1. NOx Emission Factors Robert Fowler ME 449: Sustainable Air Quality April 2001

2. Table of Contents Objective of work Major contributors for NOx emissions Emission factor equations Data sources Summary Recommendations

3. Objective Show emission factor calculations Method Web search and EPA manual foe emission factors AP-42AP-42

4. Major Contributors to NOx Transportation - gas and diesel vehicles Fuel combustion - power plants Industrial Processes - waste disposal/petroleum refinery

5. Transportation emission equation Driving factors: Emission factor and vehicle miles traveled Equation for emission factor EF = (BER*OMTCF+OMTTAM)*SALCHF*TF BER - basic emission rate OMTCF - operating mode/temperature correction factor OMTTAM - Tampering offset SALCHF - Speed correction factor TF - Travel fraction To get the emission inventory: EI = EF * VMT

6. Fuel combustion emission equation Driving factors: emission factor & quantity of fuel consumed Emission factor: Mass of pollutant/mass of fuel (or output) Boilers - lb NOx/ton fuel ICE’s - lb NOx/hp-hr power output and lb NOx/MMBtu fuel input Gas turbines - lb NOx/MMBtu fuel Stationary diesels - lb NOx/hp-hr power output and lb NOx/MMBtu fuel input Stationary dual fuel engines - lb NOx/hp-hr power output and lb NOx/MMBtu fuel input

7. Industrial Processes emission equations Driving factors: Emission factor and mass of fuel burned Emission factor: mass pollutant/mass (or volume) fuel Solid waste disposal - kg NOx/Mg refuse or lb NOx/ton refuse Sewage sludge - kg NOx/Mg refuse or lb NOx/ton sludge Medical - kg NOx/Mg refuse or lb NOx/ton refuse Open burning - kg NOx/Mg refuse or lb NOx/ton refuse Auto Body - kg NOx/Mg refuse or lb NOx/ton refuse Evaporation losses - g/drum or lb/drum Petroleum refineries - kg NOx/10 3 L fresh feed; lb NOx/1000 bbl (barrel) fresh feed; kg NOx/1000 m3 gas burned; lb NOx/1000 ft3 gas burned; kg NOx/103 L refinery feed; lb NOx/1000 bbl refinery feed

8. Data Source Transportation data - EPA AP-42 Vol II Appendix G http://www.epa.gov/otaq/ap42.htm Fuel combustion and industrial processes - EPA AP-42 Vol I Chapter 1-5, 11 http://www.epa.gov/ttn/chief/ap42/ch01/ http://www.epa.gov/ttn/chief/ap42/ch02/ http://www.epa.gov/ttn/chief/ap42/ch03/ http://www.epa.gov/ttn/chief/ap42/ch04/ http://www.epa.gov/ttn/chief/ap42/ch05/ http://www.epa.gov/ttn/chief/ap42/ch11/

9. Summary The major contributors of NOx emissions are transportation, fuel combustion, and industrial processes Emission inventory is determined by the emission factor times the driving force Data came from EPA AP-42 manual Vol I & II Conclusion Still don’t know what the equations are to determine the numbers for the emission factors EPA website very useful obtaining the emission factor for whatever fuel you need it for

10. Recommendations for improving emission factors The uncontrolled emission factors can be reduced by better controls within the system prior to exhaust The controlled emission factors can be reduced by better scrubbers and filters at the exhaust