United States
Environmental Protection
Agency
Industrial Environmental Research
Laboratory
Research Triangle Park NC 27711
Research and Development
EPA-600/S7-81 -003b Apr. 1981
Project Summary
Emissions Assessment of
Conventional Stationary
Combustion Systems:
Volume IV.
Commercial/Institutional
Combustion Sources
N. F. Surprenant, P. Hung, R. Li, K. T. McGregor, W. Piispanen, and S. M.
Sandberg
This report characterizes air emis-
sions from commercial/institutional
external combustion sources and
reciprocating engines and is the fourth
of a series of five project reports
characterizing emissions from con-
ventional combustion sources. The
emissions characterization of commer-
cial/institutional combustion sources
was based on a critical examination of
existing data, followed by a modified
Level I sampling and analysis approach
to resolve data gaps. The major devia-
tion from Level I procedures was the
addition of QC/MS analysis for poly-
cyclic organic matter (POM)- Tests
were conducted at 22 external com-
bustion and' 6 internal combustion
sites.
The results of the environmental
assessment indicate that air emissions
from these sources represent a poten-
tial environmental hazard. Emissions
of criteria pollutants, with the excep-
tion of carbon monoxide, from most of
the source categories tested are en-
vironmentally significant. Paniculate
sulfate and SO3 emissions from the
coal- and wood-fires sources are also
significant. In addition, emissions of
several trace elements are of concern:
aluminum, barium, beryllium, calcium,
chlorine, cobalt, chromium, copper,
fluorine, iron, potassium, lithium,
sodium, nickel, phosphorus, lead,
silicon, and vanadium from coal-fired
external combustion sources; nickel
from distillate oil sources; and nickel,
chlorine, chromium, and vanadium
from residual oil sources. Several
potentially hazardous POM compounds
were tentatively identified in the emis-
sions from solid fuel-fired sources,
particularly from the one wood-fired
stoker tested. Flue gas emissions of
POM from solid fuel-fired sources will
require further study to positively
identify the POM compounds emitted.
This Project Summary was developed
by EPA'sIndustrial Environmental Re-
search Laboratory. Research Triangle
Park, NC,to announce key findings of"
the research project that is fully docu-
mented in a separate report of the
same title (see Project Report ordering
information at back}.
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Introduction
Emissions from commercial/institu-
tional external combustion sources for
space heating and commercial/institu-
tional internal combustion reciprocating
engines are characterized in this report.
The approach involves a critical review
of existing emission data, followed by
the conduct of a sampling and analysis
program to fill gaps in the data base and
to identify additional data needs. Specif-
ically, the objectives of this program
were:
to compile and evaluate available
air emissions data from commer-
cial/institutional stationary con-
ventional combustion processes,
to acquire needed new emissions
data from field tests of selected
sources using modified Level I
procedures,
to characterize air emissions from
commercial/institutional station-
ary conventional combustion
processes, using both the existing
data base and field test results, and
to determine additional data needs,
including identification of specific
areas of data uncertainty.
Level I procedures use semiquantita-
tive (plus or minus a factor of 3) tech-
nicjues of sample collection and labora-
tory and field analysis: (1) to provide
preliminary emissions data for waste
streams and pollutants not adequately
characterized; (2) to identify potential
problem areas; and (3) to prioritize
waste streams and pollutants in those
streams for further, more quantitative
testing. Using the information from
Level I, available resources can be di-
rected toward Level II testing which
i nvolves specific quantitative analysis of
components of those streams that do
contain significant pollutant levels. The
data developed at Level II are used to
identify control technology needs andto
further define the environmental haz-
ards associated with emissions.
Summary
The commercial/institutional external
combustion sources evaluated in this
report are sources used for space heating
of trade establishments, health and
educational institutions, and govern-
ment facilities. These application areas
are identical to those used by the De-
partment of Energy (DOE) in compiling
energy consumption data for the com-
mercial sector. Commercial combustion
units have also been defined as units
with heat inputs ranging from 0.42 to
13.2 x 109 Joules (J)* per hour. How-
ever, this definition excludes many
smaller and larger units used in the
commercial/institutional sector. Insti-
tutional units especially tend to be
appreciably larger than 13.2* 109 J/hr
and account for almost 20 percent of the
commercial/institutional sector fuel
consumption.
