JP3085791B2 - Filtration method and filtration device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filtration method and a filtration apparatus capable of filtering a stock solution to be filtered by a filtration apparatus to the end.

[0002]

2. Description of the Related Art As a diatomaceous earth filtration apparatus for coating a filtration surface with a filter aid such as diatomaceous earth and filtering a stock solution, an apparatus as shown in FIG. 6 is conventionally known. In this apparatus, a partition 51 is provided horizontally on an upper part of a sealed main body 50 having a cylindrical upper part with a lid and a lower part formed in an inverted conical shape. Stock solution chamber 53
And a filtrate outlet 54 is provided on the ceiling of the filtration chamber 52,
A stock solution inlet 55 is provided below the stock solution chamber 53, and the stock solution inlet 55 is provided.
Is connected to a lower discharge switching valve 57 via a pipe line 56 and to a raw liquid supply switching valve 59 via a raw liquid supply branching path 58 to introduce the raw liquid into the raw liquid chamber 53 and discharge the residual liquid.

[0003] A filtration element 60 is suspended and installed in the stock solution chamber 53. The elements 60 are suspended and supported in the stock solution chamber 53 through the partition wall 51.
A tube body 61 having a closed bottom and a filtrate passage 6 penetrating inside and outside.
, And a wire 63 wound around the outer periphery thereof, and is configured to communicate the filtration chamber 52 and the stock solution chamber 53 via the elements 60.

In the above, first, the filtration element 6
After coating the filter aid with the filter aid in the usual manner, the undiluted solution is introduced into the undiluted solution chamber 53, the undiluted solution is filtered by the filtration elements 60, and the filtrate is filtered through the filtration chamber 52 and the filtrate outlet 54. It is to be collected. An apparatus premised on the above filtering apparatus is disclosed in Japanese Patent Publication No. 3-11804, "A cleaning apparatus for a filtering apparatus using a filter aid".

[0005]

In the prior art described above, in the last stage of the filtration operation, the treatment of the undiluted solution remaining in the main body 50 is performed by, for example, recovering the undiluted solution by using the undiluted solution inlet 55 as an outlet. In addition, it is necessary to perform the treatment with another filtration device, which requires a lot of man-hours and requires a treatment device. Further, in the case of treating a small amount of the residual liquid, the frequency of the treatment is increased, the productivity is poor, and the quality is varied, so that improvement is required. Especially recently,
There is a tendency for small-lot, multi-product production to be regarded as important.
How to treat efficiently is an important issue in the filtration operation.

The present inventors have made the present invention as a result of intensive studies in order to solve the above problems. The present inventors have made the filtration element for filtering the undiluted solution into a double-structured pipe, and If the upper half is configured for normal filtration and the lower half is configured for residual liquid filtration, it is possible to efficiently filter and discharge the remaining raw liquid as well as to filter the raw liquid in the filtration device body. The present invention has been found that it is possible to obtain a filter element for residual liquid in proportion to the size of the apparatus, and has completed the present invention.

Accordingly, an object of the present invention is to efficiently filter the undiluted solution, efficiently filter and discharge the residual liquid in the apparatus main body, and furthermore, the above-described simple configuration and large size of the apparatus. It is an object of the present invention to provide a filtration method and a filtration device which can be performed reliably with a filtration element that is well-known, do not require any post-treatment of the residual liquid, and simplify the filtration process and the filtration operation.

[0008]

Means for solving the above problems are, in claim 1, a filtration method, which comprises a lower stock solution chamber, a middle filtrate chamber, and an upper filtrate chamber separated from each other. A normal filtration element, which is provided in the lower undiluted solution chamber and communicates between the undiluted solution chamber and the intermediate filtration chamber ;
With an inner filtrate tube communicating the chamber with the residual filtrate chamber
Using a filtration device consisting of a residual liquid filtration element, the undiluted solution is introduced from the undiluted solution inlet into the lower undiluted solution chamber in the filtration device,
Filter the undiluted solution through the ordinary filtration element in the undiluted solution chamber,
A step of introducing the filtrate into the filtrate chamber in the middle part and discharging the filtrate from the filtrate outlet; introducing high-pressure air into the filtrate chamber; and introducing high-pressure air into the raw solution chamber through a normal filtration element, and Introducing the residual liquid to the upper residual filtrate chamber through an inner tube inside the residual liquid filtration element;
Discharging the residue remaining in the stock solution chamber.
It is characterized by the following.

