EPA 340/1 -77-022
NOVEMBER 1977
Stationary Source Enforcement Series
INSPECTION MANUAL FOR ENFORCEMENT OF
NEW SOURCE PERFORMANCE STANDARDS
COAL
PREPARATION
PLANTS
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Enforcement
Office of General Enforcement
Washington, D.C. 20460
-------
INSPECTION MANUAL FOR THE
ENFORCEMENT OF NEW SOURCE
PERFORMANCE STANDARDS:
COAL PREPARATION PLANTS
Contract No. 68-01-3150
EPA Project Officer: Mark Antell
Prepared for:
U.S. ENVIRONMENTAL PROTECTION AGENCY
Division of Stationary Source Enforcement
Washington, D.C.
August 1977
-------
This report was furnished to the U.S. Environmental Protec-
tion Agency by PEDCo Environmental, Inc., Cincinnati, Ohio,
in fulfillment of Contract No% 68-01-3150. The contents of
this report are reproduced herein as received from the
contractor. The opinions, findings and conclusions expressed
are those of the authors and not necessarily those of the'
U.S. Environmental Protection Agency-
11
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ACKNOWLEDGMENT
This report was prepared for the U.S. Environmental
Protection Agency by PEDCo Environmental, Inc., Cincinnati,
Ohio. The Project Director was Mr. Timothy W. Devitt; the
Project Manager, Mr. Yatendra M. Shah. Principal authors
were Messrs. James R. Burke, Norman J. Kulujian, and Yatendra
M. Shah.
Mr. Mark Antell was Project Officer for the U.S.
Environmental Protection Agency. The authors appreciate the
contributions made to this study by Mr. Antell and other
members of the U.S. Environmental Protection Agency.
111
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TABLE OF CONTENTS
Page
1.0 INTRODUCTION 1-1
2.0 SUMMARY OF NSPS REGULATIONS 2-1
2.1 Applicability and Designation of 2-1
Affected Facility
2.2 Definitions 2-1
2.3 Emission Standards for Particulate Matter 2-2
2.4 Monitoring of Operations 2-2
2.5 Test Methods and Procedures 2-3
3.0 COAL PREPARATION INDUSTRY 3-1
3.1 Coal Markets 3-2
3.2 Purpose of Coal Preparation 3-2
3.3 Development of Mining Methods and Changing 3-3
Preparation Standards
3.4 Location of Coal Preparation Plants 3-5
3.5 Economics of Coal Preparation 3-9
4.0 PROCESS DESCRIPTION 4-1
4.1 Capabilities of Coal Preparation 4-2
4.2 Application of Cleaning Processes to 4-4
Size Increments
4.3 Coal Sizing 4-5
4.4 Pneumatic Cleaning 4-9
v
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TABLE OF CONTENTS (continued)
Page
4.5 Jig-Table Washing 4-12
4.6 Heavy-Media Washing Plant 4-15
4.7 Water Clarification Plant 4-19
4.8 Thermal Drying 4-22
4.9 Emission Sources and Control Devices 4-26
4.10 Control Devices, Their Capabilities and 4-27
Efficiencies
5.0 INSTRUMENTATION AND RECORDS 5-1
5.1 Process Instrumentation 5-2
5.2 Records 5-5
6.0 START-UP, SHUTDOWN, AND MALFUNCTIONS 6-1
6.1 Start-up and Shutdown 6-1
6.2 Changes in Coal Feed 6-3
6.3 Malfunction of Support Equipment 6-4
6.4 Malfunction in Sources of Fugitive Dust 6-5
6.5 Malfunction of Control Devices 6-13
7.0 EMISSION PERFORMANCE TESTS 7-1
7.1 Pretest Procedures 7-1
7.2 Test Monitoring 7-5
8.0 PERIODIC COMPLIANCE INSPECTIONS 8-1
8.1 Performing the Periodic Inspection 8-1
8.2 Determining Compliance Status 8-13
REFERENCES 8-15
Vi
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TABLE OF CONTENTS (continued)
Page
APPENDIX A NEW SOURCE PERFORMANCE STANDARDS A-l
COAL PREPARATION PLANTS
APPENDIX B STANDARD TEST METHODS B-l
Vll
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LIST OF FIGURES
No. Page
3-1 Trends in Coal Production and Coal Cleaning 3-6
3-2 Illustrative Cleaning Circuit 3-10
4-1 Coal Sizing Circuit 4-6
4-2 Hammermill 4-7
4-3 Rotary Breaker 4-7
4-4 Pneumatic Cleaning Circuit 4-10
4-5 Air Table 4-11
4-6 Jig Table Cleaning Circuit 4-13
4-7 Air-Pulsated Jig 4-14
4-8 Deister Table 4-14
4-9 Heavy-Media Cleaning Circuit 4-16
4-10 Heavy-Media Cyclone 4-17
4-11 Water Clarification Circuit 4-20
4-12 Froth Flotation Unit 4-21
4-13 Fluid-Bed Dryer 4-23
4-14 Multilouver Dryer 4-24
4-15 Cascade Dryer 4-24
4-16 Flash Dryer 4-25
Vlll
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LIST OF TABLES
No. Page
2-1 Comparison of NSPS and State Emission 2-5
Regulations
3-1 Location of Coal Washing Capacity and 3-8
Bituminous/Lignite Coal Production
3-2 Cost Analysis, Raw and Washed Coals 3-13
3-3 Illustrative Preparation Costs, Eastern 3-15
Kentucky Coals
3-4 Illustrative Preparation Costs, West 3-17
Virginia Coals
4-1 Coal Size Ranges for Cleaning Equipment 4-4
4-2 Cyclong Variables 4-28
4-3 Scrubber Variables 4-29
4-4 Orifice Flow Rates 4-30
4-5 Operating Temperatures 4-31
7-1 Emission Performance Test Responsibilities 7-6
7-2 Checklist for Performance Test 7-7
8-1 Checklist for Periodic Inspection 8-2
IX
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1.0 INTRODUCTION
On October 24, 1974, under Section 111 of the Clean Air
Act, as amended, the Environmental Protection Agency pro-
posed standards of performance for new and modified coal
preparation plants. The proposed standards were modified on
the basis of comments received from various interested
parties. The Federal Register of January 15, 1976, presents
the standards of performance for new and modified coal
preparation plants.
This report presents procedures for inspection of coal
preparation facilities toward determination of their com-
pliance with New Source Performance Standards (NSPS). It
also provides background information that will aid the
inspector in understanding the coal preparation process and
the effects of operating parameters on process emissions.
Section 2.0 deals with the emission regulations for the
coal preparation industry, presenting a brief history of
NSPS, a discussion of the need for modifications of the
proposed standards, and a summary of emission regulations,
including monitoring and recordkeeping requirements.
Regulations of individual states pertaining to coal prepara-
tion plants are compared with the NSPS.
1-1
-------
Background information on the coal preparation industry
is presented in Section 3.0, which describes the purpose of
coal preparation, market requirements, market trends, geo-
graphic location of plants, and the economics of coal
preparation.
Section 4.0 describes the coal preparation process and
the major process variations, outlining the function of
process equipment, the potential emission points, and the
emission control techniques currently in use in the coal
preparation industry.
Instrumentation and record-keeping practices of the
newer plants are discussed in Section 5.0.
Section 6.0 deals with emissions that occur during
start-up, shutdown, and malfunction, with operational
procedures for maintaining such emissions at or below the
required levels.
Section 7.0 presents in detail the inspection procedure
and check points for observation during performance tests.
Test duration, operating conditions, and interpretation of
instrument indications are discussed.
Section 8.0 outlines periodic inspection procedures and
the relationship of periodic inspection data to those ob-
tained in the initial performance test.
1-2
-------
The NSPS as presented in the Federal Register are
reproduced in Appendix A. Appendix B presents standard
test procedures.
1-3
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2.0 SUMMARY OF NSPS REGULATIONS
The following summary of New Source Performance Stan-
dards for coal preparation plants is given in a format
corresponding to that used in the Federal Register, as
reproduced in Appendix A. Regulations proposed by indi-
vidual states are discussed briefly.
2.1 APPLICABILITY AND DESIGNATION OF AFFECTED FACILITY
Coal preparation plants processing less than 200 tons
per day of coal are exempted by the NSPS. The affected
facilities in the coal preparation plants processing more
than 200 tons per day are thermal dryers, pneumatic coal
cleaning equipment (air tables), coal processing and con-
veying equipment (including breakers and crushers), coal
storage systems, and coal transfer and loading facilities.
2.2 DEFINITIONS
Underground mining operations are not considered part
of the coal preparation process. Coal storage and transfer
sources are governed by NSPS only if they form a part of the
coal preparation facility; isolated coal storage and transfer
stations are excluded. Open coal storage piles are excluded
from the definition of coal storage systems.
2-1
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2.3 EMISSION STANDARDS FOR PARTICULATE MATTER
Regulations for emissions of particulate matter from
coal processing facilities are as follows:
2.3.1 Thermal Dryer
Exhaust gases discharged into atmosphere shall not
contain particulate matter in excess of 0.070 gram/dry
standard cubic meter (g/dscm) or 0.031 grain/dry standard
cubic foot (gr/dscf) and shall not exhibit 20 percent or
greater opacity.
2.3.2 Pneumatic Coal Cleaning Equipment (Air Table)
The gases discharged into atmosphere from an air table
shall not contain particulate matter in excess of 0.040
g/dscm (0.018 gr/dscf) and shall not exhibit 10 percent or
greater opacity.
2.3.3 Other Facilities
The gases discharged into atmosphere from other coal
conveying, processing, and storage and transfer facilities
shall not exhibit 20 percent or greater opacity.
2.4 MONITORING OF OPERATIONS
The NSPS regulations require continuous monitoring of
exit gas temperature on the thermal dryer. If a venturi
scrubber is used to control emissions from the thermal
dryer, continuous monitoring of water supply pressure and of
pressure loss through the venturi constriction are required.
2-2
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2.5 TEST METHODS AND PROCEDURES
The regulations prescribe standard test methods and
procedures for particulate emission measurements. Method 5
is to be used for the concentration of particulate matter
and associated moisture content, method 1 for sample and
velocity traverse, method 2 for velocity and volumetric flow
rate, and method 3 for gas analysis. The sampling time for
method 5 is at least 60 minutes, and the minimum sample
volume is 30.0 dscf. Sampling is not to be started until 30
minutes after start-up and is to be terminated before shut-
down procedures commence. Standard test methods are given
in Appendix B.
Most of the states have no separate emission regula-
tions for coal preparation plants, which usually are encom-
passed under process emission regulations. Three eastern
coal-producing states - Pennsylvania, Virginia, and West
Virginia - and the State of New Mexico have formulated regu-
lations for coal preparation plants.
The Pennsylvania regulations state a single allowable
emission rate of 0.02 gr/dscf for thermal dryers and air
tables. The concentration for thermal dryers is more
stringent than the NSPS allowable concentration of 0.031
gr/dscf; the NSPS allowable emission rate for air tables is
0.018 gr/dscf. The Virginia regulations allow 105 pounds
2-3
-------
per hour of particulate emissions from thermal dryers pro-
cessing 200 tons per hour or more coal. Allowable emissions
from the air table are 0.05 gr/dscf. The West Virginia
regulations for thermal dryers installed after March 1,
1970, range from 0.07 to 0.10 gr/dscf. Allowable emissions
from an air table are 0.05 gr/dscf. New Mexico State regu-
lations require good control of coal processing and con-
veying operations; no quantitative limits are specified. A
comparison of NSPS regulations and these State regulations
is presented in Table 2.1.
2-4
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Table 2-1. NSPS AND STATE EMISSION REGULATIONS
Coal processing
facility
Thermal dryer
Air table
Processing and
conveying
NSPS
0.031 gr/dscf
Opacity: less than
20 percent
0.018 gr/dscf
Opacity: less than
10 percent
Opacity: less than
20 percent
Particulate matter emission regulation
Pennsylvania
0.020 gr/dscf
0.020 gr/dscf
No regulation
Virginia
105 Ib/hr
0.05 gr/dscf
No regulation
West Virginia
' Gas flow,
scfm
75,000 or less
111,000 or less
163,000 or less
240,000 or above
gr/dscf
0.10
0.09
O.OB
0.07
0.05 gr/dscf
Fugitive dust control
system required
New Mexico
No regulation
No regulation
Fugitive dust control
system required
to
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3.0 COAL PREPARATION INDUSTRY
In the early part of this century efforts to prepare
coal were directed to sizing the coal to supply lump coal
for domestic use and intermediate sizes for industrial or
bunker use; the fines were usually rejected as unfit for
sale. Development of sizing facilities to meet the demands
of the midcentury coal consumer resulted in highly sophis-
ticated handling and screening facilities. Today's market
requires less sizing than ever before, the primary limita-
tion being maximum size for shipment.
Since the very early days of mining, attempts have been
made to improve the quality of coal by removing slate. These
efforts were made in the underground mines until the advent
of mechanical mining, supported by hand picking in the
"tipple" outside the mine. The first washing was done in
Baum and Norton jigs imported from Europe, followed by the
introduction of the "Chance" washer in 1918. The latter was
an excellent washer utilizing sand and water as a medium,
which has since been displaced by the "heavy media" process
using magnetite. Through the years, many other types of
washers have been introduced and have been abandoned.
3-1
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The means of drying have been improved, although the
original screening equipment has been supplemented only by
centrifuges.
The adoption of Diester tables near the middle of the
century to wash fine coal required supplementary equipment
including centrifuges, froth flotation devices, disc filters,
thickeners, cyclones, and thermal dryers.
3.1 COAL MARKETS
Until the middle of the century the primary coal
markets were domestic, transportation (rail and ship),
metallurgical, and industrial. At present the primary coal
markets are for utility and metallurgical use and for
export. The utility market uses low-quality coals. The
metallurgical market requires the very best coals, com-
pletely prepared. The export market utilizes a quality
somewhat lower than that of the metallurgical coals.
3.2 PURPOSE OF COAL PREPARATION
Coal preparation serves several purposes. One important
purpose is to increase the heating value of the coal by
mechanical removal of impurities. This is often required in
order to find a market for the product. Run-of-mine coal
from a modern mine may incorporate as much as 60 percent
reject materials.
3-2
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Air pollution control often requires partial removal of
pyrites with the ash to reduce the sulfur content of the
coal. Ash content often must be controlled to conform to a
prescribed quality stipulated in contractual agreements.
Because of firing characteristics, it is often as important
to retain the ash content at a given level as it is to
reduce it.
Freight savings are substantial when impurities are
removed prior to loading. Finally, the rejected impurities
are more easily disposed of at the mine site remote from
cities than at the burning site, which is usually in a
populated area.
3.3 DEVELOPMENT OF MINING METHODS AND CHANGING PREPARATION
STANDARDS
The earliest mining system used in England, from which
U.S. practices evolved, was the longwall method. Mining
could proceed from the shaft only a short distance because
no forced ventilation was available. All the coal within
this perimeter was removed prior to extending the shaft
deeper or sinking a new one. No coal preparation of con-
sequence was performed at this time.
The room and pillar method was used in underground
mines in this country because of the nature of and easy
accessibility of the coal beds. Strip mining was introduced
during the second decade of this century, after the develop-
3-3
-------
ment of the steam shovel for the Panama Canal, and the
longwall system was reintroduced on an experimental basis
during the last 20 years. Auger mining was introduced with
the spread of coal stripping, as a supporting method of
recoving coals from underneath a highwall.
Coal is produced currently by the following methods:
Underground mining 45 percent
Mined by hand 0.7
Conventional mining 15.0
Continuous mining 27.7
Longwall mining 1.6
Strip mining 55 percent
Until World War II most coal was loaded by hand and was
obtained from the better seams of coal. Each worker was
responsible for rejecting impurities and (sometimes) fines
in the mine. Outside preparation equipment consisted of
screens, crushers, and picking tables. Washeries were not
common.
Exhaustion of the best coals and adoption of mechanical
mining, which eliminated the removal of impurities in the
mine, required the wider use of cleaning plants incorpora-
ting screens, crushers, picking tables, and washers. These
plants normally practiced hand picking for the lump and egg
sizes (more than 3 inches) and washed the coarser coal (3
in. x 1/4 in.). The fine coal (1/4 x 0) was usually shipped
raw. The reject from such a plant was unlikely to exceed 10
percent of the run-of-mine (ROM) coal.
3-4
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Introduction of the continuous miner requiring "full
seam" mining, elimination of a large portion of the domestic
market, and further exhaustion of the best coals imposed
't—
further requirements on the coal preparation plants. They
were required to clean and dry the 1/4 x 0 coal fraction, the
state of development that is current today. Picking tables
have been eliminated, a fine-coal circuit has been added,
and rejection of 50 percent of the ROM coal is not uncommon.
Fluctuations in coal demand resulted in the dismantling
of plants, some of which were incorporated into other or new
plants, always of larger capacities. The trend has been to
utilize one large plant to process coal from several mines,
even from different seams, at the expense of additional
freight charges and intensified refuse disposal require-
ments. Figure 3-1 indicates the trends in the coal prepara-
tion industry.
Some plants, modified and expanded several times, are
still operating at the original site after 50 years, long
after the original mine has been abandoned.
3.4 LOCATION OF COAL PREPARATION PLANTS
General Considerations
Large coal washing plants are normally located in the
mining areas to accommodate one or more mines. They are
concentrated near the highest-quality coals because of
process economics and market factors.
3-5
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I
CTl
ANNUAL COAL PRODUCTION
COAL MECHANICALLY CLEANED
1947
62 63 64 65 66 67 68 69 70 71 72 73 74 75
YEAR OF PRODUCTION
Figure 3-1. Trends in coal production and coal cleaning.
-------
A few washing plants located at river loading sites are
served by railroads with raw coal from the mines and dispose
of the refuse near the plant.
Coal screening and crushing plants are sited at widely
scattered locations wherever coal may be used, particularly
at coke plants, coal yards, power plants, and industrial
plants. They are also found at all mine loading sites.
Table 3-1 gives locations of major plants.
Siting Considerations
Siting of coal preparation plants is based on the
following considerations:
a. Length of haul. Optimum location is at shortest
possible distance from the mine.
b. Access to transportation by railway or barge.
c. Water supply. The plant must be provided with
substantial amounts of water from wells, streams,
or impoundments.
d. Suitable terrain. Level areas are required for
thickeners and slurry ponds; large areas must be
suitable for refuse disposal.
Transportation of Raw Material
A shaft mine discharges coal directly into the plant
without intermediate transportation.
Coal is also delivered directly from the mine by belt
conveyor or mine cars when the plant is adjacent to the mine
mouth.
3-7
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Table 3-1. LOCATION OF COAL WASHING CAPACITY
BITUMINOUS/LIGNITE COAL PRODUCTION
State
Alabama
Alaska
Arizona
Arkansas
Colorado
Illinois
Indiana
Iowa
Kansas
Kentucky
Maryland
Missouri
Montana
New Mexico
North Dakota
Ohio
Oklahoma
Pennsylvania
Tennessee
Texas
Utah
Virginia
Washington
West Virginia
Wyoming
Total
Production
capacity
1974,
thousand tons
19,745
716
6,432
445
6,960
58,080
25,267
680
679
133,000
2,170
4,625
14,089
9,669
7,400
44,566
2,375
78,879
7,681
7,684
6,047
33,249
3,915
105,997
20,650
601,000
No.
operating
companies
36
1
1
4
11
14
12
7
2
338
12
3
5
3
5
73
7
220
46
2
10
69
3
222
14
•1,120
No.
washing
plants
21
3
36
9
2
69
1
2
1
20
64
5
5
43
1
106
1
389
3-8
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Central cleaning plants are served by trucks, which may
t'-
haul coal 20 miles from the mine, and by railcars, which
/
haul raw coal to the plant and then reload with clean coal.
"Overland" conveyors haul coal from the mine to the
plant over distances up to 10 miles. One installation moves
coal from mine to plant by pipeline in a water medium.
Transportation of Plant Products
Refuse from coal preparation usually is hauled to
disposal areas by trucks. It is sometimes moved to adjacent
valleys by belt conveyors and aerial tramways.
Prepared coal is removed from the plant by railway,
barge, and truck. A small part is transported by conveyors
to power plant stockpiles or to loading terminals for long-
distance shipment.
3.5 ECONOMICS OF COAL PREPARATION
The advantages of preparing coal vary with the seam
being mined, the type of mining, and potential markets.
Figure 3-2 demonstrates the improvements made in the coal
that could be mined from a coal seam by continuous miners in
Indiana, Pennsylvania. This illustration represents an
extreme case in coal mining and preparation. Large amounts
of slate in the ROM material result in a heating value (HV)
of 7580 Btu, which is too low for commercial sale. Rejection
of impurities produces a product containing 6.6 percent ash
-------
RAW COAL 100%
— -\
1
£!J
1 1
HASHING GRAVITY 1.6
1 1
1 1
"l
i
IAN COAL 54. 5X
^
1
REFUSE 45.5%
TOTAL
HHV % HEAT %
% BTU/LB ASH CONTENT _S_
RAW COAL 100.0 7560 48.4 7560 5.0
CLEAN COAL 54.5 13308 6.6 7253 2.2
REFUSE 45.5 675 98.5 307 8.36
Figure 3-2. Illustrative cleaning circuit.
3-10
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with a heating value of 13,300 Btu; such a coal is readily
marketable.
The capacity of a boiler is upgraded by use of high-
heat-content coal, offering indirect savings in capital
investment, operation, and maintenance.
The sizes of stockpiles at large points of consumption
are based on a required period of operation without replen-
ishment. This requirement can be easily translated into a
given amount of stored energy (Btu). Because a stockpile
containing high-Btu coal can be smaller than one containing
low-Btu coal, the costs of materials handling are lower. In
the case depicted in Figure 3-2, a given stockpile of ROM
coal would be 1.76 times larger than a pile of prepared coal
having the same total heating value. Rejects from a cleaning
plant are directly correlated to the ash produced in a power
plant. The rejects from a cleaning plant are much easier to
dispose of than is the ash from a power plant, and a sub-
stantial savings can be realized where disposal is done at
the cleaning plant. A power plant using the coal evaluated
in Figure 3-2 (45.5 percent reject) would be required to
handle 7.24 times as much ash if the coal were burned raw
rather than washed. Rejecting impurities at the mine
results in a direct freight savings.
