&EPA
United States
Environmental Protection
Agency
Industrial Environmental Research
Laboratory
Research Triangle Park NC 27711
EPA-600/7-79-050d
February 1979
Proceedings of the Third
Stationary Source
Combustion Symposium;
Volume IV.
Fundamental Combustion
Research and
Environmental Assessment
Interagency
Energy/Environment
R&D Program Report
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RESEARCH REPORTING SERIES
Research reports of the Office of Research arfd Development, U.S. Environmental
Protection Agency, have been grouped into nine series These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the INTERAGENCY ENERGY-ENVIRONMENT
RESEARCH AND DEVELOPMENT series. Reports in this series result from the
effort funded under the 17-agency Federal Energy/Environment Research and
Development Program. These studies relate to EPA's mission to protect the public
health and welfare from adverse effects of pollutants associated with energy sys-
tems. The goal of the Program is to assure the rapid development of domestic
energy supplies in an environmentally-compatible manner by providing the nec-
essary environmental data and control technology. Investigations include analy-
ses of the transport of energy-related pollutants and their health and ecological
effects; assessments of, and development of, control technologies for energy
systems; and integrated assessments of a wide-range of energy-related environ-
mental issues.
EPA REVIEW NOTICE
This report has been reviewed by the participating Federal Agencies, and approved
for publication. Approval does not signify that the contents necessarily reflect
the views and policies of the Government, nor does mention of trade names or
commercial products constitute endorsement or recommendation for use.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/7-79-050d
February 1979
Proceedings of the Third
Stationary Source Combustion
Symposium;
Volume IV. Fundamental Combustion
Research and Environmental
Assessment
Joshua S. Bowen, Symposium Chairman,
and
Robert E. Hall, Symposium Vice-chairman
Environmental Protection Agency
Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, North Carolina 27711
Program Element No. EHE624
Prepared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, DC 20460
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PREFACE
These proceedings document more than 50 presentations and discussions
presented at the Third Symposium on Stationary Source Combustion held March
5-8, 1979 at the Sheraton Palace Hotel, San Francisco, California. Sponsored
by the Combustion Research Branch of the EPA's Industrial Environmental
Research Laboratory - Research Triangle Park, the symposium papers emphasized
recent results in the area of combustion modification for NOX control. In
addition, selected papers were also solicited on alternative methods for
NOX control, on environmental assessment, and on the impact of NOX control
on other pollutants.
Dr. Joshua S. Bowen, Chief, Combustion Research Branch, was Symposium
Chairman; Robert E. Hall, Combustion Research Branch, was Symposium Vice-
Chairman and Project Officer. The welcoming address was delivered by Clyde
B. Eller, Director, Enforcement Division, U.S. EPA, Region IX and the opening
Address was delivered by Dr. Norbert A. Jaworski, Deputy Director of IERL-RTP.
The symposium consisted of seven sessions:
Session I:
Session II:
Session III:
Session IV:
Session V:
Session VI:
Session VII:
Small Industrial, Commercial and Residential Systems
Robert E. Hall, Session Chairman
Utilities and Large Industrial Boilers
David G. Lachapelle, Session Chairman
Advanced Processes
6. Blair Martin, Session Chairman
Special Topics
Joshua S. Bowen, Session Chairman
Stationary Engines and Industrial Process Combustion
Systems
John H. Wasser, Session Chairman
Fundamental Combustion Research
W. Steven Lanier, Session Chairman
Environmental Assessment
Wade H. Ponder, Session Chairman
ii
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VOLUME IV
Table of Contents
Session VI: Fundamental Combustion Research
Page
"NOX Abatement in Fossil Fuel Combustion — Chemical
Kinetic Considerations," J. M. Levy, J. P. Longwell,
A. F. Sarofim ............................ 3
"Heterogeneous Processes Involved in the Control of
Nitrogen Oxide Formation in Fossil Fuel Flames,"
M. P. Heap and T. J. Tyson ..................... 45
"Transport Processes and Numerical Model Development —
FCR Program Elements," T. J. Tyson, M. P. Heap, C. J Kau
and T. L. Corley .......................... 67
Session VII: Environmental Assessment
"Survey of Projects Concerning Conventional Combustion
Environmental Assessments," W. E. Thompson ..... ........ 85
"Emissions Assessment of Conventional Combustion Systems,"
D. G. Ackerman, Jr. , J. W. Hamersma and B. J. Matthews ....... 103
"Environmental Assessment of Coal and Oil Firing in a
Controlled Industrial Boiler," K. W. Ar ledge and
C. A. Leavitt ............................ 137
"Environmental Assessment of Stationary Source
Control Technologies," H. B. Mason, E. B. Higginbotham,
R. M. Evans, K. G. Salvesen and L. R. Waterland ..... ...... 163
"An Overview of the Conventional Combustion Environmental
Assessment Program , " Deepak Kenkeremath ........... 207
iii
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SESSION VI
FUNDAMENTAL COMBUSTION RESEARCH
W. STEVEN LANIER
SESSION CHAIRMAN
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NO ABATEMENT IN FOSSIL FUEL COMBUSTION.
x
Chemical Kinetic Considerations
J.M. Levy, J.P. Longwell, A.F. Sarofim
M.I.T. Energy Laboratory and Dept. of Chemical Engineering
Cambridge, Massachusetts 02139
and
T.L. Corley, M. Heap, and T. I. Tyson
Energy and Environmental Engineering Corporation
Irvine, California 92664
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ABSTRACT
Homogeneous, gas-phase chemical reactions are of major significance in
determining NO emission levels from the combustion of condensed phase fossil
X
fuels. The approach under the E.P.A. Fundamental Combustion Research Program
to development of an NO abatement strategy through optimization of the
gas-phase reaction chemistry of nitrogenous species is summarized, and
selected applications are presented.
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SECTION 1
INTRODUCTION
The Fundamental Combustion Research (FCR) Program of the Environmental
Protection Agency is aimed at the establishment of strategies for reducing
NOY production through combustion process modification. Complete character-
A
ization of the factors affecting NO production must, by nature of the
combustion process itself, include consideration of such diverse processes
as homogeneous gas phase reactions, heterogeneous gas-solid reactions, heat
transfer, and aerodynamics. We report here on current progress under the
FCR program in the elucidation of the homogeneous gas-phase chemical kinetic
mechanism of NO formation in fossil-fuel combustion.
A
The strategy adopted in the FCR program is discussed in this manuscript.
Illustrations of selected results will be presented and updated at the
"Third Symposium on Stationary Source Combustion".
With the depletion of natural gas and petroleum reserves (which are
lacking or low in nitrogen content - and, hence, relatively low in the
emission of NO formed from the nitrogen bound in the fuel), and the
X
increasing substitution of coal, coal-derived liquids, residual fuel-oils,
and shale oils (which are high in nitrogen content), NOX emissions, which are
already unacceptably high in several urban areas, are bound to increase
unless an abatement strategy is developed and implemented. Insofar as the
mechanism by which fuel-bound nitrogen is converted to NO is complex, and
12
insofar as early attempts ' to reduce NO emissions by empirical adjustment
X
of combustion parameters (e.g., temperature, fuel/air ratio, degree of
mixedness, etc.) utilizing conventional combustors have achieved only a
fraction of their full potential, a more fundamental elucidation of the N0x
formation mechanism has become essential in order to achieve the desired
engineering goal of modifying the combustion process in such a way as to
favor the conversion of fuel-bound nitrogen to the desired (combustion) end
-------
product, N™, rather than to the undesired product, NO.
As such, the organization of the FCR program has defined the following
approach to achieving this end:
a) Identification of chemical reaction sets with an emphasis
on fuel nitrogen conversion,
b) Validation of these reaction sets by modeling a wide range
of pertinent experimental results, and concommitant computational
screening to identify the minimum reaction subsets adequate for
prediction of NO emission levels,
X
c) Through these processes, identification of critical gaps in
the existing data base necessary for prediction of NO levels,
X
and d) Application of the fuel-N reaction set to the computation
of NO emission levels from systems of practical interest, and
X.
utilization of predictive capabilities for development of NO
X
abatement strategies.
In order to clarify the results, initial chemical kinetic studies have
concentrated on aerodynamically clean systems in which interpretation of
results are not complicated by mixing effects. A parallel effort under the
FCR program is the characterization of the aerodynamics and development of
methodologies for coupling the kinetics with the flow field in real,
aerodynamically complex combustors.
SECTION 2
THE IMPORTANCE OF GAS-PHASE KINETICS
Essential to the development of a combustion modification strategy which
minimizes N0x emissions is a thorough understanding of the gas phase chemistry
by which fuel-bound nitrogen is converted to NOV. This is easily understood
X
by reference to Figure 1 which schematically denotes several of the chemical
processes involved in the combustion of coal or residual fuel oil. Indeed,
it is well understood that for any condensed phase fuel, combustion may
proceed through parallel homogeneous and heterogeneous processes wherein the
fuel is initially heated and undergoes devolatilization followed by rapid
homogeneous gas phase oxidation of the volatile species and, if a devolatil-
ized residue remains, slower heterogeneous burnout of the char. This is
apparently the case for the combustion of pulverized coal and residual fuel
-------
oils. Distillate oils, however, may well burn entirely in the gas phase as
a diffusion flame surrounding a shrinking, evaporating droplet. Certain
fuels, of course, are gaseous from the outset.
Of primary interest here, however, is the chemistry of volatile fuel-
nitrogen conversion. Traditional gaseous fuels (natural gas) contain little
or no bound nitrogen - although it is projected that the products of coal
gasification which undergo a high temperature desulfurization may well contain
significant quantities of ammonia. In addition, light distillate oils which
for coal and shale-derived fuels may have nitrogen contents in excess of 1%
by weight burn entirely in the volatile phase.
For fuels which leave a devolatilized residue, the relative significance
of gas phase (versus heterogeneous)processes on NOX formation is less obvious.
The distribution of nitrogeneous species between volatiles and char has
recently been studied '.' for pulverized coal combustion for temperatures
ranging from 1250 to 1750°K. The results (for a Montana Lignite) shown in
Figure 2 clearly demonstrate that at higher temperatures under fuel lean
conditions, as much as 80% of the NO formed may originate in the volatile
X
phase. This reflects the fact that at high enough temperatures, nearly all
3
of the nitrogen in coal can be driven into the gas phase . One may, however,
make an observation, based upon Figure 2 which renders an understanding of
the gas phase chemistry all the more vital - namely, that even under
conditions (1750°K) where 70% or more of the fuel nitrogen is volatilized
during the course of the experiment , for equivalence ratios above about 1.5,
over 50% of the NO originates from the char! These results reflect the long
x 8
established facts that increases in fuel nitrogen concentration and
Q Q 1 Q
equivalence ratio *' in the gas phase all tend to lower^ the conversion
efficiency to NO . The strategy for controlling N0x emission is to drive as
much fuel nitrogen as possible into the gas phase in a primary fuel rich zone
where the reaction kinetics can be "engineered" to minimize conversion to NOX,
as opposed to the alternative of allowing the nitrogen to remain in the char
where subsequently it will be partially converted to N0x in the fuel lean
secondary combustion zone . Clearly, optimizing this reaction engineering
(minimizing NOX emissions) is best achieved through a true understanding of
the gas phase reaction mechanism.
-------
Unfortunately, similar, detailed data pertinent to residual fuel oils
(petroleum, shale, or coal derived) are currently lacking. Current EPA
sponsored studies should shortly yield phenomenological data on the influence
of combustion conditions on the pathways (including volatile/char fraction-
ation) followed by fuel-bound nitrogen for these systems of interest. One
might speculate, however, at this time that these fuels may well behave
similarly to pulverized coal, and that, in any event, an NO abatement
X
strategy is likely to rest heavily, if not entirely, upon control of the
reactive chemistry of the volatile, nitrogeneous species.
SECTION III
ESTABLISHMENT OF A KINETIC MECHANISM FOR NOx FORMATION
AND DESTRUCTION FROM FUEL-BOUND NITROGEN.
As indicated above, development of an NOX control strategy rests heavily
upon optimizing the conversion of volatile fuel-nitrogen species to N2>
Insofar as the residence times in typical combustors are far too short to
achieve chemical equilibrium in the burnt gases, it is necessary to consider
the time dependent flow of nitrogenous species through the many sequential
and competing reaction pathways leading to NO and No formation, in order
X ^
to develop a methodology for maximizing or minimizing certain product yields
- i.e., both the elementary reaction pathways and reaction rates must be
considered.
Although at this time, many details of the NO formation and destruction
X 8 12
mechanism are not fully understood, a considerable literature * has
appeared in recent years, in which the predominant nitrogenous species
appearing as intermediates or products of fuel-nitrogen conversion have been
identified, and from which a rough reaction mechanism ' ' may be deduced.
Having identified an adequate species set, a "complete" reaction
mechanism has been constructed by permitting all species to inter-react
via elementary reactions. Rate constants were selected from a search of the
experimental literature, where available, or from tabulated estimates (made,
generally, by the method of Johnston ). The fuel-nitrogen reaction set is
shown in Table 1. Conspicuously absent are several reactions, for example,
NH(NH2) + NO -»• N2 + OH(H20), often invoked in NO mechanisms. Although of
8
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questionable "elementary" nature, for completeness, they have been included
in modelling efforts.
Current efforts under the FCR program are directed to extending the
kinetic mechanisms to higher hydrocarbons. Unfortunately, there is a dearth
of elementary mechanistic and rate data for hydrocarbons representative of
27
petroleum, coal, or shale derived fuels. Global modelling of hydrocarbon
combustion (by either finite or infinite rate formation of CO and 1^), has
proven to be useful for purposes of estimation of heat release rates, but
28
may seriously mis-predict intermediate free radical levels which are
crucial to the proper computation of NO emissions, particularly under fuel
X 29
rich conditions. Current semi-global developments are more promising in
that they include some higher intermediates between the initial hydrocarbon
and CO. The approach under development is the extension of the semi-global
30
method based upon the observation that several relatively small hydrocarbon
species appear as (pyrolysis) intermediates in the combustion of higher
hydrocarbons. The initial species set under consideration includes C^^
( a major intermediate of aromatic systems), C»H,, CH,, and CO/H«. The
31
combustion mechanisms of C2H~ and C-H, have been recently studied and are
under continuing investigation.
SECTION 4
VERIFICATION OF THE REACTION MECHANISM
SELECTION OF FUEL SYSTEMS
It is intuitively clear that the chemistry of NOX formation is intimately
coupled to the chemistry of the combustion of the parent fuel. This is
readily understood through the simple observation that N0x levels are strongly
influenced by the concentration/time history of active free radicals (H,0,OH)
which are, themselves, strongly determined by the combustion details of the
fuel. Clearly, establishment of an adequate fuel-nitrogen reaction mechanism
requires modelling of experiments utilizing the simplest fuels whose combus-
tion mechanisms are already well understood.
In this regard, the two best characterized fuel systems are ^^2 and
O. However, insofar as additional mechanistic complexities pertinent
-------
to NO formation levels arise in the presence of hydrocarbon fuels (namely,
X
reactions between nitrogenous species and hydrocarbon fragments), it has been
necessary, also, to consider the simplest hydrocarbon, methane, as a model
fuel, with the H« and CO reaction mechanisms logically appearing as subsets
of the methane reactions set. Insofar as, at the time of initiation of these
studies, no adequately validated methane reaction set was available, it has
proven necessary, in parallel with considerations of fuel-nitrogen reactions,
to develop and verify a methane mechanism.
The methane/fuel-nitrogen reaction set used in these studies has been
developed at Energy and Environmental Research (EER) as a continuation of
Engleman's recent EPA compilation of CH, reaction data. The method employed
by Engleman and continued under the FCR program has been to assemble a species
set, consider all possible reactions among species of the set, and, having
made a best judged assignment of rate coefficients, to computationally screen
out all reactions and species whose influence on computed results is
18
insignificant. By this method the screened set appearing in Table 2 was
constructed. This is the set successfully used by EER in their NOx modelling
results summarized below, and, contained in this set are reaction subsets
which, used with unaltered rates constants, have proven successful
in modelling NO levels in H9 and in CO/H» systems.
X £* £*
It is recognized, in the light of recent experimental and computational
19 20 21
results ' ' that methane combustion produces C- and higher hydrocarbon
species not included in this set. The successes achieved with the EER set
in modelling NO levels, temperatures, and residual oxygen levels suggest
X
that exclusion of higher hydrocarbons from the methane set is justifiable
for the systems modelled. The conditions under which the higher hydrocarbons
need to be included are being investigated.
In any case, the success achieved in modelling stirred reactor
experiments for three reasonably if not perfectly characterized fuels lends
credance to the adequacy of the fuel-nitrogen reaction set included in Table 2,
and suggests its applicability for modelling NO formation levels when
included in a reaction scheme for higher hydrocarbon fuels. A continuing
activity under the FCR program is to compare the screened set of reactions
for the methane/fuel nitrogen mixtures shown in Table 2 with more complete
sets that become available. For example, the inclusion of the additional
10
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reactions in Table 1 into the EER set is found to yield only negligibly small
differences in computed NOX levels.
The testing of the reaction set has been constrained by the availability
of data on fuel nitrogen conversion taken under sufficiently well defined
conditions to provide a critical assessment of the proposed mechanism and
rate constants. Part of the FCR program is aimed at providing data on well-
stirred and plug flow reactors which can be used for model validation.
MODELLING RESULTS OF THE FCR PROGRAM
The reaction set of Table 2 has been used at EER to model a variety of
experimental results on CH,, CO, and H2 systems. These include stirred
reactor experiments, flat flame experiments, and shock tube experiments.
Selected examples of modelling results are presented here, a comprehensive
O O
review being available elsewhere . It is to be stressed that all modelling
results utilize the identical reaction set (or subset) with no adjustment of
rate parameters. Numerical integration of the coupled rate equations is
achieved utilizing a computer code developed at EER according to the method
23
of Tyson .
Initial validation of the reaction set was accomplished through modelling
of the experiments of Bartok and Engleman for NO formation in a Longwell
jet-stirred reactor. These data included CH^/air mixtures with and without
the addition of fuel-nitrogen in the form of NO or NH3 to the inlet stream,
and CO/H2/air and H2/air mixtures without added fuel nitrogen. Nitric oxide
emission levels and reactor temperature were the primary variables used to
verify the kinetic model. Residual oxygen levels were also used as a check
when the data were available. Results of similar calculations using a
9fi
preliminary reaction set have been presented previously . Modelling results
using the reaction set of Table 2 are shown in Figure 3 for the production
of thermal NO and in Figure 4 for conversion of fuel-nitrogen (1300 ppm NH3
in the inlet mixture) to NO in an atmospheric pressure stirred reactor
experiment with a 2 msec mean residence time, a specified heat loss of
36.1 cal/gm, and an inlet temperature of 464°K. Additional calculations have
established the relative contributions of each reaction pathway to production
or destruction of species in the reaction set. The sensitivity of computed
results to changes in the values of individual rate constants have also
been established computationally.
11
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A generalized computer code for the calculation of diffusion flame
behavior has been developed at EER. One natural limit-case of this code is
the flat flame. This option has been utilized at EER to model several flat
flame experiments as shown in Table 3. Modelling of a methane/air flat flame
is shown in Figures 5-7. SECTIONS
APPLICATIONS TO MODELLING REAL COMBUSTION SYSTEMS
Parametric or phenomenological studies of fuel-nitrogen conversion (See
Figure 2, for example) have suggested staged combustion as a method of
reducing N0x emissions from volatilized fuel nitrogen species. For coal, the
rational is to operate the first stage at high temperatures (where fuel-
iiitrogen volatilization is maximized), fuel-rich (where volatile fuel-nitrogen
conversion to NO is minimized) and to operate the second stage at low
X
temperature (where the fixation of atmospheric N« via the Zeldovich mechanism
to form "thermal" NO is minimized), fuel-lean (to complete fuel burnout).
As a result of the lean second stage conditions, however, any form of bound
nitrogen (other than N~) such as cyanides or amines which exit the first stage
will be partially converted to NO. Thus, minimization of NO emissions
X
actually entails minimization of total bound nitrogen emission from the first
stage. (In the absence of staging, this would, in any case, be desirable as
HCN and NH- would be considered undesirable emission products). The degrees
of freedom available to the combustion engineer are many, including the
temperature, air/fuel ratio, and residence time in the fuel-rich stages and
the rates of air addition to and heat removal from the partially burned
primary combustion products.
The utility of a validated mechanism such as that of Table 2 is to
provide a method for systematically evaluating the effect of different
process variables. An example is given in Figure 8 in which the decay of
total bound nitrogen in a plug flow section is shown for ammonia-doped
methane/air combustion as a function of flame temperature. Such quantitative
data are of great pertinence to design considerations - such as first-stage
residence time or size - if NO emissions are to be kept below appropriate
X
emission standards.
The results of Figure 8 are also valuable as a baseline case about which
an optimization strategy for minimizing NO emissions is being developed.
X
12
-------
Existing modelling capabilities are being applied to determine an optimum
mode for coupling the rich primary zone with the lean secondary zone. As
26
indicated earlier , several methods of adding secondary dilution air may be
considered, varying from "instantaneous" mixing of all the secondary air with
the primary products at the entrance to the secondary region, to gradual
mixing of the secondary air over the full residence time in the secondary
stage, or even, conversely, gradual mixing of the primary products into the
secondary dilution air. Chemical kinetic computations predict widely
differing NO emission levels for different staging configurations and
X
suggest that the decay of bound-nitrogen species can be accelerated by the
addition of secondary air in a series of stages. The model can be used to
determine the maximum NOX control achievable by aerodynamic staging.
Kinetic calculations utilizing the simplified methane reaction set
(Table 2) have also shown the important role played by hydrocarbon fragments
in determining NOX emissions from a fuel-rich primary zone. It is
demonstrable in methane/air systems under conditions of staged combustion
hydrocarbon persistence enhances NOX emissions, largely through HCN forming
reactions between hydrocarbon fragments and nitrogen-bearing molecules, as
well as through hydrocarbon competition for the active free radicals which
destroy HCN. The implication is, therefore, that NOX minimization is aided
through first stage design which maximized hydrocarbon depletion. In this
regard, it is of great importance to extend quantitative kinetic modelling
capabilities to higher hydrocarbon systems.
SECTION VI
CONCLUSIONS
Gas-phase chemical kinetic modelling under the EPA FCR program has
achieved several milestones necessary for the development of a practical
strategy for minimization of NO emissions from fossil-fuel combustion.
Program goals and their current status may be summarized as follows:
1. Development of pertinent reaction sets for fuel-nitrogen
reactions and for methane combustion. The fuel-nitrogen set is
reasonably complete, although the influence of C^ and higher
13
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hydrocarbon-species on bound-nitrogen levels in methane combustion
remains to be assessed.
2. Validation of these reaction sets through modelling of stirred
reactor experiments. In this regard, the reaction set of Table 2
adequately predicts existing stirred reactor data with some fall-off
in accuracy under fuel-lean and fuel-rich extremes. Extension of
these experiments under the FCR program is expected to provide more
extensive data, including HCN and NH_ concentrations, allowing for
more stringent reaction set validation.
3. Extension of modelling capabilities to more complex experimental
configurations, including several flame types. The computer code
has been developed and is available for critical testing of reaction
models against well-characterized data.
4. Application of the methane reaction set (Table 2) to identification
of the chemical processes of primary importance for NOX formation and
destruction in a stirred reactor. Assessment of the roll of higher
hydrocarbons remains under consideration.
5. Extension of computational capabilities to include fuel-nitrogen
conversion in hydrocarbon fuels more representative of fuels of practical
interest. A potential semi-global method has been identified, the
applicability of which is under current examination.
6. Development of staging methodologies for minimization of NO
X
emissions. Consideration of bound-nitrogen decay rates computed in
plug-flow utilizing the simplified methane reaction set of Table 2
suggest several concepts pertinent to optimum staging. For example,
hydrocarbon persistence is shown to retard HCN decay. Extension of
modelling capabilities to more complex fuels is necessary in order
to generalize kinetic considerations pertinent to optimization of a
staging configuration.
14
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REFERENCES
la. Turner, D.W., and C.W. Siegmund, "Staged Combustion and Flue Gas Recycle:
Potential for Minimizing NOX from Fuel Oil Combustion", American Flames
Research Committee Flame Days, Chicago, September, 1972.
b. Turner, D.W., R.L. Andrews, and C.W. Siegmund, "Influence of Combustion
Modifications and Fuel Nitrogen Content on Nitrogen Oxide Emissions from
Fuel Oil Combustion", AIChE Symposium Series 68, 55 (1972).
c. Siegmund, C.W. and D.W. Turner, "NOX Emissions from Industrial Boilers:
Potential Control Methods". J. Eng. Power, p.1-6, January, 1974.
2a. Bartok, W., A.R. Crawford, and G.J. Piegari, "Systematic Field Study of
NOX Emission Control Methods for Utility Boilers", Esso Research and
Engineering Co., Report No. GRU. 4GNOS.71 to the Office of Air Programs,
Research Triangle Park, North Carolina, December 1971.
b. Martin, G.B. and E.E. Berkau, "An Investigation of the Conversion of
Various Fuel-Nitrogen Compounds to Nitrogen Oxides in Oil Combustion",
AIChE Symp. Ser. 68, 126, 45 (1972).
c. Heap, M.P., T.M. Lowes, R. Walmsley, and H. Bartelds, Burner Design
Principles for Minimum NOX Emissions, Proceedings Coal Combustion Seminar,
Research Triangle Park, N.C., EPA Report No. EPA 650/2-73-021, Sept. 1973.
3. Pohl, J.H., "Fate of Fuel Nitrogen", Sc.D. Thesis, M.I.T. (1976).
4. Pohl, J.H. and A.F. Sarofim, "Devolatilization and Oxidation of Coal
Nitrogen", Sixteenth Symposium (International) on Combustion, The
Combustion Institute, p. 491, Pittsburgh (1977).
5. Song, Y.H., "Fate of Fuel Nitrogen During Pulverized Coal Combustion",
Sc.D. Thesis, M.I.T. (1978).
6. Song,Y.H., Beer, J.M., and Sarofim, A.F., "Fate of Fuel Nitrogen During
Pyrolysis and Oxidation", Second Annual Symposium on Stationary Source
Combustion, New Orleans, LA (1977).
7. Levy, J.M., J.H. Pohl, A.F. Sarofim, and Y.H. Song, "The Fate of Fuel-
Nitrogen Under Conditions of Pulverized Coal Combustion", Final Report to
EPA, Grant Number R803242 (1978).
8. Fenimore, C.P., "Formation of Nitric Oxide from Fuel Nitrogen in Ethylene
Flames", Comb, and Flame, 19^ 289 (1972).
9a. DeSoete, G.G., "Le Mecanisme de Formation D'Oxyde Azotique a Partir
D'Ammoniac et D'Amines Dans Les Flammes D'Hydrocarbures", Revue de
L1Institute Francais Du Petrole 28, 95 (1973).
15
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9b. DeSoete, G.G. and A. Queraud, "Formation D'Oxyde DfAzote Dans Les Flammes:
Formation D'Oxyde D'Azote A Partir De L'Azote Du Combustible. C-Addition
de NO Dans Les Melanges Inflammables. Report No. I.F.P. n° 21.681,
Institute Francais Du Petrole, Rueil Malmaison. France (1973).
10. Sarofim, A.F., G.C. Williams, M. Modell, and S.M. Slater, "Conversion of
Fuel Nitrogen to Nitric Oxide in Premixed and Diffusion Flames". AIChE
Symposium Series 148, Volume 71 51 (1975).
11. See, also, Pershing, D.W. and J.O.L. Wendt, "Pulverized Coal Combustion:
The Influence of Flame Temperature and Coal Composition on Thermal and
Fuel NOx", Sixteenth Symposium (International) on Combustion, The
Combustion Institute, p. 389, Pittsburgh (1977).
12. Recent Examples Include;
a. Fenimore, C.P., "Reactions of Fuel-Nitrogen in Rich Flame Gases",
Comb.and Flame, 26_, 249 (1976).
b. Morley, C., "The Formation and Destruction of Hydrogen Cyanide from
Atmospheric and Fuel-Nitrogen in Rich Atmospheric-Pressure Flames",
Comb, and Flame, 27_, 189 (1976).
c. Haynes, B.S., "Reactions of Ammonia and Nitric Oxide in the Burnt Gases
of Fuel-Rich Hydrocarbon-Air Flames", Comb, and Flame 28, 81 (1977).
d. Haynes, B.S., "The Oxidation of Hydrogen Cyanide in Fuel-Rich Flames",
Comb, and Flame, 28^ 113 (1977).
13. Sarofim, A.F., J.H. Pohl, and B.R. Taylor, "Strategies for Controlling
Nitrogen Oxide Emissions During Combustion of Nitrogen Bearing Fuels",
AIChE 69th Annual Meeting, Chicago, (1976).
14. Haynes, B.S.. "Kinetics of Nitrogen Oxide Formation in Combustion", in
Progress in Astronautics and Aeronautics, Volume 62 (C.T. Bowman and
J. Birkeland, eds.), Alternative Hydrocarbon Fuels: Combustion and
Chemical Kinetics , American Institute of Aeronautics and Astronautics
(1978).
15. Levy, J.M., J.P. Longwell, and A.F. Sarofim, "Conversion of Fuel-Nitrogen
to Nitrogen Oxides in Fossil Fuel Combustion: Mechanistic Considerations,"
report to Energy and Environmental Research Corp. by the M.I.T. Energy
Laboratory, EPA FCR program (1978).
16a.Mayer, S.W., L. Schieler, and H.S. Johnston, "Computation of High-
Temperature Rate Constants for Bimolecular Reactions of Combustion
Products", Eleventh Symposium (International) on Combustion, The
Combustion Institute, p. 837, Pittsburgh (1966).
blunder, R., S. Mayer, E. Cook, and L. Schieler, Aerospace Corportation
Report TR-1001 (9210-02)-! (1967).
17. Engleman, V.S., "Survey and Evaluation of Kinetic Data on Reactions in
Methane/Air Combustion", U.S. E.P.A. Report, EPA-600/2-76-003 (1976).
18. Corley, T., Energy and Environmental Research Corp., Santa Ana, CA.
unpublished data (1977).
19a.Dryer, F.L. and !„ Classman, "High Temperature Oxidation of CO and CH^",
Fourteenth Symposium (International) on Combustion, The Combustion
Institute, p.987, Pittsburgh (1972).
16
-------
b. Westbrook, C.K., J. Creighton, C. Lund, and F.L, Dryer, "A Numerical
Model of Chemical Kinetics of Combustion in a Turbulent Flow Reactor",
J. Phys. Chem. 81, 2542 (1977).
20a. Gardiner, Jr., W.C., et al., "Rate and Mechanism of Methane Pyrolysis
from 2000° to 2700°K", Fifteenth Symposium (International) on
Combustion, The Combustion Institute, Pittsburgh (1974).
b. Olson, D.B. and W.C. Gardiner, Jr., "Combustion of Methane in Fuel-Rich
Mixtures", Comb, and Flame 32., 151 (1978).
21. Harvey, R. and A. MacColl, "The Formation of C2 Hydrocarbons within
Methane Oxygen Flames", Seventeenth Symposium (International) on
Combustion, The Combustion Institute, Leeds, England (1978).
22. EER Report to EPA, W.S. Lariier, EPA Project Officer (1978).
23. Tyson, T.J., "An Implicit Integration Method for Chemical Kinetics",
TRW Report No. 9840-6002 RUOO, September (1964).
24. Bartok, W., V.S. Engleman, and E.G. Del Valle, "Laboratory Studies and
Mathematical Modelling of NO Formation in Combustion Processes",
Exxon Research and Engineering Company Report No. GRU-3GNOS-71, EPA No..
APTD 1168, NTIS No. PB 211-480 (1972).
25a. Engleman, V.S.. W. Bartok, J.P. Longwell, R.B. Edelman, "Fourteenth
Symposium (International) on Combustion", The Combustion Institute,
p. 755 (1973).
b. Engleman, V.S./'Mechanism and Kinetics of the Formation of NOX and Other
Combustion Pollutants: Phase I, Unmodified Combustion", EPA-600/7-76-009a
(1976).
26. Heap, M., T.J. Tyson, J.E. Cichanowicz, R. Gershman, R., C.J. Kau,
G.B. Martin, and W.S. Lanier, "Environmental Aspects of Low BTU Gas
Combustion", Sixteenth Symposium (International) on Combustion, The
Combustion Institute, p. 535 (1977).
27a. Edelman, R.B. and O.F. Fortune, "A Quasi-Global Chemical Kinetic Model
for the Finite Rate Combustion of Hydrocarbon Fuels With Application
to Turbulent Burning and Mixing in Hypersonic Engines and Nozzle",
AIAA Paper No. 69-86 (1969).
b. Mellor, A.M., "Current Kinetic Modelling Techniques for Continuous
Flow Combustors", in Emissions from Continuous Combus_tion Systems,
(Cornelius, W. and Agnew W.G., Eds.) Plenum Press (1972).
28. Bowman, C.T. and A.S. Kesten, "Kinetic Modelling of Nitric Oxide
Formation in Combustion Processes", Fall Meeting, Western States Section,
The Combustion Institute, Paper No. 71-28, Irvine, CA (October 1971).
29. Dryer, F.L. and I. Classman, "Combustion Chemistry of Chain Hydrocarbons"
in Progress in Astronautics and Aeronautics, Volume 62 (Bowman, C.T.
and J. Birkeland, eds.), Alternative Hydrocarbon Fuels: Combustion and
Chemical Kinetics, American Institute of Aeronautics and Astronautics
(1978).
30. See, For Example,
a. Orr, C.R., "Combustion of Hydrocarbons Behind a Shock Wave", Ninth
17
-------
Symposium (International) on Combustion, The Combustion Institute, Pittsburgh
(1963).
b.Fujii, N. and T. Asaba, "Shock Tube Study of the Reaction of Rich Mixtures
of Benzene and Oxygen", Fourteenth Symposium (International) on Combustion,
The Combustion Institute, Pittsburgh (1972).
c.Bittner, J.D. and J.B. Howard, "Role of Aromatics in Soot Formation", in
Progress in Astronautics and Aeronautics, Volume 62 (Bowman, C.T. and
J. Birkeland, Eds.) Alternative Hydrocarbon Puelg: Combustion and Chemical
Kinetics. American Institute of Aeronautics and Astronautics (1978);
and references therein,,
31.Jachimowski, C.J., "An Experimental and Analytical Study of Acetylene and
Ethylene Oxidation Behind Shock Waves", Comb, and Flame 29. 55 (1977).
18
-------
Product
Secondary
Pyrolysis
Process
Primary
Pyrolysis
Gas Phase
Oxidation
Heterogeneous
Oxidation
Figure 1. Schematic of Processes Occuring During the Formation of Nitric Oxide From Coal Nitrogen.
An Oxidative Pyrolysis Route is not Shown.
-------
•o
V
£ fli
O w
O JJ^
-| i
o ,*
T3
(V
t
O)
O)
O
-M
90
80
70
60
50
40
30
20
10
90
80
70
60
50
40
30
20
10
xx
L
1 2
Fuel/Oxygen Equivalence Ratio
Figure 2. Fate of Volatile Nigrogen During Oxidation: Total Nitric Oxide Contributed
by Volatiles (Top); Conversion Efficiency of Volatiles to Nitric Oxide (Bottom).
20
-------
110
90
70
Q.
Q.
o 50
30 -
10 -
A Engleman et al (1973)
O Engleman (19765)
• Prediction
O
O -
I
I
I
60
80 100 120
% Theoretical Air
140
Figure 3. NO Formation for CH.-air in a Well-stirred Reactor: Predicted
and Measured.
-------
,90
o
o
Conversion NhU
• •
«! ^
0 O
1—
(O
o
'5 «30
to
u.
olO
1 1 1 1
A Bartok et al (1972)
~ • Prediction
• T
• T J_
A
^ T J-
^T A
•*^
T
A
J_
1 1 1 l
60 80 100 120
% Theoretical Air
Figure 4. WU Conversion for DL-air in a Well-stirred Reactor:
Predicted and Measured.
22
-------
0.1
10
-1
c
o
O
IO
0)
"o
io"2
10 J
CO,
CH4/02 Flat Flame
(0.095/0.905)
p = 0053 atm
Flame Velocity = 67 cm/sec
Predicted
0.1
0,3
0.5
007
X cm
Figure 5.
23
-------
1.0
CO
10'
,-3
10'
,-4
Peeters & Hahnen
CH4/02 (0.095/0.905)
p » 0.053 atw
Predicted Vf • 76.2 cm/sec
Predicted
JL
_L
2000
1500
1000
500
0.1
0.3
0.5
0.7
•> __—»•—at
-*t-*
Predicted
Experimental Data
CH4/0? (0.095/0.905)
P = 0.053 atm
Predicted Vf = 76.2 cm/sec
(cm)
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
X (cm)
Figure 6.
Figure 7.
-------
I I I I I I I I I
I I I I I I I I I I
CH4 + Air/1% NH3
1 msec WSR * PFR
* = 1.33
16 32 45 64 80 96 112 128
Plug Flow Time (msec)
144
1600°K
^«»V 2200°K
v*«* ""
**
\ —
I I I 1 I I I I I I I I I I I I I I I I
160
Figure 8.
-------
Table 1. Fuel-Nitrogen Mechanism
Reaction
1.
2.
3-
H.
5.
6.
7.
8.
9-
10.
11.
12.
13.
1«.
15-
16.
17.
NO + OH = N + H02
N+N+M=N2+M
NH + NH = N + NH2
N + NH3 = NH + NH2
N + N02 = NO + NO
N + N20 = N2 + NO
N+H + M=NH + M
NH + H = N + H2
NH + 0 = NO + H
NH + 0 = N + OH
NH + OH = N + H20
N + H02 = NH + 02
NH + N ~ N2 + H
NH + N02 = HNO + NO
NH + 0 + M = HNO + M
NH2 + H = NH + H2
NH? + 0 = NH + OH
}
A(
2.
3-
3.
2.
3.
5.
2.
6.
1.
6.
5.
3.
1.
5.
1.
1 1.
6.
2.
1.
1.
9.
cm
AT
Nexp
^\
mole sec'
1
x
02
6
1
6
0
5
3
0
3
0
16
0
0
6
0
3
0
0
*
2
X
X
X
X
X
X
X
X
X
1011
X 1
10
10
10
r\
11
11
12
108
10
10
10
10
10
17
J- r
11
12
11
11
x 1011
X
X
X
X
X
X
X
X
X
1012
10
10
10
10
10
11
12
11
11
11
{-E/RT}
N
0.
0.
0.
0
0
-0
0.
0.
0.
0.
0.
0.
0.
0.
0
0.
0.
5
0
55
5
.5
5
68
5
5
5
5
5
56
5
5
1016 -0.5
1011
10
11
0.
0.
67
5
E(cal/mole) References
76,800
-990
1900
23,160
0
10,000
0
8000
1800
0
5000
8000
100
2000
1500
0
0
5000
0
4300
0
1, *
2
l 1} ^ * -
J-,^ » j t , '
1,*
3
3,6,*
3
3,7, *,D
1 4 8 9 * D
3,7,-P
1,9,*,D
3,7,*,D
1,8,*,D
3,10,*,D
1,4,8,*,D
3,11
3,7,*
3,10,*
3,10,*
1,9,12,*
1,9,12,*
26
-------
Table 1. Fuel-Nitrogen Mechanism (con't)
Reaction
18.
NH2 + 0 = HNO + H
A(
2.
. cm'
3
•\
• mole see'
1 x
io12
>5 x 1012
19-
20.
21.
22.
23.
21.
25.
26.
27.
28.
29-
30.
31-
32.
33-
3l»
35.
36.
37.
38.
39.
NH2 + OH =
NH + NH =
^ *-
NH, + O, =
NH3 + H = 1
NH3 + 0 =
NH, + OH =
3
NH3 + 02 =
N 4- NO = N
N20 + M =
N00 + OH =
2
N20 + NO =
NO + M = N
NO + H = N
NO + 0 = N
N02 + H =
N02 + 0 =
NO + H02 =
NO + H02 =
HNO + NH =
NH3 + NO =
NO + H + M
NH + H20
= NH + NH~
j
NH + H02
»H2 + H,
NH2 + OH
NH0 + H-0
2 2
NH2 + H02
2 + 0
N2 + 0 + M
N- + HO.,
2 2
N2 + N02
+ 0 + M
+ OH
+ o2
NO + OH
NO + 02
HNO + 02
N02 + OH
NO + NH2
HNO + NH2
I = HNO + M
3.
1.
1.
1.
1.
1.
5.
3-
1.
3
2
1
2
1
3
1
7
1
2
5
5
0 x
7 x
0 x
9 x
5 x
0 x
0 x
,1 x
io10
io11
IO13
io11
io12
io10
io11
IO13
.12 x 1014
.16
.0 x
.11
.22
.72
.16
.0 x
.2 x
.0 x
.0 x
x IO13
1 U
io14
x IO21
1 U
x lO1^
xlO9
i ii
x lO1^
1 3
IO13
IO10
1 7
IO13
io11
.0 x 101"
.37
xlO15
N
0
0
0.68
0.63
0
0.67
0
0.68
0.5
0
0
0
0
-1.5
0
1
0
0
0.5
0
0.5
0
0
E(cal/mole) References
0
0
1300
3600
50,500
3400
6000
1100
56,000
331
51,280
15,000
50,000
153,000
50,500
38,610
1500
1000
10,800
3000
2000
50,000
-600
13
11
1,9,12,*
1,12,*
15,*
1,9,12,*
2,1
1,9,12,*
15,*
2
16
3,*
3
2
17
18
3,2
3,2
1,*
3
1,9,*
17,*
2
27
-------
Table 1. Fuel Nitrogen Mechanism (cpn't)
Reaction
10.
11.
12.
13-
11.
15.
16.
17.
18.
19.
50.
51.
52.
53.
51.
55.
56.
57.
58.
59.
60.
61.
62.
63.
HNO
N02
N20
N20
N20
2
N20
HNO
HNO
HNO
HNO
HNO
HNO
HNO
+ 0 =
+ N =
+ H =
+ H =
+ 0 =
•f 0 =
+ NH '
+ H =
+ H =
+ 0 =
+ 0 =
+ OH
+ N =
+ N =
NO,
N.O
NH +
N, +
NO +
N2 +
= HNO
H2 +
NH +
NH +
+ H
+ 0
NO
OH
NO
°2
+ N2
NO
OH
°2
NO + OH
= NO
NH +
NpO
+ H20
NO
+ H
NH + H + M = NH2 + M
NH3
N02
HCN
CN
CN
+ M =
+ M =
+ OH
NH2
NO +
= CN
+ H2 = HCN
+ OH =
CN + 02 =
HCN
+ 0 =
CN + 0 =
NCO
+ H =
•• NCO
NCO
NCO
CO +
NH +
+ H + M
0 + M
+ H20
+ H
+ H
+ 0
+ H
N
CO
A(
5.
5.
1.
7.
6.
6.
1.
1.
2.
1.
5.
7.
1.
