MIDWEST RESEARCH INSTITUTE
EPORT
CONTROL TECHNOLOGY FOR SOURCES OF PM10
DRAFT REPORT
EPA Contract No. 68-02-3891, Work Assignment 4
MRI Project No. 8281-L(4)
September 1985
For
U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Control Programs Development Division
Research Triangle Park, North Carolina 27711
At.t.n- Mr
Woodard
KANSAS CITY, MISSOURI 64110-816 753-7600
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MRI WASHINGTON, D.C. 20006-Suite 250, 1750 K Street, N.W. • 202 293-3800
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CONTROL TECHNOLOGY FOR SOURCES OF PMi0
By
John S. Kinsey
Steven Schllesser
Phillip J. Englehart
DRAFT REPORT
EPA Contract No. 68-02-3891, Work Assignment 4
MRI Project No. 8281-L(4)
September 1S85
For
U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Control Programs Development Division
Research Triangle Park, North Carolina 27711
Attn: Mr. Kenneth R. Woodard
MIDWEST RESEARCH INSTITUTE 425 VOLKER BOULEVARD, KANSAS CITY, MISSOURI 64110 • 816 753-7600
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PREFACE
This report was prepared by Midwest Research Institute (MRI) for the
U.S. Environmental Protection Agency's Control Programs Development Division
as part of Work Assignment 4 of Contract No. 68-02-3891. Mr. Kenneth Woodard
was the EPA project officer. The work was performed in MRI's Air Quality
Assessment Section (Dr. Chatten Cowherd, Head). The report was prepared
by Mr. John Kinsey (Principal Investigator), Mr. Steve Schliesser, and
Mr. Phillip Englehart.
Approved for:
MIDWEST RESEARCH INSTITUTE
M. P. Schrag, Directol
Environmental Systems Department
September 1985
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CONTENTS
Preface iii
Figures vi
Tables vii
1.0 Introduction 1-1
1.1 Definitions 1-2
1.2 Reference documents 1-8
1.3 Organization of handbook 1-8
2.0 Quantification of Uncontrolled Emissions 2-1
2.1 Ducted source emission factors 2-2
2.2 Process fugitive emission factors 2-3
2.3 Open source emission factors 2-4
3.0 Control Alternatives for PM10 3-1
3.1 Control alternatives for ducted sources 3-2
3.2 Control alternatives for fugitive emissions. . . 3-23
4.0 Estimation of Control Costs and Effectiveness 4-1
4.1 General cost methodology 4-2
4.2 Cost elements and sources of data 4-9
' 4.3 Generalized cost estimate procedures 4-11
4.4 Example cost estimate calculations 4-12
5.0 Methods of Compliance Determination 5-1
5.1 Source testing methods for PMio 5-1
5.2 Methods for determining visible emissions. ... 5-8
5.3 Other methods for determining compliance .... 5-17
Appendices
A. Procedures for sampling surface/bulk materials A-l
B. Procedures for laboratory analysis of surface/bulk
samples B-l
C. Procedures for quantification of traffic characteristics. . C-l
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FIGURES
Number Page
2-1 Mean number of days with 0.01 in. or more of precipi-
tation in United States 2-8
3-1 General types of cyclones 3-6
3-2 Basic processes in electrostatic precipitation 3-8
3-3 Initial mechanisms of fabric filtration 3-14
3-4 Diagram of a portable wind screen 3-28
3-5 Diagrams of typical street cleaners 3-33
3-6 General types of capture devices (hoods) 3-36
3-7 Converter air curtain control system 3-39
3-8 Electrostatic foggers 3-41
4-1 Cost of venturi scrubbers, unlined throat with carbon
steel construction 4-69
4-2 Capital and annualized costs of venturi scrubbers with
carbon steel construction 4-70
4-3 Capital and annualized costs of venturi scrubbers with
stainless steel construction 4-71
4-4 Cost of electrostatic precipitators with carbon steel
construction 4-72
4-5 Capital and annualized costs of electrostatic with
carbon steel construction 4-73
4-6 Cost of fabric filters with carbon steel construction. . . 4-74
4-7 Capital and annualized costs of fabric filters with
stainless steel construction 4-75
4-8 Capital and annualized costs of fabric filters with
carbon steel construction 4-76
4-9 Capital and annualized costs of fans and 30.5 m (100 ft)
length of duct 4-77
4-10 Capital and annualized costs of fan driver for various
head pressures 4-78
5-1 PMio particulate sampling train for noncondensible
participate (Modified EPA Method 5 train) 5-3
5-2 PMio particulate sampling train for condensible and
noncondensible particulate (Modified EPA Method 5
train) 5-4
5-3 Schematic of the Emission Gas Recycle (EGR) sampling
train 5-6
5-4 Recommended sampling points for circular and square or
rectangular ducts 5-7
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TABLES
Number Page
1-1 Categories of Process Fugitive Sources 1-3
1-2 Generic Categories of Open Dust Sources 1-6
1-3 Open Dust Sources Associated with Construction and
Demolition 1-7
1-4 List of Standard Reference Documents 1-9
2-1 Range of Source Conditions for Equation 2-4 2-9
2-2 Range of Source Conditions for Equation 2-5 2-10
2-3 Paved Urban Roadway Classification 2-12
2-4 Summary of Silt Loading (sL) Values for Paved Urban
Roadways 2-12
2-5 Recommended PM10 Emission Factors for Specific Roadway
Categories 2-13
2-6 Ranges of Source Conditions for Equations 2-7 and 2-8. . . 2-16
2-7 Typical Silt Content Values of Surface Materials on
Industrial and Rural Unpaved Roads 2-19
2-8 Typical Silt Content and Loading Values for Paved Roads
at Industrial Facilities 2-20
2-9 Typical Silt and Moisture Content Values of Materials at
Various Industries 2-21
2-10 Typical Correction Parameters Determined for Unpaved
Roads 2-23
2-11 Typical Correction Parameters Determined for Industrial
Paved Roads 2-25
2-12 Typical Correction Parameters Determined for Aggregate
Handling and Storage Piles 2-26
3-1 Standard Reference Documents for Industrial Gas Cleaning
Equipment 3-3
3-2 Major Types of Mechanical Dust Collectors 3-3
3-3 Major Types of Wet Scrubbers 3-16
3-4 Typical Scrubber Pressure Drop 3-18
3-5 Typical PM10 Control Efficiencies for Mechanical Dust
Collectors 3-20
3-6 Typical PMio Control Efficiencies for Electrostatic
Precipitators and Fabric Filters 3-21
3-7 Typical PM10 Control Efficiencies for Wet Scrubbers. . . . 3-22
3-8 Additional Reference Documents for Fugitive Emission
Controls 3-25
3-9 Process Fugitive Particulate Emission Sources and
Feasible Control Technology 3-42
3-10 Feasible Control Measures for Open Dust Sources 3-45
vn
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TABLES (continued)
Number Page
3-11 Summary of Available PM10 Control Efficiency Data for
Water Sprays and Foam Suppression (Process Sources). . . 3-47
3-12 Summary of PM10 Control Efficiency Data for Capture/
Collection Systems (Process Sources) 3-48
3-13 Summary of Available Control PM10 Efficiency Data for
Plume Aftertreatment Systems (Process Sources) 3-49
3-14 Open Dust Source Control Technique Identification 3-52
3-15 Instantaneous PMxo Control Efficiency for Unpaved Road
Control Techniques as a Function of Vehicle Passes . . . 3-54
3-16 Field Data on Unpaved Road Watering Control Efficiency . . 3-55
3-17 Summary of Available PM1() Control Efficiency Data for
Water Sprays (Open Dust Sources) 3-56
3-18 Summary of Available PMjo Control Efficiency Data for
Foam Suppression Systems (Open Dust Sources) 3-57
3-19 Summary of Available PM10 Control Efficiency Data for
Plume Aftertreatment Systems (Open Dust Sources) .... 3-59
4-1 Typical Capital Cost Elements 4-16
4-2 Typical Values for Indirect Capital Costs 4-16
4-3 Typical Annualized Cost Elements 4-17
4-4 Control Alternatives for Wet Scrubbers 4-18
4-5 Control Alternatives for Electrostatic Precipitators . . . 4-20
4-6 Control Alternatives for Fabric Filters 4-22
4-7 Control Alternatives for Wet Suppression of Process
Fugitives 4-24
4-8 Control Alternatives for Capture/Collection Systems. . . . 4-25
4-9 Control Alternatives for Plume Aftertreatment Systems. . . 4-27
4-10 Control Alternatives for Stabilization of Unpaved
Travel Surfaces 4-28
4-11 Control Alternatives for Improvement of Paved Travel
Surfaces 4-29
4-12 Control Alternatives for Wet Suppression of Unpaved
Surfaces 4-30
4-13 Control Alternatives for Paving 4-31
4-14 Capital Equipment and O&M Expenditure Items for Wet
Scrubbers 4-32
4-15 Capital Equipment and O&M Expenditure Items for
Electrostatic Precipitators 4-33
4-16 Capital Equipment and O&M Expenditure Items for
Fabric Filters 4-34
4-17 Capital Equipment and O&M Expenditure Items for Wet
Suppression of Process Fugitive Emissions 4-35
4-18 Capital Equipment and O&M Expenditure Items for Capture/
Collection Systems 4-36
4-19 Capital and O&M Expenditures for Plume Aftertreatment
Systems 4-37
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TABLES (continued)
Number . Page
4-20 Capital Equipment and O&M Expenditure Items for Chemical
Stabilization of Unpaved Travel Surfaces 4-38
4-21 Capital Equipment and O&M Expenditure Items for
Improvement of Paved Travel Surfaces 4-39
4-22 Capital Equipment and O&M Expenditure Items for Paving . . 4-40
4-23 Typical Costs for Wet Suppression of Process Fugitive
Sources 4-41
4-24 Typical Costs for Wet Suppression of Open Sources 4-42
4-25 Selected Cost Estimates for Stabilization of Open Dust
Sources 4-43
4-26 Cost Estimates for Improvement of Paved Travel Surfaces. . 4-44
4-27 Example Calculation Case: Control Cost Alternatives for
Wet Scrubber on Ducted Sources 4-45
4-28 Example Calculation Case: Capital Equipment and O&M
Expenditure Items for a Wet Scrubber on a Typical
Ducted Source 4-47
4-29 Example Calculation Case: Capital Costs for a Wet
Scrubber on a Typical Ducted Source 4-48
4-30 Example Calculation Case: Annualized Costs and Cost-
Effectiveness for a Wet Scrubber on a Typical Ducted
Source 4-51
4-31 Example Calculation Case: Control Cost Alternatives for
Wet Suppression of Process Fugitive Emissions 4-53
4-32 Example Calculation Case: Capital Equipment and O&M
Expenditure Items for Wet Suppression of Process
Fugitive Emissions 4-54
4-33 Example Calculation Case: Cost Estimation for Process
Fugitive Control 4-55
4-34 Example Calculation Case: Cost and Cost Effectiveness
Estimate for Typical Open Source Control 4-57
4-35 Alternative Control Program Design for Coherex® Applied
to Travel Surfaces 4-63
4-36 Alternative Control Program Design for Petro Tac Applied
to Unpaved Travel Surfaces 4-64
4-37 Identification and Cost Estimation of Coherex® Control
Alternatives 4-65
4-38 Identification and Cost Estimation of Petro Tac Control
Alternatives 4-67
5-1 Summary of EPA Method 9 Requirements (M9) 5-9
5-2 Summary of Modified EPA Method 9 for Basic Oxygen
Process Furnaces (MM9) 5-10
5-3 Summary of EPA Method 22 Requirements (M22) 5-11
5-4 Summary of TVEE Method 1 Requirements (Ml) 5-14
5-5 Recommended Operating Parameters for Monitoring of ESP
Performance 5-20
IX
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TABLES (concluded)
Number
5-6 Recommended Operating Parameters for Monitoring of Fabric
Filter Performance 5-21
5-7 Recommended Operating Parameters for Monitoring of Wet
Scrubber Performance 5-23
5-8 Typical Form for Recording Chemical Dust Suppressant
Control Parameters 5-25
5-9 Typical Form for Recording Delivery of Chemical Dust
Suppressants 5-26
5-10 Typical Form for Recording Watering Program Control
Parameters 5-27
5-11 Typical Form for Recording Paved Road/Parking Area
Control Parameters 5-29
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SECTION 1.0
INTRODUCTION
The U.S. Environmental Protection Agency (EPA) has proposed national
ambient air quality standards (NAAQS) for particulate matter based on par-
ticles of a size equal to or smaller than 10 microns (urn) in aerodynamic
diameter (PM-wO for the primary standard, and total suspended particulate
(TSP) for the secondary standard. TSP is defined as particulate matter
which is of a size approximately equal to or smaller than 30 microns (urn)
in aerodynamic diameter. Revision of the standards will make it necessary
that State Implementation Plans (SIPs) be reviewed to determine changes
that may be required to attain and maintain the new standards. Included in
the SIP review process will be an analysis of the existing control strategy
to determine whether additional control technology will be required for
existing sources of PMio to attain and maintain the new NAAQS.
In order to develop appropriate control strategies for sources of PMio
a step-wise procedure must be followed. This procedure includes: (1) the
determination of uncontrolled PMio emission rates; (2) the identification
of available control options; (3) the determination of the emissions reduc-
tion achieved by various control options; and (4) the estimation of control
costs and cost-effectiveness for each option. This document will provide
guidance on each step in the above procedure. It will also present various
approaches for determining compliance with applicable PMio emission stan-
dards (when promulgated), based on either a determination of on-site per-
formance (e.g., source tests, opacity) or other procedures such as record-
keeping. First, appropriate definitions and reference documents will be
presented as an introduction to the main discussion provided in the follow-
ing sections.
1-1
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1.1 DEFINITIONS
Ducted emission sources are those sources of particulate matter which
vent emissions to the atmosphere through a stack, vent, or pipe designed to
direct or control their flow. Point sources are usually controlled by
means of one or more types of traditional industrial gas cleaning equipment
such as electrostatic precipitators, baghouses, and wet scrubbers.
Fugitive emissions refer to those pollutants that: (1) enter the atmo-
sphere without first passing through a stack or duct designed to direct or
control their flow; or (2) leak from ducting systems. Sources of fugitive
particulate emissions may be separated into two broad categories: process
sources and open dust sources.
Process sources of fugitive emissions are those associated with indus-
trial operations that alter the chemical or physical characteristics of a
feed material. Examples are emissions from charging and tapping of metal-
lurgical furnaces and emissions from crushing of mineral aggregates. Such
emissions normally occur within buildings and, unless captured, are dis-
charged to the atmosphere through forced or natural draft ventilation sys-
tems. However, a process source can also be located in the open atmosphere
(e.g., scrap metal cutting). The most significant process sources of fugi-
tive particulate emissions are listed by industry in Table 1-1.
Open dust sources are those which entail generation of fugitive emis-
sions by the forces of wind or machinery acting on exposed materials. Open
dust sources include industrial operations associated with the open trans-
port, storage, and transfer of raw, intermediate, and waste aggregate mate-
rials and nonindustrial sources such as unpaved roads and parking lots,
eupwJ wm
paved streets and highways, heavy construction activities, and agricultural
tilling. Generic categories of open dust sources are listed in Table 1-2.
1-2
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TABLE 1-1. CATEGORIES OF PROCESS FUGITIVE SOURCES
Industry
Process source
Iron and Steel Plants
Ferrous Foundries
Primary Aluminum Production
Primary Copper Smelters
Primary Copper Smelters
Coal Crushing/Screening
Coke Ovens
Coke Oven Pushing
Sinter Machine Windbox
Sinter Machine Discharge
Sinter Cooler
Blast Furnace Charging
Blast Furnace Tapping
Slag Crushing/Screening
Molten Iron Transfer
BOF Charging/Tapping/Leaks
Open Hearth Charging/Tapping/Leaks
EAF Charging/Tapping/Leaks
Ingot Pouring
Continuous Casting
Scarfing
Furnace Charging/Tapping
Ductile Iron Inoculation (w/wo tundish
cover)
Pouring of Molten Metal
Casting Shakeout
Cooling/Cleaning/Finishing of Castings
Core Sand and Binder Mixing
Grinding/Screening/Mixing/
Paste Production
Anode Baking
Electrolytic Reduction Cell
Refining and Casting
Roaster Charging
Roaster Leaks
Furnace Charging/Tapping/
Leaks
Slag Tapping/Handling
Converter Charging/Leaks
Blister Copper Tapping/Transfer
Copper Tapping/Casting
(continued)
1-3
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TABLE 1-1. (continued)
Industry
Process source
Primary Lead Smelters
Primary Zinc Production
Secondary Aluminum Smelters
Secondary Lead Smelters
Secondary Zinc Production
Raw Material Mixing/Pelletizing
Sinter Machine Leaks
Sinter Return Handling
Sinter Machine Discharge/Screens
Sinter Crushing
Blast Furnace Charging/Tapping
Lead and Slag Pouring
Slag Cooling
Slag Granulator
Zinc Fuming Furnace Vents
Dross Kettle
Silver Retort Building
Lead Casting
Sinter Machine Windbox Discharge
Sinter Machine Discharge/Screens
Coke-Sinter Mixer
Furnace Tapping
Zinc Casting
Sweating Furnace
Smelting Furnace Charging/Tapping
Fluxing
Dross Handling and Cooling
Scrap Burning
Sweating Furnace Charging/Tapping
Reverb Furnace Charging/Tapping
Blast Furnace Charging/Tapping
Pot Furnace Charging/Tapping
Tapping of Holding Pot
Casting
Sweating Furnace Charging/Tapping
Hot Metal Transfer
Melting Furnace Charging/Tapping
Distillation Retort Charging/Tapping
Distillation Furnace Charging/Tapping
Casting
(continued)
1-4
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TABLE 1-1. (concluded)
Industry
Process source
Secondary Copper, Brass/
Bronze Production
Ferroalloy Production
Cement Manufacturing
Lime Manufacturing
Rock Products
Asphalt Concrete Plants
Coal-Fired Power Plants
Grain Storage and Processing
Wood Products Industry
Mining
Sweating Furnace Charging/Tapping
Dryer Charging/Tapping
Melting Furnace Charging
Casting
Raw Materials Crushing/
Screening
Furnace Charging
Furnace Tapping
Casting
Limestone/Gypsum Crushing and
Screening
Coal Grinding
Limestone Crushing/Screening
Lime Screening/Conveying
Blasting
Primary Crushing/Screening
Secondary Crushing/Screening
Tertiary Crushing Screening
Aggregate Crushing/Screening
Pugmi11/Dryer Drum
Coal Pulverizing/Screening
Grain Cleaning
Grain Drying
Log Debarking/Sawing
Veneer Drying
Plywood Cutting
Plywood Sanding
Blasting
Crushing/Screening
1-5
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TABLE 1-2. GENERIC CATEGORIES OF OPEN DUST SOURCES
1. Unpaved Travel Surfaces
Roads
Parking lots and staging areas
Storage piles
2. Paved Travel Surfaces
Streets and highways
Parking lots and staging areas
3. Exposed Areas (wind erosion)
Storage piles
Bare (unvegetated) ground areas
4. Materials Handling
Batch drop (dumping)
Continuous drop (conveyor transfer, stacking)
Pushing (dozing, grading, scraping)
Tilling
The partially enclosed storage and transfer of materials to or from a
process operation do not fit well into either of the two categories of
fugitive particulate emissions defined above. Examples are partially en-
closed conveyor transfer stations and front-end loaders operating within
buildings. Nonetheless, partially enclosed materials handling operations
should be classified as open sources.
The various open dust sources listed in Table 1-2 can be found either
in an industrial facility or in the public sector. The mechanisms of dust
formation and thus the type of controls which can be applied in either
case are essentially the same. However, both the suitability and cost-
effectiveness associated with a specific control measure can change sig-
nificantly when applied in an industrial setting as compared to the same
control used for public sector sources. Therefore, the control strategies
1-6
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developed by public agencies often differ from those employed by industrial
concerns.
A number of public sector sources are perceived as single sources when
in actuality they are a series of different dust generating operations con-
fined to the same locality. Examples of this type of source include con-
struction and demolition activities, both of which involve dust generation
by various materials handling operations as well as vehicular traffic.
Table 1-3 lists the specific sources associated with construction and demo-
lition activities using the same general notation indicated in Tables 1-1
and 1-2 above.
TABLE 1-3. OPEN DUST SOURCES ASSOCIATED WITH
CONSTRUCTION AND DEMOLITION
Construction Sites
• Vehicular traffic on unpaved surfaces
• Storage piles
• Mud/dirt carryout onto paved travel surfaces
• Exposed areas
• Batch drop operations
• Pushing (earth moving)
Demolition Sites
• Vehicular traffic on unpaved surfaces
• Storage piles
• Mud/dirt carryout onto paved travel surfaces
• Exposed areas
• Batch drop operations
• Pushing (dozer operation)
• Blasting
One final public sector source worthy of note is agricultural tilling.
Tilling involves those operations associated with soil preparation, main-
tenance, and crop harvesting activities. The emissions from these opera-
tions are generally significant but are usually not controlled except by
1-7
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.
operational (e.g., tilling) modifications. Since add-on controls are not
generally applicable to agricultural tilling, such will not be covered in
detail in this document.
Finally, control cost-effectiveness is defined in this document as the
dollars expended per unit mass of emissions reduced (i.e., $/Mg). Cost
effectiveness is a direct function of the initial capital investments as
well as the annualized costs of labor, operation, and maintenance. This
will be discussed in detail in Section 4.
1.2 REFERENCE DOCUMENTS
In order to develop appropriate control strategies for PMio, a number
of basic reference documents must be available to the person conducting the
analysis. These documents are listed in Table 1-4 in the order that they
appear in this handbook. It is strongly recommended that the user obtain a
copy of each of these reference documents prior to proceeding with any type
of analysis for the control of PMio- All of the documents listed are avail-
able either through the National Technical Information Service in Springfield,
Virginia, or from the EPA's Office of Air Quality Planning and Standards in
Durham, North Carolina.
1.3 ORGANIZATION OF HANDBOOK
The remainder of this document is organized as follows:
Section 2 - Quantification of Uncontrolled Emissions
Section 3 - Control Alternatives for PM1()
Section 4 - Estimation of Control Costs/Cost Effectiveness
Section 5 - Methods of Compliance Determination
1-8
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TABLE 1-4. LIST OF STANDARD REFERENCE DOCUMENTS
U.S. Environmental Protection Agency. Compilation of Air Pollutant Emis-
sion Factors. ^M Edition (4upp=l=ements=L-=l=§=}, AP-42, Office of Air
Quality Planning and Standards, Research Triangle Park, NC, •January;
U.S. Environmental Protection Agency. Control Techniques for Particulate
Emissions from Stationary Sources - Volumes 1 and 2. EPA-450/3-81-
005, Emission Standards and Engineering Division, Research Triangle
Park, NC, September 1982.
Cowherd, C. , et al. Identification, Assessment, and Control of Fugitive
Particulate Emissions. Final Report, EPA Contract No. 68-02-3922,
Midwest Research Institute, Kansas City, MO, April 1985.
Neveril, R. B. Capital and Operating Costs of Selected Air Pollution Con-
trol Systems. EPA-450/5-80-002, U.S. Environmental Protection Agency,
Research Triangle Park, NC, 1980.
1-9
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SECTION 2.0
QUANTIFICATION OF UNCONTROLLED EMISSIONS
In developing an uncontrolled emissions inventory, the large number of
individual sources and the diversity of source types make impractical the
field measurement of emissions at each point of release. Usually, the only
feasible method of determining pollutant emissions is to estimate the typi-
cal emissions for each of the source types.
In general, calculation of the estimated emission rate for a given
source requires data on production rate or source extent, the uncontrolled
emission factor and control efficiency. The mathematical expression for
this calculation is as follows:
R = Me (1 - c) (2-1)
where: R = mass emission rate
M = production rate or source extent
e = uncontrolled emission factor (i.e., rate of uncontrolled
emissions per unit of production or source extent)
c = fractional efficiency of control
The emission factor is an estimate of the rate at which a pollutant is re-
leased to the atmosphere from an uncontrolled source divided by the level
of production or source activity.
The document Compilation of Air Pollutant Emission Factors (AP-42),
published by the EPA since 1972, is a compilation of emission factor values
for the most significant source categories.1 As more information about
2-1
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sources and control of emissions has become available, supplements to AP-42
(1-15) have been published to include new emission source categories and
update existing source categories. Because the nation-wide effort to con-
trol industrial sources of pollution initially focused on discharge from
point sources, most of the factors compiled in AP-42 apply to point source
particulate emissions. However, with the increasing recognition of the im-
portance of fugitive particulate emissions, EPA has undertaken extensive
field testing to develop emission factors for fugitive sources.
The following sections briefly discuss the various emission factors
available to estimate the uncontrolled emissions from both point and fugi-
tive sources of
2.1 DUCTED SOURCE EMISSION FACTORS
As stated above, total particulate emission factors have been published
in AP-42 for ducted sources representing a multiplicity of industries and
processes. These factors are derived from data collected using standard
source sampling techniques such as EPA Method 5. The emission factors are
routinely expressed in terms of kilograms (kg) of pollutant emitted per
million (106) grams (Mg) of product.
Very little information is currently available in AP-42 relating to
applicable size-specific emission factors for various processes. Therefore,
it is frequently necessary to obtain additional test data on the typical
particle sizes associated with the emissions from a particular process to
obtain the uncontrolled emission rate of PM1().
To estimate the uncontrolled emission rate of PM10 from a particular
source, the total particulate emission factor contained in AP-42 is used in
Equation 2-2:
RIO = k ET P (2-2)
where: RXQ = emission rate of PM1() (kg/hr)
2-2
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k = cumulative mass fraction of^particulate emissions equal
to or less than 10 umA (%)
Ej = emission factor for total particulate matter (kg/Mg)
P = production rate (or other measure) rate of process opera-
tion (Mg/hr)
The term k in Equation 2-2 is determined from the cumulative particle size
distribution obtained from appropriate source tests of the process under
consideration.
Because of the above lack of emissions data, EPA has recently com-
pleted research to develop size-specific emission factors for selected
point sources. In this effort, revised AP-42 emission factors which spe-
cifically address PMio are being developed for various industrial processes.
The industries included in this program are: Portland Cement Manufacturing;
Lime Manufacturing; Asphaltic Concrete Plants; External Combustion; Pulp
and Paper Mills; Nonferrous Metallurgical Operations; Iron and Steel Pro-
duction; Ferroalloy Production; Gray Iron Foundries; and Metallurgical Coke
Production. Of those industries listed, the size-specific emission factors
for asphaltic concrete plants and pulp and paper mills are the most highly
refined and should be published in AP-42 sometime in the near future. The
remainder are still at various stages in the EPA peer review process.
Whenever size-specific emission factors are available, Equation 2-2
reduces to:
RIO = E10P (2-3)
where: EIQ = the emission factor for PMxo; and RIO and P are as
shown in Equation 2-2 above
2.2 PROCESS FUGITIVE EMISSION FACTORS
Applicable emission factors have also been published in AP-42 for pro-
cess fugitive emissions. As with ducted source emissions, Equations 2-2 and
2-3 shown above would likewise apply to process fugitive sources as well.
2-3
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In many instances, process fugitives are emitted into a building or
other enclosure and thus reach the atmosphere indirectly through various
openings such as roof monitors, windows, doors, etc. The sampling tech-
niques used to quantify such emissions are, therefore, much more difficult
to implement than is the case of ducted sources.2 Care should thus be exer-
cised whenever applying the appropriate emission factor for the various pro-
cess fugitive sources outlined in AP-42.
To assist the analyst in the above determination, one additional ref-
erence document might prove useful. This document is entitled, "Technical
Guidance for Control of Industrial Process Fugitive Particulate Emissions
(EPA-450/3-77-010)."3 Although this particular reference is somewhat dated,
it does discuss, in some detail, the emissions from various process fugitive
sources of interest.
Y
2.3 OPEN SOURCE EMISSION FACTORS
In 1972 under contract to EPA, Midwest Research Institute (MRI) ini-
tiated field testing programs to develop emission factors for four major
categories of open dust sources: aggregate storage piles, unpaved roads,
agricultural tilling, and heavy construction operations. Because the emis-
sion factors were to be applicable on a nation-wide basis, an analysis of
the physical mechanisms of fugitive dust generation was performed to ascer-
tain the parameters which would cause emissions to vary from one location to
another. These parameters were found to be grouped into three basic cate-
gories:
1. Measures of source activity or energy expended (e.g., the vertical
fall distance during a material transfer operation; vehicle weight and
speed on unpaved roads; etc.).
2. Properties of the material being disturbed (e.g., the amount of
suspendable fines (or silt) and moisture content of the material being
dropped).
2-4
-------
3. Climatic parameters (e.g., the wind speed to which the material is
exposed).
Uncontrolled emissions within a single generic source category may
vary over two (or more) orders of magnitude as a result of variations in f/>
/•. ~ i * t
source conditions (equipment characteristics, material properties,
^t?
climatic parameters). Therefore, an entire generic source category^eafinot
be represented in terms of a single-valued emission factor as is/fjthe case
for ducted sources. Rather, a large matrix of single-valued factors is
necessary to adequately represent an entire open dust source category. In
order to account for the variability in emissions, fugitive dust emission
factors were constructed as mathematical equations for sources grouped by
dust generation mechanism. The emission factor equation for each source
category contains correction terms which explain much of the variance in
observed emissions on the basis of specific source parameters. Such fac-
tors are applicable to a wide range of source conditions, limited only by
the extent of experimental verification.
For example, the use of the silt content as a measure of the dust gen-
eration potential of a material extends the applicability of the emission
factor equations to the wide variety of aggregate materials of industrial
importance. The silt content is obtained by dry sieving through a 200 mesh
screen according to ASTM Method C-136. The upper size limit of silt par-
ticles (74 urn in physical diameter) is the smallest particle size for which
size analysis by dry sieving is practical, and is also a reasonable estima-
tion of the upper size limit for particles which can become airborne.
In 1975, EPA published a new section of AP-42 (Section 11.2) dealing
with fugitive dust sources on a generic basis and incorporating newly de-
veloped emission factors. The original source categories included unpaved
roads, agricultural tilling, and aggregate storage piles. As a result of
the increased rate of open dust source test data accumulation after 1975
and the development of improved emission "factors, EPA published a major up-
date and expansion of Section 11.2 (Supplement 14) in May 1983. This in-
cluded improved emission factor equations for unpaved roads, agricultural
2-5
-------
tilling, industrial paved roads, aggregate storage piles, and materials
handling (including batch and continuous drop operations). The agricultural
tilling equation was again updated in Supplement 15 published in January of
1984.
With each of the new fugitive emission factors was provided a set of
correction parameters for adjusting calculated emission values to specific
particle size fractions. The largest factor corresponds to particles equal
to or less than 30 pm in aerodynamic diameter corresponding to the approxi-
mate effective cutpoint of the standard high-volume sampler (i.e., total
suspended particulate matter or TSP). A size factor for particles equal to
or less than 10 urn aerodynamic diameter is also provided, which is directly
applicable to EPA's proposed revision to the primary NAAQS.
2.3.1 Predictive Emission Factor Equations
The following sections describe the current (or soon to be published)
AP-42 emission factor equations applicable to the following fugitive dust
source categories: unpaved roads, paved roads, aggregate handling and
storage piles, and construction operations. Also discussed are appropriate
correction parameters to be used as input to the equations. References to
the origin of the equations and supporting information are (or will be)
provided in AP-42.
2.3.1.1 Unpaved Roads—
The following empirical expression may be used to estimate the quantity
of particulate emissions from an unpaved road per unit of vehicle travel:1
E = 1.7k
E = 5.9k
0.7
0.7
vO.5
\0.5
(kg/VKT)
(Ib/VMT)
(2-4a)
(2-4b)
2-6
-------
where: E = emission factor (kg/VKT or Ib/VMT)
i
k = particle size multiplier (dimensionless) = 0..45 for PMio
s = silt content of road surface material (%)
S = mean vehicle speed (km/hr or mph)
W = mean vehicle weight (Mg or tons)
w = mean number of wheels (dimensionless)
p = number of days with at least 0.254 mm (0.01 in.) of precipita-
tion per year
The number of wet days per year (p) for the geographical area of in-
terest should be determined from local climatic data. Figure 2-1 gives the
geographical distribution of the mean annual number of wet days per year in
the United States.
Equation 2-4 has an A quality rating if applied within the ranges of
source conditions that were tested in developing the equation, as shown in
Table 2-1. Also, to retain the quality rating of Equation 2-4 applied to a
specific unpaved road, it is necessary that reliable correction parameter
values for the specific road in question be determined. The field and labo-
ratory procedures for determining road surface silt content are given in
Appendices A and B and for determining traffic and vehicle characteristics
in Appendix C.
^
and thus ,_js_jtp^gynRLtiP-1 jje.d_by_ann uaJ^sAu^ce^ext .e.gt^lti^vg.hlcle^ d (stance
=~ ~ ~ : ~ ~
Annual average values for each of the correction parameters
are to be substituted into the equation.
in£ to dryjroad c^jidiiJ:j\ojisj._iMy^e_c_alcLLlated by
tions (which is equivalent to dropping the last term from the equations).
— =—
A sej}aj^jy|jjtsofnpj£^ a V
* ~ — "- — — - ' — -- -,--.,..-.—- ___ __ _ _^_^.— -rr-— - ___— - -•» Sfy>^
/BLvalue may also be justified for the worst case averaging period (usually
24 ========~==™=—=== =====
2-7
-------
ro
i
CO
180
HP
IS!
• so too 2oa 301 400 so*
210
141
MILES
Figure 2-1. Mean number of days with 0.01 in. or more of precipitation in United States.1
-------
TABLE 2-1. RANGE OF SOURCE CONDITIONS FOR EQUATION 2-4a
Road
surface silt
content
(%)
Mean vehicle
Mg
weight
tons
Mean vehicle
speed
km/hr
mph
Mean
No. of
wheels
4.3-20 2.7-142 3 - 157 21-64 13-40 4 - 13
a Values must be in the stated ranges to maintain A quality
rating. Reference 1.
Similarly, to calculate emissions for a 91 day season of the year using
Equation 2-4, replace the term (365-p)/365 with the term (91-p)/91, and set
p equal to the number of wet days in the 91 day period. Also, use appro-
priate seasonal values for the nonclimatic correction parameters and for
VDT.