3-11
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Two cases, illustrating use of raw and washed coal from
the same mine, are analyzed in Table 3-2. Case 1 asseses
the value of ROM coal that is shipped 200 miles to a power
plant and sold for $0.70/10 Btu. Case II assesses the
value of the ROM coal that is washed and shipped to the same
plant for the same price.
Coal preparation involves five different steps, com-
binations of which constitute the plant for a given mine.
Step 1 - Crushing/screening. This step involves no
quality improvement, merely sizing for raw shipment. Most
utility coal is prepared this way. If further preparation
is involved, a separation is made at 1/4-3/8 inch.
This step includes all coal shipped. Costs are less
than those of other steps, ranging from $0.15 to $0.30 per
ton.
Step 2 - Wet washing the +l/4-inch sizes. Approxi-
mately 78 percent of all cleaned coal is washed by this
means. Many plants use only this step, shipping the 1/4 x 0
size raw.
Cost of wet washing the +l/4-inch coal ranges from
$0.25 to $0.50 per ton of feed.
Step 3 - Wet washing 1/4-inch x 28M (28 Mesh). Although
not usually practiced elsewhere, this step is nearly always
used at large underground mines. Approximately 14 percent
of the cleaned coal is washed by this means.
3-12
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Table 3-2. COST ANALYSIS, RAW AND WASHED COALS
Case I - Raw coal to power pi ant. a
Purchase cost 1 ton (i°°°-x 758g Btu x $0'70 ) = $10.61
10 Btu
Freight 200 miles (1 ton x 200 Mi. x $0.009b) = 1.80
Stockpile cost0 = 1.20
^.'
Ash disposal (45.5% x $3.80°) = 1.73
$15.34
Actual cost of energy at bunker ^x 7580 = ^-^/lO6 Btu
Case II - Washed coal to power plant.
Purchase cost 1 ton ROM (200° x 1331° * °'545 x °-70) = $10.15
106
Freight 200 miles (0.545 x 200 x 0.009) = 0.98
Washing cost = 1.60
Refuse disposal (0.455 x $1.20C) = 0.54
Stockpile cost (1.20 x 0.545) = 0.65
Ash disposal (3.80 x 0.545 x 6.6%) = 0.13
$14.05
Actual cost of energy at bunker (^ = $0-97/1()6 Btu
a For this analysis the HV is below acceptable values. The
price is below mining cost.
Typical Midwest unit train rate, 200 MM ton mi/yr.
c Typical average cost.
3-13
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Cost of this process ranges from $0.40 to $0.70 per ton
of feed.
Dry cleaning of the 1/4 x 0 coal with air tables accounts
for only 5 percent of all coal cleaned. It is sometimes
accompanied by prethermal drying.
Cost of dry cleaning is between $0.20 and $0.40 per ton
of feed. Thermal drying involves an additional cost.
Step 4 - Wet washing the 28M x 0, the least common
method, is used with only 3 percent of the coal and is
usually restricted to large deep mines equipped with con-
tinuous miners.
Costs range from $0.40 to $0.80 per ton of feed.
Step 5 - Thermal drying is nearly always restricted to
1/4 x 0 size coal, the exceptions being applications to
predry coal for screening prior to cleaning on air tables.
Cost of drying ranges from $0.60 to $1.20 per ton of
feed.
Costs for each step apply only to that portion of the
feed that is affected, as indicated in Tables 3-3 and ^-4.
Costs of coal preparation are dependent on screen analysis
and amount of rejects as well as efficiency of operation and
design/condition of plant.
The cost of processing in each step shown in the tables
is the average of the cost ranges listed above. Table 3-3
3-14
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Table 3-3. ILLUSTRATIVE PREPARATION COSTS,
EASTERN KENTUCKY COALS
Size
Raw coal
+ 1/4 in.
1/4 x 28M
28M x 0
Percent of
total coal
100.0
51.1
36.2
12.7
100.0
Cost, $/ton
screening
0.225
washing
0.375
0.55
0.60
Percent
recovery
100.0
75.0
78.6
80.4
Percent of
clean coal
38.3
28.5
10.2
77.0
Drying
cost, $/ton
0.90
0.90
Cost of
preparation,
$/ton
0.225
0.191
0.199)
0.256)
0.076)
0.090)
1.037
u>
M
CT.
Cost of preparation/ton of clean coal = $1.037 — 0.77 = $1.34/ton
-------
portrays coal from eastern Kentucky rained by conventional
methods; Table 3-4 portrays coal from southern West Virginia
mined by continuous mining methods.
3-16
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Table 3-4. ILLUSTRATIVE PREPARATION COSTS,
WEST VIRGINIA COALS
Size
Raw coal
+ 1/4 in.
1/4 x 28M
28M x 0
Percent of
total coal
100.0
15.0
65.7
19.3
100.0
Cost, $/ton
screening
0.225
washing
0.375
0.55
0.60
Recovery
100.0
41.0
68.1
69.1
Percent of
clean coal
6.1
44.7
13.4
64.2
Drying cost,
$/ton
0.90
0.90
Total
preparation
cost, $/ton
0.225
0.056
0.361)
0.402)
0.116)
0.120)
1.280
Cost of preparation/ton of clean coal = $1.28 ^ 0.642 = $1.99/ton
-------
4.0 PROCESS DESCRIPTION
As it leaves the mine, coal varies widely in size, ash
content, moisture content, and sulfur content. These are
the characteristics that can be controlled by preparation.
Sizes range upward to that of foreign materials, such
as a chunk of rock that has fallen from the mine roof or a
metal tie; large pieces of coal from a very hard seam are
sometimes included.
Ash content ranges from 3 to 60 percent at different
mines. Most of the ash is introduced from the roof or
bottom of the mine or from partings (small seams of slate)
in the coal seam. This ash, called extraneous ash, is
heavier than 1.80 specific gravity. The remaining ash is
inherent in the coal. The density of the coal increases
with the amount of ash present.
The moisture content of the coal is also of two types.
The surface moisture, that which was introduced after the
coal was broken loose from the seam, is the easier to
remove. This moisture is introduced by exposure to air, wet
mining conditions, rainfall (in stockpiles), and water
sprays. The remaining moisture, called "bed", "cellular,"
or "inherent" moisture, can be removed only by coking or
4-1
-------
combustion. This moisture was included during formation of
the coal.
Foreign materials are introduced into the coal during
the mining process, the most common being roof bolts, ties,
car wheels, timber, shot wires, and cutting bits.
Sulfur in coal occurs as sulfates, organic sulfur, and
pyrites (sulfides of iron). The sulfates usually are present
in small quantities and are not considered a problem. Organic
sulfur is bound molecularly into the coal and is not remov-
able by typical coal preparation processes. Pyrites gener-
ally are present in the form of modules or may be more
intimately mixed with the coal. Coal preparation plants
remove only a portion of the pyritic sulfur; therefore the
degree of sulfur reduction depends on the percentage of
pyrites in the coal, the degree to which this is intimately
mixed with the coal, and extent of coal preparation.
All the materials described above are combined with the
coal to form the run of mine (ROM) feed. Coal, as referred
to above, denotes the portion of the feed that is desired
for utilization.
4.1 CAPABILITIES OF COAL PREPARATION
Coal preparation processes can improve the ROM coal to
meet market demands, as limited by the inherent characteris-
tics of a given coal.
4-2
-------
The top size of the ROM can be reduced, to any size
specified, although control of the varying size increments
can be poor, dependent on the amount of crushing required.
No practical technology is known for increasing the sizes of
coal as mined.
All extraneous ash can be removed. The limiting
factor for removal of the remainder is an economic one. The
percentage of rejects of coal must not reach a point that
precludes a profit on the operation. The coal from better
seams can be processed to a reasonable ash content with few
rejects. That from a poor seam will be unable to match the
ash content without excessive losses. The optimum level of
removing the inherent ash sometimes depends upon the percent-
age of the refuse material having specific gravities of 1.3
or lower.
Although inherent moisture cannot be changed, the
surface moisture can be reduced to any level that is economi-
cally practicable. Considerations include the possibility
of reexposure to moisture during shipment and subsequent
storage and the fact that intense thermal drying creates
ideal conditions for readsorption of moisture.
The free sulfur in the coal is subject to removal only
by chemical treatment, which is not a coal preparation
process, or by combustion. The reason that the pyrites can
4-3
-------
be partially removed in washing processes is that they are
heavy enough to be removed with the ash. The processes can
remove only 30 to 60 percent of the pyrites, however, because
some pyrites are not broken free of the coal and are present
in a given piece in a quantity too small to increase its
weight enough to be rejected.
Foreign metals can be removed easily. Most wood frag-
ments can be removed, although a few small pieces of wood
cause no particular harm because they are combustible.
4.2 APPLICATION OF CLEANING PROCESSES TO SIZE INCREMENTS
Different types of mechanical cleaning apparatus are
required for cleaning of coals in different size ranges.
Coal larger than 8 inches is usually crushed to a smaller
size; when lump coal is required, the large fraction is
cleaned by slate pickers. The nominal size ranges and the
applicable cleaning equipment are listed in Table 4-1.
Table 4-1. COAL SIZE RANGES FOR CLEANING EQUIPMENT
+ 8 inches
8 x 1/4
1/4 x 48M
48M x 0
Picking tables
Heavy media bath or drums
Jigs
Diester tables
Heavy media cyclones
Air tables
Froth flotation
Use of thermal dryers is usually restricted to the two
smaller size fractions. Occasionally the + 1/4-inch frac-
tion is dried to permit screening.
4-4
-------
4.3 COAL SIZING
The first operations performed on ROM coal are removal
of tramp iron and reduction of size to permit mechanical
processing. The schematic of coal sizing circuit is shown
in Figure 4-1.
The ROM coal is first exposed to a high-intensity
magnet, usually suspended over the incoming belt conveyor,
which pulls the iron impurities out of the coal. This
magnet sometimes follows the breaker but always precedes a
screen-crusher.
The coal then goes to the breaker, which is a large
cylindrical shell with interior lifting blades; the shell is
perforated with holes (2- to 8-inch diameter) to permit
passage of small material. The breaker rotates on a hor-
izontal axis, receiving material in one end, tumbling it as
it passes through, breaking the soft material (coal), which
passes through the holes in the shell, and permitting the
hard, large, unbroken material to pass out the rear. The
small material (-4 inches) goes to the cleaning plant, and
the large rejected material falls into a bin to be hauled
away.
Various types of crushers are available for coal
crushing. The hammermill, shown in Figure 4-2, and the
rotary breaker, shown in Figure 4-3, are most commonly used.
4-5
-------
CAR DUMP
A
TRUCK DUMP
A
A FUGITIVE
DUST
.R. CAR
LOADING
A EMISSION POINTS
BARGE
LOADING
A
Figure 4-1. Coal sizing circuit.
4-6
-------
Figure 4-2. Hairanermill.
Figure 4-3. Rotary breaker,
4-7
-------
An alternate flow directs the ROM coal to a scalping
screen, from which the oversize material (+ 4 inches) falls
to a crusher, where it is reduced to -4 inches and is
recombined with the screen underflow for transportation to
the cleaning plant. This system is used more than the
breaker but is somewhat vulnerable to large pieces which
pass through the crusher and must be removed in a later
process. The crusher most commonly used for this purpose is
a heavy-duty single roll with tramp iron protection.
Double rolls are more difficult to maintain in this
heavy service, are more expensive, and offer no particular
advantage. Slow-speed hammermills or impactors are more
difficult to maintain, and jaw crushers have not been
required.
The raw coal is sometimes stored, prior to washing, to
allow optimum scheduling of mine and plant operations. Open
storage is the most common; silos are also used.
At mines using unit train shipment, prepared coal is
stored to accumulate enough to fill a train. For this
purpose, silos are used most often to prevent accumulation
of moisture and exposure to wind. Some open storage is also
practiced. At other mines, cars or barges are loaded
directly as the coal is processed, received, and shipped
each day.
4-8
-------
4.4 PNEUMATIC CLEANING
Pneumatic cleaning devices, or air tables, are applied
to the small fractions (-3/8 inches). In these devices
currents of air flow upward through a perforated bottom
plate over which a layer of coal passes. The extreme fines
are entrapped in the air and must be recaptured by cyclones
and bag filters for return without quality improvement. As
the coal reaches the end of the tables, the bottom layer is
heavy (high-ash) material, a center layer is medium-weight
coal and bone (high-ash), and the top layer is coal (low-
ash) . The middle layer must be incorporated with the refuse
(and rewashed) or with the coal. A typical pneumatic
cleaning circuit is shown in Figure 4-4. The cross-sec-
tional view of an air table is shown in Figure 4-5.
The efficiency of these devices is poor. Their ability
to remove ash is limited to 2 to 3 percent, regardless of
how much is present. These devices represent the lowest
capital investment of all cleaning devices, and they entail
no problems of water supply and disposal.
The incoming coal must be screened, and, because feed
to the tables must be dry, thermal drying of the raw feed is
required at some plants. The thermal dryers, in turn,
require cyclones and scrubbers for control of particulate
emissions. Thermal dryers are fired with coal, oil, or gas.
4-9
-------
TO LOADING OR WET CLEANING
R
i/ruT TO
Vtnl IU
ATMOSPHERE
^E
.X^s
BAG _.._
FILTER\/ \
e. A j/o •< •
AW 2 ^ 0
H
SURGE
BIN i 1 »
Y100 M ^
DRYING
0_ CHAMBER
nnTM/vpv A T"
f — i „ COMBUST.
O"1 p CHAMBER
^^MBUST. AIR
A
rt
^ 1/4 X 3^b M
\ /CYCLONE
/ • > ^ /o v n
r ' 3/o A U j
j k
r ?/ft ^ n
A^
j^32^™
R
A EMISSION POINTS C/l
j
— -
F
\
*
i
--
^"•*N
R
g VENT TO
i * AlMOSPHtKL
SCRUBBER
\S
1 — , 1 , SLURRY TO
1 PONDS
/CYCLONE
j
2 X 325M , ^
1 SCREEN
^Ci?^^ 2 X 3/8 ^
V
' »
sc
in
CM
X
co
CO
^r---— -"^— ^^
^^ "™"™™ "^1 ! P
~j AIR TABLE U "
'
1 '
REFUSE
^7 BIN
STACK EMISSIONS
Figure 4-4. Pneumatic cleaning circuit.
4-10
-------
CLEAN COAL
! DUST HOOD
MIDDLINGS
AIR LOC
FEED BIN
MOTOR
SHAKER UNIT
SPEED REDUCER
AIR DUCT
DAMPER
Figure 4-5. Air table.
4-11
-------
4.5 JIG-TABLE WASHING
Jig-table washing plants are thus named because jigs
are used to clean the +l/4-inch increment and Diester tables
to clean the 1/4 inch x 28M increment. Froth cells and/or
thermal dryers may be used in conjunction with this equip-
ment. Figure 4-6 shows a coal cleaning circuit with jig
table. The air-pulsated coal jig is shown in Figure 4-7,
the Deister coal washing table is shown in Figure 4-8.
The raw coal, restricted to sizes smaller than 8
inches, is separated on a wet screen (usually 1/4-inch
mesh). The large-sized increment goes into the jig; the
remaining coal is sent to a separate cleaning circuit. The
coal is dewatered on screens and in centrifuges, crushed to
the desired size, and loaded. The jig makes the "equivalent"
gravity separation on the principles of settling in rising
and falling currents. The small-sized coal (-1/4 inch) is
combined with the proper amount of water and distributed to
the tables, where the refuse is separated from the coal.
The refuse is dewatered on a screen and discarded. The
clean coal is dewatered on a sieve bend (a stationary
gravity screen), where the extreme fines are removed and
discharged into a centrifuge for final dewatering and
removal of the fines. The clean coal (+28M) is then loaded
or conveyed to a thermal dryer. The Diester table is a
4-12
-------
REFUSE 4X0
yjCRUSHER
1/2 X 0
t ^1
REFUSE BIN (1) "*[
. THERMAL
1 ->| DRYING
J PLANT
I
(1) TO WATER CLARIFICATION
A POINTS OF EMISSION
1/2 X 0
1/2 X 0
CLEAN COAL LOADING
OR STORAGE
Figure 4-6. Jig table cleaning circuit.
4-13
-------
Figure 4-7. Air-pulsated jig.
Figure 4-8. Deister table.
4-14
-------
flat, "riffled" surface, approximately 12 feet square, which
oscillates perpendicular to the "riffles," in the direction
of the flow of coal. The heavy rejects are discharged off
one end of the discharge side of the table, the light coal
is discharged from the opposite end, and the "middlings" are
distributed between.
The slurry produced, along with the fines, requires
clarification before recirculation is feasible. Clari-
fication is described in Section 4.7 and portrayed in
Figure 4-11.
4.6 HEAVY-MEDIA WASHING PLANT
In a heavy-media washing plant, all the cleaning is
done by flotation in a medium of selected specific gravity,
maintained by a dispersion of finely ground magnetite in
water. The plant is depicted in Figure 4-9. A schematic of
a typical heavy-media cyclone is shown in Figure 4-10.
The incoming raw coal is separated at 1/4 inch on an
inclined screen. The "overs" proceed to a flat "prewet"
screen, where the fine dust particles are sprayed off from
the +l/4-inch coal. This increment is discharged into a
heavy-medium vessel or bath, where the refuse is separated
from the coal. The refuse is discharged to a "refuse rinse"
screen, where it is dewatered. The freed medium is -divided
into two parts, one returning directly to circulation via
the heavy-medium sump and the other pumped to magnetite
4-15
-------
4 X 1/4
A
"CTlCRUSHER
(P)
3/4 X 0
[" THERMAL" "!•*
DRYING PLANT (ALTERNATE
u J •
3/4 X 0
11/2X0
(J) COARSE MAG. SEPAR. CLEAN COAL
TO REFUSE BIN
(K) FINE MAG. SEPAR.
(L) CENTRIFUGE
A) RAW COAL SCREEN
B) PRE WET SCREEN
C) REF. RINSE SCREEN (M) CENTRIFUGE
D) COAL RINSE SCREEN (N) CENTRIFUGE
E) SLURRY SCREEN (P) CRUSHER
(F) REFUSE RINSE SCREEN (R) CYCLONE
(6) SIEVE BEND (S) LIGHT MEDIA SUMP
(H) HVY. MEDIA BATH (T) HEAVY MEDIA SUMP
(I) HVY. MEDIA CYCLONE (V) HEAVY MEDIA SUMP
A EMISSION POINTS
(1) TO WATER CLARIFICATION
A
LOADING OR STORAGE
Figure 4-9. Heavy-media cleaning circuit,
4-16
-------
6"!
Figure 4-10. Heavy-media cyclone.
4-17
-------
recovery. The refuse is discharged from the screen for
disposal. The coal is discharged from the washer to a coal-
rinse screen, where the coal is dewatered and the medium is
treated as from the refuse screen. The clean coal is then
centrifuged, crushed, and loaded. The fine coal (-1/4 inch)
from the raw coal screens is combined with magnetite and
water and pumped to a heavy-media cyclone, where the refuse
is separated from the coal by cyclonic action. The medium
for this use is different from the one used in the heavy-
media vessel in that the magnetite is finer and the effec-
tive specific gravity is different. The refuse is dewatered
and the medium is recovered, as in the coarse coal section.
The coal is discharged over a sieve bend and then proceeds
to a centrifuge for final dewatering prior to transfer to a
thermal dryer or to loading.
Because the magnetite recovered from the rinse screens
is diluted by sprays, it is processed in magnetic separators
for recovery of the solid mineral. Each washer (bath and
cyclone) retains its own recovery system, which includes
sumps, pumps, and magnetic separators. The separator is a
shaft-mounted steel drum containing an interior fixed
magnet. The cylinder rotates within a vessel containing
coal slurry and magnetite, retrieving solid magnetite from
the slurry by virtue of the magnetic qualities of the
magnetite and the magnetic field within the drum.
4-18
-------
The effluent from the, centrifuges contains -28M coal,
broken from larger pieces of clean coal. This material is
thickened in a cyclone, deslimed on a screen, and centri-
fuged prior to loading.
4.7 WATER CLARIFICATION PLANT
The water clarification plant receives all the slurry
from the washing plant, separates the 48M x 0 fraction for
cleaning, and returns the water for reuse. A typical
clarification plant is shown in Figure 4-11. The 48M x O
fraction flows to froth flotation cells, where it is mixed
thoroughly with a reagent (light oil). The coal accepts a
coating of oil and floats off the top of the liquid to a
disc filter, where the excess water is drawn through a
fabric by a vacuum. The water is recirculated to the
washery, and the fine coal is transported to loading or to
a dryer. Figure 4-12 shows the froth flotation unit.
The refuse does not accept the oil coating and sinks,
to be removed with most of the incoming water to a static
thickener. The thickener is a large, circular, open tank,
which retains the water long enough to permit the particles
of refuse to sink to the bottom. Clarified water is removed
from the surface by "skimming troughs" around the perimeter
of the tank and is recirculated to the cleaning plant.
The tank is equipped with a rotating rake, which rakes
the fine refuse from the bottom of the tank to the center of
4-19
-------
ASM X 0
RAW COAL
REFUSE
28M X 0
SLURRY
48 X 28M^_ RETURN TO
/CYCLONE
H^TjJFLOTATION CELLS
CLEAN
WASHING CIRCUIT
0
COAL
DISC FILTER
COAL CLARIFIED WATER
RETURN TO THERMAL RETURN TO
DRYER OR LOADING CIRCUIT
a
>-
o
is
cc.
L
DISC FILTER
a
TO STREAM
REFUSE
Figure 4-11. Water clarification circuit.
4-20
-------
I
tO
FEED
ttr »tt»TT T Y T
CONCENTRATE II CONCENTRATE
FEED BOX
INTERMEDIATE BOX
PULP FLOW
DIRE'CT CONNECTION
DISCHARGE BOX
Figure 4-12. Froth flotation unit.
-------
the tank, where it is collected by a pump and transferred to
a disc filter. The filter removes part of the water for
recirculation and discharges the solids as refuse.
4.8 THERMAL DRYING
The clean coal from various wet cleaning processes is
wet and requires drying to make it suitable for transpor-
tation and final consumption. Thermal drying is employed to
dry the wet coal.
Drying in the thermal dryer is achieved by a direct
contact between the wet coal and currents of hot combustion
gases. Various dryers marketed by different manufacturers
work on the same basic principle.