5.
2.
5.
1.
2.
6.
5.
3.
5.
6.
5.
2.
cm
mole
0 x
0 x
0 x
91 x
23 x
23 x
0 x
0 x
0 x
0 x
0 x
08 x
0 x
0 x
0 x
)
sec'
IO10
IO12
IO11
ID13
IO13
IO13
IO11
IO13
io11
IO11
IO11
IO13
io11
io10
IO16
75 x IO15
1 x
0 x
0 x
6 x
2 x
2 x
3 x
0 x
0 x
io16
IO11
IO12
io13
IO13
io12
io13
io11
io13
N
0.5
0
0.5
0
0
0
0.5
0
0.5
0.5
0.5
0
0.5
0.5
-0.5
0
0
0.6
0
0
0
0
0
0.5
0
E(cal/mole) References
3000
0
30,000
15,000
25,100
25,100
3000
2500
23000
-7000
0
2630
2000
3000
0
77,000
65,571
5000
5300
0
1000
8100
2100
6875
0
3,10
3,19
3,10
3,2
16
16
3,10
3,20
3,10
3,10
3,10
18.2
3,10
3,10
1,9,
17
17,2
3,10
21
22
21
23
21
15,*
25,*
*
*
,*
>
*
*
*
*
*
*
,n
,D
28
-------
Table 1. Fuel Nitrogen Mechanism (con't)
Reaction
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
75-
76.
77.
78.
79.
80.
81.
82.
83.
84.
85-
86.
87.
NCO + 0 =
CN +
CN +
CN +
CN +
CN +
CN +
CN +
CO +
CO +
co2
CO +
co2
CO +
CO +
CO +
H, +
H20
co2
OH =
HNO
H +
NH =
NH2
NH,
OH =
°2 =
+ M =
HNO
+ N =
N02
N20
H02
OH =
+ 0 =
H2 + 0 =
°2 4
H +
• H =
NO + CO
= NCO + CO
HCN + 0
= HCN + NO
M = HCN + M
HCN + N
= HCN + NH
= HCN + NH2
C02 + H
co2 + o
•• CO + 0 + M
= C02 + NH
= CO + NO
= C02 + NO
= C02 + N2
= C02 + OH
= H20 + H
= OH + OH
H + OH
0 + OH
0 + M = OH + M
02 + M =
H2-
H00
• M =
+ M =
0 + 0 + M
H + H + M
= H + OH + M
A(
5.
2.
3-
3.
4.
3.
1.
5.
7.
1.
3.
1.
1.
2,
2
1
1
2
6
1
2
8
3
2
1
• cm
\
•mole/secy
0 x
0 x
7 x
1011
1013
lO12
16 x 1012
0 x
1011
16 x 1016
0 x
0 x
0 x
1011
io10
1010
51 x 107
16 x 1012
,0 x
.0 x
.0 x
.0 x
.0 x
.0 x
.19
.76
.82
.19
.00
.55
.45
.29
io15
1011
1011
io12
io11
io11
x IO13
xlO13
x IO10
xlO12*
xlO15
xlO18
xlO111
x IO15
N
0.5
0
0
0
0.5
-0.5
0.5
0.7
0.7
1.3
0
0
0.5
0.5
0
0
0
0
0
1
0
0
-1
0
0
E(cal/mole) References
6875
0
0
3000
0
0
2000
2000
2000
-765
50,000
100,000
7000
30,000
30,000
20,000
10,000
5150
18,350
8900
16,800
0
118,000
96,000
105,000
25,*,D
26
3,7,*
3,10,*
3,10,*
3,10,*
10,*
10,*
3.27
3.28
3.29
3,10,*
3,10,*
3,30
3,31
3,32
18,2
18,2
18.2
18.2
20
33
18.2
18.2
29
-------
Table 1- Fuel Nitrogen Mechanism (con't)
Reaction
A(
mole sec
E(cal/mole) Reference
88. H + 02 + M = H02 + M 1.59 x 10
15
-1000
89. H02 + OH = H20 + 02 5.0 x 1013 0
1000
3,32
90. OH + 0 + M = H02 + M 5-O.x 10
16
91. H02 + 0 = 02 + OH 5.0 x 10
13
1000
3,32
92.
2.5 x 10
13
700
3,32
93. H02 + H = OH + OH 2.5 x 10'
900
3,32
94. H02 + H » H20 +0 1.0 x 1013 0
1000
3,32
30
-------
REFERENCES, TABLE 1
1. Bahn, G.S., Pyrodynamics 5_, 375 (1967); references therein.
2. Baulch, D.L., D.D. Drysdale, D. Home, and A.C. Lloyd, Evaluated Kinetic
Data for High Temperature Reactions, Vol. 1 (1972) and Vol.2 (1972),
Butterworths.
3. Engleman, V.S., "Survey and Evaluation of Kinetic Data on Reactions in
Methane/Air Combustion", EPA-6000/2-76-003, NTIS No. PB 248-139/AS,
January 1976; and extensive compilations and references therein.
4. Mayer, S.W. and L. Schieler, Aerospace Corp. Rept. TDR-669 (9210-02)-!
January 1966).
Schieler, L. and S.W. Mayer, Chemical Propulsion Information Agency Publ.
108 (June 1966).
5. Mayer, S.W., L. Schieler. and H.S. Johnston, Eleventh Symposium (Inter-
national) on Combustion, The Combustion Institute (1966).
6. Bortner, M.H., General Electric Missile and Space Division Report
#R63SD63 (August, 1963).
7. Benson, S.W., D.W. Golden, R.W. Lawrence, and R. Shaw, Quarterly Progress
Report No.2, EPA Grant #R-800798 (Feb., 1973).
8. Mayer, S.W. and L. Schieler, J. Chem. Phys. 45^, 385 (1966).
9. Thermochemistry Research Dept. Aerospace Corp. Rept. TR-100 (9210-02)-!
(Nov.1966).
10. Tunder, R., S. Mayer, E. Cook, and L. Schieler, Aerospace Corp. Rept.
TR-1001 (9210-02)-! (1967).
11. Kretschmer, C.B. and H.L. Petersen, J. Chem. Phys. 39_, 1772 (1963).
12. Mayer, S.W. and L. Schieler, Aerospace Corp. Rept. TR-669 (8210-02)-3
(June 1966).
13. Gehring, M. , et a!., Fourteenth Symposium (International) on Combustion,
The Combustion Institute (1973).
14. Alhens, E.A. et al., Twelfth Symposium (International) on Combustion,
The Combustion Institute (1969).
15. Private Communication, T. Corley, E.E.R. (1978).
16. Monat, J.P., R.K. Hinson, and C.H. Kruger, Comb. Sci. Tech. l£, 21 (1977)
17. Roose, T.R., R.K. Hinson, and C.H. Kruger, Eleventh International Shock
Tube Symposium, Seattle (July 1977).
18. McCullough, R.W., C.H. Kruger, and R.K. Hanson, Comb. Sci. Tech. 15, 213
(1977).
19. Phillips, L.F. and H.I. Schiff, J. Chem. Phys. 42, 3171 (1965).
200 Schofield, K., Planetary Space Sci. 15_, 643 (1967).
21. Albess, E.A. et al., Fifteenth Symposium (International) on Combustion,
The Combustion Institute (1975) .
22. B.S. Haynes, Comb, and Flame 28 , 113 (1977).
31
-------
23. Davies, P.B. and B.A. Thrush, Trans. Faraday Soc. 64_, 1836 (1968); low
temperature.
24. Boden, J.C. and B.A. Thrush, Proc. Roy. Soc. London A305, 107 (1968); low
temperature.
25. Mulvihill, J.N. and L.F. Phillips, Fifteenth Symposium (International on
Combustion, The Combustion Institute (1975); unjustified estimate.
26. Haynes, B.S., D. Iverach, and N.Y. Kirov, Fifteenth Symposium (Inter-
national) on Combustion, The Combustion Institute (1975); rate determined
by questionable interpretation of data.
27. Baulch, D.L. and D.D. Drysdale, Comb, and Flame 23, 215 (1974).
28. Dean, A.M. and G.B. Kistiakowsky , J. Chem. Phys. 53, 830 (1970); 54^
11718 (1971); Sulzmann, K.G.P., J. Chem. Phys. 42_, 3969 (1965).
29. Clark, T.C., A.M. Dean, and G.B. Kistiakowsky, J. Chem. Phys. 54^ 1726
(1971); Olschewski, H.A., et al., Eleventh Symposium (International)
on Combustion, The Combustion Institute (1967).
30. Kondratiev, V.N., Rate Constants of Gas Phase Reactions, English
translation, R.M. Fristrom, Ed., NTIS, Com-72-10014, (1972).
31. Lin, M.C. and S.H. Bauer, J. Chem. Phys. _50_, 3377 (1969); Micks, D.
and R.A. Matula, Fourteenth Symposium (International) on Combustion,
The Combustion Institute (1973).
32. Lloyd, A.C., Int. J. Chem. Kinetics £, 169 (1974).
33. Camae, M. and A. Vaughan, J. Chem. Phys. 34^ 460 (1960).
34. Peterson, H.L., and C.B. Kretschmer, Aerojet-General Comp. Dept. TN-38
(November I960).
* Calculated or estimated rate. Non-experimental
+ No data. The calculated value for NH + NH ->- NZ + H
Q Currently, neither value is preferred.
32
-------
Table 2a.
EER Reaction Set
• ATN expf-E/RT) (c.-n3; mole; sec
oo
REACTION
CH4"
CH30 *
tfCH-O -
CHO '»
co2 •*
H + NO
f H * 0
H T 02
CH + 0
* H2 ? H
H20 -
NO + 0
IN2 • N
«2°"
fc'O + 0
' CH4 +
CH4 *
CH4 +'
ru a. u
l«n« • n
CH20 •*• H
CKO + H
CO * H
CO + 0
* HNO
» OH
• H02
« H02
+ H
OH + H
• N02
+ N
N2 + 0
B°2
fit _ ru < f-\i
(*t\n a Cn^ * Un^
233
CN = HCN + CH3
H = CH3 + H2
r "
A
1.0 x 1017
4 x 1040
3.15 x 1017
2.50 X 1020
1.0 x 1015
2.0 x 1016
1.0 X 1018
"3.0.x 1015
1.6 x 1020
2.03 x 1015
2.30 x 1024
1.38 x 1021
4.0 x 1021
4 x 1014
1 x 1018
1.26 x 1012
3.16 x 1011
5.0 x 1010
N E(kcal/mo1e)
0 83.4
-7.5 22.6
0 87.
-1,5 16.8
0 100.
0 0
-1. 0
0 -1.0
-1.5 0
.07 103.83
-2.- 122.6
-1.82 0
-1.6 225.
0 51.4
-1.0 0
.70 20.
.70 5.
1. 10.
CCW.EMS*
Oppenhein et al (1975); (.71)
Benson (1975); estimate
Englema.n (1976); evaluation
Benson (1975); estimate
Engleman (1976)
Clyne and Thrush (1952); exp't.
Benson et al (1975); estimate
Baulch et al (1369); (2.); evaluation
Benson et al (1975); estimate
Mallard and Owen (1974)
Benson et al (1975); (3.); estimate
Michael et al (1976); exp't.
Baulc'n et al (1S73); evaluation
Axworthy (1977)
Benson et al (1975); estimate
Engleman (1976)
Engleman (1976)
Walker (1968); exp't.
-------
co
Table 2b .
REACTION
CH4 + OH » CH3 + H20
CH4 + 0 - CH3 + OH
f CH, + CN = HCN + CH,
'•5 ' C
*CH- + CH,6 « CH. + CHO
o 2 4
CH3 + OH - CH2 + H20
CH3 + OH « CH30 + H
CH3 + KKO ~ CH4 + NO
ICK3 + H02 = CH4 + 02
CH, + 0 » CH90 + H
J C
SCH3 + 02 - CH2 + H02
#CI!3 f 02 = CH20 + OH
CH3 + 02 - CH30 H- 0
/CH2 + CN " CH + HCN
|CH? + CHpO = CH, + CHO
CH2 + H = CH + H2
CH2 + OH » CH + H20
CH2 + OH • CH3 + 0
CH, + OH • CH,0 -1- H
jc,. - AT" m
A
3.0 x 1013
1.9 x 1014
1.0 x 1011
2. x 1011
2.0 x.1011
6.31 x 1011
5.0 x 1011
1.0 x 1011
2.6 X 1014
3.16 x 1012
9. x 1011
3,5 x 1013
3.16 x 1012
2.0 x 1011
3.16 x 1011
5.0 x 1011
5 x 1011
1.x 1013
f-P/RT)
N
0
0
.70
0
.70
0
.50
.50
0
0
0
0
0
0
.70
.50
.50
0
3
(era : mole: sec
E(kcal/ir.ole)
5.0
11.7
3.
6.5
2.
0
0
6.0
2.0
69.5
12.
28.8
5.
6.5
5.
6.
6.
5.
units}
COME NTS*
Wilson (1972); evaluation
Brabbs and Brokaw (1975); exp't
Engleman (1975)
Benson et al (1975); estimate
Engleman (1976); (3.); estimate
Englercan (1976)
Englerran (1976); estimate
Engleman (1976); estimate
Peeters and Vinckier (1975); exp't
Engleman (1976)
Tsuboi and Wagner (1974); exp't
Brabbs and Brokaw (1975); exp't
Engleman (1976)
Benson et al (1975); estimate
Engleman (1976)
Engletnan (1976); estimate
Engleman (1975)
Englemen (1976)
-------
Table 2c.
K, " ATN expf-E/aT) fern3; mole; s»c ur.UsI
GO
REACTION
CH
CH2
Ch'2
CH2
Ch'2
ICH +
CH +
CH +
fCH +
CH +
CH +
KH30
*CH30
i?CH30
eCH30
ICH.O
J
*CH30
CH20
+ H
+ N2
+ NO.
+ 0 =
+ C2
CH4
co2
OH =
H02
0 •
°2*
+ H
+ OH
+ N <
+ NO
+ 0 <
*P2
+ H '
= CH3 + H
= HCN + NH
= CH,0 + N
CHO + H
- CH20 + 0
= CH9 + CH,
c. o
» CHO + CO
CHO + H
- CH2 + 02
CO + H
CHO + 0
= CH20 + H2
- CH20 +' H20
= CH20 + NH.
• H.NO +• CH20
• CH20 + OH
• CH20 + H02
• CHO + H-
3.
,0
1.0
1.
5
5
1.
1.
5
1.
5
5.
1
3.
1.
5.
1.
1.
1.
6
X
X
0
X
X
X
X
X
X
16
X
A
xlO12
xlO14
1 9
x 10U
io"
1011
x IO12
IO10
IO11
IO10
IO11
10U
IO14
xlO13
10 14
0 x 1011
X
X
26
IO14
IO12
xlO10
N
0.
0
0
.50
.50
0
.50
.50
.50
.50
.50
0
0
0
.50
0
0
i:'
E(kc«l/nole)
7.0
60.
7,
4.
7.
17.1
6.
10.
15.
0
6.
0
0
0
4.23
0
6.
3.2
CO.XME.N7S*
Benson et al (1975); estimate
Benson et
Engleman
Engleman
Engleman
Estimate;
Engleman
Englexan
Engleman
Engleman .
Engleman
Engleman
Engleman
Engleman
Estimate;
Engleman
Englsrr.an
Engleman
al (1975); (CA « 70 ±20);
estimat.
(1976)
(1976); estimate
(197Sh estimate-
"under et al (1967-) msthocl
(1975)
(1976)
(1976)
(1975)
(1976)
(1976)
(1976)
(1976)
Tunder et al (1567) method
(1976)
(1976)
(1976)
-------
Table 2d.
CO
REACTION
CH20 + OH
CH20 + 0 »
fCHO +
ICHO +
fCHO +
if CHO +
5 CHO +
SCKO +
CHO +
CHO +
CHO +
KHO +
*CHO +
CHO +
ICHO +
HCfJ +
HCK +
HCN +
CHO
CH2
CH3
H «
HNO
CH =
H02
N »
N =
N «
NO »
0 *
0 «
« CHO
CHO
°CH2
«CH3
-CH4
CO +
- CH,
c.
CO +
• CH2
CH +
KCN +
CO +
CO +
CO +
co2 +
+ H20
+ OH
0 + CO
+ CO
+ CO
H2
0 + NO
H20
o + o2
NO
0
NH
HNO
OH
H
OH - CN + H20
N »
0 «
CH +
CH +
N2
NO
3.
2.
1.
3,
3.
3.
3.
3.
r.
1.
1.
2.
2.
6.
3.
2.
2.
1.
16
0
6
16
16
0
16
0
X
0
0
0
0
31
16
0
5
0
A
X IO10
xlO11
xlO11
x IO10
x 1011'
xlO10
x IO11
xlO10
IO14
x IO14
x IO14
x IO11
X IO11
x IO11
x IO11
x IO11
x IO11
xlO14
N E(kcaVmole)
1. 0
1. 4.4
.50 0
.70 1.
.70 0
1. 0
.50 0
1. 0
0 3.
0 48.6.
0 0
.50 2.
.50 2.
1.0 0.5
0 0
.60 5.
0 16.
0 72.
Englenan
Englenan
Engleman
Englerr.an
Englsman
CCJWtNTS*
(1976)
(1976)
(1975)
(1976)
(1976)
Engleman (1975),
Er.glecan
Englen-.ao
Engleman
Engleman
Englemsn
Engleman
Engleman
Engleman
Engleman
Englerr.an
Benson et
Benson et
(1575)
(1976)
(1976)
(1975); estimate
(1976)
(1976)
(1976); estimate
(1976); (2.)
(1976)
(1976)
al (1975); (2.5); estiir-ate
al (1975); estimate
-------
CO
Table 2e .
REACTION
CN +
jfCN +
CN +
CN +
#CN +
£
CN +
co2
OH «
OH =
H2 =
f.'H «
NO «
CN + 0 »
|
s
CN +
NCO
CO +
CO +
CO +
°2a
+ H =
KM
OH -
•HO
w
f?CO + 0, «
s
a
3
L* Vjrt
H +
H +
H +
+ N -
H?;O »
HN'O =
OH =
» NCO
HCN +
NCO +
HCN +
CH +
CO +
CO + N
CO +
NH +
= co2
co2 +
- CHO
co2 +
CO +
H2*
Nil +
+ CO
0
H
H
N2
N2
NO
CO
+ NH
H
+ 02
• 0
NO .
NO
OH
H0 -H 0
3
3
6
6
1
3
6
3
5
1
1
3
3
2
1
2
2
.72
.16
.2
.2
.0
.0
.31
x
'. X
. X
.51
.0
JC - ATN exof-E/RT) (cm2: nvj'l»: s»c uMtO
A
xlO12
xlO12
xlO13
x 10
xlO14
XlO11
xlO11
1011
1011
10U
"x 107
xlO12
.16 x 1012
.0
.0
.0
.71
x 1011 .
XlO13
xlO11
x 10 17
N
0
0
0
0
0
0
.50
0
.50
.50
1.3
0
0
.50
0
.50
-.94
E(kcal/mole)
0
3.
0
5.3
40.
0
0
0
5.87
7.
-.765
37.1
50.
25.
2.5
23.
14.69
COM'-IE.'iTS*
KorUy (1976); estimate
Engleaan
(1S76)
Korlsy (1S76); estimate
MorTey (1976); estimate
Benson et
Er.glerr.an
Senson et
EngleTian
Estir-ata;
Estimates
al (1975); estimate
(1976)
al (1975); estimate
(1976)
Tundsr et al (1957) ratr.GS
; Tur.der et al (1967) -ethod
Baulch and Orysdale (1974)
Benson et
Englenan
Engleman
Engle^an
Engleman
al (1975); estimate
(1976)
(1976)
(1976)
(1976)
Schott et al (1972); exp't
-------
CO
oo
Table 2f.
REACTION
H + H02 « OH * OH
H + N20 - OH + N2
H •*• N20 « NH + NO
H + N02 » OH + NO
I UNO + HNO » N£0 + H20
KNO + OH * H20 + NO
§H:;O + NO - OH + N£O
KNO + 0 » OH + HO
H.\o + o <* 'NH + o2
OH + H2 • H + H20
CH + OH • H20 + 0
OH -f N20 * H02 + N2
CH + 0 • H + Og
H02 + H = 02 -t- H2
H02 + OH » H£0 + 02
H02 + 0 « OH + Og
fj + OH « NO + H
N + NO = N0 + 0
Kf - A7N e
A
2.50 x 1014
8.0 x 1013
1.0 x 1011
3.16 x 1014
1.0 x.1010
1.0 X 1012
2 x 1012
5.0 x 1011
1.0 x 1011
2.5 x 1013
6.0 x 1012
3.16 x 1013
6.31 x 1011
2.5 X 1013
5.0 x 1013
5.0 x 1013
6.31 X 1011
3.10 X 1013
Xof-E/RT^
N
0
0
.50
0
.50
0
0
.50
.50
0
0
.0
.50
0
0
0
.50
0
Vcm3: lioist sec
E(kcal/inole)
1.9
15.
30.
1.5
41.55
.1.0
25.
0
7.
5.?
1.
15.
0
.70
1.
1.
o
.334
units!
COME.NTS*
Englcrnan (1975); evaluation
Englercan (1975)
Englenan (1976); estimate
Engleiran (197G),
Estimeta; Tuncer et al (1557) m«thc-d
Engleman (1976)
Englenan (1976); evaluation
Englenan (1975); estimate
Englerr.an (1976)
Baulch et al (1972); evaluation
Baulch et al (1972); evaluation
Engleman (1976)
Benson et al (1975); estimate
Engleman (1976)
Engletnan (1976)'
Er.gierr.an (1976)
Benson et al (1975); estimate
Englenan (1976)
-------
co
Table 2g.
REACTION
f N + N02 - M2 + 02
#N + N02 « NO + NO
H + 02 « NO + 0
NH •*• H » N + H2
NH + OH - H20 + N
NH + OH - NO + H2
JNH + 0 • N + OH
NH + 0 = NO •+ H
?NH + N « H 4- N2
S NH + NH. = N2 + H2
fNH + NO • N2 * CH
NH2 + H H NH * H2
«H2 + CH = NH + H2Q
NH2 + 0 " NH + CH
Kf - ATN exof-E/RT) • fcm3: mole: sec
A
1.0 x 1012
4.0 X IO12
6.0 X IO9
6.31 x IO11
5.0 x.1011
5.0 x IO11
1.6 x 1012
1.7 xlO10
8'.4 x IO12 •
3.16 x IO11
1.0 x IO12
6.31 x IO11
6.0 x IO11
3.6 x IO11
2.4 x IO12
1.4 x IO11
3.0 x IO10
9.2 x IO11
N
0
0
1.
.50
.50
.50
.55
.70
.70
.50
.50
.50
.50
.55
0
.67
.63
.50
E(kcal/rr.ole)
0
0
6.3
8.0
2.
2.
1.5
.10
.10
8.
.10
0
0
1.9
0
4.3
1.3
0
units')
COMMENTS*
Englemarr(1976)
Engleman (1S76)
Engleman (1976); evaluation
Benson et al (1975); estimate
Er.glemen (1976); estimate
Presently used
Sarofim et al (1973)
Presently used
Sarofim et al (1973); .estimate
Engle^an (1976); esti/r.ate
Bahn (1968); estimate
Benson et al (1975); estimate
Englemen (1976); estimate
Sarofim et al (1973)
Sarofim et al (1973)
Sarofim et al (1973)
Sarofim et al (1973)
Presently used
-------
•£»
O
Table 2h. A?N ^
REACTION A
NH2 + 02 » NH + H02 1.0 X 1013
NK2 + NK2 - NK3 + NH 1.7 X 1011
NH- + NO » N2 + H20 5.0 X 10 12
NH3 + OH - NH2 + H20 1.26 X 1010
NH3 + H * NH2 + H2 1.9 X 1011
WH3 + 0 « NH2 + OH 1.5 X 1012
NH, + 0- « NH, + HO, 5.0 x 1011
J b Lt **
*,N20 + 0 • N2 + 02 -1.0 X 1014
*N?0 + 0 « NO + NO . 1.0 X 1014
(?HO * OH • HOg •»• N 5.0 X 1010
NO + HO, « NO, + OH 5.0 x 1011
-------
Table2i.
REACTION
INO + NO "NO + 0.
JN02 + 0 * NO + 02
iCtt + CH3 » CH2 + CH2
Kf - ATN CXD(-E/RT)
A .N
1.0 x 1012 0
1.0 x 1013 0
3.2 x 1012 0
(en : mole: sec uMts^
E(kca1/rro1e}
60. Engl^fnsn
1. Englercan
8. EngTeman
CO.'
(1975)
(1975)
(1976);
«Eh7S*
estlrate
* Number in parenthesis indicates factor by which original rate was multiplied.
-------
REFERENCES, TABLE 2
1. Axworthy, A., Private Communication (1977).
2. Bartok, W., V.S. Engleman, and E.G. del Valle, "Laboratory Studies and
Mathematical Modelling of NOX Formation in Combustion Processes", Exxon
Research and Engineering Company Report No. GRU-3GNOS-71, EPA No. APTD1168
NTIS No. PB 211-480, 1972.
3. Baulch, D.L., D.D. Drysdale, D.G. Horne, and A.C. Lloyd, "Evaluated
Kinetic Data for High Temperature Reactions. Vol. 1. Homogeneous Gas Phase
Reactions of the H2-02 System", CRC Press (1972).
4. Baulch, D.L., D.D. Drysdale, D.G. Horne, and A.C. Lloyd, "Evaluated
Kinetic Data for High Temperature Reactions. Vol. 2. Homogeneous Gas
Phase Reactions of the H2-02 System", CRC Press (1972).
5. Baulch, D.L., D.D. Drysdale, "An Evaluation of the Rate Data for the
Reaction CO + OH -> C02 + H", Comb. JFlame, _23 (1974).
6. Benson, S.W., D.M. Golden, R.W. Lawrence, R. Shaw, and R.W. Woolfolk,
"Estimating the Kinetics of Combustion: Including Reactions Involving
Oxides of Nitrogen and Sulfur". Environmental Protection Agency, Office
of Research and Development, Washington, D.C., Pub. No. EPA-600/2-75-019
(1975).
7. Bowman, C.T., "An Experimental and Analytical Investigation of the High-
Temperature Oxidation Mechanisms of Hydrocarbon Fuels", Comb. Sci. Tech.,
2 (1970).
8. Clyne, M.A.A. and B.A. Thrush, Disc. Faraday Soc. 33, 139 (1962).
9. Dove, J.E. and W.S. Nip, "Shock Tube Studies of the Reactions of Hydrogen
Atoms. I. The Reaction H + NH-j -»• H2 + NH2 , Can. J. Chem., 52^
10. Duxbury, J., and N.H. Pratt, "A Shock Tube Study of NO Kinetics in the
Presence of H2 and Fuel-N", Fifteenth Symposium ^International) on
Combustion, The Combustion Institute, Pittsburgh, Pennsylvania (1975).
11. Engleman, V.S., W. Bartok, J.P. Longwell, and R.B. Edelman, "Experimental
and Theoretical Studies of NOX Formation in a Jet-Stirred Combustor",
Fourteenth Symposium (International) on Combustion, The Combustion
Institute, Pittsburgh, Pennsylvania (1973).
12. Engleman, V.S., "Survey and Evaluation of Kinetic Data on Reactions in
Methane/Air Combustion", U.S. Environmental Protection Agency, Office of
Research and Development, Washington, D.C., Environmental Protection
Technology Series, Pub. No. EPA-600/1-76-003 (1976).
]3. Engleman, V.S., "Mechanism and Kinetics of the Formation of NO and Other
Combustion Pollutants: Phase I, Unmodified Combustion", EPA-600/7-76-009a
(1976).
14. Fenimore, C.Po, Thirteenth Symposium (International) on Combustion, p.373,
The Combustion Institute (1971).
15. Fenimore, C.P., "Reactions of Fuel-Nitrogen in Rich Flame Gases", Comb.
Flame, 26 (1976).
42
-------
16. Kaskan, W.E. and D.E. Hughes, "Mechanism of Decay of Ammonia in Flame
Gases from an NH3/02 Flame", Comb. Flame. 20 (1973).
17. Lesclaux, R, P.V. Khe, P. Dezauzier, and J.C. Soulignac, "Flash
Photolysis Studies of the Reaction of NH2 Radicals with NO", Chejn. Phys.
Letters. 35, No., 4(1975).
18. Mallard, W.G. and J.H. Owen. Intern. J. Chem. Kinetics^, 6_ (1974).
19. Michael, J.V., Payne, W.A., and Whytok, D.A. , "Absolute Rate Constants
for 0 + NO + M (=He, Ne, Ar, Kr) ->• N02 + M from 217-500"K," J. Chera. Phy.s.
65, No. 11 (1976).
20. Morley, C. , "The Formation and Destruction of Hydrogen Cyanide from
Atmospheric and Fuel Nitrogen in Rich Atmospheric -Pressure Flames",
Comb. Flame, 27 (1976).
21. Oppenheim, A.K. , L.M. Cohen, J.M. Short, R.K. Cheng, and K. Horn,
"Modern Developments in Shock Tube Research", 10th International Shock
Tube Research , (G. Kamoto, Ed.) Kyoto (1975).
22. Peeters, J. and C. Vinckier, "Production of Chemi-Ions and Formation of
CH and CH2 Radicals in Methane-Oxygen and Ethylene-Oxygen Flames",
Fifteenth Symposium (International^ on Combu.s^ion^, The Combustion
Institute, Pittsburgh, Pennsylvania (1975).
23. Sarofim, A.F., G.C. Williams, M. Modell, and S.M. Slater, "Conversion of
Fuel Nitrogen to Nitric Oxide in Premixed and Diffusion Flames", Paper
Presented at AIChE 66th Annual Meeting, Philadelphia, Pa. (1973).
24. Schott, G.L., R.W. Getziner, and W.A. Seitz, 164 Amer. Chem. Soc. Meeting
New York (1972).
25. Tsubi, T., and H.Gg. Wagner, "Homogeneous Thermal Oxidation of Methane
in Reflected Shock Waves", Fifteen thjSymposium ( Inter national) on
Combustion, The Combustion Institute, Pittsburgh, Pennsylvania (1975).
26. Tunder, R. , S. Mayer, E. Cook, and L. Schieler, Aerospace Corp. Report
No. TR-001 (9210-02), (1967).
27. Walker, R.W. , J. Chem. Soc. (A) 1968, 2391 (1968).
28. Wilson, W.E., J. Phys^ Chem. Ref. Data, 1 (1972).
29. Zellaer, R. , and I.W.M. Smith, "Rate Constants for the Reactions of
OH with NH3 and HN03", Chem . _Phys_. Letters , 26_, No. 1 (1974).
43
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REFERENCES, TABLE 3
Biordi, J.C., C.P. Lazzara, and J.F. Papp, Fifteenth Symposium
(International) on Combustion, p. 917, The Combustion Institute, Pittsburgh,
Pa. (1975).
Dixon-Lewis, G., M.M. Sutton, and A. Williams, "Tenth Symposium
(International) on Combustion, The Combustion Institute, p. 495, Pittsburgh,
Pa. (1965).
Merryman, E.L. and A. Levy, "NOX Formation in CO Flames", Report to EPA,
Contract #68-02-0262 (January 1977).
Peeters, J. and G. Mahnen. Fourteenth Symposium (International) on
Combustion, The Combustion Institute, p. 133, Pittsburgh. Pa. (1973).
44
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HETEROGENEOUS PROCESSES INVOLVED IN
THE CONTROL OF NITROGEN OXIDE FORMATION
IN FOSSIL FUEL FLAMES
By:
M. P. Heap and T. J. Tyson
Energy and Environmental Research Corporation
Professor A. F. Sarofim
Massachusetts Institute of Technology
Professor J. 0. L. Wendt
University of Arizona
-------
ACKNOWLEDGMENTS
Both of us (M.P.H./T.J.T.) take pleasure in acknowledging the
contribution made to the FCR program by many individuals on the staff at
EER or at the various subcontractors, as well as several university con-
sultants, all of whom make working on this program a pleasure. This paper
has drawn on information generated by several subcontractors at various
organizations. Axworthy at Ricketdyne; Solomon at UTRC; Trolinger at SDL;
De Soete at IFF; Tong at Acurex; and Overley at Battelle. We would also
like to acknowledge the contribution made by Professor Samuelsen of the
University of California, Irvine, who provided constructive criticism and
helpful advice concerning the various programs, together with concepts and
ideas for new work. We would also like to express our appreciation to
Mr. W. S. Lanier, the EPA Project Officer for the FCR program, and to his
colleagues at the CRB for their continued interest.
46
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SECTION 1
INTRODUCTION
The general philosophy and overall objectives of the FCR* program have
been described elsewhere (1). This program involves the planning and
direction of several projects whose overall goal is to provide the EPA/CRB
with the necessary understanding of the fundamental behavior of combustion
systems to develop control technology which will minimize the emission of
both NOX and associated pollutants from stationary sources. The program is
focused on well-defined priority target areas, and the research effort is
directed towards providing engineering .solutions to specific problems within
a time frame consistent with the technology development programs. Neither
the time nor resources are limitless, and the program has been planned to
provide products which can be realized in both the near and far-term.
Information is being generated now which can either be directly transferred
to "technology development" programs, or used in the development of empirical
engineering models to aid the designer of low NOX combustion systems. Pro-
jects with a long-term payoff, which are in the minority, are associated with
the development of numerical models capable of describing pollutant forma-
tion in complex combustors.
The FCR program is primarily concerned with the basic mechanisms asso-
ciated with the formation and destruction of nitrogen oxides in fossil fuel
flames. However, some effort has been initiated relating to the formation
of soot and fine particulate matter, as well as the mechanisms of sorbent
extraction of S02 in flames. Reviewing the sources of anthropogenic NOX
emissions, it can be seen that approximately 50 percent can be attributed to
stationary combustion; and of this, 50 percent greater than 55 percent is
associated with the combustion of nitrogen-containing fuels which are mainly
Fundamental Combustion Research Applied to Pollution Control
47
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coal or oil. Thus, the primary initial objective was to focus upon pollutant
production in one-atmosphere turbulent diffusion flames burning pulverized
coal or residual oil and radiating to cold walls. Since the increased use
of coal is one of the nation's methods of achieving energy independence,
this initial objective has considerable relevance because any increase in the
use of coal or coal—derived fuels without the application of necessary control
technology will probably result in an increase in NO emissions.
X
A key element of the FCR program is the establishment of the lower bounds
set on NOX emissions under various limiting situations and constraints. It is
important when assessing control strategies to know that for a particular set
of process requirements that there exists a limit on the level of control
achievable by combustion modifications and set by these requirements. Thus,
the value of studies leading to the establishment of lower bounds is not only
that they provide a yardstick by which to measure the effectiveness of other
control schemes, but they also provide strong guidance in the development of
advanced control techniques.
The generation of nitrogen oxides during the combustion of pulverized
coal and residual oil in turbulent diffusion flames involves the complex
interaction of several physical and chemical phenomena. Transport processes
involving heat or mass, gas phase kinetics, and heterogeneous processes are
all involved in the formation and destruction of NO in these flames. This
paper describes projects included in the FCR program, both ongoing and planned
for the future, which can be classified as heterogeneous processes. Projects
associated with mass transfer phenomena and homogeneous gas phase kinetics
are discussed in two other papers.
48
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SECTION 2
FCR APPLICATIONS
The purpose of the FCR program is to provide development engineers
with information and tools which will aid in the application of NOX control
technology to stationary combustion sources. More specifically, the primary
objective involves large water-wall combustors burning pulverized coal or
residual fuel oil. The ultimate goal is to combine information generated
from the three major program elements in order to describe pollutant forma-
tion in large industrial flames. However, in this the second year of the
program, the potential applications are much more restricted, and are more
concerned with the direct transfer of information to aid in the interpreta-
tion of development results.
The program element concerned with heterogeneous processes can be placed
in context by considering the experimental results presented in Figures 1 and
2. These data were generated in programs designed to generalize low NOX
burner technology for solid and liquid fuels, and to determine the role of
fuel composition on NOX emissions. Figure 1 presents a composite plot show-
ing the conversion of fuel nitrogen to NOX as a function of weight percent
nitrogen in the fuel on a dry, ash-free basis. The results were generated
in two different furnaces with different but similar burner systems. Mini-
mum NOV emissions obtained with the same fuels for a simple staging system
A
are shown in Figure 2. The results are somewhat unexpected, but because
they are of great practical importance, they clearly demonstrate the need
for further interpretation through this FCR program element. Only then can
their general impact be recognized and translated to practice in the field.
The observables presented in Figures 1 and 2 can be summarized by:
— In overall lean conditions fuel nitrogen conversion to NOX for
liquid fuels appears to depend very strongly on the weight per-
cent nitrogen in the fuel. This is not unexpected. However,
49
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for solid fuels there is apparently some other parameter
controlling fuel nitrogen oxidation, and NO does not appear
to depend primarily on coal N content. FCR will help identify
this other parameter.
— There are secondary parameters involved in fuel nitrogen forma-
tion in liquid fuels which are probably associated with the
volatility of the fuel nitrogen compounds (2).
— Fuel nitrogen conversions in alternate liquid fuels are higher
than those for solid fuels with similar nitrogen contents.
— Under staged conditions minimum NOX emissions appear to be less
dependent upon fuel nitrogen content, although both coal and
oil properties appear to influence minimum NOX levels.
— There is a strong effect of the particle/droplet size. Minimum
NOX emissions under staged combustion conditions for the same
coal vary by over 30 percent when coal is burned with a particle
size of 165 ]aa. or size less than 39 ym. Smaller particles give
lower emissions staged, but higher emissions unstaged. Similarly,
with liquid fuels minimum NOV emissions increase from 110 to
A
130 ppm as the mean droplet size varies from 20 to 180 um.
These experimental results were obtained from specific simple com-
bustors, described elsewhere (2). It is the function of this FCR program
element to determine if, why, and when they hold in general, especially
under advanced combustor design conditions. Interpretation of these results
is complicated because of both fuel effects and fuel/air contacting effects.
One goal of the heterogeneous program element is to ascertain under which
conditions these two factors play a dominant role.
The combustion of liquid or solid fuels involves several processes.
Before heat release can occur the fuel must undergo some physical trans-
formation, i.e., pulverization or atomization, to provide for efficient
fuel/air mixing and minimize combustion time. The coal particles or droplets
are heated either by convection from the surrounding gases, or by radiation
from the chamber walls or adjacent flames. During heating the fuel decom-
poses producing light gases, tars, and leaving a solid char. The tars may
50
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themselves pyrolyze and the gases produced either directly or from this
secondary pyrolysis process are burned in premixed or diffusion controlled
heat release zones. The char remaining after devolatilization and any solid
produced by pyrolysis reactions in the gas phase are then oxidized. Several
questions can be raised concerning the fate of fuel nitrogen during these
processes which, if answers were available, might well help to explain
some of the results presented in Figures 1 and 2. These questions are:
• Do fuel properties affect the distribution of nitrogen between
the light gases, tars and char formed during thermal decomposition?
• Do fuel properties affect the rate of nitrogen loss as a function
of temperature, gaseous environment, and particle droplet size?
• Is the speciation of nitrogen evolved during thermal decomposi-
tion fuel-dependent?
• What is the fate of nitrogen remaining in the char?
• Under what condition do NO, NH and HCN react with solids?
• How does particle size control particle temperature and its
subsequent devolatilization?
One of the goals of the FCR program is to define lower bounds on N0x
emissions, and in concluding this section on potential applications it is
worthwhile considering a control scheme whose limits are set by the kinetics
of heterogeneous processes. Assuming that char nitrogen converion to N0x
is finite, then one low M) concept could involve the design of a combustor
X
with the following features:
— A rich, high temperature zone to extract nitrogen from the solid
phase.
— A hold up zone to maximize N2 production by homogeneous or
heterogeneous reactions.
— Burnout in a diffusion flame with the required composition to
maximize HCN, NH3, NO conversion to N2-
The information required to design such a combustor is an example of what will
be generated in the heterogeneous process program element.
51
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SECTION 3
HETEROGENEOUS PROCESSES — AN FCR PROGRAM ELEMENT
Figure 3 presents a schematic showing the relationship between the
heterogeneous processes program element and the other FCR program elements:
• Homogeneous Kinetics
• Transport Processes
• Measurement System Assessment/Development
• Numerical Model Development
The variqus projects under this program element can be classified under three
major headings which are:
— Thermal Decomposition
— Gas Solid Reactions
— Reactor Studies
Figure 3 shows the Principle Investigators associated with the projects
in each of the areas.
THERMAL DECOMPOSITION STUDIES
During the initial stages of a flame liquid fuel droplets and pulverized
coal particles are heated rapidly, causing both physical and chemical changes
to occur which affect pollutant formation. Two projects have been initiated
which are concerned with the fate of fuel nitrogen during the thermal decompo-
sition process. Axworthy is conducting an investigation of the volatility of
nitrogen compounds present in fossil fuels, and Solomon has just begun a pro-
ject to characterize four coals during thermal decomposition.
A quartz two-stage pyrolysis reactor was developed by Rocketdyne under
EPA Contract 68-02-1886 (3). Liquid or solid fuels are pyrolyzed rapidly
under inert conditions in the small volume first stage reactor. The volatile
52
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pyrolysis products are swept by helium carrier gas into a second stage
stirred flow reactor where they can be (1) pyrolyzed further in helium at
a different temperature; (2) mixed with oxygen and undergo oxidative pyrol-
ysis and oxidation; or (3) condensed and collected for chemical analysis.
This reactor was used to establish that (1) most of the HCN forms from the
secondary pyrolysis of volatile primary pyrolysis products; (2) the fuel
nitrogen in coal liquids and shale oils are apparently more volatile than
nitrogen in conventional fuels; and (3) the volatility of fuel nitrogen in
coals varies considerably from coal-to-coal. The objective of the program
being carried out by Axworthy is to measure and compare the volatility
characteristics of reactive fuel nitrogen in liquid and solid fuels. This
information is needed to both qualitatively explain observations described
in Section 2, as well as provide information on the rate of evolution of
volatile nitrogen from various fuels in order to develop a semi-empirical
model of the conversion of fuel nitrogen to NO and N2 in flames. The fuels
to be studied in this program are those that have been used in other CRB
development programs.
Figure 4 presents an example of some of the initial data comparing the
volatility of convertible fuel nitrogen for a variety of fuels as a function
of first stage pyrolysis temperature. It can be seen that the shale and
shale-derived diesel fuel have large fractions of volatile fuel nitrogen com-
pounds which are evolved at low temperatures. Greater than 60 percent of
the initial fuel nitrogen can be converted to HCN at pyrolysis temperatures
greater than 300°C. This can be compared with the results presented for
snythol, a coal-derived liquid which shows a similar behavior but only 40 per-
cent of the fuel nitrogen is converted to HCN. The data for the three
petroleum-derived residual fuels shows a more gradual evolution of nitrogen
from the oil, but also that different oils have different characteristics.
