Introduction

1. Introduction • Air pollution worldwide is a growing threat to human health and the natural environment • Air pollution may be described as contamination of the atmosphere by gaseous, liquid, or solid wastes or by-products that can endanger life, attack materials and reduce visibility • Some of the questions which might come to mind while thinking about pollution are: • Are we doing something about solving these problems? • Do we know enough about the conditions under which a pollution episode occurs? • What are the regulations? • How to control emissions?

2. Sources Of Air Pollutants • Natural Sources • Volcanoes • Coniferous forests • Forest fires • Pollens • Spores • Dust storms • Hot springs • Man-made Sources • Fuel combustion - Largest contributor • Chemical plants • Motor vehicles • Power and heat generators • Waste disposal sites • Operation of internal-combustion engines

3. Ambient Air • The air all around us

4. Should We Worry About Air Pollution ? • Air pollution affects every one of us • Air pollution can cause health problems and in an extreme case • even death • Air pollution reduces crop yields and affects animal life • Air pollution can soil and corrode materials, and monuments • Air pollution can cause significant economic losses

5. Accidents and Episodes • 1930 -3 day fog in Meuse Valley, Belgium • 1931 -9 day fog in Manchester, England • 1948 -Plant emissions in Donora, Penn, USA • 1952 -4 day fog in London • 1970 -Radionuclide emissions, Three Mile Island, USA • 1984 -Release of Methyl isocynate in Bhopal, India   • 1986 -Radionuclide releases, Chernobyl, Ukraine 

6. Air Quality • Indoor • Radon • Combustion by-products • CO, CO2, SO2, Formaldehyde, Hydrocarbons, NOx, • Particulates, Polyaromatic hydrocarbons • Environmental Tobacco Smoke (ETS) • Volatile organic compounds • Formaldehyde • Biological contaminants • Pesticides • Outdoor • SO2 • CO, CO2 • NO2 • Ozone • TSP • Pb • Toxic pollutants

7. Definition of an Air Pollutant • A contaminant that affects human life, plant life, animal life and property or a contaminant which interferes with the enjoyment of life and property is an air pollutant • Ohio EPA provides a definition of "Air pollutant" or"air contaminant “as particulate matter, dust, fumes, gas, mist, smoke, vapor, or odorous substances.

8. How to define an air pollutant ? • Basis: Chemicals present in the environment • Process: • Use composition of the clean air used as a bench mark. • When the concentration of a chemical is above the concentration of the chemical present in air, it is termed as an air pollutant

9. Physical Forms of Air Pollutants • Gaseous form • Sulfur dioxide • Ozone • Hydro-carbon vapors • Particulate form • Smoke • Dust • Fly ash • Mists

10. Classification of Pollutants • Primary pollutants: remain in the same chemical form, as they are released from a source directly into the atmosphere. • Sulfur dioxide • Hydrocarbons • Secondary pollutants: are a result of chemical reaction among two or more pollutants. • PAN

11. Common Air Pollutants • Sulfur Dioxide • Hydrocarbons • Ozone • Total Suspended Particulate Matter/Fine Particulates • Nitrogen Oxides • Carbon Monoxide • Lead • Carbon Dioxide

12. Toxic Air Pollutants • Toxic air pollutants may originate from natural sources as well as from manmade sources such as stationary and mobile sources • The stationary sources like factories and refineries serve as major contributors to air pollution • The Clean Air Act of 1990 provides a list of 189 chemicals to be regulated under the hazardous air pollutant provisions of the act (See EPA site for current list chemicals)

13. Source Classification Sources may be classified as: (A) Primary Secondary (B) Combustion Non-combustion (C) Stationary Mobile (D) Point:These sources include facilities that emit sufficient amounts of pollutants worth listing Area: all other point sources that individually emit a small amount of pollutants are considered as area sources Natural (biogenic)

14. Source Classification • (E) Classification for reporting air emissions to the public: • Transportation sources: Includes emissions from transportation sources during the combustion process • Stationary combustion sources: These sources produce only energy and the emission is a result of fuel combustion • Industrial sources: These sources emit pollutants during the manufacturing of products • Solid waste Disposal:Includes facilities that dispose off unwanted trash • Miscellaneous: sources that do no fit in any of the above c categories like forest fires, coal mining etc.

