instrumentation for marine black carbon measurements september... · instrumentation for marine...
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INSTRUMENTATION FOR MARINE BLACK CARBON MEASUREMENTS
Workshop on Marine Black Carbon Emissions, Ottawa, 9-10th of September 2014
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Outline IMO Measurement Methods and Definitions for Black Carbon
Selectivity of Different Instruments
AVL Instruments to Measure the Mass of Light-absorbing
Particles from Marine Engines AVL 415 Smoke Meter AVL 483 Micro Soot Sensor (MSS) Correlation Filter Smoke Meter 415SE - MSS Correlation Filter Smoke Meter 415SE - MAAP
Conclusions
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Measurement Methods for BC
Equivalent Black Carbon (eBC): Light-Absorbing Carbon (LAC)
Filter Smoke Number (FSN) Filter Smoke Number (FSN)
Multi Angle Absorption Photometry (MAAP)
Photo-Acoustic Spectroscopy (PAS)
Laser Induced Incandescence (LII)
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The MEPC technical committee should decide a definition for BC as being either equivalent Black Carbon (eBC) or Light-absorbing Carbon (LAC)1.
The following methods were selected as appropriate for the proposed definitions:
1According to PPR1/WP.5 dated 6th of February 2014.
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Selectivity of Different Instruments
1Filter Smoke Number is a standardized method conform IS0 10054 2Opacity is a standardized method conform IS0 11614
H2O(vap)
Abrasion/Ash
SO4-
Hydrocarbons
Carbon/Soot
NO2
NO
Filte
r Gra
vim
etry
Filte
r Sm
oke
Num
ber1
PA
S
Opa
city
2
LII
MA
AP
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AVL Instruments to Measure the Mass of Light-absorbing Particles
from Marine Engines
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AVL 415SE Measurement Principle Measures the reflection of visible light from a soot loaded filter surface.
The instrument samples a user defined volume of exhaust gas and draws it through a clean filter paper.
The filtered “soot” causes blackening of the filter paper which is detected by an optical measuring head.
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Sample volume – Dead volume – Leak volume Filter area
Effective length =
Sam
ple
volu
me
Dead volume
Effe
ctiv
e le
ngth
RF RS
Lightsource
Reflectometer
Detector
Clean filter Blackened filter
Reflectometer
Detector Lightsource
RF RS
Lightsource
Reflectometer
Detector
Clean filter Blackened filter
Reflectometer
Detector Lightsource
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AVL 415SE – Filter Smoke Meter Is a well known established measurement method
used for engine development and for production conformity tests (Is a standard emission equipment on each new engine test bed).
Standardized method conform IS0 10054
Filter Smoke Meter could be also installed on ships.
Integral measurements of transient peaks with preselected sampling time for BC estimates on ship manoeuvers.
High sensitivity through variable sampling volume. (can be parameterized from 2 seconds up to 2 minutes) • Current Resolution: 0.001FSN or 0.01 mg/m3
• Detection Limit: 0.002FSN or ~ 20 µg/m3
Robust instrument (against heavy fuel).
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AVL 483 Micro Soot Sensor (MSS) Measurement Principle
Sample diluted exhaust (CVS, SPC, or Conditioning Unit)
Exhaust gas will be directed through a measuring chamber and thermally animated by a modulated laser beam
Modulated IR-Light
Modulated heating produces periodic pressure pulsation,
which will be detected by a microphone as acoustic wave
Modulated Absorption
Modulated Expansion
Sound Wave
Acoustic detection by microphone
Signal will be amplified in a pre-amplifier and filtered in a
„Lock-In“- amplifier.
Lock-In Recording
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AVL 483 Micro Soot Sensor (MSS)
The instrument is based on the photoacoustic measurement method
Time resolved signal (Digital data rate up to 10Hz, rise time <1sec)
High sensitivity (5 µg/m³)
High dynamic range: mg/m3 to g/m3 (up to 1 g/m3 with dilution)
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Micro Soot Sensor and Smoke Meter
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Instrument Measurement Value
Principle Detected Components
Micro Soot Sensor (MSS)
mg/m3
Light absorption based on photo-acoustic method
Measures the 808 nm light absorbed by the particles. Carbon Soot “C” (“eBC”), “Black Smoke”
Smoke Meter (SM)
FSN and mg/m3 Light absorption based on reflection method
Measures the reflection of visible light (absorbing eye response according CIE 69) from a soot loaded filter surface. Carbon soot “C” (“eBC”), “Black Smoke”
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Measurements with 415 SE Smoke Meter are Reliable and Comparable with Data From Other Sources eBC (equivalent Black Carbon) concentration derived from AVL filter smoke
measurements correlates very well to the values given by PAS (Photo Acoustic Soot Sensor) and the ~ 1h average values of MAAP (Multi Angle Absorption Photometer).
Location and design of the sampling probe is essential in order to obtain consistent test results.
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y = 1.005xR² = 0.9933
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50
60
70
80
90
0 10 20 30 40 50 60 70 80 90
PAS
[mg/
m3 ]
Filter Smoke Meter [mg/m3]
Correlation Smoke Meter 415SE - PAS
LD Diesel Engine No after-treatment Standard Diesel Fuel with S < 10 ppm
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Correlation 415SE - MAAP
Data Source: ACTRIS Workshop Feb, 2013 at Leibniz Institute for Tropospheric Research (TROPOS)
not published yet
the Smoke Meter and MAAP data was post-processed using Excel least square averaging
improved Smoke Meter for low detection limits (not released yet)
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Conclusions
Filter Smoke Meter measures the reflection of visible light from a soot loaded surface.
AVL Filter Smoke Meter correlates well to eBC only (not total PM).
The AVL Filter Smoke Meter shows good correlation to PAS and MAAP.
For on-board marine applications specific adaptions may be required.
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Thank You For Your Attention!