be processed is formed at the center of a lower end plate (inlet end plate) of a housing. An outlet for the liquid processed is formed in an upper end plate (outlet end plate) of the housing. An end plate of the filter material is supported by a support member. Passages for the liquid to be processed are formed at equal intervals between the lower end plates of the end plate and the housing.

Description

  The present invention relates to a filter unit that removes a metal component in a liquid, and more particularly to a filter unit that is suitable for removing a metal component from a high-concentration, high-viscosity liquid containing metal impurities.

  Conventionally, a metal component in a liquid has been removed using a filter medium in which a fiber base material has an ion exchange ability and a chelate formation ability.

  Such a filter medium is formed, for example, in a hollow cylindrical filter body, accommodated in a cylindrical housing, and used as a filter unit.

FIG. 10 shows an example of such a conventional filter unit.
The filter unit 1 is configured by coaxially arranging a cylindrical filter body 3 in a cylindrical housing 2, and a flow provided at a position outside the filter body 3 of the upper end plate 4 of the housing 2. The liquid to be treated is supplied from the inlet 5 into the housing 2 to pass through the cylindrical filter medium 6 of the filter body 3, and this permeated liquid (treatment liquid) is discharged from the discharge port 7 provided in the center of the housing 2. It is configured.

  When the filter unit 1 having such a structure is used for physical filtration for removing particulate impurities, it preferentially permeates through the filter medium 6 in the housing 2 near the inlet 5 of the liquid to be treated. When the permeation resistance of the liquid to be treated increases due to the accumulation of fine particles on the filter medium, the filtration is performed in a region where the permeation resistance is low and the permeation resistance is low. Used for

  However, when removing metal ions using a filter medium with metal ion adsorption ability or chelate formation ability, even if the metal ions are adsorbed on the filter medium and the metal ion adsorption ability is lost, the permeation of this part is not possible. Since the resistance does not increase compared with physical filtration, the liquid to be treated may pass through the A region where the metal ion adsorption ability is lost even if the region having the metal ion adsorption ability remains. There was a problem that it could not be performed uniformly in the entire processable area.

  This tendency is particularly strong when the liquid to be treated is a high-viscosity liquid such as a high-concentration alkali or sugar liquid, and the permeation of the filtering medium of the liquid to be treated is near the inlet of the liquid to be treated in the housing. Therefore, there is a problem that the filter medium is not used effectively and the service life is short.

  As described above, in the conventional filter unit, when the metal component in the liquid to be treated is removed, the permeation resistance of the liquid to be treated does not increase so much even in the region where metal ions are adsorbed. Is difficult to perform evenly in the entire processable area of the filter medium, and in particular, in the case of a high-viscosity liquid, the flow of the liquid to be processed in the housing tends to be biased, which shortens the service life of the filter medium. There was a problem.

  The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide a filter unit free from the above problems.

  The filter unit of the present invention is an upper plate having a cylindrical shape of a filtering material that adsorbs a metal component in an upright cylindrical housing having a liquid inlet for processing and a processing liquid outlet, and having a drain pipe at one end. A filter body with a fixed end and an end plate fixed at the other end is coaxially arranged, allows the liquid to be processed flowing in from the liquid inlet of the liquid to be processed in the housing to pass through the filter body, In the filter unit configured to discharge from the processing liquid discharge port of the housing through the drain pipe of the plate, the inlet of the liquid to be processed is in the center of the lower end plate (inlet end plate) of the housing, The processing liquid discharge port is formed at the center of the upper end plate (outlet end plate) of the housing, and the end plate of the filter body is supported by a support member, Serial and characterized by being formed at equal intervals of the processing liquid path to the bottom end plates.

The support member for supporting the end plate is preferably disposed so as to be interposed between the end plate and the lower end plate.
Such a support member may be an independent component, or may be a uniform protrusion projecting from the bottom surface of the end plate, such as a plurality of bolts projecting to the same height.
Moreover, it is good also as what arrange | positioned the ring-shaped member which has a to-be-processed liquid path | pass substantially uniformly along the circumferential direction on the side wall on the outer periphery of the to-be-processed liquid inlet of a lower end plate. In this case, the inlet of the liquid to be processed formed on the lower end plate is formed in the step hole, the bottom plate is provided on the ring-shaped member, and a short pipe communicating with the inside of the ring is protruded from the bottom plate. May be inserted into the inflow hole of the lower end plate.