The most common types of dryers are shown in Figures
4-13 through 4-16.
The fluid-bed dryer is shown in Figure 4-13. The dryer
operates under negative pressure in which drying gases are
drawn from the heat source through a fluidizing chamber.
Dryer and furnace temperature controllers are employed in
the control system to readjust the heat input to match the
evaporative load changes.
The multilouver dryer, shown in Figure 4-14 is suitable
for large volumes and for the coals requiring rapid drying.
The coal is carried up in the flights and then flows down-
ward in a shallow bed over the ascending flights. It gradu-
4-22
-------
DUST COLLECTOR
DUST
DUST SCREW CONVEYOR-
SETTLING CHAMBER
DISCHARGE VALVE
AUTOMATICALLY CONTROLLED
FEED AND DISCHARGE GATES
FAN STACK
.FAN
FEED
ROLL FEEDER
PRODUCT
TEMPERING AIR DAMPER'
BY-PASS STACK
Table 4-13. Fluid-bed dryer.
4-23
-------
Figure 4-14. Multilouver dryer
Figure 4-15. Cascade dryer.
4-24
-------
ALTERNATE VENT
WET SCRUBBER
(IF REQUIRED)
C-E RAYMOND FLASH DRYING
ALTERNATE ARRANGEMENT
FOR VERY FINE WET COAL
DRYING COLUMN
DRY COAL DISCHARGE
FROM AIR
AUTOMATIC
DRY DIVIDER
DRY RETURN
WET FEED-:
MIXER
DRY COAL CONVEYOR
WET FEED CONVEYOR
WET FEED BIN
GATE
WET FEEDER
DOUBLE FLAP VALVE
TEMPERING AIR DAMPER
Figure 4-16. Flash dryer.
4-25
-------
ally moves across the dryer, a little at each pass, from the
feed point to the discharge point.
The cascade dryer is shown in Figure 4-15. The wet
coal is fed to the dryer by a rotary feeder; as the shelves
in the dryer vibrate, the coal cascades down through them
and is collected in a conveyor at the bottom for evacuation.
Hot gases are drawn upward through and between the wedge
wire shelves.
The flash dryer is shown in Figure 4-16. The term
"flash" is derived from the fact that the wet coal is
continuously introduced into a column of high-temperature
gases and moisture removal is practically instantaneous.
4.9 EMISSION SOURCES AND CONTROL DEVICES
All emission sources are subject to opacity regulations
and two are subject to particulate count regulations. The
pneumatic cleaning plants generate emissions from the air
tables and are subject to one standard; thermal dryers have
an emission stack and are subject to another standard.
Emission points in the various plant sections are shown
in the appropriate diagrams. The most commonly used control
devices for each emission point are keyed as follows:
(1) Cyclone
(2) Scrubber
(3) Spray
(4) Baghouse or fabric filter
(5) Enclosure
4-26
-------
These parenthetical numbers are used in the following
tabulation relating emission sources and their controls.
Coal Handling Facilities
RR and mine car dumps - 2,3,5
Truck dumps - 2,3,5
Storage bins and silos - 4,5
Breakers and crushers - 3,4,5
Conveyor transfer points - 3,4,5
Screens - 4,5
Trucks, RR car, and barge loading stations - 1,4,5
Pneumatic Cleaning Plant
Surge bin -4,5
Thermal dryer stack (if present) - 1,2
Vibrating screens -4,5
Air tables 1,4,5
Crusher - 3,4,5
Jig-Table Washing Plant
Screen -4,5
Loading facility - 2,3,5
Thermal dryer (if present) - 1,2
Heavy-Media Washing Plant
Screen -4,5
Loading facility - 2,3,5
Thermal dryer (if present) - 1,2
4.10 CONTROL DEVICES, THEIR CAPABILITIES AND EFFICIENCIES
The various control devices are employed singly or in
combination at each emission point according to the tem-
peratures and volumes of flue gases, the degree of contam-
ination, and the applicable regulations.
Cyclone sizes range from 2 inches to 18 feet in diameter,
the smaller being applied in groups that use a common inlet
4-27
-------
and dust hopper. A cyclone serves as a primary separator
because its efficiency is limited to particles larger than
44 microns. The efficiency is a function of the particle
mass, inlet velocity, and the radius of the cyclone, in-
creasing with smaller radii and higher inlet velocities.
Pressure drop also increases with velocity.
Some variables of cyclone design are indicated in Table
4-2.
Table 4-2. CYCLONE VARIABLES
Min.
Max.
Cyc.
dia.
2 in.
18 ft.
Capacity,
cfm
10
25,000
Inlet
velocity,
fps
15
75
Pressure
drop, in.
0.5
6.0
Smallest
size
collected
@50% eff . , y
10
200
Cyclones are lined with refractories or water-jacketed
for processing of hot gases and are fabricated of alloy
steels for processing of corrosive gases.
Scrubbers are enclosures in which dust particles are
agglomerated in small drops of water, which then flow from
the vessel. In impingement-type scrubbers, agglomeration is
accomplished by driving the dust-laden gas at high veloc-
ities onto flooded targets. Wet centrifugal separators pass
the dust-laden air through a zone of high-velocity water
droplets. Wet dynamic precipitators cause the dust to
4-28
-------
impinge on wetted fan blades. A venturi scrubber acceler-
ates the dust-laden air through a venturi throat, where it
atomizes the water to form droplets.
Scrubbers lose efficiency rapidly in collecting par-
ticles below 5 microns. Efficiency loss is proportional to
the pressure drop or power consumption. The major scrubber
variables are presented in Table 4-3.
Table 4-3. SCRUBBER VARIABLES
Scrubber
type
Impingement
Centrifugal
Dynamic
Venturi
Water
consumption
per
1,000 cfm
gas , gpm
3-5
4-10
1
3-15
Pressure
drop,
in.
6-8
2-6
1
12-60
Capacity,
cfm
90,000
140,000
25,000a
140,000
Max.
efficiency,
% (Particle
size range)
95
(1-5 micron)
90
(2-5 micron)
95a
(2-5 micron)
98
(submicron)
Estimated
Scrubbers are used for control of thermal dryer emis-
sions because they can accommodate gas temperatures up to
250°F and are insensitive to the heavy moisture content.
Orifice meters are commonly used for measuring the scrubber
water flow rates.
4-29
-------
Table 4-4 presents the flow rate variables for six
common orifice sizes.
Table 4-4. ORIFICE FLOW RATES
Pressure
lb/in2
20
30
40
50
60
Water flow, gpm
diameter of orifice, in.
3/16
3.0
3.6
4.1
4.6
5.1
1/4
5.2
6.4
7.4
8.2
9.0
5/16
8.1
10.0
11.5
12.8
14.0
3/8
11.7
14.4
16.5
18.5
20.2
7/16
15.8
19.5
22.4
25.0
27.5
1/2
20.1
25.4
29.4
32.9
36.0
Baghouses or fabric filters are applicable for capture
of fine particles of dust when the gases are at moderate
temperatures, contain no sticky materials, and are nonex-
plosive.
The dust-laden stream is passed through a finely woven
or felted fabric on which a layer of dust serves as the
filtering medium. As this dust layer thickens, the bag is
"shaken" mechanically or by abrupt pressure changes to
remove a portion of the filter cake.
The filter is usually in the shape of a circular
closed-end cylinder 5 to 12 inches in diameter and up to 30
feet long. Smaller filters are used to control emissions
from bin and silo openings. The size of a filter instal-
lation depends on the amount of air and dust to be filtered,
4-30
-------
The ratio of air to filter cloth area depends on several
variables; different services require different ratios or
filtering velocities. The guidelines used for filtering of
coal dusts are ratios of 6/1 for high dust loadings and
elevated temperatures, progressing up to 8/1 for general
dust loadings. Pressure differentials range from 2 to 10
inches w.g.
Fabrics are selected on a basis of chemical resistance,
tensile strength, temperature resistance, weave, and elec-
trostatic characteristics. Operating temperatures of some
common fabrics are shown in Table 4-5.
Table 4-5. OPERATING TEMPERATURES
Cotton
Wool
Dacron
Glass
Nylon
Orion
Maximum operating temperature, °F
Long term
160
200
275
500
200
240
Short term
200
250
300
650
250
290
The mechanisms for cleaning the bags include hand
shaking, reverse air jets, mechanical rappers, and bag
shakers. Since a bag is out of service while it is being
cleaned, the installation must be designed to accommodate
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this loss of service. The bags are fastened at the top,
with quick-release fastenings to permit easy bag replace-
ment, and are suspended in the dusty environment. A vacuum
is introduced in the bag, pulling the air through the fabric
bag for release through the top, leaving the dust collected
on the exterior of the bags. In some installations the
dusty air flows through the interior of the bag.
The baghouse containing the fabric filters may be
square, rectangular, or circular and is constructed of
metal. The vertical dimension exceeds the length of the
bags, and the top or roof is flat. The open bottom is
connected to a conical or pyramidal section, which receives
the dust shaken from the bags for removal by an airlock
feeder valve. The baghouse is self supporting, with suit-
able walkways for access.
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5.0 INSTRUMENTATION AND RECORDS
Instrumentation for measurement of process parameters
and methods of recording these measurements are important in
controlling and predicting process emissions. The accuracy
of predicting emissions can be directly related to the
degree of sophistication of the instrumentation and record-
keeping at the plant. The instrument reading provides an
instantaneous indication of operating conditions; detailed
records will provide a basis for reviewing plant operations
over an extended period.
The flow of coal through the preparation equipment is a
constant function of the amount of coal input at the feeder
conveyor. Overloading of the feeder conveyor will result in
overloading of the equipment following it. Most of the
equipment incorporates an indicator showing instantaneously
the load being processed.
In older plants most equipment control is of the ON-OFF
type. In case of overloading, a red light comes on and the
equipment is automatically stopped. These ON-OFF lights do
not indicate in advance a potential malfunction or overload
and are not helpful for indication of emissions.
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The newer and larger plants generally incorporate a
central control room with automated instrumentation showing
the instantanous loading and other major parameters such as
pressure drop and temperature of the gases. The monitoring
records of required process parameters are also maintained
in this central control room.
When the instruments indicate abnormal operating
conditions, the operator can take action to prevent possible
major equipment malfunction or plant shutdown. The use of
instrument readings for predicting plant emissions is
discussed in Section 8.0.
5.1 PROCESS INSTRUMENTATION
Instrumentation in the coal preparation plant is
relatively simple in comparison with instrumentation at
other process industries. The instruments generally found
on coal preparation equipment are described below:
Conveyor
The conveyors are driven by electric motors; the
current drawn by the conveyor motors varies directly with
the conveyor load. The ammeters located in the control room
indicate the instantaneous current drawn by the conveyor
motors. When excessive current is indicated, conveyor and
equipment loading should be investigated.
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Some conveyors are also equipped with load, meters.
These meters indicate the percent of rated load carried by
the conveyor at a particular instant. Ammeters and load
meters give basically similar indications.
Crushers
The crusher load is directly proportional to the feed
rate and feed sizes. The crusher is driven by an electric
motor. The ammeter for the motor is generally located in
the central control room. Indication of excessive current
should be investigated to determine the cause.
Screens
In addition to the load-current ammeters, the screens
may be equipped with pressure gauges indicating the pressure
of water to the sprays. The various correct combinations of
load current and spray pressure should be established during
performance tests for reference during periodic inspections.
The increase in load tiurrent would mean increased screen
loading; this should be matched by increased spray water,
which will be indicated by the pressure gauge.
Air Tables
In general, the new air table installations will be
equipped with instruments to indicate the load current,
pressure drop across the air table, and pressure drop across
the control equipment. The load current is indicated by the
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ammeter; pressure drops are indicated by the pressure
gauges. These instruments can be located in a central
control room. The correct combinations of these parameters
should be established during performance tests for future
reference.
An excessive pressure drop across the air table means
a higher percentage of fine coal in the table feed. This
will also result in an increased load on the control device.
The pressure drop across the control device should be
matched to meet the increased particulate loading.
Thermal Dryers
Thermal dryers are equipped with instruments to in-
dicate the feed rate and exit gas temperature. The exit gas
temperature is continuously recorded and monitored. In the
case of thermal dryers with venturi scrubbers, scrubber
water supply pressure and pressure loss in the venturi
constriction are also continuously monitored. The monitoring
aspects are discussed under records in Section 5.2.
The thermal dryer feed rate indicates the quantitative
loading; however, this may not be useful for predicting the
emissions. Emissions from the thermal dryer would depend on
the moisture and fine-coal percentage of the feed.
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5.2 RECORDS
The NSPS require the continuous monitoring of the flue
gas temperature at the exit of the thermal dryer, pressure
of the water supply to the venturi scrubber, and pressure
loss in the venturi constriction. A record of these parameters
will be available at the plant for inspection.
Other records, though not required under NSPS, showing
the plant feed rates and equipment malfunction and shutdown
should be inspected to determine the plant's emissions
between inspections.
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6.0 START-UP, SHUTDOWN, AND MALFUNCTIONS
Emissions that occur during normal plant start-ups and
shutdowns are exempted by regulations. The following
sections discuss the possible causes of extended emission
upsets and precautionary measures for preventing them. The
primary emission sources are the air table and the thermal
dryer, and, in some cases of malfunction, their control
devices. The secondary emission sources are more numerous,
less susceptible to upset, and more easily corrected. These
sources are screens, breakers, crushers, conveyor transfer
points, storage bins, loading and unloading stations, and
supporting equipment.
In this section, a brief discussion of emisssion during
plant start-up and shutdown is followed by analysis of
malfunctions that can occur in regular plant operation.
6.1 START-UP AND SHUTDOWN
A normal interruption during a shift, such as that
caused by car changes, lack of coal, or mechanical failure
of equipment, usually does not cause an emission upset
because the plant is kept running. The heat of the thermal
dryer is regulated, and the other emission sources will
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receive no coal to create dust. Upon resumption of coal
flow, the first coal encounters normal conditions.
In start-up at the beginning of a shift or after a long
breakdown, the period of adjustment is short, lasting only
until the flow of coal through the plant is complete. In
the starting sequence, each unit (or several) is brought on-
line at a time interval. The normal procedure, on automatic
starting, would energize all water pumps, air compressors,
and related dust control equipment before coal is received.
The thermal dryer should be up to temperature, and all
sprays should be operational. At a well-designed plant,
this sequence is interlocked, without recourse to bypass.
Some plants are built with selected interlocks; these
arrangements permit utilization of only certain sections of
the plant or operation around nonfunctional equipment.
Manual controls to allow bypassing of interlocks are common.
Improper use of bypass features is the most probable reason
for an emission upset during start-up of a plant with inter-
locks.
The shutdown procedure for some plants is automatically
executed in the reverse of start-up, with some variations.
This permits the plant to "empty" itself; more commonly, the
"stop" sequence is timed to a shorter period than is- re-
quired for traverse of the process circuit. In either
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event, the dust control equipment should be timed to con-
tinue operation after the coal feed is stopped, for a
period long enough to allow the equipment to run clean.
The coal preparation incorporates an emergency "stop"
button which halts all equipment instantly. This procedure
entails no particular ill effects, since everything (including
the thermal dryer) stops operating. However, if the incoming
coal is near the capacity of the circuits and a buildup of
dust has occurred in critical spots, a short emission upset
may occur on start-up.
6.2 CHANGES IN COAL FEED
Analysis of the incoming coal may change sufficiently
to create plant emission upsets. This is most likely to
occur at a central preparation plant that processes coal
from several mines and different coal seams. The second
most vulnerable plant is one that serves a large mine
producing from both conventional and continuous mining
sections, the conventional type producing finer coal.
Variable feed also can prevail at a plant receiving coal
from a stripping operation with auger production.
Blending the raw coal, either from multiple storage
units or by proportioned acceptance, will reduce the impacts
of variable feed. Multiple storage facilities, however, are
rare and very expensive; proportional feed is difficult and
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less positive as a control. Use of a single raw coal
storage silo can produce the same problem at intervals, as
can changes in surface moisture content caused by different
levels of spraying underground, wet mines, precipitation on
open storage piles, and exposure during transport.
In the discussions that follow, it is important to
remember that malfunctions occurring at many points in the
coal preparation circuit may be attributable, at least in
part, to changes in coal feed.
6.3 MALFUNCTION OF SUPPORT EQUIPMENT
Malfunctions of supporting equipment, usually mechanical
failure, can cause frequent or sustained interruptions of
plant operations. The most usual are listed below.
Breakdown of conveyor drives, crushers, chains, centri-
fuges, feeders, pumps, or screen cloths.
Blockage in bins or release of veil-chains or plates
into the coal flow.
Failure of magnetic protective equipment, permitting
introduction of large "tramp" iron into the feed.
Electrical accidents, inadequate power source, or
inadequate lightning protection.
Poorly controlled spraying, producing variable moisture
content (at dry cleaning plants).
Damage of ROM conveyor belt from tramp iron, misalign-
ment, or oversized rock.
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6.4 MALFUNCTIONS IN SOURCES OF FUGITIVE DUST
Malfunctions in dust-producing equipment are caused by
overload, poor maintenance or design, electrical failure,
accident, or improper operation.
Air Table
The air table is most adversely affected by a sharp
change in size distribution of the incoming coal to include
greater amounts of extreme fines. This shift permits over-
loading of the dust control equipment. Simple overloading
of the air table, which produces a similar condition, is
caused by malfunction of the proportioning feeder on the air
table or by desire of the operator to increase production.
Air seals on the table, if not properly maintained, will
become serious sources of fugitive dust emissions.
Thermal Dryer
The thermal dryer, like the air table, is subject to
particulate emission standards.
Overheating of a thermal dryer may be caused by failure
of a regulating valve (gas or oil fired) or other control
and usually will produce an "upset" plume. The "internals"
of dryers involve mechanical (sometimes moving) parts, which
are subject to wear and damage. The refractory lining also
is subject to wear and damage and is subject to scheduled
replacement.
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The second section of a thermal dryer is a large-
diameter cyclone, used to extract the particulate matter
larger than 300 M from the gas stream. This cyclone has no
internal working parts, but the refractory lining is subject
to wear. Volume of air, temperature, and pressure drop are
the chief criteria for satisfactory or normal cyclone
operation. Other causes of emissions are mechanical failure
of the discharge feeder and wearing of seals.
The last section of a thermal dryer is a scrubber, used
to remove the fine portion of coal (300 M x 0) from the air
stream. The scrubber may incorporate a bypass for emergency
use, which may be partially open and permit particulate
emission. The inspector should examine the bypass during
each plant inspection and should also examine records of
bypass use.
The venturi scrubber is the type most commonly used.
Its efficiency is a function of the volume, pressure drop,
and temperature of the contaminated air and the volume and
pressure of the scrubbing medium (water). Deviation from
established norms can be checked by reference to records of
previous plant inspections.
The inspector should examine the seals at manholes and
duct collars for tight fit and should check the device for
removal of solids and spent scrubbing liquids to ensure that
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it is not blocked partially open. With a "variable venturi"
type scrubber, the inspector must be provided with a record
of the "normal" setting. Water is introduced internally
through a nozzle or sprays, which, if blocked or inoperative
could affect a zone of the venturi adversely.
The moisture separators and/or demisters of a scrubber
installation may become blocked, or partially so, particu-
larly if they include a screen. Particular attention
should be given to "ball-bed", "packed tower," and "packed
bed" types of scrubbers, which incorporate a supplemental
internal feature that may become blocked or cause resistance
to the flow of gas or liquid.
Screens
Fugitive dust emissions occur at the screens when fine
coal is involved. The coal preparation plants generally use
three types of screens: grizzly, shaker, and vibrating.
Grizzly screens are used on ROM coal preceding a
crusher or loading a belt conveyor. They usually are served
by sprays but are sometimes enclosed. The doors, plates,
and seals of the enclosure are highly subject to damage by
pieces of metal or rock. Wet incoming material may cause
plugging of the branch air duct from the enclosure to the
dust collector, which should be sized to carry dust-laden
air, at the minimum pressure available, at a velocity of not
less than 4500 fpm.
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Shaker screens are used infrequently, rarely providing
a separation less than 2 inches (usually much larger). A
hooded enclosure may be found alongside the screen. Prin-
cipaj. malfunctions involve plugging, short-circuiting, or
improper sizing of the conveying ducts, damage to the hood,
or improper placement of the hood.
A vibrating screen is the most common separating device.
Many screens are flooded with water and constitute no dust
source. The "dry" screens usually make a separation at 1/4-
3/8-1/2 inch and create fugitive dust. Malfunctions involve
loose seals, damaged enclosures, open access doors, and
blocked or short-circuited air ducts.
Crushers
Crushers, an important source of fugitive dust, are
protected by sprays or dust collectors. A sudden appearance
of fugitive dust may be caused by blockage or short-cir-
cuiting of air ducts, broken enclosures or seals, or open
access doors. If operation of the crusher is changed, an
upset may occur. A hammermill will respond to higher speeds
with finer product and/or greater capacity, creating a new
situation for dust control. Introduction of a coal of soft
consistency also can introduce new problems.
Breakers are subject to the same types of malfunctions
described for crushers, caused by broken, loose, or mis-
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placed enclosures, blocked or short-circuited air ducts,
open access doors, and overloading. Similarly, change of
perforated plates to reduce the sizing or introduction of
coal from different seams can cause fugitive dust emissions.
Conveyor Transfer Points
Conveyor transfer points are sources of fugitive dust
when dry coal containing the 3/8 x 0 inch increment is
processed. If the material is larger than 3/8 inch or
surface moisture content exceeds about 9 percent, dust
emissions do not occur. The enclosure usually has an access
door, which may be removed or left open, thus short-cir-
cuiting the "pickup" air. Rubber seals or curtains also may
be removed or damaged. Airflow may be insufficient to
gather the dust. The duct carrying the dust-laden air away
may be blocked, broken, or poorly sized. A damper may be in
/
the wrong position, or the chute leading from the conveyor
pulley may be blocked, permitting spillage. The duct
should carry the volume of air at a velocity of 4500 fpm.
Proper conveying pressure may be unavailable because of
malfunction or overloading of the collecting device at the
duct terminal. Speeding or overloading of a conveyor may
cause an emission upset at the terminal. Reference to
earlier inspection reports will disclose any deviation from
the normal flow of coal at a given point. Most of the
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malfunctions described above are readily handled by main-
tenance and replacement of damaged components.
