CN109855923A - A kind of multiple spot approximation extraction-type the escaping of ammonia detection method in situ based on overlength light path - Google Patents
A kind of multiple spot approximation extraction-type the escaping of ammonia detection method in situ based on overlength light path Download PDFInfo
- Publication number
- CN109855923A CN109855923A CN201910141688.8A CN201910141688A CN109855923A CN 109855923 A CN109855923 A CN 109855923A CN 201910141688 A CN201910141688 A CN 201910141688A CN 109855923 A CN109855923 A CN 109855923A
- Authority
- CN
- China
- Prior art keywords
- detection
- signal
- host
- flue
- ammonia
- 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.)
- Withdrawn
Links
Abstract
The approximate extraction-type the escaping of ammonia detection method in situ of the multiple spot based on overlength light path that the invention discloses a kind of, the following steps are included: S1: host is mounted on the analysis room CEMS, it will test unit to be mounted on denitration flue, then host and detection unit are powered on, host and detection unit pass through optical fiber and coaxial cable progress information connection；S2: heat tracing is carried out to gas detection cell by temperature control system.The present invention can be by arranging that multiple TDLAS detection units form the approximate extraction-type the escaping of ammonia on-line monitoring system in situ of multiple spot of one or more sets overlength light paths, the ammonia slip concentration real-time online of multiple positions detects, really reflect the actual concentration distribution of escape ammonia in denitration rear pass, and measured value is transferred to SCR control system, CEMS system and Power Plant DCS System, the ammonia spraying amount of SCR is optimized.
Description
Technical field
The present invention relates to denitration technology optimization control field more particularly to a kind of multiple spot based on overlength light path are approximate in situ
Extraction-type the escaping of ammonia detection method.
Background technique
For coal-burning power plant, there is part NH in SCR technique3As flue gas escapes out catalyst layer.The escaping of ammonia is maximum
Harm is the SO in escape ammonia and flue gas3Reaction generates NH4HSO4, abbreviation ABS, ABS be in a liquid state in certain temperature section,
And there are adhesive characteristics, and the air preheater after SCR is by chance in this temperature range, the ABS of liquid is attached to the table of air preheater
Face, and the dust in flue gas is adsorbed, it causes the front and back pressure difference of air preheater to increase, causes air preheater to block when serious, endanger boiler
Operational safety, power plant must blowing out clean air preheater, therefore cause very huge economic loss.Therefore, real-time detection escape ammonia
Concentration plays a crucial role the SCR optimal control of coal-burning power plant.
Use the methods of chemical analysis method, differential absorption spectroscopy, fourier transform infrared spectroscopy both at home and abroad at present
Detect escape ammonia concentration, for these methods there are laser individual reflection, light path is short, laser cannot penetrate high concentrate dust flue gas with
And various problem such as single-point detection, it is unable to the concentration that real-time online accurately detects escape ammonia, for this purpose, we have proposed one
The approximate extraction-type the escaping of ammonia detection method in situ of multiple spot of the kind based on overlength light path.
Summary of the invention
The purpose of the present invention is to solve disadvantage existing in the prior art, and propose a kind of based on overlength light path
The approximate extraction-type the escaping of ammonia detection method in situ of multiple spot.
To achieve the goals above, present invention employs following technical solutions:
A kind of multiple spot approximation extraction-type the escaping of ammonia detection method in situ based on overlength light path, comprising the following steps:
S1: host is mounted on the analysis room CEMS, unit is will test and is mounted on denitration flue, then by host and detection
Unit is powered on, and host and detection unit pass through optical fiber and coaxial cable progress information connection；
S2: heat tracing is carried out to gas detection cell by temperature control system；
S3: and then instrument compressed air is connected, the jet pump in detection unit is started to work, and is formed in detection unit
One is significantly less than the strong negative-pressure environment of pressure in flue, is similar to install one or more low pressure force environments in flue outer wall
Gas bypass, flue gas flow and flow velocity in detection unit can adjust by jet pump；
S4: and then flow through the partial fume inside flue by smoke sampling bar and be significantly less than the detection list of flue pressure
Member；
S5: flue gas passes through the ultra-fine filter in detection unit first, and filtered clean flue gas enters detection pond body,
Carry out the detection of overlength light path laser；
S6: the frequency laser that host issues passes through in optical fiber synchronous driving to the detection cell body of multiple detection units；
S7: laser is finally received by photoelectric sensor after passing through detection pond body and multiple reflections formation overlength light path；
S8: the electric signal with NH3 concentration information in detection pond body is sent to host by coaxial cable and passes through analysis
Method is handled；
S9: host obtains NH3 concentration signal, and is converted into analog signal and sends SCR control system, CEMS system and electricity to
Factory's DCS system；
S10: the flue gas after analysis empty or is discharged into flue by pipe special to complete to detect.