  Moreover, the space between the ring-shaped member having the liquid passage to be treated and the end plate may be filled with a filler such as plastic spherical beads having good corrosion resistance. In this case, the step hole at the inlet of the liquid to be treated A spherical bead is held by sandwiching a tray made of a plastic mesh or punching plate having good corrosion resistance between short pipes protruding from a ring-shaped member having a liquid passage to be treated. The receiving tray may be attached to a step hole at the inlet of the liquid to be processed, or may be attached to the bottom surface of a short pipe projecting from a ring-shaped member having the liquid passage to be processed.

  In the filter unit of the present invention, the inlet of the liquid to be processed is provided at the center of the lower end plate. The number of the inlets of the liquid to be processed is not limited to one, and a plurality (three or more) can be provided. In this case, it is desirable that the inflow ports are arranged at equal intervals on a concentric circle with respect to the center of the lower end plate.

Furthermore, in the filter unit of the present invention, a taper ring that decreases the cross-sectional area of the flow path of the liquid to be processed formed between the housing and the filter body as it goes upward can be disposed along the inner wall of the housing. .
An upper plate with a short tube protruding as a filtrate outlet is fixed to the center of the upper portion of the filter body, as in the conventional case, and this short tube is connected to the central portion of the upper end plate. Connected to the outlet in the housing.

  Various types of filter media can be used depending on the use of the filter medium of the present invention. For example, when the purpose is to remove metal in a high-viscosity liquid, at least the surface of the fiber substrate is used. A functional fiber substrate having a functional group having ion exchange ability or metal chelate-forming ability immobilized thereon, in which a large number of fibers are brought into close contact with each other, can be used.

  Such a filter medium is, for example, wound and fixed in a multi-layered cylindrical shape with an ion exchange resin interposed as necessary on a cylindrical core through which liquid can pass, and the cylindrical wound body An upper plate having a short tube serving as a filtrate outlet is fixed to one end, and an end plate without a hole is fixed to the other end to form a filter body.

  The shape of the filter medium is not limited to the cylindrical shape, and may be a cylindrical body having a cross-sectional shape similar to a cylindrical shape such as a regular decagon, or another cross-sectional shape.

  The filter body is formed by pleating a nonwoven fabric formed of a fiber base material having the above-mentioned metal adsorption ability, wound around the outer periphery of a liquid-permeable cylindrical core in a pleat shape, and ions are interposed between the layers of each nonwoven fabric. It is also possible to hold the replacement resin and fix the above-described upper plate and end plate.

  In the filter unit for high viscosity liquid used in the present invention, the ratio of the diameter of the filter body to the height of the filter body (distance between the bottom surface of the lower plate and the upper surface of the upper plate) is 1: 0.8 to 1: 3. .5, preferably 1: 1 to 1: 2.5, particularly preferably 1: 1.2 to 1: 2.

  The filter unit for high viscosity liquid of the present invention is particularly suitable for filtering a liquid having a viscosity of 10 to 400 mPa · s.

  According to the present invention, the inlet of the liquid to be treated is formed at the center of the lower end plate of the housing of the filter unit, the end plate of the filter body is supported by the support member, and the like between the end plate and the lower end plate. Since the gap gap is formed, the liquid to be processed supplied upward from the inlet of the liquid to be processed collides with the end plate and spreads radially along the end plate while spreading radially around the filter body and the housing. It reaches the cylindrical liquid passage formed on the side, where the flow direction is changed upward and proceeds upward along the surface of the filter medium. In the process, the metal component is removed through the filter medium. .

  Further, by providing a ring-shaped member having a liquid passage to be treated between the lower end plate of the housing and the end plate of the filter body, a uniform and uniform flow can be formed radially toward the outer periphery of the end plate. By filling the ring-shaped member having the liquid passage with the spherical filler, the radial flow toward the outer peripheral direction of the end plate can be made to flow more uniformly.

