1. 1 Module 1 Air Pollution Overview Material Balances

2. 2 MCEN 4131/5131 Modulel 11/23/06 What are we doing in class today? Preliminaries –Handouts for Thursday’s SIP project –Office hours OK? –Do you have a clicker? –Is it registered? –Solutions to odd-numbered HW problems in back of book, remember you can work in groups –Do not do HW problem 1.21 Review material and quiz In-class problems –Conversions –Material balances

3. 3 MCEN 4131/5131 Modulel 11/23/06 Educational Objectives Name the NAAQS criteria pollutants and the standard values for PM2.5, CO, O3 Define Prevention of Significant Deterioration (PSD) Describe and apply the New Source Performance Standards (NSPSs) Describe the major air pollutants of concern, their major sources and why they are of concern (PM, SO2, NOx, VOCs and photochemical oxidants, CO) Apply the ideal gas law Convert from ppm to  g  m 3 Solve material balance problems

4. 4 MCEN 4131/5131 Modulel 11/23/06 Clicker Question Which of the following is not a criteria pollutant? a. Particulate lead b. Nitric oxide c. PM2.5

5. 5 MCEN 4131/5131 Modulel 11/23/06 Air Pollution Control Strategies The Emission Standard (e.g. NSPS) –Focuses on the emitter –Best available control technology (BACT) –Not very cost effective, but easy to enforce The Air Quality Standard (e.g NAAQS) –Focuses on human health and welfare effects –Need to tie to emissions to enforce Emissions Tax (e.g. miles-specific vehicle tax, Carbon emissions tax) –Economic incentives to pollute less Market Control, Emission Rights (e.g. carbon trading) –Polluters trade amongst themselves a limited amount of credits

6. 6 MCEN 4131/5131 Modulel 11/23/06 Emissions Trading Implemented in 2005 in Europe –Goal is to reduce greenhouse gases and is based on permits for carbon use –Industry allocated targets for emissions of CO2 –if they beat these they will be able to sell permits to other businesses –If companies want to exceed their pollution allocations they will pay penalties or buy permits from other businesses –UK estimates that scheme will cost 1.2 billion USD http://www.co2e.com/

7. 7 MCEN 4131/5131 Modulel 11/23/06 Clicker Question In the CAAA of 1977, PSD of air quality in regions cleaner than the NAAQS was added. A Class I area was defined as: a. An urban area b. Farmland c. A pristine area

8. 8 MCEN 4131/5131 Modulel 11/23/06 New Source Review Permitting Program President Bush made overhauling the NSR one of his top environmental prioritiesNSR National Academy of Sciences reviewed Bush’s NSR program –Suggests that Bush’s plans to reform the CAA are likely to allow higher emission levels at individual electric utility plants than the current NSR program Clear Skies Bill proposed in 2005 but never passed in congressClear Skies Bill passed EPA implemented CAIR in 2005CAIR

9. 9 MCEN 4131/5131 Modulel 11/23/06 You the Engineer and Permitting The CAAA of 1990 requires that states administer permits for sources that potentially emit a controlled pollutant at a rate greater than the standard, for that type of source You are required to look at CU’s Power house, which produces electricity and steam (heating) for CU and the Williams Village Dormitory

10. 10 MCEN 4131/5131 Modulel 11/23/06 SPECS Because it has the potential to emit: >100 tons/yr of NOx >100 tons/yr of CO And it is in a non-compliance area for ozone (http://www.compliancepublishers.com/c c/cc1103.htm)http://www.compliancepublishers.com/c c/cc1103.htm) Then it must get an operating permit

11. 11 MCEN 4131/5131 Modulel 11/23/06 What you do You examine the plant, note type of equipment and find the turbines are subject to NSPS Emissions limits for this kind of turbine are already outlined (NOx) You recommend low-excess-air firing for the combustors (chapter 16, p 508) You also require the plant install equipment for measuring flowrates, pollutant concentrations, etc. You outline a reporting schedule

12. 12 MCEN 4131/5131 Modulel 11/23/06 Clicker Questions What is Title I of the 1990 CAA? a. Mobile sources b. Acid deposition c. NAAQS What is the PM2.5 standard? a. 15  g/m 3 annual, 65  g/m 3 24 hour b. 50  g/m 3 annual, 1500  g/m 3 24 hour

13. 13 MCEN 4131/5131 Modulel 11/23/06 Transport, Dilution, Alteration Removal Source ExposureTransport and Fate ACME Widget Co. Install controls here

14. 14 MCEN 4131/5131 Modulel 11/23/06 Sources Air pollution sources include anything that releases anything to the air. –Power plants – electricity production –Factories, refineries –Painting –Cars and trucks –All buildings – cleaning products, heating, cooking,… –All people let’s look at some of the prominent pollutant species.

15. 15 MCEN 4131/5131 Modulel 11/23/06 Particulate Matter Caused by –Materials-handling processes –Combustion –Gas conversion reactions Affects –Visibility –Human health –Soiling of artifacts, electronics Fine particles

16. 16 MCEN 4131/5131 Modulel 11/23/06 London Fog Donora, PA Chimney sweeps Fine PM is associated with mortality

17. 17 MCEN 4131/5131 Modulel 11/23/06 Sulfur Dioxide Vegetation damage, respiratory irritation, acid rain

18. 18 MCEN 4131/5131 Modulel 11/23/06 Clicker Question What is a main product of reactions that involve VOCs and NOx and sunlight? a. Carbon monoxide b. Benzene c. ozone

19. 19 MCEN 4131/5131 Modulel 11/23/06 Nitrogen Oxides Smog, vegetation damage, respiratory irritant, visibility

20. 20 MCEN 4131/5131 Modulel 11/23/06 Carbon monoxide Health effects - slight headaches to death (>500/yr die due to fuel-burning appliances, 1000’s get sick) Residential heating Important!

21. 21 MCEN 4131/5131 Modulel 11/23/06 Tools of the Trade Ideal gas law Material balance Energy balance

22. 22 MCEN 4131/5131 Modulel 11/23/06 STP Standard temperature value in air pollution is? 25 °C Standard pressure value is? 1 atm

23. 23 MCEN 4131/5131 Modulel 11/23/06 MW Calculation For each molecule, find (memorize) atomic weight from periodic tableperiodic table Molecular weight = sum of atomic wts Units are g/gmol, lb/lbmol, kg/kgmol

24. 24 MCEN 4131/5131 Modulel 11/23/06 Ideal Gas Law Mass concentration Partial Pressure (can be expressed as ppm)

25. 25 MCEN 4131/5131 Modulel 11/23/06 Clicker question (group) TOOL: Use the ideal gas law to convert between ppm and  g/m 3 Convert the NO 2 AQS of 100  g/m 3 to ppm DATA: T=23 C, R=0.08206 atm-L/K-mol, P = 1 atm Molecular weights? a. 0.35 ppm b. 0.053 ppm c. 4.2 ppm

26. 26 MCEN 4131/5131 Modulel 11/23/06 …and again… Now convert a CO concentration of 35 ppm to  g/m 3.

27. 27 MCEN 4131/5131 Modulel 11/23/06 Clicker question Given a flow rate of 30 L/min at 20C and 790 mm Hg What is the flow rate at 200C and 730 mm Hg a. 52 L/min b. 45 L/min c. 17 L/min

28. 28 MCEN 4131/5131 Modulel 11/23/06 Material Balances Mass and heat balances are at the core of unit operations Mass is neither created nor destroyed, may change form like in a chemical reaction Same with energy