Title:
METHOD FOR WASHING FILTER AND METHOD FOR DESALINATING SEAWATER
Document Type and Number:
WIPO Patent Application WO/2019/216326
Kind Code:
A1
Abstract:
This method is for washing a filter and is used in a seawater desalination process including a first filtration step for subjecting seawater 3 to microfiltration or ultrafiltration, and a second filtration step for subjecting seawater 4 after the first filtration step to a reverse osmosis treatment, wherein: the filter is a microfiltration membrane or ultrafiltration membrane 41 used in the first filtration step; an iron compound is added to seawater 3 in any stage in the washing method; the washing method includes a washing chemical liquid preparation step for preparing washing chemical liquid 1, and a sticking matter removal step for removing matter sticking to the filter by bringing the filter into contact with washing chemical liquid 1; and in the washing chemical liquid preparation step, seawater 4 after the first filtration step is mixed with at least hydrogen peroxide to prepare washing chemical liquid 1 having an iron compound concentration of 1.50 mmol/L or more in terms of iron atoms.
Inventors:
GOJO YUTAKA (JP)
YOSHIDA TAKAHIDE (JP)
YOSHIDA TAKAHIDE (JP)
Application Number:
PCT/JP2019/018295
Publication Date:
November 14, 2019
Filing Date:
May 07, 2019
Export Citation:
Assignee:
ASAHI CHEMICAL IND (JP)
International Classes:
B01D65/06; B01D21/01; B01D61/04; B01D61/14; B01D61/58; C02F1/44; C11D7/10; C11D7/18; C11D7/26
Domestic Patent References:
| WO2015083717A1 | 2015-06-11 | |||
| WO2008120509A1 | 2008-10-09 |
Foreign References:
| JP2008508093A | 2008-03-21 | |||
| EP1652571A1 | 2006-05-03 |
Attorney, Agent or Firm:
AOKI, Atsushi et al. (JP)
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