Hollow fiber membrane module

Patent metadata

Field	Value
Publication number	US-10974199-B2
Application number	US-201716305540-A
Country	US
Kind code	B2
Filing date	May 30, 2017
Priority date	May 31, 2016
Publication date	Apr 13, 2021
Grant date	Apr 13, 2021

Abstract

This hollow fiber membrane module is provided with: a cylindrical case having a first end and a second end in the direction of height; a plurality of hollow fiber membranes accommodated in the cylindrical case; and a first potting unit attaching the end parts of the plurality of hollow fiber membranes positioned at the first end of the cylindrical case while the end parts are open. The hollow fiber membranes have a rupture strength of 23 MPa or more. The filling rate for the hollow fiber membranes is 40-80%.

First claim

The invention claimed is:

1. A hollow-fiber membrane module comprising:
a cylindrical case having a first end and a second end in a height direction,
a plurality of hollow-fiber membranes housed in the cylindrical case, and
a first potting part which bonds end parts of the plurality of hollow-fiber membranes located on the first end side of the cylindrical case while letting the end parts be open,
wherein the hollow-fiber membrane has a breaking strength of 23 MPa or more,
wherein a filling ratio of the hollow-fiber membrane is from 40 to 80%,
wherein the hollow-fiber membrane is a hollow-fiber membrane containing a fluororesin-based polymer,
wherein the hollow-fiber membrane has a columnar texture oriented in a longitudinal direction thereof,
wherein a molecular chain in the columnar texture is oriented in the longitudinal direction of the hollow-fiber membrane, and
wherein a Raman orientation parameter ν of the molecular chain is from 1.5 to 4.0:
Raman orientation parameter=( I 1270/ I 840)parallel/( I 1270/ I 840)perpendicular   (1)

wherein:
parallel condition: the longitudinal direction of the hollow-fiber membrane is parallel to a polarization direction;
perpendicular condition: the longitudinal direction of the hollow-fiber membrane is orthogonal to the polarization direction;
I1270 parallel: the intensity of Raman band at 1,270 cm −1 under the parallel condition;
I1270 perpendicular: the intensity of Raman band at 1,270 cm −1 under the perpendicular condition;
I840 parallel: the intensity of Raman band at 840 cm −1 under the parallel condition; and
I840 perpendicular: the intensity of Raman band at 840 cm −1 under the perpendicular condition.

2. The hollow-fiber membrane module according to claim 1 , wherein the hollow-fiber membrane module is an external pressure-type hollow-fiber membrane module.

3. The hollow-fiber membrane module according to claim 1 , wherein the columnar texture has a short-side length of from 0.5 to 3 μm and an aspect ratio of the columnar texture is 3 or more.

4. The hollow-fiber membrane module according to claim 1 , wherein a thickness uniformity of the columnar texture is 0.50 or more.

5. A hollow-fiber membrane module comprising:
a cylindrical case having a first end and a second end in a height direction,
a plurality of hollow-fiber membranes housed in the cylindrical case, and
a first potting part which bonds end parts of the plurality of hollow-fiber membranes located on the first end side of the cylindrical case while the end parts being open,
wherein the hollow-fiber membrane has a breaking strength of 25 MPa or more, and a filling ratio of the hollow-fiber membrane is from 41 to 80%,
wherein the hollow-fiber membrane module is a hollow-fiber membrane containing a fluororesin-based polymer,
wherein the hollow-fiber membrane has a columnar texture oriented in a longitudinal direction thereof,
wherein at least a part of molecular chains of the fluororesin-based polymer are oriented in the longitudinal direction of the hollow-fiber membrane, and
wherein in the hollow-fiber membrane, an orientation degree π calculated based on the following formula (2) is 0.4 or more and less than 1.0:
Orientation degree π=(180°− H )/180°  (2)

wherein H is a half-width (°) of a diffraction intensity distribution in a circumferential direction of a wide-angle X-ray diffraction image.

6. The hollow-fiber membrane module according to claim 5 , wherein the hollow-fiber membrane module is an external pressure-type hollow-fiber membrane module.

7. The hollow-fiber membrane module according to claim 5 , wherein the columnar texture has a short-side length of from 0.5 to 3 μm and an aspect ratio of the columnar texture is 3 or more.

8. The hollow-fiber membrane module according to claim 5 , wherein a thickness uniformity of the columnar texture is 0.60 or more.

9. The hollow-fiber membrane module according to claim 5 , wherein the half-width H is a half-width of an intensity distribution obtained by circumferentially scanning a crystal peak (2θ=20.4°) derived from a (110) plane of polyvinylidene fluoride in the wide-angle X-ray diffraction measurement.

10. The hollow-fiber membrane module according to claim 5 , wherein when wide-angle X-ray diffraction measurement is performed at measurement points at 1 cm intervals in the longitudinal direction of the hollow-fiber membrane, the orientation degree π is 0.4 or more and less than 1.0 at 80% or more of the measurement points.

Assignees

• Toray Industries

Inventors

• Kobayashi Atsushi
• Iwai Kenta
• Hanakawa Masayuki
• Kitade Tamotsu
• Kimura Masahiro

Classifications

• B01D63/0224 Primary

  Opening the fibre ends after encapsulation · CPC title

• B01D69/08

  Hollow fibre membranes (manufacture of hollow fibres D01D5/24, D01F1/08) · CPC title

• B01D63/04 Primary

  comprising multiple hollow fibre assemblies · CPC title

• B01D71/34

  Polyvinylidene fluoride · CPC title

• B01D65/02

  Membrane cleaning or sterilisation {; Membrane regeneration} · CPC title