Invention Grant
- Patent Title: Hydrofluoric acid wastewater treatment method and device
- Patent Title (中): 氢氟酸废水处理方法及装置
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Application No.: US10722990Application Date: 2003-11-26
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Publication No.: US07311799B2Publication Date: 2007-12-25
- Inventor: Junji Mizutani , Mitsuo Maeda , Tamito Mukaida , Yasushi Nishimura , Yutaka Shiomi , Koji Harada , Yoshio Tanimoto , Toshiaki Muratani
- Applicant: Junji Mizutani , Mitsuo Maeda , Tamito Mukaida , Yasushi Nishimura , Yutaka Shiomi , Koji Harada , Yoshio Tanimoto , Toshiaki Muratani
- Applicant Address: JP Osaka-Shi JP Osaka-Shi
- Assignee: Sasakura Engineering Co., Ltd.,Sharp Kabushiki Kaisha
- Current Assignee: Sasakura Engineering Co., Ltd.,Sharp Kabushiki Kaisha
- Current Assignee Address: JP Osaka-Shi JP Osaka-Shi
- Agency: Knobbe Martens Olson & Bear LLP
- Priority: JP2002-346465 20021128
- Main IPC: B01D1/00
- IPC: B01D1/00

Abstract:
The invention provides a hydrofluoric acid wastewater treatment method that achieves efficient recovery of hydrofluoric acid from hydrofluoric acid wastewater and also achieves sufficient reduction in the hydrofluoric acid concentration of the dehydrofluorinated water after treatment.The hydrofluoric acid wastewater treatment method comprises the following steps: a hydrofluoric acid concentration step (S1) comprising concentrating hydrofluoric acid wastewater by evaporation to produce a concentrated hydrofluoric acid water and a hydrofluoric acid-containing vapor; a dissolution step (S2) comprising bringing the hydrofluoric acid-containing vapor obtained in the hydrofluoric acid concentration step (S1) into contact with dissolution water to dissolve the vapor; a neutralization step (S3) comprising bringing the residual hydrofluoric acid-containing vapor left from the dissolution step (S2) into contact with an alkali to produce a neutralized liquid and a dehydrofluorinated vapor; and a condensation step (S4) comprising condensing the dehydrofluorinated vapor obtained in the neutralization step (S3) to produce condensed water.
Public/Granted literature
- US20040104107A1 Hydrofluoric acid wastewater treatment method and device Public/Granted day:2004-06-03
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