According to a second aspect of the present invention, there is provided a filtration device, wherein two partition walls are provided horizontally separated from each other in a vertical direction, an upper residual filtrate chamber having a residual filtrate outlet, a filtrate outlet, and a residual filtrate outlet. A drum-shaped filtration device main body provided with an intermediate filtrate chamber provided with a high-pressure air inlet for liquid treatment, a lower stock chamber provided with a stock solution inlet, and a filtration element vertically provided in the stock chamber;
Consists of a cement, the filter element is inserted and the outer filtrate tube, inside of which consists of an inner filtrate pipe,
The upper part is a normal filtration element and the lower part is a residual liquid filtration element.
The filtration element is usually located
Outer filtrate having normal filtrate passage and normal filtrate communication port
Formed by a tube and a screen covering the outer filtrate tube;
The overflow chamber and the stock chamber are usually connected via a filtration element.
The residual liquid filtration element is
An outer filtrate pipe having a passage and a residual filtrate communication port;
The inner filtrate tube inserted inside the side filtrate tube and the outer filter
It is formed by a screen that covers the fluid tube, and the residual filtrate chamber and the original
The liquid chamber is connected through a residual liquid filtration element,
High-pressure air is introduced into the stock solution chamber through the
The residual liquid in the room is filtered inside the residual liquid filtration element.
The residual liquid is filtered through a tube into the upper residual filtrate chamber.
It is characterized by over-processing. In a third aspect of the present invention, in the second aspect, the normal filtrate communication port has a normal filtrate passage and a filtrate.
The chamber is connected to the residual filtrate passage and the residual filtrate passage.
Make sure that the liquid chambers are connected to each other via the inner filtrate tube.
Features . According to a fourth aspect of the present invention, in the third aspect, the outer filtrate tube and the inner filtrate tube of the filter tube are divided into a lower part and an upper half part of a normal filtration element and a lower part of a residual liquid filtration element. The partitioning section is provided with a partitioning section between the elements.

[0010]

According to the above means, the stock solution in the stock solution chamber is usually filtered by the filtration element and recovered from the filtrate solution chamber, and the remaining solution in the stock solution chamber is filtered by the remaining solution filtration element and recovered from the remaining solution filtration chamber. By performing this by introducing high-pressure air, the residue can also be removed from the element, and the residue can be easily recovered after the recovery of the residual liquid.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the accompanying drawings. 1 is a longitudinal side view of a filtration device according to the present invention, FIG. 2 is an enlarged longitudinal side view of a filtration element, FIG. 3 is an enlarged sectional view taken along line 3-3 of FIG. 2, and FIG. FIG. 5 is a longitudinal sectional view of another embodiment of the filtering element, and FIG. 6 is a longitudinal sectional view showing an example of a conventional filtering device.

In FIG. 1, reference numeral 1 is a longitudinal sectional view of a filtration method according to the present invention and a filtration device for carrying out the filtration method. The filtration device main body 2 of the filtration device 1 comprises a cylindrical body 3, a cap-shaped ceiling 4, and a bottom plate 5, and has a drum shape.
Is attached to the lower end of the body 3 with a bolt or the like, is detachable from the body 3, and is configured to be detachable to open the lower end of the body 3.

A horizontal partition 6 is erected so as to cross the middle upper portion of the body portion 3.
The partition wall 7 is horizontally traversed and erected vertically.
Thus, a stock solution chamber 8 is formed below the lower partition 6, a filtrate chamber 9 is formed between the partitions 6 and 7, and a residual filtrate chamber 10 is formed between the partition 7 and the ceiling 4.

A stock solution inlet 11 for introducing a stock solution into a stock solution chamber 8 is provided at a lower portion of the body portion 3, and a filtrate solution outlet 12 and a residual solution processing liquid medium chamber 9 at an intermediate portion are opposed to each other. A high-pressure air inlet 13 is provided, and a residual filtrate outlet 14 is provided in the upper residual filtrate chamber 10. Each of the entrances 11, 12, 13, 14 is connected to a pipeline, and switching valves 15, 16, 17, 18 are interposed in the pipeline.

