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/ 2002
/ June
/ Thursday, June 20, 2002
[Federal Register: June 20, 2002 (Volume 67, Number 119)]
[Proposed Rules]
[Page 42107-42170]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr20jn02-36]
[[Page 42107]]
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Part II
Environmental Protection Agency
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40 CFR Part 63
National Emission Standards for Hazardous Air Pollutants for Refractory
Products Manufacturing; Proposed Rule
[[Page 42108]]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 63
[FRL-7222-9]
RIN 2060-AG68
National Emission Standards for Hazardous Air Pollutants for
Refractory Products Manufacturing
AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.
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SUMMARY: This action replaces Refractories Manufacturing with
Refractory Products Manufacturing on the list of categories of major
sources of hazardous air pollutants (HAP) published under section
112(c) of the Clean Air Act (CAA) and on the source category schedule
for national emission standards for hazardous air pollutants (NESHAP).
This action also proposes NESHAP for new and existing refractory
products manufacturing sources. The proposed rule would require all
major sources to meet emission standards reflecting the application of
maximum achievable control technology (MACT). The proposed rule would
protect air quality and promote the public health by reducing emissions
of several of the HAP listed in section 112(b)(1) of the CAA, including
ethylene glycol, formaldehyde, hydrogen fluoride (HF), hydrochloric
acid (HCl), methanol, phenol, and polycyclic organic matter (POM).
Exposure to these substances has been demonstrated to cause adverse
health effects such as irritation of the lung, skin, and mucous
membranes, effects on the central nervous system, and damage to the
liver, kidneys, and skeleton. The EPA has classified the HAP
formaldehyde and POM as probable human carcinogens. We estimate that
the proposed rule would reduce nationwide emissions of HAP from these
facilities by as much as 120 megagrams per year (Mg/yr) (132 tons per
year (tons/yr)).
DATES: Comments. Submit comments on or before August 19, 2002.
Public Hearing. If anyone contacts the EPA requesting to speak at a
public hearing by July 10, 2002, a public hearing will be held on July
22, 2002.
ADDRESSES: Comments. By U.S. Postal Service, send comments (in
duplicate, if possible) to: Air and Radiation Docket and Information
Center (6102), Attention Docket Number A-2000-50, U.S. EPA, 1200
Pennsylvania Avenue, NW., Washington, DC 20460. In person or by
courier, deliver comments (in duplicate if possible) to: Air and
Radiation Docket and Information Center (6102), Attention Docket Number
A-2000-50, Room M-1500, U.S. EPA, 401 M Street, SW., Washington DC
20460. The EPA requests that a separate copy of each public comment be
sent to the contact person listed below (see FOR FURTHER INFORMATION
CONTACT). Comments may also be submitted electronically by following
the instructions provided in SUPPLEMENTARY INFORMATION.
Public Hearing. If a public hearing is held, it will be held at 10
a.m. at the EPA Office of Administration Auditorium, Research Triangle
Park, North Carolina.
Docket. Docket No. A-2000-50 contains supporting information used
in developing the proposed standards. The docket is located at the U.S.
EPA, 401 M Street, SW., Washington, DC 20460 in Room M-1500, Waterside
Mall (ground floor), and may be inspected from 8:30 a.m. to 5:30 p.m.,
Monday through Friday, excluding legal holidays.
FOR FURTHER INFORMATION CONTACT: Susan Zapata, Minerals and Inorganic
Chemicals Group, Emissions Standards Division (C504-05), U.S. EPA,
Research Triangle Park, North Carolina 27711, telephone number (919)
541-5167, electronic mail (e-mail) address: zapata.susan@epa.gov. For
questions about the public hearing, contact Ms. Tanya Medley, Minerals
and Inorganic Chemicals Group, Emission Standards Division (C504-05),
U.S. EPA, Research Triangle Park, North Carolina 27711, telephone
number (919) 541-5422, e-mail address: medley.tanya@epa.gov.
SUPPLEMENTARY INFORMATION: Comments. Comments and data may be submitted
by e-mail to: a-and-r-docket@epa.gov. Electronic comments must be
submitted as an ASCII file to avoid the use of special characters and
encryption problems and will also be accepted on disks in
WordPerfect. All comments and data submitted in electronic
form must note the docket number: A-2000-50. No confidential business
information (CBI) should be submitted by e-mail. Electronic comments
may be filed online at many Federal Depository Libraries.
Commenters wishing to submit proprietary information for
consideration must clearly distinguish such information from other
comments and clearly label it as CBI. Send submissions containing such
proprietary information directly to the following address, and not to
the public docket, to ensure that proprietary information is not
inadvertently placed in the docket: Attention: Susan Zapata, c/o OAQPS
Document Control Officer, C404-02, U.S. EPA, Research Triangle Park, NC
27709. The EPA will disclose information identified as CBI only to the
extent allowed by the procedures set forth in 40 CFR part 2. If no
claim of confidentiality accompanies a submission when it is received
by the EPA, the information may be made available to the public without
further notice to the commenter.
Public Hearing. Persons interested in presenting oral testimony or
inquiring as to whether a hearing is to be held should contact Ms.
Tanya Medley at least 2 days in advance of the public hearing. Persons
interested in attending the public hearing must also call Ms. Medley to
verify the time, date, and location of the hearing. The public hearing
will provide interested parties the opportunity to present data, views,
or arguments concerning these proposed emission standards.
Docket. The docket is an organized and complete file of all the
information considered by the EPA in the development of this
rulemaking. The docket is a dynamic file because material is added
throughout the rulemaking process. The docketing system is intended to
allow members of the public and industries involved to readily identify
and locate documents so that they can effectively participate in the
rulemaking process. Along with the proposed and promulgated standards
and their preambles, the contents of the docket, with certain
exceptions, will serve as the record in the case of judicial review.
(See section 307(d)(7)(A) of the CAA.) The regulatory text and other
materials related to the proposed rulemaking are available for review
in the docket or copies may be mailed on request from the Air Docket by
calling (202) 260-7548. A reasonable fee may be charged for copying
docket materials.
World Wide Web (WWW). In addition to being available in the docket,
an electronic copy of today's proposed rule will also be available on
the WWW through the Technology Transfer Network (TTN). Following
signature, a copy of the rule will be posted on the TTN's policy and
guidance page for newly proposed or promulgated rules at http://
www.epa.gov/ttn/oarpg. The TTN provides information and technology
exchange in various areas of air pollution control. If more information
regarding the TTN is needed, call the TTN HELP line at (919) 541-5384.
Regulated Entities. Categories and entities potentially regulated
by this action include:
[[Page 42109]]
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Category SIC NAICS Examples of regulated entities
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Industrial...................................... 3255 327124 Clay refractories manufacturing plants.
Industrial...................................... 3297 327125 Nonclay refractories manufacturing plants.