Storage Facilities
Storage bins or silos include several possible fugitive
dust sources. The feeder underneath a bin may be enclosed
in a structure similar to that at a belt conveyor transfer
point just described, and the same malfunctions may occur.
Most storage bins and silos are covered and are loaded
by the conveyor. The conveyor discharge has been discussed,
but a supplemental bin exhaust should be present to equalize
pressure inside against the volume of incoming coal. This
port is sometimes equipped with a bin vent filter, which can
become plugged because of infrequent filter changes or
exposure to water. The bin may also have ducts leading from
these vents to a central dust collector. The bin should be
exhausted at an air volume rate equal to twice the volume of
incoming coal. Emissions may occur if this amount of air is
not provided or if the lines from the bin are inadequate, as
discussed with respect to conveyors.
A third possible emission source is present on a few
silos, usually storing ROM, which have large openings
through the walls near the top and around the circumference
at spaced intervals. These openings may have doors, which
are normally closed to contain the coal within the silo.
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Coal is released upon operator demand or when the silos
become nearly full, flowing through the holes to open
storage around the silo. This operation can produce sub-
stantial fugitive dust emissions.
Loading and Unloading Stations
The points at which outgoing coal is loaded and in-
coming coal is received constitute significant sources of
fugitive dust emissions because of the large volumes of coal
that are handled, often without adequate controls. The
chutes, hoods, bins, and miscellaneous full or partial
enclosures involved in unloading and loading operations are
subject to the same malfunctions described earlier with
respect to similar equipment elsewhere in the plant:
passages are blocked or plugged, access doors are removed or
left ajar, seals are broken or faulty, metal components are
dented, corroded, or otherwise deteriorated. Essentially
simple structures or devices may be inoperable because of
damage that is undetected or ignored. The task of the
inspector is to note and record all actual or possible
points of dust emission requiring the attention of plant
operators. Certain points of the coal transfer operations,
however, are worthy of special note.
Unloading from railroad cars may involve the use of
retractable chutes, operated pneumatically, which often lose
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precision because of wear or erratic power supply. Con-
ventional loading of railroad cars is sometimes protected by
oil spraying, the effectiveness of which may be deteriorated
by broken or plugged sprays and lines, damaged pumps or
tanks, erratic pressure control valves, and insufficient oil
supply- Barge loading is by chute, retractable to a degree
but still permitting free fall of the coal into the barges.
In stockpile loading by conveyor, coal is discharged from a
conveyor high in the air and falls either through retractable
chutes or loading stacks. Loading stacks are hollow,
stationary columns, either of steel or concrete, reaching
from the ground to the belt conveyor discharge. They have
staggered partial openings at different elevations, extending
the entire length, to offer some protection from the wind
and to permit accumulation of the stockpile around the
exterior. If the closures are blocked in an open position,
adverse air currents may be generated.
In all of the loading operations, windbreaks are
essential for control of air currents. These should be well
placed with respect to prevailing winds, and must be well
maintained for maximum effectiveness.
The dust emission problems involved at stations for
unloading of the ROM coal naturally are similar to those at
loading points.
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Truck dump bins sometimes are partially enclosed.
Sheeting may be absent from these enclosures, either delib-
erately or by accident. Many such bins have no dust control
system. Any hooded dust control must allow for very high
airflow because of the high rate at which the air in the bir
is exhausted.
Stations for unloading of railroad cars are normally
housed, and the fugitive dust is controlled by sprays.
Those with dust-collecting hoods are subject to the mal-
functions described earlier.
6.5 MALFUNCTION OF CONTROL DEVICES
Malfunctions of control devices principally involve
scrubbers, cyclones, sprays, baghouses, and dust collection
systems. Scrubbers have been discussed in connection with
thermal dryers.
A cyclone should be installed to operate on prede-
termined volumes of particulate-bearing air at given tem-
perature limits, with a minimum stipulated recovery of
particles in the various size ranges. Recovery is deter-
mined by the shape of the cyclone and the volume flow
through it. This is true of all cyclones, whether single or
in clusters, large or small, hot or cold.
Detecting the cause of a malfunction will involve
isolating the circumstance that has changed since normal
operation was recorded.
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Air volume can be measured at the outlet of the cy-
clone. It may be low if the fan is worn, belts are loose or
broken, or intake area is no longer sufficient to pass
adequate air at the pressure available. Blockage anywhere
in the system is equally damaging.
Temperature can be measured at the cyclone inlet. If
it deviates from the design limits, the volume of air at a
given pressure will be incorrect. Temperature variations of
these proportions would probably reflect the introduction of
heated air.
Determining pressure drop "across the cyclone" requires
pressure readings before and after the device. Common
problems are a worn vacuum pump, loose belts, and an opening
in the duct following the cyclone. If the pressure is
constant at the fan, the pressure has increased downstream
from the cyclone or an accident has occurred within the
cyclone.
The shape of the cyclone can be changed by large dents,
fallout of the refractory liner, mechanical failure of the
feeder discharging solids at the bottom, and by blockage due
to accumulation of fire clay or wet fine coal on the in-
terior walls. In a wet-wall cyclone, the flow of liquid
down the interior walls may be inadequate to reach the
bottom, causing buildup on the interior. In cyclone clusters,
partial blockage of any of the several small units can
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reduce the flow of air. As with many of the processing
components, a change in analysis of incoming coal can cause
difficulty.
Spray systems in a coal preparation plant can range
from low-pressure "fish tails" or hollow-nozzle types to
high-pressure (300 psi) impingement types. A wetting agent
is occasionally used in the spray water. Appearance of
excessive particulate probably may be traced to one of the
following causes:
0 Introduction of more than normal amounts of dust.
0 Misalignment, damage, or plugging of spray heads
or header.
0 Damage of a control valve.
0 Plugging of a line filter or incoming line.
0 Wear or damage of pump or drive.
0 Lack of water.
0 Damage of sensor device or on-off switch.
0 Accumulations of ice in lines or spray heads.
The criteria for successful operation of fabric filters
are pressure drop across the baghouse, temperature of the
incoming air, and the volume of air per surface area of
filter fabric. Other possible causes of fugitive dust
emissions include the usual factors involving wear, damage,
looseness, plugging, or other impediments to effective
operation of fans, blowers, ducting, hoppers, and similar
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components. In addition, the inspector may check for the
following:
0 New bags pass fine particulate until they become
permeated and coated. If new fabric is used it
may not be compatible with the air velocity,
temperature, or pH count of the stream.
0 Interior diaphragms may be punctured or loose.
0 Cleaning cycles may remove too many bags from the
circuit, leaving an inadequate number in operation.
This is most likely to occur just before planned
maintenance, when a number of bags are tied off.
0 The collecting hopper below the bags may be filled
with dust. Foreign materials (bags, hose, tools)
sometimes enter the hopper and cause blockage.
0 Bag cleaning may be neglected in manual operation,
or the rapping or shaking mechanisms may suffer
mechanical failure; reverse air jet (pneumatic)
systems or timing devices may fail or become
plugged.
0 Bypassing devices may become damaged, partially or
completely blocked, or out of cycle.
Systems for collection of dust from various sources
throughout the plant are made up of hoods and enclosures at
emission points, with ducts leading to junctures and finally
to a major duct to the collecting device, usually a bag-
house. Each of the branch lines or ducts must be properly
sized to maintain adequate flow. Air intakes or cleanouts
located at critical points are equipped with dampers (valves),
which can cause malfunction. Connection of branch lines to
larger ones must not be sharp (45°, preferably 30°) and
should enter from the top or sides, never opposing. Any
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bend in the ducting should have an inside radius of 2 times
the pipe diameter. Introduction of water into the duct
collection system is another source of potential trouble.
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7.0 EMISSION PERFORMANCE TESTS
The emission performance tests are intended to ser^e as
a basis for determining compliance status of the plant
during later inspections. These initial performance tests,
therefore, must be conducted under conditions that are
representative of plant operation. Two factors are of
paramount importance: the coal being cleaned and the
equipment loadings during the test. Analysis of the coal
processed in the test should be typical with respect to
percentage of fines and moisture content. Similarly,
equipment loadings, which usually will differ from the rated
or design capacities, should represent the maximum con-
tinuous loading in plant operation. As discussed in the
balance of this section, the inspector will work with plant
officials and the emissions testing contractor in selection
of process paramaters for the emissions test.
7.1 PRETEST PROCEDURES
Before details of the test procedure are established,
the EPA inspector should discuss the test objectives with
the persons involved. In providing background information
for plant personnel, he will enhance their understanding of test
7-1
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procedures and thus establish a framework in which coop-
erative effort is likely. These pretest discussions will
focus on three principal areas: the NSPS, the operating
parameters, and the test schedule.
NSPS Briefing
The inspector should be prepared to explain the back-
ground of the New Source Performance Standards and their
relationship to the overall EPA goals. He should give
details of the procedures used by EPA in setting the stan-
dards and explain the units in which emissions are reported,
as required by regulations. He will point out that the NSPS
specifically require monitoring of thermal dryer temperature,
water supply pressure to the venturi scrubber, and pressure
loss in the venturi constriction. Although details of plant
operation are highly variable, the inspector will find that
detailed knowledge of coal cleaning processes and of EPA
activities will enable him to answer questions effectively.
Operating Parameters
The effects of all the major process variables will
determine selection of process parameters during the emis-
sion performance tests. The selected values should repre-
sent the higher extreme of emission levels encountered in
plant operations. As mentioned earlier, the major process
variables affecting emissions are coal analysis (fines and
moisture) and feed rate.
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The percentage of fines in the feed entering a thermal
dryer or air table will directly and proportionally affect
the potential emissions through the equipment. Greater
percentages of fine coal in the feed may result in larger
amounts of particulate matter escaping through the control
device to the atmosphere. For control of emissions to the
level specified by the regulations, a higher pressure drop
would be required across the scrubber. Therefore, the
percentage of fines in the feed during a performance test
should represent the higher extremes encountered in con-
tinuous plant operation.
Moisture content of feed coal has a similar direct
effect. Notice also, however, that higher moisture content
of the feed will result in reduction of air table emissions
and fugitive dust emissions. A higher moisture content of
feed entering the thermal dryer may result in flue gases
with higher moisture, causing potential difficulty in
assessing compliance with opacity standards.
The feed load (tonnage) during the performance test
should be representative of the maximun continuous rate at
which the plant is operated in overload conditions. This
will ensure representative high loading of the process
equipment during the test.
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Test Schedule
The emission performance test schedule will be deter-
mined jointly by the inspector, the test contractor, and
plant personnel. Plant personnel should provide information
regarding the schedule and analysis of coal receipts,
scheduled maintenance, operating schedules and similar
operating factors. The inspector will discuss fully with
plant personnel and the test contractor the methods and
procedures of testing. Size of test crew will depend on the
number of sampling points and total test duration. An
experienced emission testing contractor will be able to make
that judgment, with concurrence of the inspector and plant
officials.
Local weather conditions and forecasts should be
considered as the testing time approaches. Significant
rainfall or snowfall could limit the effectiveness and
accuracy of emissions tests.
It is of utmost importance that the inspector take
proper safety measures to prevent mishaps during the plant
inspections. He should always use personal protective equip-
ment such as hard hat, safety glasses or goggles, ear plugs,
safety belts, and safety shoes during the plant visit.
Where the plant prescribes standard safety procedures for
protection of staff and visiting personnel, he should adhere
to these strictly during the inspections.
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Table 7.1 outlines major planning responsibilities of
the three groups involved in emission performance tests.
7.2 TEST MONITORING
It is important to remember that the initial emissions
tests determine the reliability of later emission compliance
inspections and tests. All persons involved in the emissions
tests should seek to ensure that the tests are conducted
fairly and the test results are valid.
The inspector plays a major role in monitoring the test
procedures and plant operating parameters during the test
period. He must ensure that the tests are carried out
according to standard procedures.
The following are key factors to be monitored con-
tinuously during the tests:
Plant feed rate.
0 Percentage of fines and moisture content of the
feed.
0 Air table feed rate and baghouse pressure.
0 Thermal dryer feed rate and exit gas temperature.
0 Durations and intervals of emissions tests.
Table 7-2 presents a detailed inspection checklist to
aid the inspector in performing his duties in a thorough and
objective manner.
At least three sets of process observations are rec-
ommended. The number of stack test observations during
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Table 7-1. EMISSION PERFORMANCE TEST RESPONSIBILITIES
Group/Person
Responsibilities
EPA Inspector
Plant Personnel
Test Contractor
Arrange pretest meeting; explain
test goals and procedures.
Review and approve test schedule
prepared by test contractor.
Check location of test points.
Select test feed analysis and feed
rate in consultation with plant
personnel and request that major
parameters be recorded.
Observe and follow normal safety pro-
cedures and those specified at the plant.
Provide information for inspector
regarding types of coals cleaned
and maximum feed rates.
Provide work area for test contrac-
tor.
Identify emission points.
Identify and prepare ports.
Provide details of stack sites and
control equipment.
Provide details of plant instru-
mentation.
Provide equipment maintenance
schedule; select test dates in
consultation with inspector and
test contractor.
Present test schedule to equipment
operators and supervisors.
Familiarize test crew with
test sites, methods, and NSPS
requirements.
Prepare test schedule; obtain
approval from inspector and plant
personnel.
7-6
-------
Table 7-2. CHECKLIST FOR PERFORMANCE TEST
GENERAL INFORMATION
Plant Name:_
Mine Name:
Plant Address:.
Contact at Plant:.
Date of Inspection:.
Inspected by:
Plant Rated Feed Capacity, ton/hr:.
Plant Feed Rate, ton/hr:
Year of Plant Commissioning/
Major Modification:
Facility Data: Cleaning Techniques
Wet
Dry
Other.
Number of Stacks:.
(continued)
7-7
-------
Table 7-2 (continued)
COAL DATA
COAL SEAM:
1
2
3
Size
Surface moisture, %
1/4x0, %
Ash, %
Strip mining, %
Continuous mining, %
Conventional mining, %
Raw coal
as received
1
2
3
,
Refuse coal
1
2
3
(continued)
7-8
-------
Table 7-2 (continued).
EQUIPMENT CHECKLIST
WEIGHING DEVICE;
n Available
Type:
D Not Available
Scale design capacity:.
Size of coal weighed:
Last date of calibration:.
Ql/4 x 0
Other.
Prescribed calibration frequency:.
Plant hourly feed rate during inspection, ton/hr
1st hour
2nd hour
r
3rd hour
4th hour
5th hour
6th hour
Average hourly feed rate, ton/hr:
Maximum hourly feed rate, ton/hr:
PRIMARY CRUSHER/CRUSHER ENCLOSURE;
Feed rate:.
Feed capacity:
Load current:_
ton/hr
ton/hr
amperes
Fugitive dust control: Q Good O Poor
Type :Q Spray Q Cyclone QFab. Filter
Opacity of Emission: %
Use EPA Method 9 for all opacity readings
(continued)
7-9
-------
Table 7-2 (continued;.
SECONDARY CRUSHER
Feed rate:.
Feed capacity:.
Load current:
Fugitive dust control:
Type:
Good
.ton/hr
.ton/hr
.amperes
Poor
Spray
Cyclone
Fab. Filter
Opacity of Emission:.
AIR TABLE
Table No.
Baghouse No.
Baghouse AP, in.
Load current, amperes
Cyclone No.
Cyclone AP, in.
Stack gas opacity, %
Gas flow rate, acfm
Particulate loading,
gr/dscf
Opacity, %
Feed rate, t/hr
1
2
3
4
(.continued)
7-10
-------
Table 7-2 (continued).
SCREENS/ENCLOSURES
Location
Feed rate, ton/hr
Moisture content, %
Product sizes
Fugitive dust controls:
Type: Spray
Cyclone
Fab. Filter
Opacity of emission, %
Screen No.
1
2
3
4
THERMAL DRYER
Type.
Dryer feed rate:.
Dryer feed size:.
Feed moisture content:.
Product moisture content:.
Fan load current:
Fan suction AP:
Drying chamber AP:.
.Btu Rating
. ton/hr
.ton/hr
.amperes
. in , vac .
.in, vac.
Flue gas temperature at dryer exit: normal_
(for last 12 hrs. of continuous maximum.
normal operation) minimum.
Last date of temperature recorder
calibration: .
Cyclone outlet temperature:.
Cyclone AP:
.in.
(continued)
7-11
-------
Table 7-2 (continued).
FLUE GAS SCRUBBER
Type:
0 Water supply pressure (for
last 12 hrs. of continuous
normal operation)
0 Pressure loss at scrubber
(for last 12 hrs. of con-
tinuous normal operation)
Last date of recorder calibration:
Prescribed frequency of calibration:.
Normal
Mavimnm
Mi n-imnm
Normal
Maximum
Minimum
in.
i n .
i n ,
i n .
in.
in.
Opacity of flue gas at stack exit, %
Particulate concentration at exit, gr/dscf:.
CONVEYOR/TRANSFER POINTS
Draw a rough sketch of facility layout indicating and num-
bering the conveyors, using the graph paper on following page,
Use same numbers to identify the conveyors in the following
table:
Location
Receiving unit
Discharge conveyor width, in.
Discharge conveyor speed, ft/min.
Rated capacity, ton/hr
Load current, amperes
Type of dust control:
spray
cyclone
fab. filter
Water press, in.
Water flow, gpm
Opacity of emission, %
1
2
3
4
Conveyor No.
(continued)
7-12
-------
Table 7-2 (continued)
FACILITY LAYOUT
(continue 7-13
-------
Table 7-2 (continued).
LOADING STATION
Type:
Truck
Railroad
Barge
Unit Train
Other
Feed capacity:
Actual feed rate:
Extent of dust control:
Fan load Current:
Good
amperes
Type of dust control:
I I Spray: Water supply pressure
I I Cyclone: Pressure drop
Fabric filter: Pressure drop.
.ton/hr
.ton/hr
Poor
.in. , flow gpm
in. , flow cfm
_in. , flow cfm
Condition of collector bags
Emission opacity %
UNLOADING STATION
Type:
Truck
Barge
Feed capacity:
Actual feed rate:
Railroad
ton/hr
ton/hr
Type of Control device:
Spray: Pressure drop
I | Cyclone: Pressure drop
I I Fabric filter: Pressure drop_
_in. , flow gpm
.in. , flow cfm
.in. , flow cfm
Condition of collector bags
Emission opacity.
(continued)
7-14
-------
7-2 (continued).
COAL STORAGE
Type:! ISilo |_JFabricated Bin
Location:
Size of coal stored:
Type of coal stored: Raw coal Washed coal
Dust control device:
I I Spray
Water supply pressure in., flow gpm
I I Cyclone
Pressure drop in. , flow cfm
II Fabric filter
Pressure drop in. , flow cfm
Fan load current amps.
Condition of collector bags
Storage design feed rate ton/hr
Actual feed rate ton/hr
(continued)
7-15
-------
GENERAL/ADMINISTRATIVE
PLANT NAME
PLANT ADDRESS
SOURCE TO BE TESTED.
PLANT CONTACT
OBSERVERS
REVIEWED TEST PROTOCOL?.
Table 7-2 (continued).
FIELD OBSERVATION CHECKLIST
REVIEWED PRETEST MEETING NOTES?.
AFFILIATION
.COMMENTS.
COMMENTS.
_DATE.
.PHONE.
REVIEWED CORRESPONDENCE?.
.COMMENTS.
TEST TEAM .COMPANY NAME
SUPERVISOR'S NAME
OTHER MEMBERS
ADDRESS.
TITLE _
PHONE
(continued)
7-16
-------
Table 7-2 (continued).
GENERAL/SAMPLING SITE
STACK/DUCT CROSS-SECTION DIMENSIONS EQUIVALENT DIAMETER.
MATERIAL OF CONSTRUCTION CORRODED? LEAKS?
INTERNAL APPEARANCE: CORRODED? CAKED PARTICULATE? THICKNESS
INSULATION? THICKNESS LINING? THICKNESS
NIPPLE? I.D. LENGTH FLUSH WITH INSIDE WALL?
STRAIGHT RUN BEFORE PORTS DIAMETERS
STRAIGHT RUN AFTER PORTS DIAMETERS
PHOTOS TAKEN? OF WHAT
DRAWING OF SAMPLING LOCATION:
MINIMUM INFORMATION ON DRAWING: STACK/DUCT DIMENSIONS, LOCATION AND
DESCRIPTION OF MAJOR DISTURBANCES AND ALL MINOR DISTURBANCES, TRANS-
MISSOMETERS, AND CROSS-SECTIONAL VIEW SHOWING DIMENSIONS AND PORT
LOCATIONS.
(continued)
7-17
-------
Table 7-2 (continued)
GENERAL/SAMPLING SYSTEM
SAMPLING METHOD (e.g., EPA 5)_
SAMPLING TRAIN SCHEMATIC DRAWING:
MODIFICATIONS TO STANDARD METHOD
PUMP TYPE: FIBERVANE WITH IN-LINE OILER CARBON VANE DIAPHRAGM
PROBE LINER MATERIAL HEATED? ENTIRE LENGTH?
TYPE "S" PITOT TUBE? OTHER
PITOT TUBE CONNECTED TO: INCLINED MANOMETER OR MAGNEHELIC GAUGE
RANGE APPROX. SCALE LENGTH DIVISIONS
METER BOX BRAND SAMPLE BOX BRAND
RECENT CALIBRATION OF ORIFICE METER-DRY METER? PITOT TUBES?
NOZZLES? THERMOMETERS OR THERMOCOUPLES? MAGNEHELIC GAUGES?
NUMBER OF SAMPLING POINTS/TRAVERSE FROM FED. REG. NUMBER TO BE USED
LENGTH OF SAMPLING TIME/POINT DESIRED TIME TO BE USED
(continued)
7-18
-------
Table 7-2 (continued).
SAMPLING (USE ONE SHEET FOR EACH RUN IF NECESSARY) RUN #_
PROBE-SAMPLE BOX MOVEMENT TECHNIQUE:
IS NOZZLE SEALED WHEN PROBE IS IN STACK WITH PUMP TURNED OFF?.
IS CARE TAKEN TO AVOID SCRAPING NIPPLE ON STACK WALL?
IS AN EFFECTIVE SEAL MADE AROUND PROBE AT PORT OPENING?.
IS PROBE SEAL MADE WITHOUT DISTURBING FLOW INSJDE STACK?.