In the stock solution chamber 8 described above, as shown in an enlarged manner in FIG.
, And each filter element 19 has the same structure. Each filtration element 19 comprises an outer filtrate tube 20 having a closed bottom 21 and an inner filtrate tube 36 concentrically inserted into the outer filtrate tube 20.
The upper end portion 22 is screwed into the hole portion 23 of the partition wall 6 and fitted, and
The upper flange portion 24 is in contact with the lower surface of the partition 6 via a sealing material or the like.

The upper flange portion 24 of the outer filtrate tube 20
Toward the outer periphery of the intermediate bottom from below, a plurality of concave passages radially as shown in Figure 3 is provided for, usually filtrate passages 25 ...
To form The normal filtrate passages 25 are provided from the upper part to the middle lower part of the outer filtrate pipe 20, and a partition 26 is formed in the middle lower part of the outer filtrate pipe 20.
Formed from the lower end of the passage 25 to the original diameter of the outer filtrate pipe 20 in the outer peripheral direction to form a partition portion 26. The normal filtrate passageway 25 ... top of, to match the passageway 25 ... each of s, usually filtrate communication ports 27 ... ordinary filtrate passage 2
5 ... and likewise provided radially, by conventional filtrate communication ports 27 ... and allowed communicating the annular passage 28 of the normal filtrate passages 25 ... and the outer filtrate tube 20. The annular passage 28 communicates with the filtrate chamber 9 on the partition 6 at the upper end.

A filtration screen 29 formed by, for example, spirally winding a wire is attached to the outer periphery of the ordinary filtrate passage 25 of the outer filtrate tube 20, and the ordinary filtration element 30 is formed as described above.

At the lower part of the outer filtrate pipe 20 below the partition 26 of the outer filtrate pipe 20, a concave portion is formed radially in the same manner as above to form a residual filtrate passage 31. And at the bottom of the residual filtrate passages 31.
A residual filtrate communication port 33 for communicating the annular space 32 in the lower part of the outer filtrate pipe 20 with the residual filtrate passage 31 is provided. similarly
The scan clean 34 attached, constitute a residual liquid filtration element 35.

An inner filtrate tube 36 having a sufficiently smaller diameter is loosely inserted into the outer filtrate tube 20 described above.
The inner filtrate pipe 36 has a hollow pipe shape, and the upper end 37 is sealed and supported in a hole 38 formed in the upper partition 7 via an annular support member 39 having an O-ring or the like mounted on the inner diameter thereof. It is concentrically suspended, loosely and inserted into the outer filtrate tube 20. The support member 39 having a sealing function is provided below the above-mentioned normal filtrate communication port 27 at the upper portion, the partition portion 26.
The upper and lower inner filtrates are further disposed above the residual filtrate communication port 33, and the inner filtrate pipes 36 are concentrically filtered through the outer filtrate.
Tate設the liquid pipe 20, and the support, the lower end 40 of the inner filter liquid pipe 36 is opposed spaced apart from the bottom 21 of the outer filtrate tube 20, ring
Jo space 32 and communicates, on the other hand, the upper end 37 communicates with the residual filtrate chamber 10 above the septal wall 7. The support member 39
The inner filtrate pipe 36 and the inner filtrate pipe 36 may be integrally joined. If these are separate bodies, it is desirable to provide a seal member on the inner periphery of the support member 39 and seal the support member 39.

The above-mentioned filtration method using the filtration device 1 will be described in the order of steps. First, the stock solution to which a filter aid such as diatomaceous earth has been added is introduced into the stock solution chamber 8 by opening the switching valve 15. The switching valve 15 is open, the switching valve 12 is also open, and the switching valves 17 and 18 are closed. The undiluted solution chamber 8 is filled with the undiluted solution, and the filter aid contained in the undiluted solution adheres to the surface of the filtration screen 29 in the lower middle or upper part of the filtration screen 19, and as shown by the imaginary line in FIG. 29
A filtration layer F is formed on the surface of the substrate. The addition of the filter aid into the stock solution chamber 8 is performed only in the initial stage, and is not performed after the formation of the filter layer F as described above. The stock solution is a filtration screen 2
9 and a filtration aid formed by the filter aid, and reaches the normal filtrate passage 25, from the normal filtrate communication port 27 at the top of the passage, through the inner periphery of the outer filtrate pipe 20 and the inner filtrate. The liquid flows into the annular passage 28 in the upper part of the outer periphery of the pipe 36, and is introduced into the filtrate chamber 9 between the lower partition 6 and the upper partition 7 from the opening at the upper end of the outer filtrate pipe 20, and the filtrate outlet 12
The filtrate is recovered from via the pipeline.

