United States
Environmental Protection
Agency
Air and Energy Engineering
Research Laboratory
Research Triangle Park NC 27711
Research and Development
EPA/600/S8-86/023 Nov. 1986
&EPA Project Summary
o
Identification, Assessment
and Control of Fugitive
Particulate Emissions
Chatten Cowherd, Jr. and John S. Kinsey
To assist national, state, and local
control agency personnel and industry
personnel in evaluating fugitive emis-
sion control plans and in developing
cost-effective control strategies, the
U.S. Environmental Protection Agency
has funded the preparation of a techni-
cal manual on the identification,
assessment, and control of fugitive par-
ticulate emissions. This report summa-
rizes the organizational structure and
content of the manual. The organiza-
tional structure follows the steps to be
undertaken in developing a cost-
effective control strategy for fugitive
particulate emissions. The procedural
steps are the same whether the sources
of interest are within a specific indus-
trial facility or distributed over an air
quality control jurisdiction.
The manual summarizes the quality
and extent of published performance
data for control systems applicable to
open dust sources and process sources.
The scheme developed to rate perform-
ance data reflects the extent to which a
control efficiency value is based on
mass emission measurement and re-
ported in enough detail for adequate
validation. In addition to presenting a
cost analysis methodology, the manual
identifies primary cost elements and
sources of cost data and presents a fully
worked industrial example of cost-
effective control strategy development.
This Project Summary was devel-
oped by EPA's Air and Energy Engineer-
ing Research Laboratory, Research Tri-
angle Park, NC, to announce key
findings of the research project that is
fully documented in a separate report
of the same title (see Project Report or-
dering information at back).
Introduction
Fugitive particles are emitted by a
wide variety of sources both in the in-
dustrial and nonindustrial sectors. Fugi-
tive emissions are those air pollutants
that enter the atmosphere without first
passing through a stack or duct de-
signed to direct or control their flow.
Fugitive particulate emission sources
may be separated into two broad cate-
gories: process sources and open dust
sources. Process sources of fugitive
emissions are those associated with in-
dustrial operations that alter the chemi-
cal or physical characteristics of a feed
material; e.g., emissions from charging
and tapping of metallurgical furnaces
and those from crushing of mineral ag-
gregate. Such emissions normally
occur within buildings and, unless cap-
tured, are discharged to the atmosphere
through forced or natural draft ventila-
tion systems. Open dust sources entail
the entrainment of solid particles into
the atmosphere by the forces of wind or
machinery acting on exposed materials.
Open dust sources include industrial
sources associated with the open trans-
port, storage, and transfer of raw, inter-
mediate, and waste materials, and non-
industrial sources such as unpaved and
paved public roads and construction ac-
tivities.
To assist national, state, and local
control agency personnel in evaluating
fugitive emission control plans and to
assist industry personnel in developing
cost-effective control strategies, the
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U.S. EPA has funded the preparation of
a technical manual on the identification,
assessment, and control of fugitive par-
ticulate emissions. The manual de-
scribes the procedures for developing a
cost-effective strategy for the control of
fugitive particulate emissions within
any specific plant or area setting. Also, it
provides sources of data or in some
cases actual data needed to implement
the procedures.
Within the manual, cost-effectiveness
is defined as the annualized cost of con-
trol divided by the reduction in total an-
nual particulate emissions ($/Mg), as a
result of the fugitive emission control
system being used. Control costs in-
clude the capital, operating, and
maintenance costs associated with the
system over its useful life.
Scope of Document
The manual describes the recom-
mended steps in developing a cost-
effective control strategy for specific
sources of fugitive particulate emis-
sions. Whether the sources of interest
are contained within a specific indus-
trial facility or distributed over an air
quality control jurisdiction, the general
procedure for control strategy develop-
ment is the same:
1. Source identification.
2. Preparation of an emissions inven-
tory.
3. Identification of control alterna-
tives.
4. Estimation of control system per-
formance.
5. Estimation of control costs.
6. Selection of cost-effective con-
trols.