2.3.1.2 Paved Roads—
The quantity of particulate emissions generated by vehicle traffic on
dry, industrial paved roads, per unit of vehicle travel, may be estimated
using the following empirical expression:
/ \ / \ / \07
E =,4M*5*. U ' (kg/VKT) (2-5a)
/\ / \ / , \ AA0.7
E =
-------
The industrial road augmentation factor (I) in the equation is an em-
pirical factor which takes into account higher emissions from industrial
roads than from urban roads. I = 7.0 for an industrial roadway which traf-
fic enters from unpaved areas. 1-3.5 for an industrial roadway with un-
paved shoulders which are trave4ed by 20% of the traffic. I = 1.0 for
cases in which traffic does not travel on unpaved areas. A value of I be-
tween 1.0 and 7.0 should be used in the equation which best represents con-
ditions for paved roads at a certain industrial facility (see Appendix C
for details on the determination of I).
The equation has a quality rating of B if applied to vehicles traveling
entirely on paved surfaces (I = 1.0) and if applied within the range of
source conditions that were tested in developing the equation as shown in
Table 2-2.
TABLE 2-2. RANGE OF SOURCE CONDITIONS FOR EQUATION 2-5a
Silt
content
(%)
Surface
kg/ km
loading
Ib/mile
No. of
lanes
Vehicle weight
Mg tons
5.1 - 92 42.0 - 2,000 149 - 7,100 2-4 2.7-12 3-13
a Values must be in the stated ranges to maintain a B quality rating
with 1=1. Reference 1.
If I > 1.0, the rating of the equation drops to D because of the arbi-
trariness in the guidelines for estimating I (see Appendix C). Also, to
retain the quality ratings of Equation 2-5 applied to a specific industrial
paved road, it is necessary that reliable correction parameter values for
the specific road in question be determined. The field and laboratory pro-
cedures for determining surface material silt content and surface dust load-
ing are given in Appendices A and B.
2-10
-------
For urban paved roads, a revised emission factor equation has been
developed which should be published in AP-42 in the very near future.4 The
quantity of PM10 generated by vehicle traffic on an urban paved roadway per
vehicle kilometer traveled (VKT) may be estimated using the following em-
pirical expression4:
/sL\ °'8
E = 2.28(j}U (2-6)
where: E = PMio emission factor (g/VKT)
S = surface material silt content (%)
L = total surface dust loading (g/m2)
For most emissions inventory applications involving urban paved roads,
actual measurements of silt loading will probably not be made. Therefore,
to facilitate the use of the previously described equation, it is necessary
to characterize silt loadings according to parameters readily available to
persons developing the inventories. It is convenient to characterize vari-
ations in silt loading with a roadway classification system presented in
Table 2-3.4 This system generally corresponds to the classification sys-
tems used by transportation agencies, and thus the data necessary for an
emissions inventory (number of road miles per road category and traffic
counts) should be easy to obtain. In some situations, it may be necessary
to combine this silt loading information with sound engineering judgment in
order to approximate the loadings for roadway types not specifically in-
cluded in Table 2-3.
A data base of 44 samples analyzed according to consistent procedures
may be used to characterize the silt loadings for each roadway category.4
These samples, obtained during recent field sampling programs, represent a
broad range of urban land use and roadway conditions. Geometric means
for this data set are given by sampling location and roadway category in
Table 2-4.4
2-11
-------
TABLE 2-3. PAVED URBAN ROADWAY CLASSIFICATION'
Roadway category
Freeways/expressways
Major streets/highways
Collector streets
Local streets
Average daily traffic
(ADT)
> 50,000
> 10,000
500 - 10,000
< 500
No.
of
Lanes
^ 4
^ 4
2b
2C
Reference 4.
Road width £ 32 ft.
Road width < 32 ft.
TABLE 2-4. SUMMARY OF SILT LOADING (sL) VALUES FOR PAVED URBAN ROADWAYS'
Roadway category
Local Collector Major streets/ Freeways/
streets streets highways expressways
City X" (g/m2) n X" (g/m2)
Q Q
Baltimore 1.42 2 0.72
Buffalo 1.41 5 0.29
Granite City (IL) -
Kansas City - - 2.11
St. Louis -
All 1.41 7 0.92
n Xq(g/m2)
4 0.39
2 0.24
0.82
4 0.41
0.16
10 0.36
n Xq(g/m2)
3
4
3
13
3 0.022
26 0.022
n
-
-
-
-
1
1
Reference 4. X = geometric mean based on corresponding n sample size.
2-12
-------
The sampling locations shown in Table 2-4 can be considered represen-
tative of most large urban areas in the United States, with the possible
exception of those in the Southwest. Except for the collector roadway
category, the mean silt loadings do not vary greatly from city to city,
though the St. Louis mean for major roads is somewhat lower than those of
the other four cities. The substantial variation within the collector
roadway category is probably attributable to the effects of land use around
the specific sampling locations. It should also be noted that an examina-
tion of data collected at three cities in Montana during early spring indi-
cates that winter road sanding may produce loadings five to six times higher
than the means of the loadings given in Table 2-4 for the respective road
categories.4
Finally, TaJ^jjJ?rJL^&sjejits^^
obtai ned by i nse.rting=themmean^s:iJ-t-Jj)adi nqs i n Ta^Te_j^4intoEqu£t^oji 2^6 .
These emission factors can be used directly for many emission inventory pur-
poses.
TABLE 2-5. RECOMMENDED PM10 EMISSION FACTORS
FOR SPECIFIC ROADWAY CATEGORIES3
Emission
Roadway category factor (g/VKT)
Local streets 5.2
Collector streets 3.7
Major streets/highways 1.8
Freeways/expressways 0.19
a Reference 4.
2-13
-------
2.3.1.3 Aggregate Handling and Storage Piles--
Total dust emissions from aggregate storage piles are contributions of
several distinct activities within the storage cycle:
1. Loading of aggregate onto storage piles (batch or continuous drop
operations).
2. Equipment traffic in storage area.
3. Wind erosion of pile surfaces and ground areas around piles.
4. Loadout of aggregate for shipment or for return to the process
stream (batch or continuous drop operations).
Adding aggregate material to a storage pile or removing it usually in-
volves dropping the material onto a receiving surface. Truck dumping on
the pile or loading out from the pile to a truck with a front end loader
are examples of batch drop operations. Adding material to the pile by a
stacker conveyor is an example of a continuous drop operation.
The quantity of parti cul ate generated by a batch drop operation per
ton of material transferred may be estimated using the following empirical
expression: 1
U \ / H
/ U \ / H \
E = 0.0009k P^ (kg/Mg) (2-7a)
/M/
(z)
s\ /U\ /H\
E = 0.0018k SM5/ \5/ (ib/ton) (2-7b)
(5) (I)
where: E = emission factor (kg/Mg or Ib/ton)
k = particle size multipler (dimensionless) = 0.36 for PM10
s = material silt content (%)
U = mean wind speed (m/s or mph)
H = drop height (m or ft)
M = material moisture content (%)
Y = dumping device capacity (m3 or yd3)
2-14
-------
The quantity of participate emissions generated by a continuous drop
operation per ton of material transfi|rre^ may be estimated using the fol-
lowing empirical expression:1 ^
s\ / U \ / H \
E = 0.0009k 5; l?727 lO/ (kg/Mg) (2-8a)
(5)
/s\ /U\ / H\
w 157 \W
E = 0.0018k VJ/ v% vxu/ (Ib/ton) (2-8b)
/M/
where: E = emission factor (kg/Mg or Ib/ton)
k = particle size multiplier (dimensionless) = 0.37 for PM10
s = material silt content (%)
U = mean wind speed measured at 4 m (m/s or mph)
H = drop height (m or ft)
M = material moisture content (%)
Equations 2-7 and 2-8 carry a quality rating of C if applied within the
ranges of source conditions that were tested in developing the equations as
given in Table 2-6.1 Also, to retain the quality ratings as applied to a
specific facility, it is necessary that reliable correction parameters be
determined for the specific sources of interest. The field and laboratory
procedures for aggregate sampling are given in Appendices A and B. In the
event that site-specific values for correction parameters cannot be ob-
tained, the appropriate mean values from Table 2-6 may be used, but the
quality ratings of the equations are reduced to D.
For emissions from equipment traffic (trucks, front end loaders, doz-
ers, etc.) traveling between or on piles, it is recommended that the equa-
tion for vehicle traffic on unpaved surfaces be used (see Section 2.3.1.1).
For vehicle travel between storage piles, the silt value(s) for the areas
among the piles (which may differ from the silt values for the stored mate-
rials) should be used.
2-15
-------
TABLE 2-6. RANGES OF SOURCE CONDITIONS FOR
EQUATIONS 2-7 and 2-8a
Silt Moisture
Equation content content Dumping capacity Drop height
(%) (%) ~m* yd-* m ft
Batch drop 1.3-7.3 0.25 - 0.70 2.10 - 7.6 2.75 - 10
Continuous
drop 1.4 - 19 0.64 - 4.8 NA NA 1.5 - 12 4.8 - 39
a Values must be in the stated ranges to maintain a C quality rating.
NA = not applicable. Reference 1.
For emissions from wind erosjjn_o£=;jctj^e==£tpj^age_pjjes^> no PMio
emi ss i on f 'actQMj_a_vaL1able. _ln_APrA2 . The following emission factor equa-
tion is recommended for TSP (particles smaller than approximately 30
= L9 o n is (kg/day/hectare) (2-9a)
Ob/day/acre) (2-9b)
where: E = emission factor
s = silt content of aggregate (%)
p = number of days with ^ 0.25 mm (0.01 in.) of precipitation per
year
f = percentage of time that the unobstructed wind speed exceeds
5.4 m/s (12 mph) at the mean pile height
The coefficient in Equation 2-9 is based on field sampling of emissions
from a sand and gravel storage pile area during periods when transfer and
maintenance equipment was not operating. Equation 2-9 is rated C for ap-
plication in the sand and gravel industry and D for other industries.
Worst case emissions from storage pile areas occur under dry windy con-
ditions. Worst case emissions from materials handling (batch and continuous
2-16
-------
drop) operations may be calculated by substituting into Equations 2-7 and
2-8 appropriate values for aggregate moisture content and for anticipated
wind speeds during the worst case averaging period (usually 24 hr). The
treatment of dry conditions for vehicle traffic (Equation 2-4) and for wind
erosion (Equation 2-9), centering around parameter p, follows the methodol-
ogy described in Section 2.3.1.1. Also, a separate set of nonclimatic cor-
rection parameters and soyrce jxtent values corresponding to higher than
normal storage .-.pile, activity may be justified for the worst case averaging
period....
2.3.2 Heavy Construction Operations
Heavy construction is a source of dust emissions that may have substan-
tial temporary impact on local air quality. Building and road construction
are the prevalent construction categories with the highest emissions poten-
tial. Emissions during the construction of a building or road are associated
with land clearing, blasting, ground excavation, cut and fill operations, and
the construction of the particular facility itself. Dust emissions vary sub-
stantially from day to day depending on the level of activity, the specific
operations, and the prevailing weather. A large portion of the emissions
result from equipment traffic over temporary roads at the construction site.
In estimating the emissions from heavy construction operations, it is
necessary to subdivide the site activities into operational steps. Then
the emissions from each step are calculated using the emission factor equa-
tion that is most applicable. Fortunately, Equation 2-4 is applicable to
the typically predominant source (i.e., equipment traffic over unpaved sur-
faces at the construction site). It should be noted that an important
jgcqndary^impact of construction_operations results^ from mud carryout^ and_ d<>
increased dirt loadings pn paved_ roads adjacent to the construction site.
MRI has recently conducted studies of both the emissions generated by
construction vehicles and the secondary impacts due to mud/dirt carryout.5'6
During the first study, an empirical relationship was developed which pre-
dicts the downwind concentration of TSP, IP (particles ^ 15 umA), and PM10
2-17
-------
as a function of surface properties and vehicular traffic. The average un-
controlled emission factor developed in the study for TSP was 7.92 kg/
vehicle km (28.1 Ib/VMT) which would approximately equal 1.6 kg/vehicle km
(5.6 Ib/VMT) for PMi0.5
In the second program, the overall increase in emissions due to mud/
dirt carryout was estimated for paved roads located adjacent to eight ac-
tive construction sites in the Minneapolis/St. Paul area. An analysis was
conducted using surface samples collected in the field in conjunction with
Equation 2-6 above.6 The results of the study indicated an average emis-
sions increase for PM10 to be 12 g/vehicle pass for all eight sites sampled
encompassing residential and commercial construction.6
2.3.3 Determination of Correction Parameters
Use of the predictive equations presented in Section 2.3.1 improves the
accuracy of emission factor estimation over that obtained with single-valued
emission factors but requires values for the various correction parameters.
The generally higher quality ratings assigned to the equations are ap-
plicable only if: (1) reliable values of correction parameters have been
determined for the specific sources of interest; and (2) the correction
parameter values lie within the ranges tested in developing the equations.
Determination of reliable aggregate and surface material properties re-
quires sampling and analysis of the actual source materials using the tech-
niques referenced in AP-42. Those techniques are described in Appendices A
and B. In the event that the source materials cannot be sampled (e.g., in
the case of a proposed new facility), a limited number of default values may
be obtained from the tables presented in AP-42. However, use of a default
value from these tables reduces the quality rating of J,he emission factor
estimate by one level.
2-18
-------
Tables 2-7, 2-8, and 2-9 present ranges and mean correction parameter
values for unpaved road surface materials, industrial paved road surface
materials, and industrial aggregate materials, respectively.1'4 Mean values
of the correction parameters provided in these tables can be used as appro-
priate default values only if:
1. It is impractical or impossible to determine specific correction
parameters.
2. Values are available for the industry (and material) in question.
3. There is no reason to believe that the source in question will be
atypical of existing sources in the specified industry.
It is generally not permissible to use other than the mean value of the
parameter unless some justification is available.
TABLE 2-7. TYPICAL SILT CONTENT VALUES OF SURFACE MATERIALS ON
INDUSTRIAL AND RURAL UNPAVED ROADS1
Industry
Road use or
surface material
No. of test
samples
Silt (
Range
'0/\
>;
Mean
Iron and steel
production
Taconite mining and
processing
Western surface coal
mining
Rural roads
Plant road
Haul road
Service road
Access road
Haul road
Scraper road
Haul road
(freshly graded)
Gravel
Dirt
13
12
8
2
21
10
5
2
1
4.3 13
3.7 -
2.4 -
4.9 -
2.8 -
7.2 -
18 -
12
9.7
7.1
5.3.
18 --
25-
29 —
13
5.8
4.3
5.1
8.4
17
24
12
68
2-19
-------
ro
ro
o
TABLE 2-8. TYPICAL SILT CONTENT AND LOADING VALUES FOR PAVED ROADS
AT INDUSTRIAL FACILITIES3
Industry
Copper smelting
Iron and steel
production
Asphalt batching
Concrete batching
Sand and gravel
processing
No. of
plant sites
1
6
1
1
1
No. of
samples
3
20
4
3
3
Silt (%,
Range
[15.4-21.7]
1.1-35.7
[2.6-4.6]
[5.2-6.0]
[6.4-7.9]
w/w)
Mean
[19.0]
12.5
[3.6]
[5.5]
[7.1]
No. of h
travel Total loading x 10 3°
lanes Range
2 [12.9-19.5]
[45.8-69.2]
2 0.006-4.77
0.020-16.9
1 [12.1-18.0]
[43.0-64.0]
2 [1.4-1.8]
[5.0-6.4]
1 [2.8-5.5]
[9.9-19.4]
Mean
[15.9]
[55.4]
0.495
1.75
[15.7]
[55.7]
[1.7]
[5.9]
[3.8]
[13.3]
Units
kg/ km
Ib/mi
kg/km
Ib/mi
kg/km
Ib/mi
kg/km
Ib/mi
kg/km
Ib/mi
Silt loading
(g/m2)
Range
[188-400]
< 1.0-2.3
[76-193]
[11-12]
[53-95]
Mean
[292]
7
[138]
[12]
[70]
Reference 4. Brackets indicate values based on samples obtained at only one plant site.
Multiply entries by 1,000 to obtain stated units.
-------
TABLE 2-9. TYPICAL SILT AND MOISTURE CONTENT VALUES OF MATERIALS
AT VARIOUS INDUSTRIES1
ro
ro
Industry
Iron and steel
production
Stone quarrying
and processing
Taconite mining
and processing
Western surface
coal mining
Material N
Pellet ore
Lump ore
Coal
Slag
Flue dust
Coke breeze
Blended ore
Sinter
Limestone
Crushed limestone
Pellets
Tailings
Coal
Overburden
Exposed ground
Silt
o. of test
samples
10
9
7
3
2
1
1
1
1
2
9
2
15
15
3
1
2
1
2
3
3
5
fl
0
Range
.4
.8
2
3
14
.3
.2
.4
.8
.1
- 13
- 19
- 7.7
- 7.3
- 23
- 1.9
- 5.4
NA
- 16
- 15
- 21
\
Mean \
4.
9.
5
5.
18.
5.
15.
0.
0.
1.
3.
11.
6.
7.
15.
9
5
3
0
4
0
7
4
6
4
0
2
5
0
Moisture (%)
No. of test
samples Range
\
8
6
6
3
0
1
1
0
0
2
7
1
7
0
3
0.64 -
1.6 -
2.8 -
0.25 -
NA
NA
NA
0.3 -
0.05 -
2.8 -
NA
0.8 -
3.5
8.1
11
2.2
1.1
2.3
20
6.4
Mean
2.1
5.4
4.8
0.92
NA
6.4
6.6
NA
NA
0.7
0.96
0.35
6.9
NA
3.4
-------
To provide some further guidance in selecting representative correction
parameters for vehicle characteristics, wind speeds, drop heights, and dump-
ing capacities, Tables 2-10, 2-11, and 2-12 are typical values determined
during various field testing programs.7 20 These may also be used to esti-
mate appropriate inputs for similar operations where no actual data are
available.
2-22
-------
TABLE 2-10. TYPICAL CORRECTION PARAMETERS DETERMINED FOR UNPAVED ROADS
Type of
Industry vehicular traffic
Iron and steel Industrial heavy-duty
vehicles
Industrial light-duty
Industrial medium-duty
Average vehicle mix
(light, med. , heavy)
ro
ro Taconite mining and Heavy-duty traffic/
00 processing haul trucks
Heavy-duty traffic/
average vehicle mix
Western surface Vehicle traffic/light-
coal mining and medium duty
processing
Vehicle traffic/haul
trucks
Scrapers/travel mode
Grading
Vehicle traffic/haul
Vehicle
speed
(km/hr)
23-48
24
35-47
11-18
24-32
22
40-69
24-58
16-51
8.1-19
35-39
Vehicle
weight
(Mg)
21-64
3-4
7-27
Light- heavy
61-143
106-107
1.8-2.4
22-125
33-64
12-13
a
Average
No. of
wheels Reference No.
4-8 7
4 8
6-13
9
6 11
6
4.0-4.1 13
4.9-10
4.0-4.1
5.9-6.0
14
Comments
Scraper
Grader
trucks
(continued)
-------
TABLE 2-10. (concluded)
ro
i
ro
Industry
Generic unpaved roads
Agricultural tilling
Type of
vehicular traffic
Vehicle traffic
Truck traffic/haul
roads
Vehicle traffic
Vehicle trafficd
Vehicle traffic
Agricultural tilling/
tractor speed
Vehicle
speed
(km/hr)
24-64
16-40
16-81
21-64
11-27
5-8f
Vehicle
weight
(Mg)
2-3b
3.9-7.5
2-3c
3-142
Light- heavy6
Average
No. of
wheels
4
6
4
4-13
Reference No. Comments
15
16
17
18
9
19 Disc, land plane,
sweep plow
Information not contained in report.
Actual weights not stated; assume a normal traffic mix weight of 2 to 3 tons.
Test report states normal traffic mix; therefore, the weight range is assumed to be 2 to 3 tons.
Tests were conducted during four different studies ranging from 1973 to 1979.
Actual weights were not assigned to the vehicle weight categories.
Tractor speed.
-------
TABLE 2-11. TYPICAL CORRECTION PARAMETERS DETERMINED FOR INDUSTRIAL PAVED ROADS
ro
en
Industry
Iron and steel
Asphalt
batching
Concrete
batching
Copper smelting
Sand and gravel
processing
Paved roads
Type
of road
Haul road
Haul road
Haul road
Haul road
Haul road
Haul road
Haul road
Industrial
road
Type of augmentation
vehicular traffic factor
Average vehicle mix
Li ght/med. /heavy
Light/med. /heavy
Med. duty
Med. duty
Med. duty
Heavy duty
Vehicle traffic
NA
NA
NA
NA
NA
NA
1-7
No. of
lanes
2
2
1
2
2
1
2-4
Average ve-
hicle weight
(Mg)
6-7
5-12
3.6-3.8
8.0
3.1-7.0
39-42
3-12
Reference No.
7
8
20
20
20
20
8
This parameter takes into account higher emissions from industrial roads as compared to urban roads.
NA = not available.
I = 7.0 for trucks coming from unpaved to paved roads and releasing dust from vehicle underbodies.
I = 3.5 when 20% of the vehicles are forced to travel temporarily with one set of wheels on an
unpaved road berm while passing on narrow roads.
I = 1.0 for traffic entirely on paved surfaces.
-------
TABLE 2-12. TYPICAL CORRECTION PARAMETERS DETERMINED FOR AGGREGATE HANDLING AND STORAGE PILES*
ro
ro
en
Type of Type of process
Industry operation Batch Continuous
Iron and steel High-silt X
processed
slag/load-
out
Low silt X
processed
slag/load-
out
Ore pile X
stacking/
mobile
conveyor
stacker
Ore pile X
stacking/
mobile
conveyor
stacker
Conveyor X
transfer
station
Storage X
pile/
mobile
stacker
Storage X
pile
stacking/
mobile
stacker
Dumping
Wind Drop device
Type of speed height capacity
material (m/sec) (m) (m3) Reference No. Comments
Slag 0.98-1.9 1.5 7.7b 7
Slag 0.58-1.4 1.5 7.7b
Iron ore 1.0-2.0 1.5-4.5 A//4
pellets
Lump ore 0.81-0.98 1.5-4.5 ft A
(desert mound
and open
hearth)
Sinter Calm 1.1-2.2 ft ft
Iron pellets 0.67-2.7 9-12 fifi 8
Coal 1.3 5 fi-'A
(continued)
-------
TABLE 2-12. (continued)
Industry
Sand and gravel
storage
-
Stone quarrying
and processing
Type of Type of process Type of
operation Batch Continuous material
Active X Sand and
pile ac- gravel
tivities/
stock
piles/
load- in
and
load-out
Inactive Sand and
wind gravel
erosion
periods/
load-in
and load-
out of
stockpile
material
Normal mix X Sand and
of active gravel
and in-
active
periods/
load-in
and load-
out of
material
stockpiles
Crushed X Crushed
stone limestone
storage
piles/high
loader/
dump truck
Dumping
Wind Drop device
speed height capacity
(m/sec) (m) (m3) Reference No. Comments
1.1-11.2 1.5 /V4 18 • Activity 8-12 hr/24 hr
• Wind erosion of pile
surfaces and ground
area between piles
24 hr
• Equipment traffic in
storage area
• Maintenance
1.1-8.27 1.5 /V^ • Equipment traffic in
storage area
• Wind erosion of pile
surfaces and ground
area between piles
1.1-11.2 1.5 /VV3- • Equipment traffic in
storage area
• Wind erosion of pile
surfaces and ground
area between piles
• Assumes 5 active days
per week
5.63-6.26 1.5 2 18
(continued)
-------
TABLE 2-12. (concluded)
ro
CO
Industry
Western surface
coal mining and
processing
Aggregate stor-
age piles
and material
handling
Type of Type of process
operation Batch Continuous
Dragline X
Dragline X
Dragline X
Dragline X
Front end X
loader/
shovel
truck
Dragline X
Batch X
load-in
Storage X
pile
formation/
stacker
conveyor/
load- in
Type of
material
Overburden
Overburden
Overburden
Overburden
Coal loading
Overburden
Steel slag,
crushed lime-
stone
Coal, lump
iron ore,
pellets
Wind
speed
(m/sec)
0.18-0.80
1.4-2.6
1.6-2.4
2.6-3.2
0.98-5.01
0.98-7.42
0.58-6.26
0.67-2.7
Drop
height
(m)
NA
NA
NA
NA
NA
2-30
1.5
1.5-12
Dumping
device
capacity
(m3) Reference No.
14 12
57
46
25
11-13 13
25-50
2.10-7.65 7
f-M 8
Comments
Test conducted in
northwest Colorado
Test conducted in
southwest Wyoming
Test conducted in
southeast Montana
Test conducted in
central North Dakota
Example: front-end
loader to truck
NA = not available.
Front end loader into 35-ton capacity truck.
-------
REFERENCES FOR SECTION 2
1. U.S. Environmental Protection Agency. Compilation of Air Pollutant
Emission Factors. 4^ Edition (=Supp=l=ements=l=i=5^, AP-42, Office of
Air Quality Planning and Standards, Research Triangle Park, NC, 4anua-ry
, i>
-------
9. Maser, J. A. and C. L. Norton. Uncontrolled and Controlled Emissions
from Nontraditional Sources in a Coke and Iron Plant: A Field Study
Analysis. Presented at the Air Pollution Control Association Specialty
Conference on Air Pollution Control in the Iron and Steel Industry,
Chicago, IL, April 1981.
10. Pacific Environmental Services. Fugitive Dust Assessment at Rock and
Sand Facilities in the South Coast Air Basin. Draft Final Report,
Southern California Rock Products Association and Southern California
Ready-Mix Concrete Association, Los Angeles, CA, November 1979.
11. Cuscino, T. A., Jr., et al. Taconite Mining Fugitive Emission Study.
Minnesota Pollution Control Agency, Roseville, MN, June 1979.
12. PEDCo Environmental. Survey of Fugitive Dust from Coal Mines. EPA-
908/1-78-003, U.S. Environmental Protection Agency, Region VIII,
Denver, CO, February 1978.
13. Axetell, K., Jr. and C. Cowherd, Jr. Improved Emission Factors for
Fugitive Dust from Western Surface Coal Mining Sources, Volumes 1 and
2. EPA-600/7-84-048, U.S. Environmental Protection Agency, Cincinnati,
OH, March 1984.
14. Shearer, D. L., et al. Coal Mining Emission Factor Development and
Modeling Study. Amax Coal Company, Carter Mining Company, Sunoco
Energy Development Company, Mobile Oil Corporation, and Atlantic
Richfield Company, Denver, CO, July 1981.
15. Jutze, G. and K. Axetell. Investigation of Fugitive Dust, Volume I -
Sources, Emissions, and Control. EPA-450/3-74-036a, U.S. Environ-
mental Protection Agency, Research Triangle Park, NC, June 1974.
16. Dyck, R. J. and J. J. Stukel. Fugitive Dust Emissions from Trucks on
Unpaved Roads. Environmental Science and Technology, 10(10):1046-1048,
October 1976.
2-30
-------
17. McCaldin, R. 0. and K. J. Heidel, "Particulate Emissions from Vehicle
Travel over Unpaved Roads," presented at the 71st Annual Meeting of
the Air Pollution Control Association, Houston, TX, June 1978.
18. Cowherd, C. , et al. Development of Emission Factors for Fugitive Dust
Sources. EPA-450/3-74-037, U.S. Environmental Protection Agency, Re-
search Triangle Park, NC, June 1974.
19. Cuscino, T. A., Jr., et al. The Role of Agricultural Practices in
Fugitive Dust Emissions. Final Report, CARB Contract No. A8-125-31,
Midwest Research Institute, Kansas City, MO, June 1981.
20. Reider, J. P. Size Specific Particulate Emission Factors for Uncon-
trolled Industrial and Rural Roads. Final Report, EPA Contract No.
68-02-3158, Technical Directive No. 12, Midwest Research Institute,
Kansas City, MO, September 1983.
fff- 6Jr U.S.
2-31
-------
3.0 CONTROL ALTERNATIVES FOR PM10
From Equation 2-1, it is clear that more than one option for reduction
of the uncontrolled emission rate can be considered. To begin with, the
uncontrolled emission rate is the product of the production rate or source
extent and the applicable uncontrolled emission factor. A reduction in
either of these variables produces a proportional reduction in uncontrolled
emissions.
Although the reduction of production or source extent results in a
highly predictable reduction in the uncontrolled emission rate, such an ap-
proach usually requires either a reduction or change in the process opera-
tion. Frequently, reduction in the extent of one. source may. necessitate
the increase in the extent of another (e.g. shifting of vehicle traffic
from an unpaved road to a paved road). The option. of reducing production
or source extent is very site specific a'nd- i-s t-hus beyond-th'e -scope of this
jnanua.l _____ Ih.e.ne.f_o.re.,~such -mea'sures-wi-H not- be-
A reduction in the uncontrolled emission factor may be achieved by
process modifications (in the case of a process) or by adjusted work prac-
tices (in the case of open sources). The key to the possible reduction of
the uncontrolled emission factor is the knowledge as to how the emissions
depend on the source conditions that might be subject to alteration. For
open dust sources, this information is embodied in the predictive emission
factor equations for fugitive dust sources as presented in Section 2 ^ above,
Again, modifications to either the process or in work practices are site
specific and thus will not be covered here.
3-1
-------
The following sections present various "add-on" alternatives for the
control of PMio emissions from both ducted and fugitive sources. The in-
dividual methods will be described followed by available control efficiency
data for each technique.
3.1 CONTROL ALTERNATIVES FOR DUCTED SOURCES
The control of ducted source PM10 emissions involves the application
of traditional industrial gas cleaning technology. This technology can be
classified into four major categories: mechanical dust collectors; elec-
trostatic precipitators; fabric filters; and wet scrubbers. Devices in
each category will be briefly described in this section along with typical
size-specific performance data for the collection of PMio- The EPA Control
Techniques document listed in Table 1-4 will be utilized as the prime ref-
erence in the following discussion.1
In addition to the EPA Control'Techniques document mentioned above,
there are also a number of other standard references which contain specific
information on the design and performance of industrial gas cleaning equip-
ment. These references are listed in Table 3-1. The reader is encouraged
to consult the documents shown in Table 3-1 for other data pertinent to the
engineering design, theory, and collection efficiency associated with vari-
ous types of point source controls.
3.1.1 Mechanical Dust Collectors
Mechanical collectors comprise a broad class of particulate control
devices that utilize gravity settling and dry inertial impaction mechanisms.
Because their performance capability is limited to relatively large parti-
cles, the use of mechanical collectors for the control of PM10 is limited.
Thus, mechanical collectors are usually used primarily as precleaners up-
stream of more efficient devices. Mechanical collectors are reasonably
tolerant of high dust loadings, are not susceptible to frequent malfunction
if properly designed and operated, and could be adequate control devices
for some limited applications.
3-2
-------
TABLE 3-1. STANDARD REFERENCE DOCUMENTS FOR INDUSTRIAL
GAS CLEANING EQUIPMENT
Strauss, W. Industrial Gas Cleaning. 2nd Edition, Pergamon Press, Oxford,
1975.
Theodore, L., and A. J. Buonicore. Industrial Air Pollution Control Equip-
ment for Participates. CRC Press, Cleveland, OH, 1976.
Stern, A. C., et al. Cyclone Dust Collectors. American Petroleum Insti-
tute, New York, February 1955.
White, H. J. Industrial Electrostatic Precipitation. Addison-Wesley Pub-
lishing Company, Reading, MA, 1963.
Davies, C. N. Air Filtration. Academic Press, New York, 1973.
Calvert, S., et al. Wet Scrubber System Study, Volume I: Scrubber Hand-
book. EPA-R2-72-118a, U.S. Environmental Protection Agency, Research
Triangle Park, NC, August 1972.
There is great diversity in the design and operation of the various
types of mechanical collectors. Table 3-2 lists the major types of mechani-
cal dust collectors and the mechanism(s) of particle capture for each type.
The following is a brief description of the various mechanical collectors
listed in Table 3-2.
TABLE 3-2. MAJOR TYPES OF MECHANICAL DUST COLLECTORS3
Particle capture
Collector type mechanism(s)
Settling chamber Gravity settling
Elutriator Gravity settling
Momentum separator Gravity settling, inertial
collection
Mechanically aided collector Inertial collection
Centrifugal collector (cyclone) Inertial collection
Reproduced from Table 4.2-1 of Reference 1.
3-3
-------
Large participate can be removed by gravitational settling in settling
chambers to protect downstream equipment from abrasion and excessive mass
loadings. The two basic types are the simple expansion chamber and the
multiple tray settling chamber. The latter is comprised of a set of hori-
zontal collection plates that reduce the distance a particle must fall to
reach the collecting surface. Thus, a multiple tray unit can collect some-
what smaller particles which settle more slowly.
An elutriator consists of a series of one or more vertical tubes or
towers into which a dust-laden gas stream passes at an upward velocity de-
fined by the gas flow rate and the tube cross-sectional area. Large parti-
cles with terminal settling velocities greater than the gas velocity are
separated and collected at the bottom of the chamber. Smaller particles
with a lower settling velocity are carried out of the collector. The par-
ticle size collected may be varied by changing the upward gas velocity.
A momentum separator uses a combination of gravity and particle inertia
(momentum) to settle particles onto collection surfaces. The particles are
separated by providing a sharp change in the direction of gas flow such that
momentum carries the particles across the gas streamlines and into the hop-
per. The simplest versions provide a 90- to 180-degree turn to separate
large particles. Baffles can also be added to increase the number of turns
and thereby provide a modest increase in collection efficiency.
Like that of momentum collectors, the separation mechanism of mechani-
cally aided separators is inertia. Acceleration of the gas stream increases
the effectiveness of inertial separation such that these devices can col-
lect smaller particles than momentum devices. The improved performance is
gained, however, at the expense of higher energy cost and abrasion by the
action of large diameter particles at medium to high velocities.
Finally, the cyclone collector is similar to the momentum separator in
that inertia is used to separate the particles from a turning gas stream.
In a cyclone, a vortex is created within the cylindrical section by either
injecting the gas stream tangentially or by passing the gas stream through a
3-4
-------
set of spin vanes. Due to their inertia, the particles migrate across the
vortex gas streamlines and concentrate near the cyclone walls. Near the
bottom of the cyclone, the gas stream makes a 180-degree turn, and the
particles are discharged either downward or tangentially into hoppers be-
low. The treated gas passes upward and out of the cyclone.
Cyclones can be classified into four basic categories according to the
method(s) used to remove the collected dust and to introduce the gas stream
into the unit. Figure 3-1 illustrates the four basic types of cyclone col-
lectors.1 Cyclones can be used as single collectors or as multiple units
arranged either in parallel, series, or a combination of both.
3.1.2 Electrostatic Precipitators
Electrostatic precipitators (ESPs) are high efficiency particulate
collection devices applicable to a variety of sources and gas conditions.
