JP2012130864A - Hollow fiber membrane module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hollow fiber membrane module capable of suppressing increase of the flowing pressure loss while maintaining the exchange efficiency.SOLUTION: In the hollow fiber membrane module enclosing a hollow fiber membrane bundle in a cylindrical module case and including an inlet port and an outlet port of fluid on the same case surface, the sum of an area of an opening part of the inlet port and an area of an opening part of the outlet port of the fluid in the case is 10% or more and 50% or less of that of the whole of the case, and with respect to the opening center of the inlet port of the fluid, the opening center of the outlet port of the fluid is 180±45° to an axial center of the case, and is arranged in the opposite position across the longitudinal direction center, and the hollow fiber membrane bundle is enclosed to be adhered to the case.

Description

  The present invention relates to a hollow fiber membrane module that performs efficient heat or moisture exchange.

  The hollow fiber membrane module is used for various applications because it has a large membrane area and can be miniaturized. FIG. 7 shows an example of this hollow fiber membrane module. A hollow fiber membrane bundle 6 composed of a plurality of hollow fiber membranes 1 and a module case as shown in FIG. 9, a sealing fixing portion made of a partition resin 4 in which both ends of the hollow fiber membrane bundle 6 are bonded and sealed, and a hollow fiber membrane opening 3 in which both end surfaces of the hollow fiber membrane 1 are open to the partition resin; The module case 9 has a case opening 5 for fluid conduction on the side surface thereof.

  Here, the side surface of the module case is a surface facing the outer portion of the accommodated hollow fiber membrane. The module case is a structure in which a hollow fiber opening end made of a partition wall resin is formed at both ends, and the processing fluid and the fluid to be processed can be separated by a sealing material such as an O-ring.

  Further, in this example, a hollow fiber membrane inner fluid inlet 13, a hollow fiber membrane outer fluid inlet 15, a hollow fiber membrane inner fluid outlet 14, and a hollow fiber membrane outer fluid outlet 16 of the processing fluid and the fluid to be processed are provided. A hollow fiber membrane outer portion port portion 12 and a hollow fiber membrane inner portion header portion 11 housing, and an elastic O-ring 10 that separates and seals each fluid to be treated / treated, etc. Composed. Further, it is also possible to use a module case itself provided with a port portion for lead-in / out fluid and a nozzle for joining.

  In such a hollow fiber membrane module, various devices have been proposed in order to increase the exchange efficiency in humidified membrane modules and heat exchange membrane modules that allow a large amount of gas to flow outside the hollow fiber membrane. .

  For example, in Patent Document 1, there is an example in which circular holes are arranged at both ends of the case of the circular module so that the exchange efficiency is improved by making the flow velocity uniform. Further, in Patent Document 2, an attempt is made to expand the utilization area of the module and increase the exchange efficiency by arranging long holes parallel to the opposite positions so that the fluid is counterflowed at both ends of the substantially rectangular case. Has been made. However, in these module shapes, when a large flow rate of processing or gas to be processed flows outside the hollow fiber, the pressure loss in the module increases sharply, increasing the equipment load for processing and reducing the efficiency of the entire device. There was a fear.

  In addition, there is an example in which a flow path restriction plate is provided in a cylindrical case and circular outlets arranged at opposite positions at both ends are provided to increase the humidity exchange efficiency (Patent Document 3), but the pressure loss is large. It is inevitable to become.

  Furthermore, there is also an example in which a hollow fiber membrane module case that is highly open at opposite positions on both ends is arranged in a housing divided into two parts, but this is for efficiently loading the hollow fiber membrane module into the housing, Since the hollow fiber bundle is not intimately enclosed in the case, most of the flow becomes cross flow, and the flow of the hollow fiber membrane module is made a cross + counter as in the present invention, so that the exchange efficiency cannot be improved. (Patent Document 4).