  As described above, according to the present invention, the liquid to be processed supplied into the housing flows uniformly and radially in the outer peripheral direction of the end plate mainly by the action of the bottom surface of the end plate and the diffusion action of the filler. And the cylindrical processing liquid passage formed on the inner surface of the housing, and is uniformly filtered, so that the filtering medium can permeate the processing liquid evenly, so that the filtering medium can be used efficiently.

  Furthermore, when the taper ring is disposed in the housing, the liquid to be treated permeates equally not only in the circumferential direction of the filter body but also in the longitudinal direction. Exhibits transmission performance and can be used for a long time.

It is sectional drawing of the 1st Embodiment of this invention. It is a perspective view of the filter body of the 1st Embodiment of this invention. It is a top view of the modification of the lower endplate of this invention. FIG. 4 is a perspective view of a lower end plate shown in FIG. 3. It is sectional drawing of the 2nd Embodiment of this invention. It is a perspective view which expands and shows the supporting member of FIG. It is a perspective view which expands and shows the modification of the supporting member of 2nd Embodiment. It is a perspective view which expands and shows the principal part of the supporting member of FIG. 5B. It is sectional drawing of the 3rd Embodiment of this invention. It is an exploded view of 3rd Embodiment. It is a figure explaining the cutting method of the height direction for extract | collecting a test sample from a filter medium. It is a figure explaining the cutting method of the circumferential direction for extract | collecting a test sample from a filter medium. It is sectional drawing of the conventional filter unit.

  Next, an embodiment of the present invention will be described.

[First embodiment]
FIG. 1 is a longitudinal sectional view of a first embodiment of the present invention, and FIG. 2 is a perspective view of a filter body.
In these drawings, reference numeral 11 denotes a filter body, and a functional group having a function of removing metal ions such as an ion exchange group and a chelate forming group is bonded to the surface of a liquid-permeable cylindrical core 12. The fiber base material 13 is formed into a cylindrical shape, and the outermost layer is constituted by a liquid-permeable pressing member 14 and the upper and lower ends thereof are fixed by an upper plate 15 and an end plate 16.

The end plate 16 has a disk shape with the same diameter as the presser member 14, and as shown in FIG. 2, four resin bolts 16a project from the lower surface side so as to have the same height.
The upper plate 15 also has a disk shape having substantially the same diameter as the outer diameter of the pressing member 14, and a short tube 15a having the same diameter as the core 12 serving as the filtrate outlet is provided at the center on the upper surface side. A plurality of O-ring grooves are formed on the outer periphery of the.

The housing 17 includes a straight body portion 18, a lower end plate 19 disposed at the lower portion of the straight body portion 18, an upper end plate 20 disposed at the upper portion, a lower end plate 19 at the upper and lower ends of the straight body portion 18, and an upper portion. It comprises bag caps 21 and 22 and O-rings 23 and 24 for fixing the end plate 20 in a liquid-tight manner.
The straight body portion 18 is a cylindrical body whose inner diameter is larger than the outer diameter of the filter body 11 and whose length is slightly longer than the length of the filter body 11. The upper and lower end portions of the inner surface of the straight body portion 18 are chamfered to serve as accommodating portions for the O-rings 23 and 24. Further, both ends of the outer peripheral surface of the straight body portion 18 are large diameter portions 18a, and screw grooves are formed on the outer periphery of the large diameter portion 18a.

  The lower end plate 19 has a disk shape, and an inlet 25 for the liquid to be processed is formed at the center thereof. An annular convex portion 26 is formed concentrically near the outer periphery of the upper surface of the lower end plate 19. The outer diameter of the annular convex portion 26 is slightly smaller than the inner diameter of the straight body portion 18 so that the lower end of the straight body portion 18 can be fitted. The inner diameter of the annular convex portion 26 is larger than the outer diameter of the filter body 11.

  The upper end plate 20 has a disc shape, and a treatment liquid discharge port 27 is formed at the center thereof, and an air vent hole 28 is formed slightly removed from the treatment liquid discharge port 27. A step hole 27a into which the short tube 15a provided in the upper plate 15 of the filter body 11 can be inserted is formed on the lower surface side of the treatment liquid discharge port 27, and is formed in the same shape as the annular convex portion 26 of the lower end plate 19 near the outer periphery. An annular convex portion 29 of the same size is formed.

