EPA-600/2-76-089C
May 1976
Environmental Protection Technology Series
QUASI-STACK SAMPL
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into five series These five broad
categories were established to facilitate further development and application of
environmental technology Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The five series are'
1 Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
This report has been assigned to the ENVIRONMENTAL PROTECTION
TECHNOLOGY series. This series describes research performed to develop and
demonstrate instrumentation, equipment, and methodology to repair or prevent
environmental degradation from point and non-point sources of pollution This
work provides the new or improved technology required for the control and
treatment of pollution sources to meet environmental quality standards.
EPA REVIEW NOTICE
This report has been reviewed by the U.S. Environmental
Protection Agency, and approved for publication. Approval
does not signify that the contents necessarily reflect the
views and policy of the Agency, nor does mention of trade
names or commercial products constitute endorsement or
recommendation for use.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161
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EPA-600/2-76-089c
May 1976
TECHNICAL MANUAL
FOR THE MEASUREMENT OF FUGITIVE EMISSIONS:
QUASI-STACK SAMPLING METHOD
FOR INDUSTRIAL FUGITIVE EMISSIONS
by
H.J. Kolnsberg, P.W. Kalika, R.E. Kenson, andW.A. Marrone
TRC—The Research Corporation of New England
125 Silas Deane Highway
Wethersfield, Connecticut 06109
Contract No. 68-02-1815
ROAP No. 21AUZ-004
Program Element No. 1AB015
EPA Project Officer: Robert M. Statnick
Industrial Environmental Research Laboratory
Office of Energy, Minerals, and Industry
Research Triangle Park, NC 27711
Prepared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, DC 20460
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TABLE OF CONTENTS
SECTION
PAGE
Of
1.0 OBJECTIVE 1
2.0 INTRODUCTION 2
2.1 Categories of Fugitive Emissions 3
2.1.1 Quasi-stack Sampling Method 3
2.1.2 Roof Monitor Sampling Method 4
2.1.3 Upwind-Downwind Sampling Method 4
2.2 Sampling Method Selection 5
2.2.1 Selection Criteria 5
2.2.1.1 Site Criteria 5
2.2.1.2 Process Criteria 6
2.2.1.3 Pollutant Criteria 6
2.2.2 Application of Criteria 6
2.2.2.1 Quasi-Stack Method 7
2.2.2.2 Roof Monitor Method 8
2.2.2.3 Upwind-Downwind Method 8
2.3 Sampling Strategies 9
2.3.1 Survey Measurement Systems 10
2.3.2 Detailed Measurement Systems 10
3.0 TEST STRATEGIES 12
3.1 Pretest Survey 12
3.1.1 Information to be Obtained 12
3.1.2 Report Organization 13
3.2 Test Plan 13
3.2.1 Purpose of a Test Plan 13
3.2.2 Test Plan Organization 15
3.3 Quasi-Stack Sampling Strategies 17
3.4 Survey Quasi-Stack Sampling Strategy .... 17
3.4.1 Sampling Equipment 18
3.4.2 Sampling System Design 19
3.4.3 Sampling Techniques 22
3.4.4 Data Reduction 25
3.5 Detailed Quasi-Stack Sampling Strategy ... 26
3.5.1 Sampling Equipment 26
3.5.2 Sampling System Design 27
3.5.3 Sampling Techniques 28
3.5.4 Data Reduction 28
3.6 Quality Assurance 29
4.0 ESTIMATED COSTS AND TIME REQUIREMENTS 32
4.1 Manpower 32
4.2 Other Direct Costs 32
4.3 Elapsed-Time Requirements 36
4.4 Cost Effectiveness 36
APPENDIX
APPLICATION OF THE QUASI-STACK MEASUREMENT METHOD
TO A GREY-IRON FOUNDRY
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LIST OF FIGURES
FIGURE
3-1
4-1
4-2
PAGE
Typical survey program sampling system 23
Elapsed-time estimates for quasi-stack 37
fugitive emissions sampling programs
Cost effectiveness of quasi-stack fugitive ... 38
emissions sampling programs
TABLE
3-1
3-2
4-1
4-2
4-3
LIST OF TABLES
Pre-test survey information to be obtained .
Control velocities for dusts and fumes . . .
Conditions assumed for cost estimation of. . .
quasi-stack sampling program
Estimated manpower requirements for quasi- . .
stack fugitive emissions sampling programs
Estimated costs other than manpower for quasi-
stack fugitive emissions sampling programs
PAGE
14
21
33
34
35
ii
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1.0 OBJECTIVE
The objective of this Technical Manual is to present the funda-
mental considerations required for the utilization of the Quasi-Stack
Sampling Method in the measurement of fugitive emissions. Criteria for
the selection of the most applicable measurement method and discussions
of general information gathering and planning activities are presented.
Quasi-stack sampling strategies and equipment are described and sampling
system design, sampling techniques, and data reduction are discussed.
Manpower requirements and time estimates for typical applications
of the method are presented for programs designed for overall and speci-
fic emissions measurements.
The application of the outlined procedures to the measurement of
fugitive emissions from a grey-iron foundry is presented as an appendix.
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2.0 INTRODUCTION
Pollutants emitted into the ambient air from an industrial plant
or other site generally fall into one of two types. The first type is
released into the air through stacks or similar devices designed to
direct and control the flow of the emissions. These emissions may be
readily measured by universally-recognized standard sampling techniques.
The second type is released into the air without control of flow or
direction. These fugitive emissions usually cannot be measured using
existing standard techniques.
The development of reliable, generally applicable measurement pro-
cedures is a necessary prerequisite to the development of strategies for
the control of fugitive emissions. This document describes some pro-
cedures for the measurement of fugitive air emissions using the quasi-
stack measurement method described in Section 2.1.1 below.
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2.1 Categories of Fugitive Emissions
Fugitive emissions emanate from such a wide variety of circumstances
that it is not particularly meaningful to attempt to categorize them either
in terms of the processes or mechanisms that generate them or the geometry
of the emission points. A more useful approach is to categorize fugitive
emissions in terms of the methods for their measurement. Three basic
methods exist — quasi-stack sampling, roof monitor sampling, and upwind-
downwind sampling. Each is described in general terms below.
2.1.1 Quasi-stack Sampling Method
In this method, the fugitive emissions are captured in a temporarily
installed hood or enclosure and vented to an exhaust duct or stack of
regular cross-sectional area. Emissions are then measured in the ex-
haust duct using standard stack sampling or similar well recognized
methods. This approach is necessarily restricted to those sources
of emissions that are isolable and physically arranged so as to
permit the installation of a temporary hood or enclosure that will not
interfere with plant operations or alter the character of the process or
the emissions.