Particle collection is accomplished by application of electrical energy for
particle charging and collection.
There are two broad categories of ESP: one-stage (or Cottrell-type)
precipitators; and two-stage units. In a single-stage ESP, particle charg-
ing (ionization) and collection are accomplished in a single step, whereas
in two-stage units these functions are accomplished separately. One-stage
ESPs can be further classified according to electrode geometry (e.g., wire-
in- tube versus wire-in-plate type) and type of plate cleaning mechanism
(dry versus irrigated). The dry ESP with wire-in-plate electrodes and
pyramidal hoppers is the predominant type in industrial applications. Two-
stage ESPs are usually limited to air-conditioning applications and the re-
moval of liquid particles in industrial facilities.
Regardless of the type of precipitator and its geometry, the basic
functions of an ESP are to: (1) impart a charge to the particulate;
(2) collect the charged particulate on a surface of opposite polarity;
(3) remove the collected particulate from the collecting surface in a man-
ner that minimizes reentrainment of the particulate into the gas stream;
3-5
-------
TOP VIEW
SIDE VIEW
a. Tangential inlet, axial dust
outlet
TOP
VIEW
b. Tangential inlet, peripheral dust
outlet
TOP VIEW
SIDE VIEW
I I
TOP
VIEW
SIDE
VIEW
^
I
c. Axial inlet, axial dust outlet d.
Axial inlet, peripheral dust dis-
charge
Figure 3-1. General types of cyclones.1
3-6
-------
and (4) discharge the collected participate from the ESP for subsequent
disposal. Each function will be discussed briefly.
To charge the suspended particles, a high-voltage DC current passes
through discharge wires producing an electrical corona. A corona can be
defined as the ionization of gas molecules by electron collisions in re-
gions of high field strength near the discharge wire.2 The strength of the
electric field varies inversely with the distance from the discharge wire.
The corona can be either positive or negative, but negative corona is used
in most industrial precipitators since it has inherently superior electri-
cal characteristics that enhance collection efficiency under most operating
conditions.
Particle charging and subsequent collection take place in the region
between the boundary of the corona glow and the collection electrode, where
gas particles are subject to the generation of negative ions (Figure 3-2).
Charging is generally done by field and diffusion mechanisms. The dominant
charging mechanism varies with particle size.
In general, field charging is most predominant for particles > ~ 0.5
and diffusion charging for particles < ~ 0.2 (jmA.1 The particle size range
of about 0.2 to 0.5 umA is a transitional region in which both mechanisms
of charging are present but neither is dominant. Fractional efficiency
data for precipitators have shown reduced collection efficiency in this
transitional size range, where diffusion and field charging overlap.1
An electric field results from application of high voltage to the dis-
charge electrodes with the strength of this electric field being a critical
factor in determining ESP performance. Space charge effects from charged
particles and gas ions may interfere with generation of the corona and re-
duce the strength of the electric field. The space charge effect is often
seen in the inlet fields of an ESP where particulate concentration is the
highest. From a practical standpoint, the strength or magnitude of the
electric field is an indication of the effectiveness of an ESP.
3-7
-------
FREE
ELECTRONS
REGION OF\
CORONA GLOW\
\
X N.
DUST
PARTICLE
j ELECTRONS
l-e ELECTRON-^
GAS
MOLECULE
CORONA GENERATION
CHARGING
Figure 3-2. Basic processes in electrostatic precipitation.1
3-8
-------
Corona current flows through the collected dust layer to reach the
collection electrode.1 With dry ESPs, high resistivity affects ESP effi-
ciency by limiting current and voltage. If the electrodes are clean, the
voltage can be increased until a sparking condition is reached. The maxi-
mum voltage is determined principally by the gas composition and ESP dimen-
sions. When dust is deposited on the collection electrode however, the
voltage at which sparking occurs is reduced because of the increased elec-
tric field at the dust surface. As dust resistivities increase, the voltage
at which sparking occurs decreases. At resistivity values above approxi-
mately 1012 ohm-cm, the voltage must be reduced so that sparks will not
propagate across the interelectrode space. At very low values of current
and voltage, dust breakdown can occur. This can result in back corona
whereby positive ions form and flow back toward the discharge electrode,
neutralizing the negative charge previously applied and thereby limiting
ESP performance.
To remove the collected particulate from the collection electrodes,
mechanical rappers are used which apply sufficient force to produce a rapid
acceleration perpendicular to the gas flow so that the dust layer shears
off the plate. Sproull indicates that rapping is optimum if the dust layer
slides down the plate vertically after each rap, making its way down the
plate in the discrete steps until it finally reaches the hopper.3
In addition to reducing the performance of an ESP, high resistivity
dust can adhere more strongly to collection electrodes than particles with
intermediate resistivity. Therefore, a much greater rapping acceleration
must be applied to the electrode to remove the dust. This can cause severe
reentrainment or damage to a precipitator that is not designed to withstand
such high acceleration.
With a dust that strongly adheres to the plate, vibrations can be in-
duced perpendicularly to the gas flow, in addition to the necessary shear
action, resulting in a scattering of the agglomerate and subsequent re-
entrainment of relatively large fractions of the dust. In general, the
3-9
-------
dust should be allowed to fall freely off the plate (as sometimes occurs
with high resistivity dust when rapping is done with "power off"). The
other extreme is with low resistivity dust (e.g., < ~ 104 ohm-cm), whose
reentrainment can be caused by only a light rap.
The intensity and frequency of rapping are usually greatest at the in-
let sections, decreasing as the gas moves through the ESP. The outlet sec-
tion is usually rapped only lightly, since the reentrained dust is not re-
collected. The visible puffs that often appear as a result of rapping can
be used to optimize the frequency and intensity of rapping for each section
of the ESP.
Finally, pyramidal hoppers are routinely used for collection and dis-
charging the particulate. Discharge from hoppers may be accomplished by
means of screw, drag, or pneumatic conveying systems. In the pulp and paper
industry, flat bottom, tile-lined precipitators that utilize drag conveyors
are common on recovery boilers. Solids discharge can represent a signifi-
cant problem in the operation of an ESP in that excessive buildup of mate-
rial can cause an electrical shortage or misalignment of ESP internal com-
ponents.
ESP performance as a function of particle size has been measured at
many installations and has been the subject of computer modeling. Probably
the most versatile model is the EPA-Southern Research Institute (SoRI)
Mathematical Model.4 This model can be used for sizing and troubleshooting
ESPs as well as for predicting penetration (1 - collection efficiency). The
reader is referred to the SoRI model for additional assistance in the de-
sign, performance, and evaluation of industrial ESPs.
3.1.3 Fabric Filters (Baghouses)
In its simplest form, the industrial fabric filter (baghouse) consists
of a woven or felted fabric through which dust laden gases are forced. A
combination of factors result in the collection of particles on the fabric
fibers. When woven fabrics are used, a dust cake eventually forms which, in
3-10
-------
turn, provides additional collection sites. When felted fabrics are used,
this dust cake is minimal or nonexistent. Instead, the main filtering
mechanisms are a combination of inertial forces, electrostatic forces, im-
pingement, etc., as related to individual particle collection on single
fiber elements.
As the particulate is collected, pressure drop across the filtering
media increases. Because of fan limitations, the filter must be cleaned.
This cleaning is accomplished "in-place" since the filter area is usually
too large and time between cleanings too short to allow for filter replace-
ment or cleaning external to the baghouse.
Although fabric filters can be classified in a number of ways, the
most common is by method of fabric cleaning. The three major categories
of fabric cleaning methods are: mechanical shaking; reverse air cleaning;
and pulse jet cleaning. Each is described below.
In a conventional shaker-type fabric filter, particulate laden gas en-
ters below the tube sheet and passes from inside the bag to the outside
surface. Particles are captured in a dust cake that gradually builds up as
filtration continues. At regular intervals, a portion of this dust cake
must be removed to enhance gas flow through the filter. The dust cake is
removed (manually on small systems and automatically on larger systems) by
mechanical shaking of the filter fabric which is normally accomplished by a
rapid horizontal motion induced by a shaker bar attached at the top of the
bag. The shaking creates a standing wave in the bag and causes flexing of
the fabric. The flexing causes the dust cake to crack, and portions are
released from the fabric surface. Some of the dust remains on the bag sur-
face and in the interstices of the fabric. Woven fabrics are generally
used in shaker-type collectors with the gas flow stopped before cleaning to
eliminate particle reentrainment and allow dust cake release. Cleaning may
be done by bag, row, section, or compartment.
In reverse air baghouses, particles can be collected in a dust cake
either inside or outside of the bag. Regardless of design differences,
3-11
-------
reverse air cleaning is accomplished by reversal of the gas flow through
the filter media. The change in direction causes the surface contour of
the filter surface to change (relax) and promotes dust cake cracking. The
flow of gas through the fabric assists in removal of the cake. The reverse
flow may be supplied by cleaned exhaust gases or by a secondary fan supply-
ing ambient air.
Finally, on pulse jet fabric filters, particle capture is achieved
partially on a dust cake and partially within the fabric. Filtering is
done on exterior bag surfaces only. During cleaning, a sudden blast of
compressed air is injected into the top of the bag. The blast of air cre-
ates a traveling wave in the fabric, which shatters the cake and throws it
from the surface of the fabric. The cleaning mechanism is classified as
fabric flexing and with some degree of reverse airflow. Felted fabrics are
normally used in pulse jet-cleaned collectors, and the cleaning intensity
(energy) is high. The cleaning normally proceeds by rows, all bags in the
row being cleaned simultaneously. The compressed gas pulse, delivered at
550 to 800 kPa results in local reversal of the gas flow.1 The cleaning
intensity is a function of compressed gas pressure. Pulse jet units can
operate at substantially higher air-to-cloth (A/C) ratios than the types
previously discussed.1 Typical A/C ranges are 1.5 to 3.0 m3/m2-min.1
The two factors of basic importance in fabric filter operation are
particle capture and static pressure loss. Particle capture mechanisms on
a microscopic level are not fully understood. Macroscopic behavior, the
net result of all microscopic processes, indicates that fabric filter col-
lection is not highly size dependent as would be expected in view of the
collection mechanisms. The static pressure loss results from forcing the
gas stream through the fabric and dust cake.
Pore sizes (open areas) of the woven fabric through which the contami-
nated gas stream passes range from 10 to 100 urn, depending on fabric con-
struction and fiber characteristics.1 Initially, the particles easily
penetrate this filter. As filtration continues, some particles are retained
3-12
-------
upon filter elements (normally fibers) because of the combined action of
the classified collection mechanisms shown in Figure 3-3.1 As the dust
cake builds up, additional "targets" are available to collect particles
and penetration drops to very low levels.
Within the dust cake, inertial impaction is the dominant collection
mechanism. The forward motion of the particles results in impaction on
fibers or on already deposited particles.1 Although increasing gas veloc-
ities favor impaction, they reduce the effectiveness of Brownian diffusion
for removal of very small particles. Increasing the fabric porosity also
reduces diffusional deposition.1 As a method of collection, gravity set-
tling of particles is usually assumed to be negligible, although this ef-
fect might be considered at low velocities, however.1
Electrostatic forces can also affect collection. However, the impact
of electrostatic forces in commercial scale equipment is only recently be-
coming understood. Advanced filter designs now incorporate electrostatic
augmentation to achieve high collection efficiencies with reduced pressure
drop across the filter media.5
Dennis and Klemm have presented a computerized model useful for pre-
dicting performance of shaker and reverse air fabric filters. This model
is detailed in References 6, 7, and 8. The reader is directed to these vn «
documents for additional information on baghouse performance. ^J^J$^?^^ ^
3.1.4 Wet Scrubbers
Wet scrubbers comprise a set of control devices with similar particle
collection mechanisms which primarily include inertial impaction and Brownian
diffusion. Accordingly, these scrubber systems generally exhibit strong
particle size-dependent performance. Among scrubber types, substantial dif-
ferences exist with regard to their effectiveness with the greatest differ-
ences occurring in the particle size range of 0.1 to 2
Scrubber liquids are used for particle collection in several distinct
ways. The most common method is to generate droplets, which are then
3-13
-------
DIRECT
INTERCEPTION
DIFFUSION^
INERTIAL
IMPACTI ON
ELECTROSTATIC
ATTRACTION
•— GRAVITATIONAL
SETTLING
Figure 3-3. Initial mechanisms of fabric filtration.1
3-14
-------
intimately mixed with the gas stream. Particles are also collected on water
layers or sheets surrounding of packing material by directing the particle
laden gas stream through an intricate path around the individual packing
elements. A third method is to pass high velocity gas through a vapor to
generate "jets" of liquid to collect particles. This is the least common
of the three liquid characteristics.
In this discussion, major categories of scrubbers are grouped on the
basis of similar mechanisms. The major categories of scrubbers are listed
in Table 3-3 in the order of increasing performance capabilities and energy
requirements. Each type will be briefly described below.
Preformed spray scrubbers require the least energy of the various
scrubbers, and they consequently allow the highest penetration, especially
of small diameter particles. Generally, preformed spray units use one or
more spray nozzles in a countercurrent or cyclonic flow configuration to
remove the incoming particulate by impaction. Most preformed spray scrub-
bers are highly efficient only for particles larger than 5 pmA in diameter.1
In the typical packed bed scrubber, liquid is introduced near the top
and trickles down through the packed bed. The liquid flow spreads over the
packing into a film with a large surface area. The liquid can be introduced
either concurrent or crosscurrent to the gas flow. Packing materials in-
clude raschig rings, pall rings, berl saddles, tellerettes, intalox saddles,
and materials such as crushed rock.1 Packed beds can also be constructed
with metal grids, rods, or fibrous pads. These scrubbers are often used for
gas transfer or gas cooling, both of which are facilitated by the large
liquid surface area provided on the packing.1
Plugging of a packed bed can occur if the gas to be treated is too
heavily laden with solid particles. A general rule for many applications
is to limit the use of packed beds to service in which inlet particulate
concentrations are less than 0.45 g/m3.1 Moving bed scrubbers that have
less plugging potential are packed with low density plastic spheres, which
are free to move within the packing retainers. Packed bed scrubbers are
reported to have low penetration for particle sizes down to 3 umA and
3-15
-------
TABLE 3-3. MAJOR TYPES OF WET SCRUBBERS'
Category
Particle capture Liquid collection
mechanism mechanism
Types of scrubbers
Preformed spray
Packed bed
scrubbers
Tray-type
scrubbers
Mechanically
aided scrubbers
Gas atomized
spray
scrubbers
Inertial
impaction
Droplets
Inertial
impaction
Inertial
impaction
Diffusion
Inertial
interception
Inertial
impaction
Diffusion
Sheets, droplets
(moving bed
scrubbers)
Droplets, jets,
and sheets
Droplets and
sheets
Droplets
Spray towers
Cyclonic spray
towers
Vane-type cyclonic
towers
Multiple tube
cyclones
Standard packed bed
scrubbers
Fiber bed scrubbers
Moving bed scrubbers
Cross flow scrubbers
Grid packed
scrubbers
Perforated plate
Impingement plate
scrubbers
Horizontal impinge-
ment plate
(baffle) scrubbers
Wet fans
Disintegrator
scrubbers
Standard venturi
scrubbers
Variable throat
venturi scrubbers:
flooded disc,
plumb bob, movable
blade, radial
flow, variable rod
Orifice scrubbers
List not intended to be
Reference 1.
all inclusive. Reproduced from Table 4.5-1 of
3-16
-------
can sometimes remove a significant fraction of participate in the range of
1 to 2 umA.l
A tray-type scrubber typically consists of a vertical tower with one
or more perforated plates mounted transversely inside the shell. In such a
scrubber, the liquid and the gas flows countercurrent to one another with
the gases being mixed with the liquid passing through the openings in the
plates. The perforated plates are often equipped with impingement baffles
or bubble caps over the perforations. The gas passing upward through a
perforation is forced to turn 180 degrees into a layer of liquid. The gas
bubbles through the liquid, and particulate is collected in the liquid
sheet. The impingement baffles are below the liquid level on the perforated
plates and are, therefore, continuously washed clean of collected particles.
Penetration through a typical impingement plate is low for particles larger
than 1 umA, but penetration of submicrometer particulate is higher than with
some higher energy scrubbers.1
Mechanically aided scrubbers utilize a mechanical rotor or fan to
shear the scrubbing liquid into dispersed droplets. These scrubbers use a
specially designed stator and rotor arrangement to produce very fine liquid
droplets that are effective in the capture of fine particulate. The low
penetration of fine particulate, however, is achieved at a high energy
cost.1 Because both wet fan and disintegrator-type scrubbers are subject
to particulate buildup or erosion at the rotor blades, they are often pre-
ceded by precleaning devices for removing coarse particulate.1 Mechanically
aided scrubbers generally do not perform well with inlet particulate load-
ings in excess of 1 g/m3.1
Finally, venturi and orifice scrubbers (gas-atomized spray scrubbers)
are perhaps the most common particulate removal devices in that they have
the highest collection efficiency for small particles as compared to most
other types of scrubbers. These scrubbers accomplish fine particulate col-
lection by generating small liquid droplets in the turbulent zone which
creates a high relative velocity between the droplets and the particulate.
Inertia! capture of particulate by the scrubbing liquid is more efficient in
3-17
-------
these highly turbulent processes, but a price is paid in energy consumption
to achieve the low penetration.
Analysis of the particle collection capability of wet scrubbers can be
based on: (a) the fundamental particle collection mechanisms; and (b) the
empirical contact power approach. The latter method is based on the premise
that penetration is proportional to the power expended in the scrubber.1
This premise is logical because high energy consumption implies high rela-
tive gas-water velocities, high water utilization, and fine droplet forma-
tion, all of which favor impaction, the dominant collection mechanism.
Limitations of the contact power analysis can be attributed to the diffi-
culty of handling nonideal operating conditions such as poor gas-liquid
distribution and particle shattering during high energy scrubbing. Also,
this type of analysis is not amenable to situations in which particle col-
lection mechanisms other than inertial impaction are important. Typical
pressure drops for various types of wet scrubbers are shown in Table 3-4.
TABLE 3-4. TYPICAL SCRUBBER PRESSURE DROP3
Pressure drop
Scrubber type (kPa)
Venturi
Centrifugal (cyclonic) spray
Spray tower
Impingement plate
Packed bed
Wet fan
Self- induced spray (orifice)
Irrigated filter (filter bed
scrubber)
1.5 -
0.25 -
0.25 -
0.25 -
0.25 -
1.0 -
0.5 -
0.05 -
18.0
0.8
0.5
2.0
2.0
2.0
4.0
0.8
a Reproduced from Table 4.5-3 of Reference 1.
3-18
-------
Penetration analyses based on the fundamental particle collection
mechanisms involve the identification of the dominant physical phenomenon
leading to particle capture. The following is a partial list of the col-
lection mechanisms:
Collection Medium
Droplets
Liquid sheets (layers)
Liquid sheets
Bubbles
Capture Phenomenon
Inertia! impaction
Interception
Brownian diffusion
Inertial impaction
Interception
Brownian diffusion
Electrostatic attraction
Inertial impaction
Interception
Diffusion
Inertial impaction
Interception
Brownian diffusion
Electrostatic attraction
For each control device, penetration relationships are based on anticipated
particle collection mechanisms. The accuracy of the resulting equations
depend on the proper assignment of the mechanisms and on the accuracy of
the theoretical expressions. Penetration expressions are presented in the
Scrubber Handbook (and subsequent documents) for selected types of wet
scrubbers.9'10 The reader is referred to this information for a detailed
discussion of such expressions and their theoretical development.
3.1.5 Performance Data for Gas Cleaning Equipment
Limited control efficiency data for PMio are available in the EPA Con-
trol Techniques document (Reference 1) for various types of industrial gas
cleaning equipment. Typical control efficiency values contained in Ref-
erence 1 have been summarized in Tables 3-5, 3-6, and 3-7 for mechanical
dust collectors, ESPs/fabric filters, and wet scrubbers, respectively.
3-19
-------
CO
ro
TABLE 3-5. TYPICAL PM10 CONTROL EFFICIENCIES FOR MECHANICAL
DUST COLLECTORS3
Type of process
Sinter plant
Coal -fired boiler
Type of
particulate
Quartz
Iron oxide
Fly ash
Fly ash
Type of collector
Settling chamber
Momentum separator
(grit arrestor)
Momentum separator
Collector design/
operating parameters
Height = 3.05 m
Width = 3.05 m
Volume = 950 m3
Gravity settling of
collected dust
Cyclones used for
PMio control
efficiency (%)
0
0
8.6
12
Not specified^
Wood-fired boiler
? p = 2 g/cm3
Wood fly ash
Wood fly ash
(grit arrestor)
Simple scroll
collector
Buell-van Tongeren
scroll collector
with cyclone dust
separation
Large-diameter
cyclone
Multiclone
collected dust
separation
Collector diameter =
2.1 m
Airflow = 396 mVmin
Unspecified
Unspecified
Unspecified
4.3
39
23
50
Data taken from pages 4.2-16, 4.2-17, 4.2-19, and 9.2-38 of Reference 1. All values approximate.
Size-efficiency curve obtained from original reference, f
-------
TABLE 3-6. TYPICAL PM10 CONTROL EFFICIENCIES FOR ELECTROSTATIC PRECIPITATORS
AND FABRIC FILTERS8
CJ
I
ro
Type of process
Type of Collector design/ . PMio control
particulate Type of collector operating parameters efficiency (%)
Pulverized coal-fired
boiler
Pulverized coal-fired
boiler
Wet process cement
kiln
Sinter machine windbox6
Copper reverb, furnace
Pulverized coal -fired
boiler
Fly ash
Fly ash
Clinker
(BasicidicT^)
stnter
Metallurgical
fume
Fly ash
Unspecified ESP
Unspecified ESP
Hot- side ESP
Dry ESP
Unspecified ESP
Reverse-air fabric
filter
SCA = 147 m2/m3/sec 99. 6f^ ***
SCA^= 60 mVmVmin 96.3
*=- <^^4>4~^/
-------
TABLE 3-7. TYPICAL PM10 CONTROL EFFICIENCIES FOR WET SCRUBBERS'
ro
ro
Type of process
Pulverized coal-fired
boiler
Borax-fusing
furnace
Potash dryer
Salt dryer
Coke oven
Gray iron cupola
Type of
parti cul ate
Fly ash
Fly ash
Borax
crystals
Potash
KC1
Coke/
volatiles
Dust/fume
Type of collector
Venturi scrubber
/^ s_
* f4*—&rt~}t_,fLri,:
(^C^vari able- throat
venturi scrubber
Venturi scrubber
Multivane scrubber
Wetted fiber
scrubber
Venturi scrubber
Venturi rod
scrubber
Collector design/ .
operating parameters
Ap = 2.5 kPa
Ap = 4.2 kPa
Ap = 11 kPa (design)
Ap = 0.78 kPa
Unspecified
Ap = 15 kPa
Ap = 10-23 kPa
PMio control
efficiency (%)
85.2
97.3
96.5
59.2
87.8
96
98
a Data taken from pages 9.2-9, 9.5-28, 9.5-47, 9.8-27, and 9.8-95 of Reference 1.
Ap = pressure drop across the scrubber.
c Furnace operating at 50-75% of rated capacity. Chemical composition of borax is Na2B407
Pushing operation equipped with a traveling hood system.
10H20.
-------
The control efficiencies reported in the above tables were taken either
from available size-efficiency curves or from tabulated data. Approximate
values have been indicated wherever size-efficiency curves were used to cal-
culate the applicable control efficiency (area under the curve) for a par-
ticular system. Also, those curves not representing actual test data were
deleted from Tables 3-5 through 3-7, as appropriate. If more detailed in-
formation is desired to conduct a specific analysis, the reader is directed
to the original reference document indicated on the page in Reference I
noted as footnote (a) of each table.
j> In addition to Reference 1, the documents listed in Table 3-1 can also
//)/ be used as resources to obtain PMio control efficiency data for gas clean-
7 if
ing equipment. Another resource is the EPA's Fine Particle Emissions Infor-
mation System (FPEIS) which is part of the Environmental Assessment Data
Systems (EADS) data base.11'12 The FPEIS provides size-specific test data
and process operating parameters for a wide variety of sources and control
equipment.
3.2 CONTROL ALTERNATIVES FOR FUGITIVE EMISSIONS
Besides the reduction of source extent and the incorporation of process
modifications, there are two basic techniques which can be utilized to con-
trol fugitive particulate emissions: prevention of the creation and/or
release of particulate matter into the atmosphere; and capture and removal
of the particles after they have become airborne.13
Selection of suitable control methods depends on the mechanism(s) which
generate the particulate emissions and the specific source involved. The
methods used to control process sources of fugitive particulate emissions
generally take a much different approach from those applied to open dust
sources. Differences in source configuration, process requirements, and
emissions stream characteristics also affect selection of specific controls.
3-23
-------
This section provides information on feasible control techniques for
sources of fugitive particulate emissions and available performance data.
The basic characteristics of each type of control technique are described,
and the types of emission sources amenable to control by the techniques are
discussed. Control techniques applicable to the major sources of fugitive
particulate defined in Section 1 are identified.
The section is divided into four parts. The first two parts describe
preventive and capture/removal control techniques, respectively. The third
part identifies the types of controls applicable to open dust and process
sources. Finally, the fourth part presents available control performance
data taken from Reference 13.
In addition to Reference 13 mentioned above, there are also a number
of other references which contain information on the specific application
and design of fugitive control systems. These references are listed in
Table 3-8. The user is encouraged to consult the documents shown in
Table 3-8 for other pertinent data and information on the various types of
fugitive source controls.
3.2.1 Preventive Measures
Preventive measures include those measures which prevent or substan-
tially reduce the injection of particulate into the surrounding environ-
ment. Preventive measures are independent of whether the particulate is
emitted directly into the ambient air, or into the interior of a building.
The main types of preventive measures include:13
Passive enclosures (full or partial)
Wet suppression
3-24
-------
TABLE 3-8. ADDITIONAL REFERENCE DOCUMENTS FOR
FUGITIVE EMISSION CONTROLS
Kashdan, E. R., et al. Technical Manual: Hood System Capture of Process
Fugitive Emissions. EPA Contract No. 68-02-3953, Research Triangle
Institute, Research Triangle Park, NC, January 1985.
American Conference of Governmental Industrial Hygienists. Industrial
Ventilation, A Manual of Recommended Practice. 18th Edition. Lansing,
MI, 1984.
McDermott, H. J. Handbook of Ventilation for Contaminant Control. Fifth
Printing, Ann Arbor Science Publishers, Inc., Ann Arbor, MI, 1983.
Danielson, J. A. Air Pollution Engineering Manual. AP-40. U.S. Environ-
mental Protection Agency, Research Triangle Park, NC, May 1973.
Hemeon, W. C. L. Plant and Process Ventilation. The Industrial Press,
New York, NY, 1963.
Ohio Environmental Protection Agency. Reasonably Available Control Mea-
sures for Fugitive Dust Sources. Columbus, OH, September 1980.
Mukherjee, S. K., and M. M. Singh. Design Guidelines for Improved Water
Spray Systems - A Manual. Contract No. J0308017, U.S. Bureau of
Mines, Washington, DC, December 1981.
3-25
-------
Stabilization of unpaved surfaces
Paved surface cleaning
*7 * C.£A?"B|i7\^ S^e^ti fJdtffeA ffc^S
i * J
Work practices
Housekeeping
Descriptions of control techniques within these five categories are pre-
sented below.
3.2.1.1 Passive Enclosures—
A common preventive technique for the control of fugitive particulate
emissions is to either fully or partially enclose the source. Enclosures
preclude or inhibit particulate matter from becoming airborne due to the
disturbance created by ambient winds or by mechanical entrainment resulting
from the operation of the source itself. Enclosures also help contain those
emissions which are generated. Enclosures can consist of either some type
of permanent structure or a temporary arrangement. The particular type of
enclosure used is dependent on the individual source characteristics and
the degree of control required.
Permanent enclosures are designed to either partially or completely
enclose the source by the construction of a building or other structure.
Worker safety and housekeeping can become problems in the vicinity of the
fugitive emission source controlled by a passive (nonevacuated) enclosure.
Types of sources commonly controlled by total enclosures include aggregate
storage (bins rather than piles) and external conveyor transport.
Since temporary enclosures take many forms, they are difficult to
classify generically. Examples of temporary enclosures are flexible
tarpaulin covers over the hatchways of large ocean-going vessels during the
loading of grain, or flexible shrouds around truck loading spouts.
3-26
-------
A novel variation to the source enclosure method for the control of
fugitive particulate emissions involves the application of porous wind
fences. Porous wind fences have been shown to significantly reduce emis-
sions from active storage piles and exposed ground areas.13 The principle
employed by wind screens is to provide a sheltered region behind the fence-
line which significantly reduces the mechanical turbulence generated by
ambient winds in an area the length of which is many times the physical
height of the fence. This sheltered region provides for both a reduction
in the wind erosion potential of the exposed surface in addition to allow-
ing the gravitational settling of larger particles. The application of wind
screens along the leading edge of active storage piles seems to be one of
the few good control options which are available for this particular source.
A diagram of one type of portable wind screen used at a coal-fired power
plant is shown in Figure 3-4.14
3.2.1.2 Wet Suppression--
Wet suppression systems apply either water, a water solution of a
chemical agent, Or a micron-sized foam to the surface of the particulate
generating material.13 This measure prevents or suppresses the fine parti-
cles contained in that material from leaving the surface and becoming air-
borne. If fine water sprays are used to control dust after it has become
suspended, this is referred to as plume aftertreatment. Plume aftertreat-
ment (e.g., charged fog) is not a preventive measure but a capture/removal
method as discussed below.
The chemical agents used in wet suppression systems can be either sur-
factants or foaming agents for materials handling and processing operations
(e.g., crushers, conveyors) or various types of dust palliatives applied to
unpaved roads. In either case, the chemical agent acts to agglomerate and
bind the fines to the aggregate surface, thus eliminating or reducing its
emissions potential. Each major type of wet suppression method will be
described individually.
3-27
-------
u>
rv>
CO
Gate Hinges, U-bolt attach
to both 1.90" O.O. fence
panel and 6.623" O.D. runners
Runners filled with scrap steel so that the
pallet (less fence panels and back supports)
weighs 6,000 pounds with the e.g. midway
between the runner
Fence Panel Frames
1-7/4" (1.90" O.D.)
Supports
2-1/2" Nom. (2.875" O.D.)
Bracket Required
Runners
6" Nom. (6.625" O.D.)
Shear Braces
2-1/2 Nom (2.875" O.D.)
Figure 3-4. Diagram of a portable wind screen.14
-------
Wet suppression systems using plain water have been utilized for many
years on a variety of sources such as crushing, screening, and materials
transfer operations, as well as unpaved roads. For most mechanical equip-
ment, wet suppression involves the use of one or more water sprays to wet
the material prior to processing. This technique is usually only temporar-
ily effective, requiring repeated application throughout the process flow.
It should be noted that, in addition to possible freezing problems in
the winter, wet suppression with plain water can be used only on those bulk
materials which can tolerate a relatively high surface moisture content.
In the arid West, wet suppression is not always practical due to inadequate
water supplies.
In the case of unpaved roads and parking lots, water is generally ap-
plied to the surface by a truck or some other type of vehicle utilizing
either a pressurized or a gravity flow system. Again, watering of unpaved
roads is only a temporary measure, necessitating repeated application at
regular intervals.
To improve the overall control efficiency of wet dust suppression sys-
tems, wetting agents can be added to the water to reduce the surface ten-
sion. The additives allow particles to more easily penetrate the water
droplet and increase the number of droplets, thus increasing the surface
area and contact potential.
One of the more recently developed methods used to augment wet suppres-
sion techniques is the use of foam to control dust from materials handling
and processing operations. The foam is generated by adding a proprietary
surfactant compound to a relatively small quantity of water which is then
vigorously mixed to produce a small bubble, high energy foam in the 100-
to 200-um size range.13 The foam uses very little liquid volume and,
when applied to the surface of a bulk material, wets the fines more effec-
tively than does untreated water. Foam has been used with good success for
3-29
-------
controlling the emissions from belt transfer points, crushers, and storage
pile load-in.
3.2.1.3 Stabilization of Unpaved Surfaces--
Release of particulate from unpaved surfaces can be reduced or pre-
vented by stabilization of those surfaces. Sources which have been con-
trolled in this manner include unpaved roads and parking lots, active and
inactive storage piles, and open areas. Stabilizing mechanisms which have
successfully employed include chemical, physical, and vegetative controls.
Each of these control types is described below.
The use of chemical dust suppressants for the control of fugitive emis-
sions from unpaved roads has received much attention in the past several
years. Chemical suppressants can be classified into six generic categories.
These are: (1) salts (i.e., CaCl2 and MgCl2); (2) lignin sulfonate; (3) wet-
ting agents; (4) latexes; (5) plastics; and (6) petroleum derivatives.13
Chemical dust suppressants are generally applied to the road surface
as a water solution of the agent. The degree of control achieved is a di-
rect function of the application intensity (volume of solution/area), dilu-
tion ratio, and frequency (number of applications/unit time) of the chemical
applied to the surface and also depends on the type and number of vehicles
using the road. Chemical agents have also been proven to be effective as
crusting agents for inactive storage piles and for the stabilization of ex-
posed open areas and agricultural fields. In both cases, the chemical acts
as a binder to reduce the wind erosion potential of the aggregate surface.
Physical stabilization techniques can also be used for the control of
fugitive emissions from unpaved surfaces. Physical stabilization includes
any measure, such as compaction of fill material at construction and land
disposal sites, which physically reduces the emissions potential of a source
resulting from either mechanical disturbance or wind erosion.
3-30
-------
The most notable form of physical stabilization of current interest
involves the use of civil engineering fabrics or "road carpet" for unpaved
roads.13 In practice, the road carpet fabric is laid on top of a properly
prepared road base just below a layer of coarse aggregate (ballast). The
fabric sets up a physical barrier such that the fines (< 74 urn in diameter)
are prevented from contaminating the ballast layer. These smaller particles
are now no longer available for resuspension and saltation resulting from
the separation of the fines from the ballast. The fabric is also effective
in distributing the concentrated stress from heavy-wheeled traffic over a
wider area.
Vegetative stabilization involves the use of various plant species
to control wind erosion from exposed surfaces. Vegetative techniques can
be used only when the material to be stabilized is inactive and will remain
so for an extended period of time. It is often difficult to establish a
vegetative cover over materials other than soil because their physical or
chemical characteristics are not conducive to plant growth. Resistant
strains which can tolerate the composition of the host material sometimes
must be developed.
