&EPA
Commerical, Industrial and
   Residential Sectors
      United States
      Environmental Protection
      Agency
   Emissions from  Biofuels Burned in


Small Industry/Commercial  Boilers


Background
As interest in reducing net carbon dioxide (CO2) emissions grows, there is a corresponding increase in use of fuels
derived from renewable sources, particularly from biomass. One practical consideration that those who are evalu-
ating the potential for biofuel use must address is the impact on regulated emissions such as carbon monoxide
(CO), oxides of nitrogen (NOX), particulate matter (PM), sulfur dioxide (SO2), volatile organic compounds (VOCs),
and hazardous air pollutants (HAPs). Subsequently, regulatory agencies are being asked to provide guidance to
boiler owners and operators who are interested in switch-
ing from fossil fuels to biofuels, and air quality manag-
ers are typically faced with providing this guidance with
limited information regarding how emissions of regulated
emissions may change.

The objective of this research effort is to quantify changes
in emissions that result from a change in fuels from a com-
monly used fossil fuel to biofuels that have similar combus-
tion characteristics. A No. 2 (distillate) fuel oil will be used
as the baseline fuel in a commercially available, 2.9 million
Btu/hr (0.85 MW) firetube boiler, such as is used in light
industrial, commercial, or institutional applications for low-
pressure (15 psig) steam production. Emissions of CO, NOV,
                                         A
and SO2 will be measured using continuous emission moni-
tors (CEMs), and samples will be collected to determine
emissions of PM, VOCs, and selected HAPs. The boiler will
then be operated using two different biodiesel fuels, one
vegetable-based and one animal-based, and the emission
measurements will be repeated to determine changes due
to the use of the biofuels. The vegetable-based biodiesel
will also be blended with the No. 2 fuel oil at several blend
ratios to evaluate the impact on emissions of blended fossil
and biofuels. If possible, measurements will also be taken
to evaluate the impact of biofuels on boiler operating ef-
ficiency.


Projected Impact/Outcomes

The results of these tests will be used to enable EPA's Office
of Air and Radiation to provide more accurate guidance to boiler owners and operators regarding the potential
emissions changes when switching to biofuels. This guidance will minimize the potential for emissions increases
due to increased use of renewable fuels in these types of boilers, thereby ensuring that approaches to CO2 mitiga-
tion can be taken that are environmentally sound.
Office of Research and Development
National Risk Management Research Laboratory, Air Pollution Prevention and Control Division

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                                                                            Commerical, Industrial and
                                                                               Residential Sectors
Results

 This research will yield data on exhaust concentrations and
 emission rates of CO, NO, SO2, and PM, as well as several
 hazardous air pollutants. These data will be the basis for
 development of emission factors (mass of pollutant emitted
 per unit of fuel input) that are used by regulatory agencies
 and industries to estimate annual emissions. Qualitative
 information on boiler performance during operation with
 biofuels will also be reported.

Relevant  Publications
Miller, C.A.; Ryan, J.V.; Lombardo,T. 1996. Characterization of
air toxics from an oil-firedfiretube boiler; J Air Waste Manage
Assoc, 46, 742-748.

Miller, C.A.; Linak, W.P.; King, C; Wendt, J.O.L 1998. Fine
particle emissions from heavy fuel oil combustion in a firetube package boiler; Combust Sci Technol 134,
477-502.

Miller, C.A.; Srivastava, R.K. 2000. The combustion of Orimulsion and its generation of air pollutants; Progress
iEnergy Combust Sci 26,131-160.
Clients
  EPA Office of Air and Radiation

  State and local air quality management agencies
Contacts
 Dr. Andy Miller,

 miller.andy@epa.gov

 919.541.2920
                           Dr. Miller joined EPA in 1991, after receiving a Ph.D. in Mechanical Engineering at
                           North Carolina State University. His research focus has been on characterization of
                           emissions from combustion sources, including work on emissions from the com-
                           bustion of emulsified fuels. He has worked in several other related areas, including
                           development of NOx controls using combustion modification and application of
                           artificial intelligence to control emissions from hazardous waste incineration. Dr.
                           Miller is currently the leader of the Biofuels/Bioenergy Research Team for NRMRL.

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