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This table is not intended to be exhaustive, but rather provides a
guide for readers regarding entities likely to be regulated by this
action. To determine whether your plant site is regulated by this
action, you should examine the applicability criteria in Sec. 63.9782
of the proposed rule. If you have any questions regarding the
applicability of this action to a particular entity, consult the person
listed in the preceding FOR FURTHER INFORMATION CONTACT section.
Outline. The information presented in this preamble is organized as
follows:
I. Background
A. What is the source of authority for development of NESHAP?
B. What criteria are used in the development of NESHAP?
C. What is the history of the source category?
D. What is refractory products manufacturing?
E. What are the health effects of pollutants emitted from the
Refractory Products Manufacturing source category?
II. Summary of the Proposed Rule
A. What source category is affected by the proposed rule?
B. What are the primary sources of emissions from major sources
and what are the emissions?
C. What are the affected sources?
D. What are the emission limits?
E. What are the operating limits?
F. What are the work practice standards?
G. What are the testing and initial compliance requirements for
sources subject to emission limits?
H. What are the initial compliance requirements for sources
subject to a work practice standard?
I. What are the continuous compliance requirements for sources
subject to emission limits?
J. What are the continuous compliance requirements for sources
subject to a work practice standard?
K. What are the notification, recordkeeping, and reporting
requirements?
III. Rationale for Selecting the Proposed Standards
A. How did we select the source category and any subcategories?
B. How did we select the emission sources to be regulated?
C. How did we define the affected sources?
D. How did we determine the proposed standards for existing
sources?
E. How did we select the emission limits for new sources?
F. How did we select the format of the standard?
G. How did we select the testing and initial compliance
requirements?
H. How did we select the continuous compliance requirements?
I. How did we select the notification, reporting, and
recordkeeping requirements?
IV. Summary of Environmental, Energy and Economic Impacts
A. What are the air quality impacts?
B. What are the water and solid waste impacts?
C. What are the energy impacts?
D. What are the cost impacts?
E. What are the economic impacts?
V. Administrative Requirements
A. Executive Order 12866, Regulatory Planning and Review
B. Executive Order 13132, Federalism
C. Executive Order 13175, Consultation and Coordination with
Indian Tribal Governments
D. Executive Order 13045, Protection of Children from
Environmental Health Risks and Safety Risks
E. Executive Order 13211, Actions Concerning Regulations that
Significantly Affect Energy Supply, Distribution, or Use
F. Unfunded Mandates Reform Act of 1995
G. Regulatory Flexibility Act (RFA), as Amended by the Small
Business Regulatory Enforcement Fairness Act of 1996 (SBREFA), 5
U.S.C. 601 et seq.
H. Paperwork Reduction Act
I. National Technology Transfer and Advancement Act
I. Background
A. What Is the Source of Authority for Development of NESHAP?
Section 112 of the CAA requires us to list categories and
subcategories of major sources and area sources of HAP and to establish
NESHAP for the listed source categories and subcategories. The category
of major sources covered by today's proposed rule was listed as
Chromium Refractories Production on July 16, 1992 (57 FR 31576). Major
sources of HAP are those that have the potential to emit greater than
10 tons/yr of any one HAP or 25 tons/yr of any combination of HAP.
B. What Criteria Are Used in the Development of NESHAP?
Section 112 of the CAA requires that we establish NESHAP for the
control of HAP from both new and existing major sources. The CAA
requires the NESHAP to reflect the maximum degree of reduction in
emissions of HAP that is achievable. This level of control is commonly
referred to as the MACT.
The MACT floor is the minimum control level allowed for NESHAP and
is defined under section 112(d)(3) of the CAA. In essence, the MACT
floor ensures that the standard is set at a level that assures that all
major sources achieve the level of control at least as stringent as
that already achieved by the better-controlled and lower-emitting
sources in each source category or subcategory. For new sources, the
MACT floor cannot be less stringent than the emission control that is
achieved in practice by the best-controlled similar source. The MACT
standards for existing sources can be less stringent than standards for
new sources, but they cannot be less stringent than the average
emission limitation achieved by the best-performing 12 percent of
existing sources in the category or subcategory (or the best-performing
five sources for categories or subcategories with fewer than 30
sources).
In developing MACT, we also consider control options that are more
stringent than the floor. We may establish standards more stringent
than the floor based on the consideration of cost of achieving the
emissions reductions, any health and environmental impacts, and energy
requirements.
C. What Is the History of the Source Category?
We published an initial list of source categories on July 16, 1992
(57 FR 31576). Chromium Refractories Production was included on the
initial source category list as a major source category. After
obtaining and analyzing information on HAP emissions from chromium
refractories manufacturing plants, we determined that some facilities
were major sources due to HAP emissions from the manufacturing of
nonchromium refractories at these plants. Because the production of
nonchromium refractories at those facilities would not be covered by
other source categories on the current source category list, we decided
to expand the scope of the chromium refractories production source
category to include most manufacturers of refractory products.
Section 112(c) of the CAA allows EPA to revise the source category
list at any time. On November 18, 1999, we revised the source category
name from Chromium Refractories Production to Refractories
Manufacturing (64 FR 63025) to reflect the broadened scope of the
source category. Today's action changes the source category name from
Refractories Manufacturing to Refractory
[[Page 42110]]
Products Manufacturing on the source category list under section 112(c)
of the CAA to further clarify the source category.
D. What Is Refractory Products Manufacturing?
Refractory products are heat-resistant materials that provide the
linings for high-temperature furnaces, reactors, and other processing
units. They include, but are not limited to: Kiln furniture, crucibles,
refractory ceramic fiber (RCF), and materials used as linings for
boilers, kilns, and other processing units and equipment where extremes
of temperature, corrosion, and abrasion would destroy other materials.
Refractory products manufacturing facilities generally can be
classified based on the different types of raw materials and process
operations used. In the broadest sense, refractory products can be
classified by raw materials as either clay refractories or nonclay
refractories. Chromium refractories are a subset of nonclay refractory
products. Classifications of refractory products by process operations
include monolithics, resin-bonded refractories, pitch-impregnated
refractories, pitch-bonded refractories, other formed refractories that
use organic additives, RCF, and fused-cast refractories. Table 1 of
this preamble contains abbreviated definitions of each of these
classifications.
Table 1.--Refractory Products Classifications
------------------------------------------------------------------------
Classification Product type Description
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By raw material............... Clay............. Products that
contains at least 10
percent clay in the
raw material mix.
Nonclay.......... Products that contain
less than 10 percent
clay in the raw
material mix.
By process.................... Monolithics...... Products that consist
of a mixture of
granular refractory
raw materials that
have not been shaped
or formed.
Resin-bonded..... Cured products that
are produced using a
phenolic resin or
other type of HAP-
forming resin as a
binder.
Pitch-impregnated Fired products that
are subsequently
impregnated with
coal tar or
petroleum pitch.
Pitch-bonded..... Cured products that
are produced using
coal tar or
petroleum pitch as a
binder.
Other formed Dried or cured
products that products that are
are produced products that are
using organic produced using an
additives. organic binder other
than resins, coal
tar, or petroleum
pitch.
