Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 1 EMISSION MEASURMENT II. GAS ANALYZERS Viktória Barbara KOVÁCS
Jan 17, 2016
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 1
EMISSION MEASURMENT II.GAS ANALYZERS
Viktória Barbara KOVÁCS
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 2
EMISSION MEASUREMENT
Harmful components Emission measuring systems
– In-situ: (in-stack, cross-stack) measurement– Ex-situ: extractive measurement: „analyzers with a
measuring probe” Requirements of analyzers Reference methods: Analyzers at D.E.E
– NDIR (CO, CO2, CH4, ….) Servomex 1400B4 SPX O2/CO2
Thermo 48C CO
– (H)CLD (NO, NOx,) Thermo 42C NO-NO2-NOx
– FID (THC, CxHy, VOC) Bernath Atomic Modell 9900 THC
– PMD (O2) Servomex 1400B4 SPX O2/CO2
Measuring Cell Chromatography Older techniques
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 3
HARMFUL COMPONENTS OF FLUE GAS CO2: GHG CO: poisonous (suffocating from ~700ppm) THC (VOC, PAH)
– depends on molecule: – Methane: GHG, but PAH carcinogenic, etc.
NOx: acid rain SOx: acid rain (Dioxin, furans: teratogenic, mutagenic)
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 4
IN-SITU MEASUREMENT
NOx reduction with SCR_SICK.mp4:https://www.youtube.com/watch?v=pxiRC44tN70
Optic grid
UV detector
UV transmitter lamp
Condenser lens
mirror lens
windowMeasuring
section
Triple reflector
mirror
Beam splitting mirror
Evaluation unit Measuring unit
Advantages– Direct and immediate measurement in
process– Non-contact measurement: suitable for
aggressive or corrosive gases– Very short response time– Very low maintenance requirements
Disadvantages– More expensive– Simultaneously measurement of more
component is critical– Humidity causes problems
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 5
EX-SITU MEASURMENT
Advantages– For applications with high dust concentration– Measurement is possible far from the emission source– More components can be measured simultaneously– Low concentration is measurable– Suitable for difficult measurement tasks
Disadvantages– More units– High response time– Corrosion risks– Condensation risk– Soot deposit („pipe remembers”)
P
E le m z õ kM in ta e lõ k é sz ítõ
h ű tőM in ta
K a lib rá ló g á z o k
F ű tö tt m in ta v e v ő
Analyzers
Standard gases
heated pipe
Sample
Sample conditioning
system
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 6
REQUIREMENTS OF ANALYZERS
1. Physical working principle2. Fast (reaction time under sec.)3. Stable in time4. High sensitivity5. High selectivity6. Low inter-sensitivity7. Linear characteristic8. Independent from ambient condition9. Protected from ambient 10. Cheap
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 7
IR SPECTROSCOPY
deals with the infrared region of the electromagnetic spectrum
it can be used to identify and study chemicals molecules absorb specific frequencies that are
characteristic of their structure the frequency of the absorbed radiation matches the
transition energy of the bond or group that vibrates passing a beam of IR light through the sample: when
the frequency of the IR is the same as the vibrational frequency of a bond, absorption occurs
λ: 780 nm –1000 μm (f: 300 GHz – 384 THz) IR_1.avi:https://www.youtube.com/watch?v=DDTIJgIh86E
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 8
VIBRATION OF CH2 IN A CH2X2 GROUP
Symmetricalstretching
Antisymmetricalstretching Scissoring
Rocking Wagging Twisting
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 9
NDIR (NON-DISPERSIVE INFRARED ABSORPTION)
http://www.tsi.com/iaq/appnote/ndir_co2.shtmlNDIR.avi:https://www.youtube.com/watch?v=a2dEYmW0xys
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 10
NDIR (NON-DISPERSIVE INFRARED ABSORPTION)
http://www.signalinstruments.com
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 11
NDIR (NON-DISPERSIVE INFRARED ABSORPTION)
http://www.signalinstruments.com
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 12
NDIR (NON-DISPERSIVE INFRARED ABSORPTION)IR SPECTRUM
http://www.mdpi.com/1424-8220/13/6/7079/htm
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 13
NDIR – CO2
IR_3.avi:https://www.youtube.com/watch?v=FR9DFkenWUU
http://www.raesystems.com
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 14
FTIR - FURIER TRANSFORMED IR SPECTROSCOPY measurement technique that allows one to record
IR spectra Infrared light is guided through an interferometer
and then through the sample (or vice versa). A moving mirror inside the apparatus alters the
distribution of infrared light that passes through the interferometer.
The signal directly recorded, called an "interferogram", represents light output as a function of mirror position.
A data-processing technique called Fourier transform turns this raw data into the desired result (the sample's spectrum): Light output as a function of infrared wavelength (or equivalently, wavenumber).
The sample's spectrum is always compared to a reference.
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 15
NDIR/ FTIR COMPARISONGas Filter Correlation IR Narrow frequency range defined
by the filter One filter for one component More component more filter More filters more calibrations
Fourier Transform Infrared (FTIR)• "Fellgett's advantage" or the "multiplex advantage„
– information at all frequencies is collected simultaneously– improving both speed and signal-to-noise ratio
• "Jacquinot's Throughput Advantage„ - higher light levels • Better wavelength accuracy• Lower stray light sensitivity• More components are observable simultaneously
IR_2.avihttps://www.youtube.com/watch?v=DDTIJgIh86E
Kertész Károly: Folyamatos gázelemzés
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 16
THERMO 48C CO ANALYZER (D.E.E.) GFC IR
http://www.ierents.com/Spec%20Pages/Thermo%2048C%20CO.pdf
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 17
CHEMILUMINESCENCE
Nitric oxide (NO) and ozone (O3) react to produce a characteristic luminescence with an intensity linearly proportional to the NO concentration.
