CN103592253A - Laser gas analyzer for precise temperature compensation in concentration of gas to be measured - Google Patents
Laser gas analyzer for precise temperature compensation in concentration of gas to be measured Download PDFInfo
- Publication number
- CN103592253A CN103592253A CN201310549646.0A CN201310549646A CN103592253A CN 103592253 A CN103592253 A CN 103592253A CN 201310549646 A CN201310549646 A CN 201310549646A CN 103592253 A CN103592253 A CN 103592253A
- Authority
- CN
- China
- Prior art keywords
- gas
- laser
- measured
- measure
- concentration
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The invention discloses a laser gas analyzer for precise temperature compensation in concentration of gas to be measured. The laser gas analyzer comprises two lasers, wherein the two lasers are both in control connection with a laser driving control circuit; laser emitting ends of the two lasers are respectively accessed into a beam combiner through single-mode optical fibers; a collimating lens is arranged in a light path of a light output end of the beam combiner; a photoelectric conversion receiving end is arranged in a detection gas light path behind the collimating lens, and is connected with a signal processing module; the signal output end of the signal processing module is connected with a time division multiplexing control and data processing unit; the time division multiplexing control and data processing unit is connected with the laser driving control circuit. Due to adoption of the laser gas analyzer, accurate compensation on temperature of the gas to be detected is achieved, the measurement accuracy is greatly improved, and more accurate monitoring data are provided for industrial process control.
Description
Technical field
The present invention relates to a kind of laser gas analyzer that measure gas concentrations is carried out to accurate temperature compensation, be mainly used in the accurate monitoring of commercial production field process gas concentration.
Background technology
Semiconductor laser gas analyser is the gas controlling device of a kind of " in real time ", " online ", is usually used in the fields such as petrochemical industry, iron and steel, cement, environmental protection, industrial on-line monitoring.Laser gas analyzer is a kind of highly sensitive gas analysis means, and its principle is that the laser of specific wavelength passes through after gas, because being subject to the absorption at gas specific absorption peak, produces the decay of light intensity.The available Beer-Lambert law of the decay accurate description of light intensity:
I(v)=I
0(v)exp[-S(T)φ(v)PXL]
I (v) wherein, I
0(v) be respectively that laser passes through after gas, by the light intensity before gas, v swashs light frequency, P, and X and L are respectively pressure, concentration and the light paths of gas.The strong S(T of line) be the function of temperature T, linear function φ (v) represents the shape of absorption line.From Beer-Lambert law, the decay of light intensity and the concentration of tested gas are directly proportional, thereby can obtain by measuring the decay of laser after by gas the concentration of tested gas.Meanwhile, due to the emission peak very narrow (being less than 15MHz) of Distributed Feedback Laser, during work, can select single gas absorption spectrum line to measure, not be subject to the interference of other gases, there is very high measurement sensitivity.
Because laser gas analyzer is a kind of optical monitoring method based on Beer-Lambert law, so its measurement result can be with the absorption intensity of absorption peak of gas, the change of peak shape produces error.Can there is with the change of gas temperature variation clearly in the absorption intensity at gas absorption peak and peak shape, as the absorption peak of ammonia only has half left and right of absorption peak strength under normal temperature when 180 spend, and the temperature of actual ammonia measure field at 180 degree within the scope of 350 degree, so the very large error that the temperature of on-the-spot ammonia gas can cause ammonia concentration to measure.
Gas absorption peak intensity and absorption peak shape variation with temperature situation can be derived by theory, obtain with actual gas peak shape and change very approaching theoretical value.But coming from, the greatest problem that in actual applications, the Measurement accuracy of gas concentration exists cannot obtain gas temperature to be measured accurately.At present, generally use the gas temperature of thermocouple monitoring measurement point, by 4-20mA signal, be transferred to laser gas analyzer, and in instrument internal, the concentration of measuring is carried out to temperature compensation.But thermopair can only be measured the gas temperature of single-point, and laser gas analyzer is the mean concentration of measuring along a line of optical path, and the two exists error.And, for some scenes, very violent along the variation of optical path temperature, several Baidu that gas temperature to be measured can change center from tens degree at edge.Under this condition, there is very large error in spot measurement temperature, and last measurement of concetration result is difficult to truly reflect actual conditions.