RCF.............. Spun or blown bulk
RCF and products
that consist
primarily of RCF.
Fused-cast....... Products manufactured
by casting a molten
refractory raw
material mix into a
form.
------------------------------------------------------------------------
There are approximately 167 domestic refractory products
manufacturing plants currently in operation located in 30 States and
Puerto Rico. In terms of the number of facilities, the leading States
are Ohio (40 plants), Pennsylvania (28 plants), Illinois (13 plants),
and Missouri (10 plants). Most of these facilities are not likely to be
major sources of HAP.
To produce most refractory products, raw materials are mixed,
formed into shapes, dried or cured, then fired at high temperature in a
kiln. The raw materials used in the refractory can be classified as
either body materials or binders and additives. The body materials used
in the industry are either raw or processed minerals, the most common
of which are clays, silica, alumina, magnesium oxide, bauxite, silicon
carbide, mullite, and graphite. The percentage of clay used in the
mixture defines whether the product is a clay or nonclay refractory
product.
Binders are substances that are added to a granular material to
give it workability and green or dry strength. Nonclay refractory
products generally require binders, whereas clay refractories may not
need binders due to the cohesive nature of clay and the presence of
moisture in the clay. Binders can also serve as lubricants and can
impart other properties to the final product. For example, in addition
to acting as binders, phenolic resins and pitch also increase product
lifetime and durability by adding carbon that remains in the refractory
body after firing. Additives are used to facilitate processing and/or
impart specific properties to the final product. The most widely used
binders and additives are cement, water, silicates, inorganic acids,
phenolic resins, pitch, and lignin compounds, such as calcium
lignosulfonate.
Clays and other raw minerals that are used as body materials in
refractory products manufacturing require mechanical processing, such
as grinding and screening, prior to their use. After processing, body
materials, binders, and additives are proportioned and mixed.
Monolithics typically require no further processing other than bagging
or packaging for shipment. Other types of refractory products must be
formed into shapes by pressing, extruding, molding, or casting. Next,
the formed shapes generally are dried or cured at temperatures of
90 deg. to 260 deg.C (200 deg. to 500 deg.F). Drying and curing are
similar processes with respect to equipment design and operation; the
primary difference between the two processes is that the function of
drying is to reduce the free moisture content of the shapes, whereas
curing activates the resin or binder in the shapes. The final step in
the production of most refractory shapes is firing. Firing serves three
primary functions: to reduce the number of pores in the refractory; to
increase the density of the refractory; and to bond together the
individual refractory grains into a strong, hard mass. Firing typically
is performed in either tunnel kilns, which operate continuously, or in
periodic kilns, which operate as a batch process. Most firing
temperatures are in the range of 1090 deg. to 1540 deg.C (2000 deg. to
2800 deg.F) and the entire firing cycle typically takes 24 to 36 hours.
After firing, the shapes may be finished by grinding, cutting to
specification, or other process; the shapes then are packaged for
shipment.
Some refractory products manufacturing facilities impregnate fired
shapes with coal tar or petroleum pitch to add additional carbon to the
body to increase the durability of the finished product. This process
includes the simultaneous heating of pitch in a
[[Page 42111]]
pitch working tank and heating of fired shapes in a shape preheater to
between 150 deg. and 260 deg.C (300 deg. and 500 deg.F); placing the
shapes and pitch in a sealed vessel, typically called an autoclave; and
applying pressure to force the pitch into the pores of the shapes.
After impregnation, the shapes are cooled (defumed). For certain
applications, the impregnated shapes undergo an additional process
referred to as coking. In the coking process, the shapes are placed in
a coking oven and heated under reducing conditions to drive off the
volatile constituents (i.e., POM) of the pitch.
To produce fused-cast refractories, raw materials are mixed and
loaded into an electric arc furnace where the mixture is heated to a
molten state. The molten material is then poured into molds and allowed
to cool before any final cutting, grinding, or finishing operation.
The production of RCF involves process steps that differ
significantly from the steps used to produce formed refractory
products. To manufacture RCF, alumina, silica, and calcined kaolin are
mixed and fed into a melting furnace. As the molten material pours or
drains from the furnace, it is fiberized into long, thin fibers by
blowing or spinning. The fibers can then be chopped and shipped as bulk
fibers, needled into fiber blankets, or cast into formed fiber
products.
Based on the available data, we have concluded that no existing
facilities that produce fused-cast refractory products or RCF are major
sources of HAP emissions. In addition, we have determined that none of
the existing facilities that produce only monolithics are major HAP
sources. Therefore, facilities that produce only these types of
refractory products would not be regulated under today's rule as
proposed.
E. What Are the Health Effects of Pollutants Emitted From the
Refractory Products Manufacturing Source Category?
The HAP that would be controlled by the proposed rule are
associated with a variety of adverse health effects. These adverse
health effects include chronic health disorders (e.g., irritation of
the lung, skin, and mucous membranes, gastrointestinal effects, and
damage to the kidneys and liver) and acute health disorders (e.g.,
respiratory irritation and central nervous system effects such as
drowsiness, headache, and nausea). The EPA has classified two of the
HAP (formaldehyde and POM) as probable human carcinogens.
The EPA does not have the type of current detailed data on each of
the facilities and the people living around the facilities covered by
today's proposed rule for this source category that would be necessary
to conduct an analysis to determine the actual population exposures to
the HAP emitted from these facilities and the potential for resultant
health effects. Therefore, EPA does not know the extent to which the
adverse health effects described above occur in the populations
surrounding these facilities. However, to the extent the adverse
effects do occur, and this proposed rule reduces emissions, subsequent
exposures would be reduced.
Following is a discussion of the health effects of seven HAP:
ethylene glycol, formaldehyde, HF, HCl, methanol, phenol, and POM.
Although the proposed rule would reduce emissions of HF and HCl from
any new kilns that emit these HAP, it would not reduce emissions of
these HAP from existing sources. We estimate that emissions of methanol
from existing sources would also not be reduced by today's proposed
rule. However, methanol is a constituent of some resins used in resin-
bonded refractory production, and today's proposed rule would regulate
methanol emissions from any affected source that began producing
refractory products made with resins that contain methanol.
1. Ethylene Glycol
Acute (short-term) exposure of humans to ethylene glycol by
ingesting large quantities causes central nervous system depression
(including drowsiness and respiratory failure), gastrointestinal upset,
cardiopulmonary effects, and renal damage. The only effects noted in
the one available study of humans acutely exposed to low levels of
ethylene glycol by inhalation were throat and upper respiratory tract
irritation. Rats and mice exposed chronically (long-term) to ethylene
glycol in their diet exhibited signs of kidney toxicity and liver
effects. No information is available on the reproductive or
developmental effects of ethylene glycol in humans, but several studies
of rodents have shown ethylene glycol to be fetotoxic. The EPA has not
classified ethylene glycol for carcinogenicity.
2. Formaldehyde
Both acute and chronic exposure to formaldehyde irritates the eyes,
nose, and throat, and may cause coughing, chest pains, and bronchitis.
