JPH10156150A - Hollow fiber membrane module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inner pressure type hollow-fiber membrane module which is easily subjected to complete disinfection by steam and in which resin partitions are formed by centrifugal mold injection work of easy and simple equipment in vertical inner pressure type hollow yarn membrane modules in which resin partitions at both ends in a cylindrical case are formed by a centrifugal mold injection method. SOLUTION: The inner surface in contact with permeated liquid of a lower side resin partition 41 is made as a concave grooved surface 'a'. The center line c-c of the grooved bottom surface is directed in the direction of the center line e-e of a lower side path port 21, and the bottom surface central part 'b' of the concave grooved surface is made as a formed surface the inner surface of the lower side path port 21 of which has no step or is raised. The lower side path port 21 is made at a takeoff port for residual liquid and the upper side path port 22 is as made a permeated liquid takeoff port.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD OF THE INVENTION

The present invention relates to an internal pressure type hollow fiber membrane module.

[0002]

2. Description of the Related Art As a hollow fiber membrane module, a hollow fiber membrane bundle is accommodated in a cylindrical case, and resin partition walls are formed at both ends of the cylindrical case. The side with a passage opening on the side is commonly used.In the case of the internal pressure type, it is usually installed vertically, the hollow fiber membrane end on the outer end surface of the lower resin partition is used as the undiluted liquid inlet, and the upper resin partition is The end of the hollow fiber membrane on the outer end surface is used as a stock solution outlet, the lower passage opening is closed, and the upper passage opening is used as a permeate outlet. When the operation of the internal pressure type hollow fiber membrane module is started or timely stopped, sterilization is performed by passing heated steam from the lower passage opening into the upper passage opening.

[0003]

SUMMARY OF THE INVENTION The above hollow fiber membrane module
It is known to form a resin partition of a metal by a centrifugal casting method. However, in the conventional resin partition formed by the centrifugal casting method, according to the study results of the present inventors, it is difficult to completely sterilize the inner surface of the lower resin partition as a condensed water pool during the steam sterilization described above. It is.

SUMMARY OF THE INVENTION An object of the present invention is to provide a vertically placed internal pressure type hollow fiber membrane module in which resin partition walls at both ends of a cylindrical case are formed by centrifugal casting. It is an object of the present invention to provide a hollow fiber membrane module.

[0005]

In the hollow fiber membrane module according to the present invention, a hollow fiber membrane bundle is accommodated in a cylindrical case, and a resin partition is centrifuged at both ends in the cylindrical case. In a vertically mounted internal pressure type hollow fiber membrane module in which a casting is provided and a passage opening is provided on the side surface of both ends of the cylindrical case, the inner surface of the lower resin partition wall which is in contact with the permeated liquid is a concave curved groove surface. The center line of the bottom of the groove faces the center line of the lower passage opening, and the center of the bottom surface of the concave curved groove surface is a molding surface with no step or raised inside the lower passage opening. The passage is an outlet for the residual liquid, and the upper passage is an outlet for the permeated liquid.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1A shows an internal pressure type hollow fiber membrane module according to the present invention, which is installed vertically. FIG. 1B is a cross-sectional view of FIG.
FIG. In FIG. 1, reference numeral 1 denotes a cylindrical case, which is made of a heat-resistant plastic such as polysulfone or metal.
For example, stainless steel or the like is used. 11 is an upper end piece of a cylindrical case having a passage opening 21 on the side surface, and 12 is a lower end piece of a cylindrical case having a passage opening 22 on the side surface.
Integrated with an adhesive or the like. Numeral 3 is a bundle of hollow fiber membranes accommodated in the cylindrical case 1 and uses a microfiltration membrane or an ultrafiltration membrane. Reference numerals 41 and 42 denote resin partition walls formed by centrifugal casting on both ends of the cylindrical case.
−c is oriented in the direction of the center line ee of the lower passage opening 21, and the bottom surface center portion b of the concave curved groove surface a is continuous with the inner surface of the lower passage opening 21 without any step. A curable resin such as an epoxy resin or a polyester resin is used as the resin for the partition walls. Reference numeral 51 denotes a raw water inlet, and a hollow fiber membrane is opened at an outer end surface of the lower resin partition wall 41. 52
Is a raw water outlet, and a hollow fiber membrane is opened at the outer end surface of the upper resin partition wall. The raw water inlet 51 is connected to a raw water supply pipe via a joint, and the raw water outlet 52 is connected to a raw water discharge pipe via a joint, but these are not shown.

To treat raw water with the hollow fiber membrane module according to the present invention, raw water is injected into the hollow fiber membrane from the raw water inlet 51, and the solvent of the raw water passing through the hollow fiber membrane is permeated through the membrane. ,
The raw water in which the solute is concentrated by this permeation, that is, the concentrated water, is discharged from the raw water outlet 52, and the permeate is taken out from the upper passage opening 22.