The analysis method the following steps are included:
The laser that D1: one beam intensity is I0 transmitted through light intensity attenuation after uniform under test gas medium be It, the degree of decaying
τvFollow Beer-Lambert law:
Wherein, S (cm-2·atm-1) it is characterized the strong v of Absorption Line (cm-1) of the spectral line wave number inswept for laser in time domain
Range, it be gas medium pressure x is that gas volume is dense that T (K) can be obtained by etalon measurement, which is gas medium temperature P (atm),
Spending L (cm) is optical path lengthFor linear function, since under high-temperature pressure, collision broadening is suitable with dopplerbroadening, makes
It is described with Voigt linear function, wherein the line parameters in linear function are provided by HITRAN12 database；
D2: the transmitted light intensity of emulation can state are as follows:
Wherein,To test the background light intensity signal measured,For emulation absorption light intensity signal (text on
Mark M, S are respectively used to distinguish experiment and emulation signal)；
D3: willBy digital servo-control filter, each harmonic signal component is extracted:
Wherein,The nth harmonic X and Y-direction component of absorption signal are respectively emulated,For the absolute value of harmonic signal；
D4: background signal can be obtained in the same mannerN timesHarmonic waveAnd its X and Y-direction componentWithThe normalized nth harmonic signal of button background 1f that emulation obtains in this way can indicate are as follows:
Wherein, remember that the transmitted light intensity signal measured isBy identical digital servo-control filter, by same place
The button background 1f of the available measurement of reason mode normalizes nth harmonic signal
Preferably, the temperature control system is no more than 300 degrees Celsius to gas detection cell heating temperature.
The invention has the benefit that
1: can connect multiple TDLAS terminal composition multiple spot extraction-type the escaping of ammonia monitoring systems, the escaping of ammonia of multiple positions
Concentration real-time detection, the concentration distribution of escape ammonia is really reflected, and measured value is transferred to power plant, to the ammonia spraying amount of SCR
It optimizes.
2: the escaping of ammonia detection unit of system is directly installed on flue, and sample gas is directly entered filtering by feeler lever
Chamber, filtered gas are directly entered multiple reflections detection cell, and the gas that detection cell comes out is returned directly to flue or emptying, keeps away
The escape ammonia loss on traditional sampling pipeline is exempted from.
3: the multiple reflecting pool light path of system is not fixed and invariable, can be according to the requirement at scene in 10-30 meters of models
Interior adjusting is enclosed, since light path improves 10-20 times relative to correlation optical side, the escaping of ammonia detection sensitivity also improves 10-
20 times, sensitivity reaches 0.1ppm.
4: system uses non-calibrating technology, and standard gas company cannot substantially provide 10ppm accurate ammonia Standard Gases below
Body, traditional calibration technique are difficult to carry out on-line correction.
5: the modified algorithm of intersection based on TDLAS is utilized, is there is H2O、CO2Essence is remained in the case where equal gases interference
The really concentration of measurement escape ammonia.
Specific embodiment
The technical scheme in the embodiments of the invention will be clearly and completely described below, it is clear that described implementation
Example is only a part of the embodiment of the present invention, instead of all the embodiments.
A kind of multiple spot approximation extraction-type the escaping of ammonia detection method in situ based on overlength light path, comprising the following steps:
S1: host is mounted on the analysis room CEMS, unit is will test and is mounted on denitration flue, then by host and detection
Unit is powered on, and host and detection unit pass through optical fiber and coaxial cable progress information connection；
S2: heat tracing is carried out to gas detection cell by temperature control system；
S3: and then instrument compressed air is connected, the jet pump in detection unit is started to work, and is formed in detection unit
One is significantly less than the strong negative-pressure environment of pressure in flue, is similar to install one or more low pressure force environments in flue outer wall
Gas bypass, flue gas flow and flow velocity in detection unit can adjust by jet pump；
S4: and then flow through the partial fume inside flue by smoke sampling bar and be significantly less than the detection list of flue pressure
Member；
S5: flue gas passes through the ultra-fine filter in detection unit first, and filtered clean flue gas enters detection pond body,
Carry out the detection of overlength light path laser；
S6: the frequency laser that host issues passes through in optical fiber synchronous driving to the detection cell body of multiple detection units；
S7: laser is finally received by photoelectric sensor after passing through detection pond body and multiple reflections formation overlength light path；
S8: the electric signal with NH3 concentration information in detection pond body is sent to host by coaxial cable and passes through analysis
Method is handled；
S9: host obtains NH3 concentration signal, and is converted into analog signal and sends SCR control system, CEMS system and electricity to
Factory's DCS system；
S10: the flue gas after analysis empty or is discharged into flue by pipe special to complete to detect.
