CE 5326 AIR POLLUTION CONTROL Fall 2008

1. CE 5326 AIR POLLUTION CONTROLFall 2008 Session 4: Air Pollution Measurements Air Pollution Effects

2. H.W. #4: Due Sep. 24, 2008 • De Nevers Problems 4.7; 4.8; 4.15; 4.16;4.17 • Reading Assignment: • De Never: Chapter 4 • U.S. EPA siting regulations (Appendices D and E to Part 58), p61316-61328 Air Pollution Effects

3. Ambient Monitoring • Measurements of Air Pollutants. • Time-integrated Air Monitoring • Particulate Matter • Hi-vol: 1 m3/min • Mid-vol: 100 l - 1 m3/min • Low-vol: 10 l - 100 l /min • Personal: < 10 l/min • Vapor • Grab samples • Canister • Media • Continuous Air Monitoring Air Pollution Effects

4. Ambient Monitoring • Meteorological Measurements. • Surface Meteorology • Wind Direction • Wind Speed • Atmospheric Temperature • Atmospheric Humidity • Atmospheric Pressure • Vertical Temperature Profile • Upper Air Measurement • Balloon Measurements • Radiosonde: • Rawinsonde: • Rocket-fired Equipment falling through the atmosphere: • Remote Sensing: Air Pollution Effects

5. Air Monitoring Objectives • Provide air pollution data to the general public in a timely manner • Support compliance with NAAQS and emission strategy development • Support for air pollution research studies Air Pollution Effects

6. Types of Air Monitoring Sites • Highest concentration • Population-oriented community exposure • Source impacts • Background • Regional transport • Welfare impacts on visibility, vegetation, wild life, etc Air Pollution Effects

7. Air Monitoring Design • Stage of Air Monitoring • Pre-construction/remediation (Background) Monitoring • Post-construction/remediation Monitoring • Monitoring during Construction/remediation Activities • Pollutants to be Monitored • Criteria Pollutants • Non-criteria Pollutants • Monitoring Locations • Case I: Free from the impacts from other sources • Case II: Multisource emissions in flat terrain • Case III: Multisource emissions in complex terrain Air Pollution Effects

8. Air Monitoring Design • Duration • Sampling Methods • Sampling Locations • Sampling Plan • Sampling Media Air Pollution Effects

9. Distance to PM Sampler Air Pollution Effects

10. Distance to Other Samplers Air Pollution Effects

11. Siting Summary Air Pollution Effects

12. Isokinetic Sampling When the sampling inlet axis is aligned parallel to the air stream and the air velocity entering the probe is the same as the free stream velocity approaching the inlet, the sampling procedure is called isokinetic sampling. Air Pollution Effects

13. Anisokinetic Sampling Air Pollution Effects

14. Anisokinetic Sampling: Superisokinetic Air Pollution Effects

15. Anisokinetic Sampling: Subisokinetic Air Pollution Effects

16. Dichotomous Air Monitors Air Pollution Effects

17. Dichotomous Air Monitors Air Pollution Effects

18. Principle of Operation • Operation Principle Large particles with greater inertia cannot follow the sharp turn made by the air steam and continue to move in their initial directions and therefore are separated from the air stream. • Virtual Impaction The air stream is forced to make a turn not by physical obstruction but by the reduction of flow velocity, a virtual impaction. • Aerodynamic Diameter The behavior of a particle in the air stream is based on its aerodynamic properties rather than the physical size and shape. Air Pollution Effects

19. Conceptual diagram of particle deposition mechanisms Air Pollution Effects

20. Schematics of Dichotomous Air Monitor PM10 inlet Air Pollution Effects

21. Example for Dichotomous PM Measurements Cc= 30 μg/m3 CF= 10 μg/m3 FT= 16.7l/min or 1m3/hr t = 24 hrs MF= CF· FF· t = (10 μg/m3)· (0.9 m3/hr)· (24 hrs) = 216 μg MC= (CC· FT· t) + (CF · FC· t) = (30 μg/m3)· (1.0 m3/hr)· (24 hrs) + = (10 μg/m3)· (0.1 m3/hr)· (24 hrs) = 720 μg + 24 μg = 744 μg Mc= 744 μg MF= 216 μg Air Pollution Effects

22. Derivation of the Concentration Equations FT CF, CC FF FC t = sampling time, hr A= Actual mass to be collected, μg M= mass collected on the filter, μg F= flowrate, m3/hr Subscript: C: coarse particulate F: fine particulate T: total Air Pollution Effects

23. Bioassay Implication • PM2.5 Filter The mass collected on the PM2.5 filter represents FF/FT of the actual ambient concentration. Under standard operating conditions, FF/FT is 0.9 (or 90 %). In other words, if the average ambient PM2.5 concentration is 10 μg/m3, the dose retained on the filter for bioassay analysis is equivalent to an ambient PM2.5 concentration of 9 μg/m3. • PM10-2.5 Filter The mass collected on the PM10-2.5 filter represents the sum of actual coarse PM (PM10-2.5) plus a fraction of fine PM (PM2.5), an amount of (FT-FF)/FT collected during the sampling period. Under standard operating conditions, (FT-FF)/FT is 0.1 (or 10 %). In other words, if the average ambient PM10-2.5 concentration is 30 μg/m3 and PM2.5 concentration is 10 μg/m3, the dose retained on the filter for bioassay analysis is equivalent to 30 μg/m3 of PM10-2.5 plus 1 μg/m3 of PM2.5. Air Pollution Effects

24. Data Processing for Chemical Concentrations • Determine the concentration of each compound on either filter (CF or CC) by multiplying the compound concentration in solution by the amount of solution • Determine the air concentration of each compound in either size category by using paired concentrations and the two dichotomous equations. Air Pollution Effects

25. Composite Samples • Composite each pair of PM2.5 and PM10-2.5 samples for bioassay effects of PM10 for the same sample duration at the same location. • Composite multiple PM2.5 filters for bioassay effects of concentrations at k·(FF/FT)·∑CF, where k is a dilution factor. • Composite multiple PM10-2.5 filters for bioassay effects of concentrations at k·{(FT-FF)/FT)·∑CF + ∑CC}, where k is a dilution factor. • May be used together to evaluate incremental effects. Air Pollution Effects

26. Uncertainties • Instrumentation • Loss of mass • Size cut-off • Humidity • Field Operations • Flow Rates • Filter Handling • Laboratory Operations • Gravimetric Weighing • Temperature • Humidity • Electrostatics Air Pollution Effects