IS PROBE MOVED TO EACH POINT AT THE PROPER TIME?
IS PROBE MARKING SYSTEM ADEQUATE TO PROPERLY LOCATE EACH POINT?.
ARE NOZZLE AND PITOT TUBE KEPT PARALLEL TO STACK WALL AT EACH POINT?.
IF PROBE IS DISCONNECTED FROM FILTER HOLDER WITH PROBE IN THE STACK
ON A NEGATIVE PRESSURE SOURCE, HOW IS PARTICULATE MATTER IN THE
PROBE PREVENTED FROM BEING SUCKED BACK INTO THE STACK?
IF FILTERS ARE CHANGED DURING A RUN, WAS ANY PARTI;CULATE LOST?
METERBOX OPERATION: ,
ARE DATA RECORDED IN A PERMANENT MANNER? ARE DATA SHEETS COMPLETE?.
AVERAGE TIME TO REACH ISOKINETIC RATE AT EACH POINT
IS NOMOGRAPH SETTING CHANGED WHEN STACK TEMPERATURE CHANGES
SIGNIFICANTLY?
ARE VELOCITY PRESSURES (Ap) READ AND RECORDED ACCURATELY?.
IS LEAK TEST PERFORMED AT COMPLETION OF RUN? cfrfi @ IN Hg.
PROBE, FILTER HOLDER, IMPINGERS SEALED ADEQUATELY AFrTj^R TEST?
GENERAL COMMENT ON SAMPLING TECHNIQUES
IF ORSAT ANALYSIS IS DONE, WAS IT: FROM STACK? r$$M INTEGRATED BAG?.
WAS BAG SYSTEM LEAK TESTED? WAS ORSAT LEAK TESTED? -CHECKED AGAINST AIR?
IF DATA SHEETS CANNOT BE COPIED, RECORD: APPROXIMATE'STACK TEMPERATURE °F
NOZZLE DIA. IN. VOLUME METERED ACF
LIST ALL Ap READINGS
(continued) 7~19
-------
Table 7-2 (continued).
TRAIN ASSEMBLY/FINAL PREPARATIONS (USE ONE SHEET PER RUN IF NECESSARY) RUN #_
FILTER HOLDER CLEAN BEFORE TEST? FILTER HOLDER ASSEMBLED CORRECTLY?
FILTER MEDIA TYPE FILTER CLEARLY IDENTIFIED? FILTER INTACT?
PROBE LINER CLEAN BEFORE TEST? NOZZLE CLEAN? NOZZLE UNDAMAGED?
IMPINGERS CLEAN BEFORE TEST? IMPINGERS CHARGED CORRECTLY?
BALL JOINTS OR SCREW JOINTS? GREASE USED? KIND OF GREASE
PITOT TUBE TIP UNDAMAGED? PITOT LINES CHECKED FOR LEAKS? PLUGGING?.
METER BOX LEVELED? PITOT MANOMETER ZEROED? ORIFICE MANOMETER ZEROED?.
PROBE MARKINGS CORRECT? PROBE HOT ALONG ENTIRE LENGTH?
FILTER COMPARTMENT HOT? TEMPERATURE INFORMATION AVAILABLE?.
IMPINGERS ICED DOWN? THERMOMETER READING PROPERLY?.
BAROMETRIC PRESSURE MEASURED? IF NOT, WHAT IS SOURCE OF DATA?.
AH@ FROM MOST RECENT CALIBRATION AH@ FROM CHECK AGAINST DRY GAS METER.
NOMOGRAPH CHECK:
IF AHp = 1.80, TM = 100° F, % \\fl = 10%, Ps/Pm = 1.00, C = (0.95)
IF C = 0.95, TS = 200° F, DN = 0.375, Ap REFERENCE = (0.118)
ALIGN Ap = 1.0 WITH AH = 10; @ Ap = 0.01, AH = (0.1)
FOR NOMOGRAPH SET-UP:
ESTIMATED METER TEMPERATURE °F ESTIMATED VALUE OF P /P
s nr
ESTIMATED MOISTURE CONTENT % HOW ESTIMATED?
C FACTOR ESTIMATED STACK TEMPERATURE °F DESIRED NOZZLE DIAMETER.
STACK THERMOMETER CHECKED AGAINST AMBIENT TEMPERATURE?.
LEAK TEST PERFORMED BEFORE START IF SAMPLING? RATE CFM G> IN. Hg.
(continued)
7-20
-------
Table 7-2 (continued).
SAMPLE RECOVERY
GENERAL ENVIRONMENT-CLEANUP AREA
WASH BOTTLES CLEAN? BRUSHES CLEAN? BRUSHES RUSTY?.
JARS CLEAN? ACETONE GRADE RESIDUE ON EVAP. SPEC.
FILTER HANDLED OK? PROBE HANDLED OK? IMPINGERS HANDLED OK?_
AFTER CLEANUP: FILTER HOLDER CLEAN? PROBE LINER CLEAN?
NOZZLE CLEAN? IMPINGERS CLEAN? BLANKS TAKEN?.
DESCRIPTION OF COLLECTED PARTICULATE
SILICA GEL ALL PINK? RUN 1 RUN 2 RUN 3
JARS ADEQUATELY LABELED? JARS SEALED TIGHTLY?.
LIQUID LEVEL MARKED ON JARS? JARS LOCKED UP?_
GENERAL COMMENTS ON ENTIRE SAMPLING PROJECT:
(continued)
7-21
-------
Table 7-2 (continued).
SAMPLE TRANSPORT PARTICULATE CHECK LIST
Samples are to be the direct responsibility of
a senior member of the source test team until the
responsibility is transferred to the laboratory
supervisor.
All liquid samples must be airtight, the liquid
level marked, then stored properly upright to prevent
spillage or breakage.
All solid samples are to be sealed and stored to
prevent the loss of samples or contamination from
the ambient sources.
All sample containers must be properly marked on
outside to avoid rough handling during transport
of the sample to the laboratory.
All sample containers locked to insure the sample
integrity during transport.
The sample log (chain of custody) is initiated
during sample recovery to insure quality assurance
from the moment of collection.
(continued)
7-22
-------
Table 7-2 (continued).
ANALYTICAL PARTICULATE CHECK LIST
Analytical balance should be calibrated with Class
S weights at the time of use.
Desiccator contains anhydrous calcium sulfate.
Filter and any loose particles from the sample
container desiccated from 24 to 96 hours to a
"constant weight" means a difference of no more
than 0.5 mg or 1 percent of total weight less tare
weight, whichever is greater, between consecutive
weighings, with no less than 6 hours of desicca-
tion time between weighings and no more than 2
minutes exposure to the laboratory atmosphere
(must be less than 50% relative humidity) during
weighing.
Record level -of liquid in containers on analytical
data sheet to determine if leakage occurred during
transport.
Blank filters desiccated to a constant weight.
Blank weight should not vary from original weight
by more than + 1.0 mg.
Liquid in sample containers remeasured by the
analyst either volumetrically to +_ 1 ml or gravi-
metrically to + 0.5 g.
Acetone-rinse samples evaporate to dryness at,
ambient temperature and pressure in a tared 250-ml
beaker. Prevent dust or objects from entering the
beaker by placing a watch glass over the beaker
during evaporation.
The dried sample was desiccated to a constant
weight and reported to the nearest 0.1 mg.
The acetone blank was analyzed simultaneously with
the acetone rinse using the same procedures.
(continued)
7-23
-------
Table 7-2 (continued).
Silica gel was weighed to the nearest 0.5 g using
a balance in the field or laboratory.
Sample beakers covered with parafilm and stored
along with used filters until report is accepted by
control agency or until such time as specified by
the agency.
WAS THE TEST TEAM SUPERVISOR GIVEN THE OPPORTUNITY TO READ OVER THIS CHECKLIST?
DID HE DO SO?
OBSERVER'S NAME TITLE
AFFILIATION SIGNATURE
7-24
-------
emission performance tests will depend on the mutual agree-
ment of the inspector, plant operators, and test contractor;
for each set of stack test data, corresponding process data
should be recorded. A separate copy of the checklist for
each set of observations will facilitate the comparison of
observations.
Note that NSPS regulations specify particulate con-
centrations only for thermal dryers and air tables; all
other equipment is governed by opacity regulations. The
values observed during the test should fall within the
limits prescribed by the regulations. If they do not, plant
officials should be notified so that they may take the
necessary corrective action. The inspector should then
schedule another test in accordance with agency policy.
7-25
-------
8.0 PERIODIC COMPLIANCE INSPECTIONS
Periodic inspections following the emissions perform-
ance tests will enable the inspector to determine the
current compliance status of the plant. The inspection
mainly involves comparison of current plant operations with
those recorded during the emissions tests. The plant
instrumentation and records constitute the major information
source for the inspector. In addition, he will use the
emissions test checklist for periodic inspection, presented
as Table 8-1.
8.1 PERFORMING THE PERIODIC INSPECTION
The periodic inspection generally involves the fol-
lowing steps:
0 Obtain schedule of plant operations during the
proposed inspection period.
0 Study all available plant data including details
of the performance tests, emission points, and
control equipment.
0 Study instrumentation data gathered in performance
tests.
0 Note unusual characteristics of the plant, and
comments made by previous inspectors.
0 Inform plant officials of the proposed inspection
and ensure that records are current and available
for inspection.
-------
Table 8-1. CHECKLIST FOR PERIODIC INSPECTION
GENERAL INFORMATION
Plant Name:.
Mine Name:
Plant Address:.
Contact at Plant:.
Date of Inspection:.
Inspected by:
Plant Rated Feed Capacity, ton/hr:.
Plant Feed Rate, ton/hr:
Year of Plant Commissioning/
Major Modification:
Facility Data: Cleaning Techniques
Number of Stacks:
(continued)
Wet
Dry
Other.
8-2
-------
Table 8-1 (continued)
COAL DATA
COAL SEAM:
1
2
3
Size
Surface moisture, %
1/4x0, %
Ash, %
Strip mining, %
Continuous mining, %
Conventional mining, %
Raw coal
as received
1
2
3
Refuse coal
1
2
3
(continued)
8-3
-------
Table 8-1 (continued).
EQUIPMENT CHECKLIST
WEIGHING DEVICE:
Q Available
Type:
D Not Available
Scale design capacity:.
Size of coal weighed:
Last date of calibration:.
Other.
Prescribed calibration frequency:.
Dl/4
Plant hourly feed rate during inspection, ton/hr
1st hour
2nd hour
3rd hour
4th hour
5th hour
6th hour
Average hourly feed rate, ton/hr:
Maximum hourly feed rate, ton/hr:
PRIMARY CRUSHER/CRUSHER ENCLOSURE:
Feed rate:.
Feed capacity:
Load current:
ton/hr
ton/hr
. amperes
Fugitive dust control: Q Good QPoor
Type:Qspray D Cyclone QFab. Filter
Opacity of Emission:3 .%
Use EPA Method 9 for all opacity readings.
(continued)
8-4
-------
Table 8-1 (continued)
SECONDARY CRUSHER
Feed rate:.
Feed capacity:.
Load current:
Fugitive dust control:
Type:
Spray
Opacity of Emission:.
Good
ton/hr
.ton/hr
.amperes
Poor
Cyclone
Fab. Filter
AIR TABLE
Table No.
Baghouse No.
Baghouse AP, in.
Load current, amperes
Cyclone No.
Cyclone AP, in.
Stack gas opacity, %
Gas flow rate, acfm
Particulate loading,
gr/dscf
Opacity, %
Feed rate, t/hr
1
2
3
4
(continued)
8-5
-------
Table 8-1 (continued).
SCREENS/ENCLOSURES
Location
Feed rate, ton/hr
Moisture content, %
Product sizes
Fugitive dust controls:
Type: Spray
Cyclone
Fab. Filter
Opacity of emission, %
Screen No.
1
2
3
4
THERMAL DRYER
Type.
Dryer feed rate:
Dryer feed size:.
Feed moisture content:
Product moisture content:
Fan load current:
Fan suction AP:
Drying chamber AP:
_Btu Rating
.ton/hr
_ton/hr
.amperes
.in, vac.
.in, vac.
Flue gas temperature at dryer exit: normal °F
(for last 12 hrs. of continuous maximum. °F
normal operation) minimum °F
Last date of temperature recorder
calibration:
Cyclone outlet temperature: °F
Cyclone AP: in.
(continued)
3-6
-------
Table 8-1 (continued).
FLUE GAS SCRUBBER
Type:
0 Water supply pressure (for
last 12 hrs. of continuous
normal operation)
0 Pressure loss at scrubber
(for last 12 hrs. of con-
tinuous normal operation)
Last date of recorder calibration:
Prescribed frequency of calibration:.
Normal in.
Maximum
Minimum
Normal
Maximum
Minimum
in.
i n .
in.
in.
in.
Opacity of flue gas at stack exit, %
Particulate concentration at exit, gr/dscf:.
CONVEYOR/TRANSFER POINTS
Draw a rough sketch of facility layout indicating and num-
bering the conveyors, using the graph paper on following page.
Use same numbers to identify the conveyors in the following
table:
Location
Receiving unit
Discharge conveyor width, in.
Discharge conveyor speed, ft/min.
Rated capacity, ton/hr
Load current, amperes
Type of dust control:
spray
cyclone
fab. filter
Water press, in.
Water flow, gpm
Opacity of emission, %
Conveyor No .
1
2
3
4
(continued)
8-7
-------
Table 8-1 (continued)
i. .
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r
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i f
i
t — . -
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r
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I
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(con
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tinue
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a) : .! !..:!, _.;. :... , \
._
8-8
-------
Table 8-1 (continued).
LOADING STATION
Type: I ] Truck LJ Railroad LJ Barge
Unit Train I I Other
Feed capacity: ton/hr
Actual feed rate: ton/hr
Extent of dust control: I I Good I I Poor
Fan load Current: amperes
Type of dust control:
I Ispray: Water supply pressure in., flow gpm
I I Cyclone: Pressure drop in., flow cfm
I Fabric filter: Pressure drop in., flow cfm
Condition of collector bags
Emission opacity %
UNLOADING STATION
Type: I I Truck I I Barge | I Railroad
Feed capacity: ton/hr
Actual feed rate: ton/hr
Type of Control device:
Spray: Pressure drop in. , flow gpm
I I Cyclone: Pressure drop in. , flow cfm
O Fabric filter: Pressure drop in., flow cfm
Condition of collector bags
Emission opacity %
(continued)
8-9
-------
Table 8-1 (continued).
COAL STORAGE
Type:
Silo
I I Fabricated Bin
Location:
Size of coal stored:
Type of coal stored:.
Dust control device:
Spray
Raw coal
Washed coal
Water supply pressure
_in. , flow
_gpm
J Cyclone
Pressure drop
Fabric filter
Pressure drop
Fan load current
in., flow.
in., flow
amps.
Condition of collector bags
Storage design feed rate ton/hr
Actual feed rate ton/hr
(continued)
cfm
cfm
8-10
-------
Table 8-1 (continued).
ADDITIONAL CHECKS DURING PERIODIC INSPECTION
RECORDS
Satisfactory Unsatisfactory
Weigh feeders
Scrubber water supply
Pressure loss at scrubber
Dryer exit gas temperature
COMMENTS ON OPERATION OF PLANT EQUIPMENT BETWEEN
THE INSPECTIONS
8-11
-------
The frequency of inspections is governed by agency
policy. A quarterly inspection is recommended unless com-
plaints dictate more frequent inspections.
Duration of the inspection will depend on the plant
layout and number of emission sources; usually, however,
each plant inspection requires 6 to 8 hours. Three sets of
observations are recommended for each inspection.
Major emphasis of the inspection is on checking fa-
cility records and observing the operation of process and
control equipment, including instrumentation. The following
procedures should be performed in the order shown whenever
possible. The suggested format enables the inspector to
tour the plant, observe the process, and monitor the in-
struments during operation.
Observations Outside the Plant
0 Note plume opacity.
0 Check whether weighing devices are properly
operating.
Observations Inside the Plant
0 Use periodic inspection checklist (Table 8-1) for
recording process parameters and control equipment
data.
0 Plant records of thermal dryer exit temperature,
water supply to the scrubber, and pressure loss in the
scrubber provide information on operations during
the period between inspections. The inspector
should be satisfied that the records are accurate
and should not hesitate to ask for further in-
formation.
8-12
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8.2 DETERMINING COMPLIANCE STATUS
Compliance status of the plant is determined chiefly by
comparing the inspection observations with those obtained
during performance tests and previous inspections. Although
such comparisons do not allow the prediction of quantitative
emission rates, they do serve to indicate any emission
upsets. Understanding the significance of each item in the
checklist allows the inspector to weigh the effects of each
item on process emissions. The relationships of checklist
items with process emissions are discussed below.
Coal Data
The coal moisture content and percentage of fine coal
(-1/4 in.) determine the loadings of the thermal dryer and
air tables. Higher percentages of fine coal in the feed
tend to increase thermal dryer emissions. Higher moisture
content also increases the thermal dryer loading. If the
feed analysis differs significantly from those recorded
earlier, further investigation should be made.
Feed Rate
In general, the feed rates during periodic inspections
should not be higher than those observed during performance
tests. An increase in feed rate increases the loading of
processing equipment. Normal feed variations up to 10
percent may not significantly affect the emissions. An
8-13
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increase in feed rates should be compensated for by
additional controls, such as higher flow rates for sprays
and higher pressure drop across the venturi. Any increase
in feed rates higher than 10 percent should be questioned.
Load Current
The preparation equipment generally includes ammeters
that indicate the load current. Load current values should
be compared with those observed during performance tests.
Overloading of equipment will be indicated by the increase
in demand of load current.
Fugitive Dust Opacity
NSPS regulations specify the opacity limits for fugi-
tive dust emissions. Opacity readings according to Method 9
should be taken to determine the fugitive dust emission
compliance.
Compliance Action
If values observed in a periodic compliance test
indicate that a citation is warranted, the inspector must
clearly state to plant officials the grounds for such a
citation. An on-site citation is justified only by clear-
cut violations, such as excessive opacity or failure of the
plant to maintain or provide required records.
8-14
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REFERENCES
1".,> Leonard, J.W. , and D.R. Mitchell (eds.). Coal Prepara-
tion. Third Edition. New York. Society of Mining
Engineers of AIME. 1968.
2. Background Information for Standards of Performance:
Coal Preparation Plants, Volume 1: Proposed Standards.
U.S. Environmental Protection Agency, Research Triangle
Park, N.C. EPA-450/2-74-021a. October 1974.
3. Casey, J. Compilation of Technical Information on the
Coal Preparation Industry. U.S. Environmental Protec-
tion Agency. Research Triangle Park, N.C. (unpublished),
4. Background Information for Standards of Performance:
Coal Preparation Plants, Volume 2: Test Data Summary.
U.S. Environmental Protection Agency. Research Triangle
Park, N.C. EPA-450/2-74-0216. October 1974.
5. Air Pollutant Emission Factors Supplement (TRW Systems
Group) for U.S. Environmental Protection Agency.
Research Triangle Park, N.C. Contract No. CPA 22-69-
119. August 1970.
6. Compilation of Air Pollution Emission Factors. Second
Edition. U.S. Environmental Protection Agency.
Research Triangle Park, N.C. AP-42. April 1973.
7. Soderberg, H.E. Environmental, Energy, and Economic
Considerations in Particulate Control. Mining Congress
Journal 24-29, December 1974.
8. Technical Guide for Review and Evaluation of Compliance
Schedules for Air Pollution Sources. PEDCo-Environmental
Specialists, Inc. for U.S. Environmental Protection
Agency. Research Triangle Park, N.C. EPA Contract No.
68-02-0607. July 1973.
8-15
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APPENDIX A
NEW SOURCE PERFORMANCE STANDARDS
COAL PREPARATION PLANTS
A-l
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2232
RULES AND REGULATIONS
[PBL 463-7]
PART 60—STANDARDS OF PERFORM-
ANCE FOR NEW STATIONARY SOURCES
Coal Preparation Plants
On October 24, 1974 (39 PR 31922).
under section 111 of the Clean Air Act,
as amended, the Environmental Protec-
tion Agency (EPA) proposed standards
of performance for new and modified
coal preparation plants. Interested par-
ties were afforded an opportunity to par-
ticipate in the rulemaking by submitting
written comments. Twenty-seven com-
ment letters were received; six from coal
companies, four from Federal agencies,
four from steel companies, four from
electric utility companies, three from
State and local agencies, three from coal
industry associations and three from
other interested parties.
Copies of the comment letters and a
supplemental volume of background in-
formation which contains a summary
of the comments with EPA's responses
are available for public inspection and
copying at the U.S. Environmental Pro-
tection Agency, Public Information Ref-
erence Unit, Room 2922, 401 M Street,
S.W., Washington, D.C. 20460. In addi-
tion, the supplemental volume of back-
ground information which contains cop-
ies of the comment summary with EPA's
responses may be obtained upon written
request from the EPA Public Informa-
tion Center (PM-215), 401 M Street
S.W.. Washington, D.C. 20460 (specify
Background Information for Standards
of Performance: Coal Preparation
Plants, Volume 3: Supplemental Infor-
mation) . The comments have been care-
fully considered, and where determined
by the Administrator to be appropriate,
changes have been made to the proposed
regulations and are incorporated in the
regulations promulgated herein.
The bases for the proposed standards
are presented in "Background Informa-
tion for Standards of Performance: Coal
Preparation Plants" (EPA 450/2-74-021a,
b). Copies of this document are available
on request from the Emission Standards
Protection Agency, Research Triangle
and EngineeringDivislon, Environmental
Park, North Carolina 27711, Attention:
Mr. Don R. Goodwin.
Summary of Regulation. The promul-
gated standards of performance regulate
participate matter emissions from coal
preparation and handling facilities proc-
essing more than 200 tons/day of bitu-
minous coal (regardless of their location)
as follows: (1) emissions from thermal
dryers may not exceed 0.070 g/dscm
(0.031 gr/dscf) and 20% opacity, (2)
emissions from pneumatic coal cleaning
equipment may not exceed 0.040 g/dscm
(0.018 gr/ dscf) and 10% opacity, and
(3) emissions from coal handling and
storage equipment (processing non-
bituminous as well as bituminous coal)
may not exceed 20% opactity.
Significant Comments and Revisions to
the Proposed Regulations. Many of the
comment letters received by EPA con-
tained multiple comments. These are
summarized as follows with discussions of
any significant differences between the
proposed and promulgated regulations.
