United States
Environmental Protection
Agency
Office of Air Quality
Planning and Standards
Research Triangle Park NC 27711
EPA-450/3-80-017
March 1980
Air
Source Category
Survey: Ceramic Clay
Industry
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EPA-450/3-80-017
Source Category Survey:
Ceramic Clay Industry
Emission Standards and Engineering Division
Contract No. 68-02-3058
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air, Noise, and Radiation
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
March 1980
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This report has been reviewed by the Emission Standards and Engineering
Division, Office of Air Quality Planning and Standards, Office of Air, Noise,
and Radiation, Environmental Protection Agency, and approved for publica-
tion . Mention of company or product names does not constitute endorsement
by EPA. Copies are available free of charge to Federal employees, current
contractors and grantees, and non-profit organizations - as supplies permit
from the Library Services Office, MD-35, Environmental Protection Agency,
Research Triangle Park, NC 27711; or may be obtained, for a fee, from the
National Technical Information Service, 5285 Port Royal Road, Springfield,
VA 22161.
Publication No. EPA-450/3-80-017
ii
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TABLE OF CONTENTS
Page
LIST OF TABLES. . v
LIST OF FIGURES vi
1. SUMMARY 1-1
1.1 Industry Description 1-1
1.2 Processes 1-2
1.3 Emission Sources 1-2
1.4 National Emissions 1-3
1.5 Available Control Technology. 1-3
1.6 "Best" Control System 1-4
1.7 State Regulations 1-4
1.8 Test Methods 1-5
1.9 Results and Recommendations 1-5
2. INTRODUCTION 2-1
3. CONCLUSIONS AND RECOMMENDATIONS 3-1
3.1 Growth of Industry 3-1
3.2 Emission Sources 3-1
3.3 National Emissions 3-2
3.4 Availability of Control Technology 3-2
3.5 State Regulations 3-3
3.6 Test Methods 3-3
3.7 Recommendations ' 3-4
111
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TABLE OF CONTENTS (continued)
4. DESCRIPTIONS INDUSTRY 4-1
4.1 Source Category Profile 4-2
4.2 Production Trends 4-6
4.3 Process Description 4-9
4.4 References 4-14
5. AIR EMISSIONS DEVELOPED IN SOURCE CATEGORY 5-1
5.1 Plant and Process Emissions 5-1
5.2 Total National Emissions From the Ceramic Clay Industry. . . 5-11
5.3 Summary 5-11
5.4 References 5-14
6. EMISSION CONTROL SYSTEMS 6-1
6.1 Current Control Techniques 6-1
6.2 Alternative Control Techniques 6-2
6.3 "Best Systems" of Emission Reduction 6-3
6.4 References 6-5
7. EMISSION DATA 7-1
7.1 Availability of Data . . . 7-1
7.2 Sample Collection and Analysis 7-4
7.3 References 7-8
8. STATE EMISSION REGULATIONS . . . 8-1
8.1 Particulate Emission Regulations 8-1
8.2 Gaseous Emission Regulations 8-7
1v
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LIST OF TABLES
Number Page
4-1 1979 Employment Distribution of Plants by SIC Codes
3253, 3261, 3262, 3263, 3264 and 3269 ............... 4-3
4-2 1979 Geographical Distribution of Plants in the
Ceramic Clay Industry
5-1 Summary of Source Test Data on Emissions from Gas
Fired Kilns ............................ 5-4
5-2 Summary of Source Test Data on Parti cul ate Emissions
From Mixers . ........................... 5'6
5-3 Summary of Source Test Data on Parti cul ate Emissions
From Presses ........................... 5-8
5-4 Particulate Emission Factors For a Typical Ceramic
Clay Industry Plant ........................ 5-10
5-5 National Emission Rate By SIC Code ................ 5-12
7-1 Summary of NEDS Report ...................... 7-3
7-2 Summary of State Data Received .................. 7-5
7-3 Summary of Industrial Contacts .................. 7-6
8-1 Summary of Selected State Particulate Emission
Regulations ............................ 8-2
8-2 Allowable Emission Rates from the Nine Selected
States for the Example Plant ................... 8-5
8-3 Summary of Control Required by the Nine Selected
State Particulate Regulations ................... 8-8
8-4 Summary of Selected State Regulations on Gaseous
Emissions ............................. 8-9
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LIST OF FIGURES
Number Page
4-1 General Process Flow Diagram 4-10
6-1 "Best" System for Emission Reduction 6~4
v1
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1. SUMMARY
This document is a Source Category Survey Report for the ceramic
clay industry. The purpose of this study is to determine the need for
New Source Performance Standards for the ceramic clay industry in
accordance with Section 111 of the Clean Air Act.
1.1 INDUSTRY DESCRIPTION
The ceramic clay industry can be separated into six segments, each
of which manufactures a finished clay product from pre-processed raw
materials: ceramic wall and floor tile, vitreous china plumbing fixtures,
vitreous china table and kitchen articles, fine earthenware (whiteware)
table and kitchen articles, porcelain electrical supplies, and pottery
products.
There are approximately 346 plants in these six industry segments
which are distributed across 40 states and Puerto Rico. Ohio and
California together contain approximately 104 of these plants. In 1977
the value of shipments from the ceramic clay industry reached nearly
1.4 billion dollars. The porcelain electrical supplies and vitreous
china plumbing fixtures industries accounted for 51 percent of this
value.
The products from the ceramic clay industry are primarily used in
the housing and electrical industries and in dining establishments and
homes. The various segments of the ceramic clay industry studied in
this report have real annual growth projections ranging from -0.5 to
-1.0 percent over the next five years. These negative growth trends are
reportedly a result of the projected decline of house construction and
the impact of imports on the U.S. ceramics market.
1-1
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1.2 PROCESSES
The ceramic -c^y industry, as defined for this study,begins with
the receipt of pre-prepared clays, additives, and glazes. The clays and
additives are mixed, molded into greenware, and fired in kilns to form a
ceramic product. Pre-prepared glazes and pigments are mixed on site to
yield specific qualities, and are applied to the products by either
spray, dipping, or brush. The glazes are then baked onto the finished
ceramic product in a final kiln. After cooling, the products are packaged
and shipped.
1.3 EMISSION SOURCES
The principle point emission sources in the ceramic clay industry
are the storage silos, kilns, and glaze spray booths. The sources of
fugitive emissions from this industry are listed below:
materials transfer points
mixing and blending operations
storage bins
materials conveying operations
friction and isostatic presses
spray booths for applying glaze
product drying and cooling operations
Emissions from the storage silos and glaze spray booths consist
mainly of particulates. The emission of hydrocarbons from the spray
booths has been a concern in the past, however these have been eliminated
by the substitution of water based glazes for previously used solvent
based glazes. Uncontrolled particulate emissions from storage silos and
spray booths would average 1.3 Ibs/ton of product (0.65 kg/Mg). However,
the ceramic clay industry routinely controls these emissions to
0.016 Ibs/ton (0.008 kg/Mg) of product and 0.013 Ibs/ton of product
(0.007 kg/Mg), respectively.
Emissions from the kilns consist mainly of particulates. Particulate
emissions rates from kilns average approximately 1.6 Ibs/ton of product
(0.8 kg/Mg). Because the kiln emissions values are low, emission control
1-2
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equipment is not used. Two states, Texas and Ohio, have even exempted
plants from obtaining permits to operate the kilns.
Because the kilns use either natural gas or electricity for heat
and have combustion temperatures typically less than 2250 F (1232 C),
and combustion is well controlled, combustion pollutants such as S02>
NO , CO, and hydrocarbons are not present in significant quantities.
/\
The combined emission rate of these pollutants for the average kiln is
well under 30 tons per year. One noncriteria pollutant, hydrogen fluoride
(HF), can be emitted from the kilns. The emission of HF results from
the application and firing of a glaze containing calcium fluoride or
from the use of feldspars containing fluoride. These practices, however,
are declining and emissions of HF are not considered significant.
Fugitive emissions in the ceramic clay industry consist primarily
of particulates. Uncontrolled fugitive particulate emissions in the
ceramic clay industry total 36.3 Ibs/ton of product (18.2 kg/Mg).
Although some of the reported data are relatively high, uncontrolled
fugitive emissions total less than 42 tons per year for the average
plant. The ceramic clay industry, however, uses collection systems and
fabric filters to reduce these emissions to 1.06 Ibs/ton of product (0.66
kg/Mg) or 1.2 tons per year for the average size plant.
1.4 NATIONAL EMISSIONS
The total controlled national particulate emissions from the ceramic
clay industry are estimated to be 872 tons per year. This does not
include emissions from the porcelain electrical supplies industry, but
does include emissions from 285 other plants. These controlled emissions
average 3.1 tons per year per plant. Average uncontrolled particulate
emissions from each plant are only 46 tons per year.
1.5 AVAILABLE CONTROL TECHNOLOGY
The Mine Safety Health Act of 1977 requires flint suppliers to ship
by bulk or covered hopper cars. In order to unload the materials,
plants in the ceramic clay industry have installed pneumatic unloading
and conveying systems. Four of the five plants visited had pneumatic
systems and the other plant receives materials in bags. An integal part
of this system is a fabric filter on top of each storage silo to remove
suspended raw materials from the conveying air.
1-3
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The fabric filters currently in use achieve an average emission reduction
of 98.7 percent. The particulate emissions from these sources are
approximately 0.016 Ibs/ton of product (0.008 kg/Mg).
Spray booths consist of an open faced chamber into which the glaze
is sprayed. This chamber is then exhausted to the atmosphere through a
collection device. Emissions from glaze spray booths are usually controlled
with liquid cyclones or a baffle system. These remove the particulates
(liquid droplets) from the air stream and discharge them in a liquid or
slurry. Units in use have a reported removal efficiency of 98 percent.
Fugitive emissions from storage bins, dry pressing operations,
transferring and conveying of materials, and mixing operations occur
within the plant and are currently controlled by drawing them into an
area exhaust system and discharging through a fabric filter with a reported
efficiency of 97 to 99+ percent. All the plants visited had fugitive
emission control devices.
1.6 "BEST" CONTROL SYSTEM
The "best" system of emission control for the ceramic clay industry
includes a pneumatic unloading and conveying system serviced by fabric
filters with an efficiency of about 99 percent. A wet cyclone would be
employed to reduce emissions from spray booths. The collection efficiency
of this device would also be approximately 99 percent. Fugitive emissions
would be controlled by drawing them into an area exhaust system and
venting through a fabric filter with a collection efficiency of 98 percent.
All the plants contacted in the ceramic clay industry currently employ
all or some of the control devices discussed above.
1.7 STATE REGULATIONS
The most common state regulations applicable to the ceramic clay
industry are process weight particulate regulations, opacity regulations,
and combustion regulations. The kilns operate primarily on natural gas
and particulate emissions are insignificant. The kilns meet the combustion
regulations in all the states examined. A typical process weight regula-
tion limits particulate emissions to 2.0 Ibs/hr (0.9 kg/hr). Available
data indicates the storage silos, kilns, and spray booths presently used
1-4
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meet the process weight participate emissions regulations in all states
studied without applying control equipment. The states universally
applied an opacity regulation limiting visible emissions to less than 20
percent opacity. Fugitive emissions as well as point source emissions
are regulated by the opacity regulation. However, correlations between
opacity and particulate emission rate from the ceramic clay industry are
not available.