Typical industrial sources of fugitive emissions measurable by
the quasi-stack method include:
1. Material transfer operations
Solids - conveyor belts, loading
Liquids - spray, vapors
2. Process leaks
Solids - pressurized ducts
Liquids - pumps, valves
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3. Evaporation
Cleaning fluids - degreasers, wash tanks
Paint solvent vapors - spray booths, conveyors
4. Fabricating operations
Solids - grinding, polishing
Gases - welding, plating
2.1.2 Roof Monitor Sampling Method
This method is used to measure the fugitive emissions entering
the ambient air from building or other enclosure openings such as roof
monitors, doors, and windows from enclosed sources too numerous or un-
wieldy to permit the installation of temporary hooding. Sampling is,
in general, limited to a mixture of all uncontrolled emission sources
within the enclosure and requires the ability to make low air velocity
measurements and mass balances of small quantities of materials across
the surfaces of the openings.
2.1.3 Upwind—Downwind Sampling Method
This method is utilized to measure the fugitive emissions
from sources typically covering large areas that cannot be tem-
porarily hooded and are not enclosed in a structure allowing the
use of the roof monitor method. Such sources include material
handling and storage operations, waste dumps and industrial processes
in which the emissions are spread over large areas or are periodic
in nature.
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The upwind-downwind method quantifies the emissions from such sources
as the difference between the pollutant concentrations measured in the
ambient air approaching (upwind) and leaving (downwind) the source site.
It may also be utilized in combination with mathematical models and
tracer tests to define the contributions to total measured emissions of
specific sources among a group of sources.
2.2 Sampling Method Selection
The initial step in the measurement of fugitive emissions at an
industrial site is the selection of the most appropriate sampling method
to be employed. Although it is impossible to enumerate all the combina-
tions of influencing factors that might be encountered in a specific
situation, careful consideration of the following general criteria should
result in the selection of the most effective of the three sampling
methods described above.
2.2.1 Selection Criteria
The selection criteria listed below are grouped into three general
classifications common to all fugitive emissions measurement methods.
The criteria are intended to provide only representative examples and
should not be considered a complete listing of influencing factors.
2.2.1.1 Site Criteria
Source Isolability. Can the emissions be measured separately from
emissions from other sources? Can the source be enclosed?
Source Location. Is the source indoors or out? Does location
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permit access of measuring equipment?
Meteorological Conditions. What are the conditions representative
of typical and critical situations? Will precipitation interfere
with measurements? Will rain or snow on ground effect dust levels?
2.2.1.2 Process Criteria
Number and Size of Sources. Are emissions from a single, well
defined location or many scattered locations? Is source small
enough to hood?
Homogeneity of Emissions. Are emissions the same type everywhere
at the site? Are reactive effects between different emissions
involved?
Continuity of Process. Will emissions be produced long enough to
obtain meaningful samples?
Effects of Measurements. Are special procedures required to pre-
vent the making of measurements from altering the process or emis-
sions or interfering with production? Are such procedures feasible?
2.2.1.3 Pollutant Criteria
Nature of Emissions. Are measurements of particles, gases, liquids
required? Are emissions hazardous?
Emission Generation Rate. Are enough emissions produced to provide
measurable samples in reasonable sampling time?
Emission Dilution. Will transport air reduce emission concentra-
tion below measurable levels?
2.2.2 Application of Criteria
The application of the selection criteria listed in Section 2.2.1
to each of the fugitive emissions measurement methods defined in Section
2.1 is described in general terms in this section.
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2.2.2.1 Quasi-Stack Method
Effective use of the quasi-stack method requires that the source
of emissions be isolable and that an enclosure can be installed capable
of capturing emissions without interference with plant operations. The
location of the source alone is not normally a factor. Meteorological
conditions usually need be considered only if they directly affect the
sampling.
The quasi-stack method is usually restricted to a single source
and must be limited to two or three small sources that can be effectively
enclosed to duct their total emissions to a single sampling point.
Cyclic processes should provide measurable pollutant quantities during
a single cycle to avoid sample dilution. The possible effects of the
measurement on the process or emissions is of special significance in
this method. In many cases, enclosing a portion of a process in order
to capture its emissions can alter that portion of the process by chang-
ing its temperature profile or affecting flow rates. Emissions may be
similarly altered by reaction with components of the ambient air drawn
into the sampling ducts. While these effects are not necessarily limit-
ing in the selection of the method, they must be considered in designing
the test program and could influence the method selection by increasing
complexity and costs.
The quasi-stack method is useful for virtually all types of emis-
sions. It will provide measurable samples in generally short sampling
times since it captures essentially all of the emissions. Dilution of
the pollutants of concern is of little consequence since it can usually
be controlled in the design of the sampling system.
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2.2.2.2 Roof Monitor Method
Practical utilization of the roof monitor method demands that the
source of emissions be enclosed in a structure with a limited number of
openings to the atmosphere. Measurements may usually be made only of
the total of all emissions sources within the structure. Meteorological
conditions normally need not be considered in selecting this method
unless they have a direct effect on the flow of emissions through the
enclosure opening.
The number of sources and the mixture of emissions is relatively
unimportant since the measurements usually include only the total emis-
sions. The processes involved may be discontinuous as long as a repre-
sentative combination of the typical or critical groupings may be in-
cluded in a sampling. Measurements will normally have no effect on the
processes or emissions.
The roof monitor method, usually dependent on or at least influ-
enced by gravity in the transmission of emissions, may not be useful
for the measurement of larger particulates which may settle within the
enclosure being sampled. Emission generation rates must be high enough
to provide pollutant concentrations of measurable magnitude after dilu-
tion in the enclosed volume of the structure.
2.2.2.3 Upwind-Downwind Method
The upwind-downwind method, generally utilized where neither of
the other methods may be successfully employed, is not influenced by
the number or location of the emission sources except as they influence
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the locating of sampling devices. In most cases, only the total con-
tribution to the ambient atmosphere of all sources within a sampling
area may be measured. The method is strongly influenced by meteorolog-
ical conditions, requiring a wind consistent in direction and velocity
throughout the sampling period as well as conditions of temperature,
humidity and ground moisture representative of normal ambient condi-
tions.
The emissions measured by the upwind-downwind method may be the
total contribution from a single source or from a mixture of many sources
in a large area. Continuity of the emissions is generally of secondary
importance since the magnitude of the ambient air volume into which the
emissions are dispersed is large enough to provide a degree of smooth-
ing to cyclic emissions. The measurements have no effect on the emis-
sions or processes involved.
Most airborne pollutants can be measured by the upwind-downwind
method. Generation rates must be high enough to provide measurable
concentrations at the sampling locations after dilution with the ambient
air. Settling rates of the larger particulates require that the sampling
system be carefully designed to ensure that representative particulate
samples are collected.
2.3 Sampling Strategies
Fugitive emissions measurements may, in general, be separated into
two classes or levels depending upon the degree of accuracy desired.
Survey measurement systems are designed to screen emissions and provide
gross measurements of a number of process influents and effluents at a
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relatively low level of effort in time and cost. Detailed systems are
designed to isolate, identify, and quantify individual contaminant con-
stituents with increased accuracy and higher investments in time and
cost.
