Device for producing fluorine gas and light scattering detector

Patent metadata

Field	Value
Publication number	US-12163235-B2
Application number	US-202017614801-A
Country	US
Kind code	B2
Filing date	Dec 3, 2020
Priority date	Dec 27, 2019
Publication date	Dec 10, 2024
Grant date	Dec 10, 2024

Abstract

A device for producing fluorine gas has a first flow path configured to send a fluid from the inside of an electrolytic cell through a mist removal unit configured to remove mist from the fluid to a fluorine gas selection unit and a second flow path configured to send the fluid from the inside of the electrolytic cell to the fluorine gas selection unit without passing through the mist removal unit and has a flow path switching unit configured to switch a flow path through which the fluid flows depending on the average particle size of the mist measured by an average particle size measurement unit. The second flow path has a clogging suppression mechanism configured to suppress clogging of the second flow path by the mist.

First claim

The invention claimed is:

1. A device for producing fluorine gas in which an electrolyte containing hydrogen fluoride and a metal fluoride is electrolyzed to produce fluorine gas, the device comprising:
an electrolytic cell storing the electrolyte and configured to perform the electrolysis;
an average particle size measurement unit configured to measure an average particle size of mist contained in a fluid generated inside the electrolytic cell during the electrolysis of the electrolyte;
a mist removal unit configured to remove the mist from the fluid;
a fluorine gas selection unit configured to select and extract fluorine gas from the fluid; and
a flow path configured to send the fluid from an inside of the electrolytic cell to the fluorine gas selection unit,
wherein the flow path has a first flow path configured to send the fluid from the inside of the electrolytic cell through the mist removal unit to the fluorine gas selection unit and a second flow path configured to send the fluid from the inside of the electrolytic cell to the fluorine gas selection unit without passing through the mist removal unit and has a flow path switching unit configured to switch a flow path through which the fluid flows depending on the average particle size of the mist measured by the average particle size measurement unit,
the flow path switching unit is configured to send the fluid to the first flow path from the inside of the electrolytic cell in a case where the average particle size of the mist measured by the average particle size measurement unit is equal to or less than a predetermined reference value and to send the fluid to the second flow path from the inside of the electrolytic cell in a case where the average particle size of the mist is more than the predetermined reference value, and
the second flow path has a clogging suppression mechanism configured to suppress clogging of the second flow path by the mist.

2. The device for producing fluorine gas according to claim 1 , wherein the average particle size measurement unit measures an average particle size of mist contained in a fluid generated at an anode of the electrolytic cell.

3. The device for producing fluorine gas according to claim 2 , wherein the clogging suppression mechanism is a pipe having a larger diameter than the first flow path.

4. The device for producing fluorine gas according to claim 2 , wherein the clogging suppression mechanism is a pipe inclined with respect to a horizontal direction and extending in a direction in which the pipe runs downward from an upstream side toward a downstream side.

5. The device for producing fluorine gas according to claim 2 , wherein the clogging suppression mechanism is a rotary screw installed inside the second flow path and configured to send the mist accumulated inside the second flow path to an upstream side or a downstream side.

6. The device for producing fluorine gas according to claim 2 , wherein the clogging suppression mechanism is an airflow generator configured to cause an airflow for increasing a flow rate of the fluid flowing in the second flow path to flow.

7. The device for producing fluorine gas according to claim 2 , wherein
the average particle size measurement unit includes a light scattering detector,
the light scattering detector includes
a sample chamber configured to store the fluid,
a light source configured to irradiate the fluid in the sample chamber with light for light scattering measurement,
a scattered light detection unit configured to detect scattered light generated by scattering of the light for light scattering measurement by the mist, and
a transparent window installed in the sample chamber to come into contact with the fluid and configured to transmit the light for light scattering measurement or the scattered light, and

the transparent window is formed of at least one selected from diamond, calcium fluoride, potassium fluoride, silver fluoride, barium fluoride, and potassium bromide.

8. The device for producing fluorine gas according to claim 1 , wherein the clogging suppression mechanism is a pipe having a larger diameter than the first flow path.

9. The device for producing fluorine gas according to claim 8 , wherein the clogging suppression mechanism is a pipe inclined with respect to a horizontal direction and extending in a direction in which the pipe runs downward from an upstream side toward a downstream side.

10. The device for producing fluorine gas according to claim 8 , wherein
the average particle size measurement unit includes a light scattering detector,
the light scattering detector includes
a sample chamber configured to store the fluid,
a light source configured to irradiate the fluid in the sample chamber with light for light scattering measurement,
a scattered light detection unit configured to detect scattered light generated by scattering of the light for light scattering measurement by the mist, and
a transparent window installed in the sample chamber to come into contact with the fluid and configured to transmit the light for light scattering measurement or the scattered light, and

the transparent window is formed of at least one selected from diamond, calcium fluoride, potassium fluoride, silver fluoride, barium fluoride, and potassium bromide.

11. The device for producing fluorine gas according to claim 1 , wherein the clogging suppression mechanism is a pipe inclined with respect to a horizontal direction and extending in a direction in which the pipe runs downward from an upstream side toward a downstream side.

12. The device for producing fluorine gas according to claim 11 , wherein
the average particle size measurement unit includes a light scattering detector,
the light scattering detector includes
a sample chamber configured to store the fluid,
a light source configured to irradiate the fluid in the sample chamber with light for light scattering measurement,
a scattered light detection unit configured to detect scattered light generated by scattering of the light for light scattering measurement by the mist, and
a transparent window installed in the sample chamber to come into contact with the fluid and configured to transmit the light for light scattering measurement or the scattered light, and

the transparent window is formed of at least one selected from diamond, calcium fluoride, potassium fluoride, silver fluoride, barium fluoride, and potassium bromide.

13. The device for producing fluorine gas according to claim 1 , wherein the clogging suppression mechanism is a rotary screw installed inside the second flow path and configured to send the mist accumulated inside the second flow path to an upstream side or a downstream side.

14. The device for producing fluorine gas according to claim 13 , wherein
the average particle size measurement unit includes a light scattering detector,
the light scattering detector includes
a sample chamber configured to store the fluid,
a light source configured to irradiate the fluid in the sample chamber with light for light scattering measurement,
a scattered light detection unit configured to detect scattered light generated by scattering of the light for light scattering measurement by the mist, and
a transparent window installed in the sample chamber to come into contact with the fluid and configured to transmit the light for light scattering measurement or the scattered light, and

the transparent window is formed of at least one selected from diamond, calcium fluoride, potassium fluoride, silver fluoride, barium fluoride, and potassium bromide.

15. The device

Assignees

• Showa Denko Kk
• Resonac Corp

Inventors

• Mikami Katsumi
• FUKUCHI Yohsuke
• Kobayashi Hiroshi

Classifications

• G01N2015/0277

  Average size only · CPC title

• G01N15/0211

  Investigating a scatter or diffraction pattern · CPC title

• C25B15/023

  Measuring, analysing or testing during electrolytic production · CPC title

• C25B9/09

  Fused bath cells · CPC title

• C25B9/00

  Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features · CPC title