  The bag caps 21 and 22 for fixing the straight body portion 18 and the lower end plate 19 and the upper end plate 20 are respectively formed on the inner surface of the cylinder in which a screw portion to be screwed with a screw portion of a large diameter portion of the straight body portion 18 is formed. It is comprised from the latching | locking part latched by the edge part of the shape part 21a, 22a and the lower end plate 19 and the upper end plate 20 which were provided in the end.

  In addition, various well-known materials can be used for the fiber base material which comprises the filter material used for the filter unit of this embodiment according to a use. In addition, each component other than the filter medium can be formed by a material that is lined or coated with a plastic with good corrosion resistance on a wetted part of a plastic with good corrosion resistance or an alloy such as stainless steel.

Next, the operation of this filter unit will be described.
A high-viscosity liquid having a viscosity of, for example, 10 to 400 mPa · s, which is a liquid to be processed, enters the housing 17 from the inlet 25 of the lower end plate 19 of the housing 17. The liquid to be processed that has entered the housing 17 collides with the bottom surface of the end plate 16, and the flow is dispersed in all directions to form a substantially uniform radial flow along the bottom surface of the end plate 16. At this point, the direction of the flow changes upward and rises along the outer periphery of the filter body 11, and passes through the filter body 11 as it rises.

  According to this embodiment, since the inlet of the liquid to be processed is in the center of the end plate and the liquid to be processed flowing into the housing is evenly supplied to the entire circumference of the filter body, the filtration efficiency is high. The service life of the body is also extended.

FIG. 3 is a plan view showing a modification of the lower end plate of the present invention, and FIG. 4 is a perspective view thereof.
The lower end plate 19 has a plurality (three) of inlets for the liquid to be processed at the center.
The three inlets 25a of the liquid to be treated of the lower end plate 19a have the same diameter, and the centers thereof are arranged on a concentric circle C with respect to the center of the lower end plate 19a and are equally spaced. Yes.

Even in the embodiment provided with the lower end plate 19a, the liquid to be treated that has entered the housing 17 from the respective inlets 25a collides with the bottom surface of the end plate, the flow is dispersed in all directions, and the entire circumference of the filter body is evenly distributed. Therefore, the filtration efficiency is high and the service life of the filter body is also extended.
In this embodiment, three resin bolts 16a in the first embodiment are arranged at equal intervals on a concentric circle in accordance with the inflow port, and the position of the inflow port does not overlap with the radial direction from the center. Thus, it is desirable to adjust and arrange the rotational direction position of the filter body.

[Second Embodiment]
FIG. 5 is a cross-sectional view of the second embodiment, FIG. 5A is a perspective view of a support member of this embodiment, and FIG. 5B is a partially enlarged view thereof.
In this embodiment, the support member 20a is composed of a bottomed ring-shaped member filled with a filler, and a short pipe in which the inlet of the lower end plate 19a projects from the center lower surface of the ring-shaped member is a filler. Since the structure is the same as that of the first embodiment except that it is a stepped hole that is fitted through the tray, the same reference numerals are assigned to the same parts as those in FIG.

  As shown in FIG. 5A, the support member 20a of this embodiment includes a bottomed short cylindrical ring-shaped member (X) and spherical beads made of plastic with good corrosion resistance filled in the ring-shaped member (X). Filling material (Y) and a receiving tray (Z) for receiving the filling material (Y).

  The side wall of the tray (X) is formed of a plastic plate having good corrosion resistance, in which a hole 202 serving as a processing liquid passage is cut by a disk cutter or the like, and a short tube 203 is projected downward at the center of the bottom surface. Yes. The side wall holes 202 are formed in a long and narrow rectangle, and are formed in a plurality of rows in the height direction by shifting the positions in the circumferential direction by ½ pitch.

  Note that the ring-shaped member may be configured by a mesh formed on a short cylindrical frame instead of the hole 202 formed by such a cutter.