2.3.1 Survey Measurement Systems
Survey measurement systems employ recognized standard or state-
of-the-art measurement techniques to screen the total emissions from a
site or source and determine whether any of the emission constituents
should be considered for more detailed investigation. They generally
utilize the simplest available arrangement of instrumentation and pro-
cedures in a relatively brief sampling program, usually without pro-
visions for sample replication, to provide order-of-magnitude type data,
embodying a factor of two to five in accuracy range with respect to
actual emissions.
2.3.2 Detailed Measurement Systems
Detailed measurement systems are used in instances where survey
measurements or equivalent data indicate that a specific emission con-
stituent may be present in a concentration worthy of concern. Detailed
systems provides more precise identification and quantification of spe-
cific constituents by utilizing the latest state-of-the-art measurement
instrumentation and procedures in carefully designed sampling programs.
These systems are also utilized to provide emission data over a range
of process operating conditions or ambient meteorological influences.
Basic accuracy of detailed measurements is in the order of +10 to + 50
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percent of actual emissions. Detailed measurement system costs are
generally in the order of three to five times the cost of a survey sys-
tem at a given site.
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3.0 TEST STRATEGIES
This section describes the approaches that may be taken to success-
fully complete a testing program utilizing the quasi-stack sampling
method described in Section 2.1. It details the information required
to plan the program, describes the organization of the test plan, spe-
cifies the types of sampling equipment to be used, establishes criteria
for the sampling system design, and outlines basic data reduction methods.
3.1 Pretest Survey
After the measurement method to be utilized in documenting the
fugitive emissions at a particular site has been established using the
criteria of Section 2.2, a pretest survey of the site should be corn-
ducted by the program planners. The pretest survey should result in an
informal, internal report containing all the information necessary for
the preparation of a test plan and the design of the sampling system by
the testing organization.
This section provides guidelines for conducting a pretest survey
and preparing a pretest survey report.
3.1.1 Information to be Obtained
In order to design a system effectively and plan for the on-site
sampling of fugitive emissions, a good general knowledge is required of
the plant layout, process chemistry and flow, surrounding environment,
and prevailing meteorological conditions. Particular characteristics
of the site relative to the needs of the owner, the products involved,
the space and manpower skills available, emission control equipment
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installed, and the safety and health procedures observed, will also
influence the sampling system design and plan. Work flow patterns and
schedules that may result in periodic changes in the nature or quantity
of emissions or that indicate periods for the most effective and least
disruptive sampling must also be considered. Most of this information
can only be obtained by a survey at the site. Table 3-1 outlines some
of the specific information to be obtained. Additional information will
be suggested by considerations of the particular on-site situation.
3.1.2 Report Organization
The informal, internal pretest survey report must contain all the
pertinent information gathered during and prior to the site study. A
summary of all communications relative to the test program should be
included in the report along with detailed descriptions of the plant
layout, process, and operations as outlined in Table 3-1. The report
should also incorporate drawings, diagrams, maps, photographs, meteoro-
logical records, and literature references that will be helpful in plan-
ning the test program.
3.2 Test Plan
3.2.1 Purpose of a Test Plan
Measurement programs are very demanding in terms of the scheduling
and completion of many preparatory tasks, observations at sometimes
widely separated locations, instrument checks to verify measurement
validity, etc. It is therefore essential that all of the experiment
design and planning be done prior to the start of the measurement pro-
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TABLE 3-1
PRE-TEST SURVEY INFORMATION TO BE OBTAINED
FOR APPLICATION OF FUGITIVE EMISSION SAMPLING METHODS
Plant
Layout
Drawings:
Building Layout and Plan View of Potential Study Areas
Building Side Elevations to Identify Obstructions and
Structure Available to Support Test Setup
Work Flow Diagrams
Locations of Suitable Sampling Sites
Physical Layout Measurements to Supplement Drawings
Work Space Required at Potential Sampling Sites
Process
Process Flow Diagram with Fugitive Emission Points
Identified
General Description of Process Chemistry
General Description of Process Operations Including
Initial Estimate of Fugitive Emissions
Drawings of Equipment or Segments of Processes Where
Fugitive Emissions are to be Measured
Photographs (if permitted) of Process Area Where
Fugitive Emissions are to be Measured
Names, Extensions, Locations of Process Foremen and
Supervisors Where Tests are to be Conducted
Operations
Location of Available Services (Power Outlets, Main-
tenance and Plant Engineering Personnel, Labora-
tories, etc.)
Local Vendors Who Can Fabricate and Supply Test System
Components
Shift Schedules
Location of Operations Records (combine with process
operation information)
Health and Safety Considerations
Other
Access routes to the areas Where Test Equipment/Instru-
mentation Will Be Located
Names, Extensions, Locations of Plant Security and
Safety Supervisors
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gram in the form of a detailed test plan. The preparation of such a
plan enables the investigator to "pre-think" effectively and cross-check
all of the details of the design and operation of a measurement program
prior to the commitment of manpower and resources. The plan then also
serves as the guide for the actual performance of the work. The test
plan provides a formal specification of the equipment and procedures
required to satisfy the objectives of the measurement program. It is
based on the information collected in the informal pretest survey re-
port and describes the most effective sampling equipment, procedures,
and timetables consistent with the program objectives and site charac-
teristics .
3.2.2 Test Plan Organization
The test plan should contain specific information in each of the
topical areas indicated below:
Background
The introductory paragraph containing the pertinent infor-
mation leading to the need to conduct the measurement program and
a short description of the information required to answer that
need.
Objective
A concise statement of the problem addressed by the test
program and a brief description of the program's planned method
for its solution.
Approach
A description of the measurement scheme and data reduction
methodology employed in the program with a discussion of how each
will answer the needs identified in the background statement.
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Instrumentation/Equipment/Facilities
A description of the instrumentation arrays to be used to
collect the samples and meteorological data identified in the
approach description. The number and frequency of samples to be
taken and the sampling array resolution should be described.
A detailed description of the equipment to be employed and
its purpose.
A description of the facilities required to operate the
measurement program, including work space, electrical power,
support from plant personnel, special construction, etc.
Schedule
A detailed chronology of a typical set of measurements or a
test, and the overall schedule of events from the planning stage
through the completion of the test program report.
Limitations
A definition of the conditions under which the measurement
project is to be conducted. If, for example, successful tests can
be conducted only during occurrences of certain wind directions,
those favorable limits should be stated.
Analysis Method
A description of the methods which will be used to analyze
the samples collected and the resultant data, e.g., statistical or
case analysis, and critical aspects of that method.
Report Requirements
A draft outline of the report on the analysis of the data to
be collected along with definitions indicating the purpose of the
report and the audience for which it is intended.