Although the final conversions for the Gulf Coast and Alaskan oils are similar,
the effect of temperature on volatile nitrogen evolution is very different.
The Gulf Coast oil appears to have a large component of refractory nitrogen.
Axworthy's experiments were designed to provide a rapid screening tool
to identify large differences in the volatility of fuel nitrogen compounds
for a wide range of fuels in order to select those more suitable for more
53
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detailed study. A different project has been initiated at the United
Technologies Research Center under the direction of Solomon which will
involve the use of vacuum distillation equipment (4) and a high temperature
furnace to characterize the thermal decomposition of four coals using infrared
analysis. The characterization includes the definition of the coal structure
including sulfur and nitrogen groups, and the determination of the rates and
products of thermal decomposition. The investigation will also include a mea-
surement of nitrogen group decomposition in tars. This rate will be measured
by thermally decomposing tar in a high temperature furnace with in situ
infrared analysis of products which will be capable of detecting HCN and Nt^.
The information on the rates of these thermal decomposition processes will
be incorporated in the coal combustion model. Given the time/temperature
history of a coal particle, prediction of the volatile yield and volatile
composition (including sulfur and nitrogen distribution) will be possible.
This information can then feed directly into a combustion model for pul-
verized coal which include gas phase combustion kinetics, char kinetics, heat
and transport processes.
Coal particles undergo both chemical and physical changes during thermal
decomposition. Physical effects such as swelling, shattering, and method of
off-gasing, etc., will have a significant influence upon the formulation of
any model which attempts to describe pollutant formation during the combus-
tion of pulverized coal particles. A proof-of-principle experiment was car-
ried out with Trolinger of Spectron Development Laboratories to determine
whether holography could be used to observe coal particles during thermal
decomposition in flames. Success of the technique would depend upon its
ability to distinguish particles whose size is the same as those used in
practice, and in a thermal environment similar to a turbulent diffusion flame.
The physical behavior of coal particles during heat up has been observed
photographically in the past. However, these experiments involved larger
coal particles heated either upon grids or platinum ribbons. Holography
provides the opportunity of producing high resolution images of individual
particles in a dynamic particle field array, i.e., under typical combustion
conditions.
54
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Holography has been applied to the study of several combustion phenomena
(5) with varying degrees of success. One of the principle problems is associ-
ated with loss of resolution caused by the imaging through a turbid medium
associated with combustion, and it was found that the application of certain
optical and mechanical techniques allowed the observation of burning coal
particles in free flight with nearly diffraction-limited capability. Although
holographic interferometry has been used extensively to study flow fields and
density gradients in gases, the primary problem in this application of inter-
ferometry is the high sensitivity required because the distances involved are
so small. The holo camera developed by Trolinger used in this investigation
is shown in Figure 5. The-required high resolution was achieved by (1) magni-
fying with high quality lenses before recording; (2) using near image plan
holography to further relax hologram requirements; and (3) precisely aligning
the hologram during reconstruction. Coal particles of approximately 15 ym
mean size were injected into the combustion products of a methane/air flat
flame through a rectangular slit. Holograms were produced under a wide
variety of conditions and at various locations above the injection point.
Holographic interf erometry was used to examine phase characteristics of the
region around coal particles in the flame. This included double pulse,
double exposure, double plate, and sheared wave front hologram interferometry
(5). Double-pulsed hologram interferometry proved especially useful for
examining dynamics, while double exposure proved useful for high sensitivity
flow visualization. In other of these cases the gross phase shift created
by the methane/air flat flame was removed from the final interferogram, a
desired feature of hologram interferometry.
As stated earlier, the main objective of the study was to determine the
utility of holography for viewing burning particles, and from this viewpoint
the experiment was an unqualified success. Phenomena observed included:
— Single particles down to A ym
- Evolution of high molecular-weight gases from single coal
particles
55
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— Formation of a sphere of small particles (soot) around single
particles and separation of the coal particle from the sphere
probably due to relative motion of the gas and coal particle
— Coal particle swelling
— Coal particle disintegration
— Production of particles with a high length-to-diameter ratio
which are probably soot caused by pyrolysis of the gaseous
devolatilization products.
A program has been planned to continue with the use of this technique to
investigate both chemical and physical effects during the thermal decompo-
sition of both liquid and solid fuels.
GAS SOLID REACTIONS
At this time the FCR program is primarily interested in two heterogeneous
processes concerning gas solid reactions which affect NO production. These
are the fate of char-bound nitrogen and the reduction of NOX on particulate
matter yielding N£. Some activity at MIT touches on the former subject, and
it is planned to expand the study of char nitrogen oxidation in the near
future.
De Soete at the Institut Francais du Petrole is currently investigating
the reduction of nitrogen oxides by particulate matter in the presence of
combustion products. Beer et al. (6) have demonstrated that NO can be reduced
by char in fixed bed experiments. This phenomenon may prove to be of practi-
cal importance as an NOX control technique. Preliminary work by De Soete (7)
indicated that the reduction mechanism was enhanced by the presence of hydro-
gen and CO and inhibited by the presence fo small quantities of oxygen.
De Soete also measured the decay of NO when NO/Ar mixtures were injected
downstream of the flame front of a sooting flame. Typical results are pre-
sented in Figure 6 showing that the NO reduction mechanism can be significant.
Currently, De Soete is working on a project which involves investigation of
adsorption and desorption rates of nitric oxide on solid particles as well
as determining the kinetic rates for decomposition by several different parti-
cles, e.g., flame-generated soot, fly ash, etc. One of the initial findings
56
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was that the presence of carbon was not mandatory, and NO could be reduced
by the high temperature refractory walls of the experimental reactor. These
results have already been transferred to the developmental programs, and
have been used both to design the proper experimentation for the programs and
to interpret ensuing data.
REACTOR STUDIES
The principle goal of the reactor studies is to provide information on
the fate of fuel nitrogen during the combustion of solid and liquid fuels in
well-defined fluid dynamic conditions. The information generated in the
thermal decomposition and gas solid reaction investigations will provide
rate data to allow interpretation of the results generated by the reactor
studies provided the fluid mechanical conditions are well-stirred or plug
flow (or combinations of the two). Thus, the reactor studies will not only
provide experimental information but a proof of simple engineering models
which can later be applied to more complex combustion systems. A project is
underway at Acurex under the direction Tong to determine the fate of coal
nitrogen as a function of particle size, air/fuel ratio, temperature and
residence time in a well-stirred reactor. The study of Overley at Battelle
involves a similar goal with liquid fuels. It should be recognized that
these experiments involve complex design problems in order to ensure that
the gas phase is well-mixed, and that the residence time of the solid or
liquid phase is known. These problems are complicated because residence
times of interest are of the order of 20 to 100 msec rather than 1 or 2 msec.
To date, both projects have progressed to the point which allows com-
bustion studies to begin with well-characterized reactors. Tracer studies
have been employed by both investigators to measure the residence time dis-
tribution of both phases.
57
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SECTION 4
SUMMARY
This paper has discussed the heterogeneous processes program element
of the FCR program. Several projects have been initiated to determine the
fate of fuel nitrogen during the combustion of both solid and liquid fuels.
Three programs are concerned with the chemical and physical effects occurring
during thermal decomposition. One program is underway to investigate NO
reduction by solids in the presence of combustion products, and two reactor
studies have been initiated to investigate fuel nitrogen conversion under
well-backmixed conditions. Two additional programs are planned. One con-
cerned with the oxidation of char nitrogen, and the other a series of
reactor studies to provide time-resolved nitrogenous species under controlled
mixing history conditions with both solid and liquid fuels. The information
generated by these programs is currently being applied to interpret data
generated by several development programs as well as aiding in the develop-
ment of empirical engineering tools.
To date, the FCR program has concentrated upon nitrogen oxide formation.
Future effort in the heterogeneous processes program element will include
investigations directed toward the formation of fine particulate matter
from inorganic material in coal, the formation of soot, and the absorption
of sulfur specie by calcium and sodium-containing sorbents.
58
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REFERENCES
1. Tyson, T. J. and M. P. Heap, "Fundamental Combustion Research Applied
to Pollution Control", EPA Second Stationary Source Combustion
Symposium, New Orleans, September 1977.
2. Heap, et al., "The Influence of Fuel Characteristics on Nitrogen Oxide
Formation — Bench-Scale Studies". Paper to be presented to EPA Third
Stationary Source Symposium, San Francisco, March 1979.
3. Axworthy, A. E. and V. H. Dayan, "Chemical Reactions in the Conversion
of Fuel Nitrogen to NOX: Fuel Pyrolysis Studies", presented at the
Second EPA Stationary Source Combustion Symposium, New Orleans,
September 1977.
4. Solomon, P. R., "The Evolution of Pollutants During Rapid Devolatiliza-
tion of Coal", Report NSF/RA-770422, NTIS No. PB 278496/AS.'
5. Trolinger, J. D., "Laser Instrumentation for Flow Field Diagnostics",
Agardograph No. 186, NATO Advisory Group for Aerospace Research
(AGARD) (1974).
6. Beer, J. M., A. F. Sarofim, L. K. Chan, -A. M. Sprouse, "NO Reduction by
Char in Fluidized Combustion". Presented at the Fifth International
Fluidized Bed Combustion Conference, Washington, D.C. (December 1977).
7. De Soete, G. G. and J. Fayard, "Reduction of Nitric Oxide by Soot in
Combustion Products". Proceedings of Fifth Members Conference, IFRF,
May 1978.
59
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WEIGHT Z NITROGEN IN FUEL (OAF)
Figure 1. Conversion of Fuel Nitrogen to NOX for Various Fuels
60
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300
5200
100
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hi Residual 011s
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Figure 2. Minimum NO Emissions Obtained Under Staged Combustion
Conditions for Various Fuels in a Bench-Scale Reactor
61
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MEASUREMENT SYSTEM
ASSESSMENT/DEVELOPMENT
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NUMERICAL MODEL
DEVELOPMENT
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THERMAL
DECOMPOSITION
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Figure 3. Heterogeneous Processes — Project Organization
62
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Figure 4. Composite Plot Showing the Volatility of Convertible Fuel
Nitrogen for Several Fuels as Measured by Axworthy
63
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HeNe ALIGNMENT LASER
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Figure 5. Holographic System Layout Used by Trolinger
-------
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TRANSPORT PROCESSES AND NUMERICAL MODEL DEVELOPMENT
- FCR PROGRAM ELEMENTS
By:
T. J. Tyson, M. P. Heap, C. J. Kau and T. L. Corley
Energy and Environmental Research Corporation
Irvine, California
67
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SECTION 1
INTRODUCTION
The FCR program has two major objectives. These are:
• To provide guidance to development programs concerned with
the application of low NOX combustion systems to stationary
sources.
• To gain insight into the fundamental phenomena controlling
the production of NOX in these devices in order to define
potential advanced control techniques.
One major aspect of the program involves the presentation of basic informa-
tion in such a way as to be of the most benefit to the development engineer.
This information may be transferred directly or in the form of a model which
can be used as a design tool, thereby cutting the cost and delay time asso-
ciated with empirical development programs.
Two fuels, coal and residual oils, when burned in large turbulent dif-
fusion flames confined by relatively cold walls produce the major fraction
of NO,, emissions from stationary combustion sources. Two previous papers have
X
discussed the dominant homogeneous and heterogeneous kinetic processes asso-
ciated with the production of nitric oxide in these combustion systems. How-
ever, these papers did not consider the detailed physics involved in the
turbulent mixing process associated with fuel/air contacting in real com-
bustors. This paper discusses two other elements of the FCR program; those
concerned with numerical model development, and transport processes which
serve the key function of synthesizing information generated in the other
program elements in order to provide an understanding of the basic mechanisms
limiting NOX formation in practical combustion devices.
In the FCR program elements concerned with homogeneous kinetics and
heterogeneous processes the dominant physical and chemical mechanisms perti-
nent to NOX production during the combustion of clouds of oil droplets or
68
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coal particles will be defined. Several experiments have been planned which,
in conjunction with the development of numerical models, will provide a pre-
dictive capability capable of describing NOX production in simple reactor
systems. Two of these programs are concerned with solid and liquid fuels,
and were described in an earlier paper. Two other experimental programs,
one being carried out by Myerson at Exxon and the other by Clark at EER,
are directed towards the generation of data which will allow the verification
of an adequate kinetic mechanism capable of describing NOX production from
simple fuel nitrogen compounds during the combustion of hydrocarbon fuels.
This predictive capability will be refined and verified by comparison with
measurements made in these simple combustion reactors. Once confidence has
been established in the predictive capability, it can be used to analyze the
behavior of staged combustion reactors in a rational and comprehensive search
for those reactor combinations which yield the lower limit of NOX emission
set by the basic physics and chemistry of fossil fuel combustion.
Simple zero- and one-dimensional reactors do not completely reflect the
detailed physics and chemistry associated with turbulent diffusion flames
burning in real furnaces. Consequently, an additional effort has been planned
which will parallel the reactor studies and thoroughly characterize turbulent
diffusion flame phenomena pertinent to NOX formation and destruction. Two
general classes of turbulent diffusion flames can be recognized; those which
involve rapid fuel/air mixing and are dominated by near-field behavior. The
second group of turbulent diffusion flames are far-field dominated and can be
described as long coaxial jet flames. Several tasks have been initiated in the
FCR program which are directed towards understanding the basic turbulent
diffusion layer structure in these general flame types. These investigations
are concerned with particle transport, both ballistic and turbulent, macro-
scale turbulent transport of energy and matter, the persistence of coherent
structures in large-scale flames, and the detailed processes occurring within
these coherent structures.
Once the capability has been developed to model the microscale behavior
of oil droplets and coal particles, and after verifying the model by compari-
son of prediction and observations, it is appropriate to use this model in a
69
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search for lower bounds on NOX emissions dictated by the basic physics of
turbulent transport. The model will aid the understanding of NOX production
and destruction in basic flame elements such as turbulent shear layers, well-
backmixed zones, and plug flow zones. This understanding can then be trans-
ferred to a modular model capable of describing all the complexities of the
fuel/air contacting processes in turbulent diffusion flames The generation
of experimental data to allow this modular model to be developed represents
a major subtask of the transport processes program element, and focuses on
the macroscale flame behavior in an attempt to establish how burner combustion
chamber designs and operating parameters affect the manner in which diffusion
zones and well-mixed zones are established and interact. Once the gross
features of the flow field have been defined the production and destruction
of pollutants on a microscale can be analyzed in an overlay fashion. Having
synthesized the physical and chemical processes associated with NOX production
and destruction with the capability to describe the mass transfer in combus-
tion systems, this model can be used to establish the scaling characteristics
of low NOX devices. The definition of scaling criteria represents one of the
most important goals of the FCR program, and provides the major driving force
towards the description of NOX production in two-phase turbulent diffusion
flames by a hierarchy of models. It should be recognized that in the near-
term these models will contain many empirical subelements. However, their
modular nature will allow for a more complete mathematical description as the
relevant physical and chemical phenomena are defined and quantified.
It is readily apparent that both the development of an understanding of
transport processes and the development of numerical models play an important
role in the achievement of the FCR program goals. Not only do they provide
a predictive capability, they also establish a rationale whereby the effective-
ness of NOX control techniques can be compared against that expected from the
lower bounds set by the various physical and chemical constraints. In addi-
tion, the development of numerical models provides a tool with which to extract
the maximum amount of information from the various experimental programs asso-
ciated with homogeneous kinetics and heterogeneous processes program elements
of the FCR program.
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SECTION 2
MODELING OF SIMPLE REACTOR SYSTEMS
Idealized reactor systems offer the opportunity to examine the physics
and chemistry of pollutant formation from fossil fuels under two extreme
conditions. A well-stirred reactor is the extreme of the backmixed system;
one reactant composition and temperature characterizing the total system.
In the well-stirred reactor there is a distribution of reactant lifetimes
whereas in the other idealized reactor system a plug flow reactor all
reactants have identical residence times. Three investigations have been
planned to study both gaseous and heterogeneous systems under well-stirred
conditions. The existence of a numerical model offers the maximum oppor-
tunity to extract information from these experimental investigations.
GAS PHASE REACTORS
Current activities in this area include:
— analysis of experimental data,
— development of a screening methodology and reaction mechanism
analysis,
— exploratory numerical studies for planning purposes.
One basic goal of the homogeneous kinetic program element is the
validation of a kinetic mechanism capable of describing the conversion of
fuel nitrogen compounds to either XN specie (NO, NH3, HCN) or N2 during the
combustion of hydrocarbon fuels. The development of such a mechanism requires
both a numerical modeling capability and experimental data with which to
verify the kinetic mechanism. In the homogeneous kinetic program element two
investigations are being carried out which will provide the necessary data.
The current reaction set for methane/air combustion was developed without a
knowledge of the total XN concentration in rich combustion systems. Myerson
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is currently providing data on the generation of nitrogenous species from
ammonia in a well-stirred reactor fired by methane, propane and ethylene
for various initial ammonia concentrations and reactor temperatures. A high
temperature plug flow reactor is being used to generate time-resolved pro-
files under isothermal conditions to examine the decay of XN species in fuel-
rich mixtures under controlled isothermal conditions. The EER kinetics
analysis code is being used to determine the key reaction path associated
with fuel nitrogen conversion in these simple reactors. The code has a
sensitivity analysis capability which allows the influence of variations in
reaction rate upon specie production or energy release to be assessed. The
code has also been used to evaluate the current methane/air mechanism by
comparing ignition times against those measured in shock tube studies.
Although the methane/air reaction set has not been completely validated,
it has been used in a series of numerical investigations as an aid in the
planning of future work. These exploratory studies include the following.
— An examination of the influence of quench rate and reactant
stoichiometry on XN decay during staged combustion.
— An evaluation of the use of artificial oxidants for determination
of fuel nitrogen conversion. Experiments have been carried out
using argon, oxygen, carbon dioxide mixtures in an attempt to
eliminate thermal NO production, and thereby determine fuel
nitrogen conversion directly. Numerical studies suggest that
the use of these oxidants affects fuel nitrogen conversion,
particularly under fuel-rich conditions.
— An examination of the effect of initial fuel nitrogen compound
on the formation of XN specie.
— The interaction of SX and NX specie during fuel-rich combustion.
— A preliminary analysis of the influence of higher hydrocarbons
on fuel nitrogen conversion.
— The development of a preliminary reaction set for acetylene as
the hydrocarbon gas.
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— Analysis of microscale unmixedness in stirred reactors. One
potential problem associated with the use of well-stirred reactors
is the degree of mixedness and a series of numerical investiga-
tions have been carried out to assess the effect of this unmixed-
ness on the performance of a stirred reactor.
HETEROGENEOUS REACTORS
The previous paper described the projects being carried out in the
heterogeneous process element of the FCR program. Two of these projects
involved experimental investigations of the fate of fuel nitrogen in both
solid and liquid fuels burning in well-backmixed conditions. A general
heterogeneous well-stirred plug flow model is currently being developed to
aid in the interpretation of these results. The model uses the gas phase
model with a series of subelements which describe the evolution of hydro-
carbon gases and fuel nitrogen specie from the coal particles or liquid
droplets, as well as a heterogeneous heat release model. Naturally, in
its current stage the model includes considerable empiricism. However,
information being generated on the thermal decomposition of both coal and
liquid fuels, char nitrogen oxidation, and the reduction of NO by solids
will be fed into the model as it becomes available.
The modeling of the fate of fuel nitrogen in heterogeneous reactors
requires information on the following:
— the dependence of devolatilization characteristics on the
particle temperature and gaseous environment.
— the molecular consistency of the devolatilization products and
both the rate and order in which they are evolved.
— particle droplet heat up transients and temperature overshoots
as dictated by heterogeneous reactions and energy release in
the diffusion layer surrounding the particle/droplet.
- the division of fuel nitrogen between heavy molecular weight
gaseous components and the char, and the kinetics of char
nitrogen conversion.
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— particle/droplet relative Reynolds number effects on all transport
processes.
Once the model is available it can be used to examine the influence of those
processes listed above on the fate of fuel nitrogen, as well as providing a
basis to define under which conditions fuel nitrogen conversion to NO is
minimized.
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SECTION 3
FLUID MECHANICS AND MODELING OF DIFFUSION FLAMES
Pulverized coal and residual fuel oil are burned in turbulent diffusion
flames (i.e., the fuel and oxidant are injected into the combustion chamber
separately) and the rate of heat release is normally controlled by the rate
of fuel oxidant mixing. Combustion and pollutant formation is complicated
by the turbulent mixing process, and currently there does not exist an ade-
quate model for gaseous systems let alone one involving solid or liquid fuels.
One aspect of the approach being taken in the FCR program is to examine the
influence of various types of molecular diffusion controlled reaction zones
on pollutant formation since these could represent the full range of reaction
zones likely to be embedded within real turbulent diffusion flames. In addi-
tion, the understanding gained from studying simple flame systems provides
validation of the kinetic mechanism under conditions that are very different
from those used in its development.
MOLECULAR DIFFUSION FLAMES
A generalized diffusion kinetics analysis code has been developed which
allows several flame systems to be modeled which involved molecular diffusion.
The utility of such models is associated with the computational time required
to carry out meaningful calculations. The current code utilizes operator
splitting techniques for those situations which are path dependent, and fully
implicit techniques involving the inversion of block tridiagonal matrices for
conditions which have an asymptotic solution. The generalized code includes
the following options:
— strained flames
— steady state particle/droplet flames
- transient confined particle/droplet diffusion flames
— transient spherical gas pockets
— free shear layer flames
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— coaxial jet flames
— flat premixed flames
The code has been used to date to examine flat premixed flames, coaxial
jet flames, and strained opposed jet diffusion flames. The strained flame
provides one link between the modeling being carried out on molecular dif-
fusion flames and turbulent diffusion flames, since the coherent flame
structure model assumes that reaction takes place in diffusion layers
separating the fuel and the oxidant. Computations have been carried out on
the effect of strain rate on flame thickness, flame temperature, thermal
NO production and fuel NO production from ammonia. These computations are
currently being used by Broadwell and Marble in a model of NO production in
a simple turbulent diffusion flame.
DIFFUSION EFFECTS IN PARTICLE/DROPLET COMBUSTION
The conversion of fuel nitrogen to NO in coal and oil flames may depend
upon diffusion controlled processes which occur during thermal decomposition,
and are associated with the physical effects of particle droplet heating.
Experimental data on fuel nitrogen conversion in premixed fuel-lean coal
flames suggests that approximately 30 percent of the total fuel nitrogen is
converted to NO. Taking account of the division of fuel nitrogen between
gas and char components, conversion on the order of 60 percent of the
volatile component can be expected. These are similar to conversions mea-
sured with liquid fuels of similar nitrogen contents. However, in a fuel-
lean premixed gaseous system, fuel nitrogen conversions on the order of
90 percent would be expected. Therefore, any model which assumes that
nitrogenous species released from the particle/droplet are immediately com-
pletely mixed with the surrounding bulk gases will provide conversion rates
which are higher than those encountered in practice. Thus, reaction in a
diffusion-controlled layer might well be a necessary submodel for hetero-
geneous systems.
Nitrogen species may be driven from a coal particle as a jet, or feed
some zone around the particle which then reacts in a layer surrounding the
particle rather than in the bulk gas phase. Numerical experiments are
planned to compare fuel nitrogen conversion in diffusion layers of these
types (i.e., mantle, wake or envelope) to that which would occur in the bulk
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gas phase. Reaction in the diffusion layer will also control particle
temperatures which may yield particle temperatures well in excess of the
mean bulk flow and thus have a strong influence on devolatilization rates.
FLUID MECHANICS AND MODELING OF TURBULENT DIFFUSION FLAMES
Broadwell and Marble are developing a coherent flame structure model
for gaseous turbulent diffusion flames. In addition there are several
experimental studies either planned or in progress. They will provide
information which will later be fed into a model of turbulent diffusion
flames. The tasks currently underway are:
• Wendt and Hahn at the University of Arizona are measuring the
conversion of ammonia to NO in a methane/air opposed jet dif-
fusion flame representative of strained flamelets which may
dominate the internal behavior of turbulent flames.
• Vranos at UTRC is currently investigating the combustion of
heavy oil droplets in a free shear layer separating oxidant
from high temperature combustion products.
• A study will be initiated shortly with IBM to use high-speed
cinematography to ascertain whether coherent structures play
a significant role in large-scale turbulent diffusion flames.
A subcontract effort is planned to characterize in detail long turbulent dif-
fusion flames of both pulverized coal and heavy fuel oil at various scales.
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SECTION 4
FLUID MECHANICS AND MODELING OF FLOW FIELD
AND FUEL/AIR CONTACTING IN LARGE COMBUSTORS
- MACROSCOPIC BEHAVIOR
Low NO combustion systems for pulverized coal and heavy oil flames
X
can be classified into two major groups:
• Low NO burner designs. The objective of the development of
X
low NO burners is to provide a burner system which will be
2t
accommodated by existing combustion chamber designs. Thus, its
implementation will require the minimum degree of combustion
chamber modification.
• Divided chamber systems. The advanced NO control techniques
(i.e., those capable of achieving emission levels on the order
of 20 ppm) will involve a completely zoned combustion chamber
which will allow the control of temperature and optimize XN
decay in a rich section, as well as minimizing NO formation
during the second stage combustion process.
The FCR program is currently planning investigations which will aid in the
development of these systems. The program involves a parallel experi-
mental and modeling task whose goal is to provide a model which links
burner combustion chamber design and operational parameters with flow
field characteristics such as the size and strength of recirculation
zones, the rate of fuel/air mixing, the influence of energy release on
flow patterns, etc. This model can then be used in conjunction with the
other flame element models to provide a tool which will be used to suggest
control strategies.
Four basic flow field types have been identified. These include:
• Intensely swirl-stabilized: recirculation zone closed on the
centerline, near-field dominated, energy release primarily in
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the free shear layer enclosing the recirculation zone. Initial
fuel deposition can be distributed between the recirculation zone
and the outer shear layer.
• Weakly swirl-stabilized: recirculation zone toroidal and open
on the centerline with high momentum fuel passing downstream
through the recirculation zone. Flow is dominated by the far-
field behavior with energy release distributed well-downstream.
Some fuel is initially deposited or swept into the recirculation
zone to provide stability.
• Nonswirling long flames: stability provided by furnace-scale
recirculation and the impingement of neighboring flames on the
flame root.
• Divided chamber physically staged burner: particular attention
here is given to modeling the interstage or secondary stage
mixing behavior (the desire here is to minimize thermal NO forma-
tion and NO formed by oxidation of nitrogen intermediates).
The initial experimental task will concentrate upon the near-field of
an intensely swirl-stabilized flame and the influence of the following
independent parameters on the flow field will- be ascertained:
- radial distribution of swirl and axial velocities at the burner
throat;
— the length-to-diameter ratio and the area ratio of the burner
divergent section;
— the degree of burner confinement or proximity to neighboring
burners; and
- the fuel dispersion and resulting energy release distribution
(this involves the deposition of fuel in particular parts of
the flow field and will be accomplished by the use of multiple
fuel injection ports or fuel dispersion rakes).
In addition to conventional flame diagnostics, use will be made of stimulus
response tracer techniques to assist in mapping the flow field and deter-
mining turbulent transport intensity.
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The parallel model development effort will concentrate on intensely
swirl-stabilized systems. Weakly stabilized systems will be modeled by a
modified version of a coaxial long turbulent diffusion flame code. Cur-
rently a program is underway at TRW where Fendell is evaluating available
elliptic codes for use in flow field prediction.
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SECTION 5
SUMMARY
This paper has reviewed the effort which is currently underway or
planned in the FCR program elements concerned with numerical model develop-
ment and transport processes. One key feature of the overall approach is
the use of limit-case models to evaluate the lower bounds on NO production
X
which are set by practical constraints. Examples of such limit-case studies
are provided by the use of simple gas phase reactors with a suitable reaction
set in order to evaluate the optimum time/temperature stoichiometry history
of staged combustion systems. Figure 1 provides an example of one such
study. The decay of XN specie in a fuel-rich combustor is kinetically-limited
and the optimum combustor will be a compromise between volume and pollutant
emissions. Thus it is necessary to maximize the rate of XN decay in a fuel-
rich zone. The example shown in Figure 1 illustrates how distributed air
addition to a fuel-rich region can maximize this decay rate. Further calcu-
lations of this type are planned involving heterogeneous as well as gaseous
systems.
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ADDITION
PRIMARY:
SECONDARY:
TERTIARY:
(CtVNH3) + AIR - 1Z NH3 IN FUEL
30 10 50 60 70
PLUG FLOW RESIDENCE TIME, MS
Figure 1. Decay Rate of Total XN Species in Isothermal Plug Flow
Reactor as a Function of Stoichiometry and Temperature
Showing that Distributed Addition Maximizes Decay Rate
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SESSION VII
ENVIRONMENTAL ASSESSMENT
WADE H. PONDER
SESSION CHAIRMAN
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SURVEY OF PROJECTS CONCERNING CONVENTIONAL
COMBUSTION ENVIRONMENTAL ASSESSMENTS
by
W. E. Thompson
November 1978
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ABSTRACT
The work reported on is part of the overall Conventional Combustion
Environmental Assessment (CCEA) program being conducted by EPA. A nationwide
survey has been made to identify projects that are relative to one or more of
the environmental assessment elements of the methodology recently developed.
The information necessary to compare CCEA-related projects has been defined.
Comprehensive forms have been devised to elicit the information. Literature
searches were carried out for the years 1970 to 1976. Institutions doing
relevant work were identified. Research identified centered on kinds of
pollutants emitted and their control and impact. The record of projects
sponsored by EPA's Industrial Environmental Research Laboratory/Research
Triangle Park (IERL/RTP) was examined. Extensive research is being conducted
by IERL/RTP on emissions characterization, control processes (SO , NO ,
particulates), and economics.
Major sources surveyed for governmental research were: the Interagency
Energy-Environment Research and Development Program Report, in which the
computer search turned up 1,000 projects of which 246 were deemed relevant,
and the Inventory of Federal Energy-Related Environment and Safety Research,
from which 150 projects were selected from the 2,500 citations.
Further information on what is being done and by whom was obtained by
attending national technical meetings and by visiting organizations for techni-
cal discussions. Present work centers on the development of a computerized
system for the storage of the information so that it may be retrieved in a
form that will facilitate management decisions.
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This is part of the overall CCEA program being conducted by EPA's Indus-
trial Environmental Research Laboratory/Research Triangle Park (IERL/RTP).
The program is limited to studies relating to stationary conventional
combustion processes.
From the beginning of the program, one of the major questions was:
What constitutes an "environmental assessment"? This question has been
answered by the methodologies developed by the Energy Assessment and
Control Division of IERL/RTP and more particularly for the CCEA program by
the Mitre Corporation. The Mitre methodology, shown in figure 1, contains
approximately 70 elements used as the basis for classifying project activity.
In order to carry out an environmental assessment analysis on CCEA-
related projects, information on the following subjects is necessary:
1. Fuel characterization,
2. Combustion process,
3. Effluent characterization,
4. Control techniques evaluation,
5. Health and ecological evaluation,
6. Quantification of pollution impacts, and
7. Environmental goals and objectives comparisons.
Very early in the course of work on this assignment, discussions were
held with personnel of the Process Measurements Branch of the Industrial
Processes Division of IER1/RTP. Their position was that projects requiring
environmental assessment data could be compared for overlap or gaps only by
a detailed analysis which included information on:
1. The specific source types being considered,
2. The points in the process at which samples were being taken,
3. The sampling procedures used, and
4. The analytical procedures used.
In order to elicit the information needed, a comprehensive set of
forms have been developed by RTI. The forms cover the following details:
1. Project administrative data,
2. CCEA element checklist,
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3. CCEA burner/fuel category identification,
4. Identification of sampling and analysis techniques,
5. Pollutant control methods checklist,
6. Health effects methods checklist, and
7. Ecological effects checklist.
A major portion of the Research Triangle Institute (RTI) work assignment
was to obtain information with as much detail as possible on activities
sponsored by government, industry, universities, and other organizations
related to the environmental assessment of conventional combustion processes.
This information was to be analyzed to determine its significance relative
to the CCEA program. The effort was structured to obtain information on a
broad nationwide basis on the scope of CCEA-related projects. It should be
emphasized here that the effort was aimed at gathering information on the
type of projects and the organization carrying them out. No numerical data
or research results were gathered or evaluated. In other words, the effort
was aimed at descriptions of "who is doing what?"
The information was collected by various methods, e.g., telephone
contacts, a computer data base literature search, published project inventory
data, contractor reports, information from technical symposia, and discussions
with researchers at their respective institutions.
Initially a number of telephone calls were made to organizations that,
based on RTI's past experience, were known to be performing CCEA task-
related work. However, telephone calls were found to be a poor method of
eliciting any details.
Literature searches were carried out for RTI by the North Carolina
Science and Technology Research Center (a NASA Industrial Applications
Center). The information produced was then evaluated by RTI technical
personnel for relevance. The data files searched for published CCEA
research projects are shown in table I. The search was keyed on air
pollution associated with fuel combustion, and sought articles and reports
published from 1970 to 1976.
From these citations several items of interest were distilled. The
first was a long list of domestic organizations involved in such research.
The next item of interest was the subjects addressed in the research. These
were categorized by major assessment elements as shown in table II.
-------
It should be pointed out that the sum of the right-hand column of table II
exceeds 477 because many of the articles and reports dealt with several
assessment element topics. Discussions on pollution control received the
largest attention, with the identification of pollutants and determination
of pollutant loadings coming next. Fuel and source characterization were
next.
The third item of interest was the comparison of activity in the
sectors addressed over the period of the survey. This was obtained by a
census of articles by sectors/media: utility/air, industrial/air, and
residential/air. The commercial institutional sector did not appear to be
covered at all. A very large amount of activity was in the relationship of
pollutants and control methods for the emissions associated with various
fuel types. The results of this crude census are shown in figure 2. In
this figure it may be seen that fuel-related CCEA research has been consis-
tently strong. Research reported on air emissions and controls for utilities
peaked in 1973 and 1974. Research on air emissions and controls for indus-
trial sources has overtaken and passed that for utilities. Compared to the
other categories, research on residential source emissions and controls has
been low key.
We may conclude from this study that from 1970 to 1976 a large number
of domestic organizations were involved in research on what kinds of pollu-
tants are emitted, how they can be controlled, and what their impacts might
be. Further, it seems that the tempo of the research has increased as
public and institutional awareness has increased and as Federal and State
pollution regulations have been promulgated.
A well-defined data base for CCEA activity is provided by the records
of projects sponsored by EPA's Industrial Environmental Research Laboratory.
Up until mid-1975, IERL program activities were primarily directed to
process characterization and pollution control development directed to air
pollution from stationary sources. Following the reorganization of EPA's
Office of Research and Development (ORD) on June 10, 1975, lERL's pollution
control activities began to span a wider range. A multimedia approach was
taken, which was concerned with pollution in air, water, solid waste,
thermal discharge, and energy conservation. In addition, cooperative
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efforts with other EPA laboratories and other Federal agencies have been
undertaken to build programs that consider and include all aspects of
environmental assessment in order to make explicit the alternative approaches
in balancing the demands of minimal environmental quality degradation,
economic constraints, and energy constraints. This growth into a broader
outlook can be followed by tracing the topics dealt with by IERL project
reports. The projects are organized in the following categories:
1. Reports on emissions characterization, methodology and measure-
ments (75 projects),
2. Reports on S02 control processes for conventional combustion
sources (110 projects),
3. Reports on NO control processes for conventional combustion
sources (35 projects),
4. Reports on particulate matter controls for conventional com-
bustion sources (60 projects), and
5. Reports on economic, energy, and resource recovery or conser-
vation factors (35 projects).
Another important source of information is the Interagency Energy-
Environment Research and Development Program Report, published under the
guidance of ORD/EPA. For FY1975 and FY1976, these program abstracts were
published in bound volumes. These reports were categorized into pollutant
characterization, measurement and monitoring, environmental transport and
fate, health effects, ecological effects, integrated assessment, and nine
classes of control technology. This arrangement facilitated analysis.
However, for FY1977 the information was entered on a computer but not
published. Computer searching of the system was complicated by the fact
that the ORD Information System report listed approximately 6,000 key
words. In order to make a search, we limited the number of key words used
to 25. Approximately 1,000 projects were received on the computer printouts.
Upon analysis, 246 were deemed to be relevant to the CCEA program. The
breakdown is shown in table III.
The system contains project-level descriptions of nearly all of the
$100 million in research and development funded by the EPA-coordinated
Interagency and Energy-Environment R&D program.
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An advantage of the published abstracts was that they were grouped by
agencies. Project descriptions are coded from Notice of Research Projects
forms prepared by the appropriate laboratories and agencies using the
Smithsonian Science Information Exchange format. This data base is limited
to five agencies: EPA, the Energy Research and Development Administration
(ERDA), the Department of the Interior, the Tennessee Valley Authority, and
the Department of Agriculture.
Perhaps the most important single source of information is the Inventory
of Federal Energy-Related Environment and Safety Research, the so-called
ERDA-DOE Inventory. The purpose of the inventory is to provide a data base
for overviews of federally funded, energy-related environment and safety
research projects. The inventory is designed to be used to assist planning
for future research by aiding in the determination of the adequacy of
current environmental, health, and safety research programs to meet the
needs of developing energy technology. The Energy Reorganization Act of
1974, PL93-438, authorizes the ERDA administrator to establish programs to
minimize the adverse environmental effects of energy development and use.
It further directs that these programs will use research and developmental
efforts supported by other Federal agencies in a cooperative manner to
avoid unnecessary duplication. A comprehensive plan was required to be
submitted to Congress by the Federal Non-Nuclear Energy Research and Develop-
ment Act of 1974, PL93-577, Section 6. The inventory complies with these
requirements. Fourteen Federal agencies provided information for the
inventory in response to form 294, which was approved by the Office of
Management and Budget. Table IV gives the name of each agency, the number
of projects for each agency, and the FY1976 funding level for research in
biomedical and environmental research, environmental control technology,
and operational safety for this particular fiscal year. About 84 percent
of the total Federal funding is represented by the sum of the budgets of
ERDA, the Nuclear Regulatory Commission, EPA, and the Department of Commerce.
The field of biomedical and environmental research is divided into five
categories. These are:
1. Characterization, measurement, and monitoring;
2. Environmental transport, physical and chemical processes, and
effects;
3. Health effects;
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4. Ecological processes and effects; and
5. Integrated assessment.
Table V shows a technology funding distribution for each of these
categories. Table VI shows the breakdown of funding by technology areas for
projects on environmental control technology. Note that EPA dominates the
fossil fuel area and ERDA the nuclear area. The inventory summarizes
approximately 2,500 projects, of which approximately 150 were identified as
relevant in our survey of the 1976 inventory. The FY1977 inventory is now
being surveyed.
A visit was made to the Electric Power Research Institute (EPRI) where
discussions were held with a number of technical personnel. These discussions
provided an overview of the extensive research programs being carried out
under EPRI funding. Some idea of the magnitude of this effort can be
obtained by considering the proposed 1977-1981 EPRI budget, shown in table
VII. For example, the proposed combined expenditures in fossil fuel controls
and environmental assessment over the 5-year period amount to about $143
million for 13 percent of the entire EPRI budget for the period. Since our
visit, EPRI has provided us with numerous projects abstracts and planning
documents. An analysis was made of the entire EPRI research program in
terms of projects relevant to the CCEA program.
We have found attendance at symposia and meetings to be an excellent
low-cost method of adding to our program information data bank. Some of
the most valuable appeared to be:
1. EPA Stationary Source Combustion Symposia;
2. EPA Symposia on Flue Gas Desulfurization;
3. EPRI Symposia; and
4. Air Pollution Control Association meetings, both national and
regional.
The most detailed information was gathered by visits to various
organizations involved in combustion research for direct discussions
with the researchers. This yields very satisfactory information. Unfortun-
ately, this is the most expensive method. In most cases, however, the
results obtained were satisfactory. For example, detailed information was
gathered on the entire program at Pennsylvania State University, the
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Princeton University combustion research operation, combustion research at
the University of California at Berkeley, and the well-known analytical
work being conducted at the University of California, Livermore.
All of the mass of data collected has been reduced to tables giving
project title, organization, funding organization, budget, and other
administrative information. In addition, a great number of abstracts of
projects have been presented in special reports. However, it is doubtful
that so much information can be readily prepared for analysis of such
things as overlaps and gaps in programs. Therefore, we are at present
engaged in a study of the feasibility of using a computer storage and
retrieval and display system. This is being designed to give the greatest
possible flexibility for management information needs that we can design.
The problem of using all of the information on projects scattered through-
out a great number of organizations in order to yield a true environmental
assessment of conventional combustion processes is yet to be solved.
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COMBUSTION PROCESS TECHNOLOGY
CHARACTERISTICS
• Process itm-of-the-in
• Process Kommin
• Energy efficiency
FUELS CHARACTERIZATION
Type tftd tourct
Physicel cnirecterittici
Chimicil chorKteristics
Energy content
Full hindlint
AviillbHity ol hull
DOSE RESPONSE DATA
Threshold limit vriwi (TIVI
Lilt shortening chronic tipoiufi
Cinctt irxl leukemii
Respiratory Hum
INPUT OUTPUT CHARACTERIZATION
• MMeriil bllenu
• Stoedy-ttm. ttinmnt, iml
milhinction penguin
li
ECOLOGICAL IMPACTS
Ecology rallied impocts
All, mter. md lind quelit,
Ouontlfied radio dognditior
ICOMIUSTION PROCESSES AND I
EFFLUENT CHAHACTERIZATION I
TRANSPORT. TRANSFORMATION.
FATE MODELS
• Meteonlogicol >nd Nydtol«|k din
• Model development
• E iposura Iml ahuliMin
• Transloimetion chemistry
STATUTORY CONSTRAINTS
• Ftdml/iuti uindirdi md ngglniont
• Retouch dm b>» lot mndirdi
DEVELOPMENT OF SAMPLING AND
ANALYSIS TECHNIQUES
• Sampling tichniqutt
• Anilyiii tKhnirtmi
• Bloiuiy tichniquai
CONTROL TECHNOLOGY DEVELOPMENT
RECOMMENDATIONS
• Control ttchnology modificitiont
• Dointififd R&O nmfs
• Critirii lor priorities
• Time fnmi
FIELD TESTS AND SURVEYS
• Control lyitimi tntimj
• Combintion proens testing
• Comprehensive west! streim
chiricteriietion
- Level 1
- Lent 2
- Level 3
1 HEALTH AND ECOLOGICAL
IMPACTS IDENTIFICATION
EMISSION OF AMBIENT
LEVEL COALS
Permissible medii concentration
Critirii for estlblishing priorities
Control technology limits
MATE
EPIDEMIOLOGICALDATA
• IndlHUy tilitid h«lth dm
• Inctmtd mofbidity ind mom
itv
IIOASSAV DATA
Stindard bionuy ttchniqutf
lioimy crittrii
Control proem ttrMfli brooHiy
RONMENTALGOALSANDl
OBJECTIVES DEVELOPMENT I
AMBIENT POLLUTANT LEVELS
• Dm Colliction ind inJuitioit
SOCIAL/ECONOMIC/POLITICAL/
INSTITUTIONAL CONSIDERATIONS
• NonpollutintimpMtgoali
(imrgy. uciil, oconomic, itc.)