Commercial/institutional fuel con-
sumption for space heating was 5.1 x
1018 J in 1978 based on DOE data for
total fuel consumption and estimates of
the fraction of this fuel used for space
heating. This consumption value is less
than 10 percent of the estimated 1978
national fuel consumption figure of 54 x
1018 J, excluding fuel used in the trans-
portation sector. Commercial/institu-
tional external combustion sources for
space heating primarily use oil (52 per-
cent) and gas (44 percent). Small amounts
of coal and wood are also used by the
commercial/institutional sector. Inter-
nal combustion sources in the commer-
cial/institutional sector, primarily gas-
and oil-fired reciprocating engines, are
used for pumping municipal water and
sewage. Small amounts of fuel may also
be used by internal combustion sources
for auxiliary power generation.
Heating systems for commercial/in-
stitutional sources are concentrated in
areas of high population density such as
the Northeast, Midwest, and parts of
California. Oil consumption is most
heavily concentrated in the Northeast
with the States of New York, Massachu-
setts, New Jersey, and Pennsylvania
consuming about 25 percent of the U.S.
total. Commercial gas consumption for
space heating is more widely distributed
than oil, but is still most heavily con-
centrated in the Midwest and Northeast.
Commercial/institutional external
combustion sources can be sold as
either packaged units or boilers to be
constructed onsite. Most units in the
commercial sector are packaged units.
Field-erected units, for the most part,
are restricted to larger institutional
facilities. Estimates of the total number
of commercial external combustion
sources have been reported and, ac-
cording to these estimates, there are
approximately 1.5 x 106 commercial
sources. Most of- the smaller units (<
13.2 x 109 J/hr) are cast iron or firetube
units, and only 5 percent of these
* 7055 Joules U) =1 Btu. Although it is EPA policy to
use the metric system, this report uses certain
nonmetric units for convenience.
smaller units are of watertube design. .
Watertube units, however, constitute'
100 percent of all units above 50 x 109
J/hr input.
Air pollution control equipment is
generally not installed on the smaller
commercial external combustion sources,
although new burner designs, atomiza-
tion methods, and furnace constructions
are being studied to reduce emissions of
NOx and particulates. Burner modula-
tion during periods of fluctuating de-
mand, instead of on/off cycling, also
reduces particulate and hydrocarbon
emissions from oil-fired sources.
Gaseous and particulate emissions
from the flue gas stacks are emphasized
in this study of commercial/institutional
combustion sources. Although some of
the larger institutional external com-
bustion systems are local sources of
water pollution and fugitive particulate
emissions from coal pile storage and
ash disposal, their contribution to the
national water pollution and fugitive
emission burden is negligible. It is
estimated, based on the amount of coal
consumed by the commercial/institu-
tional sector, that they contribute less
than 1 percent of such emissions from
all stationary combustion sources.
Evaluation of existing emissions data ,
has indicated that the data base for gas-*4
and oil-fired external combustion sources,
although limited, is adequate for nitro-
gen oxides (NOx), total hydrocarbon
(HC), carbon monoxide (CO), particulate,
and sulfur dioxide (502). However, the
existing data base for specific organic
emissions for these sources is inade-
quate and, for the oil-fired sources, the
existing data base for sulfur trioxide
(SOs) and trace elements is inadequate.
Emissions data from solid fuel-fired
sources are generally inadequate for all
pollutants.
In the case of oil-fired internal com-
bustion sources, data are inadequate for
SOa, trace element, and specific organic
emissions. Data for gas-fired recipro-
cating engines are adequate; however,
one unit was tested in this program to
confirm data adequacy.
Modified Level I sampling and analysis
procedures were used in this emissions
assessment of conventional combustion
systems program. These procedures
were developed as an integral part of
the program and were published as a
separate document. Although the pro-
cedures differ to some degree from
official EPA Level I procedures, they
have been used throughout this program A
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to ensure continuity of sampling and
analysis.