Reproductive effects, such as menstrual disorders and pregnancy
problems, have been reported in female workers exposed to formaldehyde.
Limited human studies have reported an association between formaldehyde
exposure and lung and nasopharyngeal cancer. Animal inhalation studies
have reported an increased incidence of nasal squamous cell cancer. The
EPA considers formaldehyde a probable human carcinogen (Group B2).
3. Hydrogen Fluoride
Acute inhalation exposure to gaseous HF can cause severe
respiratory damage in humans, including severe irritation and pulmonary
edema. Chronic exposure to fluoride at low levels has a beneficial
effect of dental cavity prevention and may also be useful for the
treatment of osteoporosis. Exposure to higher levels of fluoride may
cause dental fluorosis or mottling, while very high exposures through
drinking water or air can result in crippling skeletal fluorosis. One
study reported menstrual irregularities in women occupationally exposed
to fluoride. The EPA has not classified HF for carcinogenicity.
4. Hydrogen Chloride
Hydrogen chloride, also called hydrochloric acid, is corrosive to
the eyes, skin, and mucous membranes. Acute inhalation exposure may
cause eye, nose, and respiratory tract irritation and inflammation and
pulmonary edema in humans. Chronic occupational exposure to HCl has
been reported to cause gastritis, bronchitis, and dermatitis in
workers. Prolonged exposure to low concentrations may also cause dental
discoloration and erosion. No information is available on the
reproductive or developmental effects of HCl in humans. In rats exposed
to HCl by inhalation, altered estrus cycles have been reported in
females, and increased fetal mortality and decreased fetal weight have
been reported in offspring. The EPA has not classified HCl for
carcinogenicity.
5. Methanol
Acute or chronic exposure of humans to methanol by inhalation or
ingestion may result in blurred vision, headache, dizziness, and
nausea. No information is available on the reproductive, developmental,
or carcinogenic effects of methanol in humans. Birth defects have been
observed in the offspring of rats and mice exposed to methanol by
inhalation. A methanol inhalation study using rhesus monkeys reported a
decrease in the length of pregnancy and limited evidence of impaired
learning ability in offspring. The EPA has not classified methanol with
respect to carcinogenicity.
[[Page 42112]]
6. Phenol
Acute inhalation and dermal exposure to phenol is highly irritating
to the skin, eyes, and mucous membranes in humans. Oral exposure to
small amounts of phenol may cause irregular breathing, muscular
weakness and tremors, coma, and respiratory arrest at lethal
concentrations. Anorexia, progressive weight loss, diarrhea, vertigo,
salivation, and a dark coloration of the urine have been reported in
chronically exposed humans. Gastrointestinal irritation and blood and
liver effects have also been reported. No studies of developmental or
reproductive effects of phenol in humans are available, but animal
studies have reported reduced fetal body weights, growth retardation,
and abnormal development in the offspring of animals exposed to phenol
by the oral route. The EPA has classified phenol in Group D, not
classifiable as to human carcinogenicity.
7. Polycyclic Organic Matter
The term polycyclic organic matter defines a broad class of
compounds that includes the polycyclic aromatic hydrocarbon compounds
(PAH), of which benzo[a]pyrene is a member. Dermal exposures to
mixtures of PAH cause skin disorders in humans and animals. No
information is available on the reproductive or developmental effects
of POM in humans, but animal studies have reported that oral exposure
to benzo[a]pyrene causes reproductive and developmental effects. Human
studies have reported an increase in lung cancer in humans exposed to
POM-bearing mixtures including coke oven emissions, roofing tar
emissions, and cigarette smoke. Animal studies have reported
respiratory tract tumors from inhalation exposure to benzo[a]pyrene and
forestomach tumors, leukemia, and lung tumors from oral exposure to
benzo[a]pyrene. The EPA has classified seven PAH compounds
(benzo[a]pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene,
benzo[k]fluoranthene, dibenz[a,h]anthracene, and indeno[1,2,3-
cd]pyrene) as Group B2, probable human carcinogens.
II. Summary of the Proposed Rule
A. What Source Category Is Affected by the Proposed Rule?
Today's proposed rule would apply to the Refractory Products
Manufacturing source category. This source category includes, but is
not limited to, any facility that manufactures refractory bricks and
shapes that are produced using an organic HAP compound, pitch-
impregnated refractory products, chromium refractory products, and
fired clay refractory products. Fired refractory products are those
that have undergone thermal processing in a kiln.
B. What Are the Primary Sources of Emissions From Major Sources and
What Are the Emissions?
At most refractory products manufacturing plants, the primary
sources of HAP emissions are the thermal process units. Other sources
of HAP emissions at these facilities are the raw material processing
and handling equipment.
Thermal process units can emit several HAP, as well as a number of
criteria pollutants. The thermal process units that would be covered by
the proposed rule are: Shape dryers, curing ovens, and kilns that are
used to process resin-bonded, pitch-bonded, and other refractory
products that are produced using an organic HAP compound; defumers,
coking ovens, shape preheaters, and pitch working tanks associated with
pitch-impregnated refractory production; kilns used to fire chromium
refractory products; and kilns used to fire clay refractory products.
The HAP emitted by a specific thermal process unit depend mostly on the
raw materials, binders, and additives used. The criteria pollutants
emitted by thermal process units include particulate matter (PM),
sulfur dioxide (SO2), carbon monoxide (CO), nitrogen oxides
(NOX), and volatile organic compounds (VOC). Depending on
the type of resin or additive used, these materials can include phenol,
methanol, ethylene glycol, POM, and other organic compounds. For resin-
bonded refractory production, the thermal process units are the curing
ovens and kilns, which can emit phenol, formaldehyde, ethylene glycol,
and methanol. For pitch-bonded refractory production, the thermal
process units are the curing ovens and kilns. These sources all emit
POM, which is the primary constituent of coal tar and petroleum pitch.
For pitch-impregnated refractory production, the thermal process units
are the coking ovens, defumers, pitch working tanks, and shape
preheaters, which also emit POM. Kilns that are used to fire chromium
refractory products emit particulate chromium and several other HAP
metals. For clay refractory production, the fluorides and chlorides in
the clay form HF and HCl, respectively, which are subsequently emitted
from kilns during firing.
C. What Are the Affected Sources?
Today's proposed rule would establish emission limitations
(emission limits and operating limits) and work practice standards for
several types of refractory products manufacturing sources. Table 2 of
this preamble lists the affected sources that would be subject to the
proposed rule.
Table 2.--Sources That Would Be Affected by the Proposed Refractory
Products Manufacturing Rule
------------------------------------------------------------------------
Refractory product type Affected sources
------------------------------------------------------------------------
Resin-bonded........................... Existing and new curing ovens
and kilns.
Pitch-bonded........................... Existing and new curing ovens
and kilns.
Pitch-impregnated...................... Existing and new shape
preheaters, pitch working
tanks, defumers, and coking
ovens.
Other formed products that use organic Existing and new shape dryers
additives. and kilns used to process
refractory shapes that are
made using an organic HAP
compound.