Utilize technology development recent years of laser gas analyzer measurement gas temperature rapider.The different absorption peak of same substance is because its absorption peak characteristic is different, and absorption peak variation with temperature characteristic is also different, so the ratio of two root absorption peak intensities and gas temperature are one to one, as shown in Figure 1.Utilize this specific character, just can utilize laser gas analyzer to monitor the temperature of gas to be measured.
Summary of the invention
The present invention proposes a kind of laser gas analyzer that measure gas concentrations is carried out to accurate temperature compensation, utilize laser gas analyzer can measure along the characteristic of the medial temperature of light path gas to be measured, replace and traditional be transferred to again the mode that laser gas analyzer calculates after utilizing thermocouple measuring temperature, can realize gas concentration measurement to be measured more accurately.
Main contents of the present invention comprise:
A kind of laser gas analyzer that measure gas concentrations is carried out to accurate temperature compensation, it is characterized in that: include two laser instruments, two laser instruments are all connected with laser instrument drive control circuit, the Laser emission end of two laser instruments accesses bundling device by single-mode fiber respectively, in the light path of the light output end of bundling device, be equipped with collimation lens, probe gas light path after collimation lens is provided with opto-electronic conversion receiving end, opto-electronic conversion receiving end connects signal processing module, the signal output part of signal processing module connects time division multiplex and controls and data processing unit, time division multiplex control and data processing unit are connected with described laser instrument Drive and Control Circuit, two described laser instruments are respectively used to measure the concentration of gas to be measured and the temperature of gas to be measured, utilize laser gas analysis technical monitoring along the temperature-averaging value of light path gas to be measured, and be worth gas concentration to be measured is compensated with this, obtain accurately the concentration of gas to be measured.
Described a kind of laser gas analyzer that measure gas concentrations is carried out to accurate temperature compensation, it is characterized in that: utilize in industry a large amount of aqueous vapors that exist as the carrier of measurement gas temperature, the intensity rate of absorption peak of measuring respectively two water of 1397.87nm and 1397.75nm carrys out measurement gas temperature.
Described a kind of laser gas analyzer that measure gas concentrations is carried out to accurate temperature compensation, it is characterized in that: described time division multiplex is controlled and data processing unit adopts time-multiplexed mode to carry out work, in the different time, open different laser instruments, measure different components.
Described a kind of laser gas analyzer that measure gas concentrations is carried out to accurate temperature compensation, is characterized in that: two wavelength lasers of described two laser instruments transmitting be respectively 1397nm measure the laser of aqueous vapor with according to measurement gas kind and fixed gas characteristic wavelength laser to be measured.
Principle of the present invention is: owing to generally all there is a large amount of aqueous vapors in industrial process, therefore utilize the temperature of the method gas-monitoring of measuring moisture sorption peak.Adopt the method for wavelength-division multiplex, the wavelength of the wavelength that measure gas concentrations is used and measurement gas temperature is coupled into same light path, so can obtain along optical path gas temperature to be measured accurately, the temperature that utilization measures gas compensates gas concentration, just can obtain gas concentration to be measured accurately.
Advantage of the present invention is:
The present invention has realized the accurate compensation of gas temperature to be measured, has improved greatly measurement accuracy, for industrial process, controls Monitoring Data is more accurately provided.
Accompanying drawing explanation
Fig. 1 is the schematic diagram that laser gas analyzer is measured temperature.
Fig. 2 is the laser gas analyzer structural drawing of accurate temperature compensation.
Fig. 3 is system operation programs process flow diagram.