3.2.1.4 Paved Surface Cleaning--
Other than housekeeping, the only method available to reduce the sur-
face loading of fine particles on paved roads is through some form of
street cleaning practice. Street sweeping does remove some debris from
the pavement thus preventing it from becoming airborne by the action of
passing vehicles; but it can also generate significant amounts of finer
particulate by the mechanical action used to collect the material.13
The three major methods of street cleaning are mechanical cleaning;
vacuum cleaning; and flushing.13 Mechanical street sweepers utilize large
rotating brooms to lift the material from the pavement and discharge it
into a hopper for later disposal. Broom sweepers are usually effective in
picking up only relatively large debris, with a significant portion of the
3-31
-------
surface material being suspended in the wake of the vehicle (as observed in
the field.
Vacuum sweepers remove the material from the street surface by drawing
a suction on a pickup head which entrains the particles in the moving air
stream. The debris is then deposited in a hopper, and the air is exhausted
to the atmosphere. Vacuum units also use gutter brooms to loosen and de-
flect debris so that it can be picked up. They also have an additional
broom which loosens the street dirt and pushes it toward the vacuum nozzles
where it is drawn into the storage compartment. A filter system traps the
dust and confines it to the sweeper hopper.
The regenerative sweeper is a vacuum unit with certain significant
differences. Cleaning is accomplished by a pickup head with rubber dust
curtains at the front. The sweeper usually has a 2.7-m (9-ft) cleaning
width.13 A blower directs a strong blast of air across the pickup head,
and the suction from the blower draws the debris into the hopper through a
dust separator. Thus, the air circulates continuously through the vacuum
sweeper mechanism with no air and little dust exhausted to the atmosphere.
Street flushers hydraulically remove debris from the surface to the
gutter and eventually to the storm sewer system through the use of high
pressure water sprays. Water storage tanks on flushers vary in capacity
from 3,030 to 13,250 L (800 to 3,500 gal.).13 Flushers have large nozzles,
individually controlled, which can be directed either toward the gutter or
in a forward direction. Water emerges from the nozzles at pressures of up
to 690 kPa (100 psig).13 This pressure is usually sufficient to scour most
debris on the pavement. Flushers have numerous operational disadvantages
including the consumption of large quantities of water with the associated
potential for water pollution problems. A diagram of both a typical broom
sweeper and a regenerative air sweeper is shown in Figure 3-5.15
3-32
-------
ELEVATOR
HOPPER
PICKUP BROOM-,
•GUTTER BROOM
(a) Four-wheeled broom sweeper
HOPPER
AUXILIARY ENGINE
PICKUP HEAD GUTTER BROOM
(b) Regenerative air vacuum sweeper
Figure 3-5. Diagrams of typical street cleaners.15
3-33
-------
3.2.1.5 Housekeeping-
Housekeeping generally refers to the removal of exposed dust producing
materials on a periodic basis to reduce the potential for dust generation
through the action of wind or machinery. Examples of housekeeping measures
include: clean-up of spillage on travel surfaces (paved and unpaved); elim-
ination of mud/dirt carryout onto paved roads at construction and demolition
sites; and clean-up of material spillage at conveyor transfer points.13
Any such method can be employed depending on the source, its operation,
and the type of dust-producing material involved. A detailed evaluation is
necessary on a case-by-case basis to determine what housekeeping measures
can be employed.
3.2.2 Capture Removal Methods
The second basic technique for the control of fugitive particulate
emissions includes those methods which capture or remove the particles af-
ter they have become airborne. Again, this classification is irrespective
of whether such emissions are generated inside or outside of a building.
The major types of capture/removal processes include:
Capture and collection systems
Plume aftertreatment
The various methods in both categories are described below.
3.2.2.1 Capture and Collection Systems--
Most industrial process fugitive emissions have traditionally been con-
trolled by capture/collection, or industrial ventilation systems. These
systems have three primary components: (1) a hood or enclosure to capture
emissions that escape from the process; (2) a dust collector that separates
entrained particulate from the captured gas stream (see Section 3.1 above);
3-34
-------
and (3) a ducting or ventilation system to transport the gas stream from the
hood or enclosure to the air pollution control device.
A wide variety of capture methods ranging from total enclosure of the
source, to mobile high velocity low volume (HVLV) hoods, to total building
evacuation have been employed. Capture devices (or hoods) generally can be
classified as one of three types: enclosure, capture hood, or receiving
hood. Each type is illustrated in Figure 3-6.16
Enclosures, partial or complete, surround the source as much as possi-
ble without interfering with process operations. Their predominant feature
is that they prevent release of particulate to the atmosphere or working
environment. The enclosure is equipped with one or more takeoff ducts to
remove particulate that is generated and to maintain a slight negative
pressure in the enclosure. Examples of enclosures include enclosed shake-
out operations in metal foundries, casings on bucket elevators used for
aggregate material transfer, and building evacuation for secondary furnace
control.
Capture hoods are located in such a manner that the process is external
to the hood. Emissions are actually released to the atmosphere or plant
environment and subsequently captured by the hood. Capture hoods have also
been referred to as exterior hoods by some authors.13
The operating principle of the capture hood is based on capture veloc-
ity. The control system must produce a sufficient air velocity at the
source to draw the emitted particles to the hood and "capture" the emissions
stream. Examples of capture devices are side-draft hoods to capture secon-
dary electric arc furnace emissions, push/pull side-draft hoods to control
metal pouring emissions, and side-draft hoods to control cleaning and fin-
ishing emissions.
3-35
-------
Fan
(a) Enclosures - contain
contaminants released
Inside the hood
Contaminants
rising from
hot process
(b) Receiving hoods - catch
contaminants that rise or
are thrown into them
(c) Capturing hoods - reach
out to draw in contami-
nants
Figure 3-6. General types of capture devices (hoods).16
3-36
-------
In the case of receiving hoods, emissions from the process are also
released to the plant environment or atmosphere prior to entering the hood.
However, receiving hoods are designed to take advantage of the inherent
momentum of some emissions streams. This momentum is generally a result of
thermal buoyancy but also may be a result of inertia generated by the pro-
cess (e.g., a grinding plume). The system does not need to generate a
capture velocity, but it should be designed to exhaust a slightly greater
velocity from the hood than the process delivers. Examples of receiving
hoods include canopy hoods to capture secondary furnace emissions, close
capture hoods located above metal pouring operations, and grinding wheel
close capture hoods.
The selection of a suitable capture device is site-specific and depends
on both the operating and emissions characteristics of the source. Factors
influencing selection include location of the process with respect to other
plant operations, degree of process movement (if any), space needed for
worker or equipment access to the process, physical size of the operation
or process, and momentum of the particulate plume due to buoyancy or inertia
applied by the process.
Particulate matter is removed from the gas stream in capture/collection
systems by one of four generic types of air pollution control devices: me-
chanical collectors (or cyclones), wet scrubbers, fabric filters, and elec-
trostatic precipitators (ESPs). As with the capture device, selection of
the air pollution control device is site-specific, depending on such factors
as: degree of control required to meet regulations or enhance product re-
covery; availability of excess capacity from an existing control device;
feasibility of designing a common device for multiple sources; and various
characteristics of the emissions stream. Some of the more important emis-
sions characteristics are particle size distribution, particle resistivity,
gas temperature, corrosivity, and chemical composition.
3-37
-------
The simplest, and most often neglected, component of the industrial
ventilation system is the ductwork or transport system. The transport sys-
tem must be designed to maintain adequate transport velocities in the ducts
and be balanced with respect to pressure drop. Two of the most common
causes of malfunctions of capture/collection systems are plugging of the
ductwork because of inadequate transport velocities and unbalanced ventila-
tion systems (from either poor design or improper operation) resulting in
inadequate capture velocities or exhaust volumes at some processes.13
A variation of the traditional capture/collection concept involves the
use of air curtains or jets. Air curtains are usually used in those indus-
trial processes which generate a buoyant plume to help isolate it and en-
hance capture by the emissions control system. One such system is a so-
called "push/pull" arrangement. In such an arrangement, an air curtain
consisting of a series of jets is used to contain and direct the plume to-
ward some type of capture device. One such system is shown in Figure 3-7
for a copper converter.17
3.2.2.2 Plume Aftertreatment--
Plume aftertreatment refers to any system which injects fine water
droplets into a dust plume to capture and agglomerate the suspended parti-
cles (by impaction and/or electrostatic attraction) to enhance gravitational
settling. Plume aftertreatment systems can use water sprays with or without
the addition of a chemical surfactant as well as with or without the appli-
cation of an electrostatic charge (charged fog).
Aftertreatment systems using plain v/ater consist of one or more hydrau-
lic (pressure) or pneumatic (two-fluid) nozzles which create a spray of fine
water droplets. When sprayed into the dust plume, these droplets capture
and settle the suspended dust particles. This technique has been used ex-
tensively for the control of respirable dust in underground mining and simi-
lar operations conducted above ground.13
3-38
-------
FROM AIR JET FAN
CO
i
oo
UD
PRIMARY
HOOD
LOCATION
o
JET SIDE
AIR
CURTAIN
JET
-TO EXHAUST FAN
BAFFLE WALL-
SEAL
EXHAUST SIDE
CUH
/ t f
^TT
*
CONVERTER /
(FUME SOURCE)
V /
TO EXHAUST FAN
BAFFLE WALL
Figure 3-7. Converter air curtain control system.17
-------
In the past several years, a novel means has been developed to augment
traditional water sprays for plume aftertreatment involving the use of
electrostatics. Most anthropogenically produced particles normally acquire
a slight electrostatic charge.13 By injecting a fog of oppositely charged
water droplets into the plume, a significant enhancement in the capture and
removal process can be achieved.13
An electrostatic charge is generally applied to a water spray by either
of two means. Induction charging applies an electrostatic charge to the
droplets by passing the spray through a ring which is isolated at a high
voltage. The alternative is to charge the water prior to atomization by
direct contact. Of the two methods, contact charging has proven to be much
more effective in achieving a higher charge-to-mass ratio. Under heavy
spray conditions, induction charging tends to apply a charge only those
droplets on the outside of the spray cone. Diagrams of electrostatic fog-
gers using both induction and contact charging are shown in Figure 3-8.18
3.2.3 Applicability of Controls to Fugitive Emissions Sources
Process fugitive sources can be controlled by either preventive or
capture/removal measures. Principal control measures include wet suppres-
sion, capture/collection systems, and plume aftertreatment. Table 3-9
identifies the types of control'applicable to process fugitive emissions
sources.13
Open dust sources are generally controlled by preventive techniques
rather than capture/removal techniques. Typical measures used include pas-
sive enclosures, wet suppression, stabilization, and surface cleaning.
Table 3-10 identifies the types of control measures applicable to each of
the generic open dust source categories identified in Section I.13
3-40
-------
POLARITY
LIGHTS
AIR PURGE
VALVE
INDUCTION
RING
SPRAY
NOZZLE
AIR AND FLUID CAPS
(a) Electrostatic fogger using induction charging
Air Fan
Nonconduct'i v«
Air cone
Water Deflecting
Baffle
Monconductive
Spinning Cup
Rotating
Seal
DC Power
Supply
Isolated
Water
Supply
(b) Electrostatic fogger using contact charging
Figure 3-8. Electrostatic foggers.18
3-41
-------
TABLE 3-9. PROCESS FUGITIVE PARTICIPATE EMISSION SOURCES AND FEASIBLE CONTROL TECHNOLOGY3
CJ
i
-p.
ro
Control measure
Capture/collection
Industry
Iron and Steel Plants
Ferrous Foundries
Primary Aluminum Production
Primary Copper Smelters
Primary Copper Smelters
Wet .
Process source suppression
Coal Crushing/Screening X
Coke Ovens
Coke Oven Pushing
Sinter Machine Windbox X
Sinter Machine Discharge
Sinter Cooler
Blast Furnace Charging
Blast Furnace Tapping
Slag Crushing/Screening X
Molten Iron Transfer
BOF Charging/Tapping/Leaks
Open Hearth Charging/Tapping/Leaks
EAF Charging/Tapping/Leaks
Ingot Pouring
Continuous Casting
Scarfing
Furnace Charging/Tapping
Ductile Iron Inoculation
Pouring of Molten Metal
Casting Shakeout
Cooling/Cleaning/Finishing of Castings
Core Sand and Binder Mixing
Core Baking
Grinding/Screening/Mixing/
Paste Production
Anode Baking
Electrolytic Reduction Cell
Refining and Casting
Roaster Charging
Roaster Leaks
Furnace Charging/Tapping/
Leaks
Stag Tapping/Handling
Converter Charging/Leaks
Blister Copper Tapping/Transfer
Copper Tapping/Casting
Enclosures0
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Receiving
hoods
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Capture Plume after-
hoods treatment
X X
X
X
X X
X
X
X
X
X
(continued)
-------
TABLE 3-9. (continued)
CO
i
CO
Control measure
Industry
Primary Lead Smelters
Primary Zinc Production
Secondary Aluminum Smelters
Secondary Lead Smelters
Secondary Zinc Production
Process source
Raw Material Mixing/Pelletizing
Sinter Machine Leaks
Sinter Return Handling
Sinter Machine Discharge/Screens
Sinter Crushing
Blast Furnace Charging/Tapping
Lead and Slag Pouring
Slag Cooling
Slag Granulator
Zinc Fuming Furnace Vents
Dross Kettle
Silver Retort Building
Lead Casting
Sinter Machine Windbox Discharge
Sinter Machine Discharge/Screens
Coke-Sinter Mixer
Furnace Tapping
Zinc Casting
Sweating Furnace
Smelting Furnace Charging/Tapping
Fluxing
Dross Handling and Cooling
Scrap Burning
Sweating Furnace Charging/Tapping
Reverb Furnace Charging/Tapping
Blast Furnace Charging/Tapping
Pot Furnace Charging/Tapping
Tapping of Holding Pot
Casting
Sweating Furnace Charging/Tapping
Hot Metal Transfer
Melting Furnace Charging/Tapping
Distillation Retort Charging/Tapping
Distillation Furnace Charging/Tapping
Casting
Wet .
suppression Enclosures
X
X
X
X
X
X
X X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Capture/collection
Receiving Capture Plume after-
hoods hoods treatment
X
X
X
X
X X
X
X
X
X
X
X
X
X
X
X
X
X
X X
X
X
X
X
X
X
X
X
X
X
X
X
(continued)
-------
TABLE 3-9. (concluded)
to
Control measure
Capture/col lection
Industry
Secondary Copper, Brass/
Bronze Production
Ferroalloy Production
Cement Manufacturing
Lime Manufacturing
Rock Products
Asphalt Concrete Plants
Coal-Fired Power Plants
Grain Storage and Processing
Wood Products
Mining
Process source
Sweating Furnace Charging/Tapping
Dryer Charging/Tapping
Melting Furnace Charging
Casting
Raw Materials Crushing/
Screening
Furnace Charging
Furnace Tapping
Casting
Limestone/Gypsum Crushing and
Screening
Coal Grinding
Limestone Crushing/Screening
Lime Screening/Conveying
Primary Crushing/Screening
Secondary Crushing/Screening
Tertiary Crushing Screening
Aggregate Crushing/Screening
Coal Pulverizing/Screening
Grain Cleaning
Grain Drying
Log Debarking/Sawing
Veneer Drying
Plywood Cutting
Plywood Sanding
Blasting
Crushing/Screening
Wet .
suppression Enclosures
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Receiving
hoods
X
X
X
X
X
X
X
X
Capture
hoods
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Plume after-
treatment
X
X
X
X
X
X
X
X
X
X
X
X
X
a From Table 4-2 of Reference 13.
Water or water plus chemical additives.
Includes full and/or partial enclosures with possible evacuation
d M
. .
to a dust
collector.
-------
TABLE 3-10. FEASIBLE CONTROL MEASURES FOR OPEN OUST SOURCES3
U>
I
Source category
Unpaved roads
Unpaved parking lots and staging areas
Storage piles
Paved streets and highways
Paved parking lots and staging areas
Exposed areas
Batch drop operations
Continuous drop operations6
Pushing (e.g., dozing, grading,
scraping, etc. )
b Wet
Enclosures suppression
X
X
X X
X X
X X
X X
X
Fugitive emission control measure
Chemical Physical Vegetative
stabilization stabilization stabilization
X X
X X
X X
XXX
X
Surface Capture/
cleaning removal
X
X
X
X
From Table 4-1 of Reference 13.
Includes full and partial enclosures as well as wind fences.
c Includes both capture/collection systems and plume aftertreatment.
Includes operations such as front-end loaders, shovels, etc.
Includes operations such as conveyor transfer, stacking/reclaiming, etc.
-------
3.2.4 Performance Data for Process Fugitive Controls
Essentially all of the control techniques used to abate the fugitive
emissions associated with process sources utilize traditional engineering
approaches.13 Although performance data are sparse, the application of
this technology is generally well developed (with the possible exception of
plume aftertreatment). Such is not usually the case for open source con-
trols, as will be discussed below.
Available PMio control efficiency data for water/foam suppression,
capture/collection systems, and plume aftertreatment are presented in
Tables 3-11, 3-12, and 3-13, respectively.13 All data shown in these ta-
bles were taken directly from Reference 13. Additional information on how
the various values were obtained can be found in that document. As shown
by these tables, very limited data currently exist on PMio control effi-
ciency for control techniques applicable to process fugitive sources.
It should also be noted that a major portion of the control efficiency
data presented in Tables 3-11 to 3-13 have been expressed in terms of respir-
able dust instead of PMio. Respirable dust is defined as that particulate
which passes through a Dorr Oliver 10-mm nylon cyclone attached to a per-
sonal sampler operating at a flow rate of 1.7 L/min. The cyclone precol-
lector has a cutpoint which is approximately 10 umA, although it is not
usually expressed as such. Therefore, the control efficiency for respirable
dust should closely approximate that for PMxo for the source/control com-
binations listed.
3.2.5 Performance Data for Open Dust Controls
Control techniques applied to open dust sources generally are less
durable than traditional control devices applied to ducted sources. It is
common practice to assign a single control efficiency value to a baghouse,
cyclone, or scrubber. Ducted source controls are generally attributed the
capability to maintain a set control efficiency value for extended periods
(e.g., 1 or 2 years) given proper maintenance and operation.
3-46
-------
TABLE 3-11. SUMMARY OF AVAILABLE PM10 CONTROL EFFICIENCY DATA FOR WATER SPRAYS AND FOAM SUPPRESSION
(PROCESS SOURCES)3
Type of
process
Type of
material
Process
design/
operating
parameters
Control system
parameters
PMjo
control
efficiency
Comments
Crusher
OJ
I
Secondary
crusher
Gypsum
Limestone
Tertiary Limestone
crusher
Not specified
424 tons/hr,
3 in. mate-
rial size
127 tons/hr,
5/8 in.
nominal ma-
terial size
3 Nozzles (2 x 1/32
in. flat), 200
parts H20/l part
foaming agent
Water spray - not
specified
Water spray - not
specified
27%L
92%
83%
Efficiency based on
concentration only
No calibration or wind
data available
Reproduced from Table 6-1 of Reference 13. 1 ton = 0.91 Mg; 2.54 cm = 1 in.
Control efficiency for respirable dust which is approximately the same as PMxo.
-------
TABLE 3-12. SUMMARY OF PM10 CONTROL EFFICIENCY DATA FOR CAPTURE/COLLECTION SYSTEMS (PROCESS SOURCES)'
CO
I
-pi
CO
Capture
Process mechanism/
design/ air pollution
Type of Type of operating control
process material parameters device
Aluminum Molten Not specified Close cap-
reduction aluminum ture hood/
cell-anode NA
Aluminum Molten Not specified Close cap-
reduction aluminum ture/NA
cell tap-
ping
Anode Molten Not specified Close cap-
removal aluminum ture/NA
Banbury NA Not specified Capture
mixer hood/NA
» /J^
0 ' &3sr^$S:^L
II':&
-------
.<> ft-
0
TABLE 3-13. SUMMARY OF AVAILABLE CONTROL PM10 EFFICIENCY DATA FOR
PLUME AFTERTREATMENT SYSTEMS (PROCESS SOURCES)3
Type of process
Type of
material
Process design/
operating
parameters
Average
. control
Fogger system efficiency
Bag splitting
hood
Cream-tex:
32% alumina
52% SiO,
Not specified
2-Ransburg REA foggers
located inside hood;
WFR = 45 cc/min total
AF = 4.3 mVhr total
45-61%
Includes only results of field testing. Reproduced from Table 6-4 of Reference 13.
The Ransburg foggers are based on the original Hoenig design which uses induction
charging and commercial spray nozzles. WFR = water flow rate. AF = airflow to
fogger(s).
Control efficiency for respirable dust which is approximately the same as
Efficiency ranges include average efficiency for both positively/negatively charged
fog.
In contrast to ducted source controls, intermittent control techniques
which begin to decay in efficiency almost immediately after implementation
are often used for open dust sources. The most extreme example of this is
the watering of unpaved roads where the efficiency decays from nearly 100%
to zero in a matter of hours (or minutes). The control efficiency for broom
sweeping and flushing applied in combination on a paved road may decay to
zero in 1 or 2 days. Chemical dust suppressants applied to unpaved roads
can yield control efficiencies that will decay to zero in several months.
Consequently, a single-valued control efficiency is usually not adequate to
describe the performance of most intermittent control techniques for open
dust sources. The control efficiency must be reported along with a time
period over which the value applies. For continuous control systems (e.g.,
wet suppression for materials transfer), a single control efficiency is usu-
ally appropriate.
3-49
-------
Certain terminology has been developed to aid in describing the time
dependence of control efficiency for intermittent controls for open dust
sources. These terms are:
Control lifetime is the time period (or amount of source activity)
required for the efficiency of an open dust control measure to
decay to zero.
Instantaneous control efficiency is the efficiency of an open
dust control at a specific point in time.
Average control efficiency is the efficiency of an open dust
source control averaged over a given period of time (or number of
vehicle passes).
From the above definitions, it is clear that average control efficiency
is related to instantaneous control efficiency by the following general
equation:
C(T) = c(t) dv (3-1)
where: C(T) = Average control efficiency during time period T
between applications
c(t) = Instantaneous control efficiency at time t
after application (t ^ T)
Recent testing of certain unpaved and paved road dust controls suggests that
the instantaneous control efficiency can be described with reasonable ac-
curacy as a linear function of vehicle passes (v) as representative of time
in the general form:
c(v) = 100 - b v (3-2)
3-50
-------
where b is the decay rate which is dependent on equipment (e.g., vehicle)
or source characteristics, climatic conditions, and control application
parameters as will be discussed in detail below. By substituting the linear
expression for instantaneous control efficiency into Equation 3-1, the av-
erage control efficiency for V vehicle passes can be expressed as follows:
C(V) = 100 - £ V (3-3)
Typical control techniques employed on open dust sources are listed in
Table 3-14. The specifications necessary to completely define each technique
are also listed. While most of the terminology is familiar, the terms re-
lated to the use of water and chemical dust suppressants need to be defined.
Application intensity is the volume of solution placed on a dust-producing
surface per unit area or per unit mass of aggregate material handled (e.g.,
L/m2, L/Mg). The dilution ratio is defined as volume of chemical mixed with
a given volume of water (e.g., 1 L chemical: 7 L water). Application fre-
quency is the number of applications per unit of time (e.g., 6 applications/
year, 2 applications/week).
Available PM10 control efficiency data for chemical road dust suppres-
sants, unpaved road watering, water sprays, foam suppression systems, and
plume aftertreatment are summarized in Tables 3-15 through 3-19, respec-
tively.13 Again, all data shown in these tables were taken directly from
Reference 13. It should be noted that the control efficiency, values re-
jDorted ijn Tab]e_3-15 .are jaxpjressed as a least-squares .fit of the data based
on the numberjjf vehicle passes over the. road surface. This is consistent
wrth Equation JK3 shown abpve^
3-51
-------
TABLE 3-14. OPEN DUST SOURCE CONTROL TECHNIQUE IDENTIFICATION
Generic source category
Control technique
Technique specifications
I. Vehicular travel on
unpaved surfaces
1. Wet suppression
(watering)
2. Chemical dust
suppressants
Paving
V II. Vehicular travel on
f3 paved surface
1. Vacuum sweeping
2. Flushing
3. Flushing and broom sweep-
ing
1. Application intensity (L/m2)
2. Application frequency
1. Application intensity
2. Application frequency
3. Dilution ratio (L chemical:L H20)
1. Thickness of asphalt or concrete
2. Base preparation techniques
3. Planned maintenance technique speci-
fications to maintain cleanliness (see
technique specifications under paved
faces)
1. Application frequency
2. Sweeper characteristics like:
a. Capacity of blower
b. Air velocity generated along road
surface
c. Type of device used to remove parti-
cles (e.g., bags, water sprays,
scrubbers, settling chambers, etc.)
d. Characteristics of the gutter broom
(e.g., rpm, type of bristle, number
of bristles per unit area)
1. Application frequency
2. Application intensity
1. Application frequency
2. Application intensity
3. Sweeper speed
4. Characteristics of main and gutter
brooms (e.g., rpm, type of bristle,
number of bristles per unit area)
(continued)
-------
TABLE 3-14. (concluded)
Generic source category
Control technique
Technique specifications
III. Material handling
OJ
en
co
1. Enclose transfer stations, 1.
conveyors, material stream 2.
falling onto pile, etc.
2. Spray material on conveyor 1.
with surfactant treated 2.
water
*3.
*4.
Spray material in open 1.
storage with water 2.
Spray material in storage 1.
with chemical dust 2.
suppressant
5. Spray plume with 1.
electrically-charged fog 2.
while material is being 3.
dropped
6. Spray while being dropped 1.
(e.g., railcar, stacker) 2.
7. Reduce drop distance 1.
Full or partial enclosure
Vented or nonvented (full)
enclosure
If vented to control device, give
ventilation rate in acfm.
Amount of solution applied (L/Mg)
Amount of surfactant added to water
(dilution ratio)
No. and type of spray nozzles
Application intensity (L/m2)
Application frequency
Application intensity (L/m2)
Dilution ratio (vol. chem.:vol.
water)
Application frequency
Application intensity (L/Mg)
Charge-to-mass ratio (C/g)
No. of foggers, volume of spray,
and volume of plume
Amount of solution applied (L/Mg)
No. and type of spray nozzles
Exposed drop height before and after
control
These are actually more effective as wind erosion controls rather than material handling controls.
-------
TABLE 3-15. INSTANTANEOUS PM,0 CONTROL EFFICIENCY FOR UNPAVED ROAD CONTROL TECHNIQUES
AS A FUNCTION OF VEHICLE PASSES19
CO
1
en
-p.
Control measure
Petro Tac-Initial
application
Coherex® - initial
application
Coherex® -
reapplication
Watering
Average
No. of Mean
vehicle vehicle parameters Application
Time after passes Weight No. of intensity
application per day (Mg) (tons) wheels (L/m2)
2-116 days 410 27 30 9.2 3.2
7-41 days 94 34 38 6.2 3.8
4-35 days 97 39 43 6.0 4.5
1.0-2.8 hr 1,200 44 49 6.0 0.1
Dilution
ratio Least-squares fit of
(L/L H20) PM,0 control efficiency3 (%)
1:4 102-0.00113 V
1:4 94.9-0.0134 V
1:7 100-0.00430 V
N/A 102-0.179 V
V represents cumulative vehicle passes after application. Complete mitigation is assumed immediately after application (i.e.,
c = 100 & V = 0).
Run AJ-6 was not used in developing the equations for water.
-------
TABLE 3-16. FIELD DATA ON UNPAVED ROAD WATERING CONTROL EFFICIENCY'
f
No. of
Location tests
N. Dakota 4
New Mexico 5
Ohio 3
Missouri 2
Month
October
July/Aug.
November
September
Applic.
intens.
(L/m2)
0.2
0.2
0.6
1.9
Avg. time
between
applic.
(hr)
1.8
2.0
4.5
2.8
Avg.
traf.
rate
(hr !)
40
23
98
72
Avg./
poten.
evap.
(mm/hr)
0.084
0.23
0.042
0.26
Avg.Av
control
eff ^ -^
(X)
59
69
77
88
a Reproduced from
b
Table 5-3 of
B t
Reference
13.
-, • •
t
• •
i _
size has been observed to date for watering.
^ £><
3-55
-------
TABLE 3-17. SUMMARY OF AVAILABLE PM,0 CONTROL EFFICIENCY DATA FOR WATER SPRAYS (OPEN DUST SOURCES)5
CO
i
en
cr>
Type of
process
Chain feeder
to belt
transfer
Belt-to-belt
transfer
Grizzly
transfer
to bucket
elevator
Conveyor
transport
and
transfer
Process
design/
Type of operating
material parameters
Coal 3 ft drop;
8 tons coal
per load
Coal Not specified
Run of mill Not Specified
sand
Coal 2 Belts; 0.91
m and 1.07 m
widths;
~ 500 m
length
Control system
parameters
8 Sprays, 2.5 gpm,
above belt only
8 Sprays, 2.5 gpm +
1 spray on under-
side of belt
8 Sprays, 2.5 gpm,
above belt only
8 Sprays, 2.5 gpm +
1 spray on under-
side of belt
Liquid vol. 757 mL
Liquid vol. 1,324 mL
Liquid vol. 1,324 mLc
Liquid vol. 1,324 mLd
3 Spray bars/belt,
underside of tail
pulley, 5-10 cc
H20/sec per bar,
Delevan ''fanjet"
sprays
Control .
efficiency
56%
81%
53%
42%
46%
58%
54%
54%
65-75%
Comments
Control applied at a
point 5 transfers
upstream
Control applied at a
point 5 transfers
upstream
Individual test values
not specified; no
airflow data or QA/
QC data
a Reproduced
** A^V f A
from Table 5-8 of Reference
13. 1 ft = 3.28 m; 1
ton = 0.91 Mg;
.
1 gal. = 3.79 L.
p* ^^^^.^ A «» nu
c Water + 1.5% surfactant.
d Water + 2.5% surfactant.
-------
TABLE 3-18. SUMMARY OF AVAILABLE PM,0 CONTROL EFFICIENCY DATA FOR FOAM SUPPRESSION SYSTEMS
(OPEN DUST SOURCES)3
tn
Type of
process
Belt-to-belt
transfer
Belt-to-bin
transfer
Bulk loadout
Screw-to-
belt
transfer
Bucket ele-
vator dis-
charge
Belt-to-belt
transfer
Feeder bar
discharge
Grizzly
transfer
to bucket
elevator
Type of
material
Sand
Sand
Sand
Sand
Sand
Sand
Sand
Run of mill
sand
Process
design/
operating
parameters
Sand temp.
~ 120°F
Sand temp.
~ 120°F
Sand temp.
~ 120°F
174 tons/hr
Sand temp.
~ 190°F
179 tons/hr
Sand temp.
~ 190°F
193 tons/hr
Sand temp.
~ 190°F
191 tons/hr
Sand temp.
~ 190°F
Not specified
Control system Control ^
parameters efficiency
Not specified 19.7%
Not specified 32.7%
Not specified 65.3%
Moisture = 0.25% 10%
Moisture = 0.18% 8%
Moisture = 0.18% 7%
Moisture = 0.19% 2%
Foam rate = 10.5 ft3/ 92%
ton sand
Liquid rate = 0.38
gal/min
Comments
Efficiency based on
concentration only
Efficiency based on
concentration only
Efficiency based on
concentration only.
Efficiency based on
concentration only
Efficiency based on
concentration only
Efficiency based on
concentration only
Efficiency based on
concentration only
Foam rate =8.2 ft3/
ton sand
Liquid rate = 0.34
gal/min
Foam rate = 7.5 ft3/
ton sand
Liquid rate = 0.20
gal/min
(continued)
74%
-------
TABLE 3-18. (concluded)
OJ
en
00
Process
design/
Type of Type of operating
process material parameters
Grizzly Run of mill Not specified
Chain feeder Coal 3- ft drop,
to belt 8 tons coal
transfer per load
Belt-to-belt Coal Not specified
transfer
Control system Control .
parameters efficiency Comments
Foam rate =
ton sand
Liquid rate
gal/min
Foara rate =
ton sand
Liquid rate
gal/min
Liquid vol.
Liquid vol.
Liquid vol.
50 psi H20,
reagent,
15-20 cfm
applied
50 psi H20,
reagent,
15-20 cfm
applied
4.8 ft3/ 0%
= 0.18
2.6 ft3/ 0%
= 0.13
1,420 mL 91%
1,300 mL 73%
764 mL 68%
2.5% 96% Efficiency based on
4 nozzles concentration only
foam
2.5% 71% Control applied at a
4 nozzles point 5 transfers
foam upstream
Reproduced from Table 5-9 of Reference 13. 1 ft3 = 28.32 m3; 1 ton = 0.91 Mg; 1 gal. = 3.79 L;
1 Pa = 1.45(10) 4 psi.
Control efficiency values are for respirable dust which is approximately the same as
-------
TABLE 3-19. SUMMARY OF AVAILABLE PM,0 CONTROL EFFICIENCY DATA FOR PLUME AFTERTREATMENT SYSTEMS
(OPEN DUST SOURCES)3
en
Type of process
Belt conveyor
Drop box
Type of
material
Copper con-
centrate
Copper con-
centrate
Process design/
operating parameters
Not specified
Not specified
Fogger system
1-Ransburg REA fogger
mounted above belt
discharge;
WFR = 30-60 cc/min
AF = not specified
1-Ransburg REA fogger
in drop box enclosure;
Average
control
efficiency
64-77%
65.4%
Boxcar unloading Silica sand Not specified
Belt conveyor Crushed ore
Conveyor width = 1.5 m
Belt speed = 152 m/min
Ventilation rate =
15-61 m/min
WFR = not specified
AF = not specified
4-Ransburg REA foggers
located 90° apart
around source;
WFR = 30 cc/min/fogger
AF = not specified
6-Keystone Dynamics Model
109s located 1.5 m
above A/el t (spray con-
current w/direction of
belt movement);
WFR = 300 cc/min/fogger
AF = supply pressure =
34.4-kPa
89%
0%
Includes only results of field testing. Reproduced from Table 5-10 of Reference 11.
The Ransburg and Keystone foggers are based on the original Hoenig design which uses induction
charging and commercial spray nozzles. WFR = water flow rate; AF = airflow to fogger(s).
Control efficiency values for respirable dust which is approximately the same as PM10.
ciency ranges include average efficiency for both positively/negatively charged fog.
Effi-
-------
REFERENCES FOR SECTION 3
1. U.S. Environmental Protection Agency. Control Techniques for Particu-
late Emissions from Stationary Sources - Volumes 1 and 2. EPA-450/3-
81-005, Emission Standards and Engineering Division, Research Triangle
Park, NC, September 1982.
2. White, H. J. Industrial Electrostatic Precipitation. Addison-Wesley
Publishing Company, Reading, MA, 1963.