Figure 1 summarizes the procedure. It is
assumed that the need for a reduction in
emissions has been determined as re-
quired to achieve a desired net improve-
ment in air quality or to provide an off-
set for an increase in emissions from an
expanding source operation.
Unless otherwise indicated, use of the
term particulate emissions in the man-
ual refers to the particle size fraction col-
lected by the standard high-volume
sampler, which is the reference device
for the existing National Ambient Air
Quality Standards for particulate mat-
ter. Although the standard high-volume
sampler does not have a sharp particle
size cut-point for capture of airborne
particulate matter, an effective cut-point
of 30 u-mA (aerodynamic diameter) is
frequently assigned. This particle size
fraction is normally referred to as total
suspended particulate matter (TSP).
estimate Net
Air Quality
Improvement
Establish Need for
Control of Fugitive
Particulate Emissions
I
Identify and
Classify Sources
Estimate Existing
Emissions from
Each Source
I
Rank Order
Most Significant
Sources
I
For Each Source
Identify Applicable
Control Options
Determine Required
Emissions Reductions
I
Select Candidate
Controls for
Evaluation
I
Estimate Cost of
Each Control
Finalize Control
Strategy
I
Select Most
Cost-Effective
Control
Figure 1.
Flow diagram for the identification, assessment, and control of fugitive particul
emissions.
Other particle size fractions cited in the
manual include:
TP Total airborne particulate mat-
ter.
IP Inhalable particulate matter
consisting of particles equal to
or smaller than 15 fimA.
PM10 Particulate matter consisting of
particles equal to or smaller
than 10 jimA.
FP Fine particulate matter consist-
ing of particles equal to or
smaller than 2.5 ^mA.
The organization of the manual (i.e.,
chapter designations) reflects an em-
phasis on control technology in relati
to the other technical areas associai
with control strategy developme
Also, greater emphasis is placed
open dust sources than on proci
sources. This, in fact, is consistent w
the larger body of available data on
performance of open dust source c
trols (focusing on controls applicabli
unpaved roads). Finally, although fi
tive particulate emissions can be
duced by reducing the extent of
source, the document focuses on
use of add-on controls which do nol
feet the size or throughput of the sou
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While a variety of control techniques
applicable to sources of fugitive panicu-
late emissions are discussed in the doc-
ument, control efficiency values are
specified only for control options which
have been tested for effectiveness.
However, the reader is referred to other
review documents which present esti-
mated values of control efficiency for
control options which have no pub-
lished performance data. The scheme
used in the technical manual to rate
control performance data is based on
the quality of the supporting test data
and the adequacy of documentation in
the test reports.
The chapter contents of the manual
are:
• Chapter 2 (Source Identification)
defines the terms used to identify
sources of fugitive paniculate emis-
sions, describes generic source cat-
egories, and classifies specific
sources by generic category within
each major industry in a matrix for-
mat.
• Chapter 3 (Preparation of an Emis-
sions Inventory) reviews the stand-
ard procedures used to develop an
emissions inventory and to deter-
mine the desired reduction in par-
ticulate emissions from fugitive
sources.
• Chapter 4 (Identification of Control
Alternatives) identifies control al-
ternatives by generic category and
presents a matrix of feasible con-
trol alternatives for specific sources
within each major industry.
• Chapter 5 (Estimation of Control
System Performance—Open
Sources) documents and rates pub-
lished performance data on open
source controls, identifies the
parameters which affect control
performance, and compiles per-
formance data for control alterna-
tives applicable to each generic
source category.
• Chapter 6 (Estimation of Control
System Performance—Process
Sources) documents and rates pub-
lished performance data on proc-
ess source controls, identifies the
parameters which affect control
performance, and compiles per-
formance data for control alterna-
tives applicable to each generic
source category.
• Chapter 7 (Estimation of Control
Costs and Cost-Effectiveness) de-
scribes estimation procedures for
capital, operating, and mainte-
nance costs, and outlines the
methodology for calculating cost-
effectiveness of continuously and
periodically applied controls.
• Chapter 8 (Fugitive Emissions Con-
trol Strategy Development) is a hy-
pothetical case study, presenting a
fully worked industrial example il-
lustrating the procedural steps for
control strategy development, in-
cluding the capital, operating, and
maintenance costs of representa-
tive controls.