Because of the deficiencies in the
existing emissions data base, the fol-
lowing 22 external combustion systems
were tested: five gas-fired, three distil-
late oil-fired, five residual oil-fired,
three anthracite stokers, three bitumi-
nous stokers, two bituminous pulverized
dry units, and one wood-fired stoker.
Four oil-fired, one gas-fired, and one
dual-fired internal combustion recipro-
cating engines werealso tested. Specific
sites were chosen based on the repre-
sentativeness of the sites as determined
by the important system characteristics
within each source category, including
system design, size, and age. Many of
the sites tested fall within the commer-
cial size classification range, although
some, particularly the pulverized bitumi-
nous-fired units, greatly exceed the
upper commercial size limit of 13.2 *
10 J/hr input capacity.
The Source Assessment Sampling
System (SASS) train, developed under
contract to EPA, was used to collect both
gaseous and paniculate emissions in
quantities sufficient for the wide range
of analyses needed to adequately char-
acterize emissions from commercial/
institutional combustion sources. The
SASS train consists of a conventional
heated probe, three cyclones and a filter
mounted in a Heated oven, a gas condi-
tioning system, an XAD-2 polymer
adsorbent trap, and a series of impingers.
Particulate matter is size fractionated
and collected in the cyclones and on the
filter; gaseous organics and some inor-
ganics are collected by the XAD-2
adsorbent; and the remaining gaseous
inorganics and trace elements are
captured by the impingers. The train is
run until at least 30 m3 of gas have been
collected. This criterion was established
in conjunction with analytical technique
sensitivities to ensure that any emis-
sions that would increase the ambient
loading by more than 1/ug/m3 would be
detected. The cyclones were deleted for
the tests at the gas- and oil-fired sites
because paniculate loadings were too
low to provide a weighable quantity of
sample from each cyclone.
In addition to the SASS train, other
equipment was used to collect gaseous
components not captured by the train. A
gas chromatograph (GC) with a flame
ionization detector was used in the field
to analyze Ci-C8 hydrocarbons collected
.in gas sampling bags. Additionally,
fthese samples were analyzed for CO,
carbon dioxide (COz), oxygen (02), and
nitrogen (Nz) by the GC using a thermal
conductivity detector. Field sampling for
NOx and SOa was also conducted at
selected sites using a Method 7 train for
NO, (40 CFR 60, Appendix A, Method 7)
and a modified Goksoyr-Ross train for
80s collection.
A modified Level I sampling and
analytical procedure was used in this
emissions assessment program. Major
deviations from Level I Procedures were
the addition of gas chromatography/
mass spectroscopy (GC/MS) to the or-
ganic analyses, the combination of
certain SASS train fractions before
analysis, and the deletion of inorganic
analysis of SASS train samples col-
lected from gas- and oil-fired sources.
The combination and deletion guidelines
were instituted as a result of low levels
of pollutants found in the emissions of
previously tested gas- and oil-fired
utility boilers and residential heating
systems.
The Level I inorganic analysis was
designed to identify all elemental species
collected in the SASS train fractions
and to provide semiquantitative data on
the elemental distributions and total
emission factors. The primary tool for
Level I inorganic analysis is the Spark
Source Mass Spectrograph (SSMS).
SSMS data were supplemented with
Atomic Absorption Spectrometry (AAS)
data for mercury (Hg), arsenic (As), and
antimony (Sb), and with standard method
determinations for sulfates.
The following SASS train fractions
from the solid fuel-fired sources were
analyzed for their elemental composi-
tion: (1) the cyclone catches, (2) the
particulate filter, (3) the XAD-2 sorbent,
and (4) a composite sample containing
portions of the XAD-2 module conden-
sate and nitric acid rinse, and the first
impinger solution. Fuel was also ana-
lyzed for the solid fuel- and oil-fired
sources.