JP 2005-224719 A JP 2007-283292 A JP 2007-323982 A JP 2009-16230 A

  As described above, in order to increase the exchange efficiency, when a large flow rate of processing or gas to be processed is flowed outside the hollow fiber, the pressure loss in the module increases sharply, increasing the equipment load for processing and the efficiency of the entire device. There was a risk of lowering. Therefore, a hollow fiber membrane module design that reduces the increase in flow pressure loss while maintaining the exchange efficiency has been demanded.

  As a means for solving the above-mentioned problems, the present invention is characterized by appropriately securing the area of the opening in the module case and setting the position of the opening center of the fluid outlet.

  Reduce the pressure loss when the flow rate is increased by securing the area of the opening of the module, and also position the center of the opening of the fluid outlet at the position opposite to the axial center and the longitudinal center. Thus, a hollow fiber membrane module capable of improving heat or moisture exchange efficiency is provided.

The present invention is achieved by the following configurations (1) to (4).
(1) A hollow fiber membrane module having a fluid inlet and outlet in the same case, wherein the area of the opening in the case is 10% or more and 50% or less of the entire case, and the introduction of fluid The hollow fiber membrane bundle is located at a position where the opening center of the fluid outlet port is 180 ± 45 ° with respect to the axial center of the case with respect to the opening center of the port and is opposed to the center in the length direction. Is a hollow fiber membrane module characterized by being enclosed in close contact with the case.
(2) The hollow fiber membrane module according to claim 1, wherein in the length direction of the case, at least three portions including both ends of the case have a band portion on the outer periphery having a width of 5 mm or more and not opened. .
(3) The hollow fiber membrane module according to any one of claims 1 to 2, wherein gas is conducted to the outside of the hollow fiber membrane.
(4) The hollow fiber membrane module according to any one of claims 1 to 3, wherein the hollow fiber membrane is a humidified membrane or a heat exchange membrane.

  The hollow fiber membrane module of the present invention reduces the pressure loss when the flow rate is increased by ensuring the opening area of the fluid outlet in the module case. And the hollow fiber membrane module which can improve the exchange efficiency of a water | moisture content or heat | fever by arrange | positioning in the position facing with respect to the center of a length direction is provided.

It is sectional drawing which shows an example which incorporated the hollow fiber membrane module which concerns on this invention in the housing | casing. FIG. 2 is a development configuration diagram of a circular opening disposed in a circular module case housed in the hollow fiber membrane module of FIG. 1. It is a block diagram of the circular opening part arrange | positioned at the rectangular module case accommodated in the hollow fiber membrane module of FIG. It is an expanded block diagram of the circular case which has a rectangular opening part. It is an expanded block diagram of the rectangular case which has a circular opening part. It is a perspective view which shows an example of the conventional hollow fiber membrane module case. It is sectional drawing which shows an example which incorporated the conventional type hollow fiber membrane module in the housing | casing. It is a figure showing the opening center of the opening part arrange | positioned on the module case side surface.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view showing an example of a hollow fiber membrane module according to the present invention as described above.

  A bundle of hollow fiber membranes 1 is inserted into a module case 9 having an opening as shown in FIGS. 2 and 3, both ends of the module case are sealed with an adhesive 4 by a known method, and both end surfaces are cut. Thus, the hollow fiber membrane opening 3 is formed. The module case 9 is fixed by a support 17 together with a header portion 11 and a port portion 12 provided with fluid outlet ports on the inside / outside of the hollow fiber membrane, and an O-ring 10 for sealing to constitute a module.

  Here, the module case appropriately secures the area of the opening and sets the position of the opening center of the fluid outlet. By securing the area of the module's opening, the rise in pressure loss when the flow rate is increased is reduced, and the center of the opening of the fluid outlet is located at a position opposite the axial center and the longitudinal center. Improve exchange efficiency.

  Increasing the opening area as much as possible can suppress the flow resistance and reduce the increase in pressure loss.However, depending on the arrangement of the opening, it may cause a short path of the fluid, forming a dead space and reducing the exchange efficiency. . Therefore, the area of the opening in the case is 10% or more and 50% or less of the entire case. In this case, a zone that shuts off the hollow fiber membrane outer fluid inlet and the hollow fiber membrane outer outlet is formed at the center, but it is also possible to change the opening area on the fluid inlet side and outlet side. It is determined as appropriate in order to make an exchange. Even in this case, the area of the opening is preferably set to 10% or more and 50% or less for the fluid inlet side, the fluid outlet side, and the entire case.