3. Portius, D. H., et al. Fine Particle Charging Experiments. EPA-600/
2-77-173, U.S. Environmental Protection Agency, Research Triangle
Park, NC, August 1977.
4. McDonald, J. R. A Mathematical Model of Electrostatic Precipitation
(Revision I), Volume I, Modeling and Programming. EPA-600/7-78-llla,
U.S. Environmental Protection Agency, Research Triangle Park, NC, June
1978.
5. Helfrich, D. J., and T. Ariman. "Electrostatic Filtration and the
Apitron - Design and Field Performance" in Proceedings: Symposium on
New Concepts for Fine Particle Control. EPA-600/7-78-170, U.S. Envi-
ronmental Protection Agency, Research Triangle Park, NC, August 1978.
6. Dennis, R. , and H. A. Klemm. Fabric Filter Model Format Change, Vol-
ume I, Detailed Technical Report. Final Report, EPA Contract No. 68-
02-2607, Task No. 8, GCA Technology Division, Bedford, MA, January
1969.
7. Dennis, R., et al. Filtration Model for Coal Fly Ash with Glass
Fabrics. EPA-600/7-77-084, U.S. Environmental Protection Agency,
Research Triangle Park, NC, August 1977.
3-60
-------
8. Dennis, R., and H. A. Klemm. "Verification of Projected Filter System
Design and Operation," in Symposium on the Transfer and Utilization of
Particulate Control Technology, Volume 2, Fabric Filters and Current
Trends in Control Equipment. EPA-600/7-79-044b, U.S. Environmental
Protection Agency, Research Triangle Park, NC, February 1979.
9. Calvert, S., et al. Wet Scrubber System Study, Volume I, Scrubber .
Handbook. EPA-R2-72-118a, U.S. Environmental Protection Agency,
Research Triangle Park, NC, August 1972.
10. Yung, S-C. , et al. Venturi Scrubber Performance Model. EPA-600/2-77-
172, U.S. Environmental Protection Agency, Washington, DC, August 1977.
11. Reider, J. P., and R. F. Hegarty. Fine Particle Emissions Information
System: Annual Report (1979). EPA-600/7-80-092, U.S. Environmental
Protection Agency, Washington, DC, May 1980.
12. Larkin, R. J. Environmental Assessment Data Systems: Systems Overview
Manual. EPA-600/8-80-005, U.S. Environmental Protection Agency,
Research Triangle Park, NC, January 1980.
13. Cowherd, C., et al. Identification, Assessment, and Control of Fugi-
tive Particulate Emissions. Final Report, EPA Contract No. 68-02-3922,
Midwest Research Institute, Kansas City, MO, April 1985.
14. Radkey, R. L., and P. B. MacCready. A Study of the Use of Porous Wind
Fences to Reduce Particulate Emissions at the Mohave Generating Sta-
tion. AV-R-9563, AeroVironment, Inc., Pasadena, CA, 1980.
15. Duncan, M. , et al. Performance Evaluation of an Improved Street
Sweeper. Contract No. 68-09-3902, U.S. Environmental Protection
Agency, Research Triangle Park, NC, February 1984.
3-61
-------
16. McDermott, H. J. Handbook of Ventilation for Contaminant Control.
Fifth Printing, Ann Arbor Science Publishers, Inc., Ann Arbor, MI,
1983.
17. Kashdan, E. R., et al. Technical Manual: Hood System Capture of Pro-
cess Fugitive Particulate Emissions. Contract No. 68-02-3953, U.S.
Environmental Protection Agency, Research Triangle Park, NC, January
1985.
18. McCoy, J., et al. Evaluation of Charged Water Sprays for Dust Control,
Contract H0212012, U.S. Bureau of Mines, Washington, DC, January 1983.
19. Muleski, G. E., et al. Extended Evaluation of Unpaved Road Dust Sup-
pressants in the Iron and Steel Industry. EPA-600/2-84-027, U.S.
Environmental Protection Agency, Research Triangle Park, NC, February
1984.
3-62
-------
SECTION 4.0
ESTIMATION OF CONTROL COSTS AND COST EFFECTIVENESS
Development and evaluation of PMio emission control strategies require
analyses of the relative costs of alternative control measures. Cost
analyses are used by control agency personnel to develop overall strategies
for a specific geographical area or to evaluate plant-specific control
strategies. Industry personnel perform cost analyses to evaluate control
alternatives for a particular source or to develop a plant-wide emissions
control strategy. Although the details of these analyses may vary with the
objective of the analysis and the availability of cost data, the general
format is similar.
The primary goal of any cost analysis is to provide a consistent com-
parison of the real costs of alternative control measures. The objective
of this section is to provide a methodology that will allow such a compari-
son. It will describe the overall structure of a cost analysis and provide
the procedures and resources for conducting the analyses. Sources of cost
information and mechanisms for cost updating also are provided.
The approach outlined in this section will focus on cost effectiveness
as the primary comparison tool. Cost effectiveness is the ratio of the an-
nual ized cost of control to the amount of emissions reduction achieved.
Mathematically, cost effectiveness is defined by:
c* _ Ca (4-1)
C ~
4-1
-------
where: C* = cost effectiveness ($/mass of PM10 emissions reduction)
C, = annualized cost of the control measure ($/year)
a
AR = reduction in annual emissions (PM10 mass/year)
This general methodology was chosen because it is applicable equally to dif-
ferent controls that achieve an equivalent emissions reduction on a single
source and to controls that achieve varied reductions over multiple sources.
The discussion is divided into four subsections. The first subsection
describes general cost analysis methodology including the various types of
costs that should be considered and presents methods for calculating those
costs. The second subsection identifies the primary cost elements associ-
ated with each of the alternative control systems identified in Section 3.0.
The third subsection identifies generalized cost estimate procedures (i.e.,
graphs and tables) for typical control scenarios. The fourth subsection
presents example cost calculations for estimating control costs for typical
control scenarios.
4.1 GENERAL COST METHODOLOGY
Calculation of cost effectiveness can be accomplished in four steps.
First, the alternative control/cost scenarios are selected. Second, the
capital costs of each scenario are calculated. Third, the annualized costs
for each of the alternatives are developed. Finally, the cost effectiveness
is calculated after consideration of the level of emissions reduction.
The general approach for performing each of the four steps is described
below. This approach is intended to provide general guidance for cost com-
parison and should not be viewed as a rigid procedure that must be followed
in detail for all analyses. Some elements of the analysis may be omitted
by choice or because of resource or informational constraints. However,
for comparisons to be valid, these cautions should be observed: (1) all
control scenarios should be treated in the same manner; and (2) cost ele-
ments that vary radically between cost scenarios should not be omitted.
4-2
-------
4.1.1 Select Control/Cost Scenarios
Prior to the cost analysis, general control measures or strategies will
have been identified. These measures or strategies will fall into one of
the major classes of PM10 emission control techniques that were identified
in Section 3.0. The first step in the cost analysis is to select a set of
specific control/cost scenarios from the general techniques. The specific
scenarios will include definition of the major cost elements and identifica-
tion of specific implementation alternatives for each of the cost elements.
Each of the general control techniques identified in Section 3.0 has
several major cost elements, which include capital equipment and operation/
maintenance (O&M) items. For example, the major cost elements for chemical
stabilization of an unpaved road include: (a) acquiring the chemical;
(b) storing the chemical; (c) preparing the road; (d) mixing the chemical
with water; and (e) applying the chemical solution. The next step in any
cost analysis is definition of these major cost elements. Information is
provided in Subsection 4.2 on the major cost elements associated with each
of the general techniques defined above.
For each major cost element, several implementation alternatives can
be chosen. Options within each cost element include: buying or renting
equipment; shipping chemicals by railcar, truck tanker, or in drums via
truck; alternative sources of power or other utilities; and use of plant
personnel or contractors for construction and maintenance.
4.1.2 Develop Capital Costs
The capital costs of a.i emissions control system are those direct and
indirect expenses incurred up to the date the control system is placed in
operation. These capital costs include: actual purchase expenses for
capital equipment; labor and utility costs associated with installation of
the control system; and system shakedown and start-up costs. In general,
direct capital costs are the costs of equipment and auxiliaries and the
labor, material, and utilities needed to install the equipment. These
costs include system instrumentation and interconnection of the system.
4-3
-------
Capital costs also include any cost for site development necessitated
by the control system. For example, if a fabric filter on a capture/col-
lection system requires an access road for removal of the collected dust,
the access road is included as a capital expense. The types of direct costs
typically associated with emissions control systems are included in Table 4-1.
Indirect costs are associated costs incurred by the facility but not
directly attributable to specific equipment. Items in this category ar'e1:
I. Engineering costs — include administrative, process, project, and
general; design and related functions for specifications; bid analysis;
special studies; cost analysis; accounting; reports; purchasing; procure-
ment; travel expenses; living expenses; expediting; inspection; safety;
communications; modeling; pilot plant studies; royalty payments during con-
struction; training of plant personnel; field engineering; safety engineer-
ing; and consultant services.
2. Construction and field expenses — include costs for temporary field
offices; warehouses; craft sheds; fabrication shops; miscellaneous buildings;
temporary utilities; temporary sanitary facilities; temporary roads; fences;
parking lots; storage areas; field computer services; equipment fuel and
lubricants; mobilization and demobilization; field office supplies; telephone
and telegraph; time-clock system; field supervision; equipment rental; small
tools; equipment repair; scaffolding; and freight.
3. Contractor's fee — includes costs for field-labor payroll; super-
vision field office; administrative personnel; travel expenses; permits;
licenses; taxes; insurance; field overhead; legal liabilities; and labor
relations.
4. Shakedown/start-up — includes costs associated with system startup
and shakedown.
5. Contingency costs—the excess account set up to deal with uncer-
tainties in the cost estimate including unforeseen escalation in prices,
malfunctions, equipment design alterations, and similar over-runs.
4-4
-------
The values for these items will vary with the specific operations to
be controlled and the types of control systems used. Typical ranges for
indirect costs based on the total installed cost of the capital equipment
are shown in Table 4-2.
4.1.3 Determine Annual i zed Costs
Ihe-mast-comm&R- basis for comparison of alternative control systems is
by annual ized cost. The annual ized cost of an emission control system in-
cludes operating costs such as labor, materials, utilities, and maintenance
as well as the annual ized cost of the capital equipment. The annual ization
of capi tal costs is^=c=3ass4ea4=engi-neer4ng=eeonomre^
te-wfei-Gh takes into account the fact that money has time value. These an-
nual ized costs depend on the interest rate paid on borrowed money or poten-
tial interest lost on diverted company money, the useful life of the equip-
ment, and depreciation rates of the equipment.
The components of the annual ized cost of implementing a particular
control technique are presented in Table 4-3. The operation and maintenance
costs reflect increasing frequency of repair as equipment ages, along with
increased costs due to inflation for parts, energy, and labor. On the other
hand, costs recovered by tax credits or deductions are considered income.
Mathematically, the annual ized costs of control equipment can be calculated
from:
Ca = (CRF x Cp) + CQ + 0.5 C0 (4-2)
where: C, = annual ized costs of control equipment ($/year)
a
CRF = capital recovery factor (I/year)
C = installed capital costs ($)
C = direct operating costs ($/year)
0.5 = plant overhead factor
The components of this equation are described below.
4-5
-------
The annualized cost of capital equipment is calculated by using a
capital recovery factor (CFR). The capital recovery factor combines inter-
est on borrowed funds and depreciation into a single factor. It is a func-
tion of the interest rate and the overall life of the capital equipment and
can be estimated by the following equation:
CRF = i(1 +'1)n (4-3)
(1 + i)n - 1
where: i = interest rate (annual percent as a fraction)
n = economic life of the control system (years)
The other major components of the annualized cost are operation and
maintenance costs (direct operating expenses) and associated plant overhead
costs. Operation and maintenance costs elements typically include1:
1. Utilities—include water for process use and cooling; steam; and
electricity to operate controls, fans, motors, pumps, valves, and lighting.
2. Fuel costs—include the incremental cost of the fuel, where more
than the normal supply is used.
3. Raw materials—include any chemicals needed to operate the system.
4. Operating labor—includes supervision and the skilled and un-
skilled labor needed to operate, monitor, and control the system.
5. Maintenance and repairs--include the manpower and materials to keep
the equipment operating efficiently. The function of maintenance is both
preventive and corrective, to keep down-time to a minimum.
6. Byproduct costs—in systems producing a salable product, these
would be a credit for that product; in systems producing a product for dis-
posal, these would be the costs of disposal.
4-6
-------
Another component of the operating cost is overhead, which is a busi-
ness expense not charged directly to a particular part of the process but
is allocated to it. Overhead costs include: administrative, safety, en-
gineering, legal, and medical services; payroll; employee benefits; recre-
ation; and public relations. As suggested by Equation 4-3, these charges
are estimated to be approximately 50% of direct operating costs.
Alternative Cost Estimation Procedures
Several methods with varying levels of accuracy are available for esti-
mating the costs of control measures. A brief description of these methods
is presented.
4.1-4:1 Detailed Engineering Cost Analysis--
The detailed cost estimate can provide accuracies of plus or minus 5%
depending on the level of engineering involved. Detailed estimates take
several months of engineering effort to produce process flow sheets, mass
and energy balances, plot plans, and equipment citing drawings to provide
the basis for subsequent cost analysis. After the package of specifications
is established, contractors and equipment manufacturers can proceed with
their analyses to provide a quotation for the specified equipment. This
level of cost estimation is typically performed after a formal decision has
been reached on the most cost-effective control alternative.
4.1.4:2 Study Estimates--
Study cost estimates can provide accuracies of plus or minus 30%.
Study estimates can be generally made within a few hours or days depending
on the availability of resources and unit cost information. These estimates
are produced from a factored method by establishing direct and indirect in-
i
stallation costs that are dependent on known capital equipment costs. The
technique used in Capital and Operating Costs of Selected Air Pollution Con-
trol Systems is a study estimate1. Study estimates are used to help iden-
tify the most cost-effective control alternative(s) and specification(s) to
begin a detailed engineering cost estimate. Subsection 4.4.1 provides an
example study estimate for illustration.
4-7
-------
4.1.4".3 Generalized Cost Estimate Procedures--
Generalized cost estimate procedures provide accuracies of plus or
minus 50%, resulting in order of magnitude estimate of the anticipated
costs. These estimates can be made rapidly by referring to a table, graph,
or known cost level for a similar design and a different capacity or scale.
The "six-tenth factor method" is used to adjust mathematically the
known cost for a particular system design for another similar system with a
different scale. Scaled estimates are calculated by use of the following
general equation:
C2 = Ci (^-)n (4-4)
where: C2 = cost of desired control device
G! = cost of known control device
r2 = capacity of desired control device
r1 = capacity of known desired control device
n s 0.6 (can vary from 0.5 to 0.7)
This method consists of using the above equation to relate the primary cost
variable with total costs and neglecting the effect of other cost variables.
Use of this method should be limited to cases where no other cost informa-
tion is available.
Another generalized cost estimate procedure is the use of graphs or
tables that relate cost values to the primary cost variable. Graphs of this
type also provide accuracies of plus or minus 50%.
Section 4.3.1 presents graphs that show the relationship between gas
flow rate and estimated costs for the three conventional types of control
equipment for ducted sources. The graphs in Section 4.3.1 also depict con-
trol costs for the respective secondary cost factor. The secondary cost
factors are pressure drop and specific collection area (SCA) for wet scrub-
bers and electrostatic precipitators (ESP's), respectively. For fabric
4-8
-------
filters, the secondary cost variable is based on the different design types
that are characterized by cleaning method, air-to-cloth ratio, and bag ma-
terial. Sections 4.3.2 and 4.3.3 present tables with generalized control
costs for process fugitive sources and open sources, respectively.
4.2 COST ELEMENTS AND SOURCES OF DATA
4.2.1 Cost Elements
The cost methodology outlined in Section 4.1 requires that the analyst
define and select alternative control/cost scenarios and develop costs for
the major cost elements within these scenarios. The objective of this sec-
tion is to identify the implementation alternatives and major cost elements
associated with the emission reduction techniques identified in Section 3.0.
For ducted sources, the control techniques addressed are wet scrubbers,
electrostatic precipitators, and fabric filters. For process fugitive
sources, the primary controls discussed are wet suppression, capture/col-
lection, and plume aftertreatment. For open dust sources, the control
techniques addressed are wet dust suppression, surface cleaning, and paving.
Control alternatives for ducted sources are presented in Tables 4-4,
4-5, and 4-6 for wet scrubbers, ESP's, and fabric filters, respectively.
Process fugitive control alternatives are presented in Tables 4-7 through
4-9. Table 4-7 outlines alternatives for wet suppression systems and Ta-
ble 4-8 alternatives for a typical capture/collection system. The options
shown in Table 4-8 are applicable for active enclosures, capture hoods, and
receiving hoods. Table 4-9 presents implementation alternatives for plume
aftertreatment systems.
Optional approaches for open dust source control measures^are presented
in Tables 4-10 through 4-13. Table 4-10 presents implementation alterna-
tives for water and chemical dust suppressant systems for stabilizing un-
paved travel surfaces. Table 4-11 presents options for improving paved
travel surfaces: sweeping, flushing, and a combination of flushing and
4-9
-------
broom sweeping. Tables 4-12 and 4-13 present alternatives for wet suppres-
sion and paving of streets or parking lots, respectively.
After control scenarios are selected, the analyst must then estimate
both the capital cost of the installed system and the operating and mainte-
nance costs. The indirect capital cost elements common to all systems were
identified in Table 4-2. The direct capital cost elements and operation
and maintenance cost elements, which are unique to each type of PM10 emis-
sion control system, are identified in Tables 4-14 through 4-22.
Ducted source control cost elements for wet scrubbers, ESP's, and
fabric filters are presented in Tables 4-14, 4-15, and 4-16, respectively.
Process fugitive control cost elements for wet suppression, capture/collec-
tion, and plume aftertreatment are presented in Tables 4-17, 4-18, and 4-19,
respectively. Open dust source control cost elements for stabilizing un-
paved travel surfaces are presented in Table 4-20; for improving paved
travel surfaces, in Table 4-21; and for paving, in Table 4-22.
4.2.2 Sources of Data
Cost estimate procedures and information for ducted source control mea-
sures are contained in References 1 through 20. Venturi scrubber cost in-
formation is contained in References 1 and 11. Electrostatic precipitator
cost information is contained in References 1 and 10. Fabric filter cost
information is contained in References 1 and 12. Wastewater treatment cost
information is contained in References 18 and 21. Cost information for
process fugitive sources and open dust controls are contained in References
20, 21, 22, and 23.
Cost information for updating unit costs are contained in Reference 1,
Chemical Engineering issues, Producer Prices and Price Indexes and Employ-
ment and Earning Reports published by the U.S. Department of Labor, Bureau
of Labor Statistics.
4-10
-------
4.3 /GENiflAtTZED COST ESTIMATE PROCEDURES
This subsection presents generalized cost information for quick study
estimates (±50%) for the common PM10 control measures. Development and
evaluation of PM10 control strategies require analyses of the relative cost
effectiveness of alternative control measures. Quick determination of the
cost effectiveness of alternative controls is helpful for screening purposes
because the least cost-effective options can be eliminated. Thus, the most
cost-effective alternatives can then be studied in detail. Combined use of
the generalized cost procedures in this section with the detailed procedures
presented in Section 4.2 will provide increased accuracies when needed.
4.3.1 QefteraTTzed Cost Estimation for Point Source Control Alternatives
This section presents generalized cost data for three point source con-
trol alternatives. Three cost curves representing purchased equipment
costs, total capital costs, and annualized costs are given for each type of
control. All costs were estimated from information contained in References 1
and 30 and updated to April 1985 dollars.
4.3.1.2 Wet Scrubber Generalized Cost Estimation—
Figure 4-1 shows purchased equipment costs for a venturi scrubber with
a combined throat and carbon steel construction for design pressure drops
of 20, 40, and 60 in. water column (w.c.). Figures 4-2 and 4-3 present
capital and annualized cost for a venturi scrubber with carbon steel and
stainless steel construction, respectively, for pressure drops of 20, 40,
and 60 in. w.c.
4.3.1.2 ESP Generalized Cost Estimation--
Figures 4-4 shows purchased equipment costs for an insulated ESP with
carbon steel construction for four cases: moderate-to-low resistivity dust
for total particulate control efficiencies of 99.5 and 99.9%; and high
resistivity dust for total particulate control efficiencies of 99.5 and
99.9%. Figure 4-5 shows capital and annualized costs for the four cases.
4-11
-------
4.3.1.3 Fabric Filter Generalized Cost Estimation--
Figure 4-6 shows purchased equipment costs for three fabric filter de-
signs: (1) reverse air cleaning with air-to-cloth ratios ranging from 1.5
to 3.3 ft/min with nylon bags; (2) shake cleaning with an air-to-cloth
ratios ranging from 2.0 to 3.3 ft/min with nylon bags; and (3) pulse clean-
ing with an air-to-cloth ratios ranging from 3.3 to 7.0 ft/min with Nomex®
bags. Figures 4-7 and 4-8 show capital and annualized costs for fabric
filters with stainless steel and carbon steel construction, respectively,
for the three cases.
Each of the control system cost curves include the costs of auxiliary
equipment normally associated with such a system. In some instances, one
may wish to know what the system would cost either with or without the
ductwork, fan, and fan drive. The capital and annualized costs of the com-
ponents are shown in Figures 4-9 and 4-10.
4.3.2 Generalized Cost Estimation for Process and Open Source Fugitive
Control Alternatives
Table 4-23 presents typical costs for wet suppression of process fugi-
tive sources and Table 4-24 similar costs for wet suppression of open
sources. Cost estimates for stabilization of open sources and improvement
of paved travel surfaces are presented in Tables 4-25 and 4-26, respectively.
4.4 EXAMPLE COST ESTIMATE CALCULATIONS
This section presents example calculations for estimating typical con-
trol costs of a point source, a process fugitive source, and an open source.
The example calculations illustrate the complete procedure for estimating
capital costs, operating and maintenance costs, annualized costs, and cost
effectiveness.
4-12
-------
4.4.1 Typical Ducted Source Control Cost Estimate
The example calculation is based on applying a venturi scrubber with a
waste treatment system to control the emissions from a flash dryer in the
diatomite processing industry. Tables 4-27 and 4-28 are presented as guide-
lines and working forms to be used to identify and specify the cost elements
to be estimated. Table 4-27 is used to specify the alternatives necessary
to estimate the costs of the venturi scrubber to be installed for this ex-
ample. Table 4-28 is used to identify the scope of cost elements to be
estimated. Tables 4-29 and 4-30 present the details, equations, and refer-
ences for estimating capital costs and annualized costs, respectively, for
a typical ducted source.
The costing technique demonstrated by this example (and used in Refer-
ence 1) is the factored method of establishing direct and indirect instal-
lation costs based on known equipment costs. The resulting cost estimate
using this method can provide accuracies of plus or minus 30%. A descrip-
tion of the calculations used to estimate capital and annualized costs and
cost effectiveness for the sample case follows.
Capital costs: Estimation of the capital costs for this example case
was performed using the factored method (Reference 1), with the exception
of the wastewater treatment system (Reference/26J>>and co.ntinuous pressure
drop and liquid flow monitoring system (References 27, 28,29J^->Table 4-29
presents the capital costs for each component in the venturi scrubber system
along with specifications and references.
The control devices and auxiliary equipment items are individually
costed from identified graphs and tables contained in Reference 1. Current
and appropriate cost factors are identified and used to update the December
1977 cost values (used in Reference 1) to April 1985 cost values^ Sources
of these cost factors are also included in Table 4-29.
Wastewater treatment costs were obtained from Reference 26 and updated
from December 1982 values to April 1985 values. Continuous monitor costs
4-13
-------
were obtained from vendors and updated from February 1983 values to April
1985 values.
Total annual ized costs: Total annual i zed costs are determined by con-
sidering all the component charges for: utilities; operating labor; total
maintenance; total overhead; product recovery; and capital charges. Product
recovery costs, when applicable, represent a cost savings. Annual ized costs
are determined by the following equation:
Annual ized costs = utility cost + operating labor + total maintenance
.
cost + overhead costs + capital charges -, product recovery eos-ts-
f- »
Substituting appropriate dollar values:
Annual ized costs = 487,299 + 31,105 + 27,200 + 44,484 + 365,497 - 0
= $955,565/yr
Cost effectiveness: Cost effectiveness, as discussed previously, is
calculated by use of Equation 4-1:
C* =
_ Ca
"AIT
The estimated PMio emission reduction is determined by the following
equation:
AR = 4.285(10)"6 CPM10 x QQS x H x Ei0 (4-5)
where: AR = annual reduction in PMio emissions (jnali/year);
CPM10 = inlet concentration of PMio to control device
(gr/dscf);
Qg<- = airflow rate to control device (dscf/min);
H = hours of operation (h/yr);
EIO = PMio control efficiency;
and 4.285 x 10"6 (mi°n) = conversion factor.
4-14
-------
Substituting appropriate values:
AR = (2.8 -SI-)(26,770 ^)(8,000 h/yr)(0.95)(4.285 x 10"6 m1'n"ton)
dscf min h-gr
= 2,440 ton/yr
Cost effectiveness for PMio is then calculated by substituting appro-
priate values:
c* = _Ca_
AR
C* = ($955,585/yr)/(2,440 ton/yr)
C* = $392/ton of PMio
4.4.2 Typical Fugitive Control Cost Estimates
The example calculation is based on controlling PMio emissions by wet
suppression at a typical crushing plant. Tables 4-31 and 4-32 are presented
as guidelines and working forms to be used to identify and specify the cost
elements to be estimated for this example case. Table 4-33 presents de-
tailed calculations and references for typical capital costs, operating
costs, annualized costs, and cost effectiveness values.
The example calculation is based on controlling emissions by stabilizing
unpaved travel surfaces with a choice of two commercially available dust sup-
pressants. Table 4-34 presents the steps necessary to estimate costs and
cost effectiveness. Tables 4-35 through 4-38 contain supplemental informa-
tion for Table 4-34.
4-15
-------
TABLE 4-1. TYPICAL CAPITAL COST ELEMENTS
Equipment costs
Equipment installation
Instrumentation
Duct work
Piping
Electrical
Site development
Buildings
Painting
Insulation
Structural support
Foundations
Supporting administrative structures
Control panels
Access roads or walkways
TABLE 4-2. TYPICAL VALUES FOR INDIRECT CAPITAL COSTS1
Cost item
Range of values
Engineering
Construction and field
expenses
Contractor's fee
Shakedown/startup
Contingency
8Jtp_2jO%__oJ installed cost. High value
for small projects; low value for large
projects.
/"/to 70%b>f iastal led cost
V -^
"l'0""tb 30%>f total direct and indirect
costs depending upon accuracy of estimate.
Generally, 20 percent is used in a study
estimate.
4-16
-------
TABLE 4-3. TYPICAL ANNUALIZED COST ELEMENTS
(.nil d
Direct operating costs
Operating labor
Operator
Supervisor
Operating materials
Maintenance
Labor
Material
Replacement parts
Utilities
Electricity
Fuel oil No. 2
Natural gas
Plant water
Water treatment
Steam
Compressed air
Waste disposal
$12.35/man-hour
15% of operator
As required
$13.60/man-hour
Equal to maintenance labor costs
As required
$0.0715/kWh
$0.809/gal.
$3.11/MCT
$0.60/1,000 gal,
$1.55/1,000 gal,
NAa
NA
As required
Indirect operating costs
Overhead
Property tax
Insurance
Administration
Capital recovery cost
80% of operating labor and
maintenance labor
1% of capital costs
1% of capital costs
2% of capital costs
[i(l+i)n] * [d+i)n-l], 1 = annual
interest rate, n = effective life;
example factor for 13% interest and
10 years equipment life = 0.1843
Credits
Recovered product
As required
NA = Not available.
4-17
-------
TABLE 4-4. -CONTROL ALTERNATIVES-FOR WET SCRUBBERS
I. Basic design decisions
A. What are the specifications of the gas stream to be controlled?
1. Maximum gas flow rate—actual and dry standard conditions
2. Gas temperature and moisture content
3. Increase in gas flow rate due to evaporative cooling, if
any
4. Particulate concentration and size distribution
B. What performance specifications are needed to achieve emission
reduction?
1. Collection efficiency
2. Pressure drop
3. Liquid-to-gas ratio
C. What materials of construction are required?
S6W.«&<1 A«°*ftT'
1. Metal thickness due to pressure drop and gas flow rate
2. Carbon steel or stainless steel
&?
D. What are the waste treatment and disposal requirements?
1. Once through water system/A\t>ta^f
2. Chemicals and equipment for treatment
3. Landfill or surface impoundment
E. What are the Res^ter-a^nts for retrofit?
1. Space limitations
2. Availability of water and surface impoundment
3. Minimum outage period
4, Avt.ilab.liii A
II. Construction/installation decisions
A. Who will install system?
1. Plant personnel
2. Contractor
B. Who is responsible for system shakedown/start-up?
1. Plant environmental staff
2. Plant personnel
3. Contractor
4-18
-------
TABLE 4-4. (concluded)
III. Operation/maintenance decisions
A. What instrumentation is needed for reliable operation?
1. Pressure drop meters
2. Liquid flow meters
3. Temperature indicators
4. Recorders and control panel
B. Who will perform routine maintenance?
1. Plant personnel
2. Contractor
C. How will collected particulate be disposed?
1. Returned to process
2. Landfilled
3. Surface impoundment
4-19
-------
TABLE 4-5. CONTROL ALTERNATIVES FOR ELECTROSTATIC PRECIPITATORS
I. Basic design considerations
A. What are the specifications of the gas stream to be controlled?
1. Maximum gas flow rate—actual and dry standard conditions
2. Gas temperature and moisture content
3. Resistivity
4. Particulate concentration and size distribution
B. What performance specifications are needed to achieve emission
reduction?
1. Collection efficiency
2. Specific collection area
3. Sectionalization
4. Precollector cyclones
C. What materials of construction are required?
1. Carbon or stainless steel
2. Insulated or uninsulated
D. How will collected material be handled?
1. Screw conveyor
2. Pneumatic transport
3. Slurry piping
4. Batch process
5. Need for fugitives control, if any
E. What are the restraints for retrofit?
1. Space
2. Electricity
3. Minimum outage period
II. Construction/installation decisions
A. Who will install system?
1. Plant personnel
2. Contractor
4-20
-------
TABLE 4-5. (concluded)
B. Who is responsible for system shakedown/startup?
1. Plant environmental staff
2. Plant personnel
3. Contractor
III. Operation/maintenance decisions
A. What instrumentation is needed for reliable operation?
1. Primary and secondary voltage and current meters
2. Indicators for plate and wire rapping
3. Temperature indicators
4. Recorders and control panel
5. Opacity monitor
B. Who will perform routine maintenance?
1. Plant personnel
2. Contractor
C. How will collected particulate be disposed?
1. Returned to process
2. Landfilled
3. Surface impoundment
4-21
-------
TABLE 4-6. £GNJJO:L^AbT€RNA=T=fVfS FOR FABRIC FILTERS
I. Basic design decisions
A. What are the specifications of the gas stream to be controlled?
1. Maximum gas flow rate—actual and dry standard conditions
2. Gas temperature and moisture content
3. Particulate concentration and size distribution
B. What performance specifications are needed to achieve emission
reduction?
1. Collection efficiency
2. Air-to-cloth ratio
3. Type of cleaning mechanism
4. Bag material . \
C. What materials of construction are required?
1. Carbon or stainless steel
2. Insulated or uninsulated
D. How will collected material be handled?
1. Screw conveyor
2. Pneumatic transport
3. Slurry piping
4. Batch process
5. Need for fugitive control, if any
E. What are the restraints for retrofit?
1. Space
2. Minimum outage period
II. Construction/installation decisions
A. Who will install system?
1. Plant personnel
2. Contractor
B. Who is responsible for system shakedown/startup?
1. Plant environmental staff
2. Plant personnel
3. Contractor
4-22
-------
TABLE 4-6. (concluded)
III. Operation/maintenance decisions
A. What instrumentation is needed for reliable operation?
1. Bag pressure drop meters
2. Bag cleaning indicators
3. Temperature indicators
4. Recorders and control panel
5. Opacity monitor
B. Who will perform routine maintenance?
1. Plant personnel
2. Contractor
C. How will collected particulate be disposed?
I. Returned to process
2. Landfilled
3. Surface impoundment
D. How frequently will bag replacement occur?
1. As needed
2. Every year
3. Every other year
4-23
-------
TABLE 4-7. C@fcCERQt=Afc¥ERI*flfffVES FOR WET SUPPRESSION OF
PROCESS FUGITIVES
I. Basic design decisions
A. What type wet suppression system will be used?
1. Water spray
2. Water/surfactant spray
3. Micron-si zed foam
4. Combination system
B. What sources will be controlled?
C. What system layout will be used?
1. Centralized supply with headers for each source
2. Individual systems for some sources
II. Construction/installation decisions
A. Who will install system?
1. Contractor
2. Plant personnel
III. Operational decisions
A. What is the water source?
1. Plant wells
2. Local surface waters
3. City water system
B. Under what weather conditions will the system be needed?
1. Above freezing only
2. Below freezing
C. How will routine maintenance be provided?
1. Plant personnel
" 2. Maintenance contractor
4-24
-------
TABLE 4-8. CONJ=R^t=AbTERNAT=I=V€S FOR CAPTURE/COLLECTION SYSTEMS
I. Basic design decisions
A. What type hooding system best fits each source?
1. Enclosure
2. Capture hood
3. Receiving hood
B. What type of air pollution control device best meets plant
needs?
1. Cyclone
2. Wet scrubber
3. Fabric filter
C. How will collected particulate be handled?
1. Screw conveyor
2. Pneumatic transport
3. Slurry piping
4. Batch removal
D. What system layout will be used?
1. Multiple collection points ducted to centralized air
pollution control device
2. Dedicated air pollution control devices for each source
3. Mixed system
E. Who will design the system?
1. Outside design of total system
2. Plant design of system with vendor design of individual
components
II. Construction/installation
A. Who will install system?
1. Plant personnel
2. Contractor
B. Who is responsible for system shakedown/start-up?
1. Plant environmental staff
2. Plant operators
3. Contractor personnel
4-25
-------
TABLE 4-8. (concluded)
III. Operational decisions (dependent on type of system selected)
A. What electrical source will be used?
1. Public utility
2. Plant power system
B. What water source will be used?
1. Plant well
2. Local surface water
3. Public water system
C. How will routine maintenance be provided?
1. Plant personnel
2. Outside contractor
D. How will collected particulate be disposed?
1. Returned to process
2. Landfilled
3. Surface impoundment
4-26
-------
TABLE 4-9. CONTROL ALTERNATIVES FOR PLUME AFTERTREATMENT SYSTEMS
I. Basic design decisions
A. What sources are to be controlled?
B. What is the physical size of the source and resulting dust
plume?