1.8 TEST METHODS
EPA reference test methods have been established for the sampling
and analysis of the considered pollutants. These include EPA Methods 1
through 5 which measure particulate emissions, Methods 12a and 13b,
which measure HF emissions, and Method 25 which measures organic emissions
1.9 RESULTS AND RECOMMENDATIONS
Total uncontrolled particulate emissions from the greatest emission
sources are 40.5 Ibs/ton of product (20.3 kg/Mg). For a plant of
average size (producing 2270 tons per year or 2059 Mg/yr) this amounts
to 46 tons per year (42 Mg/yr). With the level of control currently
used by the ceramic clay industry, these emissions are reduced to 3.1
tons per year (2.8 Mg/yr). The largest plant produces 30,000 tons per
year (27,215 Mg/yr) and would emit only 41 tons of particulates per year
(37 Mg/yr) as currently controlled.
Real growth projections for the ceramic clay industry show a
decline in production. The emission data available have shown the
potential and actual emissions from the ceramic clay industry to be
relatively small.
Based on these findings it is concluded that there would be no
significant air quality improvement from the promulgation of New Source
Performance Standards for the ceramic clay industry. Therefore, it is
recommended that no New Source Performance Standards be developed at
this time.
1-5
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2. INTRODUCTION
The purpose of this study is to assess the need for a New Source
Performance Standard (NSPS) to regulate the emissions of air pollutants
from the ceramic clay industry. The six industries included are classified
under the Standard Industrial Classification (SIC) system as: 3253,
Ceramic Wall and Floor Tile; 3261, Vitreous China Plumbing Fixtures and
China and Earthenware Fittings and Bathroom Accessories; 3262, Vitreous
China Table and Kitchen Articles; 3263, Fine Earthenware (Whiteware)
Table and Kitchen Articles; 3264, Porcelain Electrical Supplies; and
3269, Pottery Products Not Elsewhere Classified. Industry segments
specifically excluded are brick and structural clay products, and clay
refractories which are currently being investigated in other EPA studies.
Processes and operations covered in this study are unloading and
conveying of processed clay, mixing and blending of raw materials,
forming the product, glazing the ware, ware and glaze drying, firing of
the article, and cooling. Materials handling processes at the mine site
are not included in this study. These processes and operations include
mixing, washing and grinding, cleaning, screening, drying, conveying and
transporting to the plant. These processes are expected to be covered in
a separate NSPS study.
The authority for conducting this study comes from the Clean Air
Act (CAA), as amended in 1977. Section 111 of the Act stipulates that
EPA publish a list of categories of stationary sources which cause or
contribute to air pollution that may be anticipated to endanger public
health and welfare. The Act also requires EPA to promulgate New Source
Performance Standards (NSPS) for sources within these categories. This
source category survey was performed to determine if development of an
NSPS for the ceramic clay industry was justified and to identify what
processes and pollutants, if any, should be subject to regulation.
2-1
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Part of the objective of the Source Category Survey of the ceramic
clay industry is to-determine if the nation would potentially realize a
significant net benefit from an NSPS for this industry. The study
involves determining if technology better than that currently being applied
exists and whether a significant number of new sources would be affected
by the NSPS. Since an NSPS would affect only new or modified plants,
growth in the industry is an important consideration. If it is determined
that an NSPS would be beneficial, then this report would provide guidance
for development of an NSPS.
The scope of this study includes 1) an examination of the processes,
pollutants, and control equipment used in the industry; 2) an assessment
of the size, distribution, and growth of the industry; 3) the identifica-
tion of "best" available control technology; and 4) an examination of
the federal, state, and local regulations pertaining to the industry.
This information was gathered by: 1) literature search of various journals
and technical publications, including EPA documents; 2) telephone and
personal contacts with industry trade associations, industry personnel,
and Federal, State, and local officials familiar with the industry; and
3) visits to operating ceramic clay plants.
This report presents the results of the study to assess the need
for development of an NSPS for the ceramic clay industry. It also
includes recommendations based upon these results.
2-2
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3. CONCLUSIONS AND RECOMMENDATIONS
3.1 GROWTH OF INDUSTRY
The growth of the ceramic clay industry has been projected to be
negative at -0.5 to -1.0 percent annually over the next five years.
No sector of the industry is projected to have growth. Imports have had
a significant impact on the industry and their increasing share of the
American consumer market is projected to continue. In general, industry
officials do not foresee any new plant construction or expansions in the
next five years within the wall and floor tile industry as well as the
remaining industry sectors. There exists unutilized production capacity
in the industry because of past cutbacks in production. It is expected
then that no plants will be built in the next five years.
3.2 EMISSION SOURCES
3.2.1 Particulate Process Emission Sources
The sources of particulate emissions in the industry are the storage
silos, kilns and glaze spray booths. The average uncontrolled emission
factors for these processes and operations are estimated to be
1.27 Ibs/ton (0.64 kg/Mg), 1.6 Ibs/ton (0.8 kg/Mg), and 1.3 Ibs/ton
(0.65 kg/Mg) produced, respectively.
3.2.2 Fugitive Emission Sources
Fugitive emission sources in the industry include transporting and
conveying of materials, mixing, blending, dry forming, and drying and
cooling of the ware. Fugitive particulate emissions are estimated to be
36.3 Ibs/ton (18.2 kg/Mg) of product.
3.2.3 Other Emissions
The gaseous and particulate emissions from the burning of fuel are
small in this industry because natural gas is the principle if not the
only fuel used, combustion temperatures are typically less than 2250°F (1232°C),
and combustion is well controlled. The quality of the ware is an important
3-1
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consideration in the type of fuel used and fuels that burn less cleanly
are not desirable according to industry personnel.
Fluoride emissions are not considered to be significant in the
industry. There was no data obtained indicating fluoride is present in
emissions from ceramic clay kilns.
3.3 NATIONAL EMISSIONS
The net uncontrolled particulate emissions from the ceramic clay
industry including fugitive emissions are estimated to be 13,100 tons
per year (1.19 x 10 kg/yr). Of this figure, 11,700 tons per year
(1.06 x 10 kg/yr) comes from fugitive emission sources. The industry
currently reduces these emissions to 870 tons per year (7.89 x 10
kg/yr) of which 340 tons per year (3.08 x 10 kg/yr) are from fugitive
sources.
The typical state regulation would limit net national emissions
from the point sources to approximately 19,300 tons/year (1.75 x 10
This allowable point source emission level is 6200 tons/year
(5.62 x 10 kg/yr) greater than the uncontrolled emission level. Some
state regulations also require fugitive emission sources to apply limited
controls. No degree of control or levels for fugitive emissions were
stipulated by the state regulations.
3.4 AVAILABILITY OF CONTROL TECHNOLOGY
Fabric filters are currently being used to control particulate
emissions both from fugitive sources and point sources. Pneumatic
systems are used for transporting and conveying raw material, and fabric
filters are used to remove suspended materials from the air streams.
Vacuum systems with lines running to areas of fugitive emission sources
are also used to collect and convey fugitive emissions to fabric filters.
The filters reduce emissions by approximately 97 to 99+ percent. The average
discharge from the fabric filter for the industry is estimated to be
0.016 IDS/ ton of product (0.008 kg/Mg).
Liquid cyclones or baffles are being used on the glaze spray booths.
The system collects the aerosol and removes the droplets from the gas
3-2
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stream. These units reduce emissions by approximately 99 percent. The
average discharge for the industry from these units is estimated to be
0.013 Ibs/ton of product (0.0065 kg/Mg).
These operations currently have uncontrolled emission levels less
than the allowable rate of the most stringent state regulations. Industry
personnel have said that controls are used to ensure the quality of the
product and to maintain a clean working environment for the safety and
welfare of the workers. The dust or spray generated would foul the
product and equipment if not removed.
3.5 STATE REGULATIONS
All the state regulatory agencies contacted (14) have said that
they do not consider this industry to be a significant source of emissions.
As a result, little monitoring or testing has been done. The test
results available tend to corroborate their position. Additional support
comes from Texas and Ohio agencies, which have exempted these sources
from permit requirements because they consider the emissions insignificant.
In general, states do have particulate regulations on opacity, fugitive
emissions, and particulate emission from combustion and process sources.
Few state regulations on combustion particulates apply to the industry
because of the predominant use of natural gas as a fuel which is often
exempted from combustion regulations. The most stringent process
weight regulation generally would limit emissions to 2.0 Ibs/hr (0.9
kg/hr). The greatest point source in the industry, the kiln, would have
uncontrolled emissions of 0.4 Ibs/hr (.18 kg/hr), well below the most
stringent state regulation. The industry would meet the most stringent
state emission regulation without using control equipment.
No visible emissions were observed during plant visits and therefore
it is believed the industry in general would meet opacity regulations.
Fugitive emission sources are contained within the plant and are controlled.
Emissions from fugitive sources meet typical state regulations.
3.6 TEST METHODS
There are EPA test methods applicable to the ceramic clay industry.
These include EPA Methods 1 through 5 for particulates, Method 13a and
3-3
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13b for HF emissions, and Method 25 for organic emissions. None of the
data obtained during this study resulted from the use of these methods
because most states do not require the ceramic industry to monitor or
test sources of emissions.
3.7 RECOMMENDATIONS
It is recommended that no New Source Performance Standards be
developed for the ceramic clay industry. National uncontrolled emissions
from the industry are less than the allowable emissions from typical
state emission regulations. The industry is also expected to have
negative growth from -0.5 to -1.0 percent annually. There exists
unutilized production capacity in the industry and therefore construction
of new plants is unlikely. Emissions from the industry are controlled
to maintain product quality and clean working conditions. No other
controls than those already described have been demonstrated in the
industry. It is estimated that promulgation of New Source Performance
Standards for the ceramic clay industry would result in no emission
reduction benefit.
3-4
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4. DESCRIPTION OF INDUSTRY
The ceramic clay industry as defined for this study consists of
6 Standard Industrial Classification (SIC) code numbers: 3253, 3261, 3262,
3263, 3264, and 3269. Manufacturers classified under these codes start
with prepared clays and materials, and produce a finished clay product.
A description of each industrial grouping, by SIC code, is presented
below :
3253 Ceramic Wall and Floor Tile
3261 Vitreous China Plumbing Fixtures, China and Earthenware
Fittings and Bathroom Accessories
3262 Vitreous China Table and Kitchen Articles - (for use in
households and in hotels, restaurants, and other commercial
institutions for preparing, serving, or storing food or
drink).
3263 Fine Earthenware (Whiteware) Table and Kitchen Articles -
(semivitreous types of earthenware table and kitchen articles
for preparing, serving, or storing food or drink).
3264 Porcelain Electrical Supplies - (electrical insulators,
molded porcelain parts for electrical supplies)
3269 Pottery Products, Not Elsewhere Classified - (firing and
decorating white china and earthenware for the trade and
manufacturing art and ornamental pottery, industrial and
laboratory pottery, stoneware and coarse earthenware table
and kitchen articles, unglazed red earthenware florists'
articles, and other pottery products, not elsewhere classified),
4-1
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4.1 SOURCE CATEGORY PROFILE
This section provides information about the distribution, employment,
density, and capacity of plants in the subgroupings of the ceramic clay
industry. Statistics on employment, and distribution of plants were
obtained from the Department of Commerce and the Department of Labor
publications. Other data and information about these industries were
supplied by trade organizations and individuals with a specific knowledge
of the industry.
Table 4-1 presents a summary, by number of employees, of the size
of the plants in each applicable SIC code. Table 4-2 provides a breakdown
by geographical regions of the number of plants in each SIC code and
also gives the percentage of the industry that these plants represent.