  The center of the fluid outlet is 180 ± 45 ° with respect to the center of the cylindrical case relative to the center of the fluid inlet, and is located at a position opposite to the center in the length direction. To do. This is necessary to effectively utilize the entire filled hollow fiber membrane, and is an important requirement for avoiding a short path of fluid.

  Furthermore, the opening center of the fluid outlet is disposed at a position opposite to the center in the length direction with respect to the opening center of the fluid inlet. As a replacement method using the hollow fiber membrane module, there are a method of flowing the processing fluid and the fluid to be processed to the counter and a method of flowing to the cloth. In the present technology, these are used in combination. In other words, an ideal replacement module can be obtained by setting an arrangement that can form both a counter flow with high replacement efficiency and a cross flow that can reduce an increase in pressure loss. Therefore, the technology of the present invention can exert its effect in a humidifying membrane module or a heat exchange membrane module that processes a large volume of gas.

  In the present invention, in order to form such a flow, the hollow fiber bundle to be included is disposed in close contact with the case. That is, the bundle inserted at the time of creating the module is inscribed in the case, and the inscribed portion is arranged so that the fluid conducting outside the hollow fiber membrane does not short-pass the outer peripheral portion. However, even if a slight short pass occurs during actual use, it is forgiven as long as the counter flow that is the object of the present invention can be formed. The “contact” state is determined by observing the arrangement state of the yarn bundle from the opening of the module. In order to place the hollow fiber bundle in close contact with the case, it is also an effective means to fix the yarn bundle with a knitted material as shown in FIG.

  In addition, the “band part” means a part having a certain width constituted by a substantially straight line on the case, and at this position, the hollow fiber outer side and the hollow fiber outer side, or the hollow fiber outer side entrance and the hollow This is a portion where an O-ring or the like that can shut off the exit outside the yarn can be arranged.

Production of Hollow Fiber Membrane A membrane-forming stock solution comprising 18 parts of a polysulfone resin (P3500 manufactured by Solvay), 9 parts of polyvinylpyrrolidone (K30 manufactured by ISP), 72 parts of dimethylacetamide and 1 part of water was dissolved at 90 ° C, and then 50 ° C. In a double tube cap having an outer diameter of 1.0 mm, a slit width of 0.15 mm, and a core liquid injection hole diameter of 0.3 mm, and discharged simultaneously with a core liquid consisting of 40 parts of dimethylacetamide and 60 parts of water. It passed through a dry part 350 mm, and was immersed in a coagulation bath 40 ° C. of 90 parts of water and 10 parts of dimethylacetamide to be solidified. Next, the coagulated hollow fiber membrane was washed in a water washing bath at 80 ° C., 170 dtex polyester processed yarn was wound around two hollow fiber membranes, and after covering, it was wound around a winding cassette. The wound hollow fiber membrane was dried with a dry heat dryer at 50 ° C. for 24 hours to obtain a hollow fiber membrane bundle.

Center of the opening on the case As shown in FIG. 7, when holes having the opening areas of S1, S2, S3,... Are arranged at the coordinates, x1y1, x2y2, x3y3,. The opening center xGyG is expressed by the following equation.
xG = (s1 × x1 + s2 × x2 + s3 × x3 + ……) / (s1 + s2 + s3 + ……)
yG = (s1 × y1 + s2 × y2 + s3 × y3 + ……) / (s1 + s2 + s3 + ……)
Opening ratio of the case The outer surface portion of the cylindrical or rectangular case is developed on a plane, and the ratio of the total area of the opening portions arranged thereon to the developed case area is defined as the opening ratio.

The axial center of the case and the center in the longitudinal direction of the case In the hollow fiber bundle inserted in the case, the center of the ring-cut surface of the hollow fiber bundle is the axial center, and the line perpendicular to it is the length direction.

