Hydrophilic treatment method of reverse osmosis membrane

A technology of reverse osmosis membrane and treatment method, applied in the field of hydrophilization treatment agent, which can solve the problems of peeling, loss of hydrophilization effect, and decrease of RO membrane flux, and achieve the effect of easy modulation

Active Publication Date: 2017-03-22
KURITA WATER INDUSTRIES LTD
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] In the hydrophilization treatment of the conventional RO membrane using PVA, there are the following problems: (1) PVA will peel off from the RO membrane during long-term use, and the hydrophilization effect will be lost; (2) PVA will adhere to the RO membrane, As a result, the flux of the RO membrane decreased significantly compared to before the attachment

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Hydrophilic treatment method of reverse osmosis membrane

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0057] The Nitto Denko RO membrane "ES20" (flat membrane, diameter 32 mmφ) was subjected to a hydrophilic treatment under the following conditions. Modified polyvinyl alcohol having a polyalkylene oxide chain, which is a hydrophilizing agent, was used by dissolving in ultrapure water (60°C). After the hydrophilization treatment, the biologically treated water from the drainage recovery device of the Kurita Industrial Co., Ltd. Development Center was used to conduct a water flow test to verify the flux stability.

[0058] 〈Hydrophilic treatment〉

[0059] Hydrophilic treatment agent: "ECOMATY WO-320N" manufactured by Nippon Synthetic Chemical Industry Co., Ltd. (modified polyvinyl alcohol having a polyethylene oxide chain, saponification degree of 98.5% or more)

[0060] Concentration: 100mg / L

[0061] Water time: 5 hours

[0062] Inlet pressure: 0.75MPa

[0063] Flux: 1.0m / day

[0064] Water temperature: 25°C

[0065] 〈Water penetration test〉

[0066] Water flow evaluati...

Embodiment 2

[0072] Except using "ECOMATY WO-320R" (modified polyvinyl alcohol having a polyethylene oxide chain, saponification degree 86.5-89.5%) manufactured by Nippon Synthetic Chemical Industry Co., Ltd., the same test as in Example 1 was carried out. Quantitative stability. The results are shown in figure 1 .

Embodiment 3

[0074] Except that the inlet pressure during the hydrophilization treatment was set to 0.2 MPa, the same test as in Example 1 was carried out to examine flux stability. The results are shown in figure 1 .

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
concentrationaaaaaaaaaa
recovery rateaaaaaaaaaa
Login to view more

Abstract

Provided is a method for hydrophilizing an RO membrane, the method being excellent in terms of the persistence of the hydrophilization effect and flux stability. An RO membrane is brought into contact with a modified polyvinyl alcohol having a polyalkylene oxide chain. The modified polyvinyl alcohol has a degree of saponification of preferably 80% or higher, and the polyalkylene oxide chain preferably is a polyethylene oxide chain. The modified polyvinyl alcohol having a polyalkylene oxide chain has higher adsorbability onto RO membranes than conventional PVAs, and the antifouling properties can hence be maintained over a long period.

Description

technical field [0001] The present invention relates to a hydrophilization treatment method of a reverse osmosis (RO) membrane using modified polyvinyl alcohol having a polyalkylene oxide chain, an RO membrane hydrophilized using the method, and a hydrophilization treatment method of the RO membrane. Hydration agent. Background technique [0002] RO membranes are widely used in various water treatment fields for the purpose of desalination and concentration in order to take advantage of their characteristics. [0003] Conventionally, in order to prevent the reduction of the permeated water (flux) and the reduction of the salt rejection rate of the RO membrane due to use, a method of contacting the RO membrane with polyvinyl alcohol (PVA) has been known (for example, Patent Documents 1 to 2). 3). [0004] By bringing PVA into contact with the RO membrane, the RO membrane is hydrophilized and the permeability of the RO membrane is maintained. That is, PVA has high hydrophil...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): B01D67/00B01D61/02C09K3/00
CPCB01D69/02B01D61/025B01D65/08B01D67/0088B01D71/56B01D2323/02B01D2325/36
Inventor 早川邦洋川胜孝博
Owner KURITA WATER INDUSTRIES LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products