Garnet Erdakos, Prakash Bhave, Heather Simon, George Pouliot

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Using CMAQ to Evaluate Air Quality Impacts of
Nano-Cerium Diesel Fuel Additives

• Garnet Erdakos, Prakash Bhave, Heather Simon,
  George Pouliot

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Why Nano-Cerium?
http//www.epa.gov/nanoscience/
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Research Questions

• What are the potential exposure levels to CeO2
  nanoparticles (NP) due to use of nano-cerium
  (nCe) diesel fuel additives?
• What effects do nCe fuel additives have on diesel
  emissions (e.g., PM, VOC, HAPs, etc.)?
• What effects do nCe fuel additives have on
  atmospheric chemistry?

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Research Strategy

• Estimate changes in diesel emissions due to
  nano-cerium (nCe)-based fuel additives
• Estimate resulting impact on regional-scale air
  quality using CMAQ by comparing
• Base case simulation with standard emissions
• nCe case simulation with modified diesel
  emissions using best estimates from available
  literature on nCe

5
Literature Review on nCe Effects on Diesel
Emissions

• 33 reports and articles found through DIALOG and
  Internet searches
• 10 studies analyzed for this work (all HD
  engines)
• 3 nCe additive products 10 nCe dosing levels 6
  engine types 5 different testing procedures
  different base fuels
• 14 data sets PM (n 50), CO (n 34), VOC (n
  35), NOx (n 35)

n of data points
6
Summary of Literature Data from Diesel Emissions
Studies
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Summary of Literature Data from Diesel Emissions
Studies
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Summary of Literature Data from Diesel Emissions
Studies
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Summary of Literature Data from Diesel Emissions
Studies
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Selection of Data for CMAQ Simulations
avg -20
avg -2.5
avg 22
avg 16
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Example Illustration of Emissions Changes
National Emissions in 1999 (thousand short tons) National Emissions in 1999 (thousand short tons) National Emissions in 1999 (thousand short tons) National Emissions in 1999 (thousand short tons) National Emissions in 1999 (thousand short tons) National Emissions in 1999 (thousand short tons) National Emissions in 1999 (thousand short tons) National Emissions in 1999 (thousand short tons) National Emissions in 1999 (thousand short tons) National Emissions in 1999 (thousand short tons)
Diesel Diesel Diesel Modified Diesel Modified Diesel
Pollutant Total On-Road Non-Road of Total On- Off-Road of Total
CO 97,441 2,230 1,302 3.6 4,097 4.2
NOx 25,393 3,635 2,707 25.0 6,183 24.5
PM10 20,634 189 253 2.1 354 1.7
VOC 18,145 289 372 3.6 806 4.4
PM2.5 6,773 166 233 5.9 319 4.8
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CMAQ Simulation Details

• CMAQ v4.7
• Monday, August 7 Sunday, August 13, 2006,
  including three days of spin-up
• 12 km EUS domain, 240 x 279 grid cells, 24 layers
• 2006 MM5 meteorology
• SMOKE emissions 2006 CDC PHASE runs
• nCe Case modifications to emissions for on-road
  and non-road diesel sources

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Emissions Comparison
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Emissions Comparison
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Emissions Comparison
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CMAQ Simulation Results
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CMAQ Simulation Results
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Summary

• Diesel emissions, and thus changes due to nCe
  fuel additives, are highly variable depending on
  engine type, base fuel characteristics, and
  testing procedure
• Systematic emissions tests using a single base
  fuel and test procedure with a population of
  engine types are necessary to better estimate nCe
  effects
• nCe diesel fuel additives tend to decrease mass
  emissions of PM at all Ce concentrations for Ce
  25 ppm, VOC and CO emissions tend to increase,
  while NOx emissions are reduced slightly
• Preliminary results show reductions in average O3
  and PM concentrations due to nCe diesel fuel
  additives

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Future Work

• Perform additional CMAQ simulations to explore
  impacts of variability in nCe additive affects on
  diesel emissions, as well as seasonal variations
• Modify emissions of individual PM and VOC species
  (e.g., EC, benzene, HAPs)
• Consider locomotive, marine, and stationary
  diesel sources
• Model near-road fate and transport of CeO2
  nanoparticles

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Acknowledgements

• Prakash Bhave
• George Pouliot
• Heather Simon
• Shawn Roselle
• Rob Pinder
• David Wong
• Wyat Appel
• Rohit Mathur
• Ken Schere
• Marion Hoyer
• Jim Caldwell
• Amanda Evans
• J. Michael Davis

Jason Weinstein Tad Kleindienst Bill Linak Thomas
Long John Kinsey Kevin Dreher Michele
Conlon Maria Costantini Barry Park Steven
Deutsch Jan Czerwinski David Green
EPA/ORD/NERL/HEASD
EPA/ORD/NRMRL/APPCD
EPA/ORD/NERL/AMAD
EPA/ORD/NHEERL
EPA/ORD/NERL
HEI
GBP Consulting
Rhodia Silcea NA
EPA/OAR/OTAQ
AFHB, HTL, Biel
EPA/ORD/OSP
Kings College London
EPA/ORD/NCEA