  An inner surface side of the inlet 25 of the liquid to be treated of the lower end plate 19a is formed in a step hole 25a, and a tray in which a plurality of holes smaller in diameter than the filler (Y) are formed in the step portion of the step hole 25a. (Z) is arranged, and the short tube 203 of the ring-shaped member (X) is fitted thereon. Accordingly, the liquid to be treated passes through the perforated plate (Z) from the inlet 25 and flows into the housing 17, flows so as to sew the gap of the filler (Y), and is dispersed in all directions.

  In this embodiment, since the liquid to be treated supplied from the inlet 25 into the housing 17 flows through the gap between the fillers, the flow is further uniformized and supplied to the entire circumference of the filter body. In addition, the filtration efficiency is high and the service life of the filter body is extended.

  In addition, as the packing (Y), for example, a chemical resistant plastic such as PTFE (polytetrafluoroethylene) having a particle diameter of about 2 to 3 mm is used. It is also possible to use functional resin particles to which a functional group having a bond is bonded.

FIG. 5C is a perspective view of a modified example of the support member 20a.
The support member 20b has a short cylindrical shape in which a plurality of circular holes are formed by replacing the holes 202 on the side wall of the ring-shaped member (X) in FIG. 5B with a plurality of rectangular holes.

  In the side wall 201 of the support member 20b, six circular holes 202 serving as liquid passages to be processed are formed at substantially equal intervals in the circumferential direction, and a short tube 203 serving as a liquid inlet portion to be processed is formed at the lower part. The bottom plate 204 protruding is fixed.

  The number of holes 202a of the liquid passage to be treated in the side wall 201 is not limited to six, and may be more than six as long as it is substantially equal in the circumferential direction. The total cross-sectional area of the plurality of holes 202 is preferably larger than the cross-sectional area of the short tube 203.

  The height of the supporting members 20a and 20b including the bottom plate 204 is equal to the height of the annular convex portion 26 of the lower end plate 19a, and the outer diameter and height of the short tube 203 are stepped holes of the lower end plate 19a. It is set as the dimension which can be fitted to 25a.

Next, the operation of these embodiments will be described based on the second embodiment shown in FIG.
The liquid to be processed that has entered the support member 20a from the inlet 25 flows almost evenly along the bottom surface of the end plate 16 of the filter body 11 through the gap of the bead-like filler (Y), and reaches the edge of the filter body 11. At this point, the flow direction changes upward and rises along the outer periphery of the filter body 11.

  In this way, the liquid to be treated is uniformly supplied to the entire circumference of the filter body, so that the liquid to be treated is evenly permeated from the entire circumference of the filter medium, and metal ions are evenly adsorbed over the entire circumference. The service life is extended.

[Third Embodiment]
FIG. 6 is a sectional view of the third embodiment, and FIG. 7 is an exploded view of this embodiment.
Since this embodiment has the same structure as that of the second embodiment except that the taper ring 30 is housed in the housing 17, the same reference numerals are given to portions common to those in FIG.

  In the tapered ring 30 of this embodiment, the upper end face has the same shape and the same size as the end face of the annular protrusion 29, and the lower end face has an inner diameter larger than the half of the thickness of the annular protrusion 26. The cylindrical shape is shorter than the straight body portion 18 by the annular convex portion 26 of the lower end plate 19 a and the annular convex portion 29 of the upper end plate 20. The outer diameter of the taper ring 30 is the same from the upper end to the lower end, and the inner diameter gradually decreases linearly or convexly from the upper end to the lower end.

  In this embodiment, the flow of the liquid to be processed upward along the outer periphery of the filter body 11 decreases as the liquid permeates through the filter body 11 as it rises. However, the taper ring 30 increases the cross-sectional area of the flow path. Therefore, the pressure drop is small, and the filtration effect is effectively exhibited over the entire surface of the filter medium.

  Therefore, the liquid to be treated can be permeated uniformly not only in the circumferential direction but also in the height direction of the filter medium, further increasing the filtration efficiency and extending the service life of the filter medium.

