Title:
METHOD FOR PRODUCING PURE WATER FROM WHICH BORON HAS BEEN REMOVED, PURE WATER PRODUCTION DEVICE, AND ULTRAPURE WATER PRODUCTION SYSTEM
Document Type and Number:
WIPO Patent Application WO/2024/075731
Kind Code:
A1
Abstract:
Provided are a pure water production device and a pure water production method with which it is possible to suppress scale blockage on a reverse osmosis membrane, whereby pure water can be produced stably and efficiently for an extended period. In this pure water production method for passing raw water through two or more reverse osmosis membranes in sequence to obtain pure water from which boron has been removed, an alkali treatment step and an acid treatment step are performed in a prescribed sequence, the alkali treatment step involving passing alkaline water being treated through one reverse osmosis membrane and the acid treatment step involving passing acidic water being treated through another reverse osmosis membrane. A first treatment period in which a first reverse osmosis membrane is used in the alkali treatment step and a second reverse osmosis membrane is used in the acid treatment step, and a second treatment period in which the second reverse osmosis membrane is used in the alkali treatment step and the first reverse osmosis membrane is used in the acid treatment step, are repeated at prescribed intervals by switching the first reverse osmosis membrane and the second reverse osmosis membrane.
Inventors:
NOGUCHI YUKIO (JP)
YAMADA KENGO (JP)
YAMADA KENGO (JP)
Application Number:
PCT/JP2023/036068
Publication Date:
April 11, 2024
Filing Date:
October 03, 2023
Export Citation:
Assignee:
NOMURA MICRO SCIENCE KK (JP)
International Classes:
C02F1/44; B01D61/04; B01D61/12; B01D61/44; B01D61/58; B01D65/08; B01D69/00
Foreign References:
| JPH11128923A | 1999-05-18 | |||
| JP2013086049A | 2013-05-13 | |||
| JP2000271569A | 2000-10-03 | |||
| JP2014226642A | 2014-12-08 |
Attorney, Agent or Firm:
KOBAYASHI TAKUMI (JP)
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