4.1.1 Ceramic Wall and Floor Tile
In 1972 there were 83 facilities in the United States which produced
ceramic floor and/or wall tile. Fifty-six facilities employed 20 or
more employees. The total industry employed 8300 people and produced
308.7 million square feet of tile.4 In 1977 there were 82 facilities
operating in the industry with 50 facilities employing 20 or more employees,
The total industry employed 7800 people and produced 283.7 million
square feet of tile.
Production in 1978 totaled 283 million square feet of tile, valued
at 252 million dollars. According to figures available in 1979 there
were 64 plants operating in the industry and all employed 20 or more
people.
Ceramic wall and floor tile plants are concentrated in the Mid-
Atlantic, East North Central, and West South Central geographical regions,
as shown in Table 4-2.
4.1.2 Vitreous China Plumbing Fixtures
In 1972, 59 facilities were reported producing vitreous china
plumbing fixtures. The industry employed 9600 people and produced
20,322.6 thousand pieces.7 In 1977 there were a reported 70 facilities
in operation, employing 9200 people and produced 20,176.1 thousand
pieces.
4-2
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TABLE 4-1. 1979 EMPLOYMENT DISTRIBUTION OF PLANTS BY SIC CODES
3253, 3261, 3262, 3263, 3264 and 32692
Number of
Employees
20-49
50-99
100-249
250-499
500-999
1000-2499
TOTAL
Number of Plants In Employment Range by SIC Code
3253
tell and Floor T1le
23
6
26
6
2
1
64
3261
Plumbing Fixtures
5
5
18
14
5
0
47
3262
China Table and
Kitchen Ware
2
3
6
5
1
3
20
3263
iF1ne Earthen and
Kitchen Ware
4
1
3
3
4
0
15
3264
Porcelain
Electrical Supplies
N/A
N/A
N/A
N/A
N/A
N/A
61
3269
Other Pottery Products
60
49
22
6
2
0
139
.£»
I
CO
N/A * Not Available.
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TABLE 4-2. 1979 GEOGRAPHICAL DISTRIBUTION OF PLANTS IN THE CERAMIC CLAY INDUSTRY'
Division
Nm [nglind
( rt. KM. »!.«*. HI. CI)
Hldtflt Atlinllc
(W.NJ.PA)
(»t North Cditrtl
(W.IN.U.Ml.KI)
Vrtl North Centrtl
South Atlintlc
(M .MO.K .VA.n .NC.SC.GA.Fl)
C»l South Cintrtl
Urit South C»nlr«1
(U.IA.OV.TI)
NounUIn
(ICI.ID.ut.CO.NH.M.Ul.NY)
rtctftc
(UA.ON.CA.Al.HI)
10IAL
ToUl NurtKr
of PUnts *
11
S7
83
21
21
26
6
SI
»
SIC 12S3
PUnti
0
10
14
0
9
a
13
1
64
I Of Indultry
0
27.31
20. S
0
9.16
14.1
20.96
0.26
7. SI
100
SIC 1261
( Plants
2
11
18
1
1
3
S
0
4
47
X of Industry
2.8*
19.75
19. IS
1.04
9.8
S.84
IS. 02
0
6. SI
100.01
SIC 3262
Plintl
2
7
S
0
1
2
1
0
2
20
'- of Indultry
1.17
48. i;
13.01
0
24.31
S.61
2.71
0
3.S9
9.89
SIC 1261
Plintl
0
1
7
0
2
0
0
0
1
IS
i of Induttry
0
14.)?
59 01
0
10. S
0
0
0
16.17
100
SIC 1264
Pltntl
N,A
N/A
N/A
N/A
ft/A
N/A
N/A
N/A
61
1 of Industry
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
SIC 1269
PltnU
7
26
J9
6
8
7
S
11
119
X of Industry
2.SS
IMS
15.87
1.78
2. SI
5.05
4.44
1.87
26.91
100.16
M Not ixllibll
*0ocl not !ncluo> PorcrUln (Irctrlcil Suppllet Industry (SIC 1264).
-------
The value of shipments in 1978 was approximately 407 million dollars,
a sales increase of 17 percent over 1977 values. However, this statistic
o
does not take into account the effect of inflation.
Data available in 1979 indicate 47 facilities were in production.
The data also indicates 68 percent of all plants in this industry employ
between 100 *nd 500 people. No plant employs more than 1000 people.
The hi : jst density of facilities producing vitreous plumbing
fixtures occurs in the Mid-Atlantic and East North Central states as
shown i Table 4-2.
4.1.3 v'itreous China Food Utensils
There were 34 plants reported producing vitreous china food utensils
q
in 1972 with 20 plants employing 20 or more people. There were 5900
people employed and 10.6 million dozen pieces were produced. There were
30 plants reported in this classification in 1977. Fourteen plants
Q
employed 20 or more people. There were 7100 people employed and 10.9
million dozen pieces were produced. The value of shipments in 1977
totaled about 138 million dollars.9 In 1979 there were 20 plants in
this classification. Data available in 1979 reveals that 100 percent of
all facilities in this industry employ 20 or more people. Three plants
employ between 1000 and 2500 people.
Sixty percent of the plants in this industry are located in the
Mid-Atlantic and East North Central states, as shown in Table 4-2.
4.1.4 Fine Earthenware Food Utensils
In 1972, 18 plants were reported producing fine earthenware food
utensils. Fifteen plants employed 20 or more people. Employment
totaled 6800 people and 13.7 million dozen pieces were produced. In
1977, 24 plants were reported in production with 18 plants employing 20
or more people. Employment totaled 5200 people and 13.0 million dozen
12
pieces were produced. The value of shipments in 1977 were reported at
91 million dollars.11'12
Fifteen plants were in production 1979. Data available in 1979
indicates that the existing plants are fairly evenly distributed among
the employment ranges, as shown in Table 4-1. There are, however, no
12
plants employing more than 1000 people.
4-5
-------
Nearly 50 percent of the facilities in this industry are located in
the East North Central states.
4.1.5 Porcelain Electrical Supplies
There were a reported 83 plants producing porcelain electrical
13
supplies in 1972. Sixty-four plants employed 20 or more people.
There were 13,400 people employed and 91.8 million pieces were produced.13
In 1977, the same number of plants (83) were reported in production but
l ^
with only 53 plants employing 20 or more people. There were 10,700
people employed and 76.3 million pieces were produced. The value of
l ^
shipments amounted to 338 million dollars in 1977. The 1979 data
reports 61 plants in production. There are no other current data available
concerning this segment of the ceramic industry.
4.1.6 Pottery Products, Not Elsewhere Classified
In 1972, there were a reported 426 plants producing pottery products
with 95 plants employing 20 or more people. Employment was 9100
people. In 1977, a total of 730 plants were reported in this classifica-
15
tion, with 115 plants employing 20 or more people. Employment was
10,200 and the value of product shipments was 229 million dollars in
15
1977. All of these plants employ 20 or more people. Seventy-eight
percent of these plants employ less than 100 people. No plant employs
more than 1000 people.
The highest densities of plants in this industry occur in the Mid-
Atlantic, East North Central, and Pacific states.
4.2 PRODUCTION TRENDS
This section presents recent production trends and discusses the
factors that have influenced the growth and development of this industry.
Future growth trends in these industries will also be examined.
4.2.1 Ceramic Wall and Floor Tile
Production reached a peak of nearly 308 million square feet in 1972
and 1973, but dropped to 273 million square feet in 1974. Production
has been fluctuating since then. Domestic production of ceramic wall
and floor tile in 1978 totaled 283 million square feet, an increase of
6.8 percent from 1977 production. Furthermore, the production in this
industry sector has increased nearly 16 percent in the first half of
1979.18
4-6
-------
The domestic industry, however, does not have an exclusive market
in the United States. In 1978, imports of ceramic floor and wall tile
accounted for 47 percent of the total United States consumption of this
product. This is an increase in the share of the domestic United States
market from the 30 percent share it had in 1967.
The ceramic tile industry in America has been attempting to reduce
costs and modernize in order to become more competitive with the less
expensive imports. There has been a shift towards larger, more efficient
plants with many of the small producers either going out of business,
consolidating, or merging with other corporations. Industry pressure to
maintain tariff rates and other import deterrents have been partially
successful in providing a stable United States market share for the
domestic producers.
The ceramic wall and floor tile industry relies heavily upon the
construction market. As a result, its growth is related directly to the
housing industry and construction starts. The year 1978 was a boom year
in housing and it is expected that housing starts will decline over the
20
next five years. The real growth rate of the domestic ceramic floor
and wall tile industry is estimated, by the U.S. Department of Commerce,
20
to be a -0.8 percent annually for the next five years.
4.2.2 Vitreous Plumbing Fixtures
Domestic production of vitreous plumbing fixtures was valued at 407
million dollars in 1978, up 58.6 million dollars from 1977 values.21
This increase in product value is a result, in part, of inflation. In
1977 it was estimated that the vitreous plumbing industry would be pro-
ducing near its maximum capacity of 18,000,000 units.
The sanitaryware industry is no longer monopolized by the vitreous
plumbing fixtures industry. Plastics have made vast progress in this
area and are very competitive with the vitreous plumbing fixtures. No
quantifiable data is currently available on how much impact plastics
have made. The industry is also tied to the housing industry in much
the same way as the ceramic wall and floor tile industry. As a result
of competition from plastics and the decline of the housing market, the
real growth for the vitreous plumbing fixtures industry is projected to
23
be a -0.8 percent annually for the next five years.
4-7
-------
4.2.3 Vitreous China Food Utensils
Product shipments in the vitreous china food utensil industry were
valued at approximately 138 million dollars in 1977.24 This industry
depends mainly upon hotels, restaurants and home markets. According to one
industry official "The trend towards finger foods, such as hamburgers
25
and fried chicken, does little to enhance the hotel china business".
Personal expenditures or consumer spending, the major influence in the
china food utensils industry, is expected to decrease over the next five
years. Therefore, the real growth rate for the vitreous china food
utensil industry is estimated to be -0.5 percent annually for the next
five years.
4.2.4 Fine Earthenware Food Utensils
In 1977 product shipments from facilities in this classification
27
were valued at about 91 million dollars. The fine earthenware food
utensil industry is influenced by many of the same factors influencing
the vitreous china food utensil industry. Especially important is the
amount of personal expenditures. The real growth rate projection for
28
this industry is -1.0 percent annually for the next five years.
4.2.5 Porcelain Electrical Supplies
The value of shipments from plants producing porcelain electrical
29
supplies in 1977 was 338 million dollars. This industry is related to
housing and construction starts in the same way as are the ceramic wall
and floor tile and vitreous plumbing fixtures industries. Because of
this, the real growth forecast is the same as for those two industries;
-0.8 percent annually for the next five years.
4.2.6 Pottery Products, Not Elsewhere Classified
The shipments of products from this industry were valued at
229 million dollars in 1977. ' The production and sale of pottery
products are also related to the amount of personal expenditures.
Because of this relation the real growth projection is -1.0 percent
32
annually for the next five years.
4.2.7 Net Trends
The 5 year real growth rate projections for segments of the ceramic
33
clay industry range from -0.5 percent to -1.0 percent annually,
4-8
-------
and therefore no new plants are expected to be built in the next five
years. A common influence for all of these growth projections is the
state of the national economy. It is anticipated that the ceramic clay
industry will experience fluctuations in production due to competition
from foreign producers and other domestic products.
4.3 PROCESS DESCRIPTION
The processes used in the manufacture of the various ceramic clay
products covered in this study are very similar and therefore a singular
description will be given. The processes vary slightly in accordance
with the type of product manufactured. The variation is in the body
material mixture and the type of forming. Although the quantity of
emissions may vary, the type of emissions are generally not affected by
the product being manufactured.