• Quintiftnl nonpollunnt impKts
• Siting crittrii
• Criticil mtteriili impKts
MAYBE
CONTROL STRATEGY ENVIRONMENTAL
IMPACTS
• Wimdkpoul option
• Sicondiry tnvironffllrrlil impKb
• Cron-modio impictt
CONTROL ALTERNATIVES
• Add-on dnicn
• Comhiition modificltiofl
• Foil milch/mining
COMBUSTION PROCESS
USE PROJECTIONS
Curnnt mirklt lill
Futuri mirklt proitcrjom
ESS
S
om
ojictiont
1
t
NO
TOTAL
LOADC
• Proce
• Othl
• Nltu
1
Environmintil Aitmmtnt
Procidun Complitid for
this Combvition Proem
Otlw lources (aiding
Nitunl background
ALTERNATIVE CONTROL
STRATEGY EVALUATION
Figure 1
CONTROL STRATEGY EVALUATION
RAD Kill lysttm
Otmomtration Kilt lyttim
Economki
Enirgy nquinmintt'
Pollutint nmovtl ifficiMcy
Opmtionl milibiMy
Sourct iralym modoh ISAM'i)
MAGNITUDE OF
POLLUTION IMPACTS
POLLUTANT PRIORITY
RANKING
Totilpollutintloid
Olgrn of huird (smrhy indwell)
STANDARDS DEVELOPMENT
RECOMMENDATIONS
• Stindirdt modlficitiom
• Stindirdi dnttopmitn
• Critirii for prtorittti
• Tiim frarnt
REGIONAL GEOGRAPHIC
DATA
Dimognphic & lind uie pittirm & tnnds
Hydrology ind mittorology
SYNERGISTIC > MULTIMEDIA IMPACTS
• Multimidii pollunnt diitribution loidt
• Adttitivt, traniformMion, Ind enhincemint
ifflCU
-------
73
74
75
76
Figure 2. Results of citation census for CPA research in categories of utility/air (U/A),
industry/air (I/A), residential/air, (R/A), and pollutants and controls related
to various fuel types (F).
95
-------
TABLE I. DATA FILES SEARCHED FOR PAST CPA RESEARCH ACTIVITY
Data Base Name
Subject and Source
Coverage Number of
From Citations
Engineering Index
(compendex)
Energy Data Base
Pollution
Smithsonian Science
Information Exchange
Worldwide engineering
literature
(3,500 publications)
Complete energy
information (ERDA)
Pollution and environment
(pollution abstracts)
Research projects in
progress; emphasizes
federally funded projects
and includes many
privately funded projects
1970 500,000
1974
1970
100,000
37,700
1966 200,000
96
-------
TABLE II. DISTRIBUTION OF ARTICLES AND REPORTS BY ASSESSMENT ELEMENT CATEGORY
Number of Articles
Assessment Element and Reports
Source characterization 70
Determination of material inputs 60
Identification of pollutants 93
Identification of media for each pollutant 11
Determination of pollutant loadings 83
Fugitive emission analysis 4
Operating parameter sensitivity analysis 71
Controls 342
Combined effects assessment 3
Cross-media effects assessment 1
Environmental conversion assessment 5
(secondary pollutants)
Health effects 1
Ecological effects 15
Energy analysis 28
Economic analysis 28
97
-------
TABLE III. RELEVANT CCEA PROGRAM PROJECTS
Category No. of Projects
Fuels 9
Sampling and Analysis 62
Emissions—Effluents 26
Controls—General 3
Controls—Particulates 20
Controls—NO 12
x
Controls—S02 12
Transport and Fate 23
Health 49
Ecology 26
Integrated Assessment 4
98
-------
TABLE IV. FEDERAL AGENCY RESPONSES
No. of Projects Funding by Agency
Agency Reported ($ in millions)
Department of Agriculture 7 7.6
Department of Commerce 93 41.0
Department of Defense 3 1.4
Department of Health, Education,
and Welfare 263 22.6
Department of Housing and
Urban Development 1 <0.05
Department of the Interior 80 25.9
Department of Transportation 9 .4
Environmental Protection Agency 305 63.0
Energy Research and Development
Administration 1,467 197.5
Federal Energy Administration 20 1.7
National Science Foundation 18 1.2
National Aeronautics and Space
Administration 5 1.3
Nuclear Regulatory Commission 200 . 77.5
Tennessee Valley Authority 65 11-8
Total 2,536 452.9
99
-------
TABLE V. BIOMEDICAL AND ENVIRONMENTAL RESEARCH SUBCATEGORY FUNDING BY FEDERAL AGENCY, FY 1976 ($ in millions)
o
o
Energy Technology
DOA
DOC:
OEA
NBS
NOAA
DOD
HEW:
NIOSH
NIEHS
NCI
HUD
DOI:
FWS
BLM
USGS
RECLAM
BPA
DOT
EPA
ERDA
FEA
NSF/RANN
NASA
NRC
TVA
Characterization,
measurement ,
and monitoring
0.3
1.9
4.3
-
0.9
<0.05
-
0.2
7.4
0.1
<0.05
0.1
5.6
20.8
0.2
0.2
0.2
1.6
1.2
Environmental
transport
0.8
<0.05
8.5
-
<0.05
-
4.2
<0.05
-
1.9
21.3
0.1
0.3
0.2
3.5
1.3
BER Subcategory
Health effects
-
0.1
0.2
-
1.0
13.2
6.7
-
-
<0.05
4.6
78.4
<0.05
<0.05
<0.05
0.6
<0.05
Ecological
effects
1.8
<0.05
19.0
-
0.5
-
2.3
2.5
0.1
<0.05
-
3.9
19.6
0.2
0.3
0.1
0.7
1.9
Integrated
assessment
0.9
0.2
6.3
-
0.1
<0.05
<0.05
3.6
0.3
-
3.1
13.7
1.1
0.2
0.1
1.0
1.5
Total
3.8
0.2
2.0
38.2
-
1.9
13.8
6.7
<0.05
2.5
17.8
0.2
0.4
0.1
19.1
153.8
1.6
1.1
0.6
7.4
5.9
Total
45
42.1
104.8
52.9
32.1
277.1
-------
TABLE VI. ENVIRONMENTAL CONTROL TECHNOLOGY FUNDING (ENERGY TECHNOLOGY BY FEDERAL AGENCY), FY 1976 ($ in millions)
Oil
Fossil and Oil Bio-
Agency general Coal gas shale mass
I)OA 2.9 0.5 - 0.2
DOC:
OF.A -
NBS -
NOAA - - 0.1
DOD 0.1 - - -
HEW:
NIOSH - -
N1EHS - ....
NCI - ....
HUD - -
D01 :
FWS -...--
BLM .....
USGS - 2.8 0.3 0.3
RECLAM - -
BPA - <0.05 <0.05
DOT .....
fiPA 3.5 27.7 3.3 0.8 0.9
KRDA 0.1 2. it 1.1 0.1
FEA - ....
NSF/RANN - -
NASA - 0.2 - <0.05
NRC - ....
TVA 0.8 4.0
Total 7.4 37.6 4.8 1.4 0.9
Technology
Nuclear Geo- Hydro- Conser- Multi- General
general Fission Fusion thermal Solar electric vation tech science Other Total
0.1 ----- - - - - 3.7
-- -- - -- - . .
----- -- ...
<0,05 <0.05 <0.05 - - - 0.2
1.3 - - 1.4
----- -- .-.
----- -. ...
----- -- - . -
-
----- -- -.-
----- -- -..
----- 0.2 - 0.4 0.1 4.1
----- -- ..-
0.1 - - - - 0.1
0.1 - - 0.1
<0.05 - - 0.4 0.4 - 2.6 3.1 0.4 0.7 43.9
30.5 0.7 0.2 0.7 <0.05 - 0.3 0.5 0.2 0.2 36.9
.
<0.05 <0.05
<0.05- - - 0.4 - - 0.7
1.3 <0.05 ... - - - - 1.3
0.1 0.5 - 0.3 <0.05 5.7
31.9 0.7 0.2 1.1 0.4 0.2 4.9 4.1 1.3 1.0 98.1
-------
TABLE VII. EPRI SUMMARY OF PROPOSED PROGRAM PLAN ($ in millions)-
Program
FOSSIL FUEL AND ADVANCED SYSTEMS
Fluidized combustion and coal cleaning
Air quality control
Water quality control and heat rejection
Fossil plant performance and reliability
TOTAL — Fossil fuel power plants
Clean gaseous fuels
Clean liquid and solid fuels
Power generation
Power plant requirements and analysis
TOTAL- -Advanced fossil power systems
Fusion
Solar
Geothermal
TOTAL--New energy resources
Energy storage
Fuel cells and chemical energy conversion
Energy utilization and conservation
technology
TOTAL — Energy management and
utilization technology
TOTAL--FOSSIL FUEL AND ADVANCED SYSTEMS
NUCLEAR POWER
Water reactor system technology
Reliability, availability, and economics
Fuels, waste, and environment
Developing application and technology
TOTAL- -NUCLEAR POWER
ELECTRICAL SYSTEMS
AC transmission
Underground transmission
DC transmission
Distribution
Systems planning, security, and control
Rotating electrical machinery
TOTAL— ELECTRICAL SYSTEMS
ENERGY ANALYSIS AND ENVIRONMENT
Environmental assessment
Demand and conservation
Supply
Systems
Electric utility rate design study
TOTAL—ENERGY ANALYSIS AND ENVIRONMENT
TOTAL FUNDS ALLOCATED
Nonprogrammed expenditure
TOTAL INSTITUTE
1977
4.8
14.3
1.9
2.4
23.4
11.1
14.9
5.8
0.7
32.5
4.7
4.4
2.2
11.3
5.2
9.0
1.0
15.2
82.4
14.8
14.1
8.0
9.1
46.0
7.0
7.5
10.9
5.2
1.9
0.5
33.0
10.4
2.1
3.1
1.5
.8
17.9
179.3
_
179.3
1978
8.1
10.2
2.4
2.8
23.5
9.5
14.8
7.0
1.0
32.3
3.4
3.4
2.0
8.8
7.1
8.5
1.4
17.0
81.6
18.8
16.4
9.0
7.0
51.2
7.5
7.5
4.4
6.4
2.7
2.8
31.3
12.5
2.7
3.8
1.6
.3
20.9
185.0
5.0
190.0
1979
8.8
10.2
2.6
3.0
24.6
10.0
14.5
7.5
1.0
33.0
3.8
3.7
2.0
9.5
9.0
6.7
2.3
18.0
85.1
17.9
16.9
9.7
9.0
53.5
7.9
8.0
3.9
6.7
2.9
3.2
32.6
14.8
2.6
3.7
1.7
—
22.8
194.0
9.0
203.0
1980
9.4
10.4
2.6
4.1
26.5
10.0
14.5
9.5
1.0
35.0
4.3
4.0
2.2
10.5
8.9
6.6
2.5
18.0
90.0
18.0
16.0
10.7
11.8
56.5
8.3
8.4
4.0
7.3
3.1
3.4
34.5
17.0
2.6
3.7
1.7
-
25.0
206.0
28.0
234.0
1981
10.0
10.8
2.7
4.4
27.9
10.0
14.5
10.5
1.0
36.0
4.4
4.3
2.3
11.0
8.2
7.8
3.0
19.0
93.9
17.9
13.9
12.2
15.0
59.0
8.7
8.8
4.2
7.6
3.2
3.5
36.0
20.1
2.6
3.7
1.7
~
28.1
217.0
61.0
278.0
Total
41.1
55.9
12.2
16.8
126.0
50.5
73.3
40.3
4.7
168.8
20.6
19.8
10.7
51.1
38.3
38.7
10. 1
87. 1
433.0
87.4
77.3
49.6
51.9
266.2
39.4
40.2
27.4
33.2
13.8
13.4
167.4
74.8
12.2
18.0
8.2
-3
113.5
981.3
103.0
1084.3
---Funding entries represent planned contractor expenditures stated in current dollars including an
adjustment for inflation.
102
-------
EMISSIONS ASSESSMENT OF
CONVENTIONAL COMBUSTION SYSTEMS
By
D. G. Ackerman Jr., J. W. Hamersma, B. J. Matthews
TRW Inc.
One Space Park
Redondo Beach, California 90278
103
-------
ABSTRACT
The Emissions Assessment of Conventional Combustion Systems (EACCS) is a
sampling and analysis program for comprehensive emissions characterization
and environmental assessment of stationary conventional combustion processes
in the following principal categories: electricity generation-external
combustion, electrical generation and Indus trial-internal combustion,
industrial-external combustion, commercial/institutional, and residential.
The EACCS program uses the EPA-IERL Level I/Level 2 phased approach
which is designed to provide comprehensive emissions information on all
process waste streams in a cost effective manner. Level 1 uses semiquant-
itative techniques of sampling and analysis to provide preliminary infor-
mation on emission to identify potential problems. Level 2 sampling and
analysis techniques are specific and quantitative for problem emissions
identified by Level 1.
All sources in the residential, electricity generation and industrial-
internal combustion, and gas-and-lignite-fired categories have been com-
pleted and draft reports written.
104
-------
SECTION 1
INTRODUCTION
The Emissions Assessment of Conventional Combustion Systems (EACCS)
Program is a sampling and analysis program for comprehensive emissions char-
acterization and environmental assessment of stationary conventional combustion
processes (SCCP). It is currently the largest EPA-funded program of its type.
SCCP under consideration are grouped into five principal categories:
Electricity generation - external combustion
Industrial - external combustion
Electricity generation and industrial - internal combustion
Commercial/institutional - space heating
Residential - space heating
Within these five principal categories, 50 source categories were defined
based on combustion method (external, internal), firebox design (e.g., pulver-
ized dry bottom, cyclone), and fuel type (e.g., gas, residual oil, anthracite).
The objective of the EACCS Program is to produce environmental assessments
of pollutant emissions by source category. The scope of the EACCS Program
includes the following major activities:
• Review and evaluate existing emissions data covering each of the
50 source categories in the five principal categories
• Acquire new emissions data by using Level 1 sampling and analysis
methodology from 170 test site covering the 50 source categories
• Conduct 21 Level 2 test activities, as required, by application
of the EPA/IERL philosophy of phased sampling and analysis
• Develop estimates of total multimedia pollutant emissions by
source category in order to perform the required environmental
assessments.
Because the EACCS program is based on the EPA/IERL phased approach to
environmental assessment (Reference 1), the sampling and analysis methodology
comprises a set of detailed procedures (Reference 2) designed to provide
internally consistent and comparable data.
105
-------
The phased approach to environmental assessments is designed to provide
comprehensive emissions information on all process waste streams in a cost
effective manner. To achieve this goal, two distinct sampling and analysis
levels are being employed in this program. Level 1 utilizes semiquantitative
(± a factor of 3) techniques of sample collection and laboratory and field
analyses to: provide preliminary emissions data for waste streams and pollu-
tants not adequately characterized; identify potential problem areas; and
prioritize waste streams and pollutants in those streams for further, more
quantitative testing. Using the information from Level 1, available resources
can be directed toward Level 2 testing which involves specific, quantitative
analysis of components of those streams which do contain significant pollutant
loadings. The data developed at Level 2 is used to identify control tech-
nology needs and to further define the environmental hazard associated with each
process stream. A third phase, Level 3, which is outside the scope of this
program, employs continuous or periodic monitoring of specific pollutants
identified at Level 2 so that the emission rates of these critical component??
can be determined exactly as a function of time and operating conditions.
Level 1 results are compared with a variety of evaluation criteria, e.g.,
Source Severity Factors (Reference 3) and MEG/MATE values (Reference 4).
Emissions with a Source Severity Factor of 0.05 or greater or which exceed
MEG/MATE values are flagged as potential problems or recommended for Level 2
analysis for further definition.
The first program activity was reviewing and evaluating existing emissions
data for each of the categories covered by the program. Preliminary results
from this evaluation were reviewed by EPA, and recommendations were made for
selecting the Level 1 test sites. (As Level 1 data are reviewed, the same
process is used to select Level 2 test activities).
All sources in the residential principal category have been tested, and a
draft final report is in review (Reference 5). A draft report on the internal
combustion category (Reference 6) is in review. Data on lignite- and gas-fired
utilities sites have been reviewed. This paper will discuss results from these
sources.
106
-------
SECTION 2
CONCLUSIONS
GAS- AND OIL-FIRED RESIDENTIAL SOURCES
The following conclusions were drawn from the emissions assessment of
gas- and oil-fired residental sources tested (Reference 5) .
• Gas-fired and oil-fired residential heating source categories
do not constitute a major environmental hazard. Source severity
factors for all pollutants calculated from emissions data are
well below 0.1. Source severity factors lower than 0.1 are
considered to be indicative that pollutant emissions are not
hazardous.
• Criteria pollutant emissions are variable and often not in
agreement with either EPA emission factors or existing data.
The variability in the data is probably because of natural
variations in residential combustion units, the semiquantitative
nature of Level 1 measurements, and, in the case of hydrocarbons,
differences in pollutant definition relating to measurement
technique. Severity factors for criteria pollutants are higher
for oil-fired systems than for gas-fired systems.
• SO emission levels per unit of fuel sulfur, based on a limited
number of analyses, are slightly in excess of those normally
found in utility systems. This finding, for which there is
some precedent, may be a real effect or the result of experimental
error at low total sulfur concentrations. i
• Trace element emissions are extremely low for gas-fired systems.
Trace elements from oil-fired systems are emitted to a greater
extent than from gas combustion but are largely comprised of
transition elements. Severity factors for all elements are well
below 0.1.
• POM emissions are essentially nonexistent from gas-fired resi-
dential sources. Some POMs are emitted from oil-fired com-
bustion. However, the most hazardous POM constituents; i.e.,
benzo(a)pyrene, were not detected and degree of hazard factors,
defined as the ratio of stack concentrations to MATE values,
for those POM compounds detected were well below 0.1.
107
-------
• On the basis of the above conclusions, no further sampling and
analysis is required for these sources. No Level 2 investi-
gation of any pollutant is required.
• Hydrocarbon and POM emissions were not significantly affected
by the change in burner cycle mode from 50 minutes on/10 minutes
off to 10 minutes on/20 minutes off. The effect of cycle on
emissions noted by other investigators is undoubtedly a real
effect but the change in emissions was not detectable in this
Level 1 sampling and analysis program.
INDUSTRIAL AND UTILITY INTERNAL COMBUSTION SOURCES
The following conclusions were drawn from the emissions assessment of
industrial and utility internal combustion sources (Reference 6).
• NO emissions from internal combustion sources are a potential
environmental problem. These emissions account for approximately
20 percent of the total NO emissions from stationary sources. Of
the NO emissions from internal combustion sources, more than 80
percent are contributed by the industrial reciprocating gas engine
category.. Source severity factors for NO emissions from gas
turbines and reciprocating engines range from 0.17 to 7.1.
• Emissions of hydrocarbons from internal combustion sources con-
tribute significantly to the national emissions burden. These
emissions account for approximately 9 percent of the total hydro-
carbon emissions from stationary sources. More than 80 percent
of the hydrocarbon emissions from internal combustion sources are
contributed by the- industrial reciprocating gas engine category.
Source severity factors for hydrocarbon emissions range from 0.01
for industrial gas-fueled gas turbines to 1.7 for industrial
reciprocating gas engines.
• CO emissions from internal combustion sources are not an environ-
mental concern -. Source severity factors for CO emissions from
internal combustion sources are all well below 0.05. Total CO
emissions from these sources account for approximately 1 percent
of CO emissions from all stationary sources. More than 80 percent
of the CO emissions from internal combustion sources are contributed
by the industrial reciprocating gas engine category.
• Emissions of S02 and particulates from Internal combustion sources
contribute only an insignificant fraction of the emissions of
these pollutants from stationary sources. Source severity factors
for SO, and participate emissions are well below 0.05, with the
exception of S02 emissions from diesel engines. Source severity
factors for S02 emissions from industrial and electricity
generation diesel engines are 0.08 and 0.10, respectively.
108
-------
Combination of emissions data from this measurement program and
the existing data base provides adequate characterization of
emissions of criteria pollutants from internal combustion sources.
SO, emissions from oil-fueled internal combustion sources are a
potential environmental problem. Source severity factors for S03
emissions range from 0.05 to 0.23. For distillate oil-fueled gas
turbines» an average of 3.8 percent of the sulfur present in the
fuel is converted to S0«. For diesel engines, an average of 1.4
percent of the fuel sulfur is converted to SO-. The percent of
fuel sulfur converted to SO is lower for diesel engines because
of the lower oxygen level in reciprocating engines.
For distillate oil-fueled gas turbines, the data base for SO.,
emissions is adequate. For distillate oil reciprocating engines,
the data base for SO., emissions could be improved by additional
field tests.
Emissions of trace elements from gas-fueled internal combustion
sources are negligible when compared with emissions of trace
elements from oil-fueled sources. For oil-fueled internal
combustion sources, emissions of copper, nickel, and phosphorus
have source severity factors greater than 0.05.
The data base for trace element emissions from diesel engines is
adequate. For distillate oil-fueled gas turbines, trace elements
for which the emissions data base is inadequate include nickel,
phosphorus, and silicon. The emissions data base for these trace
elements may be improved by analysis of additional fuel samples.
Emissions of individual organic species from internal combustion
sources are environmentally insignificant. Analyses of organic
samples have indicated that organic emissions from oil-fueled
internal combustion sources consist mainly of saturated and
unsaturated aliphatic and aromatic hydrocarbons. The most pre-
valent organic species present are saturated straight chain and
branched hydrocarbons. Substituted benzenes are the second most
abundant organic species emitted. Source severity factors for
these organic emissions are well below 0.05.
POM emissions from internal combustion sources are not at levels
of environmental concern. POM emissions from gas- and oil-fueled
gas turbines were at levels too low to be differentiated from
blank values. For diesel engines, the POMs emitted were mostly
naphthalenes and substituted naphthalenes, with source severity
factors well below 0.05. POM compounds known to be carcinogenic,
such as benzo(a)pyrene and dibenz(a,h) anthracene, were not found
above the detection limit of 0.05 yg/mj. Benzo(a)pyrene, the only
POM compound with MATE value below the detection limit, is unlikely
to be present, as no other POM compounds of molecular weight greater
than 202 were found.
109
-------
GAS-FIRED UTILITY SOURCES
From the gas-fired utility source tests, the following conclusions have
been drawn.
• Inorganic emissions are not a problem
• Particulate emissions are well below NSPS requirements
• Emissions of polycyclic organic materials (POMs) are not a
problem, as no POMs were found.
• CO data were scattered, and additional data may be necessary
• Hydrocarbon emissions for two non-tangential sites were scattered.
Acquisition of additional data is not recommended at this time.
LIGNITE-FIRED UTILITY SOURCES
The following conclusions were drawn from the emission assessment of
lignite-fired utility sources.
• Particulate emissions vary widely depending on control technology
used.
• ESPs effectively control particulate emissions.
• Present NO and SO data are suspect because of problems with
Level 1 methodology; sufficient data may be available from
AP-42.
• Ba, Ni, Cu, Ca, Be, and F exceed source severity standards in
the controlled sites.
• Organic emissions are generally high and vary widely but lower
than AP-42 data. Additional Level 2 testing is recommended.
• Significant amounts of organic material were found in all fly
ash, bottom ash, and water samples.
• Organic .material was primarily aliphatic and aromatic hydro-
carbons; sufficient esters and oxygenated compounds were not
present to distinguish them from the blanks.
• SO^ and particulate sulfate data is needed.
• Additional lignite data are necessary on all levels. Large
units in Texas should be considered.
no
-------
SECTION 3
TESTING
SOURCES TESTED
Gas- and Oil-Fired Residential Sources
Residential space heating systems consist of combustion units burning
natural gas, liquid petroleum gas (LPG), distillate oil, coal, and wood and
electric heating systems. The EACCS program focussed on gas (natural and
LPG) and oil, as they are the most important residential space heating fuels
representing, respectively, 60 percent and 38 percent of 1975 consumption.
Residential oil- (distillate) and gas-fired space heating equipment is
subject to a number of design variations relating to burners, combustion
chambers, excess air, heating medium, etc. Gas-fired systems are inherently
less complex and easier to maintain than oil-fired systems because the fuel
is cleaner and atomization is not required. Residential systems operate
only in an on/off mode. There are no other variations in fuel input rate
in contrast to load modulation encountered with larger commercial, industrial,
and utility sources.
Air emissions from the blue gas stack are the only significant emissions
from oil- and gas-fired residential heating units. Because these fuels are
relatively clean, the concentrations of air pollutants emitted from these
sources are low in contrast with those emitted from other combustion sources
to be evaluated during this program. However, because these sources are
numerous and have a high source-receptor relationship, they may be of envi-
ronmental importance.
Evaluation of existing emissions data on these sources indicated a strong
need for additional data, particularly an emissions of organic compounds.
Therefore, five representative gas- and oil-fired residential space heating
units each were tested.
Internal Combustion Sources
Stationary internal combustion sources for electricity generation and
industrial applications are grouped into two categories: gas turbines and
reciprocating engines. Gas turbines are classed into three general types of
cycles: simple open cycle, regenerative open cycle, and combined cycle.
Regenerative open cycle turbines constitute only a very small fraction of the
total gas turbine population. Emissions from identical gas turbines used in
111
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the combined and simple cycle modes are the same. Thus, only emissions from
simple open cycle gas turbines were evaluated.
Reciprocating internal combustion engines are classified according to the
method of ignition: spark and compression (diesel). Both spark and compression
ignition engines are further classified into two groups: four-cycle and two-
cycle. Most of the large bore, high power engines for utility and industrial
applications are four-cycle compression ignition engines designed to operate
as diesel fuel and two-cycle or four-cycle spark ignited gas engines.
The principal application areas for gas turbines and reciprocating
engines are: electricity generation, oil and gas transmission, natural gas
processing, and oil and gas production and exploration. In 1976 the installed
capacity of gas turbines was 46,570 MW in electrical utilities and 8,800 MW
for industrial applications. In 1976, the installed capacity of reciprocating
engines was 5,300 MW in electric utilities and 18,870 MW for industrial
applications.
Air pollution control equipment is generally not installed on gas turbines
or reciprocating engines. However, there is evidence that water and steam
injection are valid techniques for controlling NOx emissions from gas turbines.
Evaluation of existing emissions data on gas turbines indicated that the
data base on distillate oil fired turbines was inadequate for trace elements,
particulate sulfate, and organics. For distillate oil reciprocating engines,
the data base for SO-, particulate- sulfate, and organic emissions was found to
be inadequate. Emissions data for gas fired turbines and reciprocating engines
were adequate. To fill the deficiencies in the data base, one gas turbine,
five distillate oil turbine, and five distillate oil reciprocating engine
sources were tested.
Gas- and Lignite-Fired Utility Sources
Gas-fired utility sources were classified by combustion source type:
non-tangential and tangential firing. Evaluation of existing emissions data
indicated a need for additional data. Therefore, four non-tangential and
3 tangential fired heaters were tested using Level 1 methods.
Lignite-fired utility sources were also classified by combustion source
type:
• pulverized dry bottom (front fired)
• cyclone
• spreader stoker
Evaluation of existing emissions data indicated a need for further testing
of lignite-fired heaters. Consequently, three pulverized dry bottom, one
cyclone, and two spreader stoker sources were tested.
112
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SAMPLING AND ANALYSIS
Field Testing
Field testing procedures were on Level 1 environmental assessment methods
(Reference 1). The Source Assessment Sampling System (SASS) was used to
collect particulate, organic, and trace metal samples. The SASS train is a
high volume, 0.14 m^/min (5 scfm), system designed to extract particulates
and gases from the stack, separate particulates into four size fractions,
trap organics in an absorbent, and collect volatile trace metals in liquid
solutions. A high volume system is required to collect adequate quantities
of trace materials for subsequent laboratory analyses. The SASS train is
operated for a time sufficient to collect 30 m^ of stack gases.
Stack gas is drawn into the SASS train through a stainless steel probe.
Particulates are collected by a series of three cyclones (>10y, 3-lOp, >3y)
and a filter >0.1y. The cyclone and filter are in a heated oven maintained
at 150°C (300°F). From the cyclone oven, stack gas passes through the organic
vapor sorbent trap which cools the gas to 20°C and quantitatively traps
organic compounds boiling above 100°C. The trapping medium is XAD-2 resin, a
styrene-divinylbenzene copolymer. The sample stream is then drawn through
a series of four impingers. The first impinger contains hydrogen peroxide,
H202, which stabilizes stack gas components by oxidation. The second impinger
contains a solution of ammonium peroxydisulfate (Nlty)2&2®8» anc^ silver nitrate,
AoN03, to trap volatile trace metals and organometallic compounds. The third
impinger is a backup to the second and contains a solution of ammonium peroxy-
disulfate. The fourth impinger contains silica gel to remove moisture.
Compounds with boiling points (<100°C) too low to be retained by the
sorbent trap are analyzed in the field by gas chromatography. Gas samples
were collected in Tedlar bags using a reciprocating pump and stainless steel
probe. A cooling chamber was used between the stack and the Tedlar bag. Bag
samples were analyzed for GI to C6 alkanes by gas chromatography with flame
ionization detection. Inorganic gases CC>2, 02, N2 and CO were also separated
by gas chromatography but a thermal conductivity detector was used. Standard
gas mixtures were used to quantify the measurements.
Analyses of flue gases for NOX were conducted at gas-fired sites electro-
chemically. At oil-fired sites NOX emissions were sampled and analyzed using
U.S. EPA Method 7. Grab samples for NOX were collected in evacuated flasks
containing a dilute sulfuric acid-hydrogen peroxide absorbing solution.
Samples were analyzed in the laboratory colorimetrically using the phenoldi-
sulfonic acid procedure.
A Bacharach smoke spot tester was also used in the field.
Testing, reagents, and sample handling were in accord with Level 1
procedures. The recovery of samples and washing of the SASS train and sample
containers were all performed in the laboratory. All working surfaces were
washed with isopropyl alcohol prior to any contact. All containers and
113
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handling equipment were cleaned according to Level 1 specifications. Filters
were desiccated 24 hours in clean desiccators prior to any weighings.
Residential Sources—
Field tests were conducted at five gas- and five oil-fired residential
sites, using a stove pipe extension to provide a sampling port for the SASS
train. In all tests a 3-foot probe with a 5/8-inch nozzle was used.
Sampling was conducted at one point approximately in the center of the 8-inch
stack. The residential furnaces were operated on a cycle of 50 minutes on
and 10 minutes off. Sampling was conducted simultaneously with the furnace
operating period. At gas-fired sites, sampling time was about 3 hours
(30 m3 of gas were sampled) while at oil-fired sites the sampling duration
was about 10 hours (90 m3 of gas were sampled). The SASS train cyclones
were not used because the level of particulate emissions was very low. The
filter was, however, used.
Internal Combustion, Gas and Lignite Utility Sites—
Tests at the internal combustion and gas-fired utility sites were
conducted without the SASS train cyclones because of the low concentrations
of particulates and their characteristic small particle diameters. The SASS
train filter (spectrogradeR glass fiber) was used. Cyclones were used at
the lignite-fired utility sites.
Field tests were conducted at 11 internal combustion units. Seven of
the units had sampling ports located in the stack. The other four units
were tested by use of a 3-foot SASS probe fitted with a vertical nozzle
adaptor. The SASS probe was positioned approximately six inches above the
stack at a point where the vertical adaptor sampled down into the stack at
a traverse point of average stack velocity. Multiple-point traverses were
used to obtain blue gas samples at the seven gas and six lignite utility
sites.
Smoke spot numbers were determined using a Bachrach Smoke Spot Tester.
Visible emissions (percent opacity) were determined by a trained operator.
Water, solid waste and fuel samples were collected according to Level 1
SASS procedures. Limited water analyses were carried out in the field as
specified in the procedures manual.
Laboratory Analyses
Inorganic Analyses—
The Level 1 analysis (References 1 and 2) scheme was used for all
inorganic analyses. This scheme was designed to identify all elemental
species in the SASS train fractions and to provide semiquantitative data on
the elemental distributions and total emission factors. The primary tool for
the Level 1 analysis scheme is the Spark Source Mass Spectrograph (SSMS). The
114
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SSMS was chosen for Level 1 for its capability of detecting 70 elements
simultaneously with sub-ppm sensitivity. The SSMS data are supplemented
with atomic absorption spectrometry (AAS) data for Hg, As, and Sb and with
standard method determinations for chlorides.
The following SASS train sample types were analyzed for their elemental
composition: (1) the particulate filter (PF) , (2) the XAD-2 resin (XR) , and
(3) a composite sample containing portions of the condensate, the HN03 module
rinse, and the first impinger (CI) . In addition, for the oil-fired sources,
the fuel was also analyzed. Most of these sample types require some prepara-
tion prior to analysis. The XAD-2 resin and the fuel oil samples were prepared
for analysis by a Parr oxygen bomb combustion of the materials according to the
Level 1 procedures manual. The particulate filter samples were prepared by an
aqua regia extraction of the inorganic materials using a soxhlet apparatus
according to the EACCS procedures manual. The composite samples require no
special preparation prior to analysis.
Organic Analyses—
Level 1 organic analysis is a technique designed to identify organic
compounds beyond a total hydrocarbon equivalent analysis. It provides quali-
tative and quantitative data on volatile and nonvolatile organic compounds
(note that gaseous organics are measured in the field) collected in the SASS
train. Organics are recovered from all SASS train components. Stainless
steel components including the tubing are carefully cleaned with methylene
chloride or methylene chloride/methanol solvent to recover organics. Organics
in the condensate trap and XAD-2 resin are recovered by methylene chloride
extraction.
Because all samples are too dilute to detect organic compounds by the
majority of instrumental techniques employed, the first step is to concentrate
the samples from as much as 1000 ml to 10 ml in a Kuderna-Danish apparatus.
Methylene chloride is evaporated while the organics of interest are retained.
Kuderna-Danish concentrates are then evaluated by gas chromatography (GC),
infrared spectrometry (IR), liquid chromatography (LC), gravimetric analysis,
and sequential gas chromatography/mass spectrometry (GC/MS).
All samples are analyzed by GC/MS for specific polycyclic organic materials
(POM); i.e., compounds containing two or more ring structures. The mass peak
output data from the MS are evaluated by computer for all polycyclic organic
materials for which identification data are available. The detection limit is
about 0.9 yg/m£ of solution injected; in the specific residential tests about
0.3 ug/m3. Accuracy is within a factor of ±2.
GC analyses conducted in the field for gaseous compounds with boiling
points in the Ci~C6 range ( <100°C) are supplemented by laboratory analyses
for volatile organics (Cg-C17, 90 to 290°C) and nonvolatile^organics^ >C17,
>290°C). Separate analyses are also conducted for Cg (110°C to 140°C), Cg
(140°C to 160°C), CIQ (160 to 180°C), GH (180 to 200°C) and Ci2 (200 to 200°C)
organics. Except for the nonvolatiles which are measured gravimetrically
after evaporation all analyses are performed with GC using flame ionization
detection.
115
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The results of the above analyses are used to determine the next step in
the analysis. If the total organics (volatile and nonvolatile) indicate a stack
gas concentration below 500 pg/m3 then the procedure ends. If the organics are
above 500 yg/m3 then a class separation by liquid chromatography is conducted.
Liquid chromatography is carried out in water-jacketed columns in order to main-
tain homogeneity in column packing and assure reproducibility. A class separa-
tion of the sample placed on the column is accomplished with 6.5 gm of silica
gel packing. A gradient elution of various compounds is accomplished by sequen-
tial addition of solvents as indicated in Table 16.
After separation into eight fractions by liquid chromatography, volatiles
are measured by gas chromatography if the earlier determination indicated a
total concentration above 50 ug/m3. The nonvolatile portion of each fraction
is determined gravimetrically after evaporation.
Infrared spectrometry is used to analyze each LC fraction for functional
group in order to further specify the types of compounds in each fraction.
Samples are evaporated to dryness on KBr plates and analyzed with a grating
spectrophotometer. The use of KBr plates eliminates potential organic inter-
ferences. Each spectrograph is standardized against polystyrene film.
The overall accuracy and precision of these analyses are well within a
factor of ±2; i.e., if a number is reported as 50 yg, one can be 95 percent
confident that the true value is between 25 and 100 yg. Most of these analyses
are more accurate than ± factor of 2 with the exception of GC/MS.
116
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SECTION 4
RESULTS
RESIDENTIAL SITES
Gas-Fired Residential Sites
Basic flue gas composition data are shown in Table I for the gas-fired
residential sites. Measured particulate loadings were over 10 times lower
than the EPA emission factor (Reference 7) and comparable to those reported
by TRC (Reference 8). NO emissions were lower by a factor of 3 than exist-
ing EPA data (Reference 7). This has been timed to the sampling method.
Although not reported on Table I, opacity measurements and the smoke spot
index were zero for all five units.
Results of SSMS analysis for trace elements in filters and other SASS
train components were very low, reflecting the low contaminant levels in
natural gas. Trace element results from better catches were at the lower
detection limit of the SSMS and were equivalent to those observed in the
blanks for most elements.
Analyses for As, Hg, and Sb were performed by AAS. Mercury was found
only in the XAD-2 resin at concentrations ranging from 0.03 ug/m3 to 4 mg/m3.
Antimony was found at about 4 yg/m3 at only one site in the composite of the
condensate, module wash, and 1^02 impinger. Arsenic was found at the detec-
tion limit in all five sites and ranged from<0.16 to <0.56 yg/m3.
Emission concentrations of gaseous, volatile, and nonvolatile organic
compounds were determined, and the results are presented in Table II. The
C8~C12 factions varied from site-to-site and were generally present in
larger amounts than in the oil-fired residential sites. Virtually all vola-
tile organic compounds were found in the XAD-2 resin. Nonvolatile compounds
were found primarily in the walls of the sorbent trap module rather than in
the resin.
No POM compounds were found in the gas-fired residential site samples
other than naphthalene, dihydronaphthalene, and methyltetrahydronaphthalene,
which are so closely related to the resin itself (copolymer of styrene and
divinylbenzene) that these may have been artifacts of the sampling rather than
emitted compounds.
117
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Oil-Fired Residential Sites
Basic flue gas composition data are shown in Table III for the oil-fired
residential test sites. Measured particulate loadings were similar to those
found in the gas-fired residential sites and are roughly half those reported
by Battelle and recently adopted by EPA. NOX emission results were question-
able because of analysis difficulties. SOX data were not necessary.
Results of SSMS analyses for trace elements in filters and other SASS
train components were very low. Measured emissions of trace elements were
lower in almost all cases than those calculated from fuel analyses. Source
severity factors for trace elements were well below levels of concern.
Emission concentrations of gaseous, volatile, and nonvolatile organic
compounds were determined. Results are given in Table IV. Compounds in the
C1-C3 range (measured in the field) predominated, generally representing more
than 60% of the totals. Volatile compounds (Cg-C^) were considerably lower
than gaseous and nonvolatile compounds.
Results of GC/MS analyses for POM compounds are presented in Table V,
which shows only compounds found above the detection limit of 0.3 pg/m^. If
no value is given, the compound was not detected.
INDUSTRIAL AND UTILITY INTERNAL COMBUSTION SITES
Table VI presents source characteristics (source type, operating load,
and fuel used) and ©£, particulate, SO , and smoke number results. NOX and
CO emissions were not measured because the data base for these species was
adequate. SOX emissions data in Table VI were calculated from fuel sulfur
content and not measured in the field.
Particulate emissions determined from filter weights correlate well with
the Bachrach smoke readings, i.e., higher particulate emissions normally
correspond to higher smoke numbers. Particulate emissions from distillate
oil engines were much higher than from distillate oil turbines. SOx emissions
were low because of the low sulfur content of the fuels and the large amounts
of excess air generally present in the combustion gases from turbines and
reciprocating engines.
Table VII presents a summary of results of inorganic analyses. Mercury,
arsenic, and antimony emissions were all quite low. These three elements
were found primarily in the XAD-2 resin. SSMS analysis found the major
elements (0.3 mg/DSCM) present in all sites to be: Al, B, Ba, Ca, Cu, Fe,
R, Mg, Na, Ni, P, Pb, S, Si, and Zn.. Additionally, Mn was found at signifi-
cant levels in those sites (111, 306, and 307) using fuel containing an
organomanganese additive.
Table VIII presents a suramay of analysis results for gaseous (C1-C6),
volatile (C7-C16), and nonvolatile (>C17) organic compounds. There was
large variation in concentrations of C1-C6 compounds among the oil-fired
turbines. The total concentration of compounds in the C7-C16 range varied
from 200 to 3000 yg/m3 among the samples from the gas and oil fired turbines.
118
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The C7-C16 hydrocarbon content of samples from the diesel oil fired engines
ranged from about 10 to 20 yg/m3. On average, the diesel burning engines
emitted approximately 15 times more C7-C16 compounds than the gas or oil
fired turbines.
The nonvolatile organic content of samples from the diesel oil fired
sources were about 25 times greater than those from the gas or oil fired
turbines. The average total organic content of samples from gas or oil fired
turbines was 6 mg/m3, and the average total organic content of samples from
the diesel fired engines was 88 mg/m3.
No POM compounds were found in samples from the oil and gas fired tur-
bine sites; the detection limit for these samples was 0.08 yg/m3. Samples
from the diesel oil fired sites contained substantial amounts of hydrocarbon
oils which made POM quantitation difficult; however, the results presented in
Table IX are considered adequate because the levels of POMs found were
several orders of magnitude below levels of concern.
GAS AND LIGNITE - FIRED UTILITY SOURCES
Gas-Fired Utility Sites
Basic flue gas composition data are shown in Table X for the gas-fired
utility sites. Measured SOX and particulate emissions both were well below
NSPS requirements. Carbon monoxide results were scattered, and more data may
be required.
Because natural gas has minimal inorganic content, inorganic analyses of
samples from the gas-fired utility sites were not necessary.
Table XI presents emission concentration of gaseous, volatile and non-
volatile organic compounds from the gas-fired utility sources tested.
Measured hydrocarbon emissions were highly variable from all three groups of
compounds, and additional data should be acquired. No POM compounds were
found at a detection limit of 0.3 yg/m3.
Lignite-Fired Utility Sites
Basic flue gas composition data are shown in Table XII for the lignite-
fired utility boilers. Sites 314, 315, and 316 had multiclone control units
with design efficiencies of 84%, 84%, and 89.5%, respectively, for particu-
lates. Sites 318, 316, and 319 had electrostatic precipitator units with
design efficiencies of 98.5%, 99.05%, and 99.82%, respectively, for particu-
lates. Results in Table XII show that particulate emissions varied widely
with the control device used and that ESP units controlled particulate
emissions effectively. NOX and SOX data were acquired but were insufficiently
accurate to draw useful conclusions. Adequate data are, however, available.
Inorganic analyses of samples from these sites showed problem emissions
for many elements from those units with multiclone central devices.
