Copyright © SRC 2013 Copyright © SRC 2013 1 An Introduction to Stack Sampling Air and Climate Business Unit Environment Division
Copyright © SRC 2013 Copyright © SRC 2013 1
An Introduction to Stack Sampling
Air and Climate Business Unit Environment Division
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Safety and Stack Sampling
Anthropogenic and Natural Sources of Air Pollution
Secondary Air Pollution
Particulate and Gaseous Pollutants
Industrial (Stationary) Source Testing (how, why, when,where)
Future Direction of Source Testing
SUMMARY
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Safety is an over-riding consideration
at SRC
Many safety factors come into play when conducting stack sampling – safety regulations at each site - orientation site specific safety items.
SRC conducts a tailgate meeting prior to the start of each day while stack sampling.
Safety Aspects of Stack Sampling
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Fall arrest, tie off points, working on roofs, scaffold or permanent platforms around the stack. Platform safety – ladder safety, hoisting considerations.
Weather conditions of wind, rain, snow are considered.
Safety Aspects of Stack Sampling
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Pollutant Emission Sources
www.nature.nps.gov
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Secondary Air Pollutants
nptel.ac.in
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Health and Air Pollution
healthtipsinsurance.com
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Size of airborne particulate expressed as aerodynamic diameter (ad)(µm).
Unit density 1 gm/cm³, spherical.
Terminal velocity of particulate in the atmosphere is dependent on size.
Ranges from 0.1 - 30 cm/sec for unit density spherical particulate with ad of 1 – 100 µm respectively.
Particulate Pollutants
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Particulate Size and Deposition In Humans
www.enve-lab.eu/wp-content/uploads/2013/.jpg
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Particulate Suspension in the Environment
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2.5 µm particle (50% suspended) after 10 hr travels 100 km in 10 km/hr wind.
10 µm particle (50% suspended) after 10 hr travels 6.5 km in 10 km/hr wind.
100 µm particle (50% suspended) after 10 hr travels 0.1 km in 10 km/hr wind.
Particulate Suspension Time
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Determine concentration (mg/drm³), emission rate (kg/h) and/or intensity (gm/tonne) or (gm/GJ of NOx energy production) from a stationary source.
If the production rate and process stream are constant and the air pollution control devices are operating correctly, the emission rate of pollutants should be constant.
Annual stack testing at an Industrial site should give representative results year over year.
Why Perform Stack Sampling
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Stack Sampling Train for Particulate
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Method 5 Sampling Train
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The General Stack Sampling Train
Probe, nozzle, pitot tubes, thermocouples
Hot box houses the filter
Cold box houses the impingers (various liquids)
Umbilical cord attaches the sampling train to the control console
Control console and operator
Isokinetic Sampling (particulate)
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The Control Console
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Sample Nozzle
Sharp tapered edge important for sampling
Nozzles come in a variety of materials for different heat conditions within the stack
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Isokinetic Sampling Considerations
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Heat Limits for Various Materials
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Environment Canada’s Reference Methods for Source Testing: Measurement of Releases of Particulate from Stationary Sources RM EPS 1/RM/8 December 1993
U.S. Code of Federal Regulations Protection of the Environment 40 Part 60 outlines Methods 1 to 320 which deal with all types of sampling protocols for particulate, gases, radionuclides and other pollutants.
Stack Sampling Methodology
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Requirements on a Circular Stack
Alberta Stack Sampling Code
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Number of sample points on traverse
Environment Canada
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Prescribed Sampling Points
Environment Canada
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Particulate Sizing Devices
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Sizing of Particulate
SEM image of particulate after the cyclone before the scrubber
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Techniques for Sizing Particulate
Pollution Control Systems Corp.
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Combustion Processes and Stack Testing
Perry’s Chemical Engineers’ Handbook Seventh Ed.
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Wet chemical techniques for SO2, NOx, HCl, NH3, Cl2 involves absorption into appropriate solution.
Instrumental gas analyzers using electrochemical sensing technology - need to remove water from the stack prior to detection.
Fourier Transform Infrared (FTIR) analysis of stack gases (not for H2, Cl2, O2, N2 etc.)
Gaseous Sampling Methods
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US EPA Method 8 for SO₂ and H2SO4
US EPA Method 8
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US EPA Method 7 for NOx
US EPA Method 7
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FTIR Instrument
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Random Errors and Stack Sampling
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Magnitude of the seven components from random errors in stack sampling
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Automated Method 5 analysis
Additional applications for FTIR measurements
Real time air pollution measurements using optical sensing
Future Directions of Stack Testing
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Questions?
Copyright © SRC 2014
Keith Wallace, B. Sc. P.Chem.
Senior Manager Air and Climate
125-15 Innovation Boulevard
Saskatoon, Saskatchewan, Canada
S7N 2X8
Tel: 306-933-9120
Fax: 306-933-7817
www.src.sk.ca
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