Leakage Air Volume Test The hollow fiber membrane inner fluid outlet 14 and the hollow fiber membrane outer fluid inlet 15 of the apparatus comprising the module and casing of FIG. 1 are closed, and 50 kPa air pressure is applied from the hollow fiber membrane inner fluid inlet 13. At this time, the amount of air coming out of the hollow fiber membrane outer fluid outlet 16 is measured and used as a leakage air amount.

Aeration pressure loss test The hollow fiber membrane outer fluid inlet 15 and the hollow fiber membrane outer fluid outlet 16 of the apparatus including the module and the housing of FIG. It discharges from the inner membrane fluid outlet 14. The differential pressure between the hollow fiber membrane inner fluid inlet 13 and the hollow fiber membrane inner fluid outlet 14 at that time is defined as the hollow fiber inner ventilation pressure loss. Similarly, the hollow fiber membrane inner fluid inlet 13 and the hollow fiber membrane inner fluid outlet 14 are closed, vented from the hollow fiber outer fluid inlet 15 and discharged from the hollow fiber membrane outlet 16. The differential pressure between the hollow fiber membrane outer fluid inlet 15 and the hollow fiber membrane outer fluid outlet 16 at that time is defined as the hollow fiber membrane outer airflow pressure loss.

Humidification performance test The apparatus comprising the module and the case of FIG. 1 is immersed in a thermostatic bath at 80 ° C., and air having a dew point (Dpii) of −10 ° C. and a temperature of 20 ° C. from the hollow fiber membrane inner fluid inlet 13 of the module. Is vented at a predetermined flow rate. This air is humidified to a predetermined dew point (Dpoi) with a humidifier, and vented from the hollow fiber membrane outer fluid inlet 15. At this time, the dew point (Dpio) of the exhaust air from the hollow fiber membrane inner outlet 14 and the dew point (Dpoo) of the exhaust air from the hollow fiber membrane outer outlet 16 were measured, and the hollow fiber inner outlet moisture relative to the hollow fiber outer moisture amount was measured. Calculate humidification efficiency (Eh) and overall mass transfer coefficient (Ko), defined by quantity.
Eh = Wio / Woi × 100%
Ko = M / A / (ΔW) m
(ΔW) m = (ΔW2-ΔW1) / (Ln (ΔW2 / ΔW1)
Here, Wio is the hollow fiber inner outlet air moisture content calculated from Dpio, Woi is the hollow fiber outer inlet air moisture content calculated from Dpoi, Ko is the overall mass transfer coefficient (m / h), and M is the mass transfer amount. (G / h), A is the inner diameter equivalent effective membrane area (m ² ), (ΔW) m is the logarithm average moisture difference (g / m ³ ), and ΔW1 and ΔW2 are hollow fibers calculated from the dew points of the respective air The water content difference at the fluid inlet 13 and the fluid outlet 14 inside the membrane is shown.

  At this time, when evaluating the humidification performance between the hollow fiber membrane inner fluid introduction port 13 and the hollow fiber membrane inner fluid outlet port 14, the hollow fiber membrane inner air flow pressure loss, and the hollow fiber membrane outer fluid introduction port 15 and the hollow fiber membrane outer side. The air flow pressure loss outside the hollow fiber membrane is measured when evaluating the humidification performance with the fluid outlet port 16.

Heat Exchange Test Warm water at about 50 ° C. is passed through the hollow fiber membrane inner fluid inlet 13 of the apparatus comprising the module and casing of FIG. 1 at 1 L / min. At the same time, air at a temperature of about 25 ° C. is passed through the hollow fiber membrane outer fluid inlet at 1000 NL / min. At this time, the temperature of the exhaust air from the hollow fiber membrane inner fluid outlet 14 is measured, and at the same time, the temperature of the exhaust air from the hollow fiber membrane outer fluid outlet is measured, and according to the following formula, the overall heat transfer coefficient (kcaL / h / m ² / ° C.).
U = Q / A / (Δt) m
(Δt) m = (Δt2−Δt1) / (Ln (Δt2 / Δt1)
Where U is the overall heat transfer coefficient (kcal / h / m ² / ° C.), Q is the amount of heat transferred (kcal), A is the effective membrane area in terms of inner diameter (m ² ), and (Δt) m is the logarithm average temperature difference ( ° C.), Δt1 and Δt2 indicate temperature differences at the fluid inlet 13 and the fluid outlet 14 inside the hollow fiber membrane, respectively.