Before the operation of the hollow fiber membrane module and when the operation is interrupted at an appropriate time, the cylindrical case 1 is inserted through the lower passage opening 21.
Sterilization is performed by flowing steam toward the upper passage opening 22 through the inside. In this case, the steam is the outer surface of the hollow fiber membrane,
The condensed water is condensed by contact with the inner surface of the cylindrical case and the inner surface of the resin partition, and the condensed water drips on the inner surface a of the lower resin partition and flows out from the lower passage opening 21. Since the flow path to the inner surface of the passage opening is a surface having no reverse slope, condensed water can be smoothly discharged without stagnation and steam heating can be efficiently performed, and from the comparison between Examples and Comparative Examples described below. As is clear, complete sterilization can be easily performed.

In the above, in the centrifugal casting of the inner surface of the lower resin partition wall into the concave curved groove surface, the rotation axis O of the centrifugal casting coincides with the center of gravity g of the module A as shown in FIG. At the same time, the module is set in a centrifugal casting machine so as to be directed toward the center line of the lower passage opening, and the injected resin liquid is cured along the rotation path of radius R. In the above, the central part of the bottom surface of the concave curved groove surface may be made more convex than the inner surface of the lower passage opening.

FIG. 2 shows resin partition walls at both ends of the hollow fiber membrane module.
When the centrifugal casting is performed as shown in FIG. 7, since the inner surfaces of the upper and lower resin partition walls 41 and 42 are vertically symmetrical under the same amount of resin, the lower passage opening 21 and the upper passage opening 22 are vertically symmetrical. By doing so, the permeated water flow surface from the inner surface of the upper resin partition to the inner surface of the upper passage opening has no reverse slope with respect to the flow, or the upper passage opening 22 of FIG. The positions can be different from each other by 180 ° in the same horizontal plane.

[0011]

【Example】

[Embodiment] The construction shown in FIG. 1 is such that a polysulfone cylinder having an inner diameter of 85 mm and a length of 1077 mm is used for a cylindrical case, and an inner diameter of 0.55 mm and an outer diameter of 1.1 m are used for a hollow fiber membrane.
m, an ultrafiltration membrane having a molecular weight cut off of 6,000 was used, and an epoxy resin was used as a casting resin. The effective membrane area of the module is 6.3 m ² and the initial pure water permeate is 2.3 m ³ / h.
1 kgf / cm ² · 25 ° C. In FIG. 1, the depth d of the concave curved surface of the lower resin partition wall was 3 mm. [Comparative Example] The axial direction of the rotation axis of the centrifugal casting was different from the centrifugal casting in the embodiment so that the center line of the bottom of the concave curved groove and the center line direction of the lower passage opening form an angle of 90 °. Was substantially the same as the example except that the angle was shifted by 90 °.

In the modules of this embodiment and the comparative example, steam having a heating temperature of 128 ° C. was sent vertically from the lower passage opening to the upper passage opening through the cylindrical case for about 20 minutes. When sterilization was performed, the inner surface temperature of the lower resin partition wall was 122 ± 2 ° C. in the comparative example, whereas it was 126 ± 2 ° C. in the example. The cause is presumed to be that the condensed water easily stays on the inner surface of the lower resin partition wall in the comparative example. After this sterilization treatment, pure water was supplied by the modules of Examples and Comparative Examples to an inlet pressure of 1.0 kg / cm ² , a recovery rate of 90%,
When the membrane separation treatment was performed at a temperature of 25 ° C., the viable cell count of the permeated water was 0 even after 150 hours from the start of the membrane separation treatment.
(Cfu / ml), but reached 120 (cfu / ml) in the comparative example. Therefore, it is clear that the example product was completely sterilized.

[0013]

According to the present invention, a condensed water reservoir can be favorably eliminated in a vertically placed internal pressure type hollow fiber membrane module in which resin partition walls at both ends inside a cylindrical case are formed by centrifugal casting. An internal pressure type hollow fiber membrane module can be provided in which the lower resin partition wall can be cast and complete sterilization by steam can be easily performed.

[Brief description of the drawings]

FIG. 1 is a view showing a hollow fiber membrane module according to the present invention.

FIG. 2 is a drawing used for explaining centrifugal casting of a resin partition wall of the hollow fiber membrane module according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylindrical case 21 Lower passage opening 22 Upper passage opening 3 Hollow fiber membrane bundle 41 Lower resin partition wall 42 Upper resin partition wall Line ee Center line of lower passage opening

Claims (2)

[Claims] A hollow fiber membrane bundle is accommodated in a cylindrical case, and resin partition walls are centrifugally cast at both ends of the cylindrical case. In the vertical internal pressure type hollow fiber membrane module provided with, the inner surface of the lower resin partition wall which is in contact with the permeate is a concave curved groove surface, and the center line of the groove bottom surface is oriented in the center line direction of the lower passage opening. Orientation, and the center of the bottom of the concave curved groove surface is a molded surface with no step or raised in the inner surface of the lower passage opening, the lower passage opening is an outlet for residual liquid, and the upper passage opening is a permeated liquid extraction A hollow fiber membrane module having a mouth. 2. The hollow fiber membrane module according to claim 1, wherein the upper resin partition and the upper passage opening are vertically symmetric with respect to the lower resin partition and the lower passage opening.