Title:
WASTEWATER TREATMENT METHOD
Document Type and Number:
WIPO Patent Application WO/2019/131827
Kind Code:
A1
Abstract:
Provided is a waste liquid treatment method comprising: an aluminum dissolution step of dissolving aluminum in an acidic waste liquid and separating into a first treated water and a heavy metal reduced precipitate; a gypsum recovery step of adding a calcium compound at a pH of 4 or less to the first treated water and separating into a second treated water and gypsum; a heavy metal coprecipitation step of adding a ferric compound to the second treated water and separating into a third treated water and a heavy metal co-precipitate; an aluminum and fluorine removal step of adding an alkali to the third treated water and separating into a fourth treated water and a deposit including aluminum and fluorine; and a neutralization step of adding an alkali to the fourth treated water and separating into alkali-neutralized treated water and a neutralized deposit of heavy metal hydroxides.
Inventors:
HARAGUCHI DAISUKE (JP)
HAYASHI HIROSHI (JP)
HAYASHI HIROSHI (JP)
Application Number:
PCT/JP2018/048026
Publication Date:
July 04, 2019
Filing Date:
December 27, 2018
Export Citation:
Assignee:
MITSUBISHI MATERIALS CORP (JP)
International Classes:
C01F11/46; C02F1/58; C02F1/28; C02F1/62; C02F1/70; C22B3/44; C22B3/46
Foreign References:
JP2018079439A | 2018-05-24 | |||
JPS62197192A | 1987-08-31 | |||
JP2005270860A | 2005-10-06 | |||
JP2016191119A | 2016-11-10 | |||
JP2007196177A | 2007-08-09 | |||
JP2000117265A | 2000-04-25 | |||
JP2017159222A | 2017-09-14 | |||
JP2017250886A | 2017-12-27 | |||
JPS626287B2 | 1987-02-10 | |||
JP2017105651A | 2017-06-15 | |||
JPS5934644B2 | 1984-08-23 | |||
JPH09192675A | 1997-07-29 |
Other References:
See also references of EP 3733612A4
Attorney, Agent or Firm:
MATSUNUMA Yasushi et al. (JP)
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