As illustrated in Figure 4-1, the processes can be divided conveni-
ently into three operations; body preparation, firing and glazing.
Glazing and firing follow body preparation but glazing can occur before
or after firing.
4.3.1 Body Preparation
Body preparation consists of all process steps prior to firing or
glazing. Body preparation therefore includes the mixing of the raw
materials, in the proper proportions, to form the body material. It
also includes the forming of the greenware, or clay body, by a wet or
dry process.
Raw materials for the ceramic clay industry include processed and
prepared materials and raw ores. If raw ore is received it is crushed,
ground, screened and cleaned to prepare it for use. Prepared materials
are received in either railroad hopper cars or bags and sometimes in
bulk trucks. The hoppers are unloaded pneumatically into silos. Bags are
unloaded by hand or front-end loaders. The prepared materials are
stored in silos or enclosed bins. The raw materials, consisting of
clays (china clay, ball clay, kaolin, etc.), fluxes (feldspars, talc,
soda ash, etc.), silicas (flints, quartz, etc.) and other minor ingredients
4-9
-------
Body Preparation
Glaze Preparation
"
Raw
Material
Storage
Transferring
and
Conveying
Mixing
and
Blending
1!
4
1
) (Dry or Met)
1 (operation)
Dry Forming
Friction
Isostatl
J
Press
c Press
Finishing
,
, Wet Forming
Raw ..
HaUrial "
Storage
1
Transferring |
and |
Conveyl ng
,
Mixing i
and |
Blending '
Ram Pressing
Jigger Ing
Slip Casting
Pug Mill
j 1
Drying
Finishing
J
. .
Firing
f
Glazing
4
Glost Firing
1
' «
It Glazing
«-- Fir
n
Ing
1
1
I
11
-
Legend
(Point Source Paniculate Erlssions
'Fugitive Particulate Emissions
Gaseous Emissions
Figure 4-1. General Process Flow Diagram
4-10
-------
are blended to form the body material. The clays constitute the main
body. Fluxes are added to lower the required firing temperature and to
promote vitrification. Vitrification is the formation of glass by
partial melting during firing. Silicas are added for strength. They
undergo structural changes upon firing to bond the clay particles into a
strong, rigid mass.
Uncontrolled fugitive emissions from the unloading and storage of
materials average approximately 35 Ibs per ton (18 kg/Mg) "of product
manufactured according to AP-42 factors. Controls such as enclosing
the unloading area and conveying equipment can reduce these emissions to
approximately 8 Ibs/ton of product (4 kg/Mg). Fabric or bag filters
installed on storage silos reduce emissions from 1.27 Ibs/ton (0.6 kg/Mg)
on the upstream side of the device to less than 0.02 Ibs/ton (0.01 kg/Mg)
on the downstream side.
The raw materials are then batched and mixed to form the body
material. Water is usually added during mixing. However in the manufac-
ture of wall and floor tile and electrical supplies these are mixed dry
if dry forming is used. Uncontrolled fugitive emissions for dry mixing
and conveying average approximately 18 Ibs/ton (9 kg/Mg). With control
devices such as fabric filters these emissions can be reduced to approxi-
mately 1 lb/ton (0.5 kg/Mg).
Wet forming processes, such as ram pressing, jiggering, slipcasting,
etc., form a moist greenware product. Dry forming using friction presses
or isostatic presses form tile or electrical products. Wet forming does
not produce any emissions. Dry forming is reported to produce fugitive
emissions averaging 19 Ibs/ton (10 kg/Mg). These emissions can be
collected by a vacuum system and ducted to a fabric filter to reduce
these emissions to approximately 0.5 Ibs/ton (0.25 kg/Mg).
The greenware formed by wet forming is allowed to partially dry
before glazing or firing takes place. Very little if any emissions
occur during the drying process. Typically the drying is done in open
areas at room temperature. Tiles and electrical products formed by dry
processes are "vacuumed" and fettled. They are then glazed if necessary
and fired.
4-11
-------
4.3.2 Fi ri ng
The green body ts placed on kiln cars. The cars are then loaded
into the kiln (typically a tunnel kiln fired with natural gas). As the
body temperature is raised, carbonaceous matter is burned out, chemical
water is excluded, and carbonates and sulfates begin to decompose. On
further heating, some of the minerals break down into new forms, and the
fluxes react with the decomposing minerals to form liquid silicates or
glasses. More glass forms as the temperature is raised and begins to
pull the unmelted grains together causing shrinkage and an increase in
bulk density. When the proper degree of maturity is reached or the
proper amount of porosity is achieved the body is cooled. Upon cooling
the liquid glass becomes rigid thus forming a strong bond between the
remaining crystalline grains. Depending upon the degree of porosity
remaining in the body, it is classified as unvitrified (clay pots,
etc.), semivitrified (stoneware, dinnerware, etc.) or vitrified (white-
ware, etc.).
Firing can be accomplished in one or two stages. Typically the
body is first fired at a low temperature (bisque fired) which removes
the volatile organics and allows part or all of the shrinking to occur.
Glaze is then applied to the body which is fired (glost firing) to
maturity at a temperature between 2100 to 2300°F (1149 to 1260°C).
However, low cost items can be one-fired. In this process the green
body is glazed and then fired to maturity at a temperature of approximately
2220°F (1215°C). In fine china, the body is first fired to maturity at
a temperature usually between 2100 -2200°F (1149 to 1204°C), then glazed.
The glazed body is again fired at a low temperature, usually 1300 -
1350°F (704 to 732°C), to set the glaze.
The kilns are typically fired using natural gas. The quality of
the fuel is important in order that the product not be adversely affected.
Natural gas is a clean burning fuel generating low levels of particulate
emissions. Source testing of kiln exhausts report uncontrolled emission
of 1.6 Ibs particulates/ton (0.8 kg/Mg) of product with no significant
gaseous emissions.
4-12
-------
4.3.3 Glazing
The proportions of raw materials used to form the glaze are very
similar to body composition except the silica oxide is in higher concen-
tration. The composition includes a frit (which imparts the color of
the glaze, its opacity and other characteristics), clay and other minor
ingredients. The frit material usually comes preground in 50 Ib bags.
There are a number of types of frits commercially available. The clays
are generally received in bulk by rail car and truck. The materials are
batched and mixed with water usually in a ball mill. The glaze is then
stored ready for use. Fugitive emissions similar to those discussed for
the bulk material handling operations occur in the glaze material
conveying and transferring phases of this operation.
The glaze is applied to the body either by hand dipping or spraying.
Hand dipping generates no emissions. Spray emissions are usually controlled
by a spray booth equipped with a baffle or water curtain control device.
The booths are usually small enclosures of approximately 8 cubic feet.
The uncontrolled emissions from spray operations have been reported as
averaging 1.3 Ibs/ton (0.7 kg/Mg) of particulate while controlled emissions
are 0.013 Ibs/ton (0.007 kg/Mg). No significant gaseous emissions have
been reported. Fluoride and lead have virtually been eliminated from
the glazes because of health related problems and regulations. No VOC
emissions are present since water based glazes have replaced the organic
solvent based glazes.
Some finishing of the product may be required. Finishing might
require grinding, polishing, etc. As a result of quality control,
finishing is seldom necessary and is not considered a significant source
of emissions. Some grinding is done on electrical porcelain to form the
finished product but this is usually done with the addition of water,
therefore the emissions are not considered significant.
The product once fired to maturity is cooled to room temperature,
stored and shipped. No significant emissions occur during these operations.
4-13
-------
4.4 REFERENCES
1. Statistical Policy Division, Office of Management and Budget,
Standard Industrial Classification Manual. Washington, D.C.:
U.S. Government Printing Office, 1972. p. 138-140.
2. Economic Information Systems, Inc., EIS, Industrial Plants.
Dialog Database, Lockheed, Inc. File 22. October 31, 1979.
3. Reference 2.
4. U.S. Department of Commerce, Bureau of Census, 1977 Census of
Manufacturers. MC77-1-32B.
5. U.S. Department of Commerce, Industry and Trade Administration,
"Construction Review". 25(8): 62. 1979.
6. Reference 2.
7. U.S. Department of Commerce, Bureau of Census, Current Industrial
Reports. MQ-34E, August, 1979. p. 3.
8. Reference 2.
9. Reference 5.
10. Reference 2.
11. Reference 6.
12. Reference 2.
13. Reference 6.
14. Reference 2.
15. Reference 6.
16. Reference 2.
17. Telecon. Pierce, D.R., Radian Corporation with Jack Pitcher, U.S. Dept.
of Commerce. Growth Projection for Ceramic Clay Industry, November 5, 1979,
18. Reference 5.
19. Reference 17.
20. Telecon. Rader, R.D., Radian Corporation with Joe Lawless, U.S.
Department of Commerce. Growth Projection for Ceramic Clay Industry.
November 15, 1979.
4-14
-------
21. Reference 8.
22. Dobler, Rubert H., "Growth and Stability for Sanitaryware in
1978-79". Ceramic Industry Magazine. June 1978. p. 24.
23. Reference 20.
24. Reference 6.
25. Svec, J.J. "Ceramic Industry Forecast". Ceramic Industry Magazine.
June 1975. p. 25.
26. Reference 20.
27. Reference 6.
28. Reference 20.
29. Reference 6.
30. Reference 20.
31. Reference 6.
32. Reference 20.
33. Reference 17 and 20.
34. U.S. Environmental Protection Agency. Compilation of Air Pollutant
Emission Factors. AP-42 Factors for Brick Manufacture. 2nd edition.
February 1976.
4-15
-------
5. AIR EMISSIONS DEVELOPED IN SOURCE CATEGORY
Section 5.1 identifies the types and quantities of emissions from
individual emissions sources in the ceramic clay industry. Emissions
from a typical uncontrolled plant and from a plant controlled to meet a
typical State Implementation Plan are estimated in this section. An
estimate of the total national emissions from the ceramic clay industry
is presented in Section 5.2.
The information presented in this chapter is based on source test
data. There is a scarcity of source test data for this industry. State
regulatory agencies generally believe that the ceramic clay industry is
not a source of significant emissions and therefore have not required
extensive source testing. The availability of emissions data is discussed
in more detail in Chapter 7. Emission factors from EPA Document AP-42,
Compilation of Air Pollutant Emission Factors, are included for comparison
with the reported test data.
5.1 PLANT AND PROCESS EMISSIONS
The major point sources of emissions from a ceramic clay plant are
the storage silos, the kilns, and the spray booths. Sources of fugitive
emissions include the following:
Materials transfer points
Mixing and blending operations
Storage bins
Materials conveying operations
Friction and isostatic presses
Spray booths for applying glaze
Product drying and cooling operations.
5-1
-------
Any new plant that has an on-site clay crushing or grinding operations
in addition to the above operations, may have these sources regulated by
a New Source Performance Standard for non-metallic minerals presently
being developed. About 28 percent of the ceramic wall and floor tile
industry could be regulated under this standard.
5.1.1 Point Source Emissions
Point sources are sources which emit pollutants to the atmosphere
via a stack or vent. Storage silos, kilns, and spray booths are the
primary point sources in the ceramic clay industry.
5.1.2 Storage Silos. Emissions from storage silos consist mainly
of particulates. Most silos are loaded by a pneumatic conveying system.
These pneumatic conveying systems are an indirect result of the Mine
Safety and Health Act of 1977, and also serve to reduce labor costs.
The Mine Safety and Health Act of 1977 requires flint suppliers to ship
by hopper cars which require pneumatic unloading. All plants which have
a pneumatic conveying system have installed fabric filters to clean the
conveying air before it is discharged to the atmosphere. Since the
pneumatic conveyors transport the materials in an air stream, the plants
would lose most of the raw materials if the bag filters were not used.