Quality Assurance
The test plan should address the development of a quality
assurance program as outlined in Section 3.7. This QA program
should be an integral part of the measurement program and be in-
corporated as a portion of the test plan either directly or by
reference.
Responsibilities
A list of persons who are responsible for each phase of the
measurement program, as defined in the schedule, both for the
testing organization and for the plant site.
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3.3 Quasi-Stack Sampling Strategies
The quasi-stack sampling method, as described in Section 2.1.1,
is used to quantify the emissions from a source by capturing the
emissions, entrained in the ambient air, in a temporary hood or enclosure
built over or around the source and directing the captured stream through
a duct of regular cross section for measurement, sampling and analysis
using standard stack techniques. The concentration of the pollutants
in a sampled volume of the captured stream is determined in terms of
micrograms per cubic meter or parts per million and used to determine
the source strength of the pollutants by extrapolation to the total
volume of the captured stream.
Sections 3.4 and 3.5 describe the strategies, sampling equipment,
criteria for sampling system design, sampling techniques and data re-
duction procedures for respectively, survey and detailed quasi-stack
sampling programs.
3.4 Survey Quasi-Stack Sampling Strategy
A survey measurement system, as defined in Section 2.3, is designed
to provide gross measurements of emissions to determine quickly and in-
expensively whether any pollutant constituents should be considered for
more detailed investigation. A quasi-stack measurement system consists
basically of a hood or other enclosure to capture the emissions at the
source, an exhaust duct or stack in which the emissions are measured,
a fan or blower to direct the emissions through the measurement duct, and
the emissions sampling equipment. A survey system capture hood utilizes
the simplest design possible, consistent with the requirement to capture
all of the emissions from the source. Its measurement duct is the
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minimum diameter and length required to convey the suspected pollutants
to their measurement points in sufficient quantity for efficient opera-
tion of the sampling equipment; and the sampling equipment is the
simplest combination that will provide overall measurements of the
suspected pollutants.
3.4.1 Sampling Equipment
Particulate pollutants may be grossly measured most conveniently
using any of a large variety of filter impaction devices. A typical
arrangement consists of an in-duct probe with a collection orifice angled
into the flowing stream, a micro-porous filter in a flow-through holder,
a positive-displacement suction pump and a flow measurement device such
as a rotameter, all connected by small-diameter tubing.
Gaseous pollutants may be grab-sampled for laboratory analysis into
suitably-sized vessels added to the particulate sampling train or
separate sampling ports elsewhere in the measurement duct. On-line
measurements may be made for specific gaseous compounds with bubbler trains
designed for the pollutant of concern.
The total of pollutant-carrying air in the measurement duct is
determined using a pitot tube - draft gage velocity measurement device
in the known, regular cross-section duct area. Air pressure and tempera-
ture are determined using simple menometers and thermometers suitably
located in the duct.
An alternative method for the measurement of particulates and
volatile matter utilizes the recently developed source assessment sampling
system (SASS) train. This train consists of a stainless steel probe that
delivers the sample to an oven module containing three cyclone separators
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in series to provide measurable quantities of particulate matter in three
size ranges: >10 micro meters, 3 to 10 micro,'meters, and 1 to 3 micro
meters. A standard Method 5 type filter, also in series, provides a
fourth size range of <1 micro meter. Organic vapors are collected on a
parous polymer absorber after the sample is cooled by a gas conditioner
on the outlet of the oven. An oxidative impinger entraps the remaining
volatile trace elements to complete the sampling train. Used in combina-
tion with a gas-^sampling assembly, the train can provide all the
information required as to the native and composition of the pollutants
in the sampled stream.
3.4.2 Sampling System Design
The primary concern in the design of a survey quasi-stack sampling
system is insuring that measurable concentrations of the pollutants of
concern are transported intact from the source to the sampling points.
This is accomplished by carefully designing the pollutant-capturing
enclosure, measurement duct and air-moving blower to provide sufficient
air flow to entrain and transport the pollutants.
The size and shape of the pollutant-capturing hood will be dictated
by the size, shape and location of the pollutant source. In general, it
must be. large enough to capture all of the pollutants, but not so large
that the pollutants are diluted below measurable concentrations by an
excessive volume of ambient air.
Hemeon notes that the specific gravity of dusts, vapors or gases
has no bearing on the design of an exhaust system so long as a basic
control velocity is achieved and proposes some basic control velocities
(1") Hemeon, W.C.L., Plant and Process Ventilation, Industrial Press,
Inc., New York. 1963.
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for various ambient draft conditions for dusts and fumes. These are
summarized in Table 3-2.
The air velocity at the open face of a hood is related to the air
flow rate and the face area by
Q = VA, [Equation 3-1]
where Q = air volume flow rate, cubic feet per minute
V = air velocity, feet per minute
A = hood face area, square feet
The minimum air flow rate required to control the emissions is calculated
as the product of the hood face area and the control velocity indicated
in Table 3-2.
Since the calculated air flow rate is sufficient to provide capture
velocity of the emissions at the largest opening of the hood, the trans-
port of the emissions through the smaller cross-sectional area measurement
duct is assured. In order to effectively measure the velocity, tempera-
ture and pressure of the flowing stream to determine the total flow rate,
and to provide the most efficient sample flows, flow in the measurement
duct should be in the turbulent range with a Reynold's number of 2 x 105
for a typical smooth-walled duct. The Reynolds number for air is roughly
calculated as
Re = dV x 110
where Re = Reynolds number, dimensionless
d = duct diameter, feet
V = air velocity, feet per minute
Since V = Q/A
and A = lid2/4
by substitution, Re = 14OQ
and d - 14J£ = ^^ = ? x ^-^
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TABLE 3-2
CONTROL VELOCITIES FOR DUSTS AND FUMES
Ambient Draft
Characteristics
Nearly draftless
Medium drafts
Very drafty
Control Velocities, feet per minute
Small dust quantities
40 - 50
50 - 60
70 - 80
Large dust quantities
50 - 60
60 - 70
75 - 100
(Dust quantities may be roughly estimated in terms of their effect
on visibility. A quantity of dust sufficient to obscure visibility
of major details should be considered a large quantity.)
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The blower or fan used to provide the required air flow rate should,
in general, be selected to provide about twice the calculated rate to
allow for adjustments for inaccuracies in estimates or assumptions. The
actual flow rate may be controlled by providing a variable bypass air
duct downstream of the measurement duct. A typical survey sampling
system arrangement is illustrated schematically in Figure 3-1. Actual
system layouts will, of course, be governed by space requirements at the
source site- The minimum straight duct runs of 3 duct diameters up-
stream and downstream of the measurement and sampling ports must be
provided to ensure that the sampled flow reaches and remains in the
laminar region.
3.4.3 Sampling Techniques
Sampling must be scheduled and carefully designed to ensure that
data representative of the emission conditions of concern are obtained.