  At the same time, the air flow pressure loss outside the hollow fiber membrane between the hollow fiber membrane outer fluid inlet 15 and the hollow fiber membrane outer fluid outlet 16 is measured.

  Examples Hereinafter, the method for producing a hollow fiber membrane membrane module of the present invention will be described in more detail with reference to the drawings, but the present invention is not limited to these.

[Example 1]
In a cylindrical case as shown in FIG. 2, a cylindrical net 2 made of a polyester net having an opening ratio of 46% and a mesh pitch of 840 μm is disposed, and an outer diameter of 790 μm and an inner diameter of 610 μm are arranged therein. The hollow fiber membrane bundle 6 composed of 2910 polysulfone hollow fiber membranes was inserted using a slippery film. This case has an outer diameter of 70 mm, a thickness of 3 mm, and a length of 296 mm. 16 φ30 mm large-diameter holes and 6 φ20 mm small-diameter holes are arranged at the positions shown in FIG. There is a non-opening band part with a width of 20 mm in the vicinity of both ends and in the center of the case. The opening center of one multi-opening part is 57 mm from the end (91 mm from the center in the length direction) and the axial center circumferential position is 120 ° The other opening center is arranged at a position of 239 mm from the end (-91 mm from the length center) and 300 ° in the axial center circumferential direction. The total aperture ratio is 20%. After sealing both ends of the hollow fiber membrane bundle, centrifugal potting was performed to cut both ends and open the hollow fiber membrane. The condition of the yarn bundle was confirmed from the opening of the case, and it was confirmed that the yarn bundle and the inner wall of the case were in close contact. The case 9 is supported by a header part 11 having a hollow fiber membrane inner fluid outlet inlet at both ends and a port part 12 provided with a hollow fiber membrane outer fluid outlet inlet so that each is sealed with an O-ring 10. 17 was used to create a circular module as shown in FIG. The effective membrane area in terms of the inner diameter of the hollow fiber membrane was 1.5 m ² . The leakage air amount of this module was 1 L / min or less, and the hollow fiber membrane was not damaged. As a result of conducting a heat exchange test using this module, the overall heat transfer coefficient showed a good heat exchange performance of 204 kcaL / h / m ² / ° C. when 1000 NLM was ventilated. At this time, the increase in air pressure loss outside the hollow fiber membrane was 5 kPa.

[Comparative Example 1]
A module having an aperture ratio of 9% as shown in FIG. 2 / Table 1 / Table 2 having a hollow fiber membrane bundle configuration similar to that of Example 1 was prepared. In the heat exchange test of this module, the overall heat transfer coefficient was slightly improved to 240 kcaL / h / m ² / ° C. when 1000 NLM was ventilated, but the increase in air pressure loss outside the hollow fiber membrane was as high as 12 kPa.