Analysis method the following steps are included:
The laser that D1: one beam intensity is I0 transmitted through light intensity attenuation after uniform under test gas medium be It, the degree of decaying
τvFollow Beer-Lambert law:
Wherein, S (cm-2·atm-1) it is characterized the strong v of Absorption Line (cm-1) of the spectral line wave number inswept for laser in time domain
Range, it be gas medium pressure x is that gas volume is dense that T (K) can be obtained by etalon measurement, which is gas medium temperature P (atm),
Spending L (cm) is optical path lengthFor linear function, since under high-temperature pressure, collision broadening is suitable with dopplerbroadening, makes
It is described with Voigt linear function, wherein the line parameters in linear function are provided by HITRAN12 database；
D2: the transmitted light intensity of emulation can state are as follows:
Wherein,To test the background light intensity signal measured,For emulation absorption light intensity signal (text on
Mark M, S are respectively used to distinguish experiment and emulation signal)；
D3: willBy digital servo-control filter, each harmonic signal component is extracted:
Wherein,The nth harmonic X and Y-direction component of absorption signal are respectively emulated,For the absolute value of harmonic signal；
D4: background signal can be obtained in the same mannerN timesHarmonic waveAnd its X and Y-direction componentWithThe normalized nth harmonic signal of button background 1f that emulation obtains in this way can indicate are as follows:
Wherein, remember that the transmitted light intensity signal measured isBy identical digital servo-control filter, by same place
The button background 1f of the available measurement of reason mode normalizes nth harmonic signalTemperature control system is to gas detection cell
Heating temperature is no more than 300 degrees Celsius.
Following table is that the prior art detects contrast table:
The foregoing is only a preferred embodiment of the present invention, but scope of protection of the present invention is not limited thereto,
Anyone skilled in the art in the technical scope disclosed by the present invention, according to the technique and scheme of the present invention and its
Inventive concept is subject to equivalent substitution or change, should be covered by the protection scope of the present invention.
Claims (3)
1. a kind of multiple spot approximation extraction-type the escaping of ammonia detection method in situ based on overlength light path, which is characterized in that including following
Step:
S1: host is mounted on the analysis room CEMS, unit is will test and is mounted on denitration flue, then by host and detection unit
Powered on, host and detection unit pass through optical fiber and coaxial cable progress information connection；
S2: heat tracing is carried out to gas detection cell by temperature control system；
S3: and then instrument compressed air is connected, the jet pump in detection unit is started to work, and one is formed in detection unit
It is significantly less than the strong negative-pressure environment of pressure in flue, is similar to that the cigarette of one or more low pressure force environments is installed in flue outer wall
Gas bypass, can adjust flue gas flow and flow velocity in detection unit by jet pump；
S4: and then flow through the partial fume inside flue by smoke sampling bar and be significantly less than the detection unit of flue pressure；
S5: flue gas passes through the ultra-fine filter in detection unit first, and filtered clean flue gas enters detection pond body, carries out
The detection of overlength light path laser；
S6: the frequency laser that host issues passes through in optical fiber synchronous driving to the detection cell body of multiple detection units；
S7: laser is finally received by photoelectric sensor after passing through detection pond body and multiple reflections formation overlength light path；
S8: the electric signal with NH3 concentration information in detection pond body is sent to host by coaxial cable and passes through analysis method
It is handled；
S9: host obtains NH3 concentration signal, and is converted into analog signal and sends SCR control system, CEMS system and power plant to
DCS system；
S10: the flue gas after analysis empty or is discharged into flue by pipe special to complete to detect.