Effective scheduling demands that sufficient knowledge of operations
and process conditions be obtained to determine proper starting times
and durations for samplings. The primary concern of the sampling design
is that sufficient amounts of the various pollutants are collected to
provide meaningful measurements.
Each of the various sample collection and analysis methods has an
associated lower limit of detection, typically expressed in terms of
micrograms of captured solid material and either micrograms per cubic
meter or parts per million in air of gases. Samples taken must provide
at least these minimum amounts of the pollutants to be quantified. The
amount (M) of a pollutant collected is the product of the concentration
-22-
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Exhaust
I
I
K5
U>
•^ ••• ou IIMII. ^
T
d -,
1
Air flow
pitot
-
5
Part
«• oa mm. »•
Measurement
duct
icle
Gas
sampler t
8
_
T
Jypa
lir
Control
valve
ss
Blov
rer
Source
Fig. 3-1. Typical survey program sampling system.
-------
of the pollutant in the air (x) and the volume of air sampled (W), thus,
M (micrograms) = x (micrograms/cubic feet) x V (cubic feet).
To ensure that a sufficient amount of pollutant is collected, an ade-
quately large volume of air must be passed through such samplers as
particle filters or gas absorbing trains for a specific but uncontrolla-
ble concentration. The volume of air (W) is the product of its flow
rate (F) and the sampling time (T), or,
W (cubic feet) = F (cubic feet/minute) x T (minutes).
Since the sampling time is most often dictated by the test conditions,
the only control available to an experimenter is the sampling flow rate.
A preliminary estimate of the required flow rate for any sample may be
made if an estimate or rough measurement of the concentration expected
is available. The substitution and rearrangement of terms in the above
equations yields:
F (cubic feet/minute) = M (micrograms)/x (micrograms/cubic feet)
x T (minutes). [Equation 3-3]
This equation permits the calculation of the minimum acceptable flow
rate for a required sample size. Flow rates should generally be ad-
justed upward by a factor of at least 1.5 to compensate for likely in-
accuracies in estimates of concentration. The upper limit of the sampling
flow rate is determined by the velocity of the measurement stream. To
minimize the possibility of creating disturbances in the measurement
stream that will permit entrained particulates to escape the entraining
air flow and thus measurement by downstream samplers, the sample stream
-24-
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velocity at inlet must not exceed the measurement stream velocity. Thus,
F max = Q d2 [Equation 3-4)
s
where F max = maximum sampler flow rate, cubic feet per minute
Q = air volume flow rate, cubic feet per minute
ds = sampling line inlet diameter, feet
d = measurement duct diameter, feet
Grab samples of gaseous pollutants provide for no means of pollu-
tant sample quantity control except in terms of the volume of the sample.
Care should be taken, therefore, to correlate the sample size with the
requirements of the selected analysis method.
3.4.4 Data Reduction
When the sampling program has been completed and the samples analyzed
to yield pollutant concentrations in micrograms per cubic meter or parts
per million per unit volume in the captured stream, the values are then
multiplied by the flow rate of the captured stream which is assumed to
contain all the pollutants omitted by the source, to yield the source
strength in terms of grams per unit time.
In cases where the background pollutant level in the ambient air
used as the source pollutant transport medium is known or suspected to
be of a magnitude sufficient to mask the source pollutant emission level,
a sampling run of the ambient air may be required for better quantifica-
tion of the source strength. This may be accomplished using the sampling
system either with the source inoperative or with the hood directed so
as to avoid capturing any source emissions. The samples from such a
sampling run are analyzed in the same manner as the source samples to
-25-
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yield the pollutant concentrations in the ambient air. These are then
subtracted from the source sample values before calculating the source
strengths.
3.5 Detailed Quasi-Stack Sampling Strategy
A detailed measurement system is designed to more precisely identify
and quantify pollutants that a survey measurement or equivalent data
indicate as possible problem areas. A detailed system is necessarily
more complex than a survey system in terms of equipment, system design,
sampling techniques and data reduction. It requires a much larger invest-
ment in equipment, time and manpower to yield data detailed and dependable
enough for direct action toward achieving emissions control. The basic
configuration of a detailed quasi-stack sampling system is the same as
that of a survey system — an emissions capturing enclosure, a measure-
ment duct and an air mover plus the sampling and measuring equipment.
Its capturing enclosure may, depending on the characteristics of the
source, be considerably more complex, providing more of the functions of
a permanent system. The measurement duct is usually longer, providing
space for the installation of a greater number of sampling devices or
more complex, on-line specific pollutant measuring arrangements.
3.5.1 Sampling Equipment
The pollutants to be characterized by a detailed quasi-stack
sampling system fall into the same two basic classes — airborne particu-
lates and gases -— as those measured by survey systems. Detailed system
sampling and analysis equipment is generally selected to obtain continuous
or semi-continuous measurements of specific pollutants rather than grab-
sampled overall measurement.
-26-
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Particulate samples are collected using the SASS train described
in Section 3.4.1, filter impaction, piezo-electric, particle charge trans-
fer, light or radiation scattering, electrostatic, and size selective or
adhesive impaction techniques. Gases are sampled and analyzed using
flame ionization detectors, bubbler/impinger trains, non-dispersive
infrared or ultraviolet monitors, flame photometry, and other techniques
specific to individual gaseous pollutants.
The selection of suitable sampling equipment should be influenced
by such considerations as portability, power requirements, detection
limits and ease of control.
3.5.2 Sampling System Design
The basic criteria and methods reviewed in Section 3.4.2 for the
design of a survey system are generally applicable to the design of a
detailed system. In cases where the capturing enclosure actually covers
all or part of the source, however, a minor adjustment is required in
the calculation of the required air flow rate. In such cases, the source
serves to block some of the free air flow area and reduces the air flow
required to achieve capture velocity. The elements of Equation 3-1 must
therefore be redefined in
Q = VA
where Q = air volume flow rate, cubic feet per minute
V = air velocity, feet per minute
A = free flow area, square feet
The free flow area is defined as the maximum area between the hood and
the enclosed source in any plant parallel to the open hood face.
-27-
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The calculation of the minimum measurement duct diameter by
Equation 3-2, d = 4.45 x 10 k Q remains unchanged. Straight duct run
requirements of at least 3d upstream and downstream of measurement parts
are required.
3.5.3 Sampling Techniques
Detailed system sampling, like survey system sampling, must be
scheduled and designed to obtain data representative of the emission
conditions of concern. Since a greater number of samples are likely to
be required in a detailed system, care must be taken to ensure that the
total flow rate to the samplers does not exceed the air flow required
for capture velocity at the source enclosure.
A detailed system may be utilized to make comparative measurements
of emissions at different process conditions. It is possible, especially
in cases where the source enclosure closely follows the contours of the
source, that the flow of air induced by the sampling system over the
surface of the source could alter the process from that occurring under
normal operating conditions. While no general method to verify the ex-
istence of this alteration can be defined, it is suggested that an
appropriate analysis be conducted to investigate the possibility and
corrective actions, such as a modification to the enclsoure design, be
taken as required.