Table XIII shows, by element, numbers of sites with source severity factors
119
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in several ranges. A source severity factor in excess of 0.1 indicates a
problem emission. Results in Table XIII show that ESP units are considerably
more effective at reducing emissions than are multiclone central devices.
Table XIV presents results of organic analyses of samples from the
lignite-fired sites. Emissions of gaseous, volatile, and nonvolatile com-
pounds are generally high in comparison to other sites tested but are lower
than AP-42 data on lignite-fired sites. Organic material was primarily
aliphatic and aromatic. Esters and other oxygenated compounds were not
found. Additionally, significant amounts of organic material were found in
all fly ash, bottom ash, and water samples from these sites. POM emissions
were below levels of interest.
120
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REFERENCES
1. Hamersma, J. W., et al., IERL-RTP Procedures Manual: Level 1 Environ-
mental Assessment. EPA-600/2-76-160a. June 1976.
2. Hamersma, J. W., et al., Emissions Assessment of Conventional Combustion
Systems Methods and Procedures Manual for Sampling and Analysis. Pre-
pared for Industrial and Environmental Research Laboratory. Office of
Research and Development. Chemical Processes Branch. U. S. Environ-
mental Protection Agency. December 1977. Contract No. 68-02-2197.
3. Eimutis, E. C., et al., Air, Water, and Solid Residue Prioritization
Models for Conventional Combustion Sources. EPA-600/2-76-176.
July 1976. 54 pp.
4. Cleland, J. G., and G. L. Kingsbury. Multimedia Environmental Goals for
Environmental Assessment. Volume I. EPA-600/7-77-136a. November 1977.
5. Draft Revised Final Report. Emissions Assessment of Conventional Combus-
tion Systems. Volume I : Gas-Fired and Oil-Fired Residential Heating
System Source Categories. Contract No. 68-02-2197. October 1978.
6. Draft Final Report. Emissions Assessment of Conventional Combustion
Systems. Volume II. Electricity Generation and Industrial Internal
Combustion Source Categories. Contract No. 68-02-2197. November 1978.
7. Compilation of Air Pollutant Emission Factors. U. S. Environmental
Protection Agency Report No. AP-42. February 1976.
8. Brooknan, G. T., and P. W. Kalina. TRC Measuring the Environmental
Impact of Domestic Gas-Fired Heating Systems. Paper presented at 67th
Annual Meeting Air Pollution Control Association. June 1974.
121
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Site
No.
TABLE I. FLUE,GAS COMPOSITION DATA FROM
GAS-FIRED RESIDENTIAL SITES
,2 .
CO
Off-
CO
PPM
Partlculate Emmissions
lb/10 Btu
Loading
Ug/nT
lb/10 Btu
100 16.7 6.4 <500 0.46 0.00097 25.3 0.054
101 12.9 1.4 <500 0.40 0.00048 9.4 0.011
102 19.5 3.0 <500 0.49 0.00069 18.8 0.027
103 19.1 1.7 <500 0.64 t).0013 12.5 0.026
104 16.8 1.1 <500 0.62 0.00075 9.3 0.011
122
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TABLE II. GASEOUS, VOLATILE AND NONVOLATILE ORGANIC EMISSIONS FROM GAS-FIRED
RESIDENTIAL SYSTEMS, pg/m3
to
Site
S
100 0*
101 0
102 0^
103 39.400
104 0
Average
Gaseous*
C2
0
0
0
37.800
0
C3
0
0
0
55.500
0
C4
0
0
0
0
0
C5
0
0
0
0
0
C6 C8
0 < 10
0 < 10
0 -
0 <10
0 <10
<10
Volatile
Total
C9 C10 Cll C12 C8"C12 C8"C17
<10 1.490 560 60 2,110
<10 <10 <10 <10 <10 -
_ -
<10 770 680 <10 1,450
<10 1,960 2.680 370 5,010
<10 l',060 980 110 2,150
Nonvolatile
>C17
400
1,240
780
480
920
760
Total organics^
crciv
-2,500
-1,240
>780
-1,900
-5,900
-2,500
*Less than 1000 )ig/»3,
fNot including (^-C,.
gases.
-------
TABLE III. FLUE GAS COMPOSITION DATA FROM
OIL-FIRED RESIDENTIAL SITES
Particulates
Site
No.
300
301
302
303
304
%2
17.2
17.4
19.6
17.3
17.5
CO
%
3.8
3.7
1.2
2.9
2.6
CO
<0.2
<0.2
<0.2
<0.2~
<0.2
/ 3
mg/m
2.3
1.2
2.2
2.5
1.9
lb/106 Btu
0.0082
0.0038
0.013
0.011
0.013
Smoke
Spot
Index
2
1
0.5
3
1.5
124
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ro
en
TABLE IV. GASEOUS, VOLATILE AND NONVOLATILE ORGANIC EMISSIONS FROM OIL-FIRED
RESIDENTIAL SYSTEMS, ug/m3
Site
300
301
302
303
304
Average
Gaseous
Cl
9,600
2,700
2,000
1,800
2,800
3,800
C2
1,700
1,900
400
<100
140
850
C3
<200
4,400
<200
<200
<200
< 1,000
C4
<300
<300
<300
<300
<300
<300
C5
<300
<300
<300
<300
<300
<300
C6
<400
<400
<400
<400
<400
<400
C8
6.3
1.2
7.5
1.2
5.2
4.3
C9
4.9
3.0
9.0
15
7.3
7.8
C10
46
14
26
43
43
34
Volatile
Cll
25
6.6
44
47
49
34
C12
1.3
33
45
65
81
45
Total
VC12
84
58
131
171
186
126
Nonvolatile
VC!7 >C17
170
180
560
560
320
360
650
1,800
290 to 560
1,200 to 1,400
6,000
2,000 to 2,400
Total orRanics
Cl"C6' C8~C17' >C17
12,000
11,000
3,000
3,600
9,300
7,800
to 13,000
to 12,000
to 4,700
to 5,100
to 10,500
to 9,100
-------
TABLE V. POLYCYCLIC ORGANIC MATTER RESULTS, OIL-FIRED RESIDENTIAL SYSTEMS, yg/m3*
ro
cr>
Site 301
Compound XAD-2
module rinse
Acenaphthene
Acetonaphthone
Anthracene
Azulene or naphthalene
Benzo(c)cinnoline
Biphenyl
Bu ty 1-phenan thr ene
Dimethyl naphthalene
Dimethyl phenanthrene
Ethyl naphthalene
Fluorenone 4 • 2
Methyl anthracene
Methyl-dibenzo thiophene
Methyl naphthalene
Methyl phenanthrene
Octyl phenanthrene
Phenanthrene 0.46
Phenanthrene quinone 4.2^
XAD-2
resin
9.3
2.3
20
1.2
23
23
4.7
2.4
4.7
1.2
Site 302 Site 303 Site 304
XAD-2 XAD-2 XAD-2 xAD-2
module rinse resin resin Condensate res±n
0.47
1.5
1.0
20
6.0 2.5
0.4
6.5
0.67
0.10
7.6 15.4
0.2
3.7
0.08 3.0 1.67
0.13
*0ther compounds were below the detection limit of about 0.3 yg/m .
Fluorenone or phenanthrene quinone.
-------
ro
TABLE VI. PARTICULATE AND SOX EMISSIONS FROM
INTERNAL COMBUSTION SOURCES TESTED
Combustion
Source Type
Gas Turbine
Distillate Oil
Turbine
Distillate Oil
Reciprocating
Engine
Site
No.
#110
#111
#112
#306
#307
#308
#309
#310
#311
#312
#313
Operating
Load
19.5 MW
18.0 MW
22.5 MW
14.5 MW
14.5 MW
20.2 MW
2.5 MW
2.5 MW
2.5 MW
2.5 MW
2.5 MW
S2
18.50
19.40
17.50
14.97
13.45
16.48
11.11
13.70
15.82
11.30
12.88
Particulate
*\
mg/nr
ND
6.71
2.91
2.46
3.85
4.37
21.02
29.41
33.15
12.44
15.71
Emissions
kg/GJ
ND
0.0214
0.0042
0.0021
0.0026
0.0049
0.0110
0.0208
0.0330
0.0066
0.0100
SOV Emissions
^y
ppm
ND
3.4
7.9
<1.9
<2.3
<1.4
60
81
58
43
44
kg/GJ
ND
0.0285
0.0306
<0.0042
<0.0042
< 0.0042
0.0831
0.1531
0.1531
0.0612
0.0743
Bachrach
Smoke No.
0
3.5
3.0
3.0
4.0
5.0
6.5
7.0
6.5
ND
6.0
-------
TABLE VII. SUMMARY OF RESULTS FROM SPECIFIC INORGANIC ANALYSES
Combustion
Source Type
Gas Turbine
Distillate Oil
Turbine
Distillate Oil
Reciprocating
Engine
Site
No.
110
111
112
306
307
308
309
310
311
312
313
Mass Emissions (mg/DSCM)
Hg
0.0091
0.00018
0.0014
< 0.00074
0.0016
< 0.00033
0.00016
0.00077
< 0.00091
< 0.00003
<0.0011
As
<0.0014
< 0.0056
< 0.0033
< 0.00009
<0. 00011
<0. 00019
<0. 00012
<0. 00017
< 0.00020
<0. 00011
<0. 00011
Sb
< 0.0016
< 0.0046
0.013
0.0017
0.0019
<0. 00016
< 0.00020
<0.0019
< 0.00024
< 0.00030
<0. 00019
j.
S°4
-
_
0.23
0.035
0.018
0.068
0.74
0.74
0.98
0.50
0.74
Cl F N03
0.89
4.9 0.010 0.029
2.5 0.049 0.018
- - -
_
_
_ _ _
- - -
_
-
_
*Values are from particulate samples only.
128
-------
TABLE VIH. VOLATILE AND NONVOLATILE ORGANIC EMISSIONS FROM INTERNAL COMBUSTION SYSTEMS
ro
10
Combination Source Type
Gas
Turblna
Site
Volatile Organic Gases
Ana?.yzed in Field, iig/m3
Cl
c2
C3
C4
C5
C6
Volatile Organic Materials
Analyzed in Laboratory by
GC-TCO Procedure: Uft/m^
C? (B.P. 90-110°C)
Cg (B.P. 110-140°C)
C9 (B.P. 140-160'C)
C,0 (B.P. 160-180-C)
Cu (B.P. 180-200°C)
C12 (B.P. 200-220°C)
C13 (C.P. 220-240"C)
C[4 (B.P. 240-260°C)
C[5 (B.P. 260-280°C)
C,, (. . 280-300°C)
16
Nonvolatile Organic
Matter >C16 From
Laboratory Gravimetric
Analysis, pg/m-*:
Total Organics, mg/m3
110
BL*
BL
BL
BL
BL
BL
483
1202
444
727
23
BL
29
BL
BL
BL
310
3.22
111
BL
BL
BL
BL
BL
BL
32
100
137
927
BL
84
BL
BL
BL
BL
6800
8.08
Distillate Oil
112
BL
BL
BL
BL
BL
BL
29
147
200
613
21
152
56
BL
46
457
3710
5.43
306
BL
67620
Bl
BL
BL
BL
100
52
7
17
89
6
28
210
484
783
440
69.8
Turbine
307
BL
15130
BL
BL
BL
BL
82
27
5
14
12
15
BL
BL
1
8
1400
16.7
308
BL
2275
BL
BL
BL
BL
BL
BL
BL
99
BL
25
12
11
38
71
1270
3.80
Distillate Oil
309
1000
7765
3535
BL
BL
BL
24
251
685
1488
1945
2916
4919
3632
3103
2606
56180
89.0
309-2
500
700
700
BL
BL
BL
10
370
850
2410
2890
3230
3000
3580
2760
2290
55330
76. C
310
1570
10380
3065
BL
BL
BL
214
328
633
1516
2292
2512
3827
3810
4192
3746
53880
92.0
311
2570
5970
1140
BL
BL
BL
98
497
683
1228
1265
1438
2899
1933
1810
1941
43040
66.5
Reciprocating Engines
312
3285
17540
705
BL
BL
BL
585
251
565
1704
2159
2663
3970
2413
2389
2149
63590
104
312-2
800
1900
BL
BL
BL
BL
90
400
1100
1800
2120
2450
2330
2200
2250
16GO
55040
71.5
313
4000
26015
745
BL
BL
BL
87
154
301
1034
682
1267
1742
1509
1771
937
46680
S6.9
313-2
1100
1700
BL
BL
BL
BL
BL
560
1290
2120
2580
3120
2810
3100
3010
2350
66340
87.3
BL Concentration of the species is below the
0.001 ppm (=0.5 vg/m3) per C,-C .
/ 16
limit of detection of th-j instrument; 1 ppm ( = 1000 ug/m3) per C.-C, and
-------
TABLE IX. POM EMISSIONS FROM DIESEL ENGINE SITES, vg/nf
Naphthalene
Methyl Naphthalenes
Dimethyl Naphthalenes
Biphenyl
C, Substituted Naphthalene
Dibenzothiophene
Methyl Dibenzothiophene
Phenanthrene
Methyl Phenanthrenes
Dimethyl Phenanthrenes
Trimethyl Phenanthrenes
Detection Limit of 0.2 ug
309
Possible
Rattget
32-15
-
60-28
5-2
16-7
10-5
-
16-7
40-19
8-4
-
0.2-0.07
Best
Est.
16
-
30
2
8
5
-
8
20
4
-
0.08
310
Possible
Ranget
22-16
26-20
14-11
7-6
5-4
2-1
1-0.7
3-2
10-7
1-0.7
3-2
0.1-0.07
311
Best Possible Best
Est. Ranget Est.
18 61-33 36
22 -
12 110-58 64
6 17-9 10
4 -
2 - -
0.8
3 - -
8 102-55 60
Q.a 41-22 24
2 -
0.08 0.1-0.07 0.08
312 3,
Possible Best Possible
Ranget Eat- Ranget
5-1
-
-
26-7
-
-
- -
_
120-70 77 270-70
72-42 46 110-28
ia-n 12 27-7
0.1-0.07 0.08 0.3-0.07
[3
Best
Est.
3
-
-
15
-
-
-
-
150
58
15
0.1
*POM's were only found in the XAD-2/XAD-2 module rinse sample,
range is given because of analysis problems (see text).
-------
TABLE X, FLUE GAS COMPOSITION DATA FROM GAS-FIRED UTILITY SITES
Combustion Site
Source Type No.
Non-Tangential 106
108
116
117
Tangential 113
114
115
02
5,85
9.08
7.88
6.47
4.81
4.62
8.64
SC>2 Emissions CO Emissions
ppm ppm
<1 <500
<1 <500
<1 42
<1 31
<10
<1 311
<1 481
Particulate Emissions
pg/m3
4,420
<32
531
<3.9
306
168
41
-------
TABLE XI. EMISSIONS OF GASEOUS, VOLATILE, AND NONVOLATILE ORGANIC COMPOUNDS
FROM GAS-FIRED UTILITY BOILERS
CO
ro
Combustion
Source Type
Non-Tangential
Tangential
Site
No.
106
108
116
117
113
114
115
Organic
Cl " C6
34,360-
45,200
No Data
21,500-
30,680
<9,460
<6,380
<12,760
<12,760
Emissions
C7 - C16
33,100
8,600
2,034
409
42
38
474
3
>C16
No
Data
7,400
679
383
1,846
902
2,246
Total Organic Emissions
yg/m3
>67,460
No Data
24,200-
33,390
790-
10,260
1,888-
8,266
940-
13,700
2,720-
15,480
-------
TABLE XII. FLUE GAS COMPOSITION DATA FROM LIGNITE-FIRED UTILITY SOURCES
CO
CO
Source Type
Pulverized
Dry Bottom
(Front Fired)
Cyclone
Spreader
Stoker
Site 2 CO
No. % Emissions, %
314 4.94 <500
315 4.70 <500
318 11.9 <500
316 7.0 <500
317 10.9 <500
319 * *
Particulate Emissions
Tota* Control Device,
m < 1 vi m 1 - 3pm >10pm mg/m Efficiency, %
2.1% 6.6% 56.5% 8480 Multiclone, 84%
1.1% 8.6% 50.9% 4625 Multiclone, 84%
- 2.83 ESP, 98.5
1.14 ESP, 99.53 (Tested)
22.3% 4.9% 59.2% 1630 Multiclone, 89.5%
- - 1.2 ESP, 99.82%
No data were acquired
-------
TABLE XIII. SOURCE SEVERITY FACTORS FOR INORGANIC ELEMENT EMISSIONS
FROM LIGNITE FIRED SOURCES*
Source Severity Factor Range
Element > 2 . 0
Al
As
B
Ba 2 (2)
Be
Ca 2 (2)
Cd
Cl
Co
Cr
Cu
F
Fe 2 (2)
Hg
K
Li
Mg 2 (2)
Mn
Na 2 (1)
Ni 1 (1)
P 2 (2)
Pb
Si
Sr
Ti
V
Zn
2.0
2
3
1
2
1
2
1
3
1
2
2
2
- 0.5
(2)
(2)
(1)
<2)
(1)
(2)
(1)
(1)
(1)
(2)
(2)
(2)
0.5
1
2
2
3
2
1
1
2
2
2
2
4
1
1
1
1
2
1
1
2
1
1
2
2
1
- 0.05
(1)
(2)
(2)
(1)
(1)
(1)
(1)
(2)
(2)
(2)
(1)
(1)
(1)
(1)
(2)
(1)
(1)
(1)
(1)
(2)
(2)
(1)
Total
3
2
2
5
5
4
1
2
2
2
4
4
3
1
2
2
3
2
4
5
5
2
3
3
2
2
1
Sites
(3)
(2)
(2)
(3)
(3)
(3)
(1)
(1)
(2)
(2)
(2)
(2)
(3)
(1)
(2)
(2)
(3)
(2)
(3)
(3)
(3)
(2)
(3)
(3)
(2)
(2)
(1)
*( ) indicates number of sites with mul tic lone emission control devices
134
-------
TABLE XIV. EMISSIONS OF GASEOUS, VOLATILE, AND NONVOLATILE ORGANIC COMPOUNDS
FROM LIGNITE-FIRED SITES
CO
in
Combustion Site
Source Type No.
Pulverized 314
Dry Bottom
(Front Fired)
315
318
Cyclone 316
Spreader 317
Stoker
319
Organic Emissions
Cl ~ C6 . C7 ~ °16
39,020- 434
44,520
5,340- 936
17,430
4,000- 558
13,000
10,680- 382
22,770
1,780- 643
13,870
No Data 26.9
C16
yg/m^
9,800
6,930
64
2,410
1,745
332
Total
o
yg/m
49,300-
54,800
13,200-
25,300
4,600-
13,600
13,500-
25,600
4,200-
16,300
No Date.
-------
ENVIRONMENTAL ASSESSMENT OF COAL
AND OIL FIRING IN A
CONTROLLED INDUSTRIAL BOILER
By:
K. W. Arledge
C. A. Leavitt
TRW Inc.
One Space Park
Redondo Beach, California 90278
137
-------
SECTION 1
INTRODUCTION
The industrial nations of the world are being forced to simultaneously
deal with two very difficult and contradictory problems. The relatively cheap
and convenient sources of energy are rapidly being depleted while the need for
increasingly stringent control of pollution is making the environmentally
acceptable use of the energy sources that are available more difficult. One
response to these dual needs has been to use the more abundant high polluting
fuels in combustion systems that have sophisticated pollution controls. The
technologies that are used to control pollution are new relative to combustion
technology. Therefore, the subtle short- and long-term effects of these new
technologies are not yet completely known.
The objective of this program is to conduct a comparative, multimedia
environmental assessment of oil versus coal firing in controlled industrial
and utility boilers and to draw conclusions about the comparative environ-
mental, energy, and societal impacts of firing oil versus firing coal.
This report presents the comparative assessment of controlled industrial
boilers. The major technical input for this assessment was feed stream and
emissions characterization data collected as part of the Conventional Combus-
tion Emission Assessment Program. These data were derived from rigorous
sampling and analysis and specify the types and quantities of solid, liquid,
and gaseous pollutants in each of the inlet and outlet streams of a controlled
oil- and coal-fired industrial boiler. A comprehensive assessment of each
fuel type in the controlled industrial boiler was accomplished to determine:
• The types and amounts of pollutants that are released during
poal and oil combustion in an uncontrolled boiler;
• The types and amounts of pollutants that are teleased during
the combustion of each fuel in a controlled boiler;
138
-------
• The effectiveness of the controls with respect to each
controlled pollutant;
• If the control devices modify pollutants that pass through
the controls;
• If the controls themselves create pollutants.
The comprehensive assessment results for the oil- and coal-fired indus-
trial boiler were then used in a comparative assessment to determine the
differences in the types and quantities of pollutants released.
The results of the industrial comparative emission assessments were then
evaluated to determine what conclusions could be drawn about the oil versus
coal firing. The comparative impacts identified were summarized by environ-
mental, energy, economic, and societal categories.
It should be kept in mind that the conclusions presented are based on
tests conducted on only one industrial boiler, one type of coal, and one type
of oil. It should not be assumed that these conclusions apply to all
industrial boilers under all circumstances. The results of this program
should, perhaps, best be thought of as a good indication of the impact
differences between coal and oil firing and as a set of guidelines on which
future work can be based.
139
-------
SECTION 2
CONCLUSIONS
Uncontrolled emissions of criteria pollutants produced by this boiler
during coal firing correspond well with emission factors from AP-42. This
observation does not generally hold true for oil-fired emissions. Full load
NOx emissions from oil firing were 19% lower than the AP-42 emission factor,
although they appear to be within the normal range for similar industrial
units. CO emissions from oil firing were nearly 63% lower than the AP-42
emission factor. Oil-fired S02 and total hydrocarbons correspond well with
their respective AP-42 emission factors. Particulate emissions from oil
firing, in the absence of coal ash contamination, are approximately twice the
value tabulated in AP-42.
emissions increased with increasing load for both coal and oil
firing, as expected. Available data indicate that for boiler loads between
90 and 100%, NOX emissions from coal firing are approximately three times
greater than from oil firing.
Uncontrolled S02 emission rates during coal and oil firing were 1112 ng/J
(2.59 Ib/MM Btu) and 993 ng/J (2.31 Ib/MM Btu) , respectively. Removal data
indicate an average scrubber removal efficiency of 97% during both coal and
oil firing. Controlled S02 emissions for coal and oil firing were 36.3 ng/J
(0.08 Ib/MM Btu) and 26.8 ng/J (0.06 Ib/MM Btu), respectively, which are lower
than either existing or proposed NSPS limitations.
Particulate loadings prior to scrubbing were 2951 ng/J (6.86 Ib/MM Btu)
during coal firing and 59.0 ng/J (0.14 Ib/MM Btu) during oil firing, in the
absence of coal ash contamination. Scrubbing removed 99% of the coal-fired
particulars and 75% of the oil-fired particulates. The lower removal
efficiency obtained during oil firing is attributed to the increased fraction
of particles smaller than 3 ym; at least 21% of the uncontrolled oil-fired
140
-------
particulates are less than 3 ym in diameter while substantially less than 1%
of uncontrolled coal-fired particulates are under 3 ym.
There appeared to be a net increase in emission rates across the scrubber
for coal fired particulates less than 3 ym in size. This net increase can be
attributed to the poor removal efficiency of the scrubber for fine particu-
lates, and to the sodium bisulfate (NaHSO^) and calcium sulfite hemihydrate
(CaS03 • 1/2 H20) particulates generated by the scrubber. Both NaHSC>4 and
CaSO-j • 1/2 H20 have been identified at the scrubber outlet but not at the
inlet. Although a very slight increase in oil-fired particulates in the
1-3 ym range was observed, a net decrease in particulates less than 3 ym was
observed during oil firing. Based on the results of coal firing tests, it
appears reasonable that scrubber generated particulates were present in the
scrubber outlet stream during oil firing but that the high fine particulate
loading associated with oil firing masked detection of these materials.
Of the 22 major trace elements analyzed in the flue gas stream during
coal firing, 18 exceed their MATE values at the scrubber inlet and four at the
scrubber outlet. Similarly, for oil firing, 11 exceeded their MATE values at
the scrubber inlet while five exceeded their MATE values at the scrubber out-
let. Elements exceeding their MATE values at the scrubber outlet and which
are common to both fuels are arsenic, chromium and nickel. Additionally, iron
exceeded its MATE value at the scrubber outlet during coal firing as did
cadmium and vanadium during oil firing. The overall removal of trace elements
across the scrubber is 99% for coal firing and 87% for oil firing.
The fraction of fuel sulfur converted to S0-j during oil firing was 50 to
75% higher than during coal firing. In contrast, the fraction of fuel sulfur
converted to sulfates during coal firing was twice that during oil firing.
Sulfates are more efficiently removed than SO^ (60% removal for oil
firing and 88% for coal firing) . This indicates that SO^" is probably asso-
ciated with the larger particulates, which are more efficiently removed than
smaller particulates. The higher sulfate removal from the coal flue gases is
explained by the higher particulate loading during coal firing.
Polycyclic organic material (POM) was not found in the scrubber inlet
or outlet at detection limits of 0.3 ug/m^ for either coal or oil firing.
141
-------
MATE values for most POM's are greater than this detection limit. However,
since the MATE values for at least two POM compounds - benzo(a)pyrene and
dibenz(a,h)anthracene - are less than 0.3 yg/rn-^, additional GC/MS analyses
at higher sensitivity would be required to conclusively preclude the presence
of all POM's at MATE levels.
Organic emissions for coal and oil firing were very similar. Total
organic emissions were less than 9 ng/J (0.02 Ib/MM Btu) for both tests, and
these emissions appear to be primarily Cj to C^ hydrocarbons and organics
heavier than Cjg. While uncontrolled emission rates for both coal and oil
firing are low, emissions of these organics were further reduced by about 75
to 85% in the scrubber unit.
The combined waste water stream from the boiler operation may not pose an
environmental hazard in terms of organic materials since the discharge concen-
trations of organics are well below their MATE values for both coal and oil
firing. The same conclusion may be drawn for inorganic compounds with the
exception of cobalt, nickel, copper and cadmium for coal firing and nickel
and copper for oil firing since these metals may exceed their MATE values.
The scrubber cake produced when either fuel is burned contains concentra-
tions of trace elements high enough to exceed most MATE values. Because of
these high concentrations the scrubber cake must be disposed of in specially
designed landfills.
The difference in environmental insult expected to result between coal
and oil combustion emissions from a single controlled 10 MW industrial boiler
is insignificant. This is because: 1) there are only slight differences in
the emissions levels of the pollutants, or 2) the absolute impact of either
fuel use is insignificant. The environmental impacts of emissions from a
cluster of controlled 10 MW industrial boilers are potentially significant.
The impacts include health effects, material damages, and ecological effects
from high levels of S02, NOX and suspended particulate matter; health effects
and ecological damage due to trace metal accumulation in soils and plants;
and aesthetic degradation from visibility reduction and waste disposal sites.
The environmental acceptability of a cluster of controlled industrial
boilers is more dependent on site specific factors (e.g., background pollution
142
-------
levels, location and number of other sources) than type of fuel utilized,
Careful control of the site specific factors can avert potential environmental
damages and generally compensate for any differential effects arising Between
the use of coal or oil.
Coal firing appears to produce a greater enrichment of trace elements in
the flue gas desulfurization cake than oil firing produces, However, the
scrubber cake resulting from either coal or oil firing contains sufficient
amounts of heavy metals and toxic substances that it must be disposed of in
specially designed landfills.
Based on the Lundy/Grahn Model for health effects associated with sus-
pended sulfate levels, regional emissions levels from controlled oil or coal-
fired industrial boilers would not be expected to cause a significant impact
on regional health. Emissions from uncontrolled boilers would result in
substantially greater levels of regional suspended sulfate levels, and the
associated health effects would be an order of magnitude greater.
The health impact of solid waste generation on health is essentially the
same for controlled coal firing and oil firing, provided suitable land
disposal techniques are employed to assure minimal leaching rates and migra-
tion of trace elements to groundwater and the terrestrial environment.
The potential for crop damage from either controlled coal firing or oil
firing depends greatly on ambient levels of NOX, S02, or trace element soil
concentrations. If such levels are presently high, localized plant damage
would be expected to occur within a 1 to 2 km range from a controlled boiler
cluster. Leaf destruction from S02 exposure would be expected to be slightly
more severe in the vicinity of a cluster of controlled boilers which are coal
fired as opposed to oil fired. For boilers uncontrolled for NOX emissions,
plant damage would be expected to be significantly greater in the vicinity of
the coal-fired cluster, owing to higher levels of ambient NOX produced. The
likelihood of damage occurring in plants due to emissions of trace elements
from either controlled oil or coal firing is remote, with the possible
exception of injury due to elevated levels of molybdenum and cadmium in plant
tissue resulting from coal firing and oil firing, respectively.
-------
The impact of boiler emissions on corrosion in the local area near a
cluster of controlled industrial boilers would be significant. The corrosion
rate would be slightly greater when the boilers are coal-fired. However, the
extent of this overall impact (oil or coal) is minor compared to that which
occurs when industrial boilers are uncontrolled.
The differential direct economic impact between emissions from coal fir--
ing and oil firing is generally insignfiicant with the possible exception of
some differences occurring in a limited localized area near clusters of
boilers. The extent of the incremental direct economic impacts is propor~
tional to the extent of the incremental environmental damages.
Differential second order economic impacts, such as changes in hospital
employment, alteration of taxes, or changes in income, are expected to be
insignificant between emissions from controlled oil and coal~fired industrial
boilers .
At the present time, the comparative assessment of the effects of
sions from controlled oil and coal-fired industrial boilers tends to support
the national energy plan for intensified utilization of coal. The fuel choice
of oil or coal is a relatively minor issue concerning the environmental accept-
ability of controlled industrial boilers; other site specific and plant design
factors exert a greater effect on environmental damages. While it was shown
that fuel choice caused significant differences in impacts to occur when the
boiler is uncontrolled for NOX emissions, these differences may be mitigated
by the addition of N0_ control technologies with minimal overall cost impact.
X
144
-------
SECTION 3
TEST AND ANALYSIS
The test unit used for this assessment is a dual fuel industrial process
steam boiler operated by the Firestone Tire and Rubber Company in Pottstown,
Pennsylvania. The 10 megawatt equivalent boiler is equipped with a pilot FMC,
Inc. flue gas desulfurization (FGD) unit that is designed to treat approxi-
mately one-third of the flue gas produced by the boiler when it is operating
at full load (3 megawatt equivalent). The boiler was originally designed to
burn coal but was later modified to burn either high volatile eastern bitu-
minous coal or Number 6 fuel oil. Table 1 presents a list of the major boiler
parameters. The boiler has no NOX controls.
The boiler and associated equipment produce four liquid waste streams:
boiler feed water pretreatment waste, steam drum blowdown, mud drum blowdown
and cooling water. All liquid waste streams except the cooling water are
mixed with process waste water from elsewhere in the plant. This combined
stream is then pumped directly into the municipal sewerage system. The boiler
cooling water is pumped directly into the municipal sewerage system without
mixing with other plant waste streams.
The pilot FGD unit is a double alkali scrubber that produces only a solid
cake as a waste product. The scrubber does not produce a liquid waste stream.
It is designed as a sulfur dioxide (SC^) and particulate control device, and
will operate on either fuel without modification.
Sampling and analysis of gaseous, liquid, and solid pollutants were con-
ducted according to the EPA Level I/Level 2 criteria, except that both Level 1
and Level 2 sampling were conducted simultaneously because of program time
constraints. Level I/Level 2 analysis procedures were followed except Level 2
analysis was conducted prior to receiving the results of Level 1 analysis in
those cases where sample degradation was anticipated. Figure 1 shows the
sampling locations.
145
-------
SECTION 4
COMPREHENSIVE ASSESSMENTS
Table 2 summarizes the annual emissions resulting from coal and oil
firing. The table presents estimates of air emissions both before and after
the scrubber. Liquid effluent and solid waste rates are presented for both
the controlled and uncontrolled cases.
Outlet emissions were determined on the basis of 100 percent of the flue
gas being treated by the scrubber. It was assumed that additional scrubber
modules, identical to the existing one, could be added such that all of the
flue gas was processed in exactly the same manner as the fraction that
actually passed through the scrubber. In this way, emissions from the pilot
scrubber were scaled up to represent the total flue gas flow. All emissions
data and conclusions are based on this assumption.
COMPREHENSIVE ASSESSMENT OF COAL FIRING
Criteria Pollutants
Uncontrolled emissions of criteria pollutants generally corresponded well
with values reported in AP-42. Although NOX emissions were slightly higher
than the average AP-42 value, they appear to be within the normal range for
similar industrial units.
NOX reductions varying from approximately 0 to 24 percent were measured
across the scrubber. However, the magnitude of NOX reductions could not be
correlated to changes in variables monitored during the test period (i.e.,
temperature, gas flow rate, liquid/gas ratio, boiler load, etc.). For this
reason, it is believed that observed N0% reductions are a sampling phenomenon,
perhaps related to leaks in the sample train.
Sulfur dioxide removal data indicated an average scrubber efficiency
of 97 percent. Controlled S02 emissions were 36.3 ng/J (0.08 pounds/MM Btu)
146
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which is less than either existing or proposed NSPS limitations for utility
boilers.
Mass balance data indicate that the multiclone unit upstream of the
scrubber was removing little or no fly ash during the test period. The
scrubber was found to remove 99.4 percent of the inlet particulate.
Inorganics
Although the removal efficiency for total particulates is high, there
appears to be a net increase in emission rates across the scrubber for
particulates less than 3 ym in size. This net increase can be attributed to
the poor removal efficiency of the scrubber for fine particulates, and to the
sodium bisulfate (NaHSC^) and calcium sulfite hemihydrate (CaS03 • 1/2 H20)
particulates generated by the scrubber. Both NaHSC^ and CaSC>3 • 1/2 H2Q have
been identified at the scrubber outlet but not at the inlet.
The relatively poor removal efficiency (approximately 30%) for 803 across
the scrubber is an indication that 863 is either present at very fine aerosols
in the scrubber inlet, or is converted to very fine aerosols as the flue gas
stream is rapidly cooled inside the scrubber.
Analysis has shown that while there may be higher surface concentrations
of sulfur-containing compounds in the particulates emitted from the scrubber,
most of the sulfur-containing compounds are probably present as solid sulfates
and sulfites. Thus, it is conceivable that sulfuric acid vapor is condensed
and deposited on the particulates emitted, whereas sodium bisulfate and cal-
cium sulfite hemihydrate are emitted as fine, solid particulates.
The overall sulfur balance indicates that over 92 percent of the fuel
sulfur is emitted as S02, less than 1 percent of the fuel sulfur is emitted
as 803, and approximately 3 percent of the fuel sulfur is emitted as SO, .
The overall removal efficiency for trace elements across the scrubber
is 99.5 percent. Of the 22 major trace elements, 18 exceed their MATE
values at the scrubber inlet and four at the scrubber outlet. The four trace
elements in the scrubber flue gas that pose a potential hazard are arsenic,
chromium, iron, and nickel. In addition, the emission concentration of beryl-
lium at the scrubber outlet is equal to its MATE value. The relative removal
147
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efficiency for trace elements across the scrubber can be explained by
enrichment theory. In general, trace elements that occur as element vapors
or form volatile compounds at furnace temperatures are more concentrated in
the smaller particulates, as a result of subsequent condensation and surface
adsorption. These are the same trace elements that are removed less
efficiently by the scrubber.
Mass balance closure for most of the trace elements have been found to be
in the 75 to 107 percent range. This closure instills confidence on the
validity of the sampling and analysis data for trace elements.
Organics
Total organic emissions were generally less than 9 ng/J (0.02 pound/MM
Btu) and these emissions appear to be primarily C^ to Cr hydrocarbons and
hydrocarbons heavier than C-^. While uncontrolled emission rates for C-j to
Gig and higher hydrocarbons are low, emissions of these organics were further
reduced by 21 to 35 percent in the scrubber unit.
Polycyclic organic material (POM) was not found in the scrubber inlet or
outlet at detection limits of 0.3 yg/m3. MATE values for most POM's are
greater than this detection limit. However, since the MATE values for at
least two POM compounds - benzo(a)pyrene and dibenz(a,h)anthracene - are less
than 0.3 yg/m3, additional GC/MS analyses at higher sensitivity would be
required to conclusively preclude the presence of all POM's at MATE levels.
Liquid Effluents
The combined wastewater stream generated from the boiler operation may
not pose an environmental hazard, since the discharge concentrations of most
inorganics and organics are all well below their MATE values. However, based
on the uncertainty in SSMS analyses, cobalt, cadmium, nickel and copper may
exceed their MATE values based on ecological considerations.
Solid Waste
The scrubber cake produced contains.a significant amount of coal fly ash.
With the exception of boron, trace element concentrations in the scrubber cake
far exceeded their MATE values. Because the trace elements may leach from the
disposed scrubber cake, these solid wastes must be disposed of in specially
148
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designed landfills.
COMPREHENSIVE ASSESSMENT OF OIL FIRING
Criteria Pollutants
Uncontrolled emissions of criteria pollutants do not generally correspond
with emission factors from AP-42. NOX emissions were nearly 23 percent lower
than the AP-42 emission factor, although they appear to be within the normal
range for similar industrial units. CO emissions were nearly 63 percent lower
than the AP-42 emission factor. SC>2 and total hydrocarbons corresponded well
with their respective AP-42 emission factors. Particulate emissions, in the
absence of coal ash contamination, are approximately twice the value
tabulated in AP-42.
Sulfur dioxide removal data indicated an average scrubber efficiency of
97 percent. Controlled S02 emissions were 26.8 ng/J (0,06 Ib/MM Btu) which is
less than either existing or proposed NSPS limitations for utility boilers.
Inorganics
Particulate removal data indicate that, on the average, scrubber effi"-
ciency was 84 percent during the test period. However, based on particulate
catches essentially free of coal ash contamination, the scrubber efficiency
was approximately 75 percent for oil firing particulates.
When emissions are uncontrolled, over 90 percent of the sulfur in the
fuel feed is emitted as SC^, less than 1 percent as 803, and 1,5 percent as
so4=.
S02 is efficiently removed by the scrubber (97 to 98 percent efficiency) .
The SO, removal efficiency (28 to 29 percent) suggests that S03 is associated
with fine particulates or aerosols. S0,= is about 60 percent removed by the
scrubber, and so is probably associated with the larger particulates.
Of the 22 major trace elements analyzed in the flue gas stream, 11
exceeded their MATE values at the scrubber inlet while only 5 exceeded MATE
values at the scrubber outlet. These 5 elements are arsenic, cadmium, chro-
mium, nickel and vanadium. With the exception of chromium, elements exceeding
their MATE values at the scrubber outlet were removed from the flue gas stream
with efficiencies lower than the overall average removal efficiency of
149
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87 percent.
Beryllium emissions were 0.001 mg/m3 after scrubbing; this corresponds to
ahlf the MATE value for this element. At this emission concentration, the
National Standard for Hazardous Air Pollutants limitation of 10 grams beryl**
lium per day would only be exceeded by boilers of 100 MW capacity or greater.
Mass balance closure for 10 of the 20 trace elements analyzed is between
50 and 136 percent. Poorer mass balance closure was obtained for the remain-
der of the trace elements due to the extremely low concentrations and/or
contamination of the scrubber recycle solution by coal firing components,
Organics
Organic emissions determined by FID analysis were generally less than
5 ng/J (0.01 Ib/MM Btu) and appear to be composed primarily of C, to Cg
hydrocarbons and organics heavier than C^, However, gas chromatograph and
gravimetric data indicate that FID values may be low by a factor of 2 to 3.
Approximately 88 and 83 percent of the Cy to C-^ and higher than C16 organics,
respectively, were removed by the scrubber
The organic compounds identified in the gas samples were generally not
representative of combustion-generated organic materials, but were compounds
associated with materials used in the sampling equipment and in various analy-
tical procedures. This again confirms the low level of organic emissions.
Polycyclic organic material (POM) was not found in the scrubber inlet or
outlet streams at detection limits of 0.3 jig/m3. MATE values for most POM's
are greater than this detection limit. However, since the MATE values for at
least two POM compounds - benzo(a)pyrene and dibenz(a,h)anthracene - are less
than 0.3 yg/m3, additional GC/MS analysis at higher sensitivity would be
required to conclusively preclude the presence of all POM's at MATE levels,
Liquid Effluents
The combined wastewater stream from the boiler operation may not pose an
environmental hazard in terms of organic materials since the discharge concen-
trations of organics are all well below their MATE values. A similar conclu-
sion may be drawn with respect to inorganic materials since inorganics, with
the exception of nickel and copper, did not exceed their MATE values for liquid
150
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streams. Owing to uncertainty associated with SSMS analysis, nickel and
copper may exceed their MATE values although this is not necessarily the
case.
Solid Waste
With the exceptions of antimony, boron, molybdenum and zinc, trace
element concentrations in the scrubber cake exceed their MATE values.
Because the trace elements may leach from the disposed scrubber cake, these
solid wastes must be disposed of in specially designed landfills.
151
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SECTION 5
COMPARATIVE ASSESSMENTS
The comprehensive assessments were used to develop a comparative
emissions and environmental assessment,
COMPARATIVE EMISSIONS ASSESSMENT
Criteria Pollutants
Uncontrolled emissions of criteria pollutants produced during coal
firing correspond well with emission factors from APr42, This observation
does not generally hold true for oil fired emissions. Full load NO^ emissions
from oil firing were 19 percent lower than the AP-42 emission factor, although
they appear to be within the normal fange for similar industrial units. CO
emissions from oil firing were nearly 63 percent lower than the AP-42 emission
factor. Oil-fired S02 and total hydrocarbons correspond well with their res-
pective AP-42 emission factors. Particulate emissions from oil firing, in the
absence of coal ash contamination, are approximately twice the value tabulated
in AP-42.
NOX emissions increased with increasing load for both coal and oil
firing, as expected. Available data indicate that for boiler loadings
between 90 and 100 percent, NOX emissions from coal firing are approximately
three times greater than from oil firing.
Observed reductions of NOX emissions for coal firing and early oil firing
tests appear to be due, at least in part, to air leakage into the scrubber
outlet sampling line. Data from later oil firing tests, not known to be sub-'
ject to leakage problems, indicate that NOX removal across the scrubber is on
f
the order of 2 percent.
Uncontrolled CO emissions from coal firing were 15.9 ng/J (0.04 Ib/MM Btu)
while those from oil firing were 5.47 ng/J (0.01 Ib/MM Btu), This factor of
152
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three difference is at variance with AP-42 data indicating that CO emissions
from oil firing are 23 percent lower than those from coal firing. Apparent
reductions in CO emissions across the scrubber are not considered significant
due to air leakage in the sampling train and the low sensitivity of analysis
at the measured CO concentrations.
