Gas analyser

Patent metadata

Field	Value
Publication number	US-9304079-B2
Application number	US-201414302997-A
Country	US
Kind code	B2
Filing date	Jun 12, 2014
Priority date	Dec 15, 2011
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

A gas analyzer for the absorption-spectroscopic in-situ determination of at least one chemical and/or physical parameter of a gaseous measurement medium, wherein the gas analyzer includes a first housing; at least one laser as a radiation source, which laser is arranged in the first housing; at least one first process window for coupling the radiation emitted by the laser into a measurement medium; and at least one detector by which, following interaction with the measurement medium, the radiation is detected. The first process window can be configured as an afocal meniscus lens having a convex surface and a concave surface.

First claim

What is claimed is:

1. A gas analyser for absorption-spectroscopic in-situ determination of at least one chemical and/or physical parameter of a gaseous measurement medium, wherein the gas analyser comprises:
a first housing;
at least one laser as a radiation source, which laser is arranged in the first housing;
at least one first process window for coupling radiation emitted by the laser into a measurement medium; and
at least one detector configured to detect radiation following interaction with the measurement medium wherein the first process window is configured as an afocal meniscus lens having a body, the body having a convex surface and a concave surface opposite the convex surface.

2. The gas analyser according to claim 1 , comprising:
an optical reflector element that reflects radiation coupled into the measurement medium back to the first process window.

3. The gas analyser according to claim 2 , wherein the optical reflector element comprises:
at least one component of cat's eyes optics, at least one triple prism, at least one triple mirror, or at least one planar mirror or imaging mirror.

4. The gas analyser according to claim 3 , wherein the chemical and/or physical parameter to be determined comprise/comprises:
at least one of the following parameters: temperature, pressure and/or a concentration of at least one gas selected from a group consisting of oxygen, carbon dioxide, carbon monoxide, nitrogen oxides, ammonia, amines, hydrogen halides, hydrogen sulphides, sulphur dioxide, water and mixtures thereof.

5. The gas analyser according to claim 2 , wherein the detector and the laser are arranged in the first housing, and the first process window is arranged for coupling radiation when emitted by the laser to a measurement medium and, following interaction with the measurement medium, also for coupling radiation from the measurement medium.

6. The gas analyser according to claim 5 , comprising:
a gas probe having an essentially cylindrical probe body with at least one process opening through which, during operation, a measurement medium can enter into an interior of the probe body, wherein during operation one end of the gas probe is connected to the first housing.

7. The gas analyser according to claim 2 , comprising:
a second housing; and
a second process window, wherein the detector or the optical reflector element is arranged in the second housing; and
a gas probe having an essentially cylindrical probe body with at least one process opening through which, during operation, a measurement medium can enter into an interior of the probe body, wherein during operation one end of the gas probe is connected to the first housing.

8. The gas analyser according to claim 1 , wherein the detector and the laser are arranged in the first housing, and the first process window is arranged for coupling radiation when emitted by the laser to a measurement medium and, following interaction with the measurement medium, also for coupling a radiation from the measurement medium.

9. The gas analyser according to claim 1 , comprising:
a second housing; and
a second process window, wherein the detector is arranged in the second housing.

10. The gas analyser according to claim 9 , wherein the second process window is configured as an afocal meniscus lens that comprises:
a body having a convex surface and a concave surface opposite the convex surface.

11. The gas analyser according to claim 1 , comprising:
a gas probe having an essentially cylindrical probe body with at least one process opening through which, during operation, a measurement medium can enter into an interior of the probe body, wherein during operation one end of the gas probe is connected to the first housing.

12. The gas analyser according to claim 11 , wherein the gas probe comprises:
a purge-gas connection for a purge gas; and
at least one purge-gas line.

13. The gas analyser according to claim 12 , configured such that during operation the first process window and/or the second process windows/window will comprise:
a purge-gas cushion on a side of a measurement medium.

14. The gas analyser according to claim 1 , wherein the first process window is a non-coated process window or has no anti-reflection coating.

15. A gas analyser for absorption-spectroscopic in-situ determination of at least one chemical and/or physical parameter of a gaseous measurement medium, wherein the gas analyser comprises:
a first housing;
at least one laser as a radiation source, which laser is arranged in the first housing;
at least one first process window for coupling radiation emitted by the laser into a measurement medium; and
at least one detector configured to detect radiation following interaction with the measurement medium wherein the first process window is configured as an afocal meniscus lens having a convex surface and a concave surface;
an optical reflector element that reflects radiation coupled into the measurement medium back to the first process window; and
wherein the optical reflector element is attached without a seal, and arranged such that, during operation, purge gas will flow around the reflector element.

16. The gas analyser according to claim 15 , wherein the laser is a tunable laser.

17. The gas analyser according to claim 15 , wherein the chemical and/or physical parameter to be determined comprise/comprises:
at least one of the following parameters: temperature, pressure and/or a concentration of at least one gas selected from a group consisting of oxygen, carbon dioxide, carbon monoxide, nitrogen oxides, ammonia, amines, hydrogen halides, hydrogen sulphides, sulphur dioxide, water and mixtures thereof.

18. The gas analyser according to claim 15 , comprising:
a second housing; and
a second process window, wherein the detector or the optical reflector element is arranged in the second housing.

19. The gas analyser according to claim 15 , comprising:
a gas probe having a generally cylindrical probe body with at least one process opening through which, during operation, a measurement medium can enter into an interior of the probe body, wherein during operation one end of the gas probe is connected to the first housing.

20. A gas analyser for absorption-spectroscopic in-situ determination of at least one chemical and/or physical parameter of a gaseous measurement medium, wherein the gas analyser comprises:
a first housing;
at least one laser as a radiation source, which laser is arranged in the first housing;
at least one first process window for coupling radiation emitted by the laser into a measurement medium; and
at least one detector configured to detect radiation following interaction with the measurement medium wherein the first process window is configured as an afocal meniscus lens having a convex surface and a concave surface;
an optical reflector element that reflects radiation coupled into the measurement medium back to the first process window;
a second housing; and
a second process window, wherein the detector or the optical reflector element is arranged in the second housing;
a gas probe having an essentially cylindrical probe body with at least one process opening through which, during operation, a measurement medium can enter into an interior of the probe body, wherein during operation one end of the gas probe is connected to the first housing; and
wherein the optical reflector element is attached without a seal, and arrange such that, during operation, purge gas will flow around t

Assignees

• Mettler Toledo Ag
• Mettler Toledo Gmbh

Inventors

• Killich Frank

Classifications

• G01N21/3504 Primary

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

• G01N21/8507

  Probe photometers, i.e. with optical measuring part dipped into fluid sample · CPC title

• G01N21/39 Primary

  using tunable lasers · CPC title

• G01N2021/151

  Gas blown · CPC title

• G01N2021/8514

  with immersed mirror · CPC title