At the end of the above-mentioned filtration step, the residual liquid is stored in the stock solution chamber 8, and the residual liquid is discharged as follows. First, the switching valve 15 for introducing the undiluted solution
And the switching valve 16 for collecting the filtrate is closed. On the other hand, the switching valve 18 for collecting the residual filtrate connected to the residual filtrate chamber 10 is opened, and the high-pressure air for treating the residual liquid connected to the filtrate chamber 9 is supplied to the filtrate chamber 9 by opening the switching valve 17. Introduce. The high-pressure air introduced into the filtrate chamber 9 blows out to the normal filtrate passage 25 through the annular passage 28 and the normal filtrate communication port 27, and the filter aid adhering to the filtration screen 29 becomes high-pressure. The air is released from the screen 29 by the jet pressure of the air, and is mixed into the residual liquid. As for the residual liquid, the pressure in the stock solution chamber 8 becomes sufficiently higher than the atmospheric pressure.
The liquid is filtered by the residual liquid filtration screen 34 of the lower residual liquid filtration element 35, reaches the residual filtrate passage 31, and flows into the annular space 32 from the lowermost residual filtrate communication port 33. The residual filtrate in the annular space 32 is passed through the inner filtrate pipe 36.
Flows into the inside through the opening of the lower end portion 40 of the inner filtrate pipe 3
Rises through 6, it flows into the remaining filtrate chamber 10, the remaining
It is collected from the distillate filtrate outlet 14. As described above, the residual liquid in the undiluted liquid chamber 8 is filtered and collected, and finally, the filter aid contained in the residual liquid is deposited on the bottom plate 5 of the main body 2 to process the residual liquid. To end.

In the above steps, the stock solution is filtered, the remaining solution is filtered, and the filter aid is removed from the screen of the ordinary filtration element, and the remaining solution is almost completely recovered. Subsequent, remove the bottom plate 5 of the body 2, and discharge the filter aid which was推積on the bottom plate 5, whereas, undiluted body 2 chamber injection or the like of the high-pressure water in a state of opening the bottom plate 5 8 Wash inside. In addition, it adhered to the outside of the residual liquid filtration screen 34,
Since this part is located at the lower part of the opened main body 2, it can be easily removed from below by a scraping operation or the like, and the cleaning of the undiluted solution chamber together with the injection of high-pressure water, etc. can be easily and reliably performed. And the filter cake can thus be removed.

FIG. 5 shows another embodiment of the filtration element. Also in this embodiment, since the basic structure is the same as that described above, the same portions are denoted by the same reference numerals, and detailed description is omitted. In the present embodiment, the outer filtrate pipe 2 of the filtration element 19 is used.
0, the inner filtrate pipe 36 is divided into upper and lower parts at the section 26.

The upper and lower portions 120, 220 of the outer filtrate tube
On the other hand, in the embodiment, the recess 221 is fitted in the upper end of the lower part, and the protrusion 121 is fitted in the lower end of the upper part in a telescopic manner. The fitting is screwed to ensure the connection between the two. Support members 139, 139 forming seals in which upper and lower end portions 137, 237 of upper and lower portions 136, 236 of the inner filtrate tube are fitted to upper and lower end portions of the outer filtrate tube 120, 220.
, And the upper and lower inner filtrate pipes 136 and 236 are configured to communicate with each other. Upper and lower portions 120 of the outer filtrate tube,
A partition 26 is formed at the butt end of 220. In the drawings, 25 is a normal filtrate passage, 31 is a residual filtrate passage, 2
9 and 34 are filtration screens.

In the above, the filtration element 19 is
Since it is divided at the lower partition part 26, the residual liquid filtration element 135 below the division part is screwed together with the outer filtrate pipe 220 and the inner filtrate pipe 236 with the bottom plate 5 opened. By rotating, it can be pulled out downward, and the lower residual liquid filtration element 135 can be taken out and cleaned.