Uncontrolled S02 emission rates during coal and oil firing were 1112 ng/J
(2.59 Ib/MM Btu) and 993 ng/J (2.31 Ib/MM Btu), respectively. Removal data
indicate an average scrubber removal efficiency of 97 percent during both coal
and oil firing. Controlled S02 emissions for coal and oil firing were 36.3
ng/J (0.08 Ib/MM Btu) and 26.8 ng/J (0.06 Ib/MM Btu), respectively, which are
lower than either existing or proposed NSPS limitations.
Particulate loadings prior to scrubbing were 2951 ng/J (6.86 Ib/MM Btu)
during coal firing and 59.0 ng/J (0.14 Ib/MM Btu) during oil firing, in the
absence of coal ash contamination. Scrubbing removed 99 percent of the coal-
fired particulates and 75 percent of the oil-fired particulates. The lower
removal efficiency obtained during oil firing is attributed to the increased
fraction of particles smaller than 3 ym; at least 21 percent of the uncon-
trolled oil-fired particulates are less than 3 ym in diameter while
substantially less than 1 percent of uncontrolled coal-fired particulates are
under 3 ym.
There appeared to be a net increase in emission rates across the scrubber
for coal-fired particulates less than 3 ym in size. This net increase can be
attributed to the poor removal efficiency of the scrubber for fine particula-
tes, and to the sodium bisulfate (NaHSO^ and calcium sulfite hemihydrate
(CaSO • 1/2 H20) particulates generated by the scrubber. Both NaHSO^ and
CaS03 • 1/2 H20 have been identified at the scrubber outlet but not at the
inlet. Although a very slight increase in oil-fired particulates in the
1-3 ]im range was observed, a net decrease in particulates less than 3 ym was
observed during oil firing. Based on the results of coal firing tests, it
appears reasonable that scrubber generated particulates were present in the
scrubber outlet stream during oil firing but that the high fine particulate
loading associated with oil firing masked detection of these materials.
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Inorganics
Of the 22 major trace elements analyzed in the flue gas stream during
coal firing, 18 exceed their MATE values at the scrubber inlet and four at
the scrubber outlet. Similarly, for oil firing, 11 exceeded their MATE values
at the scrubber inlet while five exceeded their MATE values at the scrubber
outlet. Elements exceeding their MATE values at the scrubber outlet and which
are common to both fuels are arsenic, chromium and nickel. Additionally, iron
exceeded its MATE value at the scrubber outlet during coal firing as did
cadmium and vanadium during oil firing. The overall removal of trace elements
across the scrubber is 99 percent for coal firing and 87 percent for oil
firing.
Beryllium emissions after scrubbing were less than or equal to the
beryllium MATE value during coal and oil firing. At the measured emission
concentrations, the National Standard for Hazardous Air Pollutants limitation
of 10 grams beryllium per day would only be exceeded by boilers of 50 MW
capacity for coal firing and 100 MW capacity for oil firing.
The fraction of fuel sulfur converted to 863 during oil firing was 50 to
75 percent higher than during coal firing. In contrast, the fraction of fuel
sulfur converted to sulfates during coal firing was twice that during oil
firing.
Sulfates are more efficiently removed than SO- (60 percent removal for
oil firing and 88 percent for coal firing). This indicates that S0,= is
probably associated with the larger particulates, which are more efficiently
removed than smaller particulates. The higher sulfate removal from the coal
flue gases is explained by the higher particulate loading during coal firing.
Uncontrolled chloride and fluoride loadings were higher during coal
firing (5 and 0.2 ng/J, respectively) than during oil firing (0.2 and 0.02
ng/J, respectively. This was attributed, in the case of chlorides, to a
higher fuel chlorine content for coal than for oil. Chlorides were removed
with better than 99 percent efficiency from coal flue gases and with about
51 percent efficiency from oil flue gases. This difference was attributed
to the higher particulate removal efficiency for coal particulates. Fluorides
were removed with greater than 86 percent and about 87 percent efficiency for
154
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coal and oil firing, respectively. Uncontrolled nitrate emissions were 0.08
ng/J during oil firing, and nitrates were removed from oil flue gases with
57 percent efficiency.
Organics
Polycyclic organic material (POM) was not found in the scrubber inlet
or outlet at detection limits of 0.3 yg/m3 for either coal or oil firing.
MATE values for most POM's are greater than this detection limit. However,
since the MATE values for at least two POM compounds - benzo(a)pyrene and
dibenz(a,h)anthracene - are less than 0.3 ug/m^, additional GC/MS analyses at
higher sensitivity would be required to conclusively preclude the presence of
all POM's at MATE levels.
Organic emissions for coal and oil firing were very similar. Total
organic emissions were less than 9 ng/J (0.02 Ib/MM Btu) for both tests, and
these emissions appear to be primarily Ci to C, hydrocarbons and organics
heavier than Cig. While uncontrolled emission rates for both coal and oil
firing are low, emissions of these organics were further reduced by about
75 ta 85 percent in the scrubber unit.
The organic compounds identified in the gas samples from both coal and
oil firing were generally not representative of combustion-generated organic
materials, but were compounds associated with materials used in the sampling
equipment and in various analytical procedures. This again confirms the low
level of organic emissions.
Liquid Waste
The combined waste water stream from the boiler operation may not pose an
environmental hazard in terms of organic materials since the discharge concen-
trations of organics are well below their MATE values for both coal and oil
firing. The same conclusion may be drawn for inorganic compounds with the
exception of cobalt, nickel, copper and cadmium for coar firing and nickel and
copper for oil firing since these metals may exceed their MATE values.
Solid Waste
The scrubber cake produced when either fuel is burned contains concen-
trations of trace elements high enough to exceed most MATE values. Because of
155
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these high concentrations the scrubber cake must be disposed of in specially
designed landfills.
COMPARATIVE ENVIRONMENTAL ASSESSMENT
The difference in environmental insult expected to result between coal
and oil combustion emissions from a single controlled 10 MW industrial boiler
is insignificant. This is because: 1) there are only slight differences in
the emissions levels of the pollutants, or 2) the absolute impact of either
fuel use is insignificant. The environmental impacts of emissions from a
cluster of controlled 10 MW industrial boilers are potentially significant.
The impacts include health effects, material damages, and ecological effects
from high levels of S02, NOX and suspended particulate matter; health effects
and ecological damage due to trace metal accumulation in soils and plants;
and aesthetic degradation from visibility reduction and waste disposal sites.
The risk of environmental damage from emissions of controlled industrial
boilers, whether oil or coal-fired, is considerably less than the risk posed
by emissions from uncontrolled industrial boilers. It should be noted that
this finding is based on an exceptional facility. The reference facility is
very well run and maintained, and emissions are low.
The environmental acceptability of a cluster of controlled industrial
boilers is more dependent on site specific factors (e.g., background pollution
levels, location and number of other sources) than type of fuel utilized.
Careful control of the site specific factors can avert potential environmental
damages and generally compensate for any differential effects arising between
the use of coal or oil.
With the possible exception of ambient levels of NOx, the risk of
violating the National Ambient Air Quality Standards (NAAQS) due to the
operation of clusters of controlled industrial boilers is essentially the same
whether the fuel combusted is coal or oil. Based on tests of the reference
10 MW boiler (which was not controlled for NOX emissions) , localized NOX con-
centrations produced by coal firing are estimated to be twice the level of
that resulting from oil firing, and greater than the levels permitted by the
NAAQS for 24-hour and one-year averaging periods.
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Short term (3-hour and 24-hour averaging times) maximum ambient concen^
trations present the most significant air pollution problem resulting from
operation of controlled industrial boilers. Restrictions imposed by the NAAQS
for short term ambient levels would be most constraining to boiler operation
in areas where air quality is already only marginally acceptable. Expected
long term concentrations arising from boiler emissions would not appear to
pose a risk for violation of the NAAQS.
Coal firing appears to produce a greater enrichment of trace elements
in the flue gas desulfurization cake than oil firing produces. However, the
scrubber cake resulting from either coal or oil firing contains sufficient
amounts of heavy metals and toxic substances to pose difficult waste disposal
problems.
The impact categories considered include public health, ecology, societal,
economic, and energy. The specific findings with respect to the various
impact categories are summarized briefly below.
Health Effects
Based on the Lundy/Grahn Model for health effects associated with
suspended sulfate levels, regional emissions levels from controlled oil or
coal-fired industrial boilers would not be expected to cause a significant
impact on regional health. Emissions from uncontrolled boilers would result
in substantially greater levels of regional suspended sulfate levels, and the
associated health effects would be an order of magnitude greater.
Emissions from clusters of controlled industrial boilers are expected
to cause significant adverse health effects in a localized area near the plant
cluster. Oil firing would be expected to result in localized health effects
about one third less severe than those resulting from coal firing. The
increase in mortality attributable to either controlled coal or oil firing is
appreciably less than that associated with uncontrolled industrial boilers
emitting higher levels of particulates and SOX.
The impact of solid waste generation on health is essentially the same
for controlled coal firing and oil firing, provided suitable land disposal
techniques are employed to assure minimal leaching rates and migration of
trace elements to groundwater and the terrestrial environment.
157
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Addition of cadmium to a localized environment in the quantities
produced by clustered controlled industrial boilers may result in cadmium
concentrations in living plants approaching levels injurious to man. Because
cigarettes contain significant cadmium levels, smokers are more apt to achieve
thresholds of observable symptoms for cadmium exposure when consuming
additional cadmium via the food chain.
The concentration of metals in runoff waters due to controlled oil
firing is predicted to be slightly less than that occurring from controlled
coal firing; in either case, hazard to human health by drinking water is
remote.
Trace element emissions from clusters of controlled industrial boilers
may significantly increase local background levels in drinking water, plant
tissue, soil, and the atmosphere; however, the expected increases in the
levels of such elements are generally several orders of magnitude less than
allowable exposure levels. Oil firing is estimated to cause cadmium burdens
in plants approaching levels injurious to man, and coal firing may produce
plant concentrations of molybdenum which are injurious to cattle.
Ecology
The potential for crop damage from either controlled coal firing or oil
firing depends greatly on ambient levels of NOX, SC>2, or trace element soil
concentrations. If such levels are presently high, localized plant damage
would be expected to occur within a 1 to 2 km range from a controlled boiler
cluster. Leaf destruction from S02 exposure would be expected to be slightly
more severe in the vicinity of a cluster of controlled boilers which are coal-
fired as opposed to oil-fired. For boilers uncontrolled for NOX emissions,
plant damage would be expected to be significantly greater in the vicinity of
the coal-fired cluster, owing to higher levels of ambient NOX produced. The
likelihood of damage occurring in plants due to emissions of trace elements
from either controlled oil or coal firing is remote, with the possible excep-
tion of injury due to elevated levels of molybdenum and cadmium in plant
(
tissue resulting from coal firing and oil firing, respectively.
The effect of emissions from industrial boilers on trace element burdens
in plants would be greater via soil uptake than by foliar interception. This
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is because soil concentrations are the result of accumulative long term
exposure to boiler emissions whereas foliar exposure is determined by the
immediate deposition rate of emissions on the plant surface and the lifetime
of the leaf.
The impact of fossil fuel combustion in controlled oil or coal-fired
boilers on plant damage via acid precipitation would be insignificant. The
levels of supended sulfate (the origin of acid rain) would be essentially the
same whether the controlled boilers are coal or oil fired.
Measurement and analyses of leaching rates at experimental waste disposal
sites indicate that landfills of untreated flue gas desulfurization system
scrubber cake can be constructed such that significant adverse impacts will
not occur.
Societal
The impact of boiler emissions on corrosion in the local area near a
cluster of controlled industrial boilers would be significant. The corrosion
rate would be slightly greater when the boilers are coal-fired. However, the
extent of this overall impact (oil or coal) is minor compared to that which
occurs when industrial boilers are uncontrolled.
The increase in annual TSP and soiling damages in the vicinity of a
cluster of controlled industrial boilers would result in additional cleaning
and maintenance costs about 10 to 15 percent greater than that already
experienced in a typical urban area. The cleaning costs may be slightly
greater when the boilers are coal-fired.
Emissions of particulate matter from controlled industrial boilers would
result in visibility reduction. This aesthetic degradation would occur in a
localized area near the boiler cluster, and would occur to essentially the
same extent whether the boilers are oil or coal-fired.
Total land disposal requirements for scrubber cake waste generated by
controlled coal firing are three times greater than those for controlled oil
firing. Waste disposal of the scrubber wastes may result in significant
depreciation of property value and aesthetic degradation in the area of the
disposal site. These impacts would be more severe if boilers use coal rather
than oil.
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Economic
The differential direct economic impact between emissions from coal
firing and oil firing is generally insignificant with the possible exception
of some differences occurring in a limited localized area near clusters of
boilers. The extent of the incremental direct economic impacts is
proportional to the extent of the incremental environmental damages.
Differential second order economic impacts, such as changes in hospital
employment, alteration of taxes, or changes in income, are expected to be
insignificant between emissions from controlled oil and coal-fired industrial
boilers,
Energy
At the present time, the comparative assessment of the effects of emis-
sions from controlled oil and coal-fired industrial boilers tends to support
the national energy plan for intensified utilization of coal. The fuel choice
of oil or coal is a relatively minor issue concerning the environmental
acceptability of controlled industrial boilers; other site specific and plant
design factors exert a greater effect on environmental damages. While it was
shown that fuel choice caused significant differences in impacts to occur when
the boiler is uncontrolled for NOX emissions, these differences may be
mitigated by the addition of NOX control technologies with minimal overall
cost impact.
As concern for environmental protection increases, the issue may not be
whether coal or oil use is more environmentally acceptable, but whether the
increasing use of fossil fuels can be continued at the present levels of con-
trol technology without potential long term damages. If it is found that long
term effects of pollution (e.g., trace metals accumulation, lake acidity from
acid rains) from fossil fuel combustion and other sources are environmentally
unacceptable, it is clear that energy use may be affected. Energy cost will
increase with increasing control requirements, possibly to the level where
other cleaner forms of energy become more competitive.
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TABLE 1. SUMMARY OF BOILER PARAMETERS
Boiler type:
Manufacturer:
Type of burner:
Number of burners:
Burner arrangement;
Air preheater:
Fuel:
Design steam rate:
Use:
Oil/pulverized coal;
face fired;
integral furnace;
dry bottom
Babcock and Wilcox, Type P-22 EL
Circular conical
3
Triangular, one face
Yes
Number of 6 fuel oil;
High volatile bituminous coal,
Class II, Group 2, of ASTM D388
45,000 kg/hr (100,000 Ib/hr);
Process steam
FEEDWATER
PRETREATMENT
UNIT
EXHAUST
GAS TO STACK
EXHAUST GAS
TO STACK
TO MUNICIPAL
SEWAGE
TREATMENT
LEGEND
1 - FUEL
2 - SLOWDOWN
3- FLYASI
4 - EXHAUST GAS
FGD INLET
5 - EXHAUST GAS
FGD OUTLET
6- SCRUBBER CAKE
7 - MAKE UP WATER
8 - SCRUBBER FEED SOI IDS
Figure 1. Diagram of boiler and flue gas desulfurization
system showing sampling locations.
161
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TABLE 2. ANNUAL EMISSIONS
ro
Pollutant
Gaseous NOx (as N02)
S02
S03
S04*
CO
Organic: (as CH4)
C] - Cfi1'
C7 - Cl6
Cie-f
Total Participates
10,
Coal Firing
500,810
1,127,300
6,184
67,214
16,119
5,870
-=5,606
345
2,311
2,991,700
--
— •
—
--
Oil Firing
164,230
906,202
7,249
20,894
4,991
2,272
<;4,164
155
2,381
53.832
—
—
--
—
kg/year
Coal/011
3.05
1.24
0.85
3.22
3.23
2.58
.-
2.22
0.97
55.6
--
--
—
—
Coal Firing
442,520
36,800
4,157
8,110
14,497
6,377
<5,606
274
335
18.856
11,691
5,667
1,320
188
scrubber Outlet
Oil Firing
157,390
24,453
5,183
8,303
4,845
2,500
<4,164
18
392
13,686
11,359
1,642
634
0*
Coal /Oil
2.81
1.51
0.80
0.98
2.99
2.55
-*-
15.2
0.85
1.38
1.03
3.45
1.93
—
m3/year
Liquid Blowdown/Waste Water
Cooling Water
Solid Bottom Ash
Fly Ash
Scrubber Cake
•v-76,000
•^6,000
-v 778,600
•v-J ,800,000
0
-v 76,000
% 86,000
•v 7,600
*> 15,000
0
•v 1
•v 1
•\. 103
-v 120
—
-v 76,000
86,000
«. 778,600
tl, 800, 000
8,054,100
t.76,000
0*6,000
•». 7,600
t.15,000
3,011,000
'. 1
*
•v.103
•>.120
Z.67
Assuming 100X load, 45 weeks per year (7,560 hrs/year}.
t
These values represent the detection limit of the instrument used.
These values represent oil firing participate with a minim* of coal ash contanination.
-------
ENVIRONMENTAL ASSESSMENT OF
STATIONARY SOURCE NOV CONTROL TECHNOLOGIES
/x
By:
H. B. Mason, E. B. Higginbotham, R. M. Evans,
K. G. Salvesen and L. R. Water!and
Acurex Corporation
Mountain View, CA 94042
163
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ABSTRACT
The "Environmental Assessment of NOV Control Technologies" (NO EA)
A A
was initiated in 1976 with the primary objectives to: a) identify potential
multimedia environmental hazards from stationary combustion sources under
both uncontrolled and controlled (for NOX) operation; b) develop control
application guidelines on the economic, energy, and operational impacts of
meeting prescribed emission levels, and c) identify the most cost effective
and environmentally acceptable NO control techniques to achieve and maintain
air quality standards. To address these goals efforts have been focused
toward ranking stationary combustion sources according to potentially
hazardous pollutant emissions, field testing to fill emissions data gaps,
impact analysis to estimate both the incremental impact of NOX control
application and the overall environmental hazard presented by stationary
combustion sources, and air quality analysis to provide a quantitative
basis for identifying future NO control needs.
A
This paper discusses results obtained to date in each of these areas.
The results of a multimedia emissions inventory for stationary sources is
presented and emissions projections to the year 2000 for various energy use
scenarios are discussed. Multimedia emissions data from a field test of a
180 MW tangential coal fired utility boiler are discussed. Analysis of
these data using a source analysis model suggest that the use of staged
combustion to reduce NO emissions results in an overall decrease in poten-
J\
tialfsource hazard. Estimated source population impact rankings for
stationary combustion sources are presented and discussed. Finally, results
of air quality analysis studies are presented in light of preferred controls
to meet current and projected N02 ambient air quality standards.
164
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ACKNOWLEDGEMENT
The work presented in this paper was performed under Contract 68-02-2160
to the U.S. Environmental Protection Agency, Industrial Environmental
Research Laboratory, Combustion Research Branch. The support and assistance
of Dr. J. S. Bowen and Messrs. R. E. Hall and R. P. Hangebranck is most
gratefully acknowledged.
The author would also like to thank the following individuals for
their gracious help and collaboration in efforts reported herein: H. Melosh
of Foster Wheeler Corp.; G. Bouton and S. Potterton of Babcock and Wilcox
Co.; G. Devine, C. Richards and J. Drenning of Combustion Engineering Co.;
F. Walsh and R. Sadowski of Riley Stoker Corp.; S. Barush of the Edison
Electric Institute; D. OelTAgnese of the Cleaver Brooks Division,
Aqua-Chem Corp.; W. Day of General Electric Co.; S. Mosier of Pratt and
Whitney Corp., J. Crooks and G. Hollinden of the Tennessee Valley Authority
and J. Thoraasian of EEA, Inc.
165
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SECTION 1
INTRODUCTION
In 1975, the Environmental Protection Agency increased its emphasis on
identifying and controlling potentially hazardous waste-stream discharges
from energy systems and industrial processes. This increased emphasis
resulted from recognition that a large number of multimedia (air, land,
and water) pollutants may be causing unacceptable environmental impacts.
Also, the energy supply shortage reenforced the need for coordinated energy
system development and environmental control development. In response, the
Industrial Environmental Research Laboratories of EPA started a major
Environmental Assessment (EA) program to guide environmental control develop-
ment and support standards setting and regulatory policy.
The "Environmental Assessment of Stationary Source NO Control Tech-
A
nologies" (NOV EA) was started in 1976 as one of over 20 EA's sponsored by
X
the Industrial Environmental Research Laboratories. The need for an EA of
NOX control technology was based on the increasing use of controls for which
the side effects are uncertain, and on the recognition that new advanced
controls will be needed to meet future emission standards and air quality
standards. The three primary objectives of the NO EA are to:
J\
• Identify potential multimedia environmental hazards from stationary
combusion sources
- under baseline operation without NO controls
J\
f - under low NO operation
X
0 Develop control application guidelines on the economic, energy
and operational impacts of meeting prescribed emission levels
t Identify the most cost effective and environmentally acceptable
NOX control techniques to achieve and maintain air quality considering
166
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- current and anticipated air quality standards
- alternate equipment use and fuel use scenarios to the year 2000.
The principal products of the NO EA are: rankings of potentially
A
hazardous pollutants for various source/control combinations; estimates of
costs and process impacts for existing and emerging control techniques for
each major stationary source; and rankings of NOV control techniques according
X
to their importance in air quality maintenance now and in the future. The
pollutant rankings are intended for use by EPA to identify control development
needs and as a data base for standards setting groups. The source/control
cost and process data are intended for control users and regulatory groups con-
cerned with selecting the best control for a specific application. The NOX
control rankings are used by EPA to set control development priorities so
that controls will be available when needed in the regulatory program.
Figure 1 shows the major NOV EA components (indicated by boxes) and
X
major products (indicated by ovals). The figure also notes the sections of
the paper where results are discussed. Results of the process engineering
effort are presented in another paper in this symposium proceedings
(Reference 1).
The program approach shown in Figure 1 is iterative. Initially, the
major program components were activated to help set program priorities and
to evaluate the need to develop assessment methodology. Subsequently, more
detailed effort has focused on generating new results and evaluating results
of other assessment activities. The chronological sequence of the program
is shown on Figure 2. Results from the early studies on source/control
priorities, emission characterization and impact models are documented in
References 2 through 5. These results are currently being refined and up-
dated. Interim results on process studies and the test program are documented
in Reference 6. The major reports for each source type on control applica-
tion guidelines and pollutant rankings from the test program are in the
draft stage. The first, for utility boilers will be published in Spring
1979 (Reference 7).
167
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SECTION 2
EMISSION CHARACTERIZATION
Emission characterization serves to rank emission sources and provide key
data base for impact analysis and air quality analysis. An emission inventory
was generated with the following features (Reference 3):
• gaseous, liquid and solid effluents
§ 42 equipment classes
• 17 fuel types
• NO , SOX, CO, particulate, trace metals, and polycyclic organics
rt
• nationwide and regional
• controlled and uncontrolled for NO , S0£, and particulate
• 1974, 1985, 2000
The approach is summarized below, and is shown as Figure 3.
NOV EMISSION INVENTORY
A
The emission factors, fuel consumption, and nationwide emissions for
the year 1974 are listed in Table I for the 120 equipment/fuel combinations
having significant NOX emissions. The emission factors were taken from field
test data and are revised as recent results become available. The fuel
consumption data are from Federal regulatory agencies and manufacturer trade
groups. These data are currently being updated to 1978.
NO emission rates summed by major equipment type and fuel type are
listed on Table II. The total annual nationwide emissions from all sta-
tionary sources sums to 12.0 Tg. This comprises 52 percent of total NOX
emissions, with mobile sources accounting for 9.6 Tg/yr. In Table II, the
"utility boilers" class includes all field erected watertube boilers with a
168
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heat input greater than 75 MW (250 MBtu/hr), while package boilers include
all industrial, commercial and residential boilers and hot water systems with
heat input below 75 MW (250 MBtu/hr). Conventional fossil fuel combustion
accounts for 94 percent of stationary emissions and utility boilers account
for 48.3 percent. In 1974, controls implemented for utility boilers gave
only a 3 percent NOX reduction nationwide relative to the uncontrolled util-
ity boiler estimate. The effect of controls is increasing, however, as
sources equipped to meet the 1971 New Source Performance Standard, 301 ng/J
(0.7 Ib N02/106 Btu), are brought on line. Although some controls were in-
stalled for gas turbines and nitric acid plants, the effect on nationwide
emissions was negligible.
A ranking of discrete equipment type/fuel type combinations by nation-
wide emission loadings is shown in Table III for the 15 highest emitters.
Here, the relative ranking is due both to the emission rates per source
and to the total installed capacity. Tangential coal fired utility boilers
rank first due to their high installed capacity - 11.3 percent of stationary
conventional fossil fuel consumption. Large spark ignition 1C engines rank
high due to their high emission rate: 10.5 percent of total emission vs
1.8 percent of fuel consumption. Similarly, coal fired cyclone utility
boilers rank fourth with 7 percent of stationary emissions while accounting
for only 3.5 percent of stationary fuel consumption.
The nationwide emission rates and source rankings for pollutants other
than NO are documented in Reference 3.
A
EMISSION PROJECTIONS
Emission projections to the year 2000 are highly uncertain due to the
uncertainty in fuels allocation by source and national energy policy. To
get upper and lower bounds on future NOX emissions, a high energy growth
scenario—based on continuation of future trends—and a low growth scenario
--based on the National Energy Plan—were used. The emission projections
for the two scenarios are shown on Figures 4 and 5. Two emission standards
scenarios are shown. The first assumes that no additional new source per-
formance standards would be set. The second, moderate scenario assumes
169
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standards will be set based on projections of emission levels achievable with
technology currently under development.
Under the high growth scenario with no additional standards total
emissions more than double by 2000 and stationary emissions more than triple.
The moderate NSPS scenario partially offsets the growth but stationary emis-
sions are projected to approximately double by 2000. Projected mobile source
emissions actually decline in the mid-1980's as current standards affect a
larger proportion of the auto population. Continued growth counterbalances
this in the 1990's however.
Under the low growth scenario with no additional controls projected,
total NOX emissions increase by 50 percent in the year 2000, with stationary
source emissions increasing by 70 percent. Stationary emissions growth is
suppressed to about 40 percent with moderate standards based on a contin-
uation of current R&D.
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SECTION 3
TEST PROGRAM
During compilation of the baseline emissions inventory discussed in
Section 2 and in a preliminary impact analysis of the incremental effects
of NO controls on pollutant emissions other than NO (Reference 2),
f\ A
numerous data gaps became apparent. Data on the effects of NO combustion
A
controls on emission levels of noncriteria flue gas pollutants and liquid
and solid effluents were virtually nonexistent. To address these data
needs a field test sampling and analysis program was conducted.
Based on the results of the preliminary source impact ranking performed
in the first year of the NO EA (Reference 2) a series of 19 candidate field
A
tests were identified. From the 19 potential tests, seven were selected
and tested. A summary of these seven tests is given in Table IV. Where
possible, the NO EA tests were done as an augmentation to planned or on-
/\
going tests.
For each test the following environmental assessment sampling protocol
was followed:
• Continuous monitoring of flue gas NOX, SOg, CO, C02, and 02
0 Flue gas Source Assessment Sampling System (SASS), EPA Method 5
particulate load, and EPA Method 8 (or equivalent) sulfur species
sampling; both upstream and downstream of the particulate collector,
if applicable
• Flue gas grab sampling and onsite gas chromatographic analysis
for C-J-C5 hydrocarbons; both upstream and downstream of the
particulate collector, if applicable
• Bottom ash slurry sampling
• Particulate collector hopper ash (slurry) sampling
171
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t Fuel and fuel additive, if applicable, sample collection
§ Operating data collection
As noted in Table IV, the test program was conducted, as a minimum,
for at least two conditions of source operation: baseline (uncontrolled)
and low NO operation. In several instances, operation at intermediate
J\
levels of NOX control was tested. In addition, replicate testing was per-
formed in selected cases.
A key part of the test program involved close monitoring of source
operating data. This was done not only to ensure that test conditions
remained constant and representative of acceptable source operation over
the duration of sample collection, but also to provide the necessary input
to further process analysis efforts.
Subsequent laboratory chemical analyses of samples collected generally
followed IERL-RTP Level 1 environmental assessment procedures (Reference 8).
Atomic absorption spectroscopy was employed to determine the concentration
of the 23 commonly occurring elements listed in Table V. The organic anal-
yses were extended, when feasible, to the determination of the 11 polycyclic
organic compounds (POM) listed in Table VI.
Following the EA analysis procedures, the following data could be
obtained for each test point:
t Continuous flue gas NOX, S02, CO, C02> and 0£
• Flue gas SOg, S03, and speciated C,-Cg hydrocarbon
t Flue gas particulate load and size distribution
t Flue gas vapor phase trace element composition for the 23 elements
listed in Table V
• Flue gas >C; organic composition in terms of seven compound polarity
fractions and flue gas POM composition for the 11 POM species listed
in Table VI
• Particulate composition for the 23 elements listed in Table V and
r the six ionic species listed in Table VII, as a function of partic-
ulate size
• Particulate organic composition for seven polarity fractions, and for
the 11 POM species listed in Table VI, as a function of particulate
size
t Liquid/solid stream (bottom, hopper ash) composition for the 23 elements
listed in Table V and the six ionic species listed in Table VII
172
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• Liquid/solid stream (bottom, hopper ash) organic composition for
seven polarity fractions and for the 11 POM species listed in
Table VI
• Parti oil ate and ash C and H content
t Fuel proximate and ultimate analysis (heating value, and water,
C, H, 0, N, and S content)
• Fuel trace element content for the 23 elements listed in Table V
In addition to the chemical analysis program, bioassay testing in
accordance with IERL-RTP Level 1 guidelines (Reference 9) were performed on
samples collected during the gas turbine, oil-fired utility boiler, second
coal-fired utility boiler, and second coal-fired industrial stoker tests.
The general bioassay protocol followed is indicated in Table VIII.
The field test program was completed in September 1978, and chemical
and biological analyses are nearing completion. As the analyses are
completed, they are combined with the process engineering results to give
the composite environmental, energy, efficiency, and operational impacts
of NO combustion modification controls.
X
The analysis results for the flue gas stream of a 180 MW tangentially
fired utility boiler are summarized on Table IX. Two levels of NOX reduction
were tested. Retrofit bias firing gave a 32 percent NO reduction, and
A
operation with the upper row of nozzles on air only gave a 38 percent NOX
reduction. The furnace efficiency either remained constant or increased
slightly (due to lower excess air) under low NOX operation. There was no
appreciable increase in carbon-in-flyash with NOX controls. It should be
mentioned that these tests were for short periods, so the long term oper-
ability under these low NO conditions was not necessarily validated.
J\
For the majority of elements listed in Table IX, the changes in emission
rates between baseline operation and low NOX firing were within the accuracy
of the analysis and are not judged to be significant. Notable exceptions
are the Teachable nitrates and ammonium compounds. Here, it is possible
that local fuel rich conditions under low NOX operation suppresses reduced
nitrogen compound oxidation normal to baseline operation.
The organics analyses yielded only general conclusions. Following
the prescribed environmental assessment sampling and analysis protocol,
173
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there was not a sufficient amount of organic material in any of the samples
to warrant fractionation by liquid chromatography. The mass spectral
analyses of the fractions resulting from the liquid chromatography were,
thus, not performed.
The general results of the organic analyses show that organic emissions
were slightly higher in the low NOV, burners out of service, test. The
A
organic material concentrations in the bottom ash, mechanical collector ash,
electrostatic precipitator ash, and the flue gas outlet (vapor phase) were
higher for low NOV firing. The flue gas outlet particulate organic content
/\
was slightly higher in the normal firing test. Although organic emissions
were low in these tests, there is a need to conduct more quantitative organic
analyses due to the relative hazards posed by certain organic compounds.
174
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SECTION 4
IMPACT ANALYSIS
Two pollutant impact models have been developed and applied. The first
is a single source analysis model (Reference 5) used to screen emissions
data and highlight those pollutant species emitted in sufficient quantity to
be potentially hazardous. The second model is a population exposure model
which approximates the hazard from all sources of a given type nationwide.
This model is used to rank sources on the basis of potential environmental
impact.
SINGLE SOURCE SCREENING MODEL
For purposes of screening pollutant emissions data to identify species
requiring further study, a Potential Degree of Hazard (PDOH) is defined as
follows:
pnnu - concentration of pollutant i- in effluent stream
u l "allowable effluent concentration
The "allowable" effluent concentration is, in general, the defined Threshold
Limit Value for the pollutant, which is the maximum pollutant concentration
considered safe for occupational exposure. When PDOH exceeds unity, more
refined chemical analysis may be required to quantify specific compounds
present.
To compare waste stream potential hazards, a Potential Toxic Unit
Discharge Rate is defined as follows:
PTUDR =(£) PDOH^) x Mass Flow rate,
•i
where the potential degree of hazard is summed over all species analyzed.
The PTUDR is an indicator of throughput of hazardous pollutants and can be
used to rank the needs for controls for waste streams.
175
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This model was applied to the analysis results for the 180 MW tangential
coal fired utility boiler discussed in Section 3. Table X lists the PDOH
values for those inorganic species or compounds where PDOH > 1 for one of
the three tests. It is evident that the gaseous pollutants, particularly
S02 and NOX dominate the potential toxicity of the flue gas stream. Of
the trace metals, arsenic shows the highest PDOH, but none of the metals
showed any Targe change under low NOX conditions. As may be expected, $03
decreased under low NOX operation and reduced N compounds increased.
The potential toxic unit discharge rate for the inorganic component
of four waste streams of the boiler are compared in Table XI. It is evident
that the flue gas stream dominates the PTUDR. Here, the PTUDR reduction
with biased firing and BOOS is primarily due to the decrease in NOX concen-
tration in the flue gas. The PTUDR's for the other waste streams either
decreased, or were constant when going to low NOX firing. As mentioned in
Section 3, more data are needed for waste stream organic composition before
the degree of hazard, relative to inorganics, can be estimated.
POPULATION IMPACT MODEL
To estimate population exposed to potentially hazardous pollutant levels
from stationary combustion sources, a population impact model was developed.
The impact model includes the following factors:
• Multipollutant emission estimates for each source type (NOX, SOX,
CO, HC, particulates, trace metals, polycyclic organics).
• Emission dispersion accounting for stack height and multiple area
sources.
t Population density in the source proximity.
• Estimates of permissible ambient concentrations.
• Ambient background concentrations.
An impact factor was defined as:
where*, P = population density,
x = ground level pollutant concentration,
176
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x. = ambient background pollutant concentration from other sources,
x = maximum permissible concentration, and
m
A = affected area as defined by the dispersion approximation.
Equation (1) was computed for a single source of each equipment/fuel type
and for each pollutant species. The impact factor was then summed over all
sources of a given type nationwide, and over all pollutant species from
each source.
Emission dispersion was approximated by a Gaussian plume model for
large point sources (Reference 10), and by a multi-source mixing model for
area sources (Reference 11). The spatial variations in population density
and ambient background were approximated by defining urban and rural regions
based on data from the US Bureau of Census and the National Emissions Data
System (NEDS). Equation (1) was calculated separately for each equipment/
fuel type in a rural area and in an urban area. The nationwide impact
factor was computed from estimates of the total capacity of each equipment
type which were in predominantly urban areas and in predominantly rural
areas.
The nationwide NO impact rankings, normalized to the highest ranking
source, are listed in Table XII for the top 17 sources. By comparison to
the emissions ranking in Table III, it is evident that several sources,
notably 1C engines, rank lower in impact than in emission loadings. This
is largely because these sources are located in rural areas where both
population density and ambient background concentrations are low. By con-
trast, in an urban area where the background concentration is a significant
percentage of the permissible limit, the presence of a large point source
can cause the limit to be exceeded over an extensive area.
The multispecies impact ranking, which includes species in addition
to NO and is shown in Table XIII, shows utility boilers with a much lower
overall ranking compared to the NOX impacts (Table XII). This is primarily
because the total multispecies impact is dominated by trace metals in the
particulate, and utility boilers are efficiently controlled for particu-
late emissions. Package boilers, however, are less efficiently controlled
and thus rank higher in estimated impact. As expected, coal and heavy oil
are responsible for the highest multispecies impacts.
177
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SECTION 5
AIR QUALITY ANALYSIS
The purpose of the air quality analysis is to provide a quantitative
basis for identifying the future needs (when, where, how much, and what
kind) for NO controls to satisfy the requirements of the Clean Air Act.
This information can then be used to recommend R&D directions and schedules
for developing necessary controls. In the air quality analysis, uncontrolled
emissions projections, controls cost and effectiveness data, fuel costs,
and ambient air quality goals are combined to evaluate the control needs for
a particular Air Quality Control Region (AQCR).
3
Currently the only NOV related ambient goals are the 100 yg/m annual
3
average for ML and a 160 yg/m 1-hour standard for oxidant. In addition,
the Clean Air Act amendments of 1977 require EPA to determine the need for
a short term NO^ standard. To date, no short term standard has been pro-
posed; although, EPA is known to be considering a 1-hour standard for NO,
o <-
between 200 and 1000 vg/m . Although we have considered both the oxidant
and potential N02 short term standards in our analysis, the primary focus
for the present discussion is the N02 annual average standard (Reference 6).
To allow us to examine a large number of growth/control scenarios for
a variety of AQCR's. we selected a modified form of rollback for an air quality
model. (The applicability of rollback for this type of analysis was somewhat
justified by two different analyses using the photochemical models LIRAQ and
DIFKIN (Reference 6)). This reduced the amount of emission data needed,
minimized computational costs, and provided maximum flexibility in the analy-
sis. Furthermore, only the N0x/N02 relationship was considered; thus, HC
emissions data collection was not required. The primary sources of emissions
178
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and fuel use data were the National Emissions Data System and the Federal
Energy Regulatory Commission (Federal Power Commission) annual reports.
In the rollback formulation employed it was possible to specify the
relative importance of each source type by using a source weighting factor.
Each choice of weighting factors is equivalent to choosing a different air
quality model for the AQCR. The utility of the model was further increased
by testing the sensitivity of the results to the input values. Control
strategies were developed for numerous combinations of stationary and mobile
source growth, base year calibration, and source weighting factors for each
AQCR. (These are briefly described on Tables XIV and XV.) This ensured
that the predicted control requirements would be responsive to the majority
of NO critical situations that might develop.
^
Over 20 different emissions growth/source weighting combinations for
eight AQCRs, listed in Table XVI, were considered. The eight AQCRs were
selected to represent a variety of source category, fuel use, and mobile/
stationary source mixes.
The variety of emissions source growth scenarios, mobile control
schedules, and AQCRs, resulted in predicted uncontrolled (no stationary
source controls beyond current NSPS) NO emissions changes relative to 1973
A
emissions of -6 percent to +3 percent in 1985 and of +5 percent to +50 per-
cent in 2000. The relatively small spread in 1985 emissions reflects the
relatively small impact of different mobile source control possibilities
between now and 1985. The very large spread in 2000 reflects the different
projected impacts from low stationary source growth with very strict mobile
control and high stationary source growth (~3 percent per year) with nominal
mobile growth and control compounded over 28 years.
Changes in ambient concentration corresponding to the above emissions
changes, ranged between -12 and +3 percent for 1985 and zero to +43 percent
in the year 2000. (The zero percent lower limit applies only to heavily
mobile dominated AQCRs with an extremely effective mobile control program.)
Since these results are from a variety of AQCRs, they are representative of
the range of expected change in ambient concentration for all AQCRs. These
calculated changes in ambient concentration do not exactly follow the
179
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percent changes in emissions since the use of the source weighting factors
in the air quality model can reduce or increase the impact of emissions
growth of selected sources.
The level of NO control required to offset the increase in ambient
/\
concentration depends on the initial value (1973) of the annual average NCL
concentration, the relative impact assigned to each source, and the mobile/
stationary mix. Based on results for all the AQCRs considered, a conservative
estimate is that at least four AQCRs will need significant application of
combustion modification NO controls to attain the annual average N02 stan-
dard by 1985. By the year 2000 this number will conservatively increase to
15, of which one-half would also need implementation of advanced controls
such as ammonia injection and possibly flue gas treatment. A 25 percent
increase in annual average fKL level by the year 2000 is most representative
of expected changes; therefore, any AQCR with a 1973 annual average greater
than 80 yg/m3 would exceed 100 yg/m3 by 2000.
Specific results from the matrix of control needs calculations for two
AQCRs are shown in Tables XIV and XV. The growth scenarios, source weight-
ing factors, and base year calibration for each case are shown in the
o
Tables. Control requirements to meet 100 yg/m or ambient levels, if less
3
than 100 yg/m , are shown for 1985 and 2000 for each case. The required NO
J\
control levels, indicated by 0, 1, 2, 3 and V, are described in Table XVII.
Controls are applied in the most cost-effective manner, and new controls are
introduced, if required, at the time (year) they are assumed to be developed.
The San Francisco AQCR is representative of those AQCRs which are not
currently nonattainment areas for NO- but which could become so in the
future. Emissions of NO in the region are heavily dominated by mobile
J\
sources (-70 percent). The results shown in Table XIV are representative
of mobile source dominated AQCRs with 1973 concentrations in the range of
2
75 to 100 yg/m . The dominance of mobile sources is clearly indicated by
the significant reduction in 1985 concentrations in all cases and by the
results for the low mobile cases in both 1985 and 2000. The results for the
high 6ase year concentration (BYR = 101 yg/m3) show that a mobile dominated
AQCR that is near nonattainment now will need the maximum amount of com-
bustion modification NO., control by the year 2000. Furthermore, if
180
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powerplants are not a significant contributor to the annual average (power-
plant weighting factor of 0.2), then even more NO control will be required.
/\
St. Louis is representative of an industrialized region dominated by
stationary sources (75 percent) with coal firing as a significant source of
NO (72 percent of stationary source NO is from coal-fired sources).
A A
Results for St. Louis are shown in Table XV. The relatively minor impact
of different mobile source growth and control scenarios is illustrated by
comparing the nominal growth and low mobile cases. Similarly, high station-
ary growth begins to have significant impact by the year 2000, even for the
low base year concentration (76 vg/m ). The difference in control require-
ments between mobile and stationary source dominated AQCRs is further
illustrated by comparison of the low base year cases for St. Louis and San
Francisco. The base year concentration is the same, but the ambient levels
or control requirements in the year 2000 are much different.
A significant feature of these results, which are typical of stationary
source dominated AQCRs, is that although no NO controls are needed in 1985,
J\
considerable NO control is required by the year 2000, even though the
X
present ambient level is well below the annual average standard.
It should be emphasized that these conservative estimates are used to
compensate for the extreme uncertainty in the monitoring data and the
inherent errors in the assumptions of the model. It should also be noted
that conservative growth rates and a successful mobile control program are
"built-in" to the estimates. All of this is to say that the above should
be considered an optimistic view of future NOV control needs to meet the
A
present annual average standard.
In addition to our investigation of NOV control requirements to meet
A
the annual average standard, we have also considered the impact of a one-
hour N02 standard (Reference 6). Recent studies performed by EPA have
shown that high short term N02 concentrations come about through any one of
several paths:
t Area source emissions (both mobile and dispersed stationary
sources)
181
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t Isolated point sources with multiple combustors impacting on a
single site
t Multiple point sources impacting on the same receptor
• Both area and point sources with all sources contributing to high
concentrations
• Terrain impaction by a plume from a large point source
The relative importance of these paths is highly dependent on both the
level which is established as the short term standard and the relative con-
tribution of each source type to the short term NOp levels. Moreover, the
NO
x
control requirements may be significantly different for each path.