Chromium............................... Existing and new kilns.
Clay................................... Existing and new kilns.
------------------------------------------------------------------------
D. What Are the Emission Limits?
Emission limits are numeric limits on the emissions from affected
sources. Today's proposed rule would specify separate emission limits
for affected sources of organic HAP, HF, and HCl.
1. Existing and New Thermal Process Sources of Organic HAP
Today's proposed rule would establish emission limits for specified
thermal process sources that emit organic HAP. Facilities that operate
these types of sources could meet either of two types of emission
limits: A specified minimum combustion efficiency of an add-on control
device (i.e., a thermal oxidizer or a catalytic oxidizer); or a limit
on the concentration
[[Page 42113]]
of total hydrocarbons (THC) in the emissions. The combustion efficiency
option would apply only to sources that are controlled with a thermal
or catalytic oxidizer for which the carbon dioxide (CO2)
concentration at the outlet of the device is 3 percent or less. To
comply with the combustion efficiency limit, you would be required to
reduce emissions of CO and THC so that the average combustion
efficiency is 99.8 percent or greater. If the outlet CO2
concentration is more than 3 percent, or if you choose to comply with
the THC emission concentration limit, you would be required to reduce
emissions of THC at the outlet of the source or control device to 20
parts per million by volume, dry basis (ppmvd), or less, corrected to
18 percent oxygen (O2). The sources that would be subject to
these organic HAP emission limits include new and existing shape
dryers, curing ovens, kilns, coking ovens, and defumers. In addition,
new shape preheaters would be subject to these same emission limits.
You would also be required to meet the THC emission concentration limit
if you operate an affected source that is not equipped with a thermal
or catalytic oxidizer.
For continuous process sources, the format of the combustion
efficiency and THC emission limits would be a 3-hour block average.
That is, the average combustion efficiency or THC concentration based
on three 1-hour test runs would have to meet the emission limit of at
least 99.8 percent combustion efficiency or no more than 20 ppmvd THC
at 18 percent O2, whichever applies. For batch process
sources, the format of the standard is the average of the highest
rolling 3-hour averages for three test runs. In other words, you would
have to calculate the rolling 3-hour average combustion efficiency of
THC concentration for each 3-hour period of each test run. From each of
the three test runs, you would select the highest rolling 3-hour
average. You would then determine the average of those three highest
rolling averages to determine if your source is in compliance with the
emission limit.
2. New Clay Refractory Kilns
If you own or operate an affected new clay refractory kiln, you
would be required to meet emission limits for both HF and HCl. For
affected tunnel kilns, you would have to meet an HF emission limit of
0.001 kilogram per megagram (kg/Mg) (0.002 pound per ton (lb/ton)) of
product or reduce HF emissions by at least 99.5 percent. You would also
be required to meet an HCl emission limit of 0.0025 kg/Mg (0.005 lb/
ton) of product or reduce uncontrolled HCl emissions by at least 98
percent. If you own or operate a new affected periodic kiln, you would
be required to reduce HF emissions by at least 99.5 percent and HCl
emissions by at least 98 percent.
E. What Are the Operating Limits?
Operating limits are limits on operating parameters of process
equipment or control devices. Today's proposed rule specifies process
and control device operating limits for thermal process sources that
emit organic HAP and clay refractory kilns. For each of these operating
limits, you would be required to measure the appropriate operating
parameters during the performance test and establish limits on the
operating parameters based on those measurements. Following the
performance test, you would be required to monitor those parameters and
ensure that the established limits are not exceeded.
1. Existing and New Thermal Process Sources of Organic HAP
For affected thermal process sources that discharge organic HAP, we
would require operating limits on the organic HAP processing rate and
the operating temperatures of your control devices. The operating limit
on the organic HAP processing rate would require you to measure during
the performance test the rate at which organic HAP are processed in an
affected process unit. To determine the organic HAP processing rate,
you would need data on the mass fractions of organic HAP in each resin,
binder, or additive that contains an organic HAP. You could determine
the mass fraction of organic HAP in a material using EPA Method 311,
``Analysis of Hazardous Air Pollutant Compounds in Paints and Coatings
by Direct Injection into a Gas Chromatograph.'' You could also use
material safety data sheets (MSDS) or product labels to determine the
mass faction of organic HAP in a substance.
For continuous process units, the organic HAP processing rate would
be measured in units of mass of organic HAP per unit time (e.g., pounds
of HAP per hour) contained in the refractory products that undergo
thermal processing. For batch process units, the organic HAP processing
rate would be measured in units of mass of organic HAP per mass of
refractory products that undergo thermal processing (e.g., pounds of
organic HAP per ton of refractory product in the batch). Following the
performance test, you would be required to monitor the organic HAP
processing rate and ensure that the rate does not exceed the rate
established during the performance test. If you decided to start
production of a refractory product that is likely to have an organic
HAP processing rate greater than the rate established during the most
recent performance test, you would be required to conduct a new
performance test for that product and establish a new operating limit
for the organic HAP processing rate.
For sources that are controlled with a thermal oxidizer, you would
be required to monitor the combustion chamber temperature. For affected
sources that are controlled with a catalytic oxidizer, you would be
required to monitor the temperature at the inlet of the catalyst bed.
You would also be required to maintain the catalyst according to
manufacturer's specifications. For either type of control device, you
would be required to measure and record the appropriate temperature
during the performance test. Following the performance test, you would
be required to monitor continuously the control device operating
temperature and ensure that the 3-hour block average temperature does
not fall below the corresponding temperature measured during the
performance test minus 14 deg.C (25 deg.F).
2. New Clay Refractory Kilns
If you have a new clay refractory kiln that is controlled with a
dry lime injection fabric filter (DIFF) or a dry lime scrubber/fabric
filter (DLS/FF), you would be required to monitor fabric filter inlet
temperature and lime feed rate. During the performance test, you would
be required to measure the fabric filter inlet temperature. Following
the performance test, you would be required to continuously measure
fabric filter inlet temperature and ensure that the temperature does
not exceed the temperature established during the performance test plus
14 deg.C (25 deg.F). During the performance test, you would also be
required to measure the lime feed rate and subsequently ensure that the
lime feed rate did not fall below the feed rate established during the
performance test. You would also have to verify that lime is free-
flowing to the control system. In addition, you would be required to
install a bag leak detection system, initiate corrective action within
1 hour of a bag leak detection system alarm, and complete corrective
actions according to your operation, maintenance, and monitoring (OM&M)
plan. You would also have to operate and maintain the fabric filter
such that the alarm is not engaged for more than 5 percent of the total
operating time in a 6-month reporting period. In calculating this
operating
[[Page 42114]]
time fraction, if inspection of the fabric filter demonstrates that no
corrective action is required, no alarm time would be counted. If
corrective action is required, each alarm would be counted as a minimum
of 1 hour, and if you take longer than 1 hour to initiate corrective
action, the alarm time would be counted as the actual amount of time
taken to initiate corrective action.