• Appendix A (Estimation of Air Qual-
ity Impact/Improvement) describes
the mathematical modeling tech-
niques for assessing the air quality
impact of specific sources and for
predicting the improvement in air
quality resulting from the imple-
mentation of specific controls.
• Appendix B is a glossary of terms
used in the manual.
Identification of Control
Alternatives
Chapter 4 of the manual identifies
control alternatives for open dust
sources and for process sources of fugi-
tive paniculate emissions. More than
one option for reduction of the uncon-
trolled emission rate can be considered.
To begin with, the uncontrolled emis-
sion rate is the product of the source
extent and uncontrolled emission fac-
tor. A reduction in either variable pro-
duces a proportional reduction in the
uncontrolled emission rate.
Although the reduction of source ex-
tent results in a highly predictable re-
duction in the uncontrolled emission
rate, such an approach in effect usually
requires a change in the process opera-
tion. Frequently, reduction in the extent
of one source may necessitate an in-
crease in the extent of another, as in the
shifting of vehicle traffic from an un-
paved road to a paved road. The option
of reducing source extent is beyond the
scope of this manual and will not be
discussed further.
The reduction in the uncontrolled
emission factor may be achieved by
process modifications (in the case of
process sources) or by adjusted work
practices (in the case of open sources).
The key to the possible reduction of the
uncontrolled emission factor is the
knowledge of how the factor depends
on the source conditions that might be
subject to alteration. For open dust
sources, this information is embodied
in the predictive emission factor equa-
tions for fugitive dust sources as pre-
sented in Section 11.2 of "Compilation
of Air Pollutant Emission Factors" (EPA
report AP-42, Volume I, GPO 055-000-
00251-7, September 1985).
Besides the reduction of source ex-
tent and the incorporation of process
modifications, two basic techniques can
be utilized to control fugitive paniculate
emissions: prevention of the creation
and/or release of paniculate matter into
the atmosphere, and capture and re-
moval of the airborne particles. Control
of open dust sources by work practices
fits under the category of preventive
measures.
Open Dust Sources
The alternative approaches available
for the control of open dust sources in-
clude:
1. Stabilization of Unpaved Travel
Surfaces
* Wet suppression
• Chemical stabilization
• Physical stabilization
• Paving
2. Improvement of Paved Travel Sur-
faces
• Surface cleaning
* Resurfacing
• Reduction of track-on
3. Stabilization of Piles/Exposed
Areas
• Wet suppression
• Chemical stabilization
• Physical stabilization
4. Enclosure of Piles/Exposed Areas
or Materials Handling
• Passive enclosures (including
wind fences)
• Active enclosures
5. Wet Suppression for Materials
Handling
6. Plume Aftertreatment for Materials
Handling
• Fine water sprays
• Charged fog
The first three of these categories, pas-
sive enclosures, and wet suppression
are preventive measures; whereas, ac-
tive enclosures and plume aftertreat-
ment are capture/removal methods.
Published performance data on open
dust source controls are presented in
Chapter 5 of the manual.
Most of the preventive measures in-
volve periodic rather than continuous
control application. Familiar examples
are the watering of unpaved travel sur-
faces and the cleaning of paved travel
surfaces. The resultant control effi-
ciency follows a cyclic pattern, decaying
in time from the highest value immedi-
ately after application. Because of the
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finite durability of these control tech-
niques, ranging from hours to months,
it is essential to relate an efficiency
value to a frequency of application. For
measure of lengthy durability such as
paving, the application program re-
quired to sustain control effectiveness
should be indicated. One likely pitfall is
the use of field data collected soon after
control measure application to repre-
sent the average control efficiency over
the lifetime of the measure.
For a periodically applied control
measure, the most representative value
of control efficiency is the time average,
given by:
cm = 4 c(t)dt
(1)
where C(T) = average control efficiency
during a period of T days
between applications
(percent)
c(t) = instantaneous control ef-
ficiency at t days after ap-
plication (percent), where
tST.