1. Applicability.—Comments were re-
ceived noting that the proposed stand-
ards would apply to any coal handling
operation regardless of size and would
require even small tipple operations and
domestic coal distributors to comply with
the proposed standards for fugitive
emissions. In addition, underground
mining activities may have been inad-
vertently included under the proposed
standards. EPA did not intend to regu-
late either these small sources or under-
ground mining activities. Only sources
which break, crush, screen, clean, or dry
large amounts of coal were intended to be
covered. Sources which handle large
amounts of coal would include coal han-
dling operations at sources such as barge
loading facilities, power plants, coke
ovens, etc. as well as plants that pri-
marily clean and/or dry coal. EPA con-
cluded that sources not intended to be
covered by the regulation handle less
than 200 tons/day; therefore, the regu-
lation promulgated herein exempts such
sources.
Comments were received questioning
the application of the standards to
facilities processing nonbituminous coals
(including lignite). As was stated in the
preamble to the proposed regulation, it
is intended for the standards to have
broad applicability when appropriate. At
the time the regulation was proposed,
EPA considered the parameters relating
to the control of emissions from thermal
FEDERAL REGISTER, VOL. 41, NO. 10—THURSDAY, JANUARY 15, 1976
A-2
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RULES AND REGULATIONS
2233
dryers to be sufficiently similar, whether
bituminous or nonbitumlnous coal was
being dried, Since the time of proposal,
EPA has reconsidered the application of
standards to the thermal drying of non-
bituminous coal. It has concluded that
such application is not prudent in the
absence of specific data demonstrating
the similarity of the drying character-
istics and emission control character-
istics to those of bituminous coal. There
are currently very few thermal dryers or
pneumatic air cleaners processing non-
bituminous fuels. The facilities tested
by EPA to demonstrate, control equip-
ment representative of best control tech-
nology were processing bituminous coal.
Since the majority of the EPA test data
and other information used to develop
the standards are based upon bituminous
coal processing, the partlculate matter
standards for thermal dryers and pneu-
matic coal cleaning equipment have been
revised to apply only to those facilities
processing bituminous coal.
The opacity standard for control of
fugitive emissions is applicable to non-
bituminous as well as bituminous coal
since honbituminous processing facili-
ties will utilize similar equipment for
transporting, screening, storing, and
loading coal, and the control techniques
applicable for minimizing fugitive par-
ticulate matter emissions will be the
same regardless of the type of coal proc-
essed. Typically enclosures with some
type of low energy collectors are utilized.
The opacity of emissions can also be re-
duced by effectively covering or sealing
the process from the atmosphere so that
any avenues for escaping emissions are
small. By minimizing the number and
the dimensions of the openings through
which fugitive emissions can escape, the
opacity and the total mass rate of emis-
sions can be reduced independently of
the air pollution control devices. Also,
water sprays have been demonstrated to
be very effective for suppressing fugitive
emissions and can be used to control even
the most difficult fugitive emission prob-
lems. Therefore, the control of fugitive
emissions at all facilities will be required
since there are several control techniques
that can be applied regardless of the
type of coal processed.
2. Thermal dryer standard.—One com-
mentator presented data and calcula-
tions which indicated that because of the
large amount of fine particles in the coal
his company processes, compliance with
the proposed standard would require the
application of a venturl scrubber with
a pressure drop of 50 to 52 inches of water
gage. The proposed standard was based
on the application of a venturl scrubber
with a pressure drop of 25 to 35 inches.
EPA thoroughly evaluated this comment
and concluded that the commentator's
calculations and extrapolations could
have represented the actual situation.
Rather than revise the standard on the
basis of the commentator's estimates,
EPA decided to perform emission tests at
a plant which processes the coal under
question. The plant tested Is controlled
with a venturl scrubber and was operated
at a pressure drop of 29 Inches during
the emission tests. These tests showed
emissions of 0.080 to 0.134 g/dscm (0.035
to 0.058 gr/dscf). These results are
numerically greater than the ^proposed
standard; however, calculations indicate
that if the pressure drop Were increased
from 29 inches to 41 Inches, the proposed
standard would be achieved. Supplemen-
tal information regarding estimates of
emission control needed to achieve the
mass standard is contained in Section n,
Volume 3 of the supplemental back-
ground information document.
Since the cost analysis of the proposed
standard was based on a venturl scrubber
operating at 25 to 35 inches venturl pres-
sure loss, the costs of operating at higher
pressure losses were evaluated. These re-
sults indicated that the added cost of
controlling pollutants to the level of the
proposed standard Is only 14 cents per
ton of plant product even if a 50 inch
pressure loss were used, and only five
cents per ton In excess of the average
control level required by state regulations
in-the major coal producing states. In
comparison to the $18.95. per ton deliv-
ered price of U.S. coal in 1974 and even
higher prices today, a maximum five
cents per ton economic impact attribut-
able to these regulations appears almost
negligible. The total Impact of 14 cents
per ton for controlling partlculate matter
emissions can easily be passed along to
the customer since the demand for
thermal drying due to freight rate sav-
ings, the elimination of handling prob-
lems due to freezing, and the needs of
the customer's process (coke ovens must
control bulk density and power plants
must control plugging of pulverizers) will
remain unaffected by these regulations.
Therefore, the economic impact of the
standard upon thermal drying will not
be large and the inflationary impact of
the standard on the price of coal will be
insignificant (one percent or less). From
the standpoint of energy consumption,
the power requirements of the air pollu-
tion control equipment are exponentially
related to the control level such that a
level of diminishing return is reached.
Because the highest pressure loss that
has been demonstrated by operation of
a venturl scrubber on a coal dryer is
41 -inches water gage, which is also the
pressure loss estimated by a scrubber
vendor to be needed to achieve the 70
mg/dscra standard, and because energy
consumption increases dramatically at
lower control levels «70 mg/dscm), a
participate matter standard lower than
70 mg/dscm was not selected. At the 70
mg/dscm control level, the trade-off be-
tween control of emissions at the thermal
dryer versus the Increase in emissions at
the power plant supplying the energy is
favorable even though the mass quantity
of all air pollutants emitted by the power
plant (SO, NOx, and partlculate matter)
are compared only to the reduction In
thermal dryer particulate matter emis-
sions. At lower than 70 mg/dscm, this
trade-off' Is not as favorable due to the
energy requirements of venturi scrubbers
at higher pressure drops. For this source,
alternative means of air pollution control
have not been fully demonstrated. Hav-
ing considered all comments on the par-
tlculate matter regulation proposed for
thermal dryers, EPA finds no reason suf-
ficient to alter the proposed standard of
70 mg/dscm except to restrict Its ap-
plicability to thermal dryers processing
bituminous coal.
3. Location o/ thermal drying sys-
tems.—Comments were received on the
applicability of the standard for power
plants with closed thermal drying sys-
tems where the air used to dry the coal Is
also used in the combustion process. As
indicated In § 60.252(a), the standard is
concerned only with effluents which are
discharged into the atmosphere from the
drying equipment. Since the pulverized
coal transported by heated air is charged
to the steam generator in a closed system,
there is no discharge from the dryer di-
rectly to the atmosphere, therefore, these
standards for thermal dryers are not ap-
plicable. Effluents from steam generators
are regulated by standards previously
promulgated (40 CFB Part 60 subpart
D). However, these standards do apply
to all bituminous coal drying operations
that discharge effluent to the atmosphere
regardless of their physical or geograph-
ical location. In addltlona to thermal
dryers located in coal preparation plants,
usually in the vicinity of the'mlnes, dry-
ers used to preheat coal at coke ovens are
alsoregulated by these standards. These
coke oven thermal dryers used for .pre-
heating are similar in all respects, in-
cluding the air polluyon control equip-
ment, to those used in coal preparation
plants,
4. Opacity standards.—The opacity
standards for thermal dryer and pneu-
matic coal cleaners were reevaluated as
a result of revisions to Method 9 for con-
ducting opacity observations (39 FR
39872). The opacity stndards were pro-
posed prior to the revisions of Method 9
and were not based upon the concept of
averaging sets of 24 observations for six-
minute periods. As a result, the proposed
standards were developed in relation to
the peak emissions of the facility rather
than the average emissions of six-minute
periods. The opacity data collected by
EPA have been reevaluated in accordance
with the revised Method 9 procedures.
and opacity standards for thermal dry-
ers and pneumatic coal cleaners have
been adjusted to levels consistent with
these new procedures. The opacity stand-
ards for thermal dryers and pneumatic
coal cleaners have been adjusted from 30
and 20 percent to 20 and 10 percent
opacity, respectively. Since the proposed
standards were based upon peak rather
than average opacity, the revised stand-
ards are numerically lower. Each of these
levels is justified based primarily upon
six-minute averages of EPA opacity ob-
servations. These data are contained in
Section LH, Volume 3 of the supplemental
background Information document.
5. Fugitive emission monitoring.—
Several commentators identified some
difficulties with the proposed procedures
for monitoring the surface moisture of
thermally dried coal. The purpose of the
proposed requirement was to determine
the probability of fugitive emissions oc-
curing from coal handling operations
FEDERAL REGISTER, VOL. 41, NO. 10—THURSDAY, JANUARY 15,
A-3
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2234
RULES AND REGULATIONS
and to estimate their extent. The com-
mentators noted that the proposed
A.S.T.M. measurement methods are diffi-
cult and cumbersome procedures not
typically used by operating facilities.
Also, It was noted that there Is too little
uniformity of techniques within Industry
for measuring surface moisture to spe-
cify a general method. Secondly, esti-
mation of fugitive emissions from such
data may not be consistent due to differ-
ent coal characteristics. Since the opac-
ity standard promulgated herein can
readily be utilized by enforcement per-
sonnel, the moisture monitoring require-
ment Is relatively unimportant. EPA has
therefore eliminated this requirement
from the regulation:
6. Open storage piles.—The proposed
regulation applied the fugitive emission
standard to coal storage systems, which
were defined as any facility used to store
coal. It was EPA's Intention that this
definition refer to some type of structure
such as a bin, silo, etc. Several com-
mentators objected to the potential ap-
plication of the fugitive emission stand-
ard to open storage piles. Since the
fugitive emission standard was not de-
veloped for application to open storage
piles, the regulations promulgated here-
in clarifies that open storage piles of coal
are not regulated by these standards.
7. Thermal dryer monitoring equip-
ment.—A number of commentators felt
that Important variables were not being
considered for monitoring venturi scrub-
ber operation on thermal dryers. The
proposed standards required monitoring
the temperature of the gas from the
thermal dryer and monitoring the
venturi scrubber pressure loss. The
promulgated standard requires, In addi-
tion to the above parameters, monitor-
Ing of the water supply pressure to the
venturi scrubber. Direct measurement
of the -water flow rate was considered
but rejected due to potential plugging
problems as a result of solids typically
found In recycled scrubber water. Also,
the higher cost of a flow rate meter In
comparison to a simpler pressure moni-
toring device was a factor In tibe selec-
tion of a water pressure monitor for
verifying that the scrubber receives ade-
quate water for proper operation. This
revision to the regulations will Insure
monitoring of major air pollution control
device parameters subject to variation
which could go undetected and unnoticed
and could grossly affect proper opera-
tion of the control equipment. A pressure
sensor, two transmitters, and a two pen
chart recorder for monitoring scrubber
venturi pressure drop and water supply
pressure, which are commercially avail-
able, will cost approximately two to three
thousand dollars Installed for each
thermal dryer. This cost Is only one-
tenth of one percent of the total Invest-
ment cost of a 500-ton-per-hour thermal
dryer. The regulations also require moni-
toring of the thermal dryer exit tem-
perature, but no added cost will result
because this measurement system is
normally supplied with the thermal dry-
ing equipment and Is used as a control
point for the process control system.
Effective date.—In accordance with
section 111 of the Act, as amended, these
regulations prescribing standards of
performance for coal preparation plants
are effective on January 15, 1976, and
apply to thermal dryers, pneumatic coal
cleaners, coal processing and conveying
equipment, coal storage systems, and
coal transfer and loading systems, the
construction or modification of which
was commenced after October 24, 1974.
Dated: January 8, 1976.
RUSSELL E. TRAIN,
Administrator.
Part 60 of Chapter I of Title 40 of the
Code of Federal Regulations is amended
as follows:
1. The table of contents Is amended by
adding subpart Y as follows:
• • • • •
Subpart Y—Standard* of Performance for Coal
Preparation Plants
Sec.
60.260 Applicability and designation of
affected facility.
60.251 Definitions.
60.262 Standards for participate matter.
60 253 Monitoring of operations.
60.264 Test methods and procedures.
AUTHORITY: Sees. Ill and 114 of the Clean
Air Act, as-amended by sec. 4(a) of Pub. L.
91-604, 84 Stat. 1678 (42 U.S.C. 1857C-6. 1867
c-9).
2. Part 60 Is amended by adding sub-
part Y as follows:
• • • • •
Subpart Y—Standards of Performance for
Coal Preparation Plants
§ 60.250 Applicability and designation
of affected facility.
The provisions of this subpart are
applicable to any of the following af-
fected facilities In coal preparation plants
which process more than 200 tons per
day: thermal dryers, pneumatic coal-
cleaning equipment (air tables), coal
processing and conveying equipment (in-
cluding breakers and crushers), coal
storage systems, and coal transfer and
loading systems.
§ 60.251 Definitions.
As used In this subpart, all terms not
defined herein have the meaning given
them in the Act and in subpart A of this
part.
(a) "Coal preparation plant" means
any facility (excluding underground
mining operations) which prepares coal
by one or more of the following proc-
esses: breaking, crushing, screening. Wet
or dry cleaning, and thermal drying.
(b) "Bituminous coal" means solid fos-
sil fuel classified as bituminous coal by
A.S.T.M. Designation D-388-66.
(c) "Coal" means all solid fossil fuels
classified as anthracite, bituminous, sub-
bituminous, or lignite by AJ3.T.M. Des-
ignation D-388-66.
(d) "Cyclonic flow" means a splrallng
movement of exhaust gases within a duct
or stack.
(e) "Thermal dryer" means any fa-
cility In which the moisture content of
bituminous coal la reduced by contact
with a heated gas stream which Is ex-
hausted to the atmosphere.
(f) "Pneumatic coal-cleaning equip-
ment" means any facility which classifies
bituminous coal by size or separates bi-
tuminous coal from refuse by application
of air stream(s).
(g) "Coal processing and conveying
equipment" means any machinery used
to reduce the size of coal or to separate
coal from refuse, and the equipment used
to convey coal to or remove coal and
refuse from the machinery. This In-
cludes, but Is not limited to, breakers,
crushers, screens, and conveyor belts.
(h) "Coal storage system" means any
facility used to store coal except for open
storage piles.
(1) "Transfer and loading system"
means any facility used to transfer and
load coal for shipment.
§ 60.252 Standards for paniculate mat-
ter.
(a) On and after the date on which
the performance test required to be con-
ducted by § 60.8 Is completed, an owner
or operator subject to the provisions of
this subpart shall not cause to be dis-
charged Into the atmosphere from any
thermal dryer gases which:
'!) Contain particulate matter In ex-
cess of 0.070 g/dscm (0.031 gr/dscf).
'2) Exhibit 20 percent opacity or
greater.
(b) On and after the date on which the
performance test required to be con-
ducted by § 60.8 Is completed, an owner
or operator subject to the provisions of
this subpart shall not cause to be dis-
charged Into the atmosphere from any
pneumatic coal cleaning equipment,
gases which:
(1) Contain particulate matter In ex-
cess of 0.040 g/dscm (0.018 gr/dscf).
(2) Exhibit 10 percent opacity or
greater.
' (c) On and after the date on which
the performance test required to be con-
ducted by I 60.8 is completed, an owner
or operator subject to the provisions of
this subpart shall not cause to be dis-
charged mto the atmosphere from any
coal processing and conveying equip-
ment, coal storage system, or coal trans-
fer and loading system processing coal,
gases which exhibit 20 percent opacity
or greater.
§ 60.253 Monitoring of operations.
(a) The owner or operator of any ther-
mal dryer shall Install, calibrate, main-
tain, and continuously operate monitor-
Ing devices as follows:
(1) A monitoring device for the meas-
urement of the temperature of the gas
stream at the exit of the thermal dryer
on a continuous basis. The monitoring
device Is to be certified by the manu-
facturer to be accurate within -± 3 • Fahr-
enheit.
(2) For affected facilities that use ven-
turi scrubber emission control equip-
ment:
(1) A monitoring device for the con-
tinuous measurement of the pressure loss
through the venturi constriction of the
FEDERAL REGISTER, VOL. 41, NO. 10—THURSDAY, JANUARY 15, 1974
A-4
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RULES AND REGULATIONS 2295
control equipment. The monitoring de-
vice Is to be certified by the manufac-
turer to be accurate within ±1 inch
water gage.
(11) A monitoring device for the con-
tinuous measurement of the water sup-
ply pressure to the control equipment.
The monitoring device Is to be certified
by the manufacturer to be accurate with-
in ±5 percent of design water supply
pressure. The pressure sensor or tap must
be located close to the water discharge
point. The Administrator may be con-
sulted for approval of alternative loca-
tions.
(b) All monitoring devices under para-
graph (a) of this section are to be recali-
brated annually in accordance with pro-
cedures under 9 60.13(b) (3) of this part.
6 60.254 Teat method* and procedures.
(a) The reference methods in Ap-
pendix A of this part, except as provided
in § 60.8(b), are used to determine com-
pliance with the standards prescribed In
5 60.252 as follows:
(1) Method 5 for the concentration of
partlculate matter and associated mois-
ture content,
(2) Method 1 for sample and velocity
traverses.
(3) Method 2 for velocity and volu-
metric flow rate, and
(4) Method 3 for gas analysis.
4b> For Method 5. the sampling time
for each run Is at least 60 minutes and
the minimum sample volume Is 0.85 dscm
(30 dscf) except that shorter sampling
times or smaller volumes, when necessi-
tated by process variables or other fac-
tors, may be approved by the Adminis-
trator. Sampling is not to be started until
30 minutes after start-up and is to be
terminated before shutdown procedures
commence. The owner or operator of the
affected facility shall eliminate cyclonic
flow during performance tests in a man-
ner acceptable to the Administrator.
(c) The owner or operator shall con-
struct the facility so that particulate
emissions from thermal dryers or pneu-
matic coal cleaning equipment can be
accurately determined by applicable test
methods and procedures under para-
graph (a) of this section.
[FR Doc.78-1240 Filed 1-14-78:8:45 am]
FEDERAL REGISTER, VOL 41, NO. 10—THURSDAY, JANUARY IS, 1976
A-5
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APPENDIX B
STANDARD TEST METHODS
B-l
-------
Appendix A—Reference Methods8
METHOD 1 SAMPLE AND VELOCITY TRAVERSES
TOR STATIONARY SO0BCES
1. Principle and Applicability.
1.1 Principle. A sampling site and the
number of traverse points are selected to aid
In the ^extraction of a representative sample.
1.2 Applicability. This method should
be applied only when specified by the test
procedures for determining compliance with
the New Source Performance Standards. Un-
less otherwise specified, this method Is not
Intended to apply to gas streams other than
those emitted directly to the atmosphere
without further processing.
2. Procedure.
2.1 Selection of a sampling site and mini-
mum number of traverse points.
2.1.1 Select a sampling site that Is at least
eight stack or duct diameters downstream
and two diameters upstream from any flow
disturbance such as a bend, expansion, con-
traction, or visible flame. For rectangular
cross section, determine an equivalent diam-
eter from the following equation:
equivalent diameter=2f (!en8th) Wdth)\
\ length+width /
equation 1-1
2.1.2 When the above sampling site
criteria can.be met, the minimum number
of traverse points Is twelve (12).
2.1.3 Some sampling situations render the
above sampling site criteria Impractical.
When this Is the case, choose a convenient
sampling location and use Figure 1-1 to de-
termine the minimum number of traverse
points. Under no conditions should a sam-
pling point be selected within l Inch of the
stack wall. To obtain the number of traverse
points for stacks or ducts with a diameter
less than 2 feet, multiply the number of
points obtained from Figure 1-1 by 0.67.
2.1.4 To use Figure 1-1 first measure the
distance from the chosen sampling location
to the nearest upstream and downstream dis-
turbances. Determine the corresponding
number of traverse points for each distance
from Figure 1-1. Select the higher of the
two numbers of traverse points, or a greater
value, such that for circular stacks the num-
ber Is a multiple of 4, and for rectangular
stacks the number follows the criteria of
section 2.2.2.
2.2 Cross-sectional layout and location of
traverse points.
2.2.1 For circular stacks locate the tra-
verse points on at least two diameters ac-
cording to Figure 1-2 and Table 1-1. The
traverse axes shall divide the stack cross
section Into equal parts.
2.2.2 For rectangular stacks divide the
cross section Into as many equal rectangular
areas as traverse points, such that the ratio
of the length to the wldU: of the elemental
areas Is between on« and two. Locate the
traverse points at the centrold of each equal
area-according o Figure 1-3.
3. References.
Determining Dust Concentration In a Gas
Stream, ASME Performance Test Code #27,
New York, N.Y., 1957.
Devorkln, Howard, et al., Air Pollution
Source Testing Manual, Air Pollution Control
District, Los Angeles, Calif. November 1963.
Methods for Determination of Velocity,
Volume, Dust and Mist Content of Gases,
Western Precipitation Division of Joy Manu-
facturing Co., Los Angeles, Calif. Bulletin
WP-50. 1968.
Standard Method for Sampling Stacks for
Particulate Matter, In: 1971 Book of ASTM
Standards, Pan 23. Philadelphia, Pa 1971,
ASTM Designation D-292S-71.
0.5
1.0
NUMBER OF DUCT DIAMETERS UPSTREAM'
(DISTANCE A)
1.5 2.0
2.8
50
40
30
20
ID
V
A
1
I
B
J
i
'DISTURBANCE
. SAMPLINQ
" SITE
^DISTURBANCE
•FROM POINT OF ANY TYPE OF
DISTURBANCE [BEND, EXPANSION, CONTRACTION, ETC.)
10
NUMBER OF DUCTDIAMETERS DOWNSTREAM*
(DISTANCE 6}
Figure 1-1. Minimum number of traverse points.
Figure 1-2. Cross section of circular stack divided into 12 equal
areas, shoeing location of traverse points at centroid of each area.