One source test is available and reports uncontrolled particulate
emissions as 1.27 IDS/ton product (0.64 kg/Mg), and controlled emissions
as 0.016 Ibs/ton product (0.008 kg/Mg). However, this source test was
not conducted with a method approved by the EPA. It was a measurement
of particulates collected in on-line filters located upstream and
downstream of the fabric filter and the results may not be reliable.
The fabric filters are considered an integral part of the process
equipment because without it there would be a great loss of valuable raw
material. It is possible that fabric filters would not be considered as
an air pollution control device. If not considered as a control device,
the discharge from the fabric filter would be the source of uncontrolled
emissions with emissions of 0.016 Ibs/ton (0.008 kg/Mg) of product.
5-2
-------
5.1.1.2 Kilns. All kilns in this source category are fired with
natural gas. Many kilns have a standby fuel of #2 fuel oil or propane,
but these are rarely used. Because they use natural gas for firing and
because operating temperatures are low and combustion is well controlled, the
emissions from kilns are relatively free from combustion pollutants such
as NO S09, HC, or CO. Particulate emissions from the clay body may
/\ £.
occur during the drying and firing in the kiln. One noncriteria pollutant
which may be emitted is hydrogen fluoride. One to two producers contacted
add calcium fluoride to their glaze composition, and when the glazed
body is fired some of the fluoride will be volatized. Little is known
about the evolution of fluoride from the kilns. The addition of calcium
fluoride to the glazes is not a widespread practice.
Table 5-1 presents the source test data which is available on kilns.
This table also presents emission factors from AP-42 for brick kilns.
Uncontrolled particulate emissions ranged from 0 to 2.5 Ibs/ton (1.25 kg/Mg)
of product, and averaged 1.6 Ibs/ton (0.8 kg/Mg). The reported values of
2.5 and 0 Ibs/ton of product seem high and low, respectively. Because
the amount of emissions being measured is very low, measurement errors
are more common. As a comparison, AP-42 reports a particulate emission
factor of 0.04 Ibs/ton (0.02 kg/Mg) for brick kilns. Brick clay is not
as refined as the clay body material used in this industry, nor is the
brick glazed. Therefore, emissions from ceramic kilns would be expected
to be lower than from brick kilns. No plant contacted reported any
direct control devices on the kiln exhaust. Some plants use the exhaust
from the kiln for drying followed by a particulate control device. Only
one plant contacted reported such a system.
5.1.1.3 Spray Booths. Emissions from spray booths consist mainly
of particulates resulting from glaze overspray. Emissions of hydrocarbons
were a concern in the past because of the use of organic solvents in the
glazes. However, the telephone survey and plant visits revealed that
glazes are now prepared with water as a base, thus organic emissions have
been eliminated. None of the plants contacted used organic solvents in
preparing glazes. No source test data is available on the extent of
hydrocarbon emissions from current operations.
5-3
-------
TABLE 5-1. SUMMARY OF SOURCE TEST DATA
ON EMISSIONS FROM GAS FIRED KILNS2*3'4
Plant E
Plant F
Plant G
Plant H
AP-42
Uncontrolled Emission Factors
Parti culates
Ibs/ton
(kg/Mg)
0.4
(0.2)
N/A
2.5
(1.25)
2 5
(1*25)
2.5
(1.25)
0
(0)
0.04
(0.02)
so
Ibs/ton
(kg/Mg)
0.7
(0.35)
N/A
N/A
N/A
N/A
0
(0)
N
N0x
Ibs/ton
(kg/Mg)
N/A
N/A
N/A
N/A
N/A
0
(0)
0.15
(0.075)
HC
Ibs/ton
(kg/Mg)
N/A
N/A
N/A
N/A
N/A
0
(0)
0.02
(0.01)
CO
Ibs/ton
(kg/Mg)
N/A
N/A
N/A
N/A
N/A
0
(0)
0.04
(0.02)
Controlled
Emission
Factors
Parti culates
Ibs/ton
(kg/Mg)
N/A
0.13
(0.065)
N/A
N/A
N/A
N/A
N/A
N/A = Not Available
N = Negligible
5>4
-------
There is one source test on emissions from spray booths. It was
provided by industry but it was not done by an EPA test method. Uncon-
trolled particulate emissions were reported to be 0.015 Ibs/ton product
(0.0075 kg/Mg), while controlled emissions were 0.0003 Ibs/ton product
(0.00015 kg/Mg).5 The data which was gathered from the NEDS report and
the various state agencies indicate that no spray booth has controlled
particulate emissions greater than 5 TPY. This data includes emissions
for 80 spray booths.
Tennessee currently uses a particulate emission factor of 0.025
Ibs/ton (0.0125 kg/Mg) for controlled emissions from spray booths. An
average collection efficiency of 98 percent was used to determine a
factor for uncontrolled emissions.
5.1.2 Fugitive Emissions
Fugitive emissions are emissions resulting from attrition losses
during materials handling. Fugitive emissions can also result from
leaks or openings in process equipment. Although test data are available
for some of the fugitive sources listed above, emissions from these
sources are usually difficult to measure. Test data reported for these
sources are presented in Table 5-1 and 5-2.
5.1.2.1 Materials Transfer Points. Fugitive emissions from materials
transfer points result from the charging of raw materials from a conveyor
to some piece of process equipment. Mixer and blender charging operations
account for most of the emissions from this source. Because the Mine
Safety and Health Act of 1977 requires flint suppiers to ship by bulk or
covered railroad hopper cars, many plants in the ceramic clay industry
have installed pneumatic conveying systems. Of the plants which provided
process data, 52 percent had pneumatic systems. All plants contacted
had dust collection systems on transfer points. These systems have
virtually eliminated the emissions from this source. There are no test
data available to quantify emissions from material transfer points.
5.1.2.2 Mixing and Blending Operations. Mixing and blending
operations are used to produce a uniform body composition. Although
water is usually added in this process, some particulate emissions may
5-5
-------
TABLE 5-2. SUMMARY OF SOURCE TEST DATA ON
PARTICULATE EMISSIONS FROM MIXERS6'7'8
Plant A
Plant B
Plant C
Uncontrolled emissions
Ibs/ton prod.
0.13
5.5
46.6
75.0
0.83
kg/Ma P^d.
0.065
2.75
23.3
37.5
0.42
Controlled emissions
Ibs/ton prod.
N/A
0.11
0.93
1.50
0.019
kg/Mg prod.
N/A
0.055
0.465
0.75
0.01
N/A = Not Available
5-6
-------
occur. Table 5-2 summarizes the source test data on mixers. Using
weighted values, the average value of uncontrolled particulate emissions
is 17.3 IDS/ton (9 kg/Mg) of product, while controlled emissions average
0.52 Ibs/ton (0.26 kg/Mg). During the plant visits no visible emissions
from this source were observed. Because plant observations revealed no
visible emissions, and because nothing is known about the test methods
employed, some of the emissions values reported in Table 5-2 may not be
representative.
5.1.2.3 Storage Bins. Particulate emissions from storage bins
occur only when the storage bins are exposed to drafts or during the
transfer of materials. All storage bins observed during plant visits
had coverings, and no visible emissions were apparent from this source.
No test data are available on this fugitive emission source.
5.1.2.4 Materials Conveying. Particulate emissions from the
conveying of materials originate from open conveyors. Fifty-two percent
of the plants contacted in the ceramic clay industry have installed
pneumatic conveying systems and have eliminated this source of fugitive
emissions. There is one emission test available for this source, however,
the test method used is not an EPA approved test method. Particulate
emissions were measured with a filter device. Uncontrolled particulate
emissions were reported as 0.27 Ibs/ton product (0.14 kg/Mg) while
Q
controlled emissions were only 0.0061 Ibs/ton (0.003 kg/Mg).
5.1.2.5 Friction and Isostatic Presses. Friction pressing is used
in the wall and floor tile industry to form dry clay into tiles.
Isostatic pressing is used to form some electric insulators from dry
clay. These processes result in fugitive emissions because they use dry
clay (maximum of 6.5 percent moisture) from which particulates become
airborne. Table 5-3 summarizes the source test data on friction presses.
Uncontrolled particulate emissions ranged from 0.66 to 52 Ibs/ton (0.33
to 26 kg/Mg) of product, however controlled emissions ranged from only
0.04 to 1.04 Ibs/ton (0.02 to .52 kg/Mg) product. Again, no visible
emissions were observed during plant visits. Test methods are not
reported, therefore some of the emissions values may not be representative.
5-7
-------
TABLE 5-3. SUMMARY OF SOURCE TEST DATA ON
PARTICULATE EMISSIONS FROM PRESSES10'11'12
Plant B
Plant C
Plant D
Uncontrolled emissions
Ibs/ton prod.
52
4.4
0.66
kg/Mg prod.
26
2.2
0.33
Controlled emissions
Ibs/ton prod.
1.04
0.04
N/A
kg/Mg prod.
0.52
0.02
N/A
5-8
-------
5.1.2.6 Spray Booths. Although spray booths are considered point
sources, the possibility of fugitive emissions also exists. The spray
booths are box shapes varying in size and shape but generally with an
open face on one side and an exhaust on the backside. The article is
placed or conveyed inside the booth and either hand sprayed or automati-
cally sprayed with glaze. If the spray booth is not operating properly,
some particulates may escape. All of the plants visited had either
baffles or water curtain type devices on the spray collected from the
booths. During the plant visits no emissions were observed from this
source. No source test data are available on this fugitive emissions
source.
5.1.3 Emissions From a Typical Plant
This section discusses the emissions, both uncontrolled and controlled,
from a typical plant in the ceramic clay industry. The average production
rate for plants in this industry is 2270 tons of product per year (2059
Mg/yr). The greatest emission sources in a typical plant are the storage
silos, kilns, spray booths, mixers, and presses.
Table 5-4 summarizes the emission factors that were estimated using
the available data. Emission factors are presented for uncontrolled and
controlled emissions and for emissions from a typical plant controlled
to meet typical SIP control levels.
Uncontrolled particulate emissions from the greatest sources in a
typical ceramic clay plant total 40.5 Ibs/ton (20.25 kg/Mg) of product.
The total uncontrolled emissions from a typical ceramic clay plant would
be about 46 tons per year (42 Mg/yr).
All plants contacted in the ceramic clay industry reduce emissions
beyond that level required by the typical SIP plan. Under current
controls, the greatest sources in a ceramic clay plant emit only 2.7 Ibs/ton
(1.35 kg/Mg) of product. According to industry personnel emissions are
reduced for material recovery, product quality, and to maintain a clean
working environment. Annual total emissions from the greatest sources in
a typical plant are only 3.1 tons per year (2.8 Mg/yr).
5-9
-------
TABLE 5-4. PARTICULATE EMISSION FACTORS FOR
A TYPICAL CERAMIC CLAY INDUSTRY PLANT
Emissions
Source
Storage silos
Gas Fired Kiln
Spray Booth
Mixers
Presses
TOTAL
Uncontrolled Emissions
Ibs/ton kg/tog
1.27
1.6
1.3
17.3
19
40.5
0.64
0.8
0.65
8.7
9.5
20.3
Controlled Emissions
Ibs/ton kg/Mg
0.016
1.6a
0.013
0.52
0.54
2.69
_____ _
0.008
0.8a
0.0065
0.26
0.27
1.35
Typical SIP .
Control Level
Ibs/ton kg/Mg
7.35 3.68
7.35 3.68
7.35 3.68
17. 3C 8.7
19C 9.5
59.8 29.9
There is no control equipment on the gas fired kiln.
