Method for collecting uranium by treatment process of washing waste liquid generated in uranium hexafluoride cylinder washing process

Patent metadata

Field	Value
Publication number	US-11289233-B2
Application number	US-201816171641-A
Country	US
Kind code	B2
Filing date	Oct 26, 2018
Priority date	Apr 28, 2016
Publication date	Mar 29, 2022
Grant date	Mar 29, 2022

Abstract

Disclosed are a method and a device for recovering uranium (U) using a process for chemically treating washing wastewater of a uranium hexafluoride (UF6) cylinder. The method and the device are provided to separate uranium (U) from the wastewater released during a process of washing the uranium hexafluoride (UF6) cylinder and to release a filtrate that satisfies atomic energy licensing standards and environmental regulation standards using evaporation and condensation. Accordingly, an independent technology and process for treating the wastewater released during the process of washing the uranium hexafluoride (UF6) cylinder are ensured, which provides easier maintenance and greatly reduces costs compared to the purchase and operation of apparatuses manufactured by foreign makers.

First claim

The invention claimed is:

1. A method of recovering uranium (U) using a process for treating a washing wastewater comprising hydrogen peroxide (H 2 O 2 ), sodium carbonate (Na 2 CO 3 ), and a uranium complex, the washing wastewater released during a washing process of a uranium hexafluoride (UF 6 ) cylinder, the method comprising:
(1) adding sodium hydroxide (NaOH) to the washing wastewater to precipitate the uranium complex, contained in the washing wastewater, in a sodium diuranate (NaDU) form;
(2) separating a sodium diuranate (NaDU) precipitate formed during the step (1) and the washing wastewater using filtration;
(3) evaporating the washing wastewater filtered during the step (2); and
(4) cooling a vapor generated during the step (3) to recover a condensate and then checking remaining amounts of uranium (U) and fluorine (F).

2. The method of claim 1 , wherein a demineralized water or a mixed solution, including the hydrogen peroxide (H 2 O 2 ) and the sodium carbonate-(Na 2 CO 3 ), is used as a washing solution during the washing process of the uranium hexafluoride (UF 6 ) cylinder, causing generation of the washing wastewater.

3. The method of claim 1 , further comprising:
after the step (3),
(5) filtering and evaporating a remaining wastewater after the evaporating of the step (3); and
(6) cooling a vapor generated during the step (5) to recover a condensate and then checking remaining amounts of uranium (U) and fluorine (F).

4. The method of claim 1 , wherein a sodium hydroxide (NaOH) aqueous solution is added while the washing wastewater is heated during the step (1) so that a pH is controlled to form a sodium diuranate (NaDU) solid, thereby performing precipitation.

5. The method of claim 1 , wherein during the step (3), a steam is supplied to evaporate water, the evaporated water is transported through a heat exchanger to a condensate storage tank, and a residue is returned to the step (2).

Assignees

• Bae Youngmoon
• Shin Hyundong
• Yang Seungchul
• Jo Bohyun
• Lee Byungkuk
• Kwak Dongyong
• Cho Hyunkwang
• Gu Sunghoi
• Hwang Euijun
• Kepco Nuclear Fuel Co Ltd

Inventors

• Bae Youngmoon
• Shin Hyundong
• Yang Seungchul
• Jo Bohyun
• Lee Byungkuk
• Kwak Dongyong
• Cho Hyunkwang
• Gu Sunghoi
• Hwang Euijun

Classifications

• C22B60/0278 Primary

  by chemical methods (C22B60/0256, C22B60/026, C22B60/0265 take precedence) · CPC title

• C02F2101/006

  Radioactive compounds · CPC title

• C02F11/10

  by pyrolysis · CPC title

• C02F1/52

  by flocculation or precipitation of suspended impurities {(C02F1/463 takes precedence)} · CPC title

• C02F1/66

  by neutralisation; pH adjustment (for degassing C02F1/20; using ion-exchange C02F1/42; for flocculation or precipitation of suspended impurities C02F1/52; for removing dissolved compounds C02F1/58) · CPC title