Embodiment
Below in conjunction with accompanying drawing, by example, the present invention will be further described:
Fig. 2 is the laser gas analyzer structural drawing of accurate temperature compensation.A kind of laser gas analyzer that measure gas concentrations is carried out to accurate temperature compensation, include two laser instruments 1, two laser instruments 1 all with laser instrument Drive and Control Circuit 2 control linkages, the Laser emission end of two laser instruments 1 accesses bundling device 3 by single-mode fiber respectively, in the light path of the light output end of bundling device 3, be equipped with collimation lens 4, probe gas light path 5 after collimation lens 4 is provided with opto-electronic conversion receiving end 6, opto-electronic conversion receiving end 6 connects signal processing module 7, the signal output part of signal processing module 7 connects time division multiplex and controls and data processing unit 8, time division multiplex is controlled and data processing unit 8 is connected with described laser instrument Drive and Control Circuit 2, two described laser instruments 1 are respectively used to measure the concentration of gas to be measured and the temperature of gas to be measured, utilize laser gas analysis technical monitoring along the temperature-averaging value of light path gas to be measured, and be worth gas concentration to be measured is compensated with this, obtain accurately the concentration of gas to be measured.
Utilize in industry a large amount of aqueous vapors that exist as the carrier of measurement gas temperature, the intensity rate of absorption peak of measuring respectively two water of 1397.87nm and 1397.75nm carrys out measurement gas temperature.
Time division multiplex is controlled and data processing unit 8 adopts time-multiplexed mode to carry out work, in the different time, opens different laser instruments, measures different components.
Two wavelength lasers of two laser instruments, 1 transmitting be respectively 1397nm measure the laser of aqueous vapor with according to measurement gas kind and fixed gas characteristic wavelength laser to be measured.
System adopts time-multiplexed mode to work: system drives respectively 1 work of different laser instruments in the different time, measures different components.The laser of two laser instrument 1 outputs is coupled into same light path through the mode of wavelength-division multiplex, then injects gas zones to be measured after the collimation by collimation lens 4, carries out the monitoring of gas.With laser after gas effect through collecting and photoelectric conversion is laggard enters primary control program and carry out the processing of signal.Fig. 3 is system operation programs process flow diagram.As shown in the figure, first, system is switched to the passage of measuring temperature by program, opens the laser works of measuring temperature, stops the laser instrument of measure gas concentrations.After system stability, measure the height at two moisture sorption peaks, then after calculating by algorithm, obtain the medial temperature of gas to be measured.Now, the thermograph of measurement is in laser gas analyzer, in order to using below.After temperature survey completes, system is switched to the passage of measure gas concentrations by program, opens the laser works of measure gas concentrations, stops measuring the laser instrument of temperature.After system stability, the height of measurement gas absorption peak, and by the gas medial temperature to be measured measuring, calculate the accurate concentration of gas to be measured above, then this concentration value is transferred to factory's central control room by means such as display interface, 4-20mA, RS485.Complete thus the concentration monitor of a circulation, system will constantly repeat above-mentioned flow process, to realize the continuous monitoring of gas concentration.
Claims (4)
1. a laser gas analyzer that measure gas concentrations is carried out to accurate temperature compensation, it is characterized in that: include two laser instruments, two laser instruments are all connected with laser instrument drive control circuit, the Laser emission end of two laser instruments accesses bundling device by single-mode fiber respectively, in the light path of the light output end of bundling device, be equipped with collimation lens, probe gas light path after collimation lens is provided with opto-electronic conversion receiving end, opto-electronic conversion receiving end connects signal processing module, the signal output part of signal processing module connects time division multiplex and controls and data processing unit, time division multiplex control and data processing unit are connected with described laser instrument Drive and Control Circuit, two described laser instruments are respectively used to measure the concentration of gas to be measured and the temperature of gas to be measured, utilize laser gas analysis technical monitoring along the temperature-averaging value of light path gas to be measured, and be worth gas concentration to be measured is compensated with this, obtain accurately the concentration of gas to be measured.
2. a kind of laser gas analyzer that measure gas concentrations is carried out to accurate temperature compensation according to claim 1, it is characterized in that: utilize in industry a large amount of aqueous vapors that exist as the carrier of measurement gas temperature, the intensity rate of absorption peak of measuring respectively two water of 1397.87nm and 1397.75nm carrys out measurement gas temperature.
3. a kind of laser gas analyzer that measure gas concentrations is carried out to accurate temperature compensation according to claim 1, it is characterized in that: described time division multiplex is controlled and data processing unit adopts time-multiplexed mode to carry out work, in the different time, open different laser instruments, measure different components.