^Based on average allowable process emissions rates from Table 8-2.
Fugitive emissions are not typically regulated except by "reasonable
precaution" to prevent their emissions. Emissions were considered as
fugitive.
5-10
-------
5.2 TOTAL NATIONAL EMISSIONS FROM THE CERAMIC CLAY INDUSTRY
This section presents an estimate of the total national emissions
from the ceramic clay industry. The method used to calculate these
emissions is also presented.
Total national particulate emissions from the non-electrical portion
of the ceramic clay industry are estimated to be 872 tons per year
(791 Mg/yr). National emission from the porcelain electrical supplies
are not estimated because national production figures were not available.
The break down by industry segment of this national emission rate is
presented in Table 5-5. As shown in Section 5.1 no other pollutants are
emitted in significant quantities. Particulate emissions from the
porcelain electrical supplies industry are not included in this estimate
because of a lack of data. This estimate does however, include the
particulate emissions from the other five industrial classifications.
Nationwide emissions were estimated using the following procedure:
1. Each plant within each SIC that had available emissions data
18
was located within the EIS plant list to find its corresponding
percentage of national market.
2. Each plant's emission data within a SIC were added together to
arrive at a total emission level for that SIC.
3. Each plant's corresponding percentage of national market was
then added.
4. The total emissions were then divided by the corresponding sum
of percentage of national market to arrive at a national emissions level
for each SIC.
5. The emission levels for each SIC were then added to arrive at
a total national emission level.
The best available emission data represents source test data if it
was available but in some cases emission factors had to be used.
5.3 SUMMARY
Emissions from the ceramic clay industry consist mainly of particu-
lates. Point sources identified in the ceramic clay industry are the
storage silos, kilns, and spray booths. The greatest sources of fugitive
5-11
-------
TABLE 5-5. NATIONAL EMISSION RATE BY SIC CODE13'14'15'16'17
National
SIC Code Emission Rate
SIC 3253
Ceramic Wall and Floor Tile 32.7 TRY
SIC 3261
Vitreous China Plumbing Fixtures 226.0 TRY
SIC 3262
Vitreous China Table and Kitchen Articles 70.0 TRY
SIC 3263
Fine Earthenware Table and Kitchen Articles 22.3 TRY
SIC 3264
Porcelain Electrical Supplies ND
SIC 3269
Pottery Products, Not Elsewhere Classified 521.0 TRY
TOTAL ' 872.0 TRY
ND - Not Determinable
5-12
-------
emissions are the mixers and presses. Uncontrolled particulate emissions
from these sources total 40.5 Ib/ton (20.25 kg/Mg) of product. The
ceramic clay industry currently reduces these emission to 2.7 Ibs/ton
(1.35 kg/Mg).
Total national particulate emissions from the non-electrical portion
of the source category are 872 tons per year (791 Mg/yr). This represents the
emissions from 285 plants in the ceramic clay industry. This results in
an average emission of only 3.1 tons per year (2.8 Mg/yr) of particulates
per plant.
Source test data is scarce in the industry, and the accuracy of the
data is questionable. The amounts of particulates being measured are
small and conducive to errors. Even though some of the data seem to
show high values, the emissions from these plants are expected to be small.
The average plant which produces 2270 tons of product per year (2059 Mg/yr)
emits only 46 tons of particulates per year (42 Mg/yr) when uncontrolled.
The largest plants (30,000 TPY) would emit 608 tons of particulates per
year (552 Mg/yr) uncontrolled. However, with the control equipment
currently in use in the ceramic clay industry, these 608 tons (552 Mg/yr)
of emissions are reduced to 41 tons per year (37 Mg/yr).
5-13
-------
5.4 REFERENCES
1. Trip Report. Robertson-American Corporation, Morrisville, Pennsylvania,
December 13, 1979. Prepared by David Pierce, Radian Corporation.
2. Telecon. Pierce, D. R., Radian Corporation and Mr. Johnson.
Department of Environmental Resources, Division of Air Pollution
Control, Commonwealth of Pennsylvania. November 19, 1979.
3. Reference 1.
4. U.S. Environmental Protection Agency. Compilation of Air Pollutant
Emission Factors. 2nd edition. February 1967.
5. Reference 1.
6. National Emissions Data System Report. October 15, 1979.
7. Air Pollution Source Management System Report. New York Department
of Environmental Conservation. October 30, 1979.
8. Reference 1.
9. Reference 1.
/
10. Reference 7.
11. Reference 1.
12. Private Communication. Stamper, Henry A., Monarch Tile Manufacturing,
Inc., to Rader, R.D., Radian Corporation. December 20, 1979.
13. Economic Information Systems, Inc., EIS Industrial Plants. Dialog
Database. Lockheed, Inc., File 22. October 31, 1979.
14. Kentucky Emission Inventory System. Kentucky Division of Air
Pollution Control. November 6, 1979.
15. Trip Report. Hall China Company, East Liverpool, Ohio. December 11,
1979. Prepared by Roger D. Rader, Radian Corporation.
16. Reference 1.
17. Reference 6.
18. Reference 13.
5-14
-------
6. EMISSION CONTROL SYSTEMS
This section discusses the current types of air pollution control
equipment used in the ceramic clay industry to control particulate
emissions. No S02, NO , or other gaseous emission control systems are
used in the industry because the emission levels are negligible.
Although the equipment discussed in this section is considered to be
air pollution control equipment, industry personnel have indicated it
was not for these reasons the equipment had been installed. Wet scrubbers
and baffles were installed on glazing operations over 40 years ago to
maintain a clean work environment, for product quality control, and to
protect production equipment. Likewise, the fabric filters and vacuum
systems used to collect and remove particulate matter from various
processes were installed as an integral part of a conveying system which
reduces labor costs and/or maintains a clean work environment for the
worker and protects the quality of the product.
6.1 CURRENT CONTROL TECHNIQUES
Fabric filtration is the most commonly used technique to control
particulate emission from ceramic clay manufacturing processes. Dust
from materials handling, transferring, conveying, friction presses,
mixers and blenders is collected via a vacuum system and routed to a
fabric filter to reclaim or remove the particulates. Electrostatic
Precipitators (ESP) have not been used in the industry and will not be
discussed further in this study.
Wet cyclones and baffles are used on the glaze spray booth operations
to recover or control the particulate emissions. These are liquid
particles (aerosols) as compared to the mineral particles discussed
above.
6-1
-------
6.1.1 Fabric Filtration1'2
In fabric filtration, participate matter is removed from the carrier
gas stream by the impingement and adhesion of the particle onto the
filter medium. As particles collect on the media, the deposits themselves
act as filter media enhancing removal. When the deposits become so
thick that the pressure necessary to force the gas through the filters
becomes very high the filter is replaced or cleaned.
Fabric filters used in this industry have reported removal effici-
encies of 97 to 99+ percent.
6.1.2 Wet Cyclones3'4
Wet cyclones mix water with the incoming particles to increase
particle diameter and density. Therefore, as the particles enter the
cyclone they undergo a greater drag and inertia! force. The shape of
the cyclone creates a vortex as the gas stream enters it. The larger
particles and water droplets are forced to the outer walls where the
particles are removed with the water. The cleaned gas stream is vented
from the center of the vortex to the atmosphere. The units used in the
industry have been reported to have a particulate removal efficiency of
approximately 98 percent.
6.1.3 Baffles5'6
Baffle equipment operates similar to wet cyclones without the use
of water. The inertial forces developed in the baffle arrangement cause
the particulates to impinge on the baffles. The particles are removed
from the baffles and recycled to various processes or are disposed.
These units have a reported efficiency of approximately 98 percent as
applied in the ceramic clay industry.
6.2 ALTERNATIVE CONTROL TECHNIQUES
Other than the application of higher efficiency fabric filters and
wet scrubbers, there are no alternate control techniques demonstrated
for the particulate emissions from this industry.
6-2
-------
6.3 "BEST SYSTEMS" OF EMISSION REDUCTION
The best systems for control or reduction of emissions in the
ceramic clay industry consists of the following: (1) an enclosed material
storage and the use of covered unloading and conveying systems; (2) the
use of hoods around material transfer points, dry presses, cooling and
drying areas and other sources of particulate emissions to contain the
emissions and the use of vacuum systems to collect and convey these
emissions to fabric filters to remove the emissions from the air stream;
and (3) the use of hoods around spray glazing operations to contain
emissions and.a vacuum system to convey the emissions to a wet scrubber
to remove the emissions from the air stream. See Figure 6-1. All the
plants contacted in the industry have controls on their spray glaze
operations and 95 percent of the plants contacted have some form of dust
collection system.
6-3
-------
Fabric
Filter
If
hopper storage
for
raw
materials
Forming and Firing Operations
p
Fabric
Filter
1 1
Storage
Of
raw
materials
T__J
nixing
-H r"
spray
booth
cyclone
o pneumatic conveying
o * vacuum exhaust system
t partlculate eaisslons
t fugitive partlculate emissions
gaseous emissions
effluent
Glazing Operation
Figure 6-1. "Best" System for Emission Reduction
-------
6.4 REFERENCES
1. Stern, Arthur C., Wohlers, Henry C, Beubel, Richard W., Loury,
William P. Fundamentals of Air Pollution, Academic Press, New York
1973, Pg. 406 to 416.
2. Lund, Herbert L., Industrial Pollution Control Handbook, McGraw-
Hill Book Company, New York, 1971, Pg. 23-9 to 23-28.
3. Reference 1.
4. Reference 2.
5. Reference 1.
6. Reference 2.
6-5
-------
7. EMISSION DATA
Section 7.1 discusses the availability and nature of emission data
for the ceramic clay industry. Section 7.2 lists the sample collection
and analysis methods available for determining the emissions of particu-
lates, hydrocarbons and fluorides from various processes in the ceramic
clay industry.
7.1 AVAILABILITY OF DATA
7.1.1 Summary of Available Test Data
Although a large quantity of data were gathered during this study,
very little of the data were source test data. Information from the
National Emission Data System (NEDS) and the. state agencies yielded
source test data on 6 kilns, 4 mixing operations, and 1 friction press.
The rest of the state and NEDS data were either conflicting with one another
or concerning some process outside the scope of this report or were estimates
n
of emissions. Although the Compliance Data System (CDS) report was
helpful in providing information on compliance, it did not provide any
actual test data. Finally, the industrial contacts were an important,
but limited, source of source test data for emissions from clay processing
operations.
The reason for the lack of source test data is that many states do
not consider any of the sources in the ceramic clay industry as being
significant. Telephone contacts with state agencies concerning this
matter have been documented in the project files. Texas and Ohio have
exempted plants from requiring a permit to operate their kilns.
The following sections discuss the availability and quality of test
data obtained from specific data sources. The emission test data obtained
in this study have been presented in Chapter 5.
7-1
-------
7.1.2 National Emission Data System (NEDS)
The National Emission Data System (NEDS) provides a nationwide
compilation of data from emission sources in the ceramic clay industry.
Useful information presented in NEDS includes controlled emissions
rates, the test method used, the control equipment and their efficiencies,
process descriptions, and stack parameters. Each state is responsible
for submitting emission data to this system. However, the information
in NEDS is not always the most current and was found to conflict with
data from other sources.
The NEDS obtained for this study listed 77 different ceramic clay
plants. However, source test results were reported for only 16 plants.
Furthermore the data from only three of these plants were considered
consistent with one another. The distribution of plant data among the
six SIC codes is presented in Table 7-1. The emission data retrieved
from NEDS is presented in Chapter 5.