B-2
-------
Table 1-1. Location of traverse points in circular stacks .
(Percent of stack diameter from inside wall to traverse point)'
Traverse
point
number
on a
diameter
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Number of traverse points on a diameter
2
14.6
85.4
4
6.1
25.0
75.0
93.3
6
4.4
14.7
29. 5
70.5
85.3
95.6
8
3.3
10.5
19.4
32.3
67.7
80.6
89.5
96.7
10
2.5
8.2
14.6
22.6
34.2
65.8
77.4
85.4
91.8
97.5
12
2.1
6.7
11.8
17.7
25.0
35.5
64.5
75.0
82.3
88.2.
93.3
97.9
14
1.8
5.7
9.9
14.6
20.1
26.9
36.6
63.4
73.1
79.9
85.4
90.1
94.3
98.2
16
1.6
4.9
8.5
12.5
16.9
22.0
28.3
37.5
62.5
71.7
78.0
83.1
87.5
91.5
95.1
98.4
18
1.4
4.4
7.5
10.9
14.6
18.8
23.6
29.6
33.2
61.8
70.4
76.4
81.2
85.4
89.1
92.5
95.6
93.6
20
1.3
3.9
6.7
9.7
12.9
16.5
20.4
25.0
30.6
38.8
61.2
69.4
75.0
79.6
83.5
87.1
90.3
93.3
96.1
98.7
22
1.1
3.5
6.0
8.7
11.6
14.6
1S.O
21.8
26.1
31.5
39.3
60.7
63.5
73.9
78.2
82.0
85.4
88.4
91.3
94.0
96.5
98.9
.24
1.1
.3.2
5.5
7.9
10.5
13.2
1C.1
]9.4
23.0
27.2
32.3
39.8
60.2
67.7
72.8
77.0
80.6
83.9
86.8
89.5
92.1.
94.5
96.8
98.9
0
_ _._
o
o
0
1 ,
o
, , -
o
?
o
1
0
o
o
r
o
Figure 1-3. Cross section of rectangular stack divided into 12 equal
areas, with traverse points at centrpid of each area.
B-3
-------
METHOD 2 DETERMINATION OF STACK CAS
VELOCITY AND VOLUMETRIC FLOW RATE (TYPE
8 PTTOT TUBE)
1. Principle and applicability.
1.1 Principle. Stack gas velocity Is deter-
mined from the gas density and from meas-
urement of the velocity head using a Type S
(Stauschelbe or reverse type) pitot tube.
1.3 Applicability. This method should be
applied only when specified by the test pro-
cedures for determining compliance with the
New Source Performance Standards.
2. Apparatus.
2.1 Pitot tube—Type S (Figure 2-1), or
equivalent, with a coefficient within ±5%
over the working range.
2.2 Differential pressure gauge—Inclined
manometer, or equivalent, to measure velo-
city head to within 10% of the minimum
value.
2.3 Temperature gauge—Thermocouple or
equivalent attached to the pitot tube to
measure stack temperature to within 1.5% of
the minimum absolute stack temperature.
2.4 Pressure gauge—Mercury-filled U-tube
manometer, or equivalent, to measure stack
pressure to within 0.1 in. Hg.
2.5 Barometer—To measure atmospheric
pressure to within 0.1 In. Hg.
2.6 Gas analyzer—To analyze gas composi-
tion for determining molecular weight.
2.7 Pitot tube—Standard type, to cali-
brate Type S pitot tube.
3. Procedure.
3.1 Set up the apparatus as shown In Fig-
ure 2-1. Make sure all connections are tight
and leak free. Measure the velocity head and
temperature at the traverse points specified
by Method 1.
3.2 Measure the static pressure In the
stack.
3.3 Determine the stack gas molecular
weight by gas analysis and appropriate cal-
culations as indicated in Method 3.
4. Calibration.
4.1 To calibrate the pitot tube, measure
the velocity head at some point in a flowing
gas stream with both a Type S pitot tube and
a standard type pitot tube with known co-
efficient. Calibration should be done in the
laboratory and the velocity of the flowing gas
stream should be varied over the normal
working range. It is recommended that the
calibration be repeated after use at each field
site.
4.2 Calculate the pitot tube coefficient
using equation 2-1.
5. Calculations.
Use equation 2-2 to calculate the stack gas
velocity.
Jtc.t equation 2-1
where:
CPl(.,i = Pitot tube coefficient of Type S
pitot tube.
Cp,ld = Pitot tube coefficient of standard
type pitot tube (If unknown, use
0.99).
Ap,id= Velocity head measured by stand-
ard type pitot tube.
Apmi — Velocity head measured by Type S
pitot tube.
4.3 Compare the coefficients of the Type S
pitot tube determined first with one leg and
then the other pointed downstream. Use the
pitot tube only if the two coefficients differ by
no more than 0.01.
Equation 2-2
where:
(V.).,ti. = Slack gas velocity, foot per second (f.p.s.).
aroused.
CV= Pitot tube coonident, dlmcnslonlcss.
(T.).»f . = Average absolute, stack gas temperature,
_ °R.
>'AP) ftT«.=Avorace velocity head of stack gas, Inches
HiO (see. Flu. 2-2).
P, = Absolute stack pas pressure,. Inches lip.
M, = Moloeular weight of stack gas (wet basis),
Ib./lb.-mole.
6. References.
Mnrk, L. S., Mcclianlcal Engineers' Hand-
book, McGraw-Hill Book Co., Inc., New York,
N.Y., 1951.
Perry, J. H., Chemical Engineers' Hand-
book, McGraw-Hill Book Co., Inc., New York,
N.Y., 1000.
Shlgeharn. R. T., W. F. Todd, and W. S.
Smith, Significance of Errors In Stack Sam-
pling Measurements. Pnprr presented at the
Annual Meeting of the Air Pollution Control
Association, St. Louis, Mo.. June 14-19. 1970.
Standard Method for Sampling Stacks for
Paniculate Matter, In: 1971 Book of ASTM
Standards, Part 23, Phllndelphla, Pa., 1971,
ASTM Designation D-2D28-71.
Vennard, J. K., Elementary Fluid Mechan-
ics. John Wiley & Sons, Inc., New York, N.Y.,
1947.
Md = Dry molecular weight of stack pas (from
Method 3).
Bwo = Proportion by volume of water vapor in
the gas stream (from Method 4).
Figure 2-2 shows a sample recording sheet
for velocity traverse data. Use the averages
In the last two columns of Figure 2-2 to de-
termine the average stack gas velocity from
Equation 2-2.
Use Equation 2-3 to calculate the stack
gas volumetric flow rate.
Q. = 3000 (1-BWO
Equation 2-3
whore:
Qi^Voliiniotrlc flow rate, dry basis, standard condi-
tions, ft.'/hr.
A = Cross-soctlo»al area of stock, ft.1
TBtd=Absolute temperature at standard conditions.
630° R.
P.id=Absolute pressure at standard conditions, 29.92
inches Ilg.
PIPE COUPLING
TUBING ADAPTER
Figure 2-1. Pitot tube-manometer assembly.
B-4
-------
PLANT
DATE
RUN NO.
STACK DIAMETER, in..
BAROMETRIC PRESSURE, in. Hg.
STATIC PRESSURE IN STACK (Pg), in. Hg.
OPERATORS
SCHEMATIC OF STACK
CROSS SECTION
Traverse point
number
Velocity head,
in. H20
Stack Temperature
AVERAGE:
Figure 2-2. Velocity traverse dala.
B-5
-------
METHOD 3 CAS ANALYSIS FOR CARBON DIOXIDE,
EXCESS AIH, AND DBT MOLECULAR WEIGHT
1. Principle and applicability.
1.1 Principle. An Integrated or grab gas
sample Is extracted from a sampling point
and analyzed for Its components using an
Orsat analyzer.
1.2 Applicability. This method should be
applied only when specified by the test pro-
cedures for determining compliance with the
New Source Performance Standards. The test
procedure will Indicate whether a grab sam-
ple or an Integrated sample Is to be used.
2. Apparatus.
2.1 Grab sample (Figure 3-1).
2.1.1 Probe—Stainless steel or Pyrex1
glass, equipped with a filter to remove partlc-
ulate matter.
2.1.2 Pump—One-way squeeze bulb, or
equivalent, to transport gas sample to
analyzer.
'Trade name.
2.2 Integrated sample (Figure 1-2).
2.2.1 Probe—Stainless steel or Pyrex»
glass, equipped with a filter to remove par-
ttculate matter.
2.2.2 Air-cooled condenser or equivalent—
To remove any excess moisture.
2.2.3 Needle valve—To adjust flow rate.
2.2.4 Pump—Leak-free, diaphragm type,
or equivalent, to pull gas.
2.2.5 Bate meter—To measure a flow
range from 0 to 0.035 cfm.
2.2.6 Flexible bag—Tedlar,1 or equivalent,
with a capacity of 2 to 3 cu. ft. Leak test the
bag in the laboratory before using.
2.2.7 Pltot tube—Type S, or equivalent,
attached to the probe so that the sampling
flow rate can be regulated proportional to
the stack gas velocity when velocity Is vary-
ing with time or a sample traverse 1*
conducted.
2.3 Analysis.
2.3.1 Orsat analyzer, or equivalent.
PROBE
FLEXIBLE TUBING
TO ANALYZER
LTER (G
FILTER (GLASS WOOL)
SQUEEZE BULB
Figure 3-1. Grab-sampling train.
RATE METEfl
VALVE
AIR-COOLED CONDENSER / PUMP
PROBE
FILTER [GLASS WOOL)
QUICK DISCONNECT
4
RIGID CONTAINED'
Figure 3-2. Integrated gas • sampling train.
3. Procedure.
3.1 Crab sampling.
3.1.1 Set up the equipment as shown In
Figure 3-1, making sure all connections aro
leak-free. Place the probe in the stack at a
sampling point and purge the sampling line.
3.1.2 Draw sample Into the analyzer.
3.2 Integrated sampling.
3.2.1 Evacuate the flexible bag. Set up the
equipment as shown in Figure 3-2 with the
bag disconnected. Place the probe In the
stack and purge the sampling line. Connect
the bag, making sure that all connections are
tight and that there are no leaks.
3.2.2 Sample at a rate proportional to the
stack velocity.
3.3 Analysis.
3.3.1 Determine the CO2, Oz, and CO con-
centrations as soon as possible. Make as many
passes as are necessary to give constant read-
ings. If more than ten passes are necessary,
replace the absorbing solution.
3.3.2 For grab sampling, repeat the sam-
pling and analysis until three consecutive
samples vary no more than 0.5 percent by
volume for each component being analyzed.
3.3.3 For Integrated sampling, repeat the
analysis of the sample until three consecu-
tive analyses vary no more than 0.2 percent
by volume for each component being
analyzed.
4. Calculations.
4.1 Carbon dioxide. Average the three con-
secutive runs and report the result to the
nearest 0.1 % COr
4.2 Excess air. Use Equation 3—1 to calcu-
late excess air, and average the runs. Report
the result to the nearest 0.1% excess air.
%EA=
(%08)-0.-r. ( % CO)
0.264 (
.5(%
equation 3-1
where:
%EA — Percent excess air.
%Oa= Percent oxygen by volume, dry basis.
%Na= Percent nitrogen by volume, dry
basis.
% CO = Percent carbon monoxide by vol-
ume, dry basis.
0.264= Ratio of oxygen to nitrogen In air
by volume.
4.3 Dry molecular weight. Use Equation
3-2 to calculate dry molecular weight and
average the runs. Report the result to the
nearest tenth.
Md=0.44(%CO2) +0.32(%O2)
+ 0.28(%NS+%CO)
equation 3-2
where :
M«=Dry molecular weight, Ib./lb-mole.
% COj=Percent carbon dioxide by volume,
dry basis.
%O.f=Percent oxygen by volume, dry
basis.
%Na=Percent nitrogen by volume, dry
basis.
0.44— Molecular weight of carbon dioxide.
divided by 100.
0.32=Molecular weight of oxygen divided
by 100.
0.28=Molecular weight of nitrogen and
CO divided by 100.
6. References.
AltshuUer, A. P.. et al.. Storage of Oases
and Vapors In Plastic Bags. Int. 3. Air &
Water Pollution, 6:75-81, 1963.
Conner, William D., and J. 8. Nader, Air
Sampling with Plastic Bags, Journal of the
American Industrial Hygiene Association.
25:291-297. May-June 1964.
Devorkln, Howard, et al., Air Pollution
Source Testing Manual. Air Pollution Con-
trol District. Los Angeles, Calif., November
1963.
B-6
-------
METHOD 5—DETERMINATION OF PARTJCVI.ATE
EMISSIONS FROM STATIONARY SOURCES
I. Principle and apiiUcnbility.
1 l Principle. Particular matter Is with-
drawn Isoklnetlcally from the source and Us
weight Is determined gravlmetrlcally after re-
moral of uncomblnetl water.
1.2 Applicability. This method Is applica-
ble for the determination of partlculale emis-
sions from stationary sources only when
specified by the test procedures for determin-
ing compliance with New Source Perform-
ance Standards.
2. Apparatus.
21 Sampling train. The design specifica-
tions of the paniculate sampling train used
by EPA (Figure 6-1) are described In APnJ-
0581. Commercial models of this train are
available.
2.1.1 Nozzle—Stainless steel (3161 with
sharp, tapered leading edge.
212 Probe—Pyrex' glara with a heating
system capable of maintaining a minimum
ps temperature of 250' F. at the exit end
during sampling to prevent condensation
from occurring. When length limitations
(greater than about 8 ft.) are encountered at
temperatures le?~s than GOO' F.. Incoloy 025 ',
or equivalent, may be used. Probes for sam-
pling gas streams at temperatures In excess
of 600* F. must have been approved by the
Administrator.
2.1.3 PltQt tube—Type S. or equivalent,
attached to probe to monitor stack gas
velocity.
2.1.4 Filter Holder—Pyrex1 glass with
beating system capable of maintaining mini-
mum temperature of 225* F.
2.1.5 Implngers/ Condenser—Four Impin-
gers connected In eerics with glass ball joint
fittings. The first, third, and fourth Impin-
gcns are of the Grecnburg-Smllh design,
modified by replacing the tip with a '/j-lnch
ID glass tube extending to one-half Inch
from the bottom of the flask. The second 1m-
plnger Is of the Greenburg-Smlth design
with the standard tip. A condenser may be
used In place of the Implngers provided that
the moisture content of the stack gas can
still he determined.
2.16 Metering system—Vacuum gauge,
leak-free pump, thermometers capable of
measuring temperature to within 5' F., dry
gas meter with 2% accuracy, and related
equipment, or equivalent, as required to
maintain an Isoklnctlc sampling rate nnd to
determine sample volume.
2.1.7 Barometer—To measure atmospheric
pressure to ±0.1 Inches Hg.
2.2 Sample recovery.
22.1 Probe brush—At least as long ns
probe.
2.2.2 Glass wash bottles—Two.
2.2.3 Gloss sample storage containers.
22.4 Graduated cylinder—250 ml.
2 3 Analysis.
2.3.1 Glass weighing dishes.
2.3.2 Desiccator.
2.3.3 Analytical balance—To measure to
±0.1 mg.
2.3.1 Trip balance—300 g. capacity, to
measure to ±0,05 g.
3 Reagents.
3.1 Sampling.
3.1.1 Filters—Glass fiber. MSA 1100 HH'.
or equivalent, numbered for Identification
and prewelghed.
3.1.2 Silica gel—Indicating type, G-IG
mesh, dried at 176' C. (350' F.) lor 2 hours.
3.1.3 Water.
3.1.4 Crushed ice.
3.2 Sample recovery.
•12.1 Acetone—Reagent grade.
3.3 Analysis.
3.3.1 Water.
PROBE
REVERSE-TYPE
PI TOT TUBE
IMPINGER TRAIN OPTIONAL. MAV BE REPLACED
BY AN EQUIVALENT CONDENSER
HEATED AREA FJLTER HOLDER / THERMOMETER CHECK
„VACUUM
LINE
PIT01 MANOMETER
ORIFICE
THERMOMETERS
IMPINGERS ICE BATH
BY-PASSVALVE
VACUUM
GAUGE
MAIN VALVE
DRY TEST METtR AIR-TIGHT
PUMP
Figure 5-1. Parliculale-sampling hain.
3.3.a Dcslcrant--Drier!te,' Indicating.
4. Procedure.
4.1 Sampling
4.1.1 After selecting the sampling .site and
tlio minimum number of sampling points',
determine the stack pressure, temperature,
moisture, and range of velocity head.
4.1.2 Preparation of collection train.
Weigh to the nearest gram approximately 200
g. of silica gel. Label a filter of proper diam-
eter, desiccate1 for at least 24 hours and
weigh to the nearest 0.5 mg. In a room where
the relative humidity Is less than 50',' . Place
100 ml. of water In each of the first two
Implngers, leave the third Implnger empty,
and place approximately 200 g. of prewelghed
silica gel In the fourth Implnger. Set up the
train without the probe as In Figure 5-1.
Leak check the sampling train at the sam-
pling silo by plugging up the Inlet to (lie (li-
ter holder and pulling a 15 in. Hg varunm. A
leakage rate not In excess of 0.02 c.f.m. at a
vacuum cf 15 In. Hg Is acceptable. Attach
the probe and adjust the heater to provide a
gas temperature o'f about 250° F. at the probe
outlet. Turn on the filter heating system.
Place crushed Ice around the Implngers. Add
more Ice during the run to keep the temper-
ature of the gases leaving the last Implnger
as low as possible and preferably at 70" F.
or less. Temperatures above 70° F. may result
In damage to the dry gas meter from cither
moisture condensation or excessive heat.
4.1.3 Participate train operation. For each
run, record the data required on the example
sheet shown In Figure 5 -2. Take readings at
each sampling point, at least every 5 minutes.
and when significant changes In stack con-
ditions necessitate additional adjustments
In flow rnte. To begin sampling, position thn
noz/l'1 at the first traverse point with the
tip pointing directly Into the gas stream.
Immediately start tho pump and adjust the
How to Isoklncilc conditions. Sample for at.
least 5 minutes at each traverse point: sam-
pling time must be the same for earn polni.
Maintain Isoklncilc sampling throughout the
sampling period. Nomographs are available
which aid In the rapid adjustment, of the
sampling rate without other compulations,
APTD 0570 details the procedure for uslii';
these nomographs. Turn off the pump at the
conclusion of each run and record the final
readings. Remove the probe and nozzle fr-ni
the slack and handle In accordance with the
sample recovery process described In section
4.2.
4.3 Sample recovery. Exercise care in mov-
ing the collection train Trom the test site to
the sample recovery area to minimize the
loss of collected sample or the gain of
extraneous partlculate matter. Set aside a
portion of the acetone used in the sample
recovery as a blank for analysis. Measure the
volume of water from the first three Im-
plngers, then discard. Place the samples in
containers as follows:
Container No. 1. Remove the filter from
its holder, place in this container, and seal.
Container No. 2. Place loose partlculate
matter and acetone washings from all
sample-exposed surfaces prior to the filter
in this container and seal. Use a razor blade,
brush, or rubber policeman to lose adhering
particles.
Container No. 3. Transfer the silica gel
from the fourth Implnger to the original con-
tainer and seal. Use a rubber policeman as
an aid In removing silica gel from the
Implnger.
4.3 Analysis. Record the data required on
the example sheet shown in Figure 5-3.
Handle each sample container as follows:
Container No. 1. Transfer the filter and
any loose partlculate matter from the sample
container to • a tared glass weighing dish,
desiccate, and dry to a constant weight. Re-
port results to the nearest 0.5 mg.
Container No. Z. Transfer the acetone
washings to a tared beaker and evaporate to
dryness at ambient temperature and pres-
sure. Desiccate and dry to a constant weight.
Report results to the nearest 0.5 mg.
Container No. 3. Weigh the spent silica gel
and report to the nearest gram.
5. Calibration.
Use methods and equipment which have
been approved by the Administrator to
calibrate the orifice meter, pltot tube, dry
gas meter, and probe heater. Recalibrate
after each test series.
a. Calculations.
0.1 Average dry gas meter temperature
and average orifice pressure drop. See data
sheet (Figure 5-2).
1 Trade name.
1 Trade name.
' Dry using Drier!te « at 70' F,± 10' F.
B-r7
-------
6.2 Dry gas volume. Correct the sample
volume measured by the dry gas meter to
standard conditions (70° F., 29.92 Inches Hg)
by using Equation 5—1.
PK + -^1\
btr + 13.6 I
-T_—y
equation 5-1
where:
d = Volume of gas sample through the
dry gas meter (standard condi-
tions), cu. It.
V,,, = Volume of gas sample through the
dry gas meter (meter condi-
tions) , cu. ft.
T.u = Absolute temperature at standard
conditions, 630° R.
T_, = Average dry gas meter temperature,
°R.
Pb,, = Barometric pressure at the orifice
meter, Inches Hg.
AH = Average pressure drop across the
orifice meter, Inches H2O.
13.6= Specific gravity of mercury.
Pi(4 = Absolute pressure at standard con-
ditions, 29.92 Inches Kg.
6.3 Volume of water vapor.
pH,0 RT.td Ib.
Vw"
'•M
B.O P.ui 454 gm.
equation 5-2
where :
Vw,l4= Volume of water vapor in the gas
sample (standard conditions) ,
cu. ft.
Vic = Total volume of liquid collected in
Impingers and silica gel (see Fig-
ure 6-3) , ml.
pi'3o= Density of water, 1 g./ml.
Mn2o= Molecular weight of water, 18 Ib./
Ib.-mole.
R=Ideal gas constant, 21.83 inches
Hg — cu. ft./lb.-mole-°R.
T>ld = Absolute temperature at standard
conditions, 530° R.
P,u = Absolute pressure at standard con-
ditions, 29.92 Inches Hg.
6.4 Moisture content.
equation .r>-3
wbcio:
14*0 <=l*ruportlon by volume of wator vapor In the gas
stream, dimcnsloiiless.
w»i'i=Volume of water In the gas sample (standard
conditions), cu. ft.
Vl"1id=Volume of gas sample through tbo dry gas mcler
(standardconditions), t;u. ft.
6.5 Total participate weight. Determine
the total partlculate catch from the sum of
the weights on the analysis data sheet
(Figure 5-3).