Point source impacts were analyzed by modeling a series of prototypic
combustion plants ranging in size and operating parameters corresponding to
various source categories (e.g., utility boilers, industrial boilers, and
furnaces). The plants were analyzed individually, using a simple Gaussian
dispersion model and meteorological conditions associated with ground level
maximum N02, to assess the air quality impacts of all respective NO
sources in the NEDS file. Conversion of NO to N02 was approximated from
consideration of the time to maximum ground level impact and the background
N02 level, which was determined from N02 monitoring information within
individual AQCRs.
Area sources were analyzed by considering the available monitoring
data (Reference 12). All those AQCRs estimated to have current one-hour
N02 levels above 200 ug/m were included in the analysis.
Based on these two analyses, conservative estimates of the number of
AQCRs that would currently be in violation of various levels of a one-hour
N02 standard are: 1000 yg/m3 - 6, 500 pg/m3 - 30, and 250 ug/m3 - 120. By
1982 the estimated number of violators could slightly decrease, depending on
source growth and control. Beyond 1982 estimates are heavily dependent on
growth and control assumptions. Control requirements for attainment in
case of the above standards range from combustion modifications to FGT and
are yery site specific.
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Another aspect of the air quality analysis has considered the inter-
action of NO and HC controls on both NCL and ozone. Photochemical model-
ing results indicate that control of NO only does not provide as much
A
reduction in the NOp peak as simultaneous control of NO and HC. Further-
more, control of NO only aggravates the ozone problem for conditions like
A
those in many nonattainment areas for ozone. Any control strategy for NO
J\
must also consider HC control and the resultant impact on both short and
long term N02 levels, as well as the ozone levels.
183
-------
SECTION 6
SUMMARY
The preceding sections have discussed results obtained to date in
several related tasks of the N02 Control Technology Environmental Assessment
Program. In summary it can be concluded that:
t Based on a 1974 emissions inventory, stationary sources accounted
for 52 percent of nationwide NOX emissions. Utility boilers
contributed 48.3 percent of the stationary source emissions and
represented seven of the ten most significant emitter categories.
t Projections to the year 2000 indicate that, under a high energy
growth scenario with no emissions standards beyond the 1971 NSPS,
nationwide NOX emissions more than double and stationary source
emissions more than triple. Under a low energy growth scenario
with moderate promulgation of new standards stationary emission
growth is held to about 40 percent.
• Multimedia field test data on a 180 MM tangential coal fired
utility boiler indicate that applying staged combustion through
removing burners from service has neglibible effects on emission of
most pollutant species other than NOX. However, S03/S04= emissions
decreased and reduced nitrogen compound (Nfy*) emission increased
with low NOX operation.
• Application of a source analysis model to the utility boiler field
test data indicate that total potential source environmental impact
decreases under low NOX operation. Though not discussed above,
analysis data obtained in tests of an industrial stoker fired boiler
substantiate this conclusion.
t Results of an impact ranking taking into account installed capacity,
pollutant dispersion, and population density indicate that specific
utility boiler equipment categories represent the nine most potentially
hazardous stationary sources with respect to NOX emissions alone.
When trace metals, particulate, SOX, CO, HC, and polycyclic organic
r species are incorporated into the analysis stoker fired packaged
boilers displace utility boilers as three of the top ten most
potentially hazardous source categories.
184
-------
Air quality analyses suggest that the number of N02 nonattainment
regions will steadily increase, even with a highly successful
mobile control program. By 2000 at least 15 AQCR's will require
extensive application of combustion modification NOX controls and
several will require ammonia injection or FGT. Furthermore, a short
term N02 standard much less than 1000 yg/m3 would significantly
increase the requirements for NOX control.
The air quality analysis results also indicate that the impact of
any NOX control strategy on both N02 and ozone levels must be
carefully considered for each specific application.
185
-------
REFERENCES
1. Water-land, L. R., K. J. Lim and R. J. Schreiber, "Status of NOX Control
Implementation for Utility Boilers," paper presented at this Symposium.
2. Mason, H. B., e_t aK, "Preliminary Environmental Assessment of Combustion
Modification Techniques: Volume II, Technical Results," EPA-600/7-77-
119b, NTIS PB-276 681/AS, October 1977.
3. Salvesen, K. G., et al., "Emissions Characterization of Stationary NO
Sources," EPA-600/7-78-120a, June 1978. x
4. Waterland, L. R., et aj_., "Environmental Assessment of Stationary Source
NOX Control Technologies — First Annual Report," EPA-600/7-78-046,
NTIS PB-279 083/AS, March 1978.
5. Schalit, L. M. and Wolfe, K. J., "SAM/IA: A Rapid Screening Method for
Environmental Assessment of Fossil Energy Process Effluents," EPA-600/7-
78-015, February 1978.
6. Waterland, L. R., e_t a]_., "Environmental Assessment of Stationary Source
NOX Control Technologies -- Second Annual Report." In press.
7. Lim, K. J., et al_., "Environmental Assessment of Utility Boiler Com-
bustion Modification NO Controls," In press.
A
8. Hamersma, J. W., e_t al_., "IERL-RTP Procedures Manual: Level 1 Environ-
mental Assessment," EPA-600/2-76-160a, NTIS PB-257 850/AS, June 1976.
9. Duke, K. M., ejt al_., "IERL-RTP Procedures Manual: Level 1 Environmental
Assessment Biological Tests for Pilot Studies," EPA-600/7-77-043,
NTIS PB-268 484/3BE, April 1977.
10. Turner, D. B,, "Workbook of Atmospheric Dispersion Estimates," National
Air Pollution Control Association, 1969.
11. Holzworth, G. "Missing Heights, Wind Speeds, and Potential for Urban Air
Pollution throughout the Contiguous United States." Office of Air
Programs, U.S. Environmental Protection Agency, January 1972.
12. Thuilliers, R. W. and W. Viezee, "Air Quality Analysis in Support of
a Short-Term Nitrogen Dioxide Standard," Draft Report, SRI International,
December 1977.
186
-------
EmlMlon
CtwrKtorluUon
(Section 2)
00
Compw EmMMont
•nd Proem Dita
lor PrtocHy
(8MMon4>
HMtlhM*
Ecatogte*
Ootft
Moil effective
Control Option*
for Air Ouillty Godt
Figure 1. NOX EA program elements.
-------
1976
1977
1978
1979
1980
Goals:
Develop
Priorities,
Methodologies
Implement
Methodologies
Support
User
Needs
Implement
CCEA
Goals
Activities:
Emission
Characterization;
Impact Models
Tests,
Process
Studies
Impact
Assessments
Air Quality
Analysis
\
Updates &
Advanced
Technology
\
Results:
Source/
Control
Rankings,
Priorities
EA
Data
Base
Standards
Needs;
Application
Guidelines
R&D
Priorities
\
Updated
Standards &
Control
Needs
Figure 2. N0» EA chronological sequence.
-------
Develop emission
factors (uncontrolled,
controlled)
Define fuel
consumption
(nationwide, reoional)
Determine urban/
rural equipment
distribution
Controlled emission
inventory (1974)
National/reoional
baseline emissions
inventory (19/4)
Oetennine urban/
rural population
density
00
CO
Develop control
application
scenarios
Project emission
factors
Input data
for
Impact
analysis
Develop fuel
use scenarios
Project equipment
use distribution
Project fuel
consumption
Con trol1ed emt ss1on
inventory
(1985. 2000)
Figure 3. Emission characterization.
-------
Additional
Standards
derate NSPS
1974 1980 1985 1990 1995 2000
Figure 4. NO emission projections -
• A
high growth scenario.
40
30
20
10
Total
Mobile
j i i i
No Additional
Standards
Moderate NSPS
0
1974 1980 1985 1990 1995 2000
Figure 5. NOX emission projections -
low growth scenario.
190
-------
TABLE I. STATIONARY SOURCE FUEL CONSUMPTION AND NOX EMISSIONS - 1974
Equipment Type
Utility loiltrs
Packaged Bo 11 er»
Firing Type
Tangential Boilers
Hill Fired Boilers, Dry
Mill Fired Boilers, Met
Opposed Wall Boilers. Dry
Opposed Hill Boilers. Wet
Cyclone Boilers
Vertical I Stoker Boilers
U«ll Fired H-Tube >29.3 «*
Stoker U-Tube >W.3 »*
Single turner W-T <29.3 NX*
Fuel Type
Eastern Btlualn.
Central B1ti»1n.
Western BltuBtn.
Lignite
High S Res. 011
Ned S Res. 011
Low S Res. Oil
outturn on
Natural Gas
Cistern BHunin.
Central BUiOTln.
Western BUuBtn.
Lignite
High S Res. Oil
Ned S Res. Oil
Lou S Res. Oil
Distillate Oil
Natural Gas
Eastern BttiMin.
Central BUiwtn.
Western Bltu»1n.
Lignite
Eastern BltuMln.
Central Bitumln.
Western B1tu»ln.
Lignite
High S Res. 011
Ned S Res. 011
Low S Res. Oil
Distillate Oil
Natural Gas
Eastern BHunm.
Central BituBln.
Western BHj»1n.
Lignite
Eastern Sttunln.
Central Bttuain.
Lignite
High S Res. Oil
Ned S Res. Oil
Low S Res. Oil
Natural Gas
Anthracite
Eastern B1tua1n.
Central B1tu»1n.
Distillate Oil
Natural Gas
Process Gas
Slt/Llg Coal
Residual OD
B1t/L1g Coal
Distillate Oil
Natural Gas
Process Gas
Blt/Ltg Coal
Residual 011
Fuel Usage
(N)
2624.0
1&84.0
869.0
53.0
196.0
492.0
636.0
36.0
1134.0
1051.0
63S.O
348.0
S.O
196.0
493.0
637.0
169.0
2453.0
461.0
• 279.0
153.0
6.0
293.0
176.0
97.0
9.0
79.0
199.0
2S8.0
15.0
1258.0
130.0
78.0
43.0
12.0
156.0
1292.0
137.0
12.0
28.0
37.0
61.0
109.0
110.0
110.0
85.0
928.0
130.0
510.0
637.0
466.0
103.0
1690.0
130.0
317.0
595.0
Baseline
C*iss
-------
TABLE I. Continued
Equipment Type
Package* tollers
(Continued)
H«r*i Air
Furnaces
Gas Turbines
Reciprocating 1C
Engine
r
Firing Type
Scotch Firetube <29.3 W*
Flrebo* Firetube <29.3 ttf
Stoker Fired M-T <29.3 HI*
Cast Iron
Stoker F-T <29.3 »•
«T <29.3 *•
Res /Cow Stew I Hot Htter
War* Air Central Furnace
War* Air Space Heater
Miscellaneous Combustion
.Staple Cycle >15Wb
Sl«ple Cycle 4.0 to 15 *b
Staple Cycle <4.0Wb
C.I. >75k«/cylb
S.I. > 75 kM/cyl b
C.I. 75 kM to 75 k«/cylb
S.I. 75 KM to 75 k*/c/lb
S.I. <75 k«b
Fuel Type
Distillate 011
Natural Gas
Process Gas
Residual Oil
Distillate 041
Natural Gas
Process Cas
Residua! Oil
Anthracite
>1t/Llg Coal
DUt 11 lite Oil
Natural Cas
Residual Oil
Anthracite
Bit/llg Coal
Distillate 041
Natural Gas
Residual Oil
Anthracite
Distillate Oil
Natural Gas
IH/Llg Coal
Residual 011
Natural Gas
Oil
Natural Gas
Oil
Natural Gas
Distillate Oil
Natural Gas
Distillate 011
Natural Gas
Distillate Oil
Natural Gas
Distillate Oil
Dual (oil I gas)
Natural Gas
Distillate 011
Natural Gas
Gasoline
Gasoline
Fuel Usaoe
(N)
446.0
972.0
19.0
94S.O
403.0
899.0
19.0
609.0
31.0
1S33.0
181. 0
264.0
195.0
42.0
SS6.0
263.0
S3S.O
370.0
14.0
880.0
737.0
11.0
69.0
3091.0
1405.0
1451.0
727.0
1000.0
264.0
212.0
S79.0
468.0
1.0
1.0
54.0
70.0
813.0
129.0
43.0
84.0
49.0
last line
Emission
Factors
(nj *yj)
67.5
98.9
98.0
184.0
67.5
98.9
98.9
184.0
179.0
179.0
67.5
51.6
184.0
179.0
179.0
67.5
98.9
184.5
179.3
55.0
34.4
179.3
162.0
34.4
61.0
34.4
61.0
34.4
365.0
195.0
365.0
194.0
365.0
194.0
1741.0
1023.0
1552.0
1741.0
1552.0
119S.O
774.0
Total NOi
Emissions
(69 N0?)
30.1
96.1
1.9
173.9
27.2
88.9
1.9
112.1
3.8
274.4
12.2
13.6
35.9
7.5
99.5
17. B
52.9
66.3
2.5
48.4
25.4
2.0
11.2
106.3
85.7
49.9
44.3
34.4
96.4
41.3
211.3
90.8
.4
.2
94.0
71.6
1261.8
224.6
66.7
100.4
37.9
*Heat Input
bShaft output
CCI • compression Ignition; SI • spark Ignition
T957
192
-------
TABLE I. (Concluded)
Equipment Tj»p«
Ind. Process
CoBfeustlon
Firing Type
Ceaent Kilns
Gltss Melting Furnaces
Class Annealing lehrs
Coke Oven Under f1 re
Steel Sintering Machines
Open Hearth furnace (oil)
Irlck 1 Ceraatc Kilns
Cat Cracking (FCCU)
Refinery Fives
Iron I Steel Flares
Kef. HTB. Hat. Draft.
Hef. HTR. Mat. Draft.
«ef. HTR. For. Draft.
«ef. HTB. For. Draft.
Fuel Type
Processed Mat*
Processed Nat'
Processed Nat'
Processed Nat'
Processed Hat'
Processed Nat'
Processed Nat'
Processed Nat'
Processed Nat'l
Processed Nat'l
«4S
Oil
fas
Oil
Production
(Tg)
76.96
15.42
15.42
57.01
48.51
32.27
31.58
2294. Oa
7.8'
.3'
1119.0.
256.5*
128.2*
W.6*
Baseline
Emi ssi on
Factors
g/kg product
1.3
3.68
0.69
0.07
0.52
0.62
0.25
.2b
l.Od
1.0d
70. lf
154. 8f
no.5f
184. 5f
Total NOV
X
Emissions
(Gg M02)
xoo.o
56.7
10.6
4.0
25.2
20.0
7.9
45.9
7.8
0.3
78.4
W.7
14.2
14.9
*108t feed
bg/l fe«d
production Is not quantifiable, estimate of K)]| Is aa4« In fuel consumption coluan
*PJ
fng/J
T-9S7
193
-------
TABLE II. SUMMARY OF 1974 STATIONARY SOURCE N0xa EMISSIONS BY FUEL TYPE
Sector
Utility Boilers
Packaged Boilers
Harm Air Furnaces
Gas Turbines
Reciprocating 1C
Engines
Industrial Process
Heating
None ombust ion
Incineration
Fugitive
Total
NO Production Gg/yr
(X of total)
Coal
3810
(31.7)
781
(6.5)
—
~
—
—
~
—
—
4591
(38.2)
Oil
848
(7.0)
886
(7.4)
130
(1.1)
308
(2.6)
456C
(3.8)
--
—
—
—
2628
(21.8)
Gas
1156
(9.6)
779
(6.5)
190
(1.6)
132
(1.1)
1400d
(11.6)
—
—
—
—
3653
(30.4)
Total by
Sector
(X of total)
5810
(48.3)
?446
(20.3)
320
(2.7)
440
(3.7)
1856
(15.4)
426
(3.5)
193
(1.6)
40
(0.3)
498
(4.2)
12,029
(100.0)
Cumulative
(X)
48.3
68.6
71.3
75.0
90.4
93.9
95.5
95.8
100.0
*HO? basis
t £
Includes steam and hot water conmercial and residential heating
units
cIncludes gasoline
Includes dual fuels (oil and gas)
194
-------
TABLE III. NOX MASS EMISSION RANKING OF STATIONARY COMBUSTION EQUIPMENT
FOR 1974
en
Rank
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Sector
Utility Boilers
Reciprocating 1C
Engines
Utility Boilers
Utility Boilers
Utility Boilers
Utility Boilers
Utility Boilers
Reciprocating 1C
Engines
Utility Boilers
Packaged Boilers
Packaged Boilers
Packaged Boilers
Utility Boilers
Packaged Boilers
Packaged Boilers
Equipment Type
Tangential
>75 kM/cy1c
Hall Firing
Cyclone Furnace
Hall Firing
Hall Firing
Horizontally Opposed
75 kU to 75 kU/cylc
Horizontally Opposed
Uatertube >29 MUb
Uatertube Stoker <29 MM*
Uatertube >29 HUb
Tangential
Firetube Scotch
Uatertube <29 MWb
Fuel
Coal
Gas
Coal
Coal
Gas
Oil
Gas
01 ld
Coal
Gas
Coal
Oil
Oil
Oil
Gas
Annual
HOX (Mg)
1.410.000
1,262,000
1.137.000
848.300
646.800
458.300
352,200
325,000
324.500
318,500.
278,170
232.480
205.100
203.900
180.000
Cumulative
(Hg)
1.410.000
2.672.000
3.809,000
4,657.300
5.304.100
5.762.400
6.114,600
6.439.600
6,764,100
7,082.600
7,360,770
7,593,250
7.798.350
8,002.250
8.182,250
Cumulative'
(percent)
11.7
22.2
31.7
38.7
44.1
47.9
50.8
53.5
56.2
58.9
61.2
63.1
64.8
66.5
68.0
aN02 basis
bHeat input
cPower output
d Includes both distillate oil and gasoline
'Based on percent of total stationary source NOX emissions
T-958
-------
TABLE IV. NOv EA FIELD TEST PROGRAM
Source Category
Description
Coal-fired : 180 MH tangential; twin
Utility Boiler
furnace, 12 burners/
furnace, three eleva-
tions; cyclone, two
ESP's for participate
control
i
Coal -fired
Utility Boiler
500 MW opposed wall
fired; 24 burners,
three elevations;
ESP for particulate
control
|
Oil-fired
Utility Boiler
740 MW opposed wall
fired; 43 burners,
six elevations
Test Points
(Unit Operation)
Baseline
Biased Firing (2)
300S (2)
Baseline
BOOS (2)
.
Baseline
FGR
FGR + OFA
Sampling Protocol
Continuous NOX, S02, CO,
C02, Q2
Inlet to first ESP:
- SASS
— Method 5
— Method 8
Test
Collaborator
TVA
— Gas grab (C]-Cg HC) |
Outlet of first ESP:
- SASS
— Method 5
— Method 3
Bottom ash
Hopper ash (first ESP,
cyclone)
Fuel
Operating data
Continuous NOX, SOj,
CO, C02, 02
ESP inlet
— SASS'
— ftethod 5
— Method 8
-- Gas grab (Ci-Cg HC)
ESP outlet
-- SASS
— Method 5
— Method 8
— Gas grab (Ci-Cg HC)
Bottom ash
ESP hopper ash
Fuel
Operating data
Bioassay
Continuous NOX, SO?, CO,
C02, 02
SASS
Method 5
Method 8
Gas grab (Cl-Cfi HC)
Fuel
Operating data
Bioassay
Exxon
New test
start
196
-------
TABLE IV. Concluded
Source Category
Coal -fired
Industrial
Boiler
Coal -fired
Industrial
Boiler
Oil-fired
Gas Turbine
Oil-fired
Residential
Heating Unit
Description
Traveling grate
spreader stoker, 44
kg/s (350,000 Ib/hr);
ESP for particulate
control ; wet scrubber
for SOX control
Traveling grate
spreader stoker,
32 kg/s (250,000 Ib/hr)
ESP for particulate
control
60 MW GE MS 7001 C
machine
Blue Ray low NOX
furnace, Medford,
New York
Test Points
(Unit Operation)
Baseline
LEA + high OFA
Baseline
LEA + High OFA
Baseline
Maximum water
injection
Continuous
Cycling
Sampling Protocol
Continuous NOX, SOj, CO,
C02, 02
Boiler exit:
— SASS
— Method 5
— Shell -Emeryville
Test
Collaborator
KVB
— Gas grab (Ci-Ce HC) !
ESP outlet
— SASS
— Method 5
-- Shell -Emeryville
— Gas grab (Cl-Ce HC)
Bottom ash
Cyclone hopper ash
Fuel
Operating data
Continuous NO*, S02, CO,
C02, 02
Boiler exit:
— SASS
— Method 5
— Shell -Emeryville
— Gas grab (Ci-Ce HC)
ESP Outlet
~ SASS
— Method 5
— Shell -Emeryville
— Gas grab (Ci-Ce HC)
Bottom ash
ESP hopper ash
Fuel
Operating data
Bioassay
Continuous NOX, S02, CO,
C02, 02
SASS
Method 5
Method 8
Fuel
Water
Operating data
Bioassay
Continuous NOX, S02, CO,
C02, 02
SASS
Method 5
Method 8
Fuel
KVB
General
Electric
New test
start with
IERL/RTP
197
-------
TABLE V. ELEMENTAL ANALYSIS: SPECIES DETERMINED
Antimony (Sb)
Arsenic (As)
Barium (Ba)
Beryllium (Be)
Bismuth (Bi)
Boron (B)
Cadmium (Cd)
Chromium (Cr)
Cobalt (Co)
Copper (Cu)
Iron (Fe)
Lead (Pb)
Manganese (Mn)
Mercury (Hg)
Molybdenum (Mo)
Nickel (N1)
Selenium (Se)
Tellurium (Te)
Thallium (Ti)
Tin (Sn)
Titanium (Ti)
Vanadium (V)
Zinc (Zn)
TABLE VI. POM ANALYSIS: SPECIES DETERMINED
Anthracene
Anthanthrene
Benz(a)anthracene
Benzo(g,h,i)perylene
Benzo(ajpyrene
Benzo(e)pyrene
Coronene
Fluoranthene
Phenanthrene
Perylene
Pyrene
TABLE VII. ANION ANALYSIS: SPECIES DETERMINED
Chloride (CT)
Fluoride (F~)
Nitrate (N03-)
Cyanide (CIT)
Sulfate (S0i2-)
Ammonium (NH4+)
198
-------
TABLE VIII. BIOASSAY ANALYSIS PROTOCOL
Sample Type
Bioassay Test Protocol
Sample Size
Requirements
SASS cyclones,
3u
co
CO
SASS cyclones,
ly + filter
XAD-2 extract
Bottom ash
ESP Hopper ash
Microbial Mutagenesis
Cytotoxicity, WI-38
Microbial Mutagenesis
Cytotoxicity, WI-38
Microbial Mutagenesis
Cytotoxicity, RAM
Microbial Mutagenesis
Cytotoxicity, WI-38
Rodent Acute Toxicity
Freshwater Algal Bioassay
Freshwater Static Bioassay
Microbial Mutagenesis
Cytotoxicity, WI-38
Rodent Acute Toxicity
Freshwater Algal Bioassay
Freshwater Static Bioassay
l.Og
0.5g
l.Og
0.5g
50
50
l.Og
0.5g
lOOg
50 kg
(200 I if
sluiced)
l.Og
0.5g
lOOg
50 kg
-------
TABLE IX. ANALYSIS RESULTS FOR A TANGENTIALLY COAL-FIRED UTILITY
BOILER: FLUE GAS, INORGANICS
Test
Heat Input (% of baseline)
Emissions y£
m3 dry
N0x(ppm £ 3% 02 dry)
S02(ppm @ 3% 02 dry)
S03(ppm @ 3% 02 dry)
CO ftpm 0 3% 02 dry)
co2(%)
o2 (%}
Particulate
Antimony
Arsenic
Barium
Beryllium
Bismuth
Boron
Cadmi urn
Chromium
Cobalt
Copper
Iron
Lead
Manganese
Mercury
Molybdenum
Nickel
Selenium
Tellurium
BASELINE
100
1.16xl06(490)
4. 1 8x1 06 (1668)
1.45x10^(3)
3. 07x10^(28. 6)
2.72xl08(13.9)
(5.2)
6.3xl05
3.9
95
2.25xl03
9.0
<44
-
<1.8
1.69xl03
66
2.8xl02
4.5x10"
74
2.4xl02
1.8 <3.1
1.5x102
S.OxlO2
9.9
< 4.1
BIAS (test 1)
100.9
7.35xl05 (336)
3.5xl06 (1354)
1.32xlO*(3)
4. 58x1 OM 35.0)
2.82xl08(14.4)
(4.7)
6.7xl05
<2.6
77
1.7xl03
11
<55
-
<2.4
4.7xl02
75
3.3xl02
3.3x10"
86
1.3xl02
<0.06
< 55
2.6xl02
3.0
< 4.0
BOOS (test 2)
92.4
6.54xl05(304)
4.21xl06(1591)
9580 (3)
3.19x10^(21.7)
2.86xl08(14.6)
(4.4)
4.3xl05
<2.6
81
1.5xl03
7.2
2.3xl02
8.7xl02
<2.1
2.4xl03
89
3.2xl02
3.3x10"
61
1.9xl02
3.5< 5.5
8.7xl02
1.5xl03
< 2.1
< 3.7
200
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TABLE IX. Concluded
Thallium
Tin
Titanium
Uranium
Vanadium
Zinc
Zirconium
Chloride
Fluoride
Cyanide
Nitrate
Sulfate
Arrmonium
Coal Analysis
C%
H%
0%
N%
S%
H20%
Ash%
HHV Btu/lb
BASELINE
< 2.6
< 6.4
6.1xl03
< 3.9
2.6xl02
4.2xl02
2.7xl02
2.7xl02
84
< 1.3
< 3.9
6.5xl03
< 5.3
63.13
4.27
7.34
1.38
2.19
2.04
19.60
11302
BIAS (test 1)
< 2.7
< 6.7
5.7xl03
7.5
2.3xl02
4.3xl02
2.6xl02
4.1xl02
3.5xl02
< 0.3
< 26
3.9xl03
7.2
63.46
4.24
7.97
1.13
1.75
2.34
19.09
11334
BOOS (test 2)
< 3.2
< 5.1
3.6xl03
< 2.1
1.6xl02
2.0xl02
6.8xl02
8.5xl02
1.2xl02
< 1.3
7.7xl02
2.1xl03
1.4xl02
64.00
4.23
7.11
1.38
2.13
2.58
18.49
11402
201
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TABLE X. FLUE GAS POTENTIAL DEGREE OF HAZARD - INORGANICS;
180 MW TANGENTIAL COAL-FIRED UTILITY BOILER
NO
X
so2
so3
CO
co2
Be
Ba
As
Ti
M (Mainly NH4)
so4
Chlorides
BASELINE
129
322
15
0.77
30
4.5
4.5
48
1
0.07
6.5
0.68
BIAS
84
269
13
1.1
31
5.5
3.4
39
0.95
0.22
3.9
1
BOOS
73
324
9.6
0.80
32
3.6
3.0
41
0.60
6.1
2.1
2.1
TABLE XI. POTENTIAL TOXIC UNIT DISCHARGE RATES (g/s) - 180 MW
TANGENTIAL COAL-FIRED UTILITY BOILERS - INORGANICS
Flue Gas
Cyclone Ash
ESP Ash
Bottom Ash Slurry
BASELINE
4.3xl07
1.9x10"
e.ixio3
5.7x10"
BIAS
3.5xl07
1.6X101*
6.1xl03
5.3x10*
BOSS
3.7xl07
1.6x10"
5.1xl03
4.2x10"
202
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TABLE XII. NOY IMPACT RANKING FOR STATIONARY SOURCES
Rank
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Sector
Utility Boilers
Utility Boilers
Utility Boilers
Utility Boilers
Utility Boilers
Utility Boilers
Utility Boilers
Utility Boilers
Utility Boilers
Reciprocating
1C Engines
Utility Boilers
Package Boilers
Package Boilers
Gas Turbines
Package Boilers
Gas Turbines
Reciprocating
1C Engines
Equipment Type
r«clone
Tangential
Horizontally Opposed
Horizontally Opposed
Wall Firing
Wall Firing
Horizontally opposed
Hall Firing
Tangential
SI»>75 kW/Cylb
Tangential
Wall Firing WT<* >29 MWC
Wall Firing WT<*>29 M«c
Simple Cycle >15 MHb
Wall Firing WT<* >29 MWC
Simple Cycle >15 MW&
Cie >75 kW/cylb
Fuel
Coal
Coal
Coal
Gas
Coal
Gas
Oil
Oil
Oil
Gas
Gas
Gas
Oil
Oil
Coal
Gas
OiJ and
Dual Fuel
Normalized NOX
Impact Factor
1.0
0.895
0.51
0.39
0.37
0.31
0.19
0.19
0.15
0.10
0.077
0.059
0.057
0.049
0.046
0.048
0.016
aSpark ignition
"Energy output
cHeat input
dWatertube
j:- ?on ignition
T-1523
203
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TABLE XIII
TABLE XIII. MULTISPECIES IMPACT RANKING FOR STATIONARY SOURCES
Rank
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Sector
Packaged Boilers
Packaged Boilers
Utility Boilers
Utility Boilers
Packaged Boilers
Packaged Boilers
Utility Boilers
Utility Boilers
Utility Boilers
Utility Boilers
Utility Boilers
Utility Boilers
Packaged Boilers
Packaged Boilers
Packaged Boilers
Utility Boilers
Packaged Boilers
Equipment Type
Stoker Firing MTC<29 MWa
Stoker Firing FT<*<29 MWa
Tangential
Hall Firing
Wall Firing WTC>2g MWa
Stoker Firing WTC>29 MH*
Vertical and Stoker
"Cyclone
Horizontally Opposed
Tangential
Hall Firing
Horizontally Opposed
Hall Firing WTC>29 MWa
Scotch FTd<29 MW«
Firebox FT«J<29 W«
Tangential
Scotch FTd
Fuel
Coal
Coal
Coal
Coal
Coal
Coal
Coal
Coal
Coal
Oil
Oil
Oil
Oil
Oil
Oil
Gas
Gas
Normalized
Impact Factor
1.00
0.83
0.21
0.16
0.12
0.11
0.085
0.061
0.031
0.0039
0.0033
0.0017
0.0010
0.0008
0.0005
0.0005
0.0004
»Heat input
bHeat output
c«atertube
dFiretube
T-1524
204
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TABLE XIV. SUMMARY OF CONTROL LEVELS REQUIRED TO MEET THE ANNUAL
AVERAGE N02 STANDARD IN SAN FRANCISCO, AQCR (030)
Case
Nominal Growth*
Low Mobilef
High Stationary?
BYR* = 76 ug/m3
Ppb = 1.0 PP = 0.5 PP = 0.2
MSC =1.0 MS = 1.2 MS = 1.0
0(67)5
0(60),
'0(66)
0(75)
K85)
0(69)
''Of 81)
0(68).
3(82)
BYR = 101 ug/m3
PP = 1.0 PP = 0.5 PP » 0.2
MS =• 1.0 MS = 1.2 MS * 1.0
0(79L
'0(88)
0(100)
0(74)
0(91)
0(75),
'0(84}
0(90)
T-1293
TABLE XV. SUMMARY OF CONTROL LEVELS REQUIRED TO MEET THE ANNUAL
AVERAGE N02 STANDARD IN ST. LOUIS, AQCR (070)
Case
Nominal Growthe
Low Mobilef
High Stationary9
76 ug/m3
ppb , LO PP = 0.5 PP - 0.2
MSC =1.0 MS =• 1.2 MS = 1.0
0(80)
0(79)
0(76)
0(70),
3(84)
0(80)
BYR = 85 ug/m3
PP = 1.0 PP » 0.5 PP = 0.2
MS = 1.0 MS = 1.2 MS = 1.0
0{B2j,
^0(95)
0(90)
0(84
0(79),
0(88)
0(85)
^0(94)
0(92)
T-1292
— Base year ambient concentration for calibration
bpp — Powerplant weighting factor
CMS — Mobile source weighting factor
^Numbers in parentheses indicate annual average concentration in yg/m3. If no number
given, annual average equals or exceeds 100 yg/n>3.
eStationary source growth less than historical, mobile sources grow at 3.5%/yr, 0.62 g/km in 1981
^Stationary source growth less than historical, mobile sources grow at l.OX/yr, 0.25 g/km in 1985
9Stationary source growth at approximately historical rates, mobile sources grow at 3.5J£/yr, 0.62
g/kro in 1981
205
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TABLE XVI. AQCR'S INVESTIGATED FOR NOX CONTROL REQUIREMENTS
Los Angeles (024)
Chicago (067)
Philadelphia (045)
New York City (043)
Denver (036)
San Francisco (030)
Pittsburgh (197)
St. Louis (070)
Low -- Recorded
Annual Average NO,
Ug/m3) *
1972 - 1975
132
96
83
99
88
76
62
76
High — Rolling
Quarter Average NO,
(ug/m3j <•
1972 - 1975
182
121
121
113
110
101
98
85
TABLE XVII. DEFINITION OF STATIONARY SOURCE NOX CONTROL LEVELS
Level'
• No controls (assumes 1971 NSPS for large boilers
is met)
• 40-80 percent control of new residential and
commercial furnaces
• 6-16 percent control by low excess air for
industrial and utility boilers
• Staged combustion, flue gas recirculation,
low-NOx burners and other advanced designs for
boilers
• Operating adjustments and new design for 1C
engines
• Water injection for gas turbines (30% reduction)
• Ammonia injection for boilers (50% reduction
beyond level 2 controls)
• Combustion control limits exceeded, flue gas
treatment required
"Control levels are ordered by increasing cost of the controls. Within
each level controls are applied in order of increasing cost.
206
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AN OVERVIEW OF THE CONVENTIONAL COMBUSTION
ENVIRONMENTAL ASSESSMENT PROGRAM
By:
Deepak Kenkeremath
METREK Division
MITRE Corporation
McLean, Virginia 22102
207
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ABSTRACT
The conventional combustion of fossil fuels for heat and electricity
production has been the foundation of today's industrialized society. In
fact, over 90 percent of the total U.S. energy needs are still met by fossil
fuels. The associated environmental effects of conventional combustion
processes, however, are significant and span across the air, water, and land
media. These multimedia effects are not separate and distinct, but rather are
all interrelated, defining a systemic problem. The scientific and managerial
approach to solving such problems has to be by necessity comprehensive and
holistic in nature.
The Conventional Combustion Environmental Assessment (CCEA) program,
sponsored by the Industrial Environmental Research Laboratory in Research
Triangle Park (IERL-RTP), North Carolina, is designed to comprehensively
identify and assess the total environmental effects of combusting fossil fuels
in all conventional processes. The program integrates ongoing and planned
R&D activities into a coherent and unified environmental assessment structure.
The overall goals of this program are aimed at providing a base of sound
information for use by energy/environmental decision-makers for:
• Standards Development
• Control Technology Development
• Energy/Environmental Policy Formulation
• Allocation of Resources
The program currently consists of a defined set of program goals and
objectives, an explicit methodology for conducting a comprehensive environ-
mental assessment, an analytical procedure to identify, evaluate, and integrate
the programmatic contents of Individual projects, and a management structure
to administer the program. The CCEA program currently consists of six
projects. The paper will describe the above items and will discuss support
given to EPA standard-setting program offices by the CCEA outputs.
208
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SECTION 1
INTRODUCTION AND BACKGROUND
It is not a mere cliche to say that the world of today is quite
different from that of yesterday. Whereas most of human history has focused
on technological solutions to the problems of the world as we found it, the
critical issues of today and tomorrow involve the problems of the world as
our technology has made it. In fact, it is the very success of yesterday's
technological solutions that has led to the critical problems of today and
tomorrow.
A classic example of such a problem is the degradation of the environ-
ment resulting from the use of fossil fueled combustion technologies. The
development of reliable fossil-fueled combustion technologies has been the
foundation of today's industrialized society. In fact, approximately 95
percent (about 70 x 10 ^ Btu) of the total U.S. energy needs are still met
by fossil-fueled combustion. Conventional methods of converting fossil fuels
to usable energy forms, however, have been a significant source of deleterious
environmental impacts. The release of sulfur dioxide from conventional com-
bustion of coal and oil, for example, is a direct cause of increased acidity
in rainfall. Carbon dioxide, another major byproduct of conventional com-
bustion, has the potential to seriously affect the world climate by contri-
buting to the so-called "greenhouse" effect. In addition, the introduction
of toxic heavy metals such as cadmium and arsenic, and potentially carcino-
genic organic compounds such as polycyclic organic matter (POM) into the
ground and surface waters as an indirect result of conventional combustion
technologies pose serious threats to human health. Control of the environ-
mental impacts from conventional fossil-fueled combustion is one of the
major problems facing us today.
209
-------
The scientific, engineering, and managerial approach to this environ-
mental problem has to be, by necessity, quite different from the traditionally
reactive, single objective, viewpoint of past research. The conventional
combustion of fossil fuels has multimedia impacts which affect the air, land,
and water. Furthermore, these impacts are not separate and distinct; rather,
they are all interrelated and involve delicate balances and tradeoffs.
From the scientific point of view, it is essential to identify and
understand the environmental relationships that exist between the many orders
of indirect impacts. For example, the disposal of fly ash from coal-fired
power plants has a direct impact on the land quality of the disposal sites.
Leaching of chemical compounds and heavy metals from the disposal sites has
an indirect (second-order) impact on the quality of the ground and/or surface
water. This in turn may have third-order impacts on the ecology of the area.
It is important to identify all direct and indirect impacts. Another major
scientific aspect is the multi-pollutant synergistic impacts on human health
and the environment of the various pollutants emitted by conventional combus-
tion systems. For example, although polycyclic aromatic hydrocarbons (PAH)
are generally toxic, their potency as carcinogens is enhanced by their
preferential adsorption on small particles of certain materials such as iron
oxide. A similar synergistic intensification may exist between fine particles
and sulfur dioxide.
From the engineering point of view, an important concept in dealing with
technologically induced environmental problems is the concept of cross-
impacts. Since the environment is esentially a closed system, technology to
control one pollutant or media has some relative cross-impact on another
pollutant or media. For example, flue gas scrubbing to remove SO^ and
particulates significantly increases the amount of solid wastes to be
disposed of in an environmentally acceptable manner. The secondary environ-
mental impacts caused by pollutant control technologies themselves are an
important engineering problem.
The management of environmental R&D efforts to identify and assess the
full health and ecological implications of conventional fossil-fueled
combustion must also be approached in a comprehensive and unified manner.
210
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In addition to evaluating the full range of relationships that exist among
environmental impacts, communication with environmental control technology
development and emission standard setting activities must be closely main-
tained. The programmatic efforts of these three general areas must be
properly coordinated to ensure effective and efficient solutions to the
environmental problems.
The Environmental Protection Agency, the lead Federal organization
responsible for the identification and control of adverse environmental
impacts of pollutant emissions,is aware of the importance of conducting such
environmental studies in a holistic, coordinated manner. This awareness
has led to the development of major comprehensive assessment programs in
such emerging energy technology areas as coal liquefaction, low/medium btu
gasification, high btu gasification, and fluidized-bed combustion. Since
these technologies are still in the development or demonstration stage, EPA
is investigating all potential environmental problems now to ensure that
they will have minimal health and ecological impacts when they are fully
commercialized.
In the area of conventional, fossil-fueled combustion process, however,
existing wide-spread use of the technology precludes a completely proactive
environmental assessment prior to commercialization. The majority of the R&D
efforts to date have been narrowly defined and reactive in nature, involving
such issues as identification of emissions from particular processes,
evaluation of the effects of specific compounds, or development of technology
to control single pollutants. While data generated by these various efforts
provide an important base of information, a full assessment of the environ-
mental effects of conventional fossil-fueled combustion processes is still
necessary.
211
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SECTION 2
OVERALL CCEA PROGRAM STRUCTURE
In response to this need, the Environmental Protection Agency's
Industrial Environmental Research Laboratory at Research Triangle Park
(EPA/IERL-RTP), North Carolina, established the Conventional Combustion
Environmental Assessment (CCEA) program. Initiated in early 1977, the CCEA
is chartered to assess comprehensively the environmental, economic, and
social impacts of multimedia emissions of pollutants from conventional
combustion processes, and to recommend measures for controlling adverse
effects within acceptable limits. The program utilizes information generated
by past studies and integrates relevant ongoing and planned R&D efforts into
an overall environmental assessment structure, coordinates their activities,
and serves as a centralized base of information. The CCEA is designed to be
both reactive in addressing immediate problems and proactive in undertaking
research to identify and recommend solutions to other major environmental
problems that may be anticipated in the future.
OBJECTIVES AND SCOPE
The principal objectives of the CCEA program are to identify and assess
information from all relevant sources in order to:
(1) determine the extent to which available information can be
utilized to assess the total environmental, economic, energy
impacts of stationary conventional combustion processes.
(2) identify and acquire additional information needed for such
assessment.
(3) define the requirements for modifications or additional
development of control technology.
(4) define the requirements for modified or new standards to
regulate pollutant emissions.
The results of the CCEA program are aimed at providing a base of sound
information for use by energy/environmental decision-makers for:
212
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• Standards Setting
• Control Technology Development
• Policy Formulation
• Resource Allocation
Although the program is comprehensive in its approach and subject matter,
there are some major boundaries that shape and focus the efforts of the
program. The scope of the CCEA program can be briefly delineated as follows:
• The program is concerned with stationary conventional combustion
processes and is focused principally on equipment and combustion
processes used in the utility, industrial, commercial/institutional,
and residential sectors.
• The program addresses environmental effects that result directly
from the operations of the combustion process itself, as well as
those that result from the operation of equipment to control the
release of pollutants from the combustion process, such as leachate
from fly ash impoundment basins.
• The program addresses non-environmental criteria such as social,
economic, and political/institutional effects.
• The program also addresses environmental effects from the
conventional processing and storage of fuels at the combustion
site, such as the crushing of coal at a power plant.
• The program does not address the effects of fuel processing and
storage prior to delivery to the combustion site, or during
transportation of the fuel.
• The program addresses environmental effects of utilizing synthetic
fuels in conventional combustion equipment.
• The program does not address the environmental effects of converting
fossil fuels to synthetic fuels, whether performed at the combustion
site or elsewhere; thus, it does not include consideration of the
impacts of low-btu gasification of coal when the gasification
equipment is within the battery limits of the power plant where the
gas is burned.
• The program is not directly involved in design or development of
combustion processes or pollution control technologies.
• The program is not directly involved in the setting or enforcement
of emission standards.
COMPONENTS OF THE PROGRAM
The overall CCEA program structure currently consists of four major
interrelated components:
213
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(1) A defined set of long term CCEA program goals and intermediate
term objectives.
(2) An explicit methodology to conduct a comprehensive environmental
assessment of conventional combustion processes.
(3) An active set of seven major ongoing projects.