C. Is the area sheltered from wind or cross drafts such that
aftertreatment can be effectively applied?
D. How many foggers or nozzles are to be used and where are
they to be positioned?
E. How will water and electric power be supplied to unit(s)?
1. Central system
2. Separate line(s) from multiple sources
II. Construction/installation decisions
A. Who will install system?
1. Contractor
2. Plant personnel
III. Operational decisions
A. What is the water source?
1. Plant wells
2. Local surface waters
3. City water system
B. What electrical source will be used?
1. Public utility
2. Plant power
C. Under what weather conditions will the system be needed?
1. Above freezing only
2. Below freezing
D. How will routine maintenance be provided?
1. Plant personnel
2. Maintenance contractor
4-27
-------
TABLE 4-10. CONTROL ALTERNATIVES FOR STABILIZATION OF
UNPAVED TRAVEL SURFACES
Dust suppressant type
Program implementation alternative Chemicals Water
I. Purchase and ship dust suppressant
A. Ship in railcar tanker (11,000-22,000 x
gal/tanker)
B. Ship in truck tanker (4,000-6,000 gal/ x
tanker)
C. Ship in drums via truck (55 gal/drum) x
II. Store dust suppressant
A. Store on plant property
1. In new storage tank x
2. In existing storage tank
a. Needs refurbishing x
b. Needs no refurbishing x
3. In railcar tanker
a. Own railcar x
b. Pay demurrage " x
4. In truck tanker
a. Own truck x
b. Pay demurrage x
5. In drums x
B. Store in contractor tanks x
III. Prepare road
A. Use plant-owned grader to minimize ruts x x
and low spots
B. Rent contractor grader x x
C. Perform no road preparation x x
IV. Mix dust suppressant/water in application
truck
A. Put suppressant in spray truck
1. Pump suppressant from storage tank x
or drums into application truck
2. Pour suppressant from drums into x
application truck, generally using
fork!ift
B. Put water in application truck
1. Pump from river or lake x x
2. Take from city water line x x
V. Apply suppressant solution via surface
spraying
A. Use plant owned application truck x x
B. Rent contractor application truck x x
4-28
-------
TABLE 4-11. CONTROL ALTERNATIVES FOR IMPROVEMENT OF PAVED
TRAVEL SURFACES
Program
implementation alternative
Control alternatives
Flushing
and
Broom- broom-
sweeping Flushing sweeping
I. Acquire flusher and driver
A. Purchase flusher and use plant
driver
B. Rent flusher and driver
C. Use existing unpaved road
watering truck
x
x
X
X
II. Acquire broom sweeper and driver
A. Purchase broom sweeper and
use plant driver
B. Rent broom sweeper and driver
III. Fill flusher tank with water
A. Pump water from river or lake
B. Take water from city line
IV. Maintain purchased flusher
V. Maintain purchased broom sweeper
x
x
x
x
x
x
x
4-29
-------
TABLE 4-12. CONTROL ALTERNATIVES FOR WET SUPPRESSION OF UNPAVED
SURFACES
Program implementation alternatives
I. Prepare road
A. Use plant owned grader to minimize ruts and low spots
B. Rent contractor grader
II. Put water into application truck
A. Pump from river or lake
B. Take from city water
III. Apply water via surface spraying
A. Use plant owned application truck
B. Rent contractor application truck
4-30
-------
TABLE 4-13. CONTROL ALTERNATIVES FOR PAVING
Program implementation alternative
I. Excavate existing surface to make way for
base and surface courses
A. 2-in. depth
B. 4-in. depth
C. 6-in. depth
II. Fine grade and compact subgrade
III. Lay and compact crushed stone base course
A. 2-in. depth
B. 4-in. depth
C. 6-in. depth
IV. Lay and compact hot mix asphalt surface
course (probably AC120-150)
A. 2-in. depth
B. 4-in. depth
C. 6-in. depth
4-31
-------
TABLE 4-14. CAPITAL EQUIPMENT AND O&M EXPENDITURE
ITEMS FOR WET SCRUBBERS
Capital Equipment
Scrubber
Separator
Quencher (precooler)
Radial tip fan
Fan motor
Motor starter
Fan damper(s)
Motor
Duct insulation
Slurry pump
Sump pump
Instrumentation and control panel f
(IT
O&M Expenditures
Utilities
Water
Electricity
Materials
Chemicals
Spare parts , , 1,^4. L-
vi Bfi^bTW t* ^V\ v~t*s*)
Labor
Operators
Maintenance
Supervision
4-32
-------
TABLE 4-15. CAPITAL EQUIPMENT AND O&M EXPENDITURE
ITEMS FOR ELECTROSTATIC PRECIPITATORS
Capital Equipment
Electrostatic precipitator
Precollector cyclone
Fan--backwardly curved blades
Fan motor
Motor starter
Fan damper(s)
Motor drive
Duct
Insulation
Instrumentation and control panel
Ash handling/removal
Hopper heaters
O&M Expenditures
Utilities
Electricity
Materials
Spare parts / /
ehsfo$&/ e-oir/reca^evf CreJ/r
Labor '
Operators
Maintenance
Supervision
4-33
-------
TABLE 4-16. CAPITAL EQUIPMENT AND O&M EXPENDITURE
ITEMS FOR FABRIC FILTERS
Capital Equipment
Fabric filter
Fan—backwardly curved blades
Fan motor
Motor starter
Motor drive
Fan damper(s)
Duct
Insulation
Ash handling/removal
Instrumentation and control panel
O&M Expenditures
Utilities
Electricity
Compressed air
Materials
Spare parts
Replacement bags
Labor
Operators
Maintenance
Supervision
4-34
-------
TABLE 4-17. CAPITAL EQUIPMENT AND O&M EXPENDITURE
ITEMS FOR WET SUPPRESSION OF
PROCESS FUGITIVE EMISSIONS
Capital Equipment
- Water spray systems
• Supply pumps
• Nozzles
• Piping (including winterization)
• Control system
• Filtering units
- Water/surfactant and foam systems only
• Air compressor
• Mixing tank
• Metering or proportioning unit
• Surfactant storage area
O&M Expenditures
- Utility costs
• Water
• Electricity
- Supplies
• Surfactant
• Screens
- Labor
• Maintenance
• Operation
4-35
-------
TABLE 4-18. CAPITAL EQUIPMENT AND O&M EXPENDITURE
ITEMS FOR CAPTURE/COLLECTION SYSTEMS3
Capital Equipment
- Dust collector
• Fabric filter or scrubber
• Concrete work
• Dust removal system
• Control instrumentation
• Monitoring instrumentation
- Hood(s) or enclosure(s)
- Ventilation system
• Fan
• Electrical wiring
• Ductwork
• Concrete support work
• Damper system
• Expansion joints
- Dust storage system
O&M Expenditures
- Utilities
• Electricity
• Water
- Supplies
• Replacement bags
• Fan motors
• Chemical additives for scrubber
- Labor
• System operation
• Control device maintenance and cleaning
• Ductwork maintenance
- Disposal of collected particulate
a Specific items included will depend on the control
scenario selected.
4-36
-------
TABLE 4-19. CAPITAL AND O&M EXPENDITURES FOR PLUME
AFTERTREATMENT SYSTEMS
Capital Equipment
- Fogging or spray heads (nonelectrostatic)
• Atomizers
• Supply pumps
Plumbing (including weatherization)
• Water filters
• Flow control system
- Electrostatic foggers or spray nozzles
Atomizer(s) and high voltage power supply
Water pumps and plumbing (including
weatherization)
• Water filters
• Flow control system
Power lines and electric utilities
O&M Expenditures
- Utility costs
• Water
Electricity
- Supplies
• Antifreeze agent(s)
• Screens
• Replacement electrodes (if applicable)
- Labor
Operation
• Maintenance
4-37
-------
TABLE 4-20. CAPITAL EQUIPMENT AND O&M EXPENDITURE
ITEMS FOR CHEMICAL STABILIZATION
OF UNPAVED TRAVEL SURFACES3
Capital Equipment
- Storage equipment
• Tanks
• Rail car
• Pumps
• Piping
- Application equipment
• Trucks
• Spray system
• Piping (including winterizing)
O&M Expenditures
- Utility or fuel costs
• Water
• Electricity
• Gasoline or diesel fuel
- Supplies
• Chemicals
• Repair parts
- Labor
• Application time
• Road conditioning
• System maintenance
Not all items are necessary for all systems. Spe-
cific items are dependent on the control scenario
selected.
4-38
-------
TABLE 4-21. CAPITAL EQUIPMENT AND O&M EXPENDITURE
ITEMS FOR IMPROVEMENT OF PAVED
TRAVEL SURFACES
Capital Equipment
- Sweeping
• Broom
• Vacuum system
- Flushing
• Piping
• Flushing truck
• Water pumps
O&M Expenditures
- Utility and fuel costs
• Water
• Gasoline or diesel fuel
- Supplies
Replacement brushes
- Labor
• Sweeping or flushing operation
• Truck maintenance
- Waste disposal
4-39
-------
TABLE 4-22. CAPITAL EQUIPMENT AND O&M EXPENDITURE
ITEMS FOR PAVING
Capital Equipment
- Operating equipment
• Graders
Paving application equipment
• Materials
• Paving material (asphalt or concrete)
• Base material
O&M Expenditures
- Supplies
• Patching material
" UbS^rfB-ce- re-ara-ffon ^V
• f-avtng * ^ J
Road maintenance
Equipment maintenance
4-40
-------
TABLE 4-23. TYPICAL COSTS FOR WET SUPPRESSION OF PROCESS
FUGITIVE SOURCES3
Source method
Initial cost
(April 1985
dollars)0
Unit operat-
ing cost
(April 1985
dollars0)
Rail car unloading station 48,700
(foam spray)
Rail car unloading station 168,000
(charged fog)
Conveyor transfer point 23,700
(foam spray)
Conveyor transfer point 19,800
(charged fog)
NR
NR
0.02 to
0.05/ton
material
treated
NR
Reference 20. NR = Not reported.
January 1980 costs updated to April 1985 cost by Chemical
Engineering Index. Factor = 1.315.
Based on use of 16 large devices at $10,500 each.
Based on use of three small devices at $6,600 each.
4-41
-------
TABLE 4-24. TYPICAL COSTS FOR WET SUPPRESSION OF
OPEN SOURCES3
Initial
capital cost Annual operating
(April 1985 cost (April 1985
Source method dollars) dollars)
Unpaved road-regular 17,100/truck 32,900/truck
watering
Storage pile-regular 18,400/system NR
watering
-------
TABLE 4-25. SELECTED COST ESTIMATES FOR STABILIZATION
OF OPEN DUST SOURCES3
Source/control
method
Initial
capital cost
(April 1985
dollars)0
Annual operating
cost (April 1985
dollars)0
Unpaved road-
chemicals (lignin
or coherex)
Unpaved road-
asphaltic paving
Exposed areas-
chemicals
Exposed areas-
asphalt paving
Storage piles-
surface crusting
chemicals
Exposed areas-
vegegation
7,800-19,700/mile 7,800-19,700/mile
44,700-80,200/mile 6,600-11,900/milec
1,060/acre
15,700/acre
18,400/system
200-790/acre
40-80/acre
NR
0.006-0.01/ft2
NR1
Reference 20. NR = Not reported.
January 1980 costs updated to April 1985 cost by Chemical
Engineering Index. Factor = 1.315.
Based on resurfacing every 5 years and 15% opportunity costs.
Dependent on type of vegegation planted, condition of soil,
and climate.
4-43
-------
TABLE 4-26. COST ESTIMATES FOR IMPROVEMENT OF PAVED TRAVEL
SURFACES
Initial
capital cost Annual operating
Source/control (April 1985 cost (April 1985
method dollars)3 dollars)3'0
Paved road-sweeping 6,580-19,700/truck 27,600/truck
Paved road-vacuuming 36,800/truck 34,200/truck
Paved road-flushing 18,400/truck 27,600/truck
a January 1980 costs updated to April 1985 cost by Chemical
Engineering Index Factor = 1.315. Reference 20.
Cost per mile depends on nature of process and the site.
4-44
-------
TABLE 4-27. EXAMPLE CALCULATION CASE: CONTROL COST ALTERNATIVES FOR
WET SCRUBBER ON DUCTED SOURCES
I. Basic design decisions
A. What are the specifications of the gas stream to be controlled?
1. . Maximum gas flow rate—40,000 acfm; 26,800 dscfm
2. Gas temperature and moisture content—250°F; 10% H20
3. Increase in gas flow rate due to evaporative cooling—none
4. Particulate concentration and size distribution—
4.0 gr/dscf, total particulate; estimated PM10 concentra-
tion =2.8 gr/dscf
B. What performance specifications are needed to achieve emission
reduction?
1. Efficiency—99.38 percent, total particulate; 95 percent,
PMio, estimated
2. Pressure drop—14 in. w.c. estimated
3. Liquid-to-gas ratio—10 gpm/1,000 acfm
C. What materials of construction are required?
1. Metal thickness due to pressure drop—3/16 in.
2. Carbon steel or stainless steel—carbon steel
D. What are the wastewater treatment and disposal requirements?
1. Chemicals and equipment for treatment—centralized system
2. Return to process—no
3. Landfill—yes
4. Surface impoundment—no
E. What are the restraints for retrofit?
1. Space limitations—none
2. Availability of water and surface impoundment—none
3. Minimum outage period—none
II. Construction/installation decisions
A. Who will install system?
1. Plant personnel —no
2. Contractor—yes
3. Overtime—no
4-45
-------
TABLE 4-27. (concluded)
B. Who is responsible for system shakedown/start-up?
1. Plant environmental staff—no
2. Plant personnel — no
3. Contractor—yes
III. Operation/maintenance decisions
A. What instrumentation is needed for reliable operation
1. Pressure drop meters—yes
2. Liquid fow meters—yes
3. Temperature indicators—yes
4. Recorders and control panel—yes
B. How will routine maintenance be performed?
1. Plant personnel--yes
2. Contractor—no
4-46
-------
TABLE 4-28. EXAMPLE CALCULATION CASE: CAPITAL EQUIPMENT AND O&M
EXPENDITURE ITEMS FOR A WET SCRUBBER ON A TYPICAL
DUCTED SOURCE
Capital Equipment
Scrubber
Separator
Quencher (precooler)
Radial tip fan
Fan motor
Motor starter
Fan damper(s)
Motor drive
Duct insulation
Scrubber pump
Sump pump and motor
Instrumentation and control panel
Clarifier
Vacuum filter
O&M Expenditures
Utilities
Water
Electricity
Materials
Chemicals
Spare parts
Labor
Operators
Supervision
Maintenance
Venturi
Included with venturi
Not needed
Yes
Dip proof
Included
Included
Included
Not needed
Included
Included
Included
Included
system
Included
system
with venturi
with venturi
with venturi
in water treatment
in water treatment
Make up water
Yes
Yes
Yes
Yes
Yes
Yes
4-47
-------
TABLE 4-29. EXAMPLE CALCULATION CASE: CAPITAL COSTS FOR A WET SCRUBBER
ON A TYPICAL DUCTED SOURCE
-P»
00
Component
Control device
Venturi scrubber
Automatic variable
Total
Auxiliary equipment
Ductwork
Radial tip fan
BLS Code 1147C
Fan motor
BLS Code 11730/403.99°
Magnetic starter
BLS Code 11750.781.05°
V-belt drive5
BLS Code 1145°
Fan outlet damper
CE Index
Total
Specifications
Includes venturi, separator, pumps,
and controls; carbon steel, 14 in. WP,
3/16 in. thickness, 1.3 adjustment
factor
Update factor: b 336.2 -=- 2,262 = 1.486
Carbon steel 50 fet. , 1/8" in. 2 elbows
38,000 acfm, static pressure = 16.4
Update factor: 358.9 -=- 234.4 = 1.531
150 hp, 600 rpm-motor
Update factor: 334.5 -=- 216.3 =
1.593 x 110.5 = 1.760
With circuit breaker, 150 hp
Update factor: 254.1 -=- 176.3 = 1.441
Standard
Update factor: 337.6 4- 213.7 = 1.580
27,000 dscfm, 16.4 in. static pressure
Update factor: 1.486
Capital
Dec. 1977
28,700
6,350
35,050
3,851
8,800
10,000
1,450
573
825
cost ($)
April 1985
42,650
9,435
52,085
5,722
13,474
17,600
2,089
905
1,226
41,016
Reference3
5-13, 5-14
5-13
4-16, 4-17
4-19, 4-22
4-60, 4-63
4-61
4-62, 4-68,
4-61
4-66
4-65
Wastewater treatment
Clarifier, vacuum filter, and controls
,^r^^
-------
TABLE 4-29. (continued)
-p*
10
Component
Specifications
Capital cost ($)
Dec. 1977 April 1985
costs
Installation—direct
costs
taxes (3 percent), freight (5 percent);
total (18 percent); multiplier
factor =0.18
Foundations and supports (4 percent),
erection and handling (50 percent),
electrical (8 percent), piping
(1 percent), insulation (2 percent),
and painting (2 percent); total
(67 percent); multiplier factor = 0.67
454,915
Reference
Continuous monitors
--flow meter
--pressure drop sensor
--chart/vendor
CE Index5
Total
TOTAL EQUIPMENT COSTS
Purchased equipment
Impeller, sensor, display, output
transmitter
With transmitter
Two per recorder
Update factor: 336.2 -=• 327.6 = 1.026
Control device, auxiliary equipment,
wastewater treatment, and continuous
monitors
Instruments and controls (10 percent),
740e
740e
l,420e
2,900 2,976
5,876
678,977
122,216
Quote from
vendor
Quote from
vendor
Quote from
vendor
3-11
3-11
3-11
-------
TABLE 4-29. (concluded)
en
o
Capital cost ($)
Component
Continuous monitors
(continued)
Specifications
Dec. 1977 April 1985
Reference
Installation indirect
cost
Total capital costs
Engineering and supervision (20 percent),
construction and field expenses
(20 percent), construction fee
(10 percent), start-up (1 percent),
performance test (1 percent),
contingencies (3 percent); total
(55 percent); multiplier factor = 0.55
373,437
3-11
1,629,500 (rounded)
All numbers indicate page numbers in Reference 1, except where noted otherwise.
Chemical Engineering Fabricated Equipment Index: April 1985 Index ' December 1977 index = update
factor.
Bureau of Labor Statistics Index; April 1985 Index; December 1977 index = update factor.
Value prorated for 40 percent of total system costs; referenced installed cost converted to capital
cost; December 1982 costs updated to April 1985 costs by Chemical Engineering Index.
Vendor quote obtained in February 1983; updated to April 1985 costs by C.E. index.
-------
TABLE 4-30. EXAMPLE CALCULATION CASE: ANNUALIZED COSTS AND COST-EFFECTIVENESS FOR A
WET SCRUBBER ON A TYPICAL DUCTED SOURCE
Component
Capital costs
--Sump pump
— Makeup water cost
--Water treatment
Operating labor costs
— Operating labor
--Supervisory labor
Maintenance cost
--Maintenance labor
--Materials
Specifications
10 hp, 8,000 hr/yr
0.50 gal/1,000 gal., $0.60/1,000 gal.
$2.16/1,000 gal., 400 gpm
2 hr/shift, $12.35/hr
15% of operating labor
1 hr/shift, $13.60/hr
Equal to maintenance labor costs
Annuali zed cost
April 1985 ($)
4,267
58
414,700
487,299
24,700
3,705
31,105
13,600
13,600
27,200
Reference3
3-17
Estimate
3-14
3-12
3-14, 3-12
3-12
Overhead
80% of total O&M costs
7
44,484
3-12
-------
TABLE 4-30. (concluded)
Component
Specifications
Annual ized cost
April 1985 ($)
Reference
Capital charges
— Administrative costs
— Property costs
— Insurance
—Capital recovery
Total annual ized costs
2% of capital costs
1% of capital costs
1% of capital costs
10 yr, 13% interest, CFR = 0.1843
32,590
16,295
16,295
300,317
365,497
Utilities, operating labor, total maintenance, 955,585
overhead, and capital charges
Total annual ized costs,
(rounded)
COST EFFECTIVENESS
Calculated emission reduction =
955,600
3-12
3-12
3-12
3-12
3-11
(2.8 gr/dscf)(26,770 dscf/min)(8,000 h/yr)(0. 95)(4. 285 xlO-6
= 2,440 tons/yr
Cost effectiveness = $955,600 yr/2,440 ton/yr = $392/ton of particulate.
All numbers indicate page numbers in Reference 1.
-------
TABLE 4-31. EXAMPLE CALCULATION CASE: CONTROL COST ALTERNATIVES FOR WET
SUPPRESSION OF PROCESS FUGITIVE EMISSIONS
I. Basic design decisions
A. What type wet suppression system will be used?
1. Water spray—yes
2. Water/surfactant spray—no
3. Micron-sized foam—no
4. Combination systm—no
B. What sources will be controlled? One primary, one secondary,
and one tertiary crusher; truck dump to primary crusher, two
screens, and six conveyor transfer points
C. What system layout will be used?
1. Centralized supply with headers for each source—yes
2. Individual systems for some sources
Note: process operates 40 hr/week, 48 week/yr, totaling
1,920 hr/yr; controls operate 80% of process time, or
1,536 hr/yr
II. Construction/installation decisions
A. Who will install system?
1. Contractor—yes
2. Plant personnel—no
III. Operational decisions
A. What is the water source?
1. Plant wells—yes
2. Local surface waters—no
3. City water system—no
B. Under what weather conditions will the system be needed?
1. Above freezing only-no
2. Below freezing—yes, requires winterization
C. How will routine maintenance be provided?
1. Plant personnel—yes
2. Maintenance contractor—no
4-53
-------
TABLE 4-32. EXAMPLE CALCULATION CASE: CAPITAL
EQUIPMENT AND O&M EXPENDITURE
ITEMS FOR WET SUPPRESSION OF
PROCESS FUGITIVE EMISSIONS
Capital Equipment
- Water spray systems
• Supply pumps--yes
• Nozzles—yes
• Piping (including winterization)—yes
• Control system—yes
Filtering units—yes
- Water/surfactant and foam systems only
• Air compressor—yes
• Mixing tank—yes
• Metering or proportioning unit—yes
• Surfactant storage area—yes
O&M Expenditures
- Utility costs
• Water—yes, $/l,000 gal.
• Electricity—yes, $/kWh
- Supplies
• Surfactant—yes
• Screens—no
- Labor
• Maintenance—192 hr/yr
• Operation—96 hr/yr
4-54
-------
TABLE 4-33. EXAMPLE CALCULATION CASE: COST ESTIMATION FOR
PROCESS FUGITIVE CONTROL
Type of equipment
Equipment Installation Total
cost ($) cost ($) cost ($)
CAPITAL COSTS3 'b
Wet suppression system
Water filter and flush
High pressure system for truck dump
Shelter house
Winterizationc
Total
Component
ANNUAL OPERATING COSTS
Utilities
24,520
2,970
4,630
4,280
3,640
40,040
33,830
350
2,290
640
3,710
40,820
_ f) ,ni£/V
58,350
3,320
6,920
4,920
7,350
80,860
Annual i zed
cost ($)
k
Electrical .power - 2,880 kWh/yjr_@
5.5
-------
TABLE 4-33. (concluded)
COST EFFECTIVENESS
Operating rate: 300 ton/hr ~)
Operating hours: 1,920 hr/yr /
Utilization: 80%
Calculated emissions reductions
Primary crusher: (29 ton/yr)(0.80) = 23
Secondary crusher: (173 ton/yr)(0.65) = 112
Tertiary crusher: (864 ton/yr)(0.5) = 432
Screens: (190 ton/yr)(0.5) = 95
Total = 662 ton/yr
Cost effectiveness = 552'ton/yr = $46/ton of Particulate
Reference for capital costs and units of operating materials, utilities,
and labor: Evans, R. J., Methods and Costs of Dust Control in Stone
Crushing Operations, PB-240 834, U.S. Bureau of Mines, 1C 8669,
January 1975.
Costs are updated from July 1974 to January 1984 using the CE Plant Cost
Index for Fabricated Equipment.
Estimated as 10% of other capital equipment.
Estimated average cost of electrical power for industrial users as of
January 1984 based on Energy Users.
8 MRI estimate.
Estimated hourly rate for a laborer in the minerals manufacturing indus-
try in January 1984 based on statistics in the Monthly Labor Review.
9 Costs updated from July 1974 to January 1984 using CE Plant Cost Index
for Pipes, Valves, and Fittings.
4-56
-------
TABLE 4-34. EXAMPLE CALCULATION CASE: COST AND COST EFFECTIVENESS
ESTIMATE FOR TYPICAL OPEN SOURCE CONTROL
This table lists the steps necessary to calculate the cost effective-
ness for two control alternatives for stabilizing unpaved travel surfaces.
Following the list of nine steps is an example problem illustrating the
calculations. Table 4-35 through 4-38 are referenced in the calculations
in Table 4-34.
Step 1 - Specify Desired Average Control Efficiency (e.g., 50, 75,
or 90%)
Step 2 - Specify Basic Vehicle, Road and Climatological Parameters
for the Particular Road of Concern
Required vehicle characteristics include:
1. Average Daily Traffic (ADT)-This is the number of vehicles using
the road regardless of direction of travel (e.g., on a two lane road in an
iron and steel plant, 100 vehicles in one direction, and 100 in the other
direction during a single day yields 200 ADT);
2. Average vehicle weight in short tons;
3. Average number of vehicle wheels; and
4. Average vehicle speed in mph.
Required road characteristics include:
1. Actual length of roadway to be controlled in miles;
2. Width of road to be controlled;
3. Silt content (in percent)-For an existing road, these values should
be measured; however, for a proposed plant, average values shown in AP^^
can be used; "2-
4. Surface loading (for paved roads) in Ib/mile - This is the total
loading on all traveled lanes rather than the average lane loading; and
5. Bearing strength of the road-At this time, just a visual estimate
of low, moderate, or high is required.
Required Climatological characteristics (applicable only to watering
of unpaved roads): Potential evaporation in mm/hr—the value depends on
both the location and the month of concern. Control efficiency data in
this report for watering unpaved roads assume a location in Detroit,
Michigan, in the summer.
Step 3 - Calculate the Uncontrolled Annual Emission Rate as the
Product of the Emission Factor and the Source Extent
The emission factor (E) should be calculated using the equations from
4-57
-------
TABLE 4-34. (continued)
The annual source extent (SE) is calculated as 365 x ADT x average
one way trip distance.
Step 4 - Consult the Appropriate Control Program Design Table to
Determine the Time Between Applications and the Application Intensity
Select the appropriate table
Table
containing
Control technique information
Coherex® applied to unpaved roads Table 4-35
Petro Tac applied to unpaved roads Table 4-26
Verify that the vehicle and road characteristics listed in Step 2 are
similar to those listed in the footnotes of the selected table. If they
are significantly different, the table cannot be used.
Step 5 - Calculate the Number of Annual Applications Necessary by
Dividing 365 by the Days Between Application (from Step 4)
Step 6 - Calculate the Number of Treated Miles Per Year by Multiplying
the Actual Miles of Road to be Controlled (from Step 2) by the Number of
Annual Applications (from Step 5)
Step 7 - Consult the Appropriate Program Implementation Alternatives
Table and Select the Desired Program Implementation Plan
Table
containing
Control technique information
Coherex® applied to unpaved roads Table 4-37
Petro Tac applied to unpaved roads Table 4-38
Step 8 - Calculate Total Annual Cost by Annualizing Capital Costs and
Adding to Annual Operation and Maintenance Costs
To annualize capital investment, the capital cost is multiplied by a
capital recovery factor which is calculated as follows:
CRF = [1(1 -H)n] / [(1 + i)n -1]
where
CRF = capital recovery factor
i = annual interest rate fraction
n = number of payment years
4-58
-------
TABLE 4-34. (continued)
Scale total annual cost by ratio of actual road width in feet
divided by 40 ft.
Step 9 - Calculate Cost Effectiveness by Dividing Total Annual Costs
(from Step 8) by the Annual Uncontrolled Emission Rate (from Step 3) and
by Desired Control Efficiency Fraction (from Step 1)
Example calculation. The following is an example cost-effectiveness
calculation for controlling PM-10 using Coherex® on an unpaved road in a
Step 1 - Specify Desired Average Control Efficiency
Desired average control efficiency = 90%
Step 2 - Specify Basic Vehicle, Road, and Climatological Parameters
for the Particular Road of Concern
Required vehicle characteristics:
1. Average daily traffic = 100 vehicles per day;
2. Average vehicle weight = 40 ST;
3. Average number of vehicle wheels = 6; and
4. Average vehicle speed = 20 mph
Required road characteristics
1. Actual length of roadway to be controlled =6.3 miles;
2. Width of roadway = 30 ft;
3. Silt content = 7.3%
4. Bearing strength of road = moderate
Step 3 - Calculate Uncontrolled Annual Emission Rate as the Product
of the Emission Factor and the Source Extent
/
E = emission factor
k = O..45r for PM-10 (as per Appendix C)
s = 7.3 percent (given in Step 2)
S = 20 mph (given in Step 2)
W = 40 ST (given in Step 2)
w = 6 (given in Step 2)
p = 140 (as per Figure 11.2-1-1 in Ap-42 Supplement 14 for
Detroit, Michigan)
4-59
-------
TABLE 4-34. (continued)
E = 4.98 Ib/VMT
SE = 365 x ADT x average one-way trip distance
cc - ics days v inn vehicles v 6.3 miles
SE - 365 yet? x 10° day x
SE = 115,000 VMT/year
Emission rate = E x SE
Emission rate = 4.98 Ib/VMT x 115,000 VMT/year x l short ton
Emission rate = 286 tons of PM10 per year
Step 4 - Consult the Appropriate Control Program Design Table To
Determine the Times Between Applications and the Application Intensify
Use Table 4-35.
The vehicle and road characteristics listed in Step 2 are
similar to those in the footnotes of Table 2-1.
From Table 4-35:
Application intensity = 0.83 gal. of 20% solution/yd2
(initial application)
=1.0 gal. of 12% solution/yd2
(reapplications)
Application frequency = once every 47 days
Step 5 - Calculate the Number of Annual Applications Necessary by
Dividing 365 by the Days Between Applications (from Step 4)
No. of annual applications = ^5 = 7.77 applications
T1/ year
Step 6 - Calculate the Number of Treated Miles Per Year by Multiplying
the Actual Miles of Road to Be Controlled (from Step 2) by the Number of
Annual Applications (from Step 5)
No. of treated miles per year = 6.3 miles x 7.77 app1^tlons .
= 49 treated miles/year
4-60
-------
TABLE 4-34. (continued)
Step 7 - Consult the Appropriate Program Implementation Alternatives
Table and Select the Desired Program Implementation Plan
From Table 4-37, the following implementation plan and associated
costs are anticipated:
Cost
Capital Unit cost
invest- $/Treated$/Actual
Selected Alternative ment, $ mile mile
1. Purchase Coherex® and ship in truck 4,650
tanker
2. Store in newly purchased storage 30,000
tank
3. Prepare road with plant owned 630
grader
4. Pump water from river or lake 5,000
5. Apply chemical with plant owned 70,000
application truck (includes labor
to pump water and Coherex® and
apply solution)
105,000 4,785 630
Step 8 - Calculate Total Annual Cost by Annualizing Capital Costs
and Adding to Annual Operation and Maintenance Costs
Calculate annual capital investment (PI) = capital investment x CRF
CRF = [i(l+i)n]/[(l-H)n-l]
CRF = capital recovery factor
i = 0.15
n = 10 years
CRF = 0.199252
PI = 105,000 x 0.199252 = $20,900/year
Calculate annual operation and maintenance costs (MO)
MO = $4,785/treated mile x 49 treated miles/year +
$630/actual mile x 6.3
= $238,000/year
4-61
-------
TABLE 4-34. (concluded)
Calculate total cost (D) = PI + MO
D = $20,900/year + $238,000/year
= $258,900/year
Scale total cost by actual road width:
Actual total cost for a 30-ft wide road = $258,900/year x
= $194,200/year
Step 9 - Calculate Cost Effectiveness by Dividing Total Annual Costs
(from~STep 8) by the Annual Uncontrolled Emission Rate (from Step 3) and
by the Desired Control Efficiency Fraction (from Step 1)
Cost effectiveness = •?
$194,200/year
ZB6ST/year x 0.9
= $754/short ton of PM10 reduced
4-62
-------
TABLE 4-35. ALTERNATIVE CONTROL PROGRAM DESIGN FOR COHEREX® APPLIED
TO TRAVEL SURFACES
Average
percent
control
desired
50
75
90
k
Particle size
TP
IP
PM-10
TP
IP
PM-10
TP
IP
PM-10
Vehicle
passes between
applications
41,800
26,200
23,300
19,600
12,900
11,600
6,200
4,900
4,650
as
100
418
262
233
196
129
116
62
49
47
Days between
applications
a function of
300
139
87
78
65
43
39
21
16
16
ADTC
500
84
52
47
39
26
23
12
10
9
Calculated time and vehicle passes between application are based on the
following conditions:
Suppressant application:
• 3.7 L of 20% solution/m2 (0.83 gal. of 20% solution/yd2); initial
application
• 4.5 L of 12% solution/m2 (1.0 gal. of 12% solution/yd2); reappli-
cations
Vehicular traffic:
• Average weight--39 Mg (43 tons)
• Average wheels--6
• Average speed--29 km/hr (20 mph)
Road structure: bearing strength—low to moderate
' TP = particles of all sizes.
IP = particles < 15 umA.
PM-10 = particles < 10 umA.
' For reapplications that span time periods greater than 365 days, the
effects of the freeze-thaw cycle are not incorporated in the reported
values.
4-63
-------
TABLE 4-36. ALTERNATIVE CONTROL PROGRAM DESIGN FOR PETRO TAG APPLIED
TO UNPAVED TRAVEL SURFACES3
Average
percent
control
desired
50
75
90
k
Particle size
TP
IP
PM-10
TP
IP
PM-10
TP
IP
PM-10
Vehicle
passes between
applications
107,000
80,600
92,000
44,700
41,900
47,800
7,250
18,600
21,200
as a
100
1,070
806
920
447
419
478
72
186
212
Days between
applications
function of
300
357
269
307
149
140
159
24
62
71
ADTC
500
214
161
184
89
84
96
14
37
42
Calculated time and vehicle passes between application are based on the
following conditions:
Suppressant application: 3.2 L of 20% solution/m2 (0.7 gal.