0.6 Concentration.
6.6.1 Concentration in gr./s.c.f.
PLANT
LOCATION
OPERATOR
DATE
DUN NO.
SAMPLE tOt NOj.
ME I El 101 NO.
MflERiHj
r FACTOR
TRAVERSE POINT
NUMBER
TOTAL
SAMPLINO
TIME
I.I. ti^n.
AVERAGE
STATIC
PRESSURE
|PSI. ta. H».
STAC!
TEMPERATURE
ITSI. «f
AWIENT T"j»r«>iiitf
IAROUETIIC PRESSURE _____
VELOCITY
HEAD
I«PSI.
PRESSURE
DIFFERENTIAL.
ACROSS
ORIFICE
HE1M
lAHI.
In. II20
CAS SAMPU
VOLUME
IVml. II1
rnOBE LENGTH, —
NomE OIAMETH. t».____
FUME HUTER "'"""
CAS SAMPLE TEMPERATURE
AT DRY GASMETtR
INLET
"" in.1' *'
Avq.
OUTLET
<"" .„!.•'
A.8.
AVQ.
SAMPLE Ml
TEMPERATURE.
TEWEMTIM
OF CAS
IEAVIK
COHOEITSEROR
LAST KPPCER
•f
6.6.3 Concentration In Ib./cu. ft.
where:
c,=Conccntration of partleulatc matter In slack
gas, Ib./s.c.f., dry basis.
«3,600=Mg/lb.
6.7 Isoktnetlc variation.
^».td equation 5-5
Mr = Tola1 amount of partlculate matter collected,
ing.
V,rMi)-Volume of gas sample through dry gas meter
(standard conditions), cu. ft.
•t
0.00207 in. Hg-cu. ft.
«V.P.Aa
equation 5-6
I = I'd cent iif Isoklnelle sampling.
Vrp = Tolal viiluinn of liquid cullc(te(l In Implnc.'1!*
and slllra eel (Hi-e Tic. fi-3), nil.
.cii/i-I tensity of water, 1 g /ml.
11 = Heal pas ronslant, 2I.K3 Indies Hg-cu. ft./lb.
MII,M = Moh-ctjlar wi'Ipht of vater, IS Ib./lb.-molo.
\'m-\ ohmie of pas simple through thodryfas mpler
(mcf.T c^indilioiis), cu. ft.
Tm = Absolute aviiace rlry gas meter tninriiTalurn
(see KlglllrC 'J1. 'II.
I'l..i llrirnmelric pri'SSiire at Slnipllllg file, Indies
All -- A vi-icce pii't-^ine (hop across the orlllco (S(>o
Kli.-. 5 J). Indies Mill.
T. — Alisulnlr uvcinc'j stack gas terniieraluro (see
He. B 2),°K.
fl--Tnl:il samplinj! time. inln.
\',-SI:ick gas velocity calculated by Method 2,
K<|iiiilion 2 '>, ft free.
J'.' Absolute stuck gas pressure. Inches lip.
An-=CYoss-sccllonal uiea of nozr.le. sq. ft.
fi.8 Acceptable results. The following
rnnpc sets the limit on acceptable Isoklnetlc
sampling results:
If 90% < I < 1107c. the results are acceptahle.
otherwise, reject the results and repeat
the lost.
7. Krfrrrncr..
Addendum to Speciflcntions for Incinerator
Testing nt Federal F.icllitles, PH3, NCAPC,
Dec. G. 10G7.
Martin, Robert M., Construction Details of
Isnklnotlc Source Sanipltng Equipment, Kn-
vironmcntal Protoctlon Agency, APTD-0581.
Roin. Jerome J., Maintenance, Calibration,
and Operation of Isoklnetlc Source Sam-
pling Equipment. Environmental Protection
Agency. APTD-057G.
Smith, W. S.. R. T. Shigehara, nnd W. F.
Todd, A Method of Interpreting Stack Sam-
pling Data, Paper presented at the 63d An-
nual Meeting of the Air Pollution Control
AsKOclaUcm, St. Louis. Mo., June 14^19, 1970.
Smith, W. S., et. al . Stack Gas Sampling
Improved and simplified with New Equip-
ment, APCA paper No. 67-119, 1967.
Specifications for Incinerator Testing at
Federal Facilities, PUS, NCAPC. 1967.
where.:
equation 5-4
c'. = Concrntinllon of partlculate mat lor In stack
gas gr./s.c.f.j dry basis.
M.=Tot»l amount of pnrtleulate matter collected,
r niB-
™.w=Volumo of gas sample through dry gaa mctor
(standard conditions), cu. ft.
B-8
-------
PLANT.
DATE_
RUN NO.
CONTAINER
NUMBER
1
2
TOTAL
WEIGHT OF PARTICULATE COLLECTED.
mg
FINAL WEIGHT
^xd
TARE WEIGHT
I^XH
WEIGHT GAIN
FINAL
INITIAL
LIQUID COLLECTED
TOTAL VOLUME COLLECTED
VOLUME OF LIQUID
WATER COLLECTED
IMPINGER
VOLUME.
ml
SILICA GEL
WEIGHT.
fl
g" ml
CONVERT WEIGHT OF WATER TO VOLUME BY DIVIDING TOTAL WEIGHT
INCREASE BY DENSITY OF WATER. (1 g. ml):
IN,CtREf f" g = VOLUME WATER, ml
(1 g/mll
Figure5-3. Analytical da\a.
B-9
-------
METHOD 9 VISUAL DETERMINATION OF THE
OPACITY OP EMISSIONS FROM STATIONARY
SOCBCE3 '0
Many stationary sources discharge visible
emissions Into the atmosphere; these emis-
sions are usually In the shape of a plume.
This method Involves the determination of
plume opacity by qualified observers. The
method Includes procedures for the training
and certification of observers, and procedures
to be used In tha field for determination of
plume opacity. The appearance of a plume aa
viewed by an observer depends upon a num-
ber of variables, some of which may be con-
trollable and some of which may not be
controllable In the field. Variables which can
be controlled to an extent to which they, no
longer exert a significant Influence upon
plume appearance Include: Angle of the ob-
server with respect to the plume: angle of the
observer with respect to the sun; point of
observation of attached and detached steam
plume; and angle of the observer with re-
spect to a plume emitted from a rectangular
stack with a large length to width ratio. The
method Includes specific criteria applicable
to these variables.
Other variables which may not be control-
lable In the field are luminescence and color
contrast between the plume and the back-
ground against which tbe plume is viewed.
These variables exert an Influence upon the
appearance of a plume as viewed by an ob-
server, and can affect the ability of the ob-
server to accurately assign opacity values
to the observed plume. Studies of the theory
of plume opacity and field studies have dem-
onstrated that a plume is most visible and
presents the greatest apparent opacity when
viewed against a contrasting background. It
follows from this, and la confirmed by field
trials, that the opacity of a plume, viewed
under conditions where a contrasting back-
ground la present can be assigned with the
greatest degree of accuracy. However, tbe po-
tential for a positive error Is also the greatest
when a plume Is viewed under such contrast-
Ing conditions. Under conditions presenting
a less contrasting background, the apparent
opacity of a plume la less and approaches
zero as the color and luminescence contrast
decrease toward zero. As a result, significant
negative bias and negative errors can lx>
made when a plumo Is viewed under less
contrasting conditions. A negative bias de-
creases rather than Increases the possibility
that a plant operator will be cited for a vio-
lation of opacity standards due to observer
error.
Studies have been undertaken to determine
the magnitude of positive errors which can
be made by qualified observers while read-
ing plumes under contrasting conditions and
using the procedures set forth In this
method. The results of these studies (field
trials) which Involve a total of 769 sets of
26 readings each are as follows:
(I) For black plumes (133 sets at a smoke
generator), 100 percent of tbe seta were
read with a positive error' of less than 7.6
percent opacity; 99 percent were read with
a positive error of less than 5 percent opacity.
(2) For white plumes (170 sets at a smoke
generator, 168 sets at a coal-fired power plant,
298 seta at a sulfurlc acid plant), 99 percent
of the sets were read with a positive error of
less than 7.5 percent opacity; 95 percent were
read with a positive error oness than 6 per-
cent opacity.
The positive observational error a&ro--l!>.ted
with an average of twenty-five readings Is
therefore established. The accuracy of- the
method must be taken into account-when
determining possible violations of appli-
cable opacity standards.
'For a set, positive error=average opacity
determined by observers' 26 observations—
average opacity determined from transmls-
oometer's 25 recordings.
1. Principle and applicability.
I.I Principle. The opacity of emissions
from stationary sources la determined vis-
ually by a qualified observer. -
1.2 Applicability. This method Is appli-
cable for the determination of the opacity
of emissions from stationary sources pur-
suant to i 60.11 (b) and for qualifying ob-
servers for visually determining opacity of
emissions.
2. Procedures. The observer qualified In
accordance with paragraph 3 of this method
shall use the following procedures for vis-
ually determining the opacity of emissions:
2.1 Positioner The qualified observer shall
stand at a distance sufficient to provide a
clear view of the emissions with the sun
oriented in the 140* sector to his back. Con-
sistent with maintaining the above require-
ment, the observer shall, as much as possible,
make his observations from a position such
that his line of vision Is approximately
perpendicular to the plume direction, and
when observing opacity of emissions from
rectangular outlets (e.g. roof monitors, open
bughouses, nonclrcular stacks), approxi-
mately perpendicular to the longer axis of
the outlet. The observer's line of sight should
not Include more than one plume at a time
when multiple stacks are Involved, and In
any case the observer should make his ob-
servations with bis line of sight perpendicu-
lar to the longer axis of such a set of multi-
ple stacks (e.g. stub stacks on baghouses).
22 Field records. The observer shall re-
cord tbe name of the plant, emission loca-
tion, type facility, observer's .name and
affiliation, and the date on a field date sheet
(Figure 9-1). The time, estimated distance
to the emission location, approximate wind
direction, estimated wind speed, description
of the sky condition (presence and color of
clouds), and plume background are recorded
on a field data sheet at the time opacity read-
ings are Initiated and completed.
2.3 Observations. Opacity observations
shall be made at tbe point of greatest opacity
in that portion of the plume where con-
densed water vapor Is not present. The ob-
server shaU not look continuously at the
plume, but Instead sthall observe tho plume
momentarily at 15-ncond Intervals.
2.3.1 Attached steam plumes. When con-
densed water vapor Is present within the
plume as it emerges from the emission out-
let, opacity observations ehall bo made be*
yond the point in the plume at which con-
densed water vapor Ix no longer visible. The
observer shall record the approximate dis-
tance from the emission outlet to the point
In the plume at which the observations are
made.
2.33 Detached steam plume. When water
vapor In the plume condenses and becomes
visible at a distinct distance from the emis-
sion outlet, the opacity of emissions should
be evaluated at the emission outlet prior to
the condensation of water vapor and tbe for-
mation of the steam plume.
2.4 Recording observations. Opacity ob-
servations shall be recorded to the nearest 5
percent at 15-second Intervals on an ob-
servational record sheet. (See Figure 9-2 for
an example.) A minimum of 24 observations
shall be recorded. Each momentary observa-
tion recorded shnll bo deemed to represent
the average opacity of emissions for a 16-
second period.
2.5 Data Reduction. Opacity shall be de-
termined as an average of 24 consecutive
observations recorded at IB-second Intervals.
Divide the observations recorded on the rec-
ord sheet Into sets of 24 consecutive obser-
vations. A set Is composed of any 24 con-
secutive observations. Sets need not be con-
secutive In time and - In no case ehall two
sets overlap. For each set of 24 observations,
calculate the average by summing tbe opacity
of the 24 observations and dividing this sum
by 24. If an applicable standard specifies an
averaging time requiring more than 24 ob-
servations, calculate the average for all ob-
servations made during the specified time
period. Record the average opacity on a record
sheet. (See Figure 9-1 for an example.)
3. Qualifications and testing.
3.1 Certification requirements. To receive
certification as a qualified observer, a can-
didate must be tested and demonstrate, the
ability to assign opacity readings In 6 percent
Increments to 26 different black plumes and
33 different white plumes, with an error
not to exceed 16 percent opacity on any one
reading and an average error not to exceed
7.5 percent opacity In each category. Candi-
dates shall be tested according to tbe pro-
cedures described In paragraph 32. Smoke
generators used pursuant to paragraph 32
Ehall be equipped with a smoke meter which
meets the requirements of paragraph 3.3.
The certification shall be valid for a period
of 6 months, at which time the qualification
procedure must be repeated by any observer
In order to retain certification. _ '
' 3.2 Certification procedure. The certifica-
tion test consists of showing tbe candidate a
complete run of 60 plumes—26 black plumes
and 26 white plumes—generated by a smoke
generator. Plumes within each set of 26 black,
and 25 white runs shall be presented In ran-
dom order. The candidate assigns an opacity
value to each plume and records his obser-
vation on a suitable form. At the completion
of each run of 60 readings, tbe score of the
candidate Is determined. If a candidate falls
to qualify, tbe complete run of 50 readings
must be repeated in any retest. The smoke
test may be administered as part of a smoke
school or training program, and may be pre-
ceded by training or familiarization runs of
the smoke generator during which candidates
are shown black and white plumes of known
opacity.
3.3 Smoke generator specifications. Any
smoke generator used for the purposes of
paragraph 32 shall be equipped with u smoke
meter Installed to measure opacity across
the diameter of the smoke generator stock.
The- smoke meter output shall display in-
stack opacity based upon a pathlength equal
to the atack exit diameter, on a full 0 to 100
percent chart recorder scale. The smoke
meter optical design and performance shall
meet the specifications shown In Table 9-1.
The smoke meter shall be calibrated as pre-
scribed In paragraph 3.3.1 prior to the con-
duct of each smoke reading test. At tho
completion of each test, the zero and span
drift shall be checked and If the drift ex-
ceeds ±1 percent opacity, the condition shall
be corrected prior to conducting any subse-
quent test runs. The smoke meter shall bo
demonstrated, at the time of Installation, to
meet the specifications listed In Table 9-1.
This demonstration shall bo repeated fol-
lowing any subsequent repair or replacement
of the photocell or associated electronic cir-
cuitry Including the chart recorder or output
meter, or every 8 months, whichever occurs
first.
3.3.1 Calibration. Tbe emoke meter la
calibrated after allowing a minimum of 80
minutes warmup by alternately producing
simulated opacity of 0 percent and 100 per-
cent. When stable response at 0 percent or
100 percent Is noted, the smoke meter Is ad-
justed to produce an output of 0 percent or
100 percent, aa appropriate. This calibration
shall be repeated until stable 0 percent and
100 percent readings tire produced without
adjustment. Simulated 0 percent and 100
percent opacity values may be produced by
alternately switching the power to the light
source on and off while the smoke generator
Is not producing smoke.
B-10
-------
TABU •—1—61IOKE METER DESIGN AND
BPBCTFI CATIONS
Specification
Incandescent lamp
operated at nominal
rated voltage.
Photoplc (daylight
spectral response of
the human eye-
reference 4.3).
15*' moTlmnm total
angle.
15* maximum total
angle.
opacity, maxi-
mum.
Parameter:
•- Light source.
b. Spectral response
of photocell.
o. Angle of Tiew
d. Angle of projec-
tion.
e. Calibration error.
1. Zero and spaa
drift.
g. Response time—
±3% opacity.
minutes.
SB seconds.
30
3.3.2 Smoke meter evaluation. The smoke
meter design and performance are to be
evaluated as follows:
3.3.2.1 Light source. Verify from manu-
facturer's data and from voltage measure-
ments made at the lamp, as Installed, that
the lamp is operated within :tS percent of
the nominal rated voltage.
8.3.2.2 Spectral response of photocell.
Verify from manufacturer's data that the
photocell has a photoplc response; l.e, the
spectral sensitivity of the cell shall closely
approximate the standard spectral-luminos-
ity curve for photoplc vision which Is refer-
enced In (b) of Table 0-1.
3.3.2.3 Angle of view, check construction
geometry to ensure that the total angle of
view of the smoke plume, as seen by the
photocell, does not exceed 15*. The total
angle of view may be calculated from: I=2
tan-* d/2L. where »=total angle of view;
d=the sum of the photocell dlameter-f-the
diameter of the limiting aperture; and
L=tbe distance from the photocell to the
limiting aperture. The limiting aperture is
the point In the path between the photocell
and the smoke plume where the angle of
view Is most restricted. In smoke generator
•moke meters tills is normally -an orlnca
plate.
3.3.9.4 Angle of projection. Check con-
struction geometry to ensure that the total
angle of projection of the lamp on the
smoke plume does not exceed 16*. The total
angle of projection may be calculated from:
6=3 tan-» d/2L. where 1= total angle of pro-
jection: d= the sum of the length of the
lamp filament 4- the diameter of the limiting
aperture; and L= the distance from the lamp
to the limiting aperture.
3.3.2.6 Calibration error. Using neutral -
density filters of known opacity, check the
error between the actual response and the
theoretical linear response of the smoke
meter. This check is accomplished by first
calibrating the smoke meter according to
3.3.1 and then Inserting a series of three
neutral-density filters of nominal opacity of
20, 60, and 76 percent in the smoke meter
pathlength. Filters callbarted within ±2 per-
cent shall be used. Care should be taken
when inserting the Alters to prevent stray
light from affecting the meter. Make a total
of five nonconsecutlve readings for each
filter. The maximum' error on any one read-
Ing shall be 3 percent opacity.
3.3.2.6 Zero and span drift. Determine
the zero and span drift by calibrating and
operating the smoke generator in a normal
manner over a 1-hour period. The drift is
measured by checking the zero and span at
the end of this period.
3.3.2.7 Response time. Determine the re-
sponse time by producng the series of five
simulated 0 percent and 100 percent opacity
values and observing the time required to
reach stable response. Opacity values of 0
percent and 100 percent may be simulated
by alternately switching the power to tha
light source c>3 and on while the smoke
generator Is not operating.
4. References.
4.1 Air Pollution Control District Rules
and Regulations, Los Angeles County Air
Pollution Control District, Regulation IV,
Prohibitions, Rule 60.
42 Waisburd, Melvin X., Field Operations
and Enforcement Manual for Air, TJJS. Envi-
ronmental Protection Agency, Research Tri-
angle Park. N.C., APTD-1100. August 1973.
pp. 4.1-4.38.
43 Condon, E. XT., and Odishaw, H., Band-
book of Physios, McOraw-Hill Co.. K.T, N.T,
1068, Table 3.1. p. 6-52.
B-ll
-------
FIGURE 9-1
RECORD OF VISUAL DETERMINATION OF OPACITY
PAGE of
COMPANY
LOCATION
TEST NUMBER,
DATE
TYPE FACILITY..
CONTROL DEVICE
HOURS OF OBSERVATION.
OBSERVER
OBSERVER CERTIFICATION DATE_
OBSERVER AFFILIATION
POINT OF EMISSIONS
HEIGHT OF DISCHARGE POINT
ta
i
CLOCK TIME
OBSERVER LOCATION
Distance to Discharge
Direction from Discharge
Height of Observation Point
BACKGROUND DESCRIPTION
HEATHER CONDITIONS
Wind Direction
Wind Speed
Ambient Temperature
SKY CONDITIONS (clear,
overcast, % clouds, etc.)
PLUME DESCRIPTION
Color
Distance Visible
OTHER INFORIIATIOH
Initial
Final
F
1
1
SUMMARY OF AVERAGE OPACITY
Set
Number
Tlmp
Start— End
Opacity • .
Sum
Average
leadings ranged from , to % opacity
'he source was/was not in compliance with .at
the time evaluation was made.
-------
FIGURE 9-2 OBSERVATION RECORD
PAGE
OF
COMPANY
LOCATION
TEST NUMBER"
DATE
OBSERVER
TYPE FACILITY
POINT OF
W
I
M
to
Hr.
Min.
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
0
Seconds
15
JO
4b
STEAM PLUME
(check If applicable)
Attached^
Detached
COMMENTS
FIGURE 9-2 C
(Cor
COMPANY
LOCATION
TEST
DATE
•Hr.
NUMBER
Min.
TO
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
Seconds
0
It.
j
30
4b
(ch
Ai
[FR Doc.74
OBSERVATION RECORD
PAGE.
.OF
OBSERVER
TYPE FACILITY ""
POINT OF EHISSI5RT
[FB Doc.74-26150 Filed ll-ll-74;8:45 Am]
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO. 2.
4. TITLE AND SUBTITLE
Inspection Manual for the Enfor
New Source Performance Standard
Preparation Plants
3. RECIPIENT'S ACCESSION-NO.
EPA 340/1-77-022
5. REPORT DATE
,. Date of Issue: August
cement of
Coal 6. PERFORMING ORGANIZATION CODE
197
7. AUTHOR(S) 8. PERFORMING ORGANIZATION REPORT NO.
Yatendra M. Shah and James R. Burke 3210-5-CC, 3270-1-FF
9. PERFORMING ORG \NIZATION NAME AND ADDRESS
PEDCo Environmental , Inc .
11499 Chester Road
Cincinnati, Ohio 45246
12. SPONSORING AGENCY NAME AND ADDRESS
U.S. Environmental Protection A
Division of Stationary Source E
Washington, D.C. 20460
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-01-3150
13. TYPE OF REPORT AND PERIOD COVERED
Final Report
gency 14. SPONSORING AGENCY CODE
nforcement
.6. SUPPLEMENTARY NOTES
DSSE Project Officer: Mark Antell
16. ABSTRACT
Standards of Performance for new and modified coal preparation
plants .were promulgated under Section 111 of the Clean Air Act
on January 15, 1976. This report presents procedures for in-
spection of coal preparation facilities toward determination
of their compliance with NSPS. It also provides background
information that will aid the inspector in understanding the
coal preparation process and the effects of operating parameters
on process emissions.
17. KEY WORDS AND DOCUMENT ANALYSIS
a. DESCRIPTORS
Air Pollution Control
Coal Preparation
Verification Inspection
Performance Tests
18. DISTRIBUTION STATEMENT
Unlimited
»U.S. GOVERNMENT PRINTING OFFICE: 1977-260-880:104
b.lDENTIFIERS/OPEN ENDED TERMS C. COSATI Field/Group
New Source Perform- 13B
ance Standards
Enforcement Emission 14D
Testing
19. SECURITY CLASS (This Report) 21. NO. OF PAGES
Unclassified 156
20. SECURITY CLASS (This page) 22. PRICE
Unclassified
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