Level I organic analysis provides data
on volatile (C7-Ci6) and nonvolatile (>
Cie) organic compounds to supplement
data for gaseous organics (Ci-Ce) mea-
sured in the field. Organics in the
paniculate fractions, the XAD-2 sorbent,
and XAD-2 module condensate trap
were recovered by methylene chloride
extraction. SASS train components
including the tubing were carefully
rinsed with methylene chloride or meth-
ylene chloride/acetone solvent to re-
cover all organics collected in the SASS
train. SASS train rinses and extracts
recovered from the gas- and oiC-fired
sites were combined for analysis; how-
ever, samples collected from solid fuel-
fired sources were analyzed separately:
Because all samples contain signifi-
cant quantities of solvents from rinsing
and are too dilute to detect organic
compounds by most instrumental tech-
niques used by Level I procedures, the
first step in the analysis was to con-
centrate the sample fractions from as
much as 100 ml to 10 ml in a Kuderna-
Danish apparatus in which rinse solvent
was evaporated while the organics of
interest were retained. Kuderna-Danish
concentrates were then evaluated by
GC, gravimetric analysis, infrared spec-
trometry (IR), and sequential GC/MS.*
The extent of the organic analysis was
determined by the stack gas concentra-
tions found for total organics (volatile
and nonvolatile). If the total organics
indicated a stack gas concentration
below 500 fjg/m3, further analysis was
not conducted. If the concentration was
above 500 /ug/m3, a class fractionation
by liquid chromatography was conducted
followed by GC, gravimetric, and IR
analyses. Fractions that contained more
than the equivalent of 500 yug/m3 or
were of special interest were also analyzed
by low resolution mass spectroscopy
(LRMS).
The results of the field measurement
program for flue gas emissions from
commercial/institutional sources, along
with supplementary values obtained
from the existing data base for certain
pollutants, are presented in Table 1.
Also listed in this table are ambient
severity factors, defined as the ratio of
the calculated maximum ground level
concentration of the pollutant species to
the level at which a potential environ-
mental hazard exists. An ambient sever-
ity factor of greaterthan 0.05 indicates a
potential problem requiring further
attention.
The emission factors shown in Table 1
are uncontrolled emissions factors.
However, in the case of the solid fuel-
fired combustion categories, some
degree of paniculate control does exist
in the commercial/institutional sector.
Overall paniculate control efficiency is
estimated to be 40 percent for bitumi-
nous, pulverized dry bottom boilers and
20 percent for all stokers. Gas- and oil-
fired units are essentially uncontrolled.
The major modification in the Level I sampling and
analysis procedure was the GC/MS analysis for
polycyclic organic matter (POM).
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Table 1. Summary of Emissions Characterization of Commercial/Institutional Combustion Sources
Combustion source category
Gas-fired
boilers
Distillate
oil-fired
toilers
Residual
oil-tired
boilers
Bituminous,
pulverized
dry bottom
Bituminous
stokers'"
Anthracite
stokers
Wood stokers
Gas-fired
reciprocating
engines
Oil-tired
reciprocating
engines
Pollutant'
Emis- Ambient Emis- Ambient Emis- Ambient Emis- Ambient Emis- Ambient Emis- Ambient Emis- Ambient Emis- Ambient Emis- Ambient
sion sever- sion sever- sion sever- sion sever- sion sever- sion sever- sion sever- sion sever- sion sever-
factor ity factor ity factor ity factor ity factor ity factor ity factor ity factor ity factor ity
(ng/JI factor' Ing/JI factor Ing/JI Factor Ing/JI factor Ing/JI factor (ng/J) factor (ng/JI factor (ng/JI factor (ng/JI factor
Partkulates
HO,
SO,
CO
HC
Paniculate
sutlete'
SO,
Trace
elements
Al
Be
Be
Ca
Co
Cr
Co
f
fe
K
Li
Na
Ni
P
Si
V
Total POM
2
50
0.26
a
3
_
_
_
_
_
_
0.010
0.0007 6 0.0022 37
0.08 68 0.11 172
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levels were similar to those found in the
existing data base for oil-fired engines,
and ambient severity factors did not
exceed 0.05 for .any of the compounds
detected. The high POM emissions
measured for the dual-fired engine
were somewhat surprising because the
quantity of oil used represented only 5
percent of the total thermal input. No
POM emissions were detected from the
engine fired solely by gas.