4. a kind of laser gas analyzer that measure gas concentrations is carried out to accurate temperature compensation according to claim 1 and 2, is characterized in that: two wavelength lasers of two described laser instruments transmittings be respectively 1397nm measure the laser of aqueous vapor with according to measurement gas kind and fixed gas characteristic wavelength laser to be measured.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310549646.0A CN103592253A (en) | 2013-11-06 | 2013-11-06 | Laser gas analyzer for precise temperature compensation in concentration of gas to be measured |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310549646.0A CN103592253A (en) | 2013-11-06 | 2013-11-06 | Laser gas analyzer for precise temperature compensation in concentration of gas to be measured |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103592253A true CN103592253A (en) | 2014-02-19 |
Family
ID=50082479
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310549646.0A Pending CN103592253A (en) | 2013-11-06 | 2013-11-06 | Laser gas analyzer for precise temperature compensation in concentration of gas to be measured |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103592253A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105067564A (en) * | 2015-07-14 | 2015-11-18 | 中国船舶重工集团公司第七一九研究所 | Optical fiber gas concentration detection method with temperature compensation capacity |
| CN108572372A (en) * | 2018-04-24 | 2018-09-25 | 中国科学技术大学 | Time-sharing multiplex F-P etalon Doppler's zero-frequency calibrating installations |
| CN110426978A (en) * | 2019-08-12 | 2019-11-08 | 深圳市泛海三江电子股份有限公司 | Bus type combustible gas detection control circuit, method and device |
| CN114460023A (en) * | 2022-04-14 | 2022-05-10 | 华电智控（北京）技术有限公司 | Detection method, system and device for simultaneously measuring concentrations of multiple gases |
| WO2022174504A1 (en) * | 2021-02-22 | 2022-08-25 | 山东省科学院海洋仪器仪表研究所 | Device and method for detecting vapor concentration using dual lasers |
| WO2022237264A1 (en) * | 2021-05-11 | 2022-11-17 | 华为技术有限公司 | Spectral testing method and system |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0084726B1 (en) * | 1981-12-21 | 1987-01-21 | Exxon Research And Engineering Company | Monitoring gaseous ammonia concentration in flue gases |
| CN1768281A (en) * | 2003-03-31 | 2006-05-03 | 佐勒技术公司 | Method and apparatus for the monitoring and control of combustion |
| CN102183316A (en) * | 2010-12-10 | 2011-09-14 | 中国科学院安徽光学精密机械研究所 | Real-time temperature monitoring instrument for tunable semiconductor laser absorption spectrum |
| CN102654455A (en) * | 2012-04-12 | 2012-09-05 | 安徽皖仪科技股份有限公司 | Laser gas analyzer for multicomponent multiplexing measurement |
-
2013
- 2013-11-06 CN CN201310549646.0A patent/CN103592253A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0084726B1 (en) * | 1981-12-21 | 1987-01-21 | Exxon Research And Engineering Company | Monitoring gaseous ammonia concentration in flue gases |
| CN1768281A (en) * | 2003-03-31 | 2006-05-03 | 佐勒技术公司 | Method and apparatus for the monitoring and control of combustion |
| CN102183316A (en) * | 2010-12-10 | 2011-09-14 | 中国科学院安徽光学精密机械研究所 | Real-time temperature monitoring instrument for tunable semiconductor laser absorption spectrum |
| CN102654455A (en) * | 2012-04-12 | 2012-09-05 | 安徽皖仪科技股份有限公司 | Laser gas analyzer for multicomponent multiplexing measurement |
Non-Patent Citations (4)
| Title |
|---|
| M.A. BOLSHOV ET AL.: "Measurements of the temperature and water vapor concentration", 《APPL PHYS B》 * |
| TINGDONG CAI等: "A sensor for measurements of temperature and water concentration using a", 《SENSORS AND ACTUATORS A》 * |
| 张志荣等: "基于TDLAS 方法的高温管道温度与氧气浓度测量机理研究", 《中国光学学会2010年光学大会论文集》 * |
| 束小文等: "基于TDLAS技术的HCl气体在线探测温度补偿方法研究", 《光谱学与光谱分析》 * |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105067564A (en) * | 2015-07-14 | 2015-11-18 | 中国船舶重工集团公司第七一九研究所 | Optical fiber gas concentration detection method with temperature compensation capacity |