3.5.4 Data Reduction
Data obtained in detailed programs is reduced in the same manner as
that obtained in survey programs, relating pollutant concentrations in
the sample volumes to sources strengths. The results are generally more
-28-
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accurate than those of a survey program, due to the combined effects of
the increase in the emissions capture effectiveness of the source en-
closure, the performance of inherently more accurate samplings and
analyses, and the replication of sampling.
3.6 Quality Assurance
The basic reason for quality assurance on a measurement program is
to insure that the validity of the data collected can be verified. This
requires that a quality assurance program be an integral part of the
measurement program from beginning to end. This section outlines the
quality assurance requirements of a sampling program in terms of several
basic criteria points. The criteria are listed below with a brief ex-
planation of the requirements in each area. Not all of the criteria
will be applicable in all fugitive emission measurement cases.
1. Introduction
Describe the project organization, giving details of the
lines of management and quality assurance responsibility.
2. Quality Assurance Program
Describe the objective and scope of the quality assurance
program.
3. Design Control
Document regulatory design requirements and standards ap-
plicable to the measurement program as procedures and specifi-
cations.
4. Procurement Document Control
Verify that all regulatory and program design specifications
accompany procurement documents (such as purchase orders).
5. Instructions, Procedures, Drawings
Prescribe all activities that affect the quality of the
work performed by written procedures. These procedures must
-29-
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include acceptance criteria for determining that these activ-
ities are accomplished.
6. Document Control
Ensure that the writing, issuance, and revision of proce-
dures which prescribe measurement program activities affecting
quality are documented and that these procedures are distributed
to and used at the location where the measurement program is
carried out.
7. Control of Purchase Material, Equipment, and Services
Establish procedures to ensure that purchased material con-
forms to the procurement specifications and provide verification
of conformance.
8. Identification and Control of Materials, Parts, and Components
Uniquely identify all materials, parts, and components that
significantly contribute to program quality for traceability
and to prevent the use of incorrect or defective materials,
parts, or components.
9. Control of Special Processes
Ensure that special processes are controlled and accomplished
by qualified personnel using qualified procedures.
10. Inspection
Perform periodic inspections where necessary on activities
affecting the quality of work. These inspections must be or-
ganized and conducted to assure detailed acceptability of pro-
gram components.
11. Test Control
Specify all testing required to demonstrate that applicable
systems and components perform satisfactorily. Specify that
the testing be done and documented according to written proce-
dures, by qualified personnel, with adequate test equipment
according to acceptance criteria.
12. Control of Measuring and Test Equipment
Ensure that all testing equipment is controlled to avoid
unauthorized use and that test equipment is calibrated and
adjusted at stated frequencies. An inventory of all test
equipment must be maintained and each piece of test equipment
labeled with the date of calibration and date of next calibra-
tion.
-30-
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13. Handling, Storage, and Shipping
Ensure that equipment and material receiving, handling,
storage, and shipping follow manufacturer's recommendations
to prevent damage and deterioration. Verification and docu-
mentation that established procedures are followed is required.
14. Inspection, Test, and Operating Status
Label all equipment subject to required inspections and
tests so that the status of inspection and test is readily
apparent. Maintain an inventory of such inspections and oper-
ating status.
15. Non-conforming Parts and Materials
Establish a system that will prevent the inadvertent use
of equipment or materials that do not conform to requirements.
16. Corrective Action
Establish a system to ensure that conditions adversely af-
fecting the quality of program operations are identified, cor-
rected, and commented on; and that preventive actions are
taken to preclude recurrence.
17. Quality Assurance Records
Maintain program records necessary to provide proof of
accomplishment of quality affecting activities of the measure-
ment program. Records include operating logs, test and in-
spection results, and personnel qualifications.
18. Audits
Conduct audits to evaluate the effectiveness of the mea-
surement program and quality assurance program to assure that
performance criteria are being met.
-31-
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4.0 ESTIMATED COSTS AND TIME REQUIREMENTS
Table 4-1 presents a listing of the conditions assumed for estimat-
ing the costs and time requirements of quasi-stack fugitive emissions
sampling programs using the methodology described in this document. Four
programs are listed, representing simple and more complex levels of
effort for each of the survey and detailed programs defined in Section 3.3.
The combinations of conditions for each program are generally representa-
tive of ideal and more realistic cases for each level and will seldom
be encountered in actual practice. They do, however, illustrate the
range of effort and costs that may be expected in the application of the
quasi-stack technique except in very special instances.
4.1 Manpower
Table 4-2 presents estimates of manpower requirements for each of the
sampling programs listed in Table 4-1. Man-hours for each of the three
general levels of Senior Engineer/Scientist, Engineer/Scientist, and
Junior Engineer/Scientist are estimated for the general task areas out-
lined in this document and for additional separable tasks. Clerical man-
hours are estimated as a total for each program. Total man-hour require-
ments are approximately 500 man-hours for a simple survey program and 1000
man-hours for a more complex survey program and 1400 man-hours for a simple
detailed program and 2600 man-hours for a more comples detailed program.
4.2 Other Direct Costs
Table 4-3 presents estimates for equipment purchases, rentals, cal-
-32-
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TABLE 4-1
CONDITIONS ASSUMED FOR COST ESTIMATION
OF QUASI-STACK SAMPLING PROGRAM
Parameter
Source accessibility
Source geometry
Emissions
Particulate Samplers
Gas Samplers
Experiments
Estimated basic accuracy
Level 1 Program
Simple
Open
Small ,
simple shape
Constant rate,
continuous flow
Filter
Grab
1
+ 500%
Complex
Congested
Large,
complex shape
Variable rate,
interrupted flow
Filter
Bubblers
1
+ 200%
Level 2 Program
Simple
Open
Small ,
simple shape
Constant rate,
continuous flow
Cascade impactor
BID
4
+ 100%
Complex
Congested
Large,
complex shape
Variable rate,
interrupted flow
Impactor, light
scatter
FID, infrared
12
+ 50%
I
OJ
U)
I
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TABLE 4-2
ESTIMATED MANPOWER REQUIREMENTS FOR QUASI STACK
FUGITIVE EMISSIONS SAMPLING PROGRAMS
Estimates in Man-Hours
Task
Pretest Survey
Test Plan
Equipment Acquisition
Field Set-Up
Field Study
Sample Analysis
Data Analysis
Report Preparation
Totals
Engineer/Scientist Total
Clerical
Grand Total
Level 1 Programs
Simple
Senior
Engr/Sci
4
8
4
16
16
8
8
16
80
Engr/
Sci
12
12
4
32
56
8
8
16
140
480
40
520
Junior
Engr/
Tech
0
0
12
80
120
16
16
8
252
Complex
Senior
Engr/Sci
8
12
4
16
32
8
8
32
120
Engr/
Sci
24
16
8
72
128
12
12
32
304
920
60
980
Junior
Engr/
Tech
0
4
28
120
280
24
24
16
496
Level 2 Programs
Simple
Senior
Engr/Sci
8
12
8
16
32
20
20
40
156
Engr/
Sci
24
24
24
64
128
80
120
80
544
1320
100
1420
Junior
Engr/
Tech
0
12
48
120
240
120
40
40
620
Complex
Senior
Engr/Sci
12
16
12
32
64
40
40
60
276
Engr/
Sci
36
32
36
128
240
180
240
160
1052
2528
120
2648
Junior
Engr/
Tech
16
12
52
240
480
240
80
80
1200
-------
TABLE 4-3
ESTIMATED COSTS OTHER THAN MANPOWER FOR QUASI-STACK
FUGITIVE EMISSIONS SAMPLING PROGRAMS
i
U)
Ul
I
Cost Item
Equipment
Sampler Purchases
Calibration
Repairs /Maintenance
Blower/Fan
Construction
Enclosure
Ducting
Shipping
Trailer Rental
Vehicle Rentals
On-Site Communications
TOTAL
Level 1 Programs
Simple
$1000
0
50
200
500
300
200
0
280
100
$2630
Complex
$1200
50
50
200
800
500
400
0
560
100
$3860
Level 2 Programs
Simple
$8000
300
200
300
1200
300
800
500
900
300
$12800
Complex
$12000
500
300
300
1800
800
1200
500
1200
300
$19100
-------
ibration and repairs; on-site construction of enclosures and ducts;
shipping and on-site communications for each of the listed programs.