If you use a DLS/FF, you would also be required to measure the
water injection rate during the performance test. Following the
performance test, you would be required to maintain the water injection
rate at least at the levels established during the performance test.
If you use a wet scrubber (WS), you would be required to measure
the pressure drop across the scrubber, liquid pH, and liquid flow rate
during the performance test. Following the performance test, you would
be required to ensure that the levels of these parameters did not fall
below the corresponding levels established during the performance test.
3. All Affected Sources
Under today's proposed rule, you would be required to prepare a
written OM&M plan and keep the plan up to date for all affected
sources. The plan would have to include procedures for the proper
operation and maintenance of each affected source and its air pollution
control device(s). The plan would also have to include procedures for
monitoring and proper operation of monitoring systems to help assure
both initial and continuous compliance with the emission limits,
operating limits, and work practice standards.
If you own or operate an affected source of organic HAP equipped
with an alternative control device or technique not listed in the
proposed rule, you would have to install a THC continuous emission
monitoring system (CEMS) on the outlet of the control device or in the
stack. You would also be required to comply with Performance
Specification (PS) 8 of 40 CFR part 60, appendix B, and with Procedure
1 of 40 CFR part 60, appendix F. If you own or operate an affected
chromium refractory products kiln or clay refractory products kiln that
is equipped with an alternative control device or technique not listed
in the proposed rule, you would have to establish operating limits for
the appropriate operating parameters subject to prior written approval
by the Administrator as described in 40 CFR 63.8(f). You would be
required to submit a request for approval of alternative monitoring
procedures that includes a description of the alternative control
device or technique, the type of monitoring device or procedure that
would be used, the appropriate operating parameters that would be
monitored, and the frequency that the operating parameter values would
be determined and recorded. You would establish site-specific operating
limits during your performance test based on the information included
in the approved alternative monitoring procedures request. You would
also be required to install, operate, and maintain the parameter
monitoring system for the alternative control device or technique
according to your OM&M plan. If the Administrator determines that
parameter monitoring cannot assure continuous compliance, a CEMS may be
required.
If you use a control device or technique listed in the proposed
rule, you could establish operating limits for alternative operating
parameters subject to prior written approval by the Administrator on a
case-by-case basis. You would be required to submit the application for
approval of alternative operating parameters no later than the
notification of the performance test. The application would have to
include information justifying the request for alternative operating
parameters (such as why using the alternative operating parameters is
preferable to using the operating parameters in the proposed rule), a
description of the proposed alternative control device operating
parameters, the monitoring approach, the frequency of measuring and
recording the alternative parameters, the averaging period for the
operating limits, how the operating limits are to be calculated, and
information documenting that the alternative operating parameters would
provide equivalent or better assurance of compliance with the relevant
emission limit. You would have to install, operate, and maintain the
alternative parameter monitoring systems in accordance with the
application approved by the Administrator.
F. What Are the Work Practice Standards?
Today's proposed rule would establish work practice standards for
existing shape preheaters that are used to produce pitch-impregnated
refractory products, existing and new pitch working tanks that are used
to produce pitch-impregnated refractory products, existing and new
chromium refractory products kilns, and existing clay refractory
products kilns.
If you operate an affected existing shape preheater, you would be
required to control emissions of POM from the shape preheater by one of
three methods. Two of the methods entail removing the residual pitch
from the surfaces of the baskets or containers that are used for
holding refractory shapes in a shape preheater and autoclave. You would
have to clean the basket surfaces at least every ten impregnation
cycles. Alternatively, you could duct the exhaust from the shape
preheater to a control device that meets the applicable emission limits
for thermal process sources of organic HAP. If you choose to clean the
basket surfaces, you would have two cleaning options. One basket
cleaning option would be to remove residual pitch by abrasive blasting,
provided that the emissions from the abrasive blasting operation are
exhausted to a fabric filter. The other basket cleaning option would be
to subject the baskets to a thermal process cycle that matches or
exceeds the temperature and cycle time of the affected shape preheater
and is ducted to a thermal or catalytic oxidizer that is comparable to
the control device for your defumer or coking oven. For example, if the
operating temperature and cycle time of your shape preheater are
200 deg.C (400 deg.F) and 2 hours, respectively, you could ``clean''
the baskets by placing them in a shape dryer that operates at a
temperature of 200 deg.C (400 deg.F) or higher for at least 2 hours and
is exhausted to a thermal oxidizer that is comparable to your defumer
thermal oxidizer. Subjecting the baskets to a thermal process with a
cycle time and temperature equal to or greater than those of the shape
preheater ensures that POM that would have been emitted from the shape
preheater otherwise is controlled. If you choose to duct shape
preheater emissions to a control device, you could duct the emissions
to the coking oven control device, defumer control device, or to
another thermal or catalytic oxidizer that is comparable to the coking
oven or defumer controls and meets the applicable emission limits for
thermal process sources of organic HAP.
If you have an affected existing or new pitch working tank, you
would be required to duct the exhaust from the tank to either the
coking oven control device, the defumer control device, or an
equivalent thermal or catalytic oxidizer. If you choose to exhaust the
working tank emissions to an alternate thermal or catalytic oxidizer,
the emissions from that control device would have to meet the
applicable emission limits for thermal process sources of organic HAP.
If you have an affected existing or new chromium refractory
products kiln or an affected existing clay refractory products kiln,
you would have to use
[[Page 42115]]
natural gas, or an equivalent fuel, as the kiln fuel.
G. What Are the Testing and Initial Compliance Requirements for Sources
Subject to Emission Limits?
Under today's proposed rule, you would be required to conduct an
initial performance test on each affected source to demonstrate initial
compliance with the emission limits. In accordance with 40 CFR
63.7(a)(2), you would be required to conduct the test within 180 days
after the compliance date using specified test methods.
1. Existing and New Thermal Process Sources of Organic HAP
If you have an affected existing or new shape dryer, curing oven,
kiln, coking oven, or defumer, or a new shape preheater, you would be
required to measure emissions of THC in stack gases exhausted to the
atmosphere using EPA Method 25A, ``Determination of Total Gaseous
Organic Concentration Using a Flame Ionization Analyzer.'' If you
choose to comply with the THC concentration limit of 20 ppmvd corrected
to 18 percent O2, you would also have to measure the oxygen
concentration of the stack gas using EPA Method 3A, ``Determination of
Oxygen and Carbon Dioxide Concentrations in Emissions From Stationary
Sources (Instrumental Analyzer Procedure).'' The oxygen concentration
data are needed for correcting the measured THC concentration to 18
percent O2. The performance test would consist of at least
three 1-hour test runs, and you would be required to measure and record
the stack gas concentrations of THC and oxygen every minute.
If the affected source is controlled with a thermal or catalytic
oxidizer, and the outlet CO2 concentration is 3 percent or
less, you could elect to comply with the combustion efficiency limit.
If you choose to comply with the combustion efficiency limit, you would
be required to measure emissions of CO using EPA Method 10,
``Determination of Carbon Monoxide Emissions From Stationary Sources,''
and CO2 using EPA Method 3A, in addition to measuring THC.
