JPH112605A - Directly analyzing method of gas using laser - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a directly analyzing method of gas through the use of laser capable of detecting the component composition, the plasma temperature, and the concentration of the minor component of a part to be measured in a power plant, etc., online. SOLUTION: An optical window 6 is provided for a piping 1, etc., of various plants. While laser for plasma is reflected at a mirror 15 through a lens 4, then projected from the optical window 6, and converged to a part to be measured 2 in the piping 1, etc., to turn gases and solids at the part to be measured 2 into plasma, plasma emission and fluorescence emitted by the part to be measured 2 are detected at a CCD camera 12 through the mirror 15 and a spectrograph 11. By detected plasma signals, the component composition, the plasma temperature, and the concentration of the minor component of the part to be measured 2 are detected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for directly analyzing gas using a laser in a power plant or the like.

[0002]

2. Description of the Related Art Conventionally, gas concentrations in pipes and ducts in power generation plants and the like can be measured on-line by gas chromatography for main gas components. The composition of the powder contained in the sample was analyzed after inhaling the gas and the powder, and it was difficult to perform online measurement.

[0003] In addition, if the distribution of gas and powder in the pipe is biased, there is a possibility that the measured value obtained does not show an accurate value. Furthermore, in order to measure the temperature and concentration distribution in pipes and ducts, there is no other way but to use multiple sampling positions in pipes and ducts or to traverse the sampling positions. there were.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above prior art, and uses a laser capable of detecting, on-line, the component composition, plasma temperature, and trace component concentration of a part to be measured in a power plant or the like. To provide a direct analysis method of the gas that was used.

[0005]

According to the present invention for achieving the above object, an optical window is provided in piping of various plants, a plasma laser is reflected by a mirror through a lens, and then projected from the optical window. While condensing on the measured part in the pipe or the like and converting gas and solid in the measured part into plasma, plasma emission and fluorescent light emitted by the measured part are transmitted to a CCD camera via a mirror and a spectroscope. And detect
The composition of the component to be measured, the plasma temperature, and the concentration of the trace component are detected based on the detected plasma signal.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. 1 shows an example of an analyzer using a laser according to an embodiment of the present invention. As shown in FIG.
A laser 3 for plasma (laser for generating laser-induced plasma in the measurement field) is passed through a lens 4 to a measurement field 2 in the inside, reflected by a mirror 15, and then purged.
Through the attached optical window 6, the light is condensed on the portion to be measured 2 and the gas and solid existing there are turned into plasma.

In synchronism with the plasma laser 3, the output of the component excitation laser 7 (laser transmitting a wavelength corresponding to the excitation wavelength of the component to be measured in the substance) is output to the mirror 8 and the lens 4.
And into the laser-induced plasma via the mirror 15. The plasma emission and the fluorescence emitted from the component to be measured excited by the component excitation laser light are reflected by the mirror 1
The light is condensed by the lens 10 through the mirror 5 and the mirror 9, enters the spectroscope 11, and is detected by the CCD camera 12.

The respective signals are transferred to the computer 13 to determine the component composition and the plasma temperature of the field 2 to be measured from the signal of the plasma emission, correct the fluorescence intensity from the information, and determine the trace components existing in the field to be measured. The concentration of is detected. A line 14 synchronizes the transmission of the plasma laser 3 and the component excitation laser 7 with the CCD camera 12.

In the analyzer of the present embodiment having the above configuration, the position of the lens 4 is adjusted in the direction of the optical axis as shown by the arrow in FIG. Can be changed. Also,
By adjusting the angle of the mirror 15 back and forth as indicated by the arrow in the figure, the focal position of the laser beam in the measurement site 2 can be changed.

[0010] Thus, by measuring while changing the position of the laser beam, and by averaging those measurement results,
More accurate temperature and concentration in the pipe 1 can be obtained. Also, by changing the measurement position in the measurement site 2 within a cross section perpendicular to the flow direction of the pipe 1,
It is possible to measure the concentration distribution and the temperature distribution in the same section of the pipe 1 in a short time.

As described above, according to this embodiment, by changing the focal position of the laser beam, the measurement position in the measurement target field 2 can be changed, and the average temperature and average concentration in that area can be obtained. it can. Further, the temperature distribution and the concentration distribution can be measured in a short time by changing the measurement position in the measurement site 2 within a cross section perpendicular to the flow direction of the pipe 1 and performing measurement.

[Embodiment 2] FIG. 2 shows an outline of an apparatus using a laser according to another embodiment of the present invention. As shown in the drawing, the laser 3 is passed through a lens 4 having a mechanism for moving the laser 3 in a direction parallel to the incident direction of the laser beam, and is reflected by a mirror 15 having a mechanism for changing the reflection direction with respect to the incident direction. Collect light.

By moving the position of the lens 4 back and forth, the distance from the laser 3 to the focus 2 can be changed. Further, by changing the angle of the mirror 15 with respect to the laser 3, the irradiation position of the laser beam can be changed. As described above, according to the apparatus according to the present embodiment, the focal position of the laser beam can be adjusted to the target position, and the focal position can be freely moved within a certain range.

[0014]

As described above in detail with reference to the embodiments, the present invention provides an optical window in piping of various plants, reflects a plasma laser through a lens through a mirror, and then sets the optical window. While projecting from a window, the light is condensed on the measured portion in the pipe or the like, and the gas and solid in the measured portion are turned into plasma, while the plasma emission and the fluorescence emitted by the measured portion are mirrored, Through the detected plasma signal, a component composition, a plasma temperature and a trace component concentration of the measured portion can be detected on-line based on the detected plasma signal.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing an embodiment of an analyzer using a laser according to the present invention.

FIG. 2 is a conceptual diagram of another embodiment of the apparatus using the laser of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe 2 Measurement field 3 Plasma laser 4 Lens 5 Purge 6 Optical window 7 Component excitation laser 8 Mirror 9 Mirror 10 Lens 11 Spectroscope 12 CCD camera 13 Computer 14 Synchronization line 15 Mirror

Claims (1)

[Claims] An optical window is provided in a pipe or the like of various plants, and a laser for plasma is reflected by a mirror through a lens, and then is projected from the optical window and condensed on a portion to be measured in the pipe or the like. While the gas and the solid in the measured part are turned into plasma, the plasma emission and the fluorescence emitted from the measured part are detected by a CCD camera via a mirror and a spectroscope, and the measured plasma signal is used. A direct gas analysis method using a laser, comprising detecting a component composition, a plasma temperature, and a trace component concentration of a part.