2. a kind of multiple spot approximation extraction-type the escaping of ammonia detection method in situ based on overlength light path according to claim 1,
It is characterized in that, the analysis method the following steps are included:
The laser that D1: one beam intensity is I0 transmitted through light intensity attenuation after uniform under test gas medium be It, the degree τ of decayingvIt follows
Beer-Lambert law:
Wherein, S (cm-2·atm-1) it is characterized the strong v of Absorption Line (cm-1) of the spectral line wave-number range inswept for laser in time domain,
It is gas medium pressure x is void fraction L that T (K) can be obtained by etalon measurement, which is gas medium temperature P (atm),
It (cm) is optical path lengthIt is used for linear function since under high-temperature pressure, collision broadening is suitable with dopplerbroadening
Voigt linear function describes, and wherein the line parameters in linear function are provided by HITRAN12 database；
D2: the transmitted light intensity of emulation can state are as follows:
Wherein,To test the background light intensity signal measured,For emulation absorption light intensity signal (text in subscript M, S
It is respectively used to distinguish experiment and emulation signal)；
D3: willBy digital servo-control filter, each harmonic signal component is extracted:
Wherein,The nth harmonic X and Y-direction component of absorption signal are respectively emulated,For the absolute value of harmonic signal；
D4: background signal can be obtained in the same mannerN timesHarmonic waveAnd its X and Y-direction componentWithThis
What sample emulated, which buckles the normalized nth harmonic signal of background 1f, to indicate are as follows:
Wherein, remember that the transmitted light intensity signal measured isBy identical digital servo-control filter, by same processing side
The button background 1f of the available measurement of formula normalizes nth harmonic signal
3. a kind of multiple spot approximation extraction-type the escaping of ammonia detection method in situ based on overlength light path according to claim 1,
It is characterized in that, the temperature control system is no more than 300 degrees Celsius to gas detection cell heating temperature.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910141688.8A CN109855923A (en) | 2019-02-26 | 2019-02-26 | A kind of multiple spot approximation extraction-type the escaping of ammonia detection method in situ based on overlength light path |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910141688.8A CN109855923A (en) | 2019-02-26 | 2019-02-26 | A kind of multiple spot approximation extraction-type the escaping of ammonia detection method in situ based on overlength light path |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109855923A true CN109855923A (en) | 2019-06-07 |
Family
ID=66898874
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910141688.8A Withdrawn CN109855923A (en) | 2019-02-26 | 2019-02-26 | A kind of multiple spot approximation extraction-type the escaping of ammonia detection method in situ based on overlength light path |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109855923A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110907395A (en) * | 2019-12-02 | 2020-03-24 | 光钙(上海)高科技有限公司 | Direct absorption type TDLAS gas analyzer and method |
-
2019
- 2019-02-26 CN CN201910141688.8A patent/CN109855923A/en not_active Withdrawn
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110907395A (en) * | 2019-12-02 | 2020-03-24 | 光钙(上海)高科技有限公司 | Direct absorption type TDLAS gas analyzer and method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1908623B (en) | Multi-component infrared online gas analyzer | |
| CN109655227B (en) | Low-enthalpy arc heater airflow enthalpy value diagnosis system and diagnosis method | |
| CN101506646B (en) | Gas analyzing device and gas analyzing method | |
| CN107741386B (en) | Pipeline particle on-line detection device and method | |
| CN106248442B (en) | SO in a kind of detection flue gas3Method | |
| CN103620377A (en) | Device with a measurement arrangement for optical measurement of gases and gas mixtures, with compensation of environmental influences | |
| CN104458635B (en) | Aircraft fire alarm detection device and method based on CO2 gas concentration monitoring | |
| CN111289645A (en) | Fixed pollution source volatile organic compound on-line monitoring system | |
| CN204287038U (en) | A kind of based on CO 2the aircraft fire detection device of gas concentration inspect | |
| CN107271365A (en) | A kind of device of on-line determination the escaping of ammonia in situ | |
| CN109855923A (en) | A kind of multiple spot approximation extraction-type the escaping of ammonia detection method in situ based on overlength light path | |
| EP2847576A2 (en) | Extractive continuous ammonia monitoring system | |
| CN113267392A (en) | Ship exhaust emission monitoring system and control method thereof | |
| CN108801718A (en) | A kind of tail gas on-line monitoring system peculiar to vessel | |
| CN106076115A (en) | The flow field detecting system of SCR denitration technique | |
| CN106289884B (en) | A kind of SO3The method of on-line checking | |
| CN106644999A (en) | Dual-gas-cell carbon monoxide concentration real-time detection device for coal mill | |
| CN111157477A (en) | Total hydrocarbon concentration detector and total hydrocarbon concentration detection method | |
| CN106500951B (en) | Measure measuring probe, measuring system and the method for hypersonic flow parameter | |
| CN210923465U (en) | Carbon dioxide on-line monitoring system of coal-fired power plant | |
| CN105203471A (en) | Novel flue gas tester | |
| CN216792012U (en) | Two-channel multi-component smoke emission online monitoring system | |
| CN205679585U (en) | The flow field detecting system of SCR denitration technique | |
| JPS6182142A (en) | Measuring device for concentration of gas in gas current | |
| Dittmann et al. | Multiple wavelength extinction technique for particle characterization in dense particle clouds |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WW01 | Invention patent application withdrawn after publication |
Application publication date: 20190607 |
|
| WW01 | Invention patent application withdrawn after publication |