The performance test would consist of at least three 1-hour test runs,
and you would be required to measure and record the stack gas
concentrations of THC, CO, and CO2 every minute.
If your source is a continuous process, you would determine
compliance with the emission limit by first determining the hourly
average concentrations for each pollutant and diluent (i.e., THC and
O2 for the THC limit, or CO2, CO, and THC for the
combustion efficiency limit) as the numeric average of the 1-minute
concentrations for each test run. Each test run must last at least 1
hour. The minimum number of 1-minute concentration measurements needed
for each hour of testing would be 50. You would then calculate the
average concentrations for each pollutant as the mean of the three
hourly concentrations for that pollutant. To be in compliance with the
combustion efficiency limit, the average of three 1-hour average
combustion efficiencies for the test would have to be 99.8 percent or
greater.
The test methods and conditions for meeting the combustion
efficiency limit for a continuous process also apply if your source
operates as a batch process. You would also be required to measure
emissions for three test runs. However, for batch processes, each test
run would have to be conducted over all or part of separate batch
cycles.
You would be required to test throughout three complete batch
cycles unless you developed an emissions profile for the duration of
the batch cycle, or met certain conditions for terminating a
performance test run before completion of the batch cycle. If you
choose to develop an emissions profile, you would be required initially
to sample THC emissions throughout a complete batch cycle, regardless
of whether you were complying with the THC limit or the combustion
efficiency limit. You would be required to determine the hourly average
concentrations of THC, corrected to 18 percent O2, for each
hour of the batch cycle. Based on the average hourly THC
concentrations, you would identify the 4-hour period of peak emissions.
That is, the period of 4 consecutive hours when THC concentrations are
highest. During the two subsequent test runs, you would not be required
to sample emissions outside that 4-hour period of peak THC emissions.
To be in compliance with the THC emission limit, the average of the
highest rolling 3-hour average THC concentrations corrected to 18
percent O2 during the period of peak emissions for the three
test runs would have to be 20 ppmvd or less. Likewise, to be in
compliance with the combustion efficiency limit, the average of the
highest rolling 3-hour average combustion efficiencies during the
period of peak emissions for the three test runs would have to be 99.8
percent or greater. During subsequent performance tests, you would have
to complete at least three test runs, but you would only have to test
during the 4-hour period of peak emissions during each run.
If you choose not to develop an emissions profile, you could
terminate testing before the completion of a batch cycle if you met
certain conditions. For each of three test runs, you would have to
begin testing at the start of the batch cycle and continue testing for
at least 3 hours beyond the point in time when the process reaches peak
operating temperature. You could stop testing for that run at that time
if you could show that THC concentrations are not increasing over the
3-hour period since process peak temperature was reached; at least 1
hour has passed since any reduction in the operating temperature of the
control device (thermal or catalytic oxidizer); and either the average
THC concentration at the inlet to the control device for the previous
hour has not exceeded 20 ppmvd, corrected to 18 percent O2,
or your source met the emission limit during each of the previous 3
hours after the process reached peak temperature. For example, if you
were testing to show compliance with the THC limit, and the hourly THC
concentrations after peak process temperature was reached were 12 ppm,
12 ppm, and 11 ppm, respectively, you could stop that test run.
However, if the hourly THC concentrations for those 3 hours were 12
ppm, 14 ppm, and 16 ppm, respectively, you could not stop testing
because THC concentrations would still be increasing. You would have to
satisfy these testing procedures for the remaining two test runs during
two other batch cycles.
For both continuous process and batch process performance tests,
you would be required to conduct performance tests on affected thermal
process sources under the conditions that would result in the highest
levels of organic HAP emissions expected to occur for that affected
source. You would determine these ``worst-case'' conditions by taking
into account the organic HAP processing rate, the process operating
temperatures, and the processing times. The organic HAP processing rate
is the rate at which the mass of organic HAP materials contained in
refractory shapes are processed in an affected thermal process source.
For continuous process units, the organic HAP processing rate would be
measured in units of mass of organic HAP processed per hour (e.g.,
pounds of phenol per hour). For example, if a continuous curing oven is
curing 2 tons per hour (4,000 lbs/hr) of resin-bonded refractory
shapes, the refractory mix contains 5 percent resin, and the resin
contains 10 percent phenol, the organic HAP processing rate (for
phenol) is:
4,000 lbs/hr x \5/100\ x \10/100\ = 20 lbs/hr.
[[Page 42116]]
For batch processes, the organic HAP processing rate would be
measured in units of mass of organic HAP processed per batch cycle
(e.g., pounds of phenol per batch). The organic HAP processing rate
would be determined based on the amount or percentage of organic HAP in
the raw material mix and the weight of the shapes processed. You would
be required to record the total weight and cycle time of each batch.
For example, if you operate a batch process coking oven, and the oven
is loaded with 20 tons (40,000 lbs) of pitch-impregnated refractories
that contain 6 percent pitch, the organic HAP processing rate (for POM)
is:
40,000 lbs/batch x \6/100\ = 2,400 lbs/batch.
If you decided to start production of a refractory product that is
likely to have an organic HAP processing rate greater than the rate
established during the most recent performance test, you would be
required to conduct a new performance test for that product and
establish a new operating limit for the organic HAP processing rate.
You would also have to conduct a new performance test on an affected
uncontrolled kiln following any process changes that are likely to
increase kiln emissions. For example, if the kiln followed a curing
oven, and you shortened the curing oven cycle time significantly, you
would have to repeat the performance test on the kiln because the
shorter curing time could result in a decrease in organic HAP emissions
from the curing oven and an increase in organic HAP emissions from the
kiln.
If the affected source is controlled with a thermal oxidizer, you
would be required to measure the thermal oxidizer combustion chamber
temperature continuously and record the temperature at least every 15
minutes during the performance test. If the affected source is
controlled with a catalytic oxidizer, you would be required to measure
the temperature at the inlet of the catalyst bed continuously and
record the temperature at least every 15 minutes during the performance
test. You would also be required to measure and record the process
operating temperature of the affected source at least once every hour.
If the source is a batch process and is controlled with a thermal
or catalytic oxidizer, you could reduce the operating temperature of
the control device or shut the control device off under the following
conditions: (1) At least 3 hours have passed since the process unit
reached its maximum temperature; (2) the applicable emission limit (THC
concentration or combustion efficiency) has been met during each of the
three 1-hour periods since the process reached peak temperature; (3)
emissions of THC have not increased during the 3-hour period since
maximum process temperature was reached; and (4) either the average THC
concentration at the inlet to the oxidizer has not exceeded 20 ppmvd,
corrected to 18 percent O2, for at least 1 hour, or the
applicable emission limit has been met during each of the four 15-
minute periods immediately following the oxidizer temperature
reduction. In other words, if you measure THC emissions at the inlet to
the oxidizer and the data show that the THC concentration corrected to
18 percent O2 has remained 20 ppmvd or lower for at least 1
hour, you could shut off the oxidizer at the end of the third hour
following the process reaching temperature. Alternatively, you could
continue measuring emissions at the oxidizer outlet for another hour
beyond the 3-hour period that follows the peak process temperature. If
the outlet emissions met the THC or combustion efficiency limit for
four straight 15-minute periods, you could shut off the oxidizer after
the fourth 15-minute period (i.e., at the end of the fourth hour since
the process reached peak operating temperature). If the applicable
emission limit has not been met during any of the four 15-minute
periods immediately following the oxidizer temperature reduction, you
would have to return the oxidizer to its normal operating temperature
as soon as possible and maintain that temperature for at least 1 hour.