Total costs are approximately $2,600 for a simple survey program and
$4,000 for a more complex survey program, and $13,000 for a simple de-
tailed program and $19,000 for a more complex detailed program.
4.3 Elapsed-Time Requirements
Figure 4-1 presents elapsed-time estimates for each of the listed
programs broken down into the task areas indicated in the manpower es-
timates of Table 4-2. Total program durations are approximately 12
weeks for a simple survey program and 16 weeks for a more complex survey
program, and 29 weeks for a simple detailed program and 38 weeks for a
more complex detailed program.
4.4 Cost Effectiveness
Figure 4-2 presents curves of the estimated cost effectiveness of
the quasi-stack technique, drawn through points calculated for the
four listed programs. Costs for each program were calculated at $30
per labor hour, $40 per man day subsistence for field work for the man-
power estimates of Table 4-2, plus the other direct costs estimated in
Table 4-3.
-36-
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I
OJ
Task
Pre-test
survey
Test plan
preparation
Equipment
acquisition
Field
set-up
Field
study
Sample
analysis
Data
analysis
Report
preparation
Weeks
15 10 15 20 25 30 35 40
i i i i I I I i I I I I I i i i i I i i I I I I I i i I I i I I i i i i i I I I
1=1
1=
dZI
Simple survey program
Complex survey program
Simple detailed program
Complex detailed program
KSSSX^SSl
i I I I I I i I I I I I I I I I I I I I I I I I I I I I i I I i i i I I i n i i
15 10 15 20 25 30 35 40
Weeks
Fig. 4-1. Elapsed-time estimates for quasi-stack fugitive emissions sampling programs.
-------
500
400
300
Survey program
_
'
-------
APPENDIX A
APPLICATION OF THE QUASI-STACK
MEASUREMENT METHOD TO A GREY-IRON FOUNDRY
-39-
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A.1.0 INTRODUCTION
This appendix presents an application of the quasi-stack fugitive
emissions measurement system selection and design criteria to a grey-
iron foundry mold pouring operation. The criteria for the selection
of the method and the design procedures for both survey and detailed
sampling systems as presented in Sections 3.4 and 3.5 of this document
are discussed.
-40-
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A.2.0 BACKGROUND INFOBMATIQN
The following information relative to the pouring operation of the
subject grey-iron foundry would ordinarily be compiled from interviews
and observations during a visit to the plant for a pre-test survey:
Mold pouring operations are conducted at many locations over the
foundry floor, with the molten iron carried from the melting furnace
in a pouring ladle by means of an overhead crane. Ladles are selected
to provide at least enough melt to completely fill a mold in a single
pouring. As many as six smaller molds, with flasks up to about 8 cubic
feet in volume, may be filled from a single small ladle; while the
largest ladle can carry enough melt to fill one mold in a flask up to
300 cubic feet. Actual pouring of the melt takes from about 30 seconds
for the smallest molds to nearly 6 minutes for the largest molds. The
emission character is the same for any size pouring, consisting mostly
of grey-iron fume and a variety of gaseous compounds, principally hydro-
carbons and carbon oxides. Emission character immediately after the
pouring, while there is still a gas-producing reaction between the melt
and the binder material in the mold, is different from that during the
pour, with almost no fume and more gaseous compounds being generated.
Emissions during this venting period are highest immediately after
the pour and lessen with time, becoming negligible after about 4 minutes
for small molds and about 10 minutes for the largest molds. Molds are
spaced to provide working room around all four sides, so that pouring
operations, at least for the larger molds, may be readily isolated and
emissions from other operations excluded. Pouring is always accom-
plished from above the mold, with mold sprues generally located near one
-41-
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edge. Mold gas vents are located over the entire top surface of the
mold. Though foundry operations are continuous, the pouring of a
single mold may be scheduled at any time without seriously disturbing
normal operations.
-42-
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A.3.0 METHOD SELECTION
Selecting the most practical method to quantify the pollutants
emitted during the pouring operation involves the evaluation of the site,
process and pollutant information gathered during the pre-test survey
in terms of the criteria of Section 2.2 as follows:
Site Criteria - the typical mold is located within the foundry
building with enough room around the mold to provide complete
isolation from other operations and installation of an
enclosure and measuring equipment.
Process Criteria - emissions are from locations small enough
to totally enclose. No reactive effects will occur with other
emissions. Emission duration is only 10-15 minutes. Measure-
ment equipment installation and application will not alter
emissions, process or production schedules.
Pollutant Criteria - emissions to be measured are particulates
and gases, neither of which is hazardous. Generation rate
should produce measurable concentrations in reasonable transport
air flows.
The criteria in this case satisfy the requirements for the quasi-
stack method. Measurements made of a single pouring can provide in-
formation relative to the emission rate for a given volume or mass of
melt, and, by extrapolation, for the entire foundry. A survey program
may be utilized to roughly determine the overall emissions rate and estab-
lish whether the concentrations of particulates or gases that may reach
the ambient air will result in the creation of an objectionable condition.
If such a condition is indicated, a detailed program will identify and
quantify specific pollutants to assist in the selection and design of
control equipment to reduce emissions to alleviate the condition. The
design of both survey and detailed systems is described in following
sections.