20% solution/yd2); each application
Vehicular traffic:
• Average weight — 27 Mg (30 tons)
• Average wheels--9.2
• Average speed — 22 km/h (15 mph)
Road structure: bearing strength — low to moderate
of
TP
IP
PM-10
particles of all sizes.
particles < 15 [jmA.
particles < 10 umA.
For reappli cations that span time periods greater than 365 days, the
effects of the freeze-thaw cycle are not incorporated in the reported
values.
4-64
-------
TABLE 4-37. IDENTIFICATION AND COST ESTIMATION OF COHEREX*
CONTROL ALTERNATIVES
Program implementation alternatives
Cost
I. Purchase and ship Coherex®
A. Ship in rail car tanker (11,000-22,000
gal/tanker)
B. Ship in truck tanker (4,000-6,000
gal/tanker)
C. Ship in drums via truck (55 gal/drum)
II. Store Coherex®
A. Store on plant property
1. In new storage tank
2. In existing storage tank
a. Needs refurbishing
b. Needs no refurbishing
3. In railcar tanker
a. Own railcar
b. Pay demurrage
4. In truck tanker
a. Own truck
b. Pay demurrage
5. In drums
B. Store in contractor tanks
III. Prepare road
A. Use plant-owned grader to minimize
ruts and low spots
B. Rent contractor grader
C. Perform no road preparation
IV. Mix Coherex® and water in application
truck
A. Load Coherex® into spray truck
1. Pump Coherex® from storage tank
or drums into application truck
2. Pour Coherex® from drums into
application truck, using
forklift
$4,650/treated mile
$4,650/treated mile
$7,040/treated mile
$30,000 capital
$5,400 capital
-0-
-0-
$20, $30, $60/treated
mile
-0-
$70/treated mile
-0-
$140/treated mile
$630/actual mile
$l,200/actual mile
-0-
Tank - 0 (included in
price of storage tank)
Drums - $1,000 capital
$l,000/treated mile
4-65
-------
TABLE 4-37. (concluded)
Program implementation alternatives
Cost
B. Load water into application truck
1. Pump from river or lake
2. Take from city water line
V. Apply Coherex® solution via surface
spraying
A. Use plant owned application truck
B. Rent contractor application truck
$5,000 capital
$40/treated mile
$70,000 capital + $135/
treated mile for tank or
$270/treated mile for
drums
Tank - $500/treated mile
Drums - $l,000/treated
mile
4-66
-------
TABLE 4-38. IDENTIFICATION AND COST ESTIMATION OF PETRO TAC
CONTROL ALTERNATIVES
Program implementation alternatives
Cost
II.
Purchase and ship Petro Tac ^
A. Ship in truck tanker (4,000-6,000 gal/
tanker)
B. Ship in drums via truck (55 gal/drum)
Store Petro Tac
A. Store on plant property
1.
2.
3.
4.
In new storage tank
In existing storage tank
a. Needs refurbishing
b. Needs no refurbishing
In rail car tanker
a. Own rail car
b. Pay demurrage
B.
In truck tanker
a. Own truck
b. Pay demurrage
5. In drums
Store in contractor tanks
III. Prepare road
A. Use plant owned grader to minimize
ruts and low spots
B. Rent contractor grader
C. Perform no road preparation
IV. Mix Petro Tac and water in application
truck
A. Load Petro Tac into spray truck
1.
2.
Pump Petro Tac from storage tank
or drums into application truck
B.
Pour Petro Tac from drums into
application truck, generally using
forklift
Load water into application truck
1. Pump from river or lake
2. Take from city water line
$5,400/treated mile
$ll,500/treated mile
$30,000 capital
$5,400 capital
-0-
-0-
$20, $30, $60/treated
mile'
-0-
$70/treated mile
-0-
$140/treated mile
$630/actual mile
$l,200/actual mile
-0-
Tank - 0 (included in
price of storage tank)
Drums - $1,000 capital
$l,000/treated mile
$5,000 capital
$40/treated mile
4-67
-------
TABLE 4-38. (concluded)
Program implementation alternatives
Cost
V. Apply Petro Tac solution via surface
spraying
A. Use plant-owned application truck
B. Rent contractor application truck
$70,000 capital + $1357
treated mile for tank
or $270/treated mile
for drums
Tank - $500/treated mile
Drums - $l,000/treated
mile
4-68
-------
O
a
LT)
00
n
O
00
O
1,200 IIjIIJI1I
! NOTE: FOB FACTORY. INSTRUMENTS AND CONTROLS AND TAXES NOT INCLUDED.
1,000
800
600
400
200
100
80
60
40
20
10 L
PRESSURE DROP, kPa (inches w.c.)
CURVE 1 15 (60)
CURVE 2 10 (40)
CURVE 3 5 (20)
I I
J I
(2?)
(8) (ft) (8%(1?8>
(2?8)
(320) (640) (353)
EXHAUST GAS RATE, m3/s (lo3 ft3/m1n)
Figure 4-1. Cost of venturi scrubbers, unlined throat
with carbon steel construction.
4-69
-------
C/7
in
CO
ce
Q_
CAPITAL COST
ANNUALIZED COST
PRESSURE DROP, kPa (inches w.c.)
CURVE 1 15 (60)
CURVE 2 10 (40)
CURVE 3 5 (20)
60 -
40
I I
(1?) (42) (84) (85) (1?8
3QQ 400
(640) (850)
EXHAUST GAS RATE, m3/s (103 ft3/min)
Figure 4-2. Capital and annualized costs of venturi scrubbers
with carbon steel construction.
4-70
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20,000
10,000
8,000
6,000
4,000 •
3,000
10 2,000
O
o
in
CO
1,000
800
600
400
300
200
100
I I I
I I
CAPITAL COST
... ANNUALIZED COST
PRESSURE DROP, kPa (inches w.c.)
CURVE 1 15 (60)
CURVE 2 10 (40)
CURVE 3 5 (20)
I I
J 1
(2?,
(450) (616) (850)
EXHAUST GAS RATE, m3/s (103 ft3/min)
Figure 4-3. Capital and annualized costs of venturi scrubbers
with stainless steel construction.
4-71
-------
O
a
m
CO
a.
ef.
O
CJ
10,000
8,000
6,000
4,000
2,000
1,000
800
600
400
200
100
l I I
NOTE: THERMALLY INSULATED. FOB FACTORY. INSTRUMENTS
AND CONTROLS AND TAXES NOT INCLUDED.
FOR DUST
HAVING
HIGH
RESISTIVITY
FOR OUST
HAVING
.MOOERATE-
TO-LOW-
RESISTIVITY
SCA = mV(1.000 m3/m1n) (ft2/U,000 ft3/m1n])
n = COLLECTION EFFICIENCY
I i I
(2?)
(420) (640) (850)
EXHAUST GAS RATE, mJ/s (103 ft3/m1n)
Figure 4-4. Cost of electrostatic precipitators with
carbon steel construction.
4-72
-------
o
a
oo
en
OS
a.
-------
4,000
t/i
ex.
in
oo
OL
Q.
-------
12,000
o
o
IT)
CD
o:
CL.
10,000
8,000
6,000
4,000
3,000
2,000
1,000
800
600
400
300
200
100
CAPITAL COSTS
ANNUALIZED COSTS
TYPE OF CLEANING MECHANISM
CURVE 1 REVERSE AIR
CURVE 2 SHAKER
CURVE 3 PULSE JET
AIR-TO-CLOTH RATIO m/min (ft/min)
CURVE 1 0.46 to 1.0 (1.5 to 3.3)
CURVE 2 0.61 to 1.0 (2.0 to 3.3)
CURVE 3 2.12 to 1.0 (3.3 to 7.0)
BAG MATERIAL
CURVE 1 NYLON
CURVE 2 NYLON
CURVE 3 NOMEX
J
EXHAUST GAS RATE, m3/s (103 ft3/min)
Figure 4-7. Capital and annualized costs of fabric filters
with stainless steel construction.
4-75
-------
IT)
CO
ac.
Q.
00
O
10,000
8,000
6,000
4,000
2,000
1,000
800
600
400
200
100
80
60
i r
CAPITAL COSTS
ANNUALIZED COSTS
TYPE OF CLEANING MECHANISM
CURVE 1 REVERSE AIR
CURVE 2 SHAKER
CURVE 3 PULSE JET
AIR-TO-CLOTH RATIO m/min (ft/min)
CURVE 1 0.46 to 1.0 (1.5 to 3.3)
CURVE 2 0.61 to 1.0 (2.0 to 3.3)
CURVE 3 2.12 to 1.0 (3.3 to 7.0)
BAG MATERIAL
CURVE 1 NYLON
CURVE 2 NYLON
CURVE 3 NOMEX
10 20 30 40 50 100
(21) (42) (64) (85) (110) (210)
EXHAUST GAS RATE, m3/s (103 ft3/min)
(88
) (640)
Figure 4-8. Capital and annualized costs of fabric filters
with carbon steel construction.
4-76
-------
IT)
CO
00
O
1,000
800
600
400
200
100
80
60
40
20
10
8
1 I I
CAPITAL COSTS
—-ANNUALIZED COSTS
NOTE: COST OF'DUCT INCLUDES ONE ELBOW.
I i I
(2?,
(12) (8?) (1
(2?8,
5) (850)
EXHAUST GAS RATE, m3/s (103 ft3/min)
Figure 4-9. Capital and annualized costs of fans and
30.5 m (100 ft) length of duct.
4-77
-------
00
o
a
uo
CO
o>
a:
a.
00
o
ANNUALIZED COST BASED ON
8,700 h/yr OPERATION
10
EXHAUST GAS RATE, m3/s (103 ft3/min)
Figure 4-10. Capital and annualized costs of fan driver
for various head pressures.
4-78
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REFERENCES FOR SECTION 4
1. Neveril, R. B. Capital and Operating Costs of Selected Air Pollution
Control Systems. EPA 450/5-80-002. U. S. Environmental Protection
Agency, Research Triangle Park, December 1978.
2. W. Vatave-6 and R. Neveril. Estimating Costs of Air Pollution Systems.
Part I: Parameters for Sizing Systems. Chem. Eng., p. 165-168,
October 6, 1980.
3. W. Vatavek and R. Neveril. Estimating Costs of Air Pollution
Systems. Part II: Factors for Estimating Capital and Operating
Costs. Chem. Eng.. p. 157-162, November 3, 1980.
4. W. Vatavek and R. Neveril. Estimating Costs of Air Pollution
Systems. Part III: Estimating the Size and Cost of Pollutant
Capture Hoods. Chem. Eng., p. 111-715, December 1, 1980.
5. W. Vatavek and R. Neveril. Estimating the Costs of Air Pollution Sys-
tems. Part IV: Estimating the Size and Cost of Ductwork. Chem. Eng.,
p. 71-73, December 29, 1980.
6. W. Vatavek and R. Neveril. Estimating the Costs of Air Pollution
Systems. Part V: Estimating the Size and Cost of Gas Conditioners.
Chem. Eng.. p. 127-132, January 26, 1981.
7. W. Vatavek and R. Neveril. Estimating the Costs of Air Pollution
Systems. Part VI: Estimating Costs of Dust-Removal and Water-
Handling Equipment. Chem. Eng., p. 223-228, March 23, 1981.
8. W. Vatavek and R. Neveril. Estimating the Costs of Air Pollution
Systems. Part VII: Estimating Costs of Fans and Accessories.
Chem. Eng., p. 171-177, May 18, 1981.
9. W. Vatavek and R. Neveril/ Estimating the Costs of Air Pollution
Systems. Part VIII: Estimating Costs of Exhaust Stacks. Chem. Eng.,
p. 129-130, June 15, 1981.
10. W. Vatavek and R. Neveril. Estimating the Costs of Air Pollution
Systems. Part IX: Costs of Electrostatic Precipitators. Chem. Eng.,
p. 139-140, September 7, 1981.
11. W. Vatavek and R. Neveril. Estimating the Costs of Air Pollution
Systems. Part X: Estimating Size and Cost of Venturi Scrubbers.
Chem. Eng., p. 93-96, November 30, 1981.
12. W. Vatavek and R. Neveril. Estimating the Costs of Air Pollution
Systems. Part XI: Estimating Size and Cost of Baghouses. Chem. Eng.,
p. 153-158, March 22, 1982.
4-79
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13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
W. Vatavek and R. Neveril. Estimating the Costs of Air Pollution
Systems. Part XII: Estimating the Size and Cost of Incinerators.
Chem. Eng. . p. 129-132, July 12, 1982.
W. Vatavek and R. Neveril. Estimating th'e Costs of Air Pollution
Systems. Part XIII: Costs of Gas Absorbers. Chem. Eng., p. 135-136,
October 4, 1982.
W. Vatavek and R. Neveril.
Systems. Part XIV: Costs
January 24, 1983.
Estimating the Costs of Air Pollution
of Carbon Adsorbers. Chem. Eng., p. 131-132,
W. Vatavek and R. Neveril. Estimating the Costs of Air Pollution Sys-
tems. Part XV: Costs of Flares. Chem. Eng., p. 89-90, February 21,
1983. pp. 89-90.
W. Vatavek and R. Neveril. Estimating the Costs of Air Pollution Sys-
tems. Part XVI: Costs of Refrigeration Systems. Chem. Eng., p. 95-98,
May 16, 1983.
W. Vatavek and R. Neveril. Estimating the Costs
Systems. Part XVII: Particle Emissions Control.
April 2, 1984.
of Air Pollution
Chem. Eng.. p. 97-99,
W. Vatavek and R. Neveril. Estimating the Costs of Air Pollution Sys-
tems. Part XVIII: Gaseous Emissions Control. Chem. Eng., p. 95-98,
April 30, 1984.
U.S. Environmental Protection Agency. Control Techniques for Particu-
late Emissions From Stationary Sources—Volume 1. EPA-450/3-81-005a,
Emission Standards and Engineering Division, Research Triangle Park,
NC, September 1982.
U.S. Environmental Protection Agency. Development of Air Pollution
Control Cost Functions for the Integrated Iron and Steel Industry.
EPA-450/1-80-001, Research Triangle Park, NC, July 1979.
Cowherd, C. , et al. Identification, Assessment, and Control of Fugi-
tive Particulate Emissions. Draft Final Report, EPA Contract No.
68-02-3922, Midwest Research Institute, Kansas City, MO, April 1985.
Cuscino, T. , Jr. Cost Estimates For Selected Fugitive Dust Controls
Applied to Unpaved and Paved Roads In Iron and Steel Plants. Final
Report. U. S. Environmental Protection Agency, Region V, Chicago, IL,
April 1984.
4-80
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SECTION 5.0
METHODS OF COMPLIANCE DETERMINATION
Once a specific PM10 control strategy has been developed and imple-
mented, it becomes necessary for either the control agency or industrial
concern to assure that it is achieving the desired level of control. As
stated previously, the control efficiency actually attained by a particular
technique depends on its proper implementation. This section will discuss
methods for determining compliance with various regulatory requirements re-
lating to PM10 control strategies. These methods include source testing,
visual observations, and other techniques such as recordkeeping of key
control parameters.
5.1 SOURCE TESTING METHODS FOR PM10
5.1.1 Ducted Source Testing Methods
As part of the SIP process, the promulgation of a revised NAAQS for
PM10 will necessitate the development of appropriate size-specific particu-
late emission standards for ducted sources. In order to determine compli-
ance with these standards (as well as assist in their development), an
appropriate methodology must be used to determine the emission rate of PM10.
At present, no standard technique has been developed specifically for
the measurement of PM10 from ducted sources. However, interim guidelines
have been prepared to assist regulatory and industry personnel in conduct-
ing this determination until such time that a standard reference test method
is published by EPA. These guidelines are presented in Appendix C of Ref-
erence 1 which will be described below.1
5-1
-------
Since PMio is defined as participate matter equal to or less than 10 urn
in aerodynamic diameter, some type of inertial sizing technique is most ap-
propriate for use in source testing. Of the available instruments, either
a multistage cascade impactor or a single-stage cyclone collector would be
suitable for this purpose. Cyclones offer the advantage of low particle
bounce and thus are generally preferred over impactors, with the stipulation
that an empirical calibration be conducted prior to use in the field. Sam-
pling trains which incorporate an inertial sizing device are illustrated in
Figures 5-1 and 5-2 for noncondensible and condensible particulate emissions,
respectively.1
The use of an inertial sizing technique does have the inherent problem
that isokinetic sampling cannot usually be conducted in the traditional
sense (i.e., EPA Method 5). This is due to the fact that inertial devices
must be operated at a constant flow rate to maintain their size fractiona-
tion characteristics (i.e., cut-points). Thus, adjustment of the flow rate
cannot generally be conducted to achieve isokinetic sampling conditions
during a multipoint traverse of the duct.
There are a number of approaches which have been proposed to solve the
above sampling problem. These approaches include: the Simulated Method 5
(SIM-5) technique; the emission gas recycle (EGR) system; and a method based
on the sampling protocol developed for the IP characterization program.2 4
Each will be discussed below.
In the SIM-5 technique, a standard fixed-flow sampler is used with
anisokinetic sampling errors kept within reasonable limits by setting
velocity criteria on a point-by-point basis.2 Sampling nozzles are changed,
as necessary, during testing to match the sampling velocity to the duct
velocity within ±20% of isokinetic conditions. Since the flow rate cannot
be changed, the duration of sampling is varied from point to point to be
proportional to the local velocity. The sample volume obtained is propor-
tional to the total volumetric flow through the area represented by each
sampling point.2 The SIM-5 method involves a rather complex calculation
procedure and thus would be fairly difficult to implement routinely.
5-2
-------
HEATED PROBE
IP
SAMPLER
FILTER
HOLDER
IMP1NGER TRAIN OPTIONAL:
MAY BE REPLACED BY AN
EQUIVALENT CONDENSER
IMPINGERS IN ICE BATH
CHECK
VALVE
MANOMETER
DRY TEST METER AIR TIGHT PUMP
41S1-44SA
Figure 5-1. PM10 particulate sampling train for noncondensible
particulate (Modified EPA Method 5 train).1
5-3
-------
HEATED PROBE
\
IP
SAMPLER
IMPINGER TRAIN OPTIONAL:
MAY BE REPLACED BY AN
EQUIVALENT CONDENSER
HEATED
AREA FILTER HOLDER
THERMOMETER
CHECK
VALVE
IMPINGERS IN ICE BATH
MAIN VACUUM LINE
VALVE
Q
MANOMETER DRY TEST METER AIR TIGHT PUMP
41J1-64SB
Figure 5-2. PM10 participate sampling train for condensible and
noncondensible particulate (Modified EPA Method 5
train).1
5-4
-------
The EGR system, currently under evaluation by EPA, involves the incor-
poration of a recirculation loop in the sampling train to augment the sample
flow through an inertial sizing device.3 A fixed flow is thus maintained
through the inertial classifier while allowing the sampling rate to be
varied from point-to-point in the traditional (i.e., Method 5) manner. This
system is by far the easiest of the three methods to implement. A diagram
of the current EGR system is shown in Figure 5-3. 3
Lastly, a method based on the protocol originally developed for the
EPA's inhalable particulate (IP) research program could also be used for
conducting PM1() compliance tests.4'5 In this method, a series of single-
point samples are collected using a standard inertial classifier and ap-
propriately sized nozzles which are subsequently combined to synthesize a
complete traverse. It is currently recommended that a four-point grid be
used with a sample collected /rom each grid location to make up a single
test run (Figure 5-4). x Triplicate runs are to be conducted for each duct
tested to obtain a total of 12 individual samples. This technique has been
found to be extremely laborous, time-consuming, and difficult to perform on
a routine basis.
Finally, additional guidelines on the selection and operation of
samplers and sampling trains can be found in Reference 1. The reader is
directed to these guidelines for supplementary details on this subject.
5.1.2 Fugitive Source Testing Methods
Although a number of different techniques have been developed over the
years to determine mass emissions from fugitive sources, the only reference
method which has been published by EPA is Method 14 for Primary Aluminum
Potroom Roof Monitors.6 This method involves the installation of a sampling
manifold containing large-diameter nozzles. A large volume of effluent is
collected by the system from the roof monitor(s) and subsequently trans-
ported to ground-level through a duct. A blower connected to the duct is
used to extract and exhaust the sample flow. Standard source sampling tech-
niques (i.e., Method ISA or 13B) are then used to determine appropriate
mass emission rates from the potroom.
5-5
-------
RECYCLE
LINE
PI TOT TUBE
EGR PROBE ASSEMBLY
1 U- 1
=3 ._ ,.„. | I j
U SAMPLING •"" •' — —
DEVICE
SAMPLE
,.
INLET
•EXHAUST
SEA LSO PUMP
DRY GAS METER
Figure 5-3. Schematic of the Emission Gas Recycle (EGR)
sampling train.3
5-6
-------
1
a/4
b/4
i
Figure 5-4. Recommended sampling points for circular and square
or rectangular ducts.1
5-7
-------
Since traditional source testing methods are used to determine mass
emissions from potroom roof monitors, there is no reason why one of the
methods discussed in Section 5.1.1 above could not also be used to deter-
mine the emissions of PM10 from this source as well. However, as would be
the case for any ducted source, similar limitations to those discussed
previously regarding the methodology to be used would also apply to this
particular application.
5.2 METHODS FOR DETERMINING VISIBLE EMISSIONS
5.2.1 Federal Reading Methods
As a compliance tool, the determination of visible emissions (VE) has
a long history of application to stationary sources. At the federal level,
use of VE as a compliance tool is reflected in the specification of three
methods:
Method 9 - Visual determination of the opacity of emissions from
stationary sources.
(Modified) Method 9 - For basic oxygen furnace processes.
Method 22 - Visual determination of fugitive emissions from
material processing sources.
For compliance purposes, Tables 5-1 to 5-3 summarize the major features of
each visual observation method.
Method 9 (M9) is the most familiar of the observation methods. It is
widely used in the evaluation of stack emissions. Important advantages of
M9 include:7
5-8
-------
TABLE 5-1. SUMMARY OF EPA METHOD 9 REQUIREMENTS (M9)
Reader Position/Techniques
Sun must be in 140° sector behind the reader.
Plume direction should be as near perpendicular to
reader line of sight as possible.
Plume should be read at point of greatest opacity, ex-
cluding condensed water vapor.
Only one plume thickness should be read.
Individual opacity observations taken each 15 sec, re-
corded to the nearest 5% opacity.
Data Reduction
6-min time-average consisting of 24 consecutive 15-sec
readings.
Certification
Based on results of 25 white and 25 black plumes read
consecutively with the following error margins:
- No individual reading with error > 15% opacity.
- Average error over set of 25 readings < 7.5% opacity
(black or white plumes)
- Certification is valid for period of 6 months.
- Smoke generator must meet given specifications.
5-9
-------
TABLE 5-2. SUMMARY OF MODIFIED EPA METHOD 9 FOR BASIC
OXYGEN PROCESS FURNACES (MM9)
Reader Position/Techniques (Differences from Method 9)
Plume considered to consist of aggregate of emissions
from given building opening.
Observations taken from minimum of three steel pro-
duction cycles.
Data Reduction
3-min time-average consisting of 12 consecutive 15-sec
readings.
Certification (Same as Method 9)
5-10
-------
TABLE 5-3. SUMMARY OF EPA METHOD 22 REQUIREMENTS (M22)
Reader Position/Techniques
For outdoor locations sun must not be directly in ob-
servers eyes.
For indoor location proper application requires illumi-
nation > 100 lux (10-ft candles). Determination re-
quires light meter (50-200 lux range).
Observer position > 15 ft, < 0.25 mi.
Continuous observation for visible emissions regardless
of level. Period of observation > 6 min, not to exceed
15-20 min without rest break. Break > 5 min ^ 10 min.
Method requires two stop watches (unit division at
least 0.5 sec).
Stopwatch 1 - used to record duration of observation
period.
Stopwatch 2 - used to record duration of visible emis-
sions.
Data Reduction
Comparison of duration of visible emissions (stopwatch
2) to total observation period (stopwatch 1) according
to applicable regulations.
Certification
No specific requirements.
5-11
-------
M9 is detailed and formally promulgated.
M9 includes opacity observation procedures, data reduction methods,
and certification requirements.
M9 is consistent with New Source Performance Standards (NSPS)
that limit opacity based on a 6-min average.
M9 has supporting data on the accuracy of the method which should
be considered in determining possible violations.
Disadvantages of M9 are:
M9 is not compatible with time exemption regulations.
M9 is not suitable for evaluation of some intermittent emissions.
To determine compliance with Basic Oxygen Process Furnaces (BOPF) shop
roof monitor standards, certain modifications have been made to M9.8 Table
5-2 summarizes the primary method changes. It is important to note that
for this determination VE observers should position themselves to read
across the shortest dimension of the roof monitor rather than through the
long dimension from the end of the monitor. The latter position would re-
sult in a high bias in opacity determinations.8
The third EPA reading method, Method 22 (M22), is specified as appro-
priate for determining fugitive emissions from materials processing sources.9
In this method, sources of concern include emissions that:
1. Escape capture by process equipment exhaust hoods;
2. Are emitted during materials transfer;
5-12
-------
3. Are emitted from buildings housing material; and
4. Are emitted directly from process equipment.
M22 is one example of time-aggregating opacity observations. This
method uses continuous observation based on the comparison of emission time
(i.e., accumulated time with observed opacity £ 5%) to total observation
time.
5.2.2 Other Reading Methods
None of the previously discussed federal methods are directed specif-
ically at the evaluation of VE from open sources. However, based in part
on federal procedures, the State of Tennessee has developed a method (TVEE
Method 1) for evaluating VE from roads and parking lots.10 The following
discussion focuses on TVEE Method 1 (Ml) comparing it to the federal methods
in the technical areas: (1) reader position/techniques; and (2) data re-
duction/evaluation procedures. Table 5-4 summarizes the relevant features
of TVEE Ml.
5.2.1.1 Reader Position/Techniques—
As indicated in Table 5-4, TVEE Method 1 adopts the EPA Method 9 (M9)
criterion for observer position relative to the sun (140-degree sector
behind the reader). Ml specifies an observer location of 15 ft from the
source; that is the minimum distance called for in EPA Method 22 (M22).11
In most cases, this distance should allow an unobstructed view, and at the
same time meet observer safety requirements.
Ml also specifies that the plume be read at ~ 4 ft directly above the
emitting surface. This specification presumably results from field experi-
ments conducted to support the method. It is probably intended to represent
the point (i.e., location) of maximum opacity as read in M9. While there is
no quantitative supporting evidence, it seems likely that the height and lo-
cation of maximum opacity relative to a passing vehicle will vary depending
upon ambient factors (wind speed and direction) as well as vehicle type and
speed.
5-13
-------
TABLE 5-4. SUMMARY OF TVEE METHOD 1 REQUIREMENTS (Ml)
Reader Position/Techniques
Sun in 140° sector behind the reader.
Observer position ~ 15 ft from source.
Observer line of sight should be as perpendicular as
possible to both plume and wind direction.
Only one plume thickness read.
Plume read at ~ 4 ft directly above emitting surface.
Individual opacity readings taken each 15 sec, recorded
to nearest 5% opacity.
Readings terminated if vehicle obstructs line of sight.
Readings terminated if vehicles passing in opposite
direction creates intermixed plume.
Data Reduction
Two-min time-averages consisting of eight consecutive
15-sec readings.
Certification
Per Tennessee requirements
5-14
-------
Implied in the Ml specification that the plume be read ~ 4 ft above
the emitting surface, is the fact that observations will be made against a
terrestrial (vegetation) background. TjiejrejjJJ;_s_oJlj3jie_sj^
ventjona1^mg_ke_generator modifiedto_emi_t^_ho.rj.2.o.at.a]__pJ,uines_..Jno! j carted ttiat_
under theseconditlons_^b_servers are likely to underestimate j)pacHy levels
by even greater margins than those typically associated with M9.12 More
specifically, the study found that as opacity levels increased, opacity
readings showed an increasing negative bias. For example, at 15% opacity,
the observers underestimated opacity by about 5%, and at 40% opacity, ob-
servations averaged about 11% low.12 Black plumes were underestimated at
all opacity levels. ^"^'
Ml specifies that only one plume thickness be read which is consistent
with all the federal methods. It includes qualifying provisions that:
(1) readings terminate if vehicles passing in opposite directions create an
intermixed plume; but (2) readings continue if intermixing occurs as a re-
sult of vehicles moving in the same direction. Unlike (1), the latter con-
dition is considered representative of the surface. The first specification
is comparable to the specification/found in M9 for multiple stacks (e.g.,
PO
stub stacks on baghouses). The intent here is probably to minimize the in-
fluence of increasing plume density which results from "overlaying" multiple
plumes.
Finally, Ml specifies nominal 15-sec observations comparable to those
for M9. This is in contrast to M22 which uses the stopwatch method to re-
cord the duration of visible emissions.
5.2.2.2 Data Reduction/Evaluation Procedures--
There are two basic approaches that can be used to reduce opacity
readings for comparison with VE regulations. One approach involves the
time-averaging of consecutive 15-sec observations over a specified time
period to produce an average opacity value. M9 uses this approach by cal-
culating a 6-min value (the average based on 24 consecutive observations).
As noted earlier, the 6-min averaging period is inappropriate for open dust
5-15
-------
sources as these typically produce brief, intermittent opacity peaks rather
than a sustained opacity level. As a result, a continuous 6-min period of
observation could include a substantial fraction of time with no activity
and thus no source of VE. In the development of Ml, the State of Tennessee
concluded that a shorter averaging period--2 min (i.e., eight consecutive
15-sec readings) was appropriate for roads and parking lots.
Although not specified in Ml, VE from open sources could be evaluated
using time-aggregating techniques. For example, the discrete 15-sec read-
ings could be employed in the time-aggregating framework. In this case,
the individual observations are compiled into a histogram from which the
number of observations (or equivalent percent of observation time) in
excess of the desired opacity may then be ascertained. The principal
advantage of using the time-aggregate technique as a method to reduce VE
readings is that the resultant indicator of opacity conditions is then
compatible with regulations that include a time exemption clause. Under
time exemption standards, a source is permitted opacity in excess of the
standard for a specified fraction of the time (e.g., 3 min/hr). The con-
cept of time exemption was originally developed to accommodate stationary
source combustion processes.
Without more detailed supporting information, it is difficult to deter-
mine which of the two approaches is most appropriate for evaluating VE from
open sources. With respect to time-averaging, statistics of observer bias
in reading plumes from a smoke generator do indicate at least a slight de-
crease in the "accuracy" of the mean observed opacity value as averaging
time decreases. In Ml (2-min average), this is reflected in the inclusion
of an 8.8% buffer for observational error. This buffer is taken into ac-
count before issuing a Notice of Violation.10 For M9, the 6-min average
opacity value is typically associated with a maximum observer bias of +7.5%.
One potential problem with applying time-averaging to opacity from
roads and parking lots, is that the resulting average will be sensitive to
variations in source activity. For example, interpreting one conclusion
5-16
-------
offered in support of Method 1, it is likely that under moderate wind con-
ditions a single vehicle pass will produce only two opacity readings i 5%.10
Averaging these with six zero (0) readings yields a 2-min value below any
reasonable opacity standard. Yet, under the same conditions with two or
more vehicle passes, the average value will suggest elevated opacity levels.
While there is no information available on the use of time aggregation for
open source opacity, it appears that this approach would more easily accom-
modate variations in level of source activity. For this reason alone, it
may be the evaluation approach better suited to roads and parking lots.
5.3 OTHER METHODS FOR DETERMINING COMPLIANCE
5.3.1 Parameter Monitoring for Ducted Source Controls
Federal, State, and local air regulatory agencies are concerned that
the methods currently available are not always adequate to determine that
sources operate and maintain their control equipment in a compliance mode.
Because stack testing provides only a relatively short-term measure of com-
pliance, it is difficult to determine if a source remains in compliance
after initial compliance is achieved. The only method currently accepted
for measuring continuous compliance is the use of a continuous emission
monitor (CEM), although many constraints limit the use of CEM's including
the high cost and reliability.
Compliance also may be determined by parameter monitoring. Standard
industrial practice includes parameter monitoring to improve quality con-
trol, safety in the workplace, and product yield and to provide a means of
accounting for raw materials and product use. In the field of environmental
control, certain control device parameters have traditionally been measured,
and these parameters have been used with varying levels of sophistication
to provide an indication of how well the device is performing.
5-17
-------
Parameter monitoring provides a useful tool to operators and control
agency personnel for the following purposes:
1. To determine a maintenance schedule;
2. To check on operation and maintenance practices;
3. To prevent, detect, and diagnose malfunctions;
4. To assure that appropriate corrective action has been taken in the
case of malfunctions;
5. To assure that the control device is operating properly during
performance testing; and
6. To assess control equipment performance and compliance on a con-
tinuing basis.
Parameter monitoring procedures for ESPs, fabric filters, and wet scrubbers
are discussed below.
5.3.1.1. Electrostatic Precipitators—
ESP performance is a function of the electrical power required to
charge and attract the particles toward the collection plates. ESP per-
formance parameters are the primary and secondary voltage and current
levels for each of the fields or transformer-rectifier (T-R) sets. The
voltage and current going to the T-R set is known as the primary voltage
and current, respectively. The secondary voltage and current is the elec-
tricity going from the T-R set to the high voltage electrodes (wires) in-
side the ESP. The secondary voltage and current levels are more useful and
specific for indicating performance and diagnosing typical malfunctions than
are the primary voltage and current levels. If both secondary meters are
not available, secondary power levels can be estimated by the following
equation:
5-18
-------
SP = PV x PC x EFF (5-1)
where: SP = secondary power (watts)
PV = primary voltage (volts)
PC = primary current (amperes)
EFF = T-R set efficiency (percent) = typically 60 to 70%
Secondary power can be more accurately and directly calculated if both
secondary meters are available and calibrated by the following equation:
SP = SV x SC (5-2)
where: SV = secondary voltage (kV)
SC = secondary current (mA)
After the power level is calculated for each ESP field, one can graph
or tabulate the field power levels to determine their interrelationship.
The lowest power level is experienced by the inlet field, and the power
level steadily increases for the subsequent fields in the direction of gas
flow. A malfunction is indicated if the field power levels do not show a
steady increase from the inlet field to the outlet field.
Table 5-5 presents recommended parameters for monitoring ESP perfor-
mance. Secondary ESP performance parameters are gas temperature, moisture
content, spark rate, and ash hopper operation. Comparison of the inlet and
outlet gas temperature is useful to indicate potential problems with gas
in-leakage. ESP performance is sensitive to resistivity, and recordkeeping
of inlet gas temperature and moisture content can be used to indicate prob-
lems with high resistivity along with spark rate records. Proper operation
of the ash hopper and ash handling system is important for short-term and
long-term ESP performance, since severe problems in ash removal can cause
permanent damage to the high voltage wires and collection plates. Ash
hopper heaters and hopper level indicators should be monitored to alert
operators of any problems experieced.