(Examples and Comparative Examples)
Next, examples and comparative examples will be described.
In the examples, the following liquids to be processed, measuring devices and filter units were used.
[Processed liquid]
High concentration alkali treatment liquid: 48 mass% (18N) sodium hydroxide aqueous solution (Asahi Glass Co., Ltd., trade name: Super alkali)
Cu concentration in the liquid to be treated: 10 μg / kg (ppb)
Ni concentration in the liquid to be treated: 50 μg / kg (ppb)

[Chemicals used]
Nitric acid: 1.0N (6% by mass) nitric acid prepared by adding 70% by mass (15.7N) nitric acid (manufactured by Kanto Chemical Co., Inc .; grade for electronic industry) to ultrapure water.
Hydrochloric acid: 1.0N (4% by mass) hydrochloric acid prepared by adding 35% by mass (11.3N) hydrochloric acid (manufactured by Kanto Chemical Co., Inc .; special grade) to ultrapure water.

[Measurement of metal impurities]
The measurement of metal impurities was performed with an ICP mass spectrometer (ICP-MS) (manufactured by PerkinElmer, trade name: ELANDRC-II).

[Processing equipment] (common)
Example 1 is a filter unit having the structure shown in FIG. 1, Example 2 is a structure shown in FIG. 5, Example 3 is a structure shown in FIG. 6, and Comparative Example 1 is a filter unit having the structure shown in FIG.
Filter body (anion exchanger packed column): Polyethylene substrate
Diameter 140mm, height 257.5mm
Use an anion exchanger whose terminal groups are 90% or more OH groups.
Housing material: Polyvinyl chloride (PVC)
Material of piping: PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer pump: bellows pump (made by Iwaki Co., Ltd., trade name: FS-15HT)
Filling: spherical beads made of PTFE (polytetrafluoroethylene) and having a particle size of 2 to 3 mm

[Specifications of filter body of Example]
(Examples 1 to 3 (Embodiments 1 to 3))
Height between lower plate and upper plate: 257.5mm
Lower plate and upper plate diameter: 140mm
Diameter of support member: 112mm
Support member height: 33 mm
The inner diameter of the short tube of the support member: 34mm
Diameter of 6 holes in support member: 9mm

(Example 3 (Embodiment 3))
Taper ring height: 241.5mm
Taper ring top inner diameter: 158mm
Tapered ring inner diameter: approx. 180mm
Taper angle of taper ring: approx. 2.5 °

[experimental method]
-Cleaning of test module The above-mentioned processing device, PFA piping, PVC column, and pump were all immersed in 1.0N nitric acid (concentration: 6% by mass) for 1 hour or more in advance in order to eliminate metal contamination. Washed with ultrapure water. The nitric acid cleaned parts were assembled into a filter unit.

-Flow of liquid to be treated A 48 mass% aqueous solution of sodium hydroxide with a liquid temperature of 25 ° C is pumped in from the inlet of the liquid to be treated of the filter unit at a rate of 500 ml / min (SV = 10 / hr) with a pump. Was purified.

-Analysis of adsorption | suction metal component This used filter unit was removed, ultrapure water was supplied at 0.75 L / min, and it washed with running water until the effluent became pH 9-10. The filter medium is divided into 12 in the circumferential direction and the height direction of the filter body, and each divided filter body is immersed in 1 L of a regenerant 1.0 N hydrochloric acid for 1 hour, and then the solution is taken out and analyzed by ICP-MS. The distribution of metal impurities was measured.

  As shown in FIG. 8, the test of the filter medium was performed by dividing the filter medium into three equal parts in the height direction (up (14A), middle (14B), and lower (14C)), and as shown in FIG. Divided into 12 equal parts in the circumferential direction (0 to 90 ° (14a), 90 ° to 180 (14b) °, 180 ° to 270 (14c) °, 270 ° to 360 ° (14d)). I went about the material.

The results are shown in Table 1 (Examples 1 to 3) and Table 2 (Comparative Example 1).

  “Metal arrival concentration” in the table is the metal concentration from the beginning of the liquid flow until the metal concentration starts to increase, and “Life” is the flow rate when the metal concentration of the treatment liquid starts to increase. “Total amount of removed metal” is the total amount of metal captured by the filter medium when it reaches “Life”, and is divided by the height division position (upper, middle, lower) and circumferential position (angle). The number (mg) of each specified part is the amount of metal captured by each part of the filter medium at this time.