-43-
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A.4.0 SURVEY MEASUREMENT SYSTEM
To measure the contribution of a single pouring's emission to the
ambient air, emissions from the mold and ladle during the pouring and
from the mold alone during the post-pouring venting must be captured
and transported to sampling equipment. Samples must be taken at a
high rate to ensure that measurable pollutant quantities are isolated
during the short process duration. In order to keep the required hood
structure to a manageable size and still obtain a reasonable sampling
time, a medium-sized mold, 3x4x4 feet is selected, representative of
the average-sized casting produced in the foundry. This size casting
requires about 4 minutes to pour and has a venting period of 7 to 8 min-
utes. Consultations with foundry engineers indicating that a clear-
ance of 3 feet above the front pouring edge of the mold will leave
sufficient room for handling the pouring ladle, a hood is designed as
shown in Figure A-l, providing this clearance and a 3 inch overlap over
each edge of the mold.
The face area of this hood is about 16 square feet. The control
velocity for a large quantity of fume in a medium drafty ambient atmos-
phere, as indicated in Table 3-2, is 60-70 feet per minute. Using the
higher velocity value for V and the calculated area for A in Equation 3-1,
Q = VA = 70 x 16 = 1120 cubic feet per minute.
For this flow rate, the minimum measurement duct diameter is calculated
from Equation 3-2,
d = 7 x 10~4Q = .78 feet
d = 9.4 inches
-------
Fig. A-1. Survey program sampling hood design.
-------
A standard 10 inch diameter duct will provide for the proper flow and
require only 8 to 10 feet of length to provide the required flow straight-
ening upstream and downstream of the measurement and sampling probes.
The flow measuring instruments located in the duct consist of a
pitot pressure tube, a static pressure port and a mercury thermometer
inserted to the duct centerline about 40 inches (4d) from the hood
transition section.
The particulate sampling tube is located about 20 inches downstream
of the flow measuring instruments and consists of a 1/2 inch diameter
right-angled probe, this diameter chosen to provide as much sample as
possible during the rather short emission duration. The sampling flow
rate is calculated from Equation 3-4 as
F max = Q d| = 2.8 cubic feet per minute.
d2~
At 2.8 cubic feet per minute, the particulate filter will be exposed to
about 11 cubic feet during the pouring and about 20 cubic feet during
the venting period. Grab-sampling 4 cubic foot bags valved into the
sampling line will be readily filled during the pour and venting to
provide separate measurements of gaseous emission.
-46-
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A.5.0 DETAILED MEASUREMENT SYSTEM
Assuming that the survey system measurements indicate emission rates
resulting in pollutant concentrations in a range possibly hazardous to
the health of the foundry personnel, further identification of the
specific pollutant components and their concentrations by means of a
detailed measurement system will either establish the need for emission
controls or eliminate the cause for concern.
The detailed system will utilize three separate on-line particulate
measurement devices to determine size distribution, mass, composition
and organic characteristics. These are:
1. Particle charge transfer monitor
2. Cascade impactor
3. EPA isokinetic sampling train
The combination will provide positive identification of all particulates
and readily separate fume from background particles.
Alternatively, the SASS train described in Section 3.4.1 may be
utilized to provide data on the particulates and the volatile matter in
the sampled stream.
Gaseous emissions will be identified and quantified by on-line
measurements using a flame ionization detector for hydrocarbons and a
non-dispersive infrared monitor for carbon monoxide.
The 3x4x4 foot mold used in the survey program is again utilized,
with the capture hood modified to provide almost total enclosure of the
mold and pouring ladle by extending the hood to the floor and providing
flexible shrouds across the open front face. The sampling system is
shown with shrouds in place in Figure A-2.
-47-
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In this configuration, the free flow area of the hood is maintained
at about the same size as in the Level 1 system and the air flow rate
calculation remains the same, yielding Q = 1120 cubic feet per minute
and d = 10 inches. The sampling probes may be reduced in size since the
on-line samplers flow requirements are significantly less than those
required for overall measurements. Equation 3-4 shows, for example,
that a 1/16 inch line will provide about 30 times the required 200
milliliter per minute flow rate required by the FID monitor without ex-
ceeding measurement duct velocity restrictions.
All measurement devices fcr this system are shown within a labora-
tory trailer, since most foundry floors will not allow the installation
of sensitive devices without a strong possibility of either external
contamination or interference with normal work patterns.
In use, the floor area within the hood/shroud enclosure is carefully
swept to remove any non-pouring particles. A "dry" run, without the
ladle of melt in position, is conducted before the pour to measure the
background pollutant concentrations. These are subtracted from the
concentrations measured during the pour before source strength calcula-
tions are performed.
-48-
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Particulate Measurement Devices
IKOR EPA CASCADE
IMPACTOR
Capture
hood
HC and CO line
Instruments
Fig. A-2. Detailed program sampling system.
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/2-76-089c
2.
3. RECIPIENT'S ACCESSION-NO.
4. TITLE AND SUBTITLE
Technical Manual for the Measurement of Fugitive
Emissions: Quasi-Stack Sampling Method for
Industrial Fugitive Emissions
5. REPORT DATE
May 1976
6. PERFORMING ORGANIZATION CODE
7 AUTHOR(S)
H .1. Kolnsberg,
W.A Marrone
P.W. Kalika, R. E. Kenson, and
6. PERFORMING ORGANIZATION REPORT NO.
9 PERFORMING ORGANIZATION NAME AND ADDRESS
10. PROGRAM ELEMENT NO.
TRC--The Research Corporation of New England
125 Silas Deane Highway
Wethersfield, Connecticut 06109
1AB015; ROAP 21AUZ-004
11. CONTRACT/GRANT NO.
68-02-1815
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Task Final; 6/75-3/76
14. SPONSORING AGENCY CODE
EPA-ORD
15. SUPPLEMENTARY NOTES Project Officer for this technical manual is Robert M. Statnick,
Mail Drop 62, Ext 2557.
16 ABSTRACTThe technical manual presents fundamental considerations that are required
in using the Quasi-Stack Sampling Method to measure fugitive emissions. Criteria
for selecting the most applicable measurement method and discussions of general
information-gathering and planning activities are presented. Quasi-Stack sampling
strategies and equipment are described, and sampling system design, sampling
techniques, and data reduction are discussed. Manpower requirements and time
estimates for typical applications of the method are presented for programs designed
for overall and specific emissions measurements. The application of the outlined
procedures to the measurement of fugitive emissions from a gray-iron foundry is
presented as an appendix.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
Air Pollution Foundries
Industrial Processes
Measurement
Sampling
Estimating
Gray Iron
b.IDENTIFIERS/OPEN ENDED TERMS
Air Pollution Control
Stationary Sources
Fugitive Emissions
Quasi-Stack Sampling
c. COSATl Field/Group
13B
13 H
14B
11F
3 DISTRIBUTION STATEMENT
Unlimited
19. SECURITY CLASS (This Report)
Unclassified
21. NO OF PAGES
54
20. SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
-50-
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