It must be emphasized that the rate of
control efficiency decay is heavily de-
pendent upon the source and control
variables discussed below.
Process Sources
The alternative approaches available
for the control of process fugitive emis-
sions include:
1. Wet Suppression
• Water sprays (with and without
chemical additives)
• Foams
2. Enclosures
• Passive enclosures (without
evacuation)
• Active enclosures (with evacua-
tion to a dust collector)
3. Hooding Systems
• Receiving hoods
- Canopy hoods
- Close capture hoods
- Hoods for mechanically di-
rected plumes
• Capture hoods
- Side draft hoods
- Push/pull hooding systems
- High-velocity low-volume
hoods
- Close capture hoods
4. Plume After-treatment
• Fine water sprays
• Electrostatic foggers
Wet suppression and passive enclo-
sures are preventive measures;
whereas, hooding systems and plume
aftertreatment are capture/removal
methods. All of these controls are de-
signed to be continuously applied. Per-
formance data on process controls are
presented in Chapter 6 of the manual.
Estimation of Control Costs
and Cost Effectiveness
Development and evaluation of par-
ticulate fugitive emissions control
strategies require analyses of the rela-
tive costs of alternative control mea-
sures. Cost analyses are used by control
agency personnel to develop overall
strategies for an air pollution control
district or to evaluate plant specific con-
trol strategies. Industry personnel per-
form cost analyses to evaluate control
alternatives for a specific source or to
develop a plant-wide emissions control
strategy. Although the specifics of these
analyses may vary, depending on the
objective of the analysis and the avail-
ability of cost data, the general format is
similar.
The primary goal of any cost analysis
is to provide a consistent comparison of
the real costs of alternative control mea-
sures. The aim of this portion of the
manual is to provide the reader with a
methodology that will allow such a
comparison. It describes the overall
structure of a cost analysis and provides
the resources for conducting the analy-
ses. Because cost data are continuously
changing, specific cost data are not pro-
vided. However, sources of cost infor-
mation and mechanisms for cost updat-
ing are provided.
The approach outlined in Chapter 7
of the manual focuses on cost-
effectiveness as the primary compari-
son tool. Cost-effectiveness is the ratio
of the annualized cost of the emissions
control to the amount of emissions re-
duction achieved. Mathematically, cost-
effectiveness is defined by:
-
AR
(2)
where C* = cost effectiveness ($/mass
of emissions reduction)
Ca = annualized cost of the con-
trol measure ($/year)
AR = reduction (mass/year) in
annual emissions
The annualized cost includes capital,
operating, and maintenance costs aver-
aged over the useful life of the associ-
ated control equipment.
Cost-effectiveness for comparison of
control measures or control strategies
can be calculated in four steps: (1) alter-
native control/cost scenarios are se-
lected, (2) capital costs of each scenario
are calculated, (3) annualized costs foi
each alternative are developed, anc
(4) the cost-effectiveness is calculated
taking into consideration the level o
emissions reduction.
The discussion of control costs anc
cost effectiveness in Chapter 7 is di
vided into three sections: (1) a descrip
tion of the general cost analysi:
methodology, including the variou:
types of costs that should be considerei
and methods for calculating thos
costs; (2) identification of the primar
cost elements associated with eac
fugitive emissions control system ider
tified in Chapter 4; and (3) identificatio
of the sources of cost data, includin
methods for updating cost data to cor
stant dollars. Chapter 8 of the manu;
presents a fully worked industrial exan
pie illustrating the procedural steps f<
cost-effective control strategy develoi
ment.
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C. Cowherd, Jr., andJ. Kinsey are with Midwest Research Institute, Kansas City,
MO 64110.
Dale L. Harmon is the EPA Project Officer (see below).
The complete report, entitled "Identification, Assessment, and Control of Fugitive
Paniculate Emissions," (Order No. PB 86-230 083/A S; Cost: $16.95, subject to
change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Air and Energy Engineering Research Laboratory
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
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United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Official Business
Penalty for Private Use $300
EPA/600/S8-86/023
0000329 PS
PROTECTION AGENCY
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