1 One facility, two very different emissions

Module 5. Air Pollutant Emissions in the Mid-Atlantic United States by K.G. Paterson, Ph.D., P.E. ©

3 Did You Know? For PM 2.5 emissions in 2001, only 17 out of the top 100 counties are in the Mid-Atlantic states (VA, WV, PA, MD, DC, DE, NJ) 2001 County Emissions Density (tons/mi 2 ) of PM >0-0.7

4 Emission Module Goals By the end of this module you should be able to: Classify emission types Identify emissions from major source types Describe the trends and patterns of air pollutant emissions in the Mid-Atlantic U.S. Find the tools you need to estimate emissions Find online resources of emission data

5 WHAT ARE EMISSIONS? The amount of pollutant(s) a source puts into the air during a fixed time. Units: mass/time Emissions vary – making air quality management a challenge! Source activity Economic health Population Climate Controls Traffic } These influence source emissions: Time Location Pollutant } Emissions vary over:

6 Emissions classification By pollutant By source type

7 Classification – by Pollutant Some general pollutant categories include Criteria air pollutants Criteria Pre-cursor air pollutants H azardous A ir P ollutants (HAPs) There are 189 of these sulfur dioxide (SO 2 ) nitrogen oxides (NO x ) carbon monoxide (CO) particulate matter (PM 10, PM 2.5 ) ammonia (NH 3 ) volatile organic compounds (VOCs)

8 Classification – by Pollutant An Example: Emissions from North Carolina in 1999: * Point sources only PollutantsEmissions* (lb/yr) All criteria pollutants1,930,000,000 All hazardous air pollutants (HAPs) 329,500,000

9 Classification – by Source Type Stationary - sources with a fixed location Point: usually a large source, often a stack Area: sources that are considered as a group Mobile - sources that move On-road: highway vehicles Non-road: non-highway vehicles

10 Emissions from source types modeled differently Mobile source Point source Area source Gaussian plume model (e.g. ISC-AERMOD) Roadway models (e.g. CALINE, CAL3QHC) Flexible source models (e.g. CALPUFF) Classification – by Source Type

11 Analysis: Emission Classification Question: How many sources can you think of? Action: In a small group, make three lists for examples of air pollution sources: (1) point, (2) mobile, and (3) area Time: 3 minutes

12 Classification – by Source Type Stationary sources Mobile sources Point source Mobile source Area source Examples: on-road: gas, diesel; off-road: marine, air, agricultural Examples: power plant, chemical plant, etc. Examples: gas stations, dry cleaners, fireplaces, lawn mowers, tanks farms, etc. Stationary Mobile

13 Emission Classification Sulfur Dioxide (SO 2 ) Power plants are major sources of (SO 2 ) They are stationary (point) sources (2002 data)

14 Emission trends are not the same everywhere. Reductions in SO 2 have been widespread but not universal. mapgallery/mg_total_utility_so2.html Emission Trend Sulfur Dioxide (SO 2 )

15 Passenger vehicles are a major source of NO x. These are mobile (on-road) sources. Emission Classification Nitrogen Oxides (NO x ) (2002 data)

16 Trends in NO x emissions have not been uniform in the Mid-Atlantic, but some of the greatest reductions in the U.S. have been in the East Emission Trend Nitrogen Oxides (NO x )

17 Analysis: Classification & Trend

18 Question: What are the temporal and spatial differences between NO X and SO X emissions in the Eastern United States? State why you think those temporal and spatial differences exist. Action: In a small group examine the maps of the Eastern USA NO X and SO X emissions over time and report observations. Time: 5 minutes. Analysis: Classification & Trend

19 MOBILE6 is a model for predicting emissions from vehicles. Capabilities: Pollutants predicted: CO, CO 2, NO x, PM, toxics, hydrocarbons Vehicle types: cars, trucks, motorcycles Operating conditions: speed, temperature, etc. Fuel types: gasoline, diesel Emission Estimation

20 Fugitive sources that often contribute to ambient particulate matter: Construction sites Agriculture Unpaved roads PM 2.5 Emissions 2000 Source: Bureau of Transportation Statistics Emission Classification - Miscellaneous

21 Emission Estimation After identifying possible sources of air pollutant emissions, the next challenge is quantifying their magnitude. Methods: Direct measurement CEM, stack test Indirect measurement Mass balance Process modeling Tanks and Mobile6 Emission factor modeling AP-42

22 MOBILE6 is a model for predicting emissions from vehicles. Capabilities: Pollutants predicted: CO, CO 2, NO x, PM, toxics, hydrocarbons Vehicle types: cars, trucks, motorcycles Operating conditions: speed, temperature, etc. Fuel types: gasoline, diesel Emission Estimation - Example

23 Further Learning Emissions Measurement Center, National Emission Inventory (NEI) Database for Criteria and Hazardous Air Pollutants, Scorecard, an online tool to investigate pollution in your neighborhood, Emission models, Compilation of Air Pollutant Emission Factors, Volume 1: Stationary Point and Area Sources, AP 42, AirData, online access to emissions at the county level and up, A Guide to Mid-Atlantic Regional Air Quality, Part IV: Pollution Sources, pp MidAtlantic_RegAQ_Final.pdf

24 Emission Module Goals By the end of this module you should be able to: Classify emission types Identify emissions from major source types Describe the trends and patterns of air pollutant emissions in the Mid-Atlantic U.S. Find the tools you need to estimate emissions Find online resources of emission data

25 Thanks for making this a great class!