[0026]

As apparent from the above, according to the present invention,
According to claim 1, in the filtration method, the mutual bottom of the stock solution chamber which is divided into, the intermediate portion filtrate chamber, the residual filtrate chamber of the upper
With, disposed under the stock room, a normal filter element for communicating the filtering chamber of the stock solution chamber and the intermediate portion is formed below the normal element, the residual filtrate and concentrate chamber therein
Liquid filtration element with an inner filtrate tube communicating with the chamber
Using a filtration device consisting of a filter solution, the undiluted solution is introduced from the undiluted solution inlet into the lower undiluted solution chamber in the filtration device, the undiluted solution is filtered through a normal filtration element in the undiluted solution chamber, and the filtrate is filtered into the intermediate filtrate chamber. Introducing high-pressure air into the filtrate chamber, introducing high-pressure air into the stock solution chamber through a filtration element, and removing the residual liquid in the stock solution chamber inside the residual liquid filtration element. And a step of discharging the residue remaining in the undiluted solution chamber through the inner tube through the inner tube. Therefore, of course, the filtration process of the undiluted solution by one filtration device,
The filtration and recovery of the residual liquid can be performed reliably, and there is no need to treat the residual liquid with a separate facility as in the past, and the filtration of the stock solution and the treatment of the residual liquid can be performed efficiently. Excellent as a method and a filtration device. Then, the stock solution remaining in the filtration device can be treated under the same device and under the same conditions, so that productivity can be improved and a filtrate having uniform quality can be obtained.

[0027] In Mataichi single equipment, the filtration process of the stock solution as described above, filtering the residual liquid, is performed to the collection, done with less equipment than conventional in terms of equipment to the processing of the residual liquid, moreover,
Only one man-hour is required, and the filtration process and residual liquid treatment can be performed efficiently with the minimum man-hour, and the process that contributes to labor saving, simplification of work, simplification of filtration process, simplification of filtration operation, etc. is extremely large. Yes,
In addition, since the residual liquid processing can be performed smoothly, quickly, and reliably, there is an effect that switching of the stock solution can be completed in a short time.

[0028] In claim 2, the filtering device, spaced apart horizontally two partition walls in the inner portion up and down, and the residual filtrate chamber of the upper with a residual filtrate outlet, a filtrate outlet, the residual liquid A drum-shaped filtration device main body provided with an intermediate filtrate chamber having a high-pressure air inlet for processing, a lower stock chamber having a stock solution inlet, and a filter element vertically provided in the stock chamber;
Consists of a cement, the filter element is inserted and the outer filtrate tube, inside of which consists of an inner filtrate pipe,
The upper part is a normal filtration element and the lower part is a residual liquid filtration element.
The filtration element is usually located
Outer filtrate having normal filtrate passage and normal filtrate communication port
Formed by a tube and a screen covering the outer filtrate tube;
The overflow chamber and the stock chamber are usually connected via a filtration element.
The residual liquid filtration element is
An outer filtrate pipe having a passage and a residual filtrate communication port;
The inner filtrate tube inserted inside the side filtrate tube and the outer filter
It is formed by a screen that covers the fluid tube , and the residual filtrate chamber and the original
The liquid chamber is connected through a residual liquid filtration element,
High-pressure air is introduced into the stock solution chamber through the
The residual liquid in the room is filtered inside the residual liquid filtration element.
The residual liquid is filtered through a tube into the upper residual filtrate chamber.
Over-processed . Therefore, in the filtration device, the drum-shaped main body is divided into three spaces by two partition walls, each space is connected to the entrance and exit, the filtration element faces the lower undiluted solution chamber, and the filtration element has a double internal / external structure. This is achieved by a configuration in which this is divided into upper and lower parts, a screen and a passage are provided, and the uppermost residual filtrate chamber and the intermediate filtrate chamber are connected through the inner and outer pipes, and high-pressure air is introduced. In addition to simply realizing the above, even when the filtration device body is large and large, it is possible to sufficiently secure an area for treating the residual liquid, and to have excellent performance. Thus, a filtration device capable of treating residual liquid is obtained.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a filtration device according to the present invention.

FIG. 2 is an enlarged vertical sectional side view of a filtration element used in the filtration device.