NO+O3 → (1-n)·NO2+ n·NO2*+O2
IR light emission results when excited NO2 molecules decay to lower energy states.
NO2* → NO2+ hv Nitrogen dioxide (NO2) must be first
transformed into NO before it can be measured with chemiluminescent method.
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 18
CLD (CHEMILUMINESCENT DETECTOR)
Principle: NO+O3→NO2*+O2
www.emersonprocess.comChemiluminescence magic.mp4:https://www.youtube.com/watch?v=8_82cNtZSQE
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 19
THERMO 42C NO-NO2-NOX ANALYZER (D.E.E.)CLD
Converter - efficiency depends on temperature: molybdenum heated to approximately
325°C- consists of an insulated housing, heater, replaceable cartridge, and a type K
thermocouple
NO+O3→NO2*+O2 http://www.thermo.com.cn/Resources/200802/productPDF_20998.pdf
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 20
FID - FLAME IONISATION DETECTOR
In a flame, oxygen and hydrogen are burned.
When in a hydrogen flame other molecules pass, these will burn also and increase the amount of ions.
The ions generated by the flame are attracted to the positive side of an electrical field in the detector cell.
The electrical current in the detector cell changes, this change is measured and has a direct correlation with the concentration.
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 21
FID- FLAME IONISATION DETECTORCH + O CHO+ +
e-
- Measurable current : 10-12A - Without sample: 10-14A - Detector response~ measurable
*107
- Sensitivity 10-2 compared to TCDFid.swfhttp://www.chromedia.org/dchro/swf/ZsxnjdeIW.swf
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 22
FID - FLAME IONIZATION DETECTOR
CH + O CHO+ + e-
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 23
PMD (PARAMAGNETIC DETECTOR) Oxygen is attracted into a strong magnetic field. Most other
gases are not. A focused magnetic field is created. Any oxygen that is
present will be attracted into the strongest part of the magnetic field.
Two nitrogen filled glass spheres are mounted on a rotating suspension within a magnetic field.
A mirror is mounted centrally on the suspension. Light is shone onto the mirror. The reflected light is directed onto a pair of photocells. Oxygen attracted into the magnetic field will displace the nitrogen filled spheres, causing the suspension to rotate. The photocells will detect the movement and generate a signal.
The signal generated by the photocells is passed to a feedback system. The feedback system will pass a current around a wire mounted on the suspension. This causes a motor effect, which will keep the suspension in its original position. The current measured flowing around the wire will be directly proportional to the concentration of oxygen within the gas mixture.
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 24
PMD (PARAMAGNETIC DETECTOR)
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 25
PMD (PARAMAGNETIC DETECTOR)
www.fic-net.co.jp
O2 +100 Nitrogen -0.42
Air +21 (száraz)
Chlorine -0.13
CO2 -0.61 Hydrogen -0.12
Argon -0.58 Acetylene
-0.38
Ammonia
-0.58 N2O -0.58
Ethane -0.83 NO +43.8
Methane -0.37 NO2 +28.0
Cross contamination
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 26
ALTERNATIVE O2 MEASUREMENT:ELECTROCHEMICAL METHOD
Oxygen Sensor.avi:https://www.youtube.com/watch?v=Fl3aD1qJrEg&list=UUycARi6zsqrcC0M90gdve5A
1- air; 2- exhaust gas; 3- sensor; 4- electrolyte (zirconium dioxide);
5- exhaust side; 6-reference side; 7- span
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 27
MEASURING CELL TESTO 350
CO SO2 NO NO2 H2S
CO 100 65 30 -60 340
SO2 2 100 0 -100
200
NO 0 5 100 15 18
NO2 -1 -5 5 100 20
H2S 7 20 0 -20 100
Cross contamination
I
D iffu z ió s g á tM érő e lek tró d (an ó d )
E lek tro lit
D iffu z ió s g á tM érő e lek tró d (k a tó d )
M in ta
2 H +
2 e -
2 e -
C O 2
1 /2 O 2
C O
R efe re n c ia g á z
sample gas
reference gas
diffusion barrier
diffusion barrier
electrolyte
Probe (anode)
Probe (cathode)
–SO2 activated carbon, gold
- CO, platinum
–platinum
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 28
GAS CHROMATOGRAPHY
GC Columns.avi:https://www.youtube.com/watch?v=q0pM-k0SvOQ
http://web.mit.edu/12.000/www/finalpresentation/experiments/gcms.html
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 29
CHROMATOGRAM
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 30
QUESTIONS
What are the harmful components of exhaust gas? Why are they harmful?
Describe cross-stack measuring technique! (advantages, disadvantages)
Describe extractive measuring technique! (advantages, disadvantages)
What are the requirements of analyzers? Describe NDIR! (working principle, detected
components) Describe CLD! (working principle, detected
components) Describe FID! (working principle, detected
components) Describe PMD! (working principle, detected
components)
Viktória B. Kovács| Pollutant formation | © 2015 BMEGEENAG51 | D218 | 2015-16-1 | 31
THANK YOU FOR YOUR ATTENTION!
Viktória Barbara KOVÁCS
Build. D room 207B06 1 463 2592