[Example 2]
Table 2 / Table 1 / Table 2 with an outer diameter of 80 mm, a length of 296 mm, and an effective membrane area of 2.0 m ² comprising a hollow fiber membrane bundle composed of 3850 polysulfone hollow fiber membranes having an outer diameter of 840 μm and an inner diameter of 620 μm A module having a hollow fiber membrane outer fluid inlet side and outlet side opening ratio of 15% was prepared. A non-opening belt-like portion having a width of 12 mm is provided in the vicinity of both ends and in the center of the case. The opening center of one multi-opening portion is 52 mm from the end in the length direction (96 mm from the center in the length direction), and the axial center circumferential position 120 The other opening center is arranged at a position of 244 mm from the end (-96 mm from the center in the length direction) and a position in the axial center circumferential direction of 300 °. The effective membrane area in terms of the inner diameter of the hollow fiber membrane was 2.0 m ² . The leakage air amount of this module was 1 L / min or less, and the hollow fiber membrane was not damaged. Using this module, 1000 NLM was ventilated from the hollow fiber membrane inner fluid inlet, and this air was humidified to a dew point of 63 ° C., and as a result of a humidification performance test, the dew point of the hollow fiber membrane inner fluid outlet was 51 The humidification efficiency was 60%, and the overall mass transfer coefficient was 44 m / h. At this time, the increase in the outside air pressure loss of the hollow fiber membrane was 9.5 kPa, and the increase of the air pressure loss inside the hollow fiber membrane was 5.3 kPa, which showed good performance as a humidifier.

[Example 3]
As shown in FIG. 3 / Table 3 / Table 4 with an outer diameter of 150 mm × 50 mm and an effective membrane area of 2.9 m ² composed of a hollow fiber membrane bundle structure composed of 2670 polysulfone hollow fiber membranes having an outer diameter of 850 μm and an inner diameter of 680 μm. A rectangular module having a hollow fiber membrane outer fluid inlet side and outlet side opening ratio of 18% was prepared. There is a 12mm wide non-opening strip in the vicinity of both ends and in the center of the case. The opening center of one multi-opening is 82mm from the end in the length direction (66mm from the center in the length direction) and 75mm in the center in the width direction. The center of the other opening is 214 mm from the end (-66 mm from the center in the length direction) and 75 mm in the center in the width direction position (180 ° in the circumferential direction about the axis with respect to the other opening center). The effective membrane area in terms of the inner diameter of the hollow fiber membrane was 2.9 m ² . The leakage air amount of this module was 1 L / min or less, and the hollow fiber membrane was not damaged. Using this module, 1330NLM was ventilated from the hollow fiber membrane inner fluid inlet, this air was humidified to a dew point of 68 ° C., and a humidification performance test was conducted. As a result, the dew point of the hollow fiber membrane inner fluid outlet was 61 The humidification efficiency was 75%, and the overall mass transfer coefficient was 79 m / h. At this time, the increase in the air pressure loss outside the hollow fiber membrane was 7.7 kPa, and the increase in the air pressure loss inside the hollow fiber membrane was 4.8 kPa, indicating good performance as a humidifier.

1. Hollow fiber membrane 2. Net-like material 3. Hollow fiber membrane opening 4. Adhesive Case opening 6. 8. Hollow fiber membrane bundle Module case 10. O-ring 11. Header part 12. Port part 13. Hollow fiber membrane inner fluid inlet 14. 15. Hollow fiber membrane inner fluid outlet 15. Hollow fiber membrane outer fluid inlet 16. 16. Hollow fiber membrane outer fluid outlet 17. Hollow fiber membrane outer fluid inlet pressure measurement point 18. 18. Hollow fiber membrane outer fluid outlet pressure measurement point Support tool 21. Open cylindrical case 22. FIG. Circular opening 24. Rectangular opening 25. Open rectangular case

Claims (3)

A hollow fiber membrane module containing a bundle of hollow fiber membranes in a cylindrical module case, and having a fluid inlet and outlet on the same case surface, the area of the opening portion of the fluid inlet in the case and The sum of the areas of the fluid outlet openings is 10% or more and 50% or less of the total area of the case, and the center of the fluid outlet is the center of the case axis relative to the center of the fluid inlet. A hollow fiber membrane module, wherein the hollow fiber membrane module is disposed at a position that is 180 ± 45 ° relative to the center in the longitudinal direction and the hollow fiber membrane bundle is enclosed in close contact with the case. 2. The hollow fiber membrane module according to claim 1, wherein in the length direction of the module case, at least three portions including both ends of the case have a band portion on the outer periphery with a width of 5 mm or more that is not opened. The hollow fiber membrane module according to claim 1, wherein the hollow fiber membrane is a humidified membrane or a heat exchange membrane.

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