Emissions%20from%20Prescribed%20Burning%20in%20Georgia

1
Emissions from Prescribed Burning in Georgia
Sangil Lee1, Karsten Baumann2, Donald R. Blake3,
Armistead Russell1, Mark Clements4 1School of
Civil and Environmental Engineering, Georgia
Institute of Technology, Atlanta, GA 2School of
Earth and Atmospheric Sciences, Georgia Institute
of Technology, Atlanta, GA 3Department of
Chemistry, University of California, Irvine,
CA 4Southeast Regional Office, Installation
Management Agency, U.S. Army, Fort McPherson, GA
Introduction According to EPA emission inventory
(1999) 18 of primary PM2.5 emissions comes from
forest fires (wildfire and prescribed fire),
11.4 and 5, for CO and Volatile Organic
Compounds (VOC), respectively. Forest fire is
significant source of air pollutants. However,
they are not well characterized in terms of
chemical composition of its emissions. Here, the
emissions from prescribed fires were collected
during prescribed fires at three different
locations around Georgia. Part of this work was
funded by the EPA/DOD Region 4 Pollution
Prevention Partnership Small Grants Program and
the U.S. Army Corps of Engineers via Engineering
Environment, Inc. subcontract NC03-05SUB01.
PCM measurements
Number of samples SRS (4), Fort Gordon (2),
Fort Benning (2)
Gaseous Emissions measured by Tandem Denuders at
each location
Particulate Emissions

• Site description
• Fort Benning, Columbus, Georgia (April 2004)
• Fort Gordon, Augusta, Georgia (April 2004)
• Savannah River Site, Aiken, South Carolina
  (February 2004)
• Fort Benning and Gordon are military bases that
  are located at southwest and southeast of
  Atlanta, GA, respectively. Savannah River Site is
  located at south of Aiken, SC, which borders the
  Savannah river for 30 km. Prescribed fire is
  widely used for land management to maintain
  healthy longleaf pine forests and thus protect
  endangered species (e.g. Red cockaded woodpecker
  ).

Percent Mass of Chemical Composition of
Particulate Emissions

• Measurement methods
• Particulate emission measurements
• Custom-designed particulate composition monitor
  (PCM)
• Samples were collected after fires mostly
  flaming stage (no separate measurement for
  flaming vs. smoldering stage)
• Channel 1 Cyclone Dsc Dpa TGsc
• Channel 2 Carbon Denuder Cyclone Q XadQ
  (Fort Benning, Gordon April 2004)
• Channel 2 Cyclone Q Q (Savannah River Site
  February 2004)
• Teflon filters were analyzed by IC for water
  soluble ionic species and by ICP-MS for trace
  metal
• elements.
• Glass filters (coated by sodium carbonate) were
  analyzed by IC for semivolatile water soluble
• ionic species (e.g., NO3-, CH3COO- etc)
• Quartz filters were analyzed by TOT
• Dsc, Dpa URG annular denuders
  coated by sodium carbonate and phosphoric acid,
  respectively.
• T Teflon filter.
• Gsc Glass filters coated by
  sodium carbonate.
• Q, Xad Q Quartz and Xad
  coated Quartz filters.
• High Volume sampler (only for Fort Benning and
  Gordon) still in progress
• Samples were collected after fires mostly
  flaming stages
• (no separate measurement for flaming vs.
  smoldering stage).

Averaged Chemical Composition of Particulate
Emissions
Comparisons with Other Biomass Burnings in USA
Emissions were calculated after subtracting
background levels. Gaseous and particulate
emissions vary from location to location. In
general, NH3, HONO, acetic and formic acids
increase Considerably after prescribed fires at
all three locations. OC is a dominant species of
particulate matter mass (44 70 ). It is
followed by EC and K (3 4.5 and 2.9 4.6
, respectively). The percent masses of
particulate chemical species are very different
for biomass burnings
(Reference Chow et al., 2004, Chemosphere
Schauer et al., 2001, EST Pine et al., 2002,
EST)
Canister Measurements
Number of samples Fort Benning Flaming (5),
Smoldering (5), Fort Gordon Flaming (4),
Smoldering (3), Background (19)

• Gaseous emission measurements
• Denuders (PCM Channel 1)
• Denuder extractions were analyzed by IC for
  gases (e.g., SO2, NH3, HNO3, HONO, HCl,
  CH3COOH,CHCOOH, (COOH)2)
• Evacuated stainless steel canisters (only Fort
  Benning and Gordon, February April 2003)
• Samples were collected before fires, during
  flaming, and smoldering stage (CO, CO2,CH4,
  non-methane hydrocarbons (NMHC) etc)
• analyzed by GC/(MS,FID, ECD)

Concentrations of gaseous emissions increase by
an order of 10 1000 after fires. In general, the
concentrations are higher during flaming than
smoldering
Emission Factors of Gases and Particulate Matter
?X excess mass concentration ?C excess carbon
concentration NMOC non-methane organic
compounds PC particulate carbon Assume carbon
contents of biomass 50
CE ()
Combustion efficiency (CE) shows clear difference
between flaming and smoldering stage, 9192 and
8182 , respectively
Emission factors (EF) of halogenated hydrocarbons
and organic nitrates are multiplied by 1000
PCM and canister measurements have not been done
simultaneously, and no PCM sampling at different
burning stage (flaming vs. smoldering). The same
averaged values were used to calculate emission
factors of particulate matter for flaming
and smoldering. the patterns of emission factors
are very similar between flaming and smoldering.
comparing with emission factors from Africa
prescribed burnings both patterns are also very
similar.
(References Sinha et al, 2004, JGR)
Conclusions

• Particulate Emissions, in terms of mass, vary at
  different location from 1413 to 2345 mg/m3
  (average 1531 - 763 mg/m3). However, OC
  (organic carbon)
• is a dominant species, averaging 56 - 11
  . It is followed by EC (4.0 - 0.7 ), K (3.7 -
  0.9), Si (3.1 - 3.3), Acetate (1.2 - 1.2).
• The percent masses of particulate chemical
  species are very variable for different biomass
  burnings although OC is the most dominant
  species.
• In general, emission factors are higher for
  smoldering than flaming whereas absolute
  concentrations are higher for flaming.
• This trend becomes stronger as the carbon
  contents increase for NMHCs.
• The patterns of emission factors of this study
  and African prescribed burnings are very similar.