7.1.3 Compliance Data System (CDS)
The CDS reports information on the compliance status of air pollution
sources. This information is kept by the EPA, Office of Enforcement,
and can be retrieved by SIC code number. The data provide the compliance
status and a brief description of the point source. However, CDS does
not report actual source test results or emission data. Because the
Compliance Data System relies on information from the states, it may not
contain the most recent data. The CDS data used in this study provided
compliance data on 74 plants. No plants were reported in non-compliance.
7.1.4 State or Local Agencies
State and local air control agencies will have the most recent
source test data outside of that data directly available from industry
sources, or the NEDS system.
Other information, such as permit applications or recent emission
problems with a plant, can usually be obtained from the agency air
pollution control files. The data for a plant usually will include
stack parameters, control equipment and their efficiencies, a process
7-2
-------
TABLE 7-1. SUMMARY OF NEDS REPORT
SIC
Classification
Ceramic Wall and
floor tile (3253)
Vitreous plumbing
fixtures (3261)
Vitreous china food
utensils (3262)
Fine earthenware
food utensils (3263)
Porcelain electrical
supplies (3264)
Pottery products, not
elsewhere classified
(3269)
TOTAL
Number of plants
in NEDS
24
10
3
1
18
21
77
Number of plants
with source test data
5
0
2
0
5
4
16
7-3
-------
description, compliance status, controlled and uncontrolled emissions,
test or calculation methods used, and whether emission data is from a
source test or otherwise.
Data for this study were gathered from six states - New York,
Pennsylvania, Ohio, Kentucky, Texas and California. The distribution of
plants in these states and the availability of test data from the state
agencies is presented in Table 7-2.
7.1.5 Industrial Contacts
Industry contacts were used to fill gaps left by the other data
sources. This was the best source for up-to-date and specific source
test data.
The major producers in each industrial classification were contacted
by phone and by letter to obtain general process information. The
distribution, by industry classification, of plants contacted for this
study is presented in Table 7-3. From the list of plants contacted
plants were chosen for on-site visits to obtain specific process and air
pollution control data. Those plants visited were felt to be representa-
tive of the ceramic clay industry and to incorporate the best control
technology.
7.2 SAMPLE COLLECTION AND ANALYSIS
The EPA has established reference test methods for sampling and
analytical methods to determine particulate, hydrocarbon, and hydrogen
fluoride emissions. A complete description and presentation of each
method can be found in 40 CFR Part 60. Following are the recommended
methods for sampling and analysis of emissions from the ceramic clay
industry.
7-4
-------
TABLE 7-2. SUMMARY OF STATE DATA RECEIVED
SIC
Classification
Ceramic wall and
floor tile (3253)
Vitreous plumbing
fixtures (3261)
Vitreous china food
utensils (3262)
Fine earthenware
food utensils (3263)
Porcelain electrical
supplies (3264)
Pottery products, not
elsewhere classified
(3269)
Number of plants
in these states
15
9
1
0
7
19
Number of
in these
with source
4
0
1
0
0
0
plants
states
test data
TOTAL
51
7-5
-------
TABLE 7-3. SUMMARY OF INDUSTRIAL CONTACTS
Industry Number of plants Percentage of
Segment Contacted industry segment
Ceramic wall and
floor tile (3253)
Vitreous plumbing
fixtures (3261)
Vitreous china food
utensils (3262)
Fine earthenware
food utensils (3263)
Porcelain electrical
supplies (3264)
Pottery products, not
elsewhere classified
(3269)
TOTAL
8
9
9
3
5
14
48
35.58
35.87
82.97
31.31
ND
'
27.74
ND
ND - Not Determinate - national production figures
are not available.
7-6
-------
Method 1: Sample and Velocity Traverses for Stationary Sources
Method 2: Determination of Stack Gas Velocity and Volumetric Flowrate
Method 3: Gas Analysis for C0«, 0«, Excess Air, and Dry Molecular
Weight c c
Method 5: Determination of Particulate Emissions from Stationary Sources
Method 13a: Determination of Total Fluoride Emissions from Stationary
Sources - SPADNS Zirconium Lake Method
This method determines the fluoride concentration by measuring the
absorbance of the sample with a spectrophotometer. Once the absorbance
is determined the fluoride concentration can be found on a calibration
curve.
Method 13b: Determine of Total Fluoride Emissions from Stationary
Sources - Specific Ion Electrode Method
This method determines the fluoride concentration by measuring the
intensity of the electric field between a reference electrode and a
fluoride sensing electrode when immersed in the sample. This electric
intensity can be used to find the fluoride concentration on a calibration
curve.
Method 25: Determination of Total Gaseous Non-Methane Organic Emissions
as Carbon.
7-7
-------
7.3 REFERENCES
1. National Emissions Data System. October 15, 1979.
2. Compliance Data System Computer Printout. November 20, 1979.
7-8
-------
8. STATE EMISSION REGULATIONS
State regulations applicable to the ceramic clay industry are
summarized below for nine states. These regulations apply to approximately
70 percent of the ceramic clay industry as defined in this study. To
illustrate values obtained under the various state regulations an example
plant will be defined with a capacity of 0.4 tons/hr (0.36 Mg/hr), a kiln
burning 5 MBtu/hr of natural gas operating 24 hrs/day, 7 day/wk, 52
wk/yr and having a stack 29 feet (8.8 m) high, a diameter of 2.0 ft (0.6 m)
o
with a gas flow of 7600 acfm (215 m /min) and an exit temperature of
300°F (149°C).
This is 65 percent larger than the typical plant discussed in
Chapter 5. This plant was chosen because it is one of the plants in the
ceramic clay industry with complete data on its equipment and fuel
consumption. Emission rates from this plant, both uncontrolled and
controlled, will be compared to the allowable emissions rate under the
most stringent state regulation. Emissions rates from this plant are
based upon the emission factors from Table 5-4.
Since natural gas is the primary fuel for plants in the industry
and alternative fuels are not desirable, only natural gas firing will be
considered.
8.1 PARTICULATE EMISSION REGULATIONS
Table 8-1 summarizes the particulate emission regulations of the
nine selected states. Table 8-2 summarizes the allowable emission rate
by state regulations based upon the example plant described above.
Table 8-1 contains four types of particulate emission regulations:
opacity, fugitive, combustion, and process. Opacity or "Visible Emissions"
regulations regulate the opacity or degree of visibility of emissions in
units of percent opacity or the Ringelman scale. "Fugitive emissions"
8-1
-------
TABLE 8-1. SUMMARY OF SELECTED STATE PARTICULATE EMISSION REGULATIONS
State
Visible
Emissions
(Opacity)
Fugitive
Emissions
Participates
From Combustion
Particulates
From Process
Georgia
00
po
California
(South Coast
Air Quality
Management
District)
Ohio
Emissions are to be
less than 20* Opacity.
Emissions are to be
less than 20% Opacity.
No discharge from any
single source of emis-
sion shall be equal to
or darker than No.' 1
Ringelmanh chart or
20% Opacity.
Persons shall take all
reasonable precautions
to prevent fugitive
dust including instal-
lation and use of hoods,
fans, and fabric fil-
ters; covering of open
bodied material when
storing or conveying.
NA
Persons shall take
reasonable precau-
tions to prevent such
emissions including:
application of water
chemicals etc; use of
hoods, fans and con-
trol equipment;
covering of materials
when stored or 1n
motion.
For Fuel Burning Equipment with less
than 10 million BTU heat input per
hour E = 0.5. For equipment with
greater than 10 and less than 250
million BTU heat input per hour E = 0.5
(10/R)
For equipment greater than
250 million Btu heat input per hour
A = 0.10 Ibs/million Btu input.
For total combustion contaminants the
allowable emissions rate 1s .1 grains
per cubic foot of gas calculated at
12 percent CO. (Particulates are not
regulated separately)
For fuel burning equipment no parti -
culate emission shall exceed those in
Figure 1. (For 14 R £ 10, Allowable
emissions are 0.4 Ibs/million Btu
heat input.)
Allowable rates of emission for new
equipment is E = 4.1 Pu'b/ for P up to ..
and including 30 tons/hr and E = 55 P
- 40 for P greater than 30 tons/hr.
For Koalin and Fuller's Earth Processes
E = 3.59 P°-6f,for P*30 tons/hr and
E = 17.31 r°-16 for P > 30 tons/hr.
Allowable emission rates approximately
given by Table.
Allowable rates of emissions are
E = 4.10 P0-67 for P <> 30 and
E = 55.0 P0-11 - 40 for P * 30.
NA = Not available.
-------
TABLE 8-1. (continued)
State
Pennsylvania
New Jersey
New York
Tennessee
Visible
Emissions
(Opacity)
No person sl*all emit
visible emissions
equal to or greater
than 201 opacity.
No person shall emit
from stack or chimney
emissions greater
than 201 Opacity.
excluding water vapor.
No person shall allow
emissions having an
average opacity of
201 or greater.
No person shall
cause or allow the
discharge of emis-
sions from any
source greater than
No. 1 Rlngelmann or
20t Opacity.
Fugitive
Emissions
Any person shall take
reasonable precautions
to prevent emissions
Including adding water
or chemicals on
Material stockpiles.
None
V
None
No person shall
cause of allow emis-
sions without taking
reasonable precautions
including use of water
or chemicals or hoods.
fans and fabric
filters.
Partlculates
From Combustion
No person shall discharge emissions from
combustion In excess of 0.4 Its/mil lion
Btu heat Input when 2.5* R* 50 million
Btus/hr or A 3.6 R'0-56 when
50* R* 600.
No person shall discharge emissions
from combustion In excess of the allow-
able set forth In the table. (For heat
Input of 1 million Btu/hr E - 0.6, for
heat Input of 10 million Btu/hr E
6.0 Btu/hr.)
Does not apply.
The maximum allowable participate emis-
sions for new fuel burning equipment
shall be determined as:
A - 0.6 for R * l6«
A - 0.6 (10/R)0-5566 for 10* R* 250
A - 0.1 for RK2SO.
Particulates
From Process
Ho person shall emit partleulate matter
from any process effluent gas exceeding
0.04 grains per dry standard cubic foot
when volume < 150.000 dscf.
No person shall discharge emissions from
any source through stack or chimney in
excess of the allowable set forth In the
table. (For potential emission rate from
source of 50 Ibs/hr E 00.5 (9» eff.).
for 100 Ibs/hr E 1 .0; For source gas
of 3000 scfm or less, E - 0.5 for 6000 scfm
E - 6.0: Largest of the two Is to be, used.
No person shall discharge emissions from
any source In excess of the allowable
as determined by E - 0.024 P°-67 for P
up to 100,000 Ib/hr.
The allowable emission level from any
new process shall be determined as
E 3.5g P°-«Ifor PA 30
E 17.31 P°'16 for P> 30.
oo
GO
-------
TABLE 8-1. (continued)
00
I
4s,
State
Vest Virginia
Texas
Visible
Emissions
(Opacity)
No person shall
cause or allow
emissions of smoke
from any fuel
burning unit
darker than No. 1
Ringelmann or
equivalent
opacity.
No person shall cause
or allow visible
emissions from any
stationary flue to
exceed 201 opacity
over a 5-minute
period.
Fugitive
Emissions
No person shall cause
or allow any source
to operate that Is not
equipped with a fugi-
tive matter control
system.
No person shall cause
or allow any material
to be handled or con-
veyed without taking
precaution to prevent
fugitive emissions In-
cluding the use of
water or chemicals or
hoods, fans and filters
Particulars
From Combustion
No person shall cause or allow the dis-
charge of emissions from fuel burning
units to exceed the allowable as deter-
mined by:
E * 0.09 ft as long as no more than 600
Ibs/hr total will be discharged from all
gas fired units.
