Smoke analysis characterization cell

Patent metadata

Field	Value
Publication number	US-9733189-B2
Application number	US-201113824712-A
Country	US
Kind code	B2
Filing date	Oct 27, 2011
Priority date	Oct 27, 2010
Publication date	Aug 15, 2017
Grant date	Aug 15, 2017

Abstract

The invention relates to a smoke analysis characterization cell employing optical spectroscopy, which comprises: a reaction chamber, an inlet orifice for injecting smoke into the reaction chamber; an outlet orifice for discharging the smoke from the reaction chamber; and an analysis window for the entry of a laser beam intended to form the plasma inside the reaction chamber, which cell is characterized in that the system further includes a blower for blowing an inert gas close to the analysis window; and a shielding gas injector for the shielded injection of the smoke into the reaction chamber, the shielding being provided by a jet of inert gas around the smoke.

First claim

The invention claimed is:

1. A characterisation system comprising:
a characterisation cell for smoke analysis by optical spectrometry, comprising:
a reaction chamber;
an inlet orifice for the inlet of smoke into the reaction chamber;
an outlet orifice for the evacuation of smoke from the reaction chamber;
an analysis window for entry of a laser beam intended to form the plasma inside the reaction chamber;
a fan for ensuring scanning of inert gas in the vicinity of the analysis window; and
a shielding injector coaxially aligned with the inlet orifice configured to coaxially inject smoke shielded by a jet of inert gas around the smoke into the reaction chamber;

a collector downstream of the outlet orifice of the cell configured to recover the smoke after its analysis;
a pressure regulator for keeping the pressure constant in the reaction chamber of the cell,
wherein the pressure regulator comprises a regulation valve placed downstream of the collector to compensate for a loss of charge due to clogging of filters of the collector,
wherein the regulation valve is connected to a pressure probe placed in the cell for measuring the pressure therein for its servo-control, and
wherein the regulation valve is servo-controlled as a function of the pressure measured inside the cell and which is adapted to open progressively as the collector gets clogged;
a reactor for the generation of smoke;
a second collector positioned downstream of the reactor;
a second regulation valve for regulating the pressure inside the reactor;
wherein the second regulation valve is placed downstream of the second collector,
wherein the second regulation valve is connected to a second pressure probe placed in the reactor for measuring the pressure therein for its servo-control, and
wherein the second regulation valve is servo-controlled as a function of the pressure measured inside the reactor and which is adapted to open progressively as the second collector gets clogged.

2. The system of claim 1 , wherein the cell further comprises an arm extending between the reaction chamber and the analysis window, the arm being formed in two parts of different cross-sections, the larger cross-section part being arranged nearer the analysis window and the smaller cross-section part being arranged nearer the reaction chamber to form a Venturi and to ensure overpressure nearer the window.

3. The system of claim 1 , wherein the flow rate of inert gas generated by the fan is adjustable.

4. The system of claim 1 , wherein the flow rate of inert gas generated by the coaxial shielding injector is adjustable.

5. The system of claim 1 , wherein the injector is a circular double nozzle having first and second coaxial orifices, the first orifice having a disc-shaped cross-section for the inlet of smoke, and the second orifice having a ring-shaped cross-section which encloses the first orifice for the inlet of inert gas.

6. The system of claim 1 , wherein the cell further comprises a viewing window for observation of the plasma produced inside the reaction chamber during its operation.

7. The system of claim 1 , wherein the fan also ensures scanning of inert gas in the vicinity of the viewing window.

8. The system of claim 1 , wherein the flow rate of inert gas generated by the Venturi is adjustable.

9. The system of claim 1 , wherein the cell further comprises an arm extending between the reaction chamber and the inlet orifice.

10. The system of claim 1 , wherein the cell further comprises an arm extending between the reaction chamber and the outlet orifice.

11. The system of claim 1 , wherein the cell further comprises a first arm extending between the reaction chamber and the inlet orifice, a second arm extending between the reaction chamber and the outlet orifice, and a third arm extending between the reaction chamber and the analysis window.

12. The system of claim 11 , wherein the first and second arms extend along a first axis, and the third arm extends along a second axis that is perpendicular to the first axis.

13. The system of claim 11 , wherein the third arm is formed in two parts of different cross-sections, the larger cross-section part being arranged nearer the analysis window and the smaller cross-section part being arranged nearer the reaction chamber to form a Venturi and to ensure overpressure nearer the window.

14. The system of claim 1 , wherein the smoke is a smoke of nanoparticles.

15. The system of claim 1 , wherein the second regulation valve regulates the pressure inside the reactor so as to keep said pressure constant.

16. The system of claim 1 , wherein the second regulation valve is placed at the outlet of the second collector.

17. The system of claim 1 , wherein the second regulation valve is adapted to open progressively as filters of the second collector gets clogged due to nanoparticles.

18. The system of claim 1 , wherein an outlet of the reactor is connected to a pump which creates a flow of smoke.

Assignees

• Maskrot Hicham
• Sirven Jean-Baptiste
• Dewalle Pascale
• Guizard Benoit
• Commissariat Energie Atomique

Inventors

• Maskrot Hicham
• Sirven Jean-Baptiste
• Dewalle Pascale
• Guizard Benoit

Classifications

• G01N2021/151

  Gas blown · CPC title

• G21K1/00

  Arrangements for handling particles or ionising radiation, e.g. focusing or moderating · CPC title

• G01N21/718

  Laser microanalysis, i.e. with formation of sample plasma · CPC title

• G01N21/3504

  for analysing gases, e.g. multi-gas analysis · CPC title

• B01J2219/0875

  Gas · CPC title