(4) A defined management structure to implement the program.
Each of these four CCEA program components are discussed briefly below.
Goals and Objectives
As discussed earlier, the overall aim of the CCEA program is: (1) to
assess comprehensively the effects upon human health, the ecology, and the
general environment of utilizing fossil fuels in stationary conventional
combustion processes, and (2) to recommend measures for controlling adverse
effects within acceptable limits.
Consistent with EPA mission, the principal use of environmental
assessment information produced by the CCEA program will be to aid managerial
decision making relative to environmental standards and pollution control
technology development. In terms of this principal use, the program's long-
term goals are more explicitly stated as follows:
• To assess the adequacy of existing technology to control the
release of pollutants from stationary conventional combustion
processes.
• To assess the need for modifications to existing control technology
or for the development of new control technology and, if such needs
exist, providing guidance and recommending priorities for the tech-
nology development effort.
• To assess the adequacy of existing emission or effluent standards
designed to limit the release of pollutants to the environment.
• To assess the need for additional standards or modification of
existing standards and, if such needs exist, providing guidance
and recommending priorities for EPA's standard setting activities.
Supporting each of these goals are several intermediate objectives,
most of which correspond to the outputs of various tasks or subtasks of
the CCEA program and thus constitute useful products that will be developed
during the coarse of the program.
214
-------
The key technical and administrative objectives have been identified and
categorized as follows:
Combustion Process/Pollutant Characterization Objectives
• Develop a unified, comprehensive base of existing data on
combustion pollutants.
• Obtain essential new data from field tests.
• Characterize emissions/effluents from each major type of stationary
conventional combustion process.
Health/Ecology/Environmental Impact Assessment Objectives
• Estimate quantities of pollutants released from stationary
conventional combustion processes.
• Identify available models and other effects-estimating techniques.
• Develop quantitative estimates of health, ecological, and environ-
mental effects (including associated economic costs) of pollutant
emissions.
• Define priority areas for health/ecological/environmental impact
studies.
Technology and Information Transfer Objectives
• Determine information needs of current/potential users of environ-
mental assessment information.
• Transfer technical information to appropriate user organizations in
a timely manner.
Control Technology Development Objectives
• Develop a comprehensive data base on the capabilities of existing
technology to control the release of combustion pollutants to the
environment and on the costs of applying such technology.
• Identify specific combustion processes and specific combustion
pollutants for which additional control technology capability is
needed to meet current standards.
Standards Development Objective
• Identify specific combustion processes and specific combustion
pollutants for which modified or new standards are needed to limit
pollutant emission/effluents to acceptable levels.
These goals and objectives are discussed in more complete detail in
References 1 and 2.
215
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Environmental Assessment Methodology
An environmental assessment (EA) is a special category of holistic
investigative study that resulted from the growing awareness of the direct
and indirect consequences of modern technology. In particular, an environ-
mental assessment is defined here as an iterative procedure to develop a
basis for ranking environmental problems and control needs. The iterative
procedure involves:
• Determination of comprehensive environmental effects and control
costs associated with various control options for specific sources,
processes, or industries; and
• Comparison of the effects with existing standards, estimated
environmental goals, and anticipated health impacts.
Within the context of the CCEA program, this definition includes socio-
economic and institutional effects, and cross-media impacts and tradeoffs,
in addition to the environmental loading data, control costs, disposal
options, bioassay specifications, and other factors included in the above
definition. It must be emphasized, however, that environmental
assessment activities of the CCEA" program do not involve either the develop-
ment or promotion of the combustion process or the development or promotion
of technology to control emissions from the combustion process.
The overall procedure involves the following steps to be performed for
each type of combustion process. The interrelations among these steps are
shown diagrammatically in Figure 1. (This procedure, presented here in
highly condensed form, is expected to be further refined and applied to
major stationary conventional combustion processes over a period of about
five years.)
Step 1. Characterization of Combustion Process (and Related Pollution
Control Equipment) and Its Emission/Effluents.
For each principal type of combustion process the characteristics
of fuels, control technology, and measurement/analytical techniques
are identified. In particular, it identifies the quantities and
characteristics of emissions and effluents.
Step 2. Identification of Health, Ecological, and Environmental Effects of
Emissions/Effluents from the Combustion Process.
This step includes the identification of transport and transfor-
mation of the specific pollutants in the ambient environment, and
216
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anticipated response of the ecology and the exposed population in
terms of morbidity/mortality rates, media degradation factors and
other appropriate measures. Such factors must take into account
background levels of pollutants from noncombustion sources.
Step 3. Development of Environmental Goals and Objectives
In the initial stages of this program, goals will be defined
principally in terms of established standards or unofficial
permissible media concentrations. In later stages, the set of
goals may be expanded to include such factors as the promotion
of a specific energy policy or direction of economic development.
Step 4. Comparison of Health/Ecological/Environmental Impacts of
Stationary Conventional Combustion Processes Against Environ-
mental Goals and Objectives
This comparison indicates whether established standards are ueing
met, and other defined goals and objectives are being achieved.
This comparison may have three outcomes. (1) If it indicates that
standards are, in fact, met and other goals and objectives have been met
or can reasonably be expected to be achieved by ongoing R&D activities
relating to the combustion process under study, then the EA procedure is
completed for this process. (Repetition of the procedure is required for
other processes.) (2) If there is some question of whether goals and
objectives are being achieved, it may then be necessary to repeat the above
three steps, possibly using better data or more precise analyses (see
Figure 1). (3) If the comparison indicates that goals and objectives are
not being achieved, then the EA procedure is continued as follows:
• Determine the Magnitude of Pollution Impacts from the Combustion
Process
Quantities of pollutants released from continued use of stationary
conventional combustion processes at projected levels, ambient levels
of such pollutants at appropriate geographic scales, and the degree
of hazard (severity indices) associated with continued use of the
combustion process are estimated.
• Evaluation of Alternative Control Strategies for Achieving Goals
and Objectives
Strategies that will contribute toward achievement of goals and
objectives may include development of more effective pollution
control technology or the use of other alternatives such as fuel
switching and modification of combustion techniques; alternatively,
the strategy may be to modify the existing standards or other goals/
objectives.
217
-------
This last step would indicate alternative approaches for meeting defined
goals and objectives (e.g., suggested new technological or non-technological
approaches for controlling pollutants from the combustion process under
study); hence, it provides new input for iterating the entire EA procedure.
Iterations may be required for each viable alternatives identified.
The comprehensive EA methodology is a complex and lengthy procedure
which is described above only in general outline. Additional detail for
the major steps in the procedure are indicated in Figure 2 and a more
detailed description of the entire procedure is presented in Reference 3.
It should be noted that the comprehensive EA methodology described
here is based in substantial measure on an EA methodology developed by the
Energy Assessment and Control Division (EACD) of IERL-RTP. The EACD
methodology has undergone extensive development and has gained widespread
acceptance in the technical community. The relationship between the CCEA
comprehensive EA methodology and prototype procedure developed at IERL-RTP
is discussed in Reference 3.
Current Projects Within Program
The CCEA program currently includes seven major technical projects.
Three of these projects were already ongoing when the CCEA program was
established. Appropriate parts of these projects have been properly inte-
grated into the program. The other four were initiated later to assist in
planning, coordinating, and implementing the CCEA program. Each of these
projects is briefly described below. A more detailed discussion, including
project results will be given by the other speakers at this session.
• SURVEY OF PROJECTS CONCERNING THE ENVIRONMENTAL ASSESSMENT OF
CONVENTIONAL COMBUSTION PROCESSES
EPA Project Officer: Wade Ponder
Contractor: Research Triangle Institute
Term: March 1977 - May 1978 (initial phase only)
This project was initiated at approximately the same time as the
initiation of the CCEA program planning effort. The project was undertaken
in an effort t(ji identify and evaluate major relevant R&D studies ongoing at
that time within EPA, within other Federal organizations, and within non-
government organizations. The major objectives of this project are to:
218
-------
• Summarize information related to the CCEA program on a national
basis.
• Determine the significance and utility of the information in meeting
CCEA program objectives.
• Organize the survey information in a convenient format for sub-
sequent use in the CCEA program.
The preliminary results of this survey were instrumental in the development
of the CCEA program plan.4
• DEVELOPMENT OF A PROGRAM FOR THE ENVIRONMENTAL ASSESSMENT OF
CONVENTIONAL COMBUSTION PROCESSES
EPA Project Officer: Wade Ponder
Contractor: Metrek Division/The MITRE Corporation
Term: February 1977 - June 1980
This is a major management and program planning project that was
initiated to assist in formulation of the overall CCEA program structure.
The major objectives of this project are to:
• Develop a coherent, unified methodology for assessing the environ-
mental, economic, and energy impacts of continued and expanded use
of stationary conventional combustion processes
• Define long-term goals and short-term objectives for the CCEA
Program
• Develop analytical procedures to identify, evaluate and integrate
CCEA related activities
• Provide assistance in procuring a CCEA systems contractor
• SYSTEMS ENGINEERING SERVICES FOR THE CCEA PROGRAM
EPA Project Officer: Wade Ponder
Contractor: Not identified at time of printing
Term: February 1979 - February 1981
The systems contractor will be the focal point in implementing the
technical aspects of the CCEA program. This project will coordinate with
the others to work within the previously established CCEA program plan to
achieve stated goals and objectives. The major objectives of this project
are to:
• Assess the effects of combustion pollutants on human health,
ecology, and the general environment
• Evaluate the adequacy of existing technology to control the release
of pollutants from Stationary Conventional Combustion Processes
219
-------
• Assess the need for modification of additional control technology
• Assess the need for the development of additional control technology
• Evaluate the adequacy of existing emission or effluent standards
• Assess the need for the modification of existing standards
• Assess the need for the development of new standards
• ENVIRONMENTAL ASSESSMENT OF STATIONARY SOURCE NO CONTROL TECHNOLOGIES
(NO EA) X
A
EPA Project Officers: Joshua S. Bowen, Robert E. Hall
Contractor: Acurex Corporation
Term: June 1976 - September 1979
The NO EA project was undertaken in response to the critical need to
X
evaluate the environmental, economic, energy, and engineering implications
of combustion modification technologies to control NO emissions. The over-
all goals of this project are: (1) to identify the multimedia environmental
impacts of stationary combustion sources and NO combustion modification
controls, and (2) to identify the most cost-effective, environmentally-
sound combustion modification NOX control systems for attaining and maintain-
ing current and projected NO air quality standards to the year 2000.
• EMISSIONS CHARACTERIZATION OF CONVENTIONAL COMBUSTION SYSTEMS
EPA Project Officers: Warren Peters, Wade Ponder
Contractor: TRW
Term: October 1976 - June 1980
This is a major CCEA project designed to address the "Combustion Process
and Effluent Characterization" step of the environmental assessment methodology.
The primary goal of this project is to develop extensive baseline data by
identifying and characterizing the gaseous, liquid, and solid pollutants
generated by fifty-one specific categories of uncontrolled stationary con-
ventional combustion processes. These categories include the combinations
of eight different combustion processes utilizing ten different fuel types
in the four major use sectors of utility, industrial, residential, and
commercial/institutional. Emissions data are being obtained through the
use of the EPA Level 1 and Level 2 comprehensive sampling and analysis
protocol. The final output of this project will include estimates of
total pollutant emissions by each category of uncontrolled combustion
process.
220
-------
• COMPARATIVE ASSESSMENT OF OIL VS. COAL FIRING IN CONTROLLED INDUSTRIAL
AND UTILITY BOILERS
EPA Project Officer: Wade H. Ponder
Contractor: TRW
Term: March 1977 - December 1978
One of the most important types of information needed for technological
and policy decision making is the relative environmental impacts of firing
coal vs. oil in well-controlled industrial and utility boilers. (Here,
"well-controlled" implies the use of appropriate methods of reducing emissions
of S0? and particulate matter to meet applicable emission standards for these
pollutants.) Such information would facilitate the formulation of policy
pertaining to fuel use and fuel switching, and would provide technologists
with useful data on control technology performance.
This project is an important effort in developing a data base on well-
controlled combustion processes. The project was initiated at approximately
the same time period as the CCEA program planning effort.
The overall objectives of the project are to:
• conduct a comprehensive multimedia emissions assessment of oil vs.
coal firing in both industrial and utility boilers
• evaluate efficiencies and effects of control devices for the
boilers tested, and
• assess the environmental, energy, and social impacts on firing
coal vs. oil.
These objectives are being met through field tests of selected industrial
and utility boilers. The sampling and analysis includes both combined
Level 1 and Level 2 sampling and analysis protocol.
• ENVIRONMENTAL ASSESSMENT FOR RESIDUAL OIL UTILIZATION
EPA Project Officer: Sam Rakes
Contractor: Catalytic, Inc.
Term: May 1976 - May 1979
Residual oil from refinery reject streams offers a potentially signifi-
cant source of fuel for electric utility and industrial applications. This
project is a three-year effort to identify and assess the environmental con-
sequences of the production and utilization of residual oil in combustion
processes. Control options such as fuel desulfurization and FGD are also
221
-------
included in this study. Although the majority of the funds are currently
being spent in the areas of fuel treatment and chemically active fluid bed
technology, a significant portion of the technical effort involves gas
turbine technology and FGD technology.
The major objectives of the project are to:
• review and analyze the existing environmental, engineering,
and cost data;
• identify important pollutants and their projected attainable
emission levels;
• identify missing information and design a program(s) to develop
such information; and
• design and conduct source sampling, fugitive emission and ambient
monitoring programs.
Program Management Structure
The overall CCEA program is currently managed by the Process Technology
Branch (PTB) within lERL-RTP's Utility and Industrial Power Division (UIPD).
Although some of the projects are sponsored by other divisions within IERL-
RTP, the technical and budgetary portions of the environmental assessment
activities are managed by UIPD.
The major functional groups in the CCEA management structure are shown
in Figure 3. The day-to-day management of the overall program is the
responsibility of the CCEA program manager and his staff. The program
manager coordinates the activities among the various projects and acts as
the key link between the technical and management aspects of the program.
The Steering Committee (SC) will serve as an advisory group to the IERL
Director on the overall direction and conduct of the CCEA program. In
addition, it will provide oversight guidance to the Technical Working Group
(TWG) in the coordination of CCEA activities. Further examples of duties include
such things as recommending allocation of resources (CCEA versus other programs)
and recommending redirection of program/project emphasis as needed.
Cooperative program solving across organization lines will be the goal
of the TWG and £he SC. The SC will attempt to resolve, by consensus,
problems/issues which result from impasses in the Technical Working Group.
222
-------
The resolution of such problems/issues will be passed to the TWG for
implementation in the program. Problems which the SC cannot resolve in this
manner will be elevated to the IERL Director for final resolution. These
major responsibilities are outlined on Table 1.
The Technical Working Group will review, coordinate and serve as
the forum for the working level activities of the CCEA program and its
component projects requiring group coordination. Since the CCEA program
components cut across current organizational lines, it is important to
establish an accepted functional framework within which the TWG can perform
its duties.
The TWG is made up of IERL Branch Chiefs and Project Officers who are
directly involved with component projects in the CCEA program. The TWG,
chaired by the Chief of the Process Technology Branch, will conduct CCEA
activities requiring coordination of program components at the TWG level.
It is anticipated that the majority of CCEA issues will be resolved at the
TWG level, but it is important to note that TWG members can individually or
collectively take unresolved problems directly to the UIPD Director. Further,
if his decision is not acceptable to the parties involved, they can seek
elevation of the problem to the Steering Committee through their respective
Division Directors who are members of the Steering Committee. Major
responsibilities of the TWG are outlined in Table I.
The TWG functional framework described above permits continuation of
the CCEA program within the existing IERL organizational structure. CCEA
projects remain in their respective Divisions and, existing organizational
lines of communication remain intact and unchanged. In addition, the UIPD
Director has the responsibility to attempt resolution of TWG problems
before elevation to the full Steering Committee. The Steering Committee
has the responsibility to attempt resolution prior to elevation to the
IERL Director.
223
-------
SECTION III
CCEA SUPPORT TO EPA PROGRAM OFFICES
Consistent with the Environmental Protection Agency's primary role as
a regulatory organization, one of the principal purposes of the CCEA is to
provide technical support for developing emissions and effluents standards.
Specific types of informational support regarding such subject areas as
combustion process descriptions, emissions/effluents characterization,
transport/transformation/fate of pollutants, health/ecological effects,
national and regional effects, control technology performance, and
economics are essential in setting priorities and formulating standards
and regulations.
Research to develop this information is specifically designed into
the EA methodology of the CCEA program. Also designed into the CCEA
management structure are channels for communications and information
exchange with potential users. An important effort currently (at the time
of publication of this paper) being undertaken is the identification of
specific data needs of EPA Program Offices and a comparison of projected
CCEA outputs with these needs. This comparison will provide useful guidance
in focusing, developing, and implementing future activities within CCEA.
A preliminary effort under this "applicability analysis" activity is
the comparison of projected CCEA outputs with data requirements to fullfil
legislative mandates. Although the effort is not completed (at the time
of publication) an example of a partially completed comparison matrix is
shown in Tables II and III. Table II is a partial draft showing projected
CCEA program support for the development of seven New Source Performance
Standards (NSPS). Similarly, Table III shows a partially completed draft
of CCEA program support for developing National Ambient Air Quality
Standards (NAAQS). It is emphasized that these tables are preliminary and
224
-------
partial and are included here only to exemplify the matrix after it has
been completed.
These applicability matrices, along with similar matrices covering
other legislative mandates are currently being reviewed with the Office
of Air Quality Planning and Standards (OAQPS), Office of Water and Waste
Management (OWWM), and the Office of Solid Wastes (OSW) to ensure complete-
ness and accuracy. Future activities under this effort will include the
identification and comparison of general data needs of EPA Program Offices,
EPA Enforcement Offices, and technology development divisions within the
Department of Energy.
REFERENCES
1. Kenkeremath, D. C., C. J. Miller, and J. B. Truett, A Program for the
Environmental Assessment of Conventional Combustion Processes, EPA-
600/7-78-140, July 1978.
2. Kenkeremath, D. C., C. G. Miller, and J. B. Truett, A Program for the
Environmental Assessment of Conventional Combustion Processes, M78-63,
Mitre Corporation, July 1978.
3. Ponder, W. H. and D. C. Kenkeremath, Conventional Combustion
Environmental Assessment Program, M78-44 Rev. 1, Mitre Corporation,
September 1978.
4. Thompson, W. E. and J. W. Harrison, Survey of Projects Concerning
Conventional Combustion Environmental Assessments, EPA-600/7-78-139,
July 1978.
225
-------
STEP1
CHARACTERIZE COMBUSTION
PROCESSES AND EFFLUENTS
ITERATE
FOR EACH
ALTERNATIVE
STRATEGY
to
CO
o>
STEP 2
IDENTIFY HEALTH, ECOLOGICAL
AND ENVIRONMENTAL EFFECTS
i 1
REFINE
DATA BASE
AND ANALYSIS
STEP 4
STEP 3
DEVELOP ENVIRONMENTAL
GOALS AND OBJECTIVES
MAYBE
STEP 6
ASSESSMENT
COMPLETED
STEP 5
EVALUATE ALTERNATIVE
CONTROL STRATEGIES
ASSESS MAGNITUDE OF
POLLUTION IMPACTS
RECOMMENDATIONS FOR:
- NEW/REVISED STANDARDS
- CONTROLTECHNOLOGY DEVELOPMENT
Figure 1 - Comprehensive Environmental
Assessment Methodology
Principal Steps
-------
to
CO
-a
CUMtUSTION PROCESS TECHNOLOGY DOM-RESPONSE DATA
CHARACTERISTICS , Thr.M»oNJ iml. ntoMlTLVl
* Preceai economle
• Energy ellklency
Type and *ourc«
Physical eharaclerlaik*
Chemlcel charwterletM:*
Energy content
Fuel handling
AvalUbWty ot luel*
_„„ L. „:
STEP 1 I?,0"","'?!.'
"1
ANALYSIS TECHNIQUES
• Sampune lechnlojuea
• Analytic letthnlqua*
• Cancei anal Mmfcemle
INPUT-OUTPUT CHACTER1ZATION ECOLOQICAL IMPACTS
• Miierlal balance • Ecology related Impact*
1
FATI MODELS
• Meteorological and hydrologlcel
date
• Model devetopflient
* Sipoaure level eakulatton*
• Tremloonallofl chemtetry
*
•OH BK» AMD 1 ( ||11|M1. _^l HEALTH AND BCOLQQICAL | STEP 2
* ' 1 *
FIELD TESTS AND SURVEYS 1 EP10EM 10 LOGICAL DATA
• Centre! tyttemt iMltouj . indtntry related hearth datl
• Level i
• Level)
f
SIOASSAY DATA
• Conlrol pfeceaa itream Meaaaey
-_ I J" REPINE DATA IASE
CONTROL STRATEGY ENVIRONMENTAL
IMPACTS
• Weeia dlapoui option*
VoooiMani a ,'*'|™ impac a
Croit media w»ptr*a
CONTROL ALTERNATIVES
• Add-«n devteoa
• Coetbtnllen medllkallon
1 ALTtMNATrVCCOHTHOL |»£ltH °
DEVELOPMENT RECOMMENDATIONS
• Conitol lechnotogy modttleationa
• Quantified R»D r*aed«
• Criteria tor prtorllte*
STATUTORY CONSTRAINT*
• Fetfera'/tiare ilantfartf* antf
regWatl»ni
• RoMircfi data baea lot
•landird*
I
1 ENVIRONMENT
OBJECTIVES
f
AMBIENT POLLUTANT LEVELS
• Dili «J)«tNw »nd evaluation
' COMBUSTION MOCKS
USE PROJECTION*
• Currant market ette
* Future nwrtet pmMKittoni
^
EMISSION OR AMBIENT
LEVEL GOALS
• Permlielble media concentration
• Criteria lot e«tabtt*hlng
pfUKllUt
• Control lechnoMgy ItrnH*
• MATE
t
AL GOALS AND 1 CTca -
KVELOPMENT | altr^ J
f
SOCIAL/ECONOMIC /POLITICAL/
INSTITUTIONAL CONSIDERATIONS
• NonpoHutant Impact goal*
(energy, aoclel. economic, etc.)
• OuenlMIwi nonpollutani impact*
• SWng crHvrle
* Crrthtal malarial* Impecta
STEP 4
T^^ lM*comb«*1MriiproceM
NO
TOTAL POLLUTANT
LOAD CALCULATIONS
• Proceea loading.
• Other Murce* loedhg
• Natural bechground
1
1 MAGNITUDE OF 1 CTCD ,
r~
POLLUTANT PRIORITY
MMKINO
• Total polrutint loed
• Degree ot hai ard
(•evenly Indicet)
REGIONAL GEOGRAPHIC
DATA
• Demographic S land uaa
pattern* A trend*
• Hydrologrand
R.D M» .y...m RECOMMENDATION, IMPACTS
Damonalratlon teal* lyalam • Standard* medHteetlofll • Multimedia pollutant
Economkt * Sl*n4erdi dev*4epmen< Ottrtbutlan foatfi
Energy requirement* • Criteria 1* prk««t** • Additive. lran*lorma«o«,
PoMulent removal elllciency • Tlmelreme and enhancement effect*
•ouice analyw* m
odel*
-------
IERL DIRECTOR
UIPD
DIRECTOR
l
I
to
CO
CD
CCEA STEERING COMMITTEE
'CHAIRMAN, UIPD DIRECTOR
EACD DIRECTOR
IPD DIRECTOR
IERL DIRECTOR'S REPRESENTATIVE
CCEA COORDINATOR
CCEA TECHNICAL WORKING GROUP
CHAIRMAN, PrTB CHIEF
EA BRANCH CHIEFS
EA PROJECT OFFICERS
CCEA COORDINATOR
SUPPORT CONTRACTOR (MITRE AT
PRESENT)
Figure 3 - CCEA Functional Management
Structure
-------
TABLE I
CCEA MANAGEMENT RESPONSIBILITIES
to
(S3
TECHNICAL WORKING GROUP
• Develops and recommends CCEA Program
scope, funding and schedules for approval
of Steering Committee
• Prepares draft accomplishment plans
• Prepares and presents program review
materials
• Recommends correction of program/project
emphasis as needed to the Steering
Committee
• Resolves routine problems/issues
• Elevates other problems/issues to UIPD
Director Steering Committee resolution
• Meets quarterly to discharge its
responsibilities although special meetings
will be called on an ad hoc basis as
necessary
STEERING COMMITTEE
• Advises IERL Director concerning CCEA
Program
• Reviews annual CCEA Program plans
• Recommends allocation of resources—
CCEA versus other programs
• CCEA program reviews
• Reviews and evaluates CCEA Program
outputs
• Corrects program/project emphases as
needed
• Recommends resolution of problems
raised by working group
• Meets at the request of the members—
approximately twice per year
-------
Partial Draft Showing CCEA Program Support for NSPS Development
-^ STANDARDS UNDER CONSIDERATION
~\ BY OAQPS
CCEA "--
TECHNICAL FROJECT&--^__^^
STATIONARY SOURCE NO,
CONTROL TECHNOLOGIES
(ACUREX CORPORATION)
DIISSIOSS CHARACTERIZATldil
OF CONVENTIONAL
COMBUSTION SYSTHB
(TRW)
10
O9
o
SYSTEMS ESCIk'EERING
SiRVlCES FOR.CCEA
(CONTRACT BEING
XECOTIATED)
Internal Combustion
Engine Control
Technology
(CAA-1U)
P-2/79.-P-2/80
Task 5.4 - Control
Engineering &
Environmental
Impact Assessment
of 1C Engines
Task 2 - Multimedia
Pollutant! assess-
ment of 1C Sources
for Electric Power
Generation * Steam
Task 1.1- Pollu-
tant characterisa-
tion (primary &
secondary) and
. control levels
terisUcs of Pollu-
tant Emlsslona fron
Specific Sources
Task 2.2 - Idcn-
tificcx ton of
types of stationary
conventional com-
bustlon processes'
not adequately
characterized
Task 3.2 - Total
National Erolaeion*
of Combustion
Pollutants by
Source
Task 4.2 - Capa-
bility and coata
of Control Tech-
nologies to
meet existing
& Proposed
Federal
Standards
Tall Stacks
Regulations
(CAA-112)
P-9/78;F-2/»
Task 1 - Multi-
media pollutant*
assessment of
stationary con-
ventional com-
bustion processes
Task 1 1 - Pollu-
tant characteriza-
tion (primary &
secondary) and
control level!
nioues for
Quantifying
Health/Environ-
mental Effects
of Combustion
Pollutants
Task 4.2 - CapablHt
technologies to neat
existing and propose
Federal standard*
Gas Turbines
(NOX Emission!)
;F-2/79
Task 5.5 - Control
Engineering &
Environmental
Impact Assesament
of Gas Turbine*
Task 2 - Multimedia
Pollutants assess-
ment of Internal
Combuatlon Source*
for Electric Power
Generation and
Steam
Task 1.1 - Pollu-
tant chnracterlze-
tion' (primary &
secondary) and
control levels
Task 3.2 - Total
National Emiealon*
of Combustion
Pollutants by
Source
) Task 4,3 -
Prioritized listing
for Modifying
c Existing Control
Technologies or
for New Technology
Development
Incinerator*
Task 3 - Multi-
media Pollutants
assessment of other
sources for Electric
Power Generation
and Steam
Task 1.1 - Pollu-
tant characteriza-
tion (primary &
secondary) and
control levels
Task 2.0 - Charac-
teristics of Pollu-
tant Emissions from
Specific Sources
Task 4.2 - Capability
and costs of control
technologies to meet
existing and proposed
Federal atanderd*
Utility Boiler*
(Revised)
;F-3/79
Task 5.1 - Control
Engineering &
Environmental
Impact Assessment
of Utility Boilers
Task 3 - Multimedia
Pollutants assess-
ment of other sources
for Electric Power
Generation I Steaa
tant characteriza-
tion (primary &
secondary) and
control levels
Task 3.2 - Total
National Emissions
of Combustion
Pollutants by
Source
Task 4.3 -
Prioritized listing
for Modifying
Existing Control
Technologies or
for New Technology
Development
Industrial
Boilers
(Revised)
P"10/SO;F-8/81
Task 3 - Multimedia
Pollutants assess-
ment of other
sources for Electric
Power Generation *
Steam
Task 5 - Mul ti-
med 1 /i Pollutants
assessment of
Industrial
Combustion Source*
tant characteriza-
tion (primary &
secondary) and
control levels
Task 4.3 -
Priori tlzed
Us ting for
Modifying Existing
Control Technologies
or for New Tech-
nology Development
Waste Fuel
Boilers
tant characteriza-
tion (primary t
secondary) and
control levels
T.iKk ;.3 - Plan fnr
acquiring missing
Data en _char.irte-ris-
tics of Pollutant
frnisfilons
TpsV 3.2 - Total
N.iLion.-il r.nl'.alons
cf Cor.nnstlon
Pollutants by
Source
Task 4.3 -
Prioritized listing
for Modifying
Existing Control
Technologies or
for New Technology
Development
-------
TABLE II
Partial Draft Showing CCEA Program
Support for NSPS Development (Continued)
~^STANDARDS UNT5ER CONSIDERATION
' — — -^^^ BY OAQPS
CCEA ' — ^^^
IF.CHN1CAL PROJECTS -^____^^
COMPARATIVE ASSESSMENT OF
COAL VS. OIL FIRING
IN WELL-CONTROLLED
INDUSTRIAL 6
UTILITY BOILL'RS
(TRW)
CO
00
1— '
ENVIRONMENTAL ASSESSMENT OF
RESIDUAL OIL UTILIZATION
(CATALYTIC CORPORATION)
Internal Combustion
Engine Control
Technology
(CAA-111)
P-2/79;F-2/80
Tall Stack*
Regulation*
(CAA-1121
P-9/78;F"2/79
Tesk 4 - Assess-
ment of control
technology for
Residual Oil
Processes
Task 5 - Environ-
mental Alternatives
assessment (con-
vs. Pollutant
Priorltlzatlon)
Cas TurbinM
(NOX Emissions)
JF-2/79
Incinerators
'
Utility Boilers
{Revised)
;F-3/79
Task 1.2 - Multi-
media emissions
utility boilers
Task 2,2 - Environ-
of coal & oil
firing in Utility
Boilers
Task 3.2 - Com-
parative emissions
assessment
Task <>. 2 - Compara-
tive Energy & Social
Impacts of Coal
vs. Oil for
Utility Boilers
Task 1 - Multi-
media Environ-
mental Goals,
including TLV's,
existing S pro-
posed standards
& NSPS
Task ft - Future
Research needs
(including
for pilot or
demonstration
plane scale)
1 Industrial
Boilers
(Revised)
P-10/80;F-8/81
T^isk 1.1 - Multi-
media emissions
trial boilers
Task 2.1 - Envlron-
of coal & oil
firing in Indus-
trial Boilers
Task 3.1 - Com-
parative emissions
assessment of coal
vs. oil for
Industrial Boilers
Task 4.1 - Compara-
tive Energy & Social
Impacts of Coal
vs. Oil for
Industrial Boilers
T.isk 2 - Multi-
media Environ-
mental Goals,
including TLV's,
existing & pro-
posed standards
t SSPS
Tnsk 6 - Future
Research needs
(including
for pilot or
demonstration
plant scale)
Wast* Fuel
Boilers
i
i
i
1
I
i
-------
TABLE III
Partial Draft Showing CCEA Program Support for NAAQS Development
STANDARDS UNDER CONSIDIMTICH
BY OAQPS
CCEA TECHNICAL PROJECTS
ENV1ROIMEXTAL ASSESSMENT
OF STATIONARY SOURCE HO,
CONTROL TKC«::OLOGIES
(ACL REX CORPORATION)
CO
CO
to
EMISSIONS CHARACTERIZATION
OF CONVENTIONAL
'COMBUSTION SYSTEMS
(TRW)
Review of Long Tarm
NAAQS for NO,
(CAA-108)
P-l/79;F-6/79
Tank fi -
Identification of
cost Affective
and environmen-
tally sound NOX
Control System.
Task 1 - Multimedia
ment of Residential
Sources
Task 2 - Multi-
media Pollutants
assessment!! of 1C
Sources for
Electricity Power
Generation & Steaa
Task 3 - Multimedia
fflent of other com-
bustion sources for
Electricity Power
Generation & Steam
Task 4 - Multimedia
ment of Commercial/
Institutional
Sources
Task 5 - Multimedia
Pollutants assess-
ment of Industrial
Combustion Sources
Development of
short t«rm NAAQS
for N02 (CAA-109)
F-12/78;F-6/79
Task 2 - Multi-
media NOX
Emission Impact!
A Adequacy of
Data
Task 4 -
Evaluation of
NOX Sampling
Techniques
Task 6 -
Identification of
cost effective
and environmen-
tally sound NOX
Control System.
Task 1 - Multimedia
aent of Residential
Sources
Task 2 - Multi-
media Pollutants
assessments of 1C
Sources for
Electricity Power
Generation & Steam
Task 3 - Multimedia
ment of other com-
bustion sources for
Electricity Power
Generation & Steam
Task 4 - Multimedia
ment of Commercial/
Institutional
Sources
Task 5 - Multimedia
Pollutants assess-
ment of Industrial
Combustion Sources
Review of MAAQS for
photochemical
oxidanta
F- 12/78
Task 2 - Multi-
media M0x
Emission Impacts
& Adequacy of
Data
Task 4 -
Evaluation of
N0x Sampling
Techniques
Review of NAAQS for
CO
P-4/79;F-7/79
Taak 1 - Multimedia
Pollutants assess-
ment of Residential
Sources
Task 2 - Multi-
media Pollutants
assessments of 1C
Sources for
Electricity Power
Generation & Steam
Task 3 - Multimedia
ment of other com-
bustion sources for
Electricity Power
Generation & Steam
Task 4 - Multimedia
ment of Commercial/
Institutional
Sources
Task 5 - Multimedia
Pollutants assess-
ment of Industrial
Combustion Sources
Review of NAAQS tor
S0x
P"5/80;F-12/80
Taak 1 - Multimedia
ment of Residential
Sources
Task 2 - Multl
media Pollutants
assessments of 1C
Sources for
Electricity Power
Generation 4 Steam
Task 3 - Multimedia
ment of other com-
bustion sources for
Electricity Power
Generation & Steam
Task 4 - Multimedia
ment of Commercial/
Institutional
Sources
Task 5 - Multimedia
Pollutants assess-
ment of Industrial
Combustion Sources
Review of NAAQS for
parttculates
P-5/80-.F-I2/80
Task 1 - Multimedia
ment of Residential
Sources
Taak 2 - Multi-
media Pollutants
assessment* of 1C
Sources for
Electricity Power
Generation S Steaa
Task 3 - Multimedia
ment of other com-
bustion sources for
Electricity Power
Cener.itlon A Steam
Task 4 - Multimedia
ment of Commercial/
Institutional
Sources
Task 5 - Multimedia
ment of Industrial
Combustion Sources
Listing of
radioactive
pollutants
(how classified)
F-8/80
-------
TABLE III
Partial Draft Showing CCEA.
Support for NAAQS Development (Continued)
-—^STANDARDS I'.'IDER CONSIDERATION
"- — --^RY OAQPS
CCE/\ rECHXICAL ^~^>N_^
PROJECTS ^"""—.^^^
SYSIiMS" EN'CI V^ERI'fG
•SERVICES IDS
CC^A
(CONTRACT BEING
NECOTlAlED)
to
CO
CO
COMPARATIVE ASSESSMENT OF
COAL VS. Oil. FIRING IN
«EU. COOTRGU.ED
la US TRIAL 1. UTILITY
B01I.US
i (TRW)
ENVIRONMENTAL ASSESSMENT
OF RKIDUAL OIL
UTILIZATION
!
Review of Long Ten
HAAQS for NO,
(CAA-108)
P-t/79;F-6/79
Task 1.1 - Pollu-
tion (primary &
secondary) and
Task 3.1 -
Techniques for
quantifying
Health/Environ-
ment Effect of
Combustion
Pollutants
Task .1.2 - Total
National Emissions
of Combustion
Pollutants by
Source
Task 3.3 -
Qualitative &
Quantitative
Effects of
Criteria & Other
selected Pollutant*
Task 4.1 - Evalua-
tion at Existing,
Developmental &.
Proposed Control
Technology for
Combustion Pollu-
tants on MEG list
Task 2.1 - F.nvlron-
of Coal & Oil
Firing In
Industrial Boilers
Task 2.2 - Envlron-
of coal vs. oil
Firing tn
Utility Boilers
Development of
short tarn NAAQS
for N02 (CAA-109)
P-12/78;F-6/79
Task 1.1 - Pollu-
tion (primary i
secondary) and
Task 3.1 -
Techniques for
quantifying
Health/Environ-
ment Effect of
Combustion
Pollutants
Task 3.2 - Total
National Emissions
of Combustion
Pollutants by
Source
Task 3.3 -
Qualitative &
Quantitative
Effects of
Criteria & Other
selected Pollutant*
Task 4.1 - Evalua-
tion of Existing,
Developmental &
Proposed Control
Technology for
Combustion Pollu-
tants on MEG List
Task 2.1 - Environ-
mental assessment
of Coal i, Oil
Firing in
Industrial Boilers
Task 2.2 - Environ-
mental assessment
coal vs. oil
Firing In
Utility Boilers
Review of HAAQS for
photochemical
oxldants
F-12/78
Task 1.1 - Pollu-
tion (primary &
secondary) and
Task 3.1 -
Techniques for
quantifying
Health/Environ-
ment Etfect of
Combustion
Pollutants
Task 3.2 - Total
National Emissions
of Combustion
Pollutants by
Source
Task 3.3 -
Qualitative &
Quantitative
Effects of
Criteria & Other
selected Pollutants
Task 4.1 - Evalua-
tion of Existing,
Developmental &
Proposed Control
Technology for
Combustion Pollu-
tants on MEG lint
Task 2.1 - Envlron-
aencal assessment
of Coal & Oil
Firing in
Industrial Boilers
Task 2.2 - Envlron-
coal vs. oil
Firing in
Utility Boilers
Review of NAAQS for
CO
P-«/79i?-7/79
Task 1.1 - Pollu-
tant characteriza-
tion (primary &
secondary) and
Task 3.1 -
Techniques for
quantifying
Health/Environ-
ment Effect of
Combustion
Pollutants
Task 3.2 - Total
National Emissions
of Combustion
Pollutants by
Source
Task 3.3 -
Qualitative &
Quantitative
Effects of
Criteria & Other
selected Pollutants
Task 4.1- Evalua-
tion of Existing,
Developmental &
Proposed Control
Technology for
Combustion Pollu-
tants on MEG Mat
Task 2.1 - Environ-
mental assessment
of Coal & Oil
Firing in
Industrial Boilers
Task 2.2 - Envlron-
coal vs. oil
Firing in
Utility Boilers
Task 2 - Multimedia
Environmental Goals,
Including Existing
4 Proposed Standards,
NSPi & TLV's.
Review of NAAQS for
S0x
P-5/80-.F-12/80
Task 1.1 - Pollu-
tant characteriza-
tion (primary &
secondary) and
control levels
Task 3.1 -
Techniques for
quantifying
Health/Environ-
ment Effect of
Combustion
Pollutants
Task 3.2 - Total
National Emissions
of Combustion
Pollutants by
Source
Task 3.3 -
Qualitative &
Quantitative
Effects of
Criteria & Other
selected Pollutants
Taak 4.1 - Evalua-
tion of Existing,
Developmental &
Proposed Control
Technology for
Combustion Pollu-
tants an MEG list
Task 2.1- Environ-
mental assessment
of Coal i Oil
Firing in
Industrial Boilers
Tjaak J2.2 - Environ-
mental ausessment
coal vs. oil
Firing in
Utility Boilers
Tas,k 2 - Multimedia
Environmental Goals,
including Existing
S Proposed Standards,
NSPS & TLV's.
i.
Review of NAAQS tor
participates
P-5/80-.F- 12/80
'
Task 2.1 - Environ-
mental assessment
of Coal & Oil
Firing in
Industrial Boilers
Task 2.2 - Environ-
mental assessment
coal vs. oil
Firing in
Utility Boilers
Listing of
radioactive
pollutants
(how classified)
V-8/80
Task 2,i - Wan
for acquiring
missing data
-------
TECHNICAL REPORT DATA
(Please read Imitntctions on tfie reverse before completing}
1. REPORT NO.
EPA-600/7-79-050d
12.
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE proceedings Of the Third Stationary
Source Combustion Symposium; Volume IV. Funda-
mental Combustion Research and Environmental
Assessment •
S. REPORT DATE
February 1979
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Joshua S. Bowen, Symposium Chairman, and
Robert E. Hall, Symposium Vice-chairman
8. PERFORMING ORGANIZATION REPORT NO.
I. PERFORMING ORGANIZATION NAME AND ADDRESS
See Block 12.
10. PROGRAM ELEMENT NO.
EHE624
11. CONTRACT/GRANT NO.
NA (Inhouse)
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 277U
13. TYPE OF REPORT AND PI
Proceedings; 3/79
PERIOD COVERED
14. SPONSORING AGENCY CODE
EPA/600/13
is.SUPPLEMENTARY NOTES TERL_RTppro|ectofficer jg Robert E. Hall. MD-65, 919/541-
2477. EPA-600/7-77-073a thriS -(T73e and EPA-600/2-76-152a thru -152c are pro-
ceedings of earlier symposiums on the same theme.
IB. ABSTRACT The pjQcgedjngg document the approximately 50 presentations made during
the symposium, March 5-8, 1979, in San Francisco. Sponsored by the Combustion
Research Branch of EPA's Industrial Environmental Research Laboratory-RTF,
the symposium dealt with subjects relating both to developing improved combustion
technology for the reduction of air pollutant emissions from stationary sources,
and to improving equipment efficiency. The symposium was in seven parts, and
the proceedings are in five volumes: I. Utility, Industrial, Commercial, and Resi-
dential Systems; n. Advanced Processes and Special Topics; m. Stationary Engine
and Industrial Process Combustion Systems; IV. Fundamental Combustion Research
and Environmental Assessment; and V. Addendum. The symposium provided contra-
ctor, industrial, and government representatives with the latest information on EPA
inhouse and contract combustion research projects relating to pollution control,
with emphasis on reducing NOx while controlling other emissions and improving
efficiency.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
Air Pollution
Combustion
Field Tests
Assessments
Combustion Control
Fossil Fuels
Boilers
Gas Turbines
Nitrogen Oxides
Efficiency
Utilities
Industrial Pro-
cesses
Hydrocarbons
Air Pollution Control
Stationary Sources
Environmental Assess-
ment
Combustion Modification
Trace Species
Fuel Nitrogen
T3B"
21B
14B
21D
13A
T3TT
07B
13H
07C
8. DISTRIBUTION STATEMENT
Unlimited
1». SECURITY CLASS (This Report}
Unclassified
21. NO. OF PAGES
20. SECURITY CLASS (Thispage!
Unclassified
22. PRICE
EPA Form 2220-1 (••73)
234
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