Conclusions
Several conclusions, listed below,
can be drawn from this emissions
assessment of commercial/institutional
combustion sources:
Emissions of paniculate, NO* SOz,
CO, and HC from commercial/insti-
tutional sources represent approxi-
mately 1.7 percent, 4.9 percent,
3.0 percent, 0.5 percent, and 0."
percent, respectively, of total emis-
sions from stationary combustion
sources. Despite this relatively
minor contribution to national emis-
sions, criteria pollutant emissions
from individual combustion sources
can have a significant local impact
as noted below.
Flue gas emissions of N0> from all
of the commercial/institutional
source categories studied in this
program, with the exception of a
wood-fired stoker tested at low
load conditions, are of concern.
Ambient severity factors exceed
0.05 and, thus, individual sources
can have a significant local impact.
Flue gas emissions of S02from the
coal-fired and residual oil-fired
combustion sources are associated
with ambient severity factors
greater than 0.05 and, thus, are of
environmental significance. Ambi-
ent severity factors associated with
paniculate sulfate and 80s emis-
sions from the solid fuel-fired
sources tested also exceed 0.05
and are of concern.
Flue gas emissions of particulates
from uncontrolled solid fuel-fired
sources are associated with high
ambient severity factors. Moderate-
to-high efficiency control devices
are required in many cases to re-
duce severity factors to 0.05. Be-
cause the application of paniculate
control devices to solid fuel-fired
commercial/institutional combus-
tion sources is not extensive, these
sources are of practical concern.
F|ue gas emissions of total hydro-
carbon are significant for commer-
cial/institutional bituminous
stokers, wood stokers, and recip-
rocating engines. Ambient severity
factors exceed 0.05 for these com-
bustion source categories.
Flue gas emissions of CO do not
appear to be a problem. Ambient
severity factors for all source cate-
gories are 0.001 or less.
Particle size distribution data for
particulate emissions from solid
fuel-fired sources are inadequate.
Data collected in this study exhibit
large variability and contribute
little to the limited information
contained in the existing particle
size distribution data base.
Trace element emissions from un-
controlled coal-fired combustion
sources are of concern. Elements
with ambient severity factors in
excess of 0.05 include aluminum,
barium, beryllium, calcium, chlo-
rine, cobalt, chromium, copper,
fluorine, iron, potassium, lithium,
sodium, nickel, phosphorus, lead,
silicon, and vanadium. Emissions of
other elements also could be of
significance given the variability of
the elemental content of coals.
Nickel emissions form distillate oil
combustion sources, and nickel,
chlorine, chromium, and vanadium
emissions from residual oil com-
bustion sources are of concern.
Ambient severity factors for these
elements exceed 0.05.
Flue gas emission data for POM
compounds from gas- and oil-fired
commercial/institutional sites ap-
pear to be adequate. Emission
levels are generally low and the
compounds that were detected
have relatively high MATE values.
Ambient severity factors for the
compounds detected are all below
0.05.
Flue gas emission data for POM
compounds from solid fuel-fired
combustion sources are still inade-
quate. Level II techniques should
be used to study emissions from
small coal- and wood-fired com-
bustion sources. The effect of heat
input levels, on/off operating
modes, excess air levels, and other
operating parameters on POM
emissions should be studied in
more detail. If these factors are
found to contribute significantly to
POM emissions, studies to deter-
mine the prevalence of contribu-
tory source operating parameters
in the commercial/institutional
sector should be undertaken to
establish the magnitude of the
problem.
N. F. Surprenant, P. Hung. R. Li, K. T. McGregor, W. Piispanen, and S. M.
Sandberg are with GCA Corporation, Bedford, MA 01730.
Michael C. Osborne is the EPA Project Officer (see below).
The complete report, entitled "Emissions Assessment of Conventional Station-
ary Combustions Systems: Volume IV. Commercial/Institutional Combus-
tion Sources," (Order No. PB81-145187; Cost: $17.00, subject to change) will
be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Industrial Environmental Research Laboratory
U.S. Environmental Protection Agency
Research Triangle Park. A/C 27711
« U.S. aOVEBNMENT PRINTINC OFFICE 1»1 757-012/7071
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