5-19
-------
TABLE 5-5. RECOMMENDED OPERATING PARAMETERS FOR MONITORING OF
ESP PERFORMANCE
Secondary voltage for each T-R set (kilovolts)
Secondary current for each T-R set (nrilliampereres)
Primary voltage for each T-R set (volts)
Primary current for each T-R set (amperes)
Inlet gas temperature (°F)
Outlet gas temperature (°F)
Gas moisture content (% H20)
Hopper level indicator
Hopper heater indicator
5.3.1.2 Fabric Filters—
Ba4^me*ep^©fi4*o^i=ngM=s=not=
=wet=s&r-ubber-s==o;p=ESP-is^ Opacity monitoring and internal inspection of the
tube sheet are the most critical indicators of fabric filter performance.
Inlet gas temperature, bag pressure drop, gas flow rate, bag cleaning
parameters, and ash removal indicators are recordable parameters that can
indicate performance levels or malfunctions. Inlet gas temperature monitor-
ing will indicate that the appropriate temperature range is maintained above
the gas dew point and below the maximum temperature suitable for the bag
material. Bag pressure drop monitoring for each compartment can indicate
sudden or severe problems with bag blinding, bag cleaning, or bag mounting.
Bag cleaning parameter monitoring can indicate malfunctions with the bag
cleaning hardware or timers. Ash removal monitoring can indicate malfunc-
tions with the components of the ash handling system. Table 5-6 presents
recommended parameters for monitoring of fabric filter performance.
5-20
-------
TABLE 5-6. RECOMMENDED OPERATING PARAMETERS FOR MONITORING OF
FABRIC FILTER PERFORMANCE
Inlet gas tempe/atuej) (°F)
Bag pressure drop for each compartment (inches water column)
Bag cleaning conditions:
Pulse: Air pressure (pounds per square inch gauge)
Shake: Shaker motor current (amperes)
Reverse: Reverse-air fan current (amperes)
Bag cleaning cycle:
Pulse: Duration and frequency
Shake: Duration, frequency and delay periods
Reverse: Duration, frequency and delay periods
Fabric filter fan current (amperes)
Fabric filter fan gas temperature (°F)
Since..bag. pressure drop is also a function of gas flow rate, monitoring
gas flow rate can help diagnose performance problems. Gas flow rate can be
indicated by measuring fan current and gas temperature.
Recordkeeping of bag replacement information in conjunction with param-
eter and opacity monitoring is recommended to assess the adequacy of bag-
house operation and maintenance. Bag replacement information includes date
and specific location(s) of the bag(s) replaced and a description of bag
failure (e.g., bleeding, cuff-seal tear, pinholes, or large holes).
Repetition of the same bag failures in the same locations warrant further
investigation and inspection.
5-21
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5.3.1.3 Wet Scrubbers-
Parameter monitoring for wet scrubbers is particularly important because
conventional opacity observations of steam plumes are complicated by exhaust
gas moisture content, weather conditions, and the variable distances for
steam detachment. To monitor the potential degradation in control device
performance, parameter monitoring is being recommended to or required of
wet scrubber owner/operators in lieu of opacity. The operating parameters
selected for monitoring are gas pressure drop across each scrubber and the
liquid flow rate to each scrubber. Pressure drop and liquid flow are per-
formance parameters because they indicate the extent of: (1) atomization
of water droplets; and (2) the acceleration of particles through the venturi
section to become collected by the slower moving droplets. Monitoring of
these parameters can indicate malfunctions in the scrubber pumping system
(i.e., pumps and piping) and the need to adjust the variable throat opening
(if applicable). The example calculation in subsection 4.4.1 includes cost
information for this monitoring capability.
Other significant parameters worthy of consideration for monitoring
are included in Table 5-7. Total solids concentration monitoring can in-
dicate when spray nozzles become plugged and ineffective. Scrubber water
pH monitoring will indicate when the acidity or alkalinity levels need to
be adjusted to prevent corrosion damage. When applicable, monitoring the
pressure drop across the separator (or mist eliminator) can indicate pluggage
or other problems resulting in reentrainment of particle-bearing droplets.
Since scrubber and separator pressure drop levels are also dependent upon
gas flow rate, monitoring gas flow rate can also help diagnose performance
problems. Gas flow rate can be indicated by measuring fan current (amperes)
and gas temperature.
5-22
-------
TABLE 5-7. RECOMMENDED OPERATING PARAMETERS FOR MONITORING
OF WET SCRUBBER PERFORMANCE
Pressure drop across venturi (inches water column)
Pressure drop across separator (if separate), inches water column
Scrubber water feed rate (gallons per minute)
Scrubber water solids concentration (percent)
Scrubber water pH level (pH)
Scrubber fan current (amperes)
Scrubber fan gas temperature( °F)
5.3.2 Recordkeeping for Open Source Controls
As discussed above, parameter monitoring and associated recordkeeping
are important components in ensuring that a control program meets the speci-
fied permit objectives. Detailed recordkeeping is particularly important
for open source controls as it provides a basis for determining when re-
application of a periodically applied control measure is again needed in
order to maintain acceptable levels of control. The following discussion
focuses on the types of information that should be recorded for open source,
periodically applied control measures.
In many industrial settings, chemical dust suppressants are used to
control emissions from unpaved surfaces. Control efficiency data for PM10
derived from actual source testing have been discussed previously in Sec-
tion 3.0. For chemical dust suppressants applied to unpaved surfaces, the
key control parameters that should be recorded include:
5-23
-------
1. Application procedure.
2. Date of application (and subsequent reapplications).
3. Dilution ratio (parts of chemical/parts of water).
4. Application intensity (L/m2 or gal/yard2).
5. Quantity of chemicals purchased and used.
Application procedure includes method (i.e., spray truck of known capacity
or fixed sprinkler system), number of nozzles in operation, nozzle capacity,
and method for storage of chemical (i.e., storage tank or 55-gal. drums).
In situations where a storage tank is used for the chemical, a flowmeter
should be installed so that the dilution ratio can be verified.
Table 5-8 presents a typical form that can be used to record key param-
eters for a control program using chemical dust suppressants. This form
assumes that facility information concerning number of roadway segments,
storage piles, etc., is already compiled in an emissions inventory format,
and that control parameters can be recorded with reference to this format.
It should be noted that application intensity is the most difficult of
the various parameters to determine directly. However, given appropriate
records for the other application parameters it is possible to estimate
this parameter. Table 5-9 presents an ancillary form suitable for docu-
menting quantity of chemicals purchased and used.
Table 5-10 presents a similar form applicable to a watering control
program. Special care must be taken to document the frequency of applica-
tion. Again, complete records should be compiled with respect to individual
roadway segments or storage areas. In some cases, relatively crude indirect
estimates of frequency may be inferred from total mileage records for the
spray truck. With appropriate equipment, elapsed operating time can easily
be documented for stationary spray systems. As supplementary information,
representative precipitation observations from a standard rain /gause/(0.01
in. increments) should be collected. Similarily, ambient temperature read-
ings from a representative location, should also be recorded.
5-24
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TABLE 5-8. TYPICAL FORM FOR RECORDING CHEMICAL DUST SUPPRESSANT CONTROL PARAMETERS
(Sources: Unpaved roads, road shoulders, exposed areas, storage piles)
Type of Dilution Application Equipment Operator
Date Time chemical ratio inteijS-fty (gal/yd2) Area(s) treated used initials Comments
ro
-------
TABLE 5-9. TYPICAL FORM FOR RECORDING DELIVERY OF CHEMICAL DUST SUPPRESSANTS
Chemical Quantity Delivery
Date Time delivered delivered agent Facility destination Comments
ro
cr>
Denote whether suppressant will be applied immediately upon receipt or placed in storage.
-------
TABLE 5-10. TYPICAL FORM FOR RECORDING WATERING PROGRAM CONTROL PARAMETERS
(Sources: Unpaved roads, road shoulders, exposed areas,
storage piles)
Climatic parameters
Application Arab.temp.Date/amt.of Equipment Operator
Date Time intensity (gal/yd2) Area(s) treated (°F) last rainfall used initials Comments
CJ1
ro
-------
Table 5-11 presents a recordkeeping form for paved road control tech-
niques (the types of information recorded are similar to that for unpaved
road controls). Records should focus on frequency of surface cleaning and
in the case of flushing, application intensity. Although not included,
equipment maintenance forms may also be of value as they may indicate pe-
riods of time in which the equipment was unavailable, and thus not perform-
ing the expected control function.
Research conducted to date indicates that the control efficiency for
roadway controls will depend upon traffic volume as well as predominant
vehicle characteristics (i.e., weight and speed). For this reason it is
recommended that periodic traffic counts and tabulations of vehicle type be
undertaken for the various road segments being controlled. Counts may be
accomplished by automatic counters, or as an alternative, short term (30 min
to 1 hr) manual counts may also be taken (see Appendix C). In similar
fashion, vehicle speed and average vehicle weight may also be ascertained.
5.3.3 Paved Surface Silt Loading
For paved surfaces, silt loading measurements may provide an appropri-
ate indicator for monitoring the effectiveness of control programs. As in-
dicated in Section 2, variations in silt loading have been shown to account
for a considerable fraction of the variance in experimentally determined
paved road emission factors.
One potentially feasible approach to paved road performance monitoring
is based on comparison of a calculated emission factor (or equivalently
emissions assuming constant ADT) using "the baseline" or uncontrolled state,
to a calculated emission factor for the controlled (i.e., monitored) state.
In both cases, these estimates are based on silt loading measurements col-
${<$(ub
lected by appropriate personnel. In order for this approach to work, sound
sampling/analysis protocols must be developed. The following discusses
some of the requirements of a sound5protocol for silt loading measurements.
Possible problems that might be encountered in interpreting the calcula-
tions are also discussed.
5-28
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TABLE 5-11. TYPICAL FORM FOR RECORDING PAVED ROAD/PARKING AREA CONTROL PARAMETERS
(Sources: Paved roads, parking areas, miscellaneous storage surfaces)
Amt. water
Treatment type applied Equipment Operator
Date Time (F, BS, VS, FBS) Area(s) treated (if used) used initials Comments
en
ro
to
F refers to flushing; BS refers to broom sweeping; VS refers to vacuum sweeping; FBS refers to flushing followed by broom sweeping.
-------
The first requirement in applying this approach involves specification
of a realistic baseline (or uncontrolled) silt loading value(s) for the
surface of interest. At a minimum, the baseline value should reflect the
influence of temporal variations such as occasional cleaning by rainfall,
and increased loadings due to winter sanding. This specification should
also consider spatial variations. For example, a single industrial facility
is likely to exhibit a relatively wide range of baseline values, depending
upon conditions such as: (1) vehicle mix and speed; (2) presence or absence
of curbs; and (3) proximity to unpaved surfaces or industrial processes
which serve as sources for surface loading (e.g., carryout).
An equally important consideration in using silt loading measurements
as a monitoring tool, is the need to collect and analyze samples in a man-
ner consistent with that outlined in Appendices A and B. The uncertainty
associated with using loading values developed under different sampling and
analysis (S/A) procedures is not known. However, the potential to systemati-
cally bias the calculations certainly exists if the S/A procedures used
greatly differ from those documented in Appendices A and B.
A related requirement involves the need to estimate the uncertainties
associated with the present S/A sampling technique. The reproducibility of
the collection method is not well known particularly for the silt loading
range typical of industrial facilities.
5-30
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REFERENCES FOR SECTION 5.0
1. U.S. Environmental Protection Agency. PM10 SIP Development Guide.
Preliminary Draft, Office of Air Quality Planning and Standards,
Research Triangle Park, NC, August 1984.
2. Farthing, W. E., et al. "A Protocol for Size-Specific Emission Measure-
ments," Paper 85-14.3, 78th Annual Meeting of the Air Pollution Control
Association, Detroit, MI, June 1985.
3. Williamson, A. D., et al. "Development of a Source PM10 Sampling Train
Using Emission Gas Recycle (EGR)," Paper 85-14.2, 78th Annual Meeting
of the Air Pollution Control Association, Detroit, MI, June 1985.
4. Wilson, R. R., and W. B. Smith. Procedures Manual for Inhalable Par-
ticulate Sampler Operation. Final Report. EPA Contract No. 68-02-
3118, Southern Research Institute, Birmingham, AL, November 1979.
5. Smith, W. B., et al. Sampling and Data Handling Methods for Inhalable
Particulate. EPA-600/7-82-036, U.S. Environmental Protection Agency,
Research Triangle Park, NC, May 1982.
6. Standards of Performance for New Stationary Sources - Primary Aluminum
Industry (Appendix A, Method 14). Federal Register, Volume 41, No. 17,
January 26, 1976.
7. Del. Green Associates. Alternative Methods for Visual Determination of
the Opacity of Emissions from Stationary Sources. Final Report, EPA
Contract No. 68-01-5110, Task Order No. 54.
8. Standards of Performance for New Stationary Sources - Basic Oxygen
Process Furnaces. Federal Register, Volume 48, No. 14, January 20,
1983.
5-31
-------
9. Standards of Performance for New Stationary Sources - Asphalt Roofing.
Federal Register. Volume 47, No. 152, August 6, 1982.
10. Walton, J. W. , and E. C. Koontz. "Fugitive Dust Reading Technique
from Roads and Parking Lots." Paper 83-39.3, 76th Annual Meeting of
the Air Pollution Control Association, Atlanta, GA, June 1983.
11. Telephone conversation, Mr. John W. Walton, Tennessee Division of Air
Pollution Control, Nashville, TN, September 1984.
12. Rose, T. H. Evaluation of Trained Visible Emission Observers for
Fugitive Opacity Measurement. EPA-600/3-84-093, U.S. Environmental
Protection Agency, Research Triangle Park, NC, October 1984.
5-32
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APPENDIX A
PROCEDURES FOR SAMPLING SURFACE/BULK MATERIALS
A-l
-------
APPENDIX A
PROCEDURES FOR SAMPLING OF SURFACE/BULK MATERIALS
The starting point for development of the recommended procedures for
collection of road dust and aggregate material samples was a review of
American Society of Testing and Materials (ASTM) Standards. When practical,
the recommended procedures were structured identically to the ASTM standard.
When this was not possible, an attempt was made to develop the procedure in
a manner consistent with the intent of the majority of pertinent ASTM Stan-
dards.
A.I UNPAVED ROADS
The main objective in sampling the surface material from an unpaved
road is to collect a minimum gross sample of 23 kg (50 Ib) for every 4.8 km
(3 miles) of unpaved road. The incremental samples from unpaved roads
should be distributed over the road segment, as shown in Figure A-l. At
least four incremental samples should be collected and composited to form
the gross sample.
The loose surface material is removed from the hard road base with a
whisk broom and dustpan. The material should be swept carefully so that
the fine dust is not injected into the atmosphere. The hard road base below
the loose surface material should not be abraided so as to generate more
fine material than exists on the road in its natural state.
Figure A-2 presents a data form to be used for the sampling of unpaved
roads.
A-2
-------
3=-
CO
K
L = 4.8km(3 Mi.)
o
CO
-Sample Strip 20cm (8 in.) Wide
L= 1.6km (1 Mi.)
Figure A-l. Location of incremental sampling sites on an unpaved road.
-------
Sample
No
SAMPLING DATA
Unpaved Roads
Date
Recorded by.
Type of Material Sampled:.
Site of Sampling:
SAMPLING METHOD
1 . Sampling device: whisk broom and dust pan
2. Sampling depth: loose surface material
3. Sample container: metal or plastic bucket with sealed poly liner
4. Gross sample specifications:
(a) 1 sample of 23kg (50 Ib.) minimum for every 4.8km (3 mi.) sampled
(b) composite of 4 increments: lateral strips of 20cm (Sin.) width extending over traveled
portion of roadway half
Indicate deviations from above method:
SAMPLING DATA
Sample
No.
Time
Location
Surface
Area
Depth
Quantity
of Sample
DIAGRAM
Figure A-2. Sampling data form for unpaved roads.
A-4
-------
A. 2 PAVED ROADS
Ideally, for a given paved road, one gross sample per every 8 km (5
miles) of paved roads should be collected. For industrial roads, one gross
sample should be obtained for each road segment in the plant. The gross
sample should consist of at least two separate increments per travel lane.
Thus, the gross sample collected from a four-lane roadway would consist of
eight sample increments.
Figure A-3 presents a diagram showing the location of incremental sam-
ples for a four-lane road. Each incremental sample should consist of a
lateral strip 0.3 to 3 m (1 to 10 ft) in width across a travel lane. The
exact width is dependent on the amount of loose surface material on the
paved roadway. For visually dirty road, a width of 0.3 m (1 ft) is suffi-
cient; but for a visually clean road, a width of 3 m (10 ft) is needed to
obtain an adequate sample.
The above sampling procedure may be considered as the preferred method
of collecting surface dust from paved roadways. In many instances, however,
the collection of eight sample increments may not be feasible due to man-
power, equipment, and traffic/hazard limitations. As an alternative method,
samples can be obtained from a single strip across all the travel lanes.
When it is necessary to resort to this sampling strategy, care must be
taken to select sites that have dust loading and traffic characteristics
typical of the entire roadway segment of interest. In this situation,
sampling from a strip 3 m to 9 m (10 to 30 ft) in width is suggested. From
this width, sufficient sample can be collected, and a step toward repre-
sentativeness in sample acquisition will be accomplished.
Samples are removed from the road surface by vacuuming, preceded by
broom sweeping if large aggregate is present. The samples should be taken
from the traveled portion of the lane with the area measured and recorded
on the appropriate data form. With a whisk broom and a dust pan, the larger
A-5
-------
-8km (5 Mi.) of similar road type
Increment
Figure A-3. Location of incremental sampling sites on a paved road.
-------
particles are collected from the sampling area and placed in a clean,
labeled container (plastic jar or bag). The remaining smaller particles
are then swept from the road with a electric broom-type vacuum sweeper. The
sweeper must be equipped with a preweighed, prelabeled, disposable vacuum
bag. Care must be taken when installing the bags in the sweeper to avoid
torn bags which can result in loss of sample. After the sample has been
collected, the bag should be removed from the sweeper, checked for leaks
and stored in a prelabeled, gummed envelope for transport. Figure A-4
presents a data form to be used for the sampling of paved roads.
Values for the dust loading on only the traveled portion of the road-
way are needed for inclusion in the appropriate emission factor equation.
Information pertaining to dust loading on curb/berm and parking areas is
necessary in estimating carry-on potential to determine the appropriate
Industrial Road Augmentation factor.
A. 3 STORAGE PILES
In sampling the surface of a pile to determine representative proper-
ties for use in the wind erosion equation, a gross sample made up of top,
middle, and bottom incremental samples should ideally be obtained since the
wind disturbs the entire surface of the pile. However, it is impractical
to climb to the top or even middle of most industrial storage piles because
of the large size.
The most practical approach in sampling from large piles is to minimize
the bias by sampling as near to the middle of the pile as practical and by
selecting sampling locations in a random fashion. Incremental samples
should be obtained along the entire perimeter of the pile. The spacing
between the samples should be such that the entire pile perimeter is
traversed with approximately equidistant incremental samples. If small
piles are sampled, incremental samples should be collected from the top,
middle, and bottom.
A-7
-------
SAMPLING DATA
Paved Road Loading
Date
Recorded By
Type of Material Sampled:
Site of Sampling:
Type of Pavement: Asphalt/Concrete
No. of Traffic Lanes
Surface Condition
3.
4.
SAMPLING METHOD
1. Sampling device: Portable vacuum cleaner (broom sweep first if loading is heavy)
2. Sampling depth: Loose surface material
Sample container: Metal or plastic bucket with sealed poly liner
Gross sample specifications:
(a) 1 sample within 100 m of the air sampling site
(b) composite of up to 3 increments: lateral strips of 1 m minimum width extending
from curb to curb
(c ) total sample weight of at least 4.5 Kg
Indicate deviations from above method:
SAMPLING DATA
Sample
No.
Vac
Bag
Time
Surface
Area
Quantity
of Sample
Sample
No.
Vac
Bag
Time
Surface
Area
Quantity
of Sample
DIAGRAM
-+H-
K-
7/80
Figure A-4. Sampling data for paved roads.
A-8
-------
An incremental sample (e.g., one shovelful) is collected by skimming
the surface of the pile in a direction upward along the face. Every effort
must be made by the person obtaining the sample not to purposely avoid sam-
pling larger pieces of raw material. Figure A-5 presents a data form to be
used for the sampling of storage piles.
In obtaining a gross sample for the purpose of characterizing a load-in
or load-out process, incremental samples sould be taken from the portion of
the storage pile surface: (1) which has been formed by the addition of ag-
gregate material or (2) from which aggregate material is being reclaimed.
A-9
-------
Sample
No
SAMPLING DATA
Storage Piles
Date
Recorded by.
Type of Material Sampled:.
Site of Sampling:
SAMPLING METHOD
1. Sampling device: pointed shovel
2. Sampling depth: 10- 15cm (4-6 inches)
3. Sample container: metal or plastic bucket with sealed poly liner
4. Gross sample specifications:
(a) 1 sample of 23kg (50 Ib.) minimum for every pile sampled
(b) composite of 10 increments
5. Minimum portion of stored material (at one site) to be sampled: 25%
Indicate deviations from above method:
SAMPLING DATA
Sample
No.
Time
Location (Refer to map^
Surface
Area
Depth
Quantity
of Sample
Figure A-5. Sampling data form for storage piles.
A-10
-------
APPENDIX B
PROCEDURES FOR LABORATORY ANALYSIS OF
SURFACE/BULK SAMPLES
B-l
-------
APPENDIX B
PROCEDURES FOR LABORATORY ANALYSIS OF
SURFACE/BULK SAMPLES
B.I SAMPLES FROM SOURCES OTHER THAN PAVED ROADS
B.I.I Sample Preparation
Once the 23 kg (50 Ib) gross sample is brought to the laboratory, it
must be prepared for silt analysis. This entails dividing the sample to a
workable size.
A 23 kg (50 Ib) gross sample can be divided by using: (1) mechanical
devices; (2) alternate shovel method; (3) riffle; or (4) coning and quarter-
ing method. Mechanical division devices are not discussed in this section
since they are not found in many laboratories. The alternate shovel method
is actually only necessary for samples weighing hundreds of pounds. There-
fore, this appendix discusses only the use of the riffle and the coning and
quartering method.
ASTM Standards describe the selection of the correct riffle size and
the correct use of the riffle. Riffle slot widths should be at least three
times the size of the largest aggregate in the material being divided. The
following quote describes the use of the riffle:1
1 D2013-72. Standard Method of Preparing Coal Samples for Analysis.
Annual Book of ASTM Standards, 1977.
B-2
-------
"Divide the gross sample by using a riffle. Riffles properly used will
reduce sample variability but cannot eliminate it. Riffles are shown
in Figure B-l, (a) and (b). Pass the material through the riffle from
a feed scoop, feed bucket, or riffle pan having a lip or opening the
full length of the riffle. When using any of the above containers to
feed the riffle, spread the material evenly in the container, raise
the container, and hold it with its front edge resting on top of the
feed chute, then slowly tilt it so that the material flows in a uniform
stream through the hopper straight down over the center of the riffle
into all the slots, thence into the riffle pans, one-half of the sam-
ple being collected in a pan. Under no circumstances shovel the sample
into the riffle, or dribble into the riffle from a small-mouthed con-
tainer. Do not allow the material to build up in or above the riffle
slots. If it does not flow freely through the slots, shake or vibrate
the riffle to facilitate even flow."
The procedure for coning and quartering is best illustrated in Figure
B-2. The following is a description of the procedure: (1) mix the mate-
rial and shovel it into a neat cone; (2) flatten the cone by pressing the
top without further mixing; (3) divide- the flat circular pile into equal
quarters by cutting or scraping out two diameters at right angles; (4) dis-
card two opposite quarters; (5) thoroughly mix the two remaining quarters,
shovel them into a cone, and repeat the quartering and discarding procedures
until the sample has been reduced to 0.9 to 1.8 kg (2 to 4 Ib). Samples
likely to be affected by moisture or drying must be handled rapidly, pre-
ferably in an area with a controlled atmosphere, and sealed in a container
to prevent further changes during transportation and storage. Care must be
taken that the material is not contaminated by anything on the floor or
that a portion is not lost through cracks or holes. Preferably, the coning
and quartering operation should be conducted on a floor covered with clean
paper. Coning and quartering is a simple procedure which is applicable to
all powdered materials and to sample sizes ranging from a few grams to several
hundred pounds.2
Silverman, L., et al., Particle Size Analysis in Industrial Hygiene,
Academic Press, New York, 1971.
B-3
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Feed Chute
Riffle Sampler
(a)
Riffle Bucket and
Separate Feed Chute Stand
(b)
Figure B-l. Sample dividers (riffles).
B-4
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Figure B-2. Coning and quartering.
B-5
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The size of the laboratory sample is important—too little sample will
not be representative and too much sample will be unwieldy. Ideally, one
would like to analyze the entire gross sample in batches, but this is not
practical. While all ASTM Standards ackhowledge this impracticality, they
disagree on the exact size, as indicated by the range of recommended samples,
extending from 0.05 to 27 kg (0.1 to 60 Ib).
The main principle in sizing the laboratory sample is to have suffi-
cient coarse and fine portions to be representative of the material and to
allow sufficient mass on each sieve so that the weighing is accurate. A
recommended rule of thumb is to have twice as much coarse sample as fine
sample. A laboratory sample of 800 to 1,600 g is recommended since that is
the largest quantity that can be handled by the scales normally available
(1,600-g capacity). Also, more sample than this can produce screen clogging
for the 8 in. diameter screens normally available.
B.I.2 Laboratory Analysis of Samples for Silt Content
The basic recommended procedure for silt analysis is mechanical, dry
sieving. A step-by-step procedure is given in Table B-l. The sample should
be oven dried for 24 hr at 230°F before sieving. The sieving time is vari-
able; sieving should be continued until the net sample weight collected in
the pan increases by less than 3.0% of the previous net sample weight col-
lected in the pan. A minor variation of 3.0% is allowed since some sample
grinding due to inter-particle abrasion will occur, and consequently, the
weight will continue to increase. When the change reduces to 3.0%, it is
thought that the natural silt has been passed through the No. 200 sieve
screen and that any additional increase is due to grinding.
Both the sample preparation operations and the sieving results can
be recorded on Figure B-3.
B-6
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TABLE B-l. SILT ANALYSIS PROCEDURES
1. Select the appropriate 8-in. diameter, 2-in. deep sieve sizes. Recom-
mended U.S. Standard Series sizes are: 3/8 in., No. 4, No. 20, No. 40,
No. 100, No. 140, No. 200, and a pan. Comparable Tyler Series sizes can
also be utilized. The No. 20 and the No. 200 are mandatory. The others
can be varied if the recommended sieves are not available or if buildup
on one particular sieve during sieving indicates that an intermediate
sieve should be inserted.
2. Obtain a mechanical sieving device such as a vibratory shaker or a
Roto-Tap.
3. Clean the sieves with compressed air and/or a soft brush. Material
lodged in the sieve openings or adhering to the sides of the sieve should
be removed (if possible) without handling the screen roughly.
4. Obtain a scale (capacity of at least 1,600 g) and record make, capacity,
smallest division, date of last calibration, and accuracy (if available).
5. Tare sieves and pan. Check the zero before every weighing. Record
weights.
6. After nesting the sieves in decreasing order with pan at the bottom, dump
dried laboratory sample (probably immediately after moisture analysis)
into the top sieve. Brush fine material adhering to the sides of the con-
tainer into the top sieve and cover the top sieve with a special lid nor-
mally purchased with the pan.
7. Place nested sieves into the mechanical device and sieve for 20 min. Re-
move pan containing minus No. 200 and weigh. Replace pan beneath the
sieves and sieve for another 10 min. Remove pan and weigh. When the dif-
ference between two successive pan sample weighings (where the tare of
the pan has been subtracted) is less than 3.0%, the sieving is complete.
8. Weigh each sieve and its contents and record the weight. Check the zero
before every weighing.
9. Collect the laboratory sample and place the sample in a separate con-
tainer if further analysis is expected.
B-7
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SILT ANALYSIS
Date
Recorded By
Sample No:
Material:
Split Sample Balance:
Make
Capac i ty
Smallest Division
Material Weight (after drying)
Pan + Material:
Pan:
Dry Sample:
Final Weight:
% Silt = Net Weight <200 Mesh
/0 Sllt Total Net Weight X 10°
SIEVING
Time: Start:
Initial (Tare):
10 min:
20 min:
30 rnin:
40 min:
Weight (Pan Only)
SIZE DISTRIBUTION
Screen
3/8 in.
4 mesh
10 mesh
20 mesh
40 mesh
100 mesh
140 mesh
200 mesh
Pan
Tare Weight
(Screen)
Final Weight
(Screen + Sample)
Net Weight (Sample)
%
Comments:
11/81
Figure B-3. Form for recording sample preparation operations and sieving
results.
B-8
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B.2 SAMPLES FROM PAVED ROADS
B.2.1 Sample Preparation and Analysis for Total Loading
The gross sample of paved road dust will arrive at the laboratory in
two types of containers: (1) the broom swept dust will be in plastic bags;
and (2) the vacuum swept dust will be in vacuum bags.
Both the broom swept dust and the vacuum swept dust are weighed on a
beam balance. The broom swept dust is weighed in a tared container. The
vacuum swept dust is weighed in the vacuum bag which was tared and equili-
brated in the laboratory before going to the field. The vacuum bag and its
contents should be equilibrated again in the laboratory before weighing.
The total surface dust loading on the traveled lanes of the paved road
is then calculated in units of kilograms of dust on the traveled lanes per
kilometer of road. When only one strip of length is taken across the
traveled lanes, the total dust loading on the traveled lanes is calculated
as follows:
L = mb + mv (B-l)
£
L ° 7® 4&f <§W^ /©
-------
mbl+ mvl+ mb5+ mv5 +
L = - + (B-2)
mb2 + mv2 + mb6 + mv6
mb3 + mv3 + mb5 + mv7
mb4 + V + mb8 + mv8
L -
where m, = mass of broom sweepings for increment i (kg)
m = mass of vacuum sweepings for increment i (kg)
£• = length of increment i as measured along the road
center line (km)
B.2.2 Sample Preparation and Analyses for Road Dust Silt Content
After weighing the sample to calculate total surface dust loading on
the traveled lanes, the broom swept and vacuum swept dust is composited.
The composited sample is usually small and requires no sample splitting in
preparation for sieving. If splitting is necessary to prepare a laboratory
sample of 800 to 1,600 g, the techniques discussed in Section B.I.I can be
used. The laboratory sample is then sieved using the techniques described
in Section B.I. 2.
B-10
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APPENDIX C
PROCEDURES FOR QUANTIFICATION OF
TRAFFIC CHARACTERISTICS
C-l
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APPENDIX C
PROCEDURES FOR QUANTIFICATION OF
TRAFFIC CHARACTERISTICS
From Section 2.1 of the body of this report, it is apparent that traf-
fic characteristics must be quantified along with road surface dust in order
to utilize the emission factor equations. The following sections provide
data collection techniques and forms for the quantification of traffic
characteristics such as number of vehicles by type (vehicle mix), vehicle
speed, weight, number of wheels, number of travel lanes and percent of
traffic riding on the road berms.
C.I VEHICLE SPEED
There are two ways to measure vehicle speed in the field: (1) radar
guns; and (2) stop-watch timing between two markers. The sampling period
should be 15 to 30 min for each site where a gross sample of road surface
material was collected.
C.2 VEHICLE MIX
The vehicle mix is performed by a observer in the field. The mix
categorizes vehicles passing the observation point by type, weight, and
number of wheels. The total vehicle count divided by the observation
period gives the traffic density for that period. It is important that the
observer identify whether haul or dump trucks are loaded or unloaded.
Figure C-l provides the form used to tabulate vehicle mix data. Vehicle
mix should be determined at the sites where gross samples of road surface
material were collected. The sampling period should be 15 to 30 min for
each site chosen.
C-2
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Sample
No
VEHICLE MIX
Date
Recorded by.
Road Location:.
Road Type:
Sampling Start Time:.
Stop Time:
Vehicle Type/Wt. Axles/Wheels 123456789 10 Total
Cars, Vans &
Pickups
2/4
Dump trucks
(loaded)
Dump trucks
(unloaded)
3/10
3/10
Haul trucks
(loaded)
trucks
(unloaded)
2/6
2/6
Tractor-trailers 5/18
Tractor-trailers 4/14
Figure C-l. Vehicle mix data form.
C-3
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For industrial roads, it is important to meet with plant personnel to
identify the manufacturer and model of heavy-duty vehicles such as haul
trucks so that reliable weights can be determined. For example, Euclid
R-35, R-50, and R-85 weigh 29, 43, and 56 tons unloaded, respectively.
If emission rates are to be determined, the vehicle mixes do provide a
total vehicle count over the 15 to 30 min sampling period, but it is better
to place an automatic traffic counter at the site for a 24-hr period. The
automatic traffic counters allow a much more representative sampling time
(24-hr) while requiring a minimum amount of personnel hours in the field.
C.3 NUMBER OF LANES TRAVELED BY VEHICLES
The observer at each site should identify the number of travel lanes.
This will equal the total number of lanes minus the parking lanes. At in-
dustrial sites, the number of parking lanes will often be zero and the
travel lanes will equal the total number of lanes.
C.4 QUANTIFICATION OF TRAVEL ON ROAD BERM
For vehicle traffic on paved roads, the existence of vehicle traffic
on unpaved berms is important to quantify. This situation can occur when,
for example, two large haul trucks traveling in opposite directions pass on
a two lane paved road. One or both the trucks are often forced to travel
with one set of wheels on the berm. If the berm is unpaved, this could re-
sult in increased emissions. Even if the berm is paved, an increase in
emissions may occur because of loose dust accumulations. The field observer
should record the nature of the berm, i.e., paved (clean or dirty) or un-
paved, and the percentage of vehicles traveling on the berm. Figure C-l
could be used for this purpose. For example, simply circling the symbol
used to indicate a vehicle pass could indicate that the vehicle traveled on
the berm of the road. Based on the percentage of traffic on paved roads
traveling on an unpaved berm, the industrial road augmentation factor (I)
can be determined from Figure C-2.
C-4
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20 40 60 80 100
Percent of Vehicles Traveling on Unpaved Berm (%)
Figure C-2. Determination of industrial road augmentation factor.
C-5
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