15. Air Pollution Index • Air pollution indices were introduced to translate technical information on concentration levels of various pollutants into a simple and easy to understand language for the public • The U.S.E.P.A has developed the pollutant standard index (PSI) for introducing consistency in providing information regarding the air quality throughout the U.S. The system is based on a scale of 0-500 • Index Value is assigned based on the amount of air pollutants in the air and associated health effect

16. Development of an Emission Inventory • Emission Inventory is a study of the pollutant emissions from sources in a given area • Emission Inventories have been developed by: • plant • local environmental agency • national environmental agency • Details for development of an emission inventory depend on: • area of coverage • nature of sources • purpose • Well known emission inventories in US • Inventory of criteria pollutants • Toxic release inventory (TRI)

17. Steps to Develop Emission Inventory • Steps Involved in development of an emission inventory are: • Planning • Data Collection • Data Analysis • Reporting Data

18. Planning • Defines scope and purpose of inventory • Major points considered during this step are: • Pollutants to be enlisted in the inventory are specified along with the methods to collect or estimate data • Use of data and geographical area involved are determined • Legal authority and responsibility of specific groups to acquire data is considered along with an assessment of cost and resources

19. Data Collection • Steps to be taken: • Emissions are classified • Pollutant sources are located and classified • Quality and quantity of materials handled, processed, or burned is determined • Collection Methods: During this stage data may be collected by • Mail survey • Plant inspection • Field surveys • Data from literature: • Industrial files • Government files • Periodicals • Trade journals • Scientific publications

20. Information Collected during Data Collection • General source information - location, ownership, and nature of business • Activity levels - amount of fuel and materials (input) • Amount of production - output of the plant • Control device information - type of pollution control devices • Information required to estimate emissions - temperature, tank conditions, hours of operations, seasonal variation and other data

21. Data Analysis • Check accuracy • Calculation of emission rate is done using: • Monitoring data (most accurate & most expensive) • Emission factors from AP-42 , • Mass balance, and • Engineering calculation

22. Emission Rate • Emission rate is the weight of a pollutant emitted per unit time. • Emission factor is an estimate of the rate at which a pollutant is released into the atmosphere per unit level of activity • To calculate emission rate: EMISSION RATE = [INPUT] x [EMISSION FACTOR] x [APLICABLE CORRECTION FACTORS] x [HOURS OF OPERATION] x [SEASONAL VARIATION]

23. Reporting Data • Information can be filed with the following pollution control agencies: • Local • Regional • National • In US, data gathered by state agencies are reported to the USEPA • Emission data are available from the USEPA’s web site

24. Uses of an Emission Inventory • The Emission Inventory developed may be used for: • Identifying types of pollutants emitted from specific sources. • Determining the magnitude or amount of emissions from those sources • Developing the emissions distribution in time and space • Calculating emission rates under specific plant operating conditions • Finding out the relation of ambient air pollutant concentration with specific sources • Input data for air quality modeling and risk • Determine pollution control options for public health • Estimating cost based on emissions

25. Air Pollution in Asia • Asia represents a major source of air pollution as a result of rapid population growth, explosive industrialization, and few environmental regulations • China: • China is polluted with sulfur dioxide (15 million tons) and particulate matter (20 million tons) because of the use of the high sulfur coal used to generate energy.   • Other Chemicals: • 1. Carbon Dioxide from Industry • 2. Greenhouse Gases from Industry • 3. Nitrogen Oxides from Cars • 4. Acid Rain • With all these problems China has very little air pollution control.

26. Air Pollution in Asia • India: • Most common air pollutant: suspended particulate matter is due to use of coal in power plants • Use of low quality coal produces 45 million metric tons of ash annually • When particulate matter ash is mixed with auto exhaust the emissions across limits resulting in an increase in respiratory diseases and allergies • South Korea: • SO2 is the major pollutant in South Korea, however, it is being controlled by using air pollution control equipment • Hong Kong: • Vehicular emissions contribute to air pollution problems with diesel powered engines being the prime culprit.

27. ppm and µg/m3 relationship where M is the molecular weight of the pollutant gas.