No person shall cause or allow emissions
to exceed the allowable as determined
by E 0.048 q°-6Z where q is gas flow
in acfm.
Participates
From Process
No person shall cause or allow the
discharge of emissions from process to
exceed the maximum allowable 1n the
table. (For SOOO Ibs/hr process weight
E 5, for 10.000 Ib/hr E 10 and
for 20.000 Ibs/hr E 16.
No person shall cause or allow emissions
to exceed the allowable as determined
by E 3.12 pO-985 for p A 20
E 25.4 pO-287 for p ^ 20i
Legend
C Allowable emissions In gr/dscf.
A Allowable emissions in Ibs/million Btu.
E Allowable Emission Rate (Ibs/hr).
P - Process Weight (tons/hr).
R » heat input (million Btu/hr).
Q » gas flow rate in dscfm.
-------
TABLE 8-2. ALLOWABLE EMISSION RATES FROM THE NINE SELECTED STATES FOR THE EXAMPLE PLANT
State
Georgia
California
co OMO
tn Pennsylvania
New Jersey
New York
Tennessee
West Virginia
Texas
Visible
Emissions
<20S opacity
<20t opacity
<20S opacity
<20t ooacitv
<20X opacity
*20X opacity
<-202 opacity
<20t opacity
<20t opacity
Fugitive
Emissions
Control
material
unloading and
loading and
conveyi ng
operations.
Same
Same
Same
-
-
Same as
Georgia
Must have
control
Same as
Georgia
Participate
from
Combustion
0.5 Ibs/hr
DMA
2.0 Ibs/hr
2.0 Ibs/hr
3.0 Ibs/hr
DNA
3.0 Ibs/hr
0.45 Ibs/hr
12.2 Ibs/hr
Particulate
ProSs . Wx S0x
2.2 Ibs/hr 8.4 Ibs/hr 69.61 Ibs/hr
2.2 Ibs/hr MA
2.2 Ibs/hr
2.6 Ibs/hr - 11.9 Ibs/hr
1.3 Ibs/hr - 47.7 Ibs/hr
2.1 Ibs/hr DNA
2.0 Ibs/hr DNA
0.8 Ibs/hr
1.3 Ibs/hr
CO HC Fluoride
NA NA NA
_
_
_
- -
17.7 Ibs/hr
DNA = Does not apply.
NA-Not available.
-------
are visible emissions other than water droplets coming from any source
other than a stack, vent or exhaust. "Combustion Emissions" are those
emissions coming from the burning of fuels, in this case natural gas.
"Process Emissions" are those emissions from the stacks or vents of
production processes other than those from the burning of fuel.
8.1.1 Opacity and Fugitive Emissions Regulations
All the states require visible emissions to be less than 20 percent
opacity.
West Virginia has the most stringent regulations on fugitive
emissions. West Virginia regulations require some form of control. Two
other states, New Jersey and New York have no regulations on fugitive
emissions. The remaining states require reasonable precaution to be
taken to prevent fugitive emissions. Fugitive emission regulations
would apply to material unloading and loading operations, mixing, blendings
and conveying.
8.1.2 Process Emission Regulations
Table 8-2 illustrates the allowable process emission rate for the
nine selected states. Values ranged between 2.6 to 0.8 Ibs/hr (1.2 to
0.4 kg/hr) with an average of 1.7 Ibs/hr (0.8 kg/hr).
The particulate emission regulations of West Virginia are the most
stringent of the nine selected states; at a rate of 0.80 Ibs/hr (0.4
kg/hr). The least stringent rate is Pennsylvania's 2.6 Ibs/hr (1.2 kg/hr).
These regulations would apply to particulate emissions from the storage
silos, glaze spray booths and the non-combustion emission from the
kilns.
8.1.3 Combustion Emission Regulations
The allowable combustion particulates emission rates for the nine
states are illustrated in Table 8-2. Values range from 0.45 to 12.2
Ibs/hr (0.2 to 5.5 kg/hr) with an average of 3.6 Ibs/hr (1.6 kg/hr),
excluding New York which exempts natural gas fired units. West Virginia
and Georgia require the most stringent controls allowing 0.45 and 0.50
Ibs/hr (0.2 kg/hr) respectively. Texas is the least stringent with a
value of 12.2 Ibs/hr (5.5 kg/hr) allowable. Since natural gas is used,
8-6
-------
particulate emissions are neglible and reported particulate emission
from kilns are taken as being from the product rather than from the
combustion of fuel.
Table 8-3 illustrates that the uncontrolled particulate emissions
from the industry presently meet the most stringent allowable rates
allowed by any of the nine selected states. Therefore, the industry
would not be affected by these regulations. In addition, the industry
further reduces these emissions as shown in Table 8.3. Industry personnel
have said that reduction is necessary to maintain the quality of the
product and to protect the workers' health.
8.2 GASEOUS EMISSION REGULATIONS
Table 8-4 summarizes the nine selected state regulations of gaseous
emissions. Since natural gas is primarily used in the ceramic clay
industry, emissions do not require the control or degree of control as
would be required if less clean fuels were used. Many states exempt
equipment burning natural gas or other gas fuels from regulations entirely.
In addition, regulations generally apply to fuel-burning equipment with
greater than 250 million Btu/hr heat input, well above any sources in
this industry. States regulations with this stipulation were assumed
not to apply to this industry. Georgia is the only state of the nine
that has general regulations for the emission of NO . Georgia's regula-
A
tions in general would allow less than 21 Ibs/ton (11 kg/Mg) of NO
rt
emissions from any source. Georgia, Pennsylvania and New Jersey have
regulations on SO emissions. Pennsylvania SO regulations are the most
/\ J\
stringent. In general their regulations would allow less than 30 Ibs/ton
(15 kg/Mg) of SO emission from any source. None of the 9 state regulations
n
reviewed have process regulations on carbon monoxide and hydrocarbons.
Several states have regulations on volatile organic compounds,
but these would generally not apply to this industry because wide-spread
use of water-based glazes.
Fluoride emissions have occurred in the ceramic clay industry and
for this reason some investigation of fluoride emissions was made in
this study. As Table 8-4 shows, Texas is the only state with regulations
8-7
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TABLE 8-3. SUMMARY OF CONTROL REQUIRED BY THE NINE SELECTED STATE PARTICULATE REGULATIONS
Emission Source
Uncontrolled
Emission Rate
Most Stringent
SIP Control
Current
Control Level'
Storage Silos
Gas Fired Kiln
Spray Booths
Fugitive
1.27 Ibs/ton (0.6 kg/Mg)
1.6 Ibs/ton (0.8 kg/Mg)
1.3 Ibs/ton (0.7 kg/Mg)
36.3 Ibs/ton (18.1 kg/Mg)
2 Ibs/ton (1 kg/Mg)
2 Ibs/ton (1 kg/Mg)
2 Ibs/ton (1 kg/Mg)
NAb
0.016 Ibs/ton (0.008 kg/Mg)
1.6 Ibs/ton (0.8 kg/Mg)
0.013 Ibs/ton (0.007 kg/Mg)
1.06 Ibs/ton (0.53 kg/Mg)
00
Based on West Virginia Regulation for example plant of .4 tons/hr.
00 West Virginia is only state that requires fugitive emission control but has no limits
reported.
cln general, all plants in the industry currently have controls that reduce uncontrolled
emissions to these levels.
-------
TABLE 8-4. SUMMARY OF SELECTED STATE REGULATIONS ON GASEOUS EMISSIONS
Sttte
NO.
SO.
CO
Hydrocarbons
Georgia
For Fuel Burning Equipment equal to
or greater than 250 alllion Btu/hr
heat input when firing gas 0.2 Ibs
of HO. per Million Btu of heat In-
put. Tto person shall allow NO
emissions except from fuel burning
equipment equal to or exceeding: for
HA 300; N 9300 (H/300)3. A
weighted average If tare than one
stack Is located at a given site.
From any source of emission SO.
shall not equal or exceed for (
H« go, S 1.2 FxBt for 90* H< 300,
S 4000 F (H/300)3. Hew source
regulations with heat Input >2SO
Million Btu's/hr heat Input apply
only to liquid and solid fossil fuels.
None
None
California
Ohio
Pennsylvania
New Jersey
VO
HA
Does not apply.
None
HA
None
No person shall emit SO from any source
exceeding 500 ppm In effluent gas by volume.
No person shall discharge SO. emissions
from stack or chimney exceeding 2000 ppm
by volume, If total gas volume Is greater
than 3000 icfm, SO. discharge Is greater
than SO Ibs/hr and the maximum exceeds
100 Ibs/hr.
HA
None
None
None
HA
Hone
None
None
New York
Tennessee
Nest Virginia
Texas
Does not apply.
Does not apply.
None
None
None
None
None
None
Hone
None
None
None
None
None
None
None
Legend
N total NO, (Ibs/hr).
HA Hot available.
F a constant (1 for non combustion sources. 2 for heat Input A 10.000
million Btu/hr, and 3 If> 10,000 million Btu/hr).
S Ibs/hr of S0{ from stick.
H stack height In feet.
-------
on fluoride emissions. Fluoride is not a common emission from the
ceramic clay industry. Some glazes have fluoride as a constituent but
according to data received it is small quantities and poses no problem.
In addition no plant contacted during this study used fluoride in their
glazes. Using the example plant described above, Texas regulations
would allow an emission rate of 17.7 Ibs/hr (8.0 Kg/hr) of fluoride. A
state agency emission data system reported the largest level of fluoride
emissions for a plant in the industry. Although it is not source test
data, but rather an AP-42 emission factor, it reports an emission rate
of 1.2 Ibs/hr (0.5 Kg/hr), or just greater than 5 tons per year (4.5
Mg/hr). No fluoride emission controls would be required for this emission
source.
8-10
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TECHNICAL REPORT DATA
(Please read Instruction* on the reverse before completing)
'R
EEWPJ§0/3-80-017
2.
3. RECIPIENT'S ACCESSION NO.
4. Tl
SURVEY: CERAMIC CLAY INDUSTRY
5. R
6. PERFORMING ORGANIZATION CODE
17. AUTHOR(S)
I. PERFORMING ORGANIZATION REPORT NO.
9. PE
OuaTily pfanmng and Standards
Environmental Protection Agency
Research Triangle Park, N. C. 27711
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-02-3058
SPONSORING AGENCY NAME AND ADDRESS
DAA for Air Quality Planning and Standards
Office of Air, Noise and Radiation
U.S. Environmental Protection Agency
Research Triangle Park, N. C. 27711
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
EPA/200/04
IS. SUPPLEMENTARY NOTES
16. ABSTRACT
This report contains background information which was used for determining
the need for new source performance standards (NSPS) for the ceramic clay
industry in accordance with Section 111 of the Clean Air Act. Air pollution
emissions and growth trends of the ceramic clay industry are examined.
Manufacturing processes, control techniques, and state and local air
pollution regulations are discussed.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b. IDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Croup
Air Pollution
Pollution Control
Ceramic Clay
Ceramics Manufacture
New Source Performance Standards
Air Pollution Control
13B
18. DISTRIBUTION STATEMENT
UNLIMITED
19. SECURITY CLASS (This Report)
UNCLASSIFIED
21. NO. OF PAGES
68
20. SECURITY CLASS (This page)
UNCLASSIFIED
22. PRICE
EPA Form 2220-1 (R«w. 4-77) PREVIOUS EDITION is OBSOLETE
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