| CN105067564B (en) * | 2015-07-14 | 2017-10-13 | 中国船舶重工集团公司第七一九研究所 | A kind of optical fiber gas concentration detection method with temperature compensation capability |
| CN108572372A (en) * | 2018-04-24 | 2018-09-25 | 中国科学技术大学 | Time-sharing multiplex F-P etalon Doppler's zero-frequency calibrating installations |
| CN108572372B (en) * | 2018-04-24 | 2020-10-27 | 中国科学技术大学 | Time-sharing multiplexing F-P etalon Doppler zero frequency calibration device |
| CN110426978A (en) * | 2019-08-12 | 2019-11-08 | 深圳市泛海三江电子股份有限公司 | Bus type combustible gas detection control circuit, method and device |
| CN110426978B (en) * | 2019-08-12 | 2024-04-02 | 深圳市高新投三江电子股份有限公司 | Bus type combustible gas detection control circuit, method and device thereof |
| WO2022174504A1 (en) * | 2021-02-22 | 2022-08-25 | 山东省科学院海洋仪器仪表研究所 | Device and method for detecting vapor concentration using dual lasers |
| WO2022237264A1 (en) * | 2021-05-11 | 2022-11-17 | 华为技术有限公司 | Spectral testing method and system |
| CN114460023A (en) * | 2022-04-14 | 2022-05-10 | 华电智控（北京）技术有限公司 | Detection method, system and device for simultaneously measuring concentrations of multiple gases |
| CN114460023B (en) * | 2022-04-14 | 2022-08-05 | 华电智控（北京）技术有限公司 | Detection method, system and device for simultaneously measuring concentration of multiple gases |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103592253A (en) | Laser gas analyzer for precise temperature compensation in concentration of gas to be measured | |
| CN205374298U (en) | Trace gas concentration detection apparatus based on TDLAS | |
| CN101441173B (en) | Laser absorption spectrum trace amount gas analysis method and apparatus using the same | |
| CN101504367B (en) | Apparatus for simultaneously monitoring concentration of carbon monoxide and carbon dioxide | |
| CN204924934U (en) | Multicomponent gas is detection device simultaneously based on two kinds of quantum cascade laser spectrum | |
| CN201163269Y (en) | Laser absorptive spectrum trace amount gas analyzer | |
| CN105277503A (en) | Two quantum cascade laser spectrum-based multicomponent gas simultaneous detection device and method | |
| CN102654455A (en) | Laser gas analyzer for multicomponent multiplexing measurement | |
| CN102252982A (en) | Wavelength drift compensation method for laser gas analyzer | |
| CN101738382A (en) | Transformer failure gas monitoring system and method | |
| CN105067564B (en) | A kind of optical fiber gas concentration detection method with temperature compensation capability | |
| CN104903703A (en) | Gas absorption spectroscopy device and gas absorption spectroscopy method | |
| CN104280362A (en) | Online high-temperature water vapor laser spectrum detection system | |
| CN204556499U (en) | The multi-channel high-speed data acquisition and processing system of tuning diode absorption spectrum | |
| CN203658243U (en) | C2H2 and CH4 detection device based on photoacoustic spectrometry | |
| CN104764719A (en) | Absorption peak locking mode-based device for measuring components of internal combustion engine exhaust gas | |
| KR101923003B1 (en) | Method for determining the concentration of a gas component and spectrometer therefor | |
| CN107850533A (en) | Concentration measurement apparatus | |
| CN103499545A (en) | Semiconductor laser gas detection system with function of gas reference cavity feedback compensation | |
| CN102062722B (en) | Laser program-controlled gas concentration detection system and detection method | |
| CN103528993A (en) | Laser gas analyzer | |
| CN102121902A (en) | Online Raman spectrometer correction device and correction method thereof | |
| CN105136740A (en) | Temperature and humidify monitoring system based on TDLAS | |
| CN102654456A (en) | Device and method for multiple-parameter measurement of combustion state of coal-fired boiler | |
| JP5630642B2 (en) | Laser gas analyzer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C12 | Rejection of a patent application after its publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20140219 |