FIG. 3 is an enlarged sectional view taken along line 3-3 in FIG. 2;

FIG. 4 is an enlarged view of a main part of FIG. 2;

FIG. 5 is a longitudinal sectional view of another embodiment of the filtration element.

FIG. 6 is a longitudinal sectional view showing an example of a conventional filtration device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Filtration apparatus, 2 ... Filtration apparatus main body, 6, 7 ... Partition wall,
 8: undiluted solution chamber, 9: filtrate chamber, 10: residual filtrate
Chamber, 11: undiluted liquid inlet, 12: filtrate outlet, 13: residual
High pressure air inlet for distillate treatment, 14 ...ResidualFiltrate outlet,
 19: Filtration element, 20: Outer filtrate tube, 2
5 ...NormalFiltrate passage, 27 ...NormalFiltrate communication port, 2
9, 34 ... screen, 30 ... normal filtration element,
 31: residual filtrate passage, 35: residual liquid filtration element
G, 36 ... inner filtrate pipe, 33 ... residual filtrate communication
Mouth, 120, 220 ... the outside divided up and downFiltrate
Tube, 136, 236 ... Inside divided up and downFiltratetube.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Koichi Arai 1390-1 Kurami, Samukawa-cho, Koza-gun, Kanagawa Prefecture Inside Arai Iron Works Co., Ltd. (56) References JP-A-61-21709 (JP, A) 20999 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B01D 29/00-29/96

Claims (4)

(57) [Claims] 1. A stock solution chamber having a lower part, a filtrate part in an intermediate part, and a residual filtrate part in an upper part, which are separated from each other , are arranged in the lower part liquid part, and communicate the concentrate part and the filtration part in the intermediate part. And a filter element formed below the normal element.
To allow the stock solution chamber and the residual filtrate chamber to communicate with each other.
Filtration comprising residual liquid filtration element with side filtrate tube
Using the device, the undiluted solution is introduced from the undiluted solution inlet into the undiluted solution chamber in the filtration device, the undiluted solution is filtered through the ordinary filtration element in the undiluted solution chamber, and the filtrate is introduced into the filtrate solution chamber in the middle part. A step of discharging from the liquid outlet, introducing high-pressure air into the filtrate chamber, and introducing high-pressure air into the raw liquid chamber through the normal filtration element, and passing the residual liquid in the raw liquid chamber through the inner pipe inside the residual liquid filtration element. A filtration method comprising: introducing a residue into an upper residual filtrate chamber; and discharging a residue remaining in the undiluted liquid chamber. Wherein the unit horizontally spaced two partition walls vertically to
And a middle filtrate chamber having a filtrate outlet, a filtrate outlet, a high-pressure air inlet for treating the residual liquid, and a lower concentrate chamber having a concentrate inlet. And a filtration element vertically provided in the undiluted solution chamber, and the filtration element comprises an outer filtration liquid pipe and an inner filtration liquid pipe inserted through the inside thereof. And the upper part is usually filtered
Over the element, the bottom forms a residual liquid filtration element, typically the filter element, and usually filtered fluid passage in the upper outer peripheral portion
An outer filtrate pipe having a normal filtrate communication port;
It is formed by a screen covering the liquid tube, and the filtrate chamber and the stock solution chamber are
Usually, it is communicated through a filtration element, and the residual liquid filtration element
And an outer filtrate tube having a residual filtrate communication port, and the outer filter
An inner filtrate tube inserted through the inside of the over-liquid pipe, the outer side filtrate
Formed with a screen covering the tubes, the residual filtrate chamber and the stock solution chamber
Is communicated through a residual liquid filtration element, and high pressure air is usually introduced into the stock solution chamber through the filtration element
And the residual liquid in the undiluted liquid chamber is
Into the upper residual filtrate chamber through the side filtrate tube.
The filtering process effusion, filtration device, characterized in that. 3. The normal filtrate communication port has a normal filtrate passage.
The filtrate chamber is connected to the residual filtrate passage with the residual filtrate passage.
The distillate filtrate chamber is communicated with each other via the inner filtrate tube
3. The filtering device according to claim 2, wherein: 4. The outer filtrate tube and the inner filtrate tube of the filter tube are configured such that a middle filtration element part in the lower to upper half and a residual filtration element in the lower part are vertically divided. 4. The filtration device according to claim 3, wherein the section is provided with a partition between the elements.