As is clear from Table 1, in Example 1, the liquid to be treated is supplied upward from the inflow port, collides with the end plate, and spreads radially along the end plate while spreading radially around the filter body and the inner surface of the housing. In this case, the metal component is evenly adsorbed over the entire circumference of the filter body. In Example 2, the uniformity in the circumferential direction is further improved by the effect of uniformizing the flow of the support member, and the amount of metal adsorption is further increased. Further, in Example 3, due to the effect of the tapering, the amount of adsorption is made uniform in each of the circumferential direction and the height direction, and the total amount of metal adsorption is also increased, so that the filter medium is most efficiently used in the embodiment. Can be used.
On the other hand, in the comparative example (conventional product), as is apparent from Table 2, metal adsorption is performed only on the upper part of the filter medium, and there is a large variation in the metal adsorption amount in the circumferential direction, and the total amount of metal removed in life. Is also a low value.

  The filter unit of the present invention can be used not only for removing metal components from high-concentration alkalis, but also as filter units for removing metal components from high-concentration, high-viscosity liquids other than high-concentration alkalis.

  DESCRIPTION OF SYMBOLS 11 ... Filter body, 12 ... Core, 13 ... Fiber base material, 14 ... Holding member, 15 ... Upper plate, 16 ... End plate, 17 ... Housing, 18 ... Straight body part, 19, 19a: Lower end plate, 20: Upper end plate, 20a, 20b ... Support member, 21, 22 ... Bag cap, 23, 24 ... O-ring, 25 ... Inlet of liquid to be treated, 26, 29... Annular projections, 27... Processing liquid discharge port, 28... Air venting hole, 30... Taper ring, X ... Ring-shaped member, Y ... Filler, Z.

Claims (10)

A filter medium that adsorbs metal components is formed into a cylindrical shape in an upright cylindrical housing with a liquid inlet and a liquid outlet, and an upper plate having a drain pipe at one end is fixed and the other end is fixed. A filter body to which a plate is fixed is coaxially arranged, a liquid to be processed flowing from a liquid inlet of the liquid to be processed of the housing is permeated into the filter body, and the process liquid in the filter body is passed through a drain pipe of an upper plate. In the filter unit configured to discharge from the processing liquid discharge port of the housing,
The process liquid inlet is formed at the center of the lower end plate of the housing, and the process liquid discharge port is formed at the center of the upper end plate of the housing, and the end plate of the filter body is formed by a support member. The filter unit is characterized in that a liquid passage to be treated is formed at equal intervals between the end plate and the lower end plate.   The filter unit according to claim 1, wherein the filter body is supported by a support member interposed between the end plate and the lower end plate.   The support member is disposed concentrically on the inner bottom surface of the lower end plate of the housing so as to surround the inlet of the liquid to be processed, and the liquid passage to be processed is provided in the side wall substantially evenly along the circumferential direction. The filter unit according to claim 1, wherein the filter unit is a ring-shaped member.   The filter unit according to any one of claims 1 to 3, wherein a bead-shaped filler is accommodated in the ring-shaped member.   5. The inflow port for the liquid to be treated is formed in the center of the lower end plate of the housing at a plurality of intervals on a circle concentric with the lower end plate. The filter unit according to any one of the above.   The housing is provided with a taper ring that is arranged along the inner wall of the housing to reduce the cross-sectional area of the flow path of the liquid to be processed formed between the housing and the filter body as it goes upward. 6. The filter unit according to claim 1, wherein the filter unit is characterized in that:   The processing liquid discharge port of the filter medium is inserted in a liquid-tight manner into the processing liquid discharge port of the upper end plate via an O-ring. Filter unit.   The filter unit according to any one of claims 1 to 7, wherein the liquid to be treated is a high-viscosity liquid.   The filter unit according to any one of claims 1 to 8, wherein the high-viscosity liquid has a viscosity of 10 to 400 mPa · s.   The filter medium is formed by bundling and fixing a large number of functional fiber base materials in which functional groups having ion exchange ability or metal chelate forming ability are immobilized on at least the surface of the fiber base material, with the fibers closely in contact with each other. The filter unit according to claim 1, wherein:

Images