You would be required to repeat this procedure (i.e., measure emissions
for at least 1 hour and return the control device to normal temperature
if the emission limit was not met) until the source meets the
applicable emission limit for at least 1 hour.
If you elect to shut off or reduce the temperature of a thermal or
catalytic oxidizer by satisfying these conditions, you could use the
results from the performance test to establish the time at which an
oxidizer could be shut off (or temperature reduced) during the
production of other refractory products that use organic HAP. For any
such product, you would be required to operate the oxidizer at a
temperature at least as high as that established during the performance
test, minus 16 deg.C (25 deg.F), from the start of the batch cycle
until 3 hours have passed since the process reached its peak
temperature. You would have to maintain that oxidizer temperature for
the same length of time beyond the process peak temperature as during
the performance test. For example, if, during the performance test, an
affected curing oven reached peak temperature at 12 hours into the
cycle, and you satisfied all of the conditions for shutting off the
thermal oxidizer at hour 16 of the cycle (i.e., 4 hours after the
curing oven reached peak temperature), you could shut off the thermal
oxidizer 4 hours after reaching the curing oven peak temperature for
any other affected product that is cured in that curing oven. This
provision would apply to curing cycles of any duration; regardless of
the total cycle time, you would have to operate the thermal oxidizer
for at least 4 hours beyond the time at which the process reaches peak
temperature.
If you control emissions from an affected curing oven, shape dryer,
kiln, defumer, coking oven, shape preheater, or pitch working tank
using process modifications or an add-on control device other than a
thermal or catalytic oxidizer, you would be required to install a THC
CEMS. You would also be required to satisfy the requirements of PS-8 of
40 CFR part 60, appendix B.
2. New Clay Refractory Kilns
For each new kiln that manufactures clay refractory products, you
would be required to measure emissions of HF and HCl. You would measure
HF and HCl emissions using EPA Method 26A, ``Determination of Hydrogen
Halide and Halogen Emissions from Stationary Sources-Isokinetic
Method.'' You would be required to conduct the tests for HF and HCl
while the affected kiln is operating at the maximum production level
likely to occur. Each test run would have to be at least 1 hour in
duration.
If you have an affected continuous clay refractory kiln, you would
determine initial compliance with the production-based mass emission
limits for HF and HCl by calculating the mass emissions per unit of
production for each test run using the mass emission rates of HF and
HCl and the production rate (on a fired-product basis) measured during
your performance test. For HF, mass emissions per unit of production
would have to be less than or equal to 0.001 kg/Mg (0.002 lb/ton). For
HCl, mass emissions per unit of production would have to be less than
or equal to 0.0025 kg/Mg (0.005 lb/ton). To determine initial
compliance with any of the percent reduction emission limits, you would
calculate the percent reduction of the specific HAP (HF or HCl)
entering and exiting the control device for each test run using the
mass emission rates measured during your performance test. The percent
of HF reduced would have to be 99.5 percent
[[Page 42117]]
or greater, and the percent of HCl reduced would have to be 98 percent
or greater.
If you have an affected batch process clay refractory kiln, you
would have to comply with the percent reduction limit. You would be
required to test throughout three complete batch cycles unless you
developed an emissions profile. If you choose to develop an emissions
profile, you would be required to sample HF and HCl emissions
throughout one complete batch cycle. Based on the average hourly HF
percent reduction for each hour of the cycle, you would identify the
period of 3 consecutive hours over which HF emissions are highest.
During all subsequent test runs, you would not have to sample emissions
outside that 3-hour period of peak HF emissions.
For both continuous and batch process kilns, you would be required
to measure and record the average uncalcined clay processing rate for
each test run. For continuous kilns, the uncalcined clay processing
rate would be measured as the weight of uncalcined clay processed
divided by the duration of the test run (e.g., tons per hour). For
batch process kilns, the uncalcined clay processing rate would be the
weight of uncalcined clay processed per batch cycle (e.g., tons per
batch).
If you have an affected clay refractory kiln that is controlled
with a DIFF or a DLS/FF, you would be required to measure the fabric
filter inlet temperature at least every 15 minutes. You would also be
required to measure and record the lime feed rate at least hourly and
verify that lime is free-flowing to the control system.
If you have an affected clay refractory kiln that is controlled
with a DLS/FF, you would be required to measure the water injection
rate at least every 15 minutes during the performance test. If you use
a wet scrubber, you would be required to measure the pressure drop
across the scrubber, liquid pH, and liquid flow rate at least every 15
minutes during the performance test.
3. All Affected Sources
In addition to the procedures previously described, you would be
required to follow the procedures specified in EPA Methods 1 to 4 of
appendix A of 40 CFR part 60, where applicable. You would perform
Method 1, ``Sample and Velocity Traverses for Stationary Sources,'' (or
Method 1A) to select the locations of sampling points and the number of
traverse points. You would perform Method 2, ``Determination of Stack
Gas Velocity and Volumetric Flow Rate (Type S Pitot Tube),'' (or Method
2A, 2C, 2D, 2F, or 2G) to determine gas velocity and volumetric flow
rate. You would perform Method 3, ``Gas Analysis for the Determination
of Dry Molecular Weight,'' (or Method 3A or 3B) to determine the
exhaust gas molecular weight. You would perform Method 4,
``Determination of Moisture Content in Stack Gases,'' to measure the
moisture content of the exhaust gas.
Prior to the initial performance test, you would be required to
install the continuous parameter monitoring system (CPMS) that you
would need for demonstrating continuous compliance. During the
performance test, you would use the CPMS to establish the operating
limits (e.g., minimum thermal oxidizer combustion chamber temperature).
H. What Are the Initial Compliance Requirements for Sources Subject to
a Work Practice Standard?
If you own or operate an affected existing shape preheater, an
existing pitch working tank, or a new pitch working tank, you would be
required to select a method for complying with the work practice
standard and provide a description of that method as part of your
initial notification, as required by 40 CFR 63.9(b)(2) of the General
Provisions. For affected shape preheaters, if you choose to comply with
the work practice standard by removing pitch from basket or container
surfaces, you would have to describe the method of removal. If you
choose to comply by subjecting the baskets or containers to a thermal
process cycle, you would have to describe the process, the process unit
operating temperature, the process cycle time, and the emission control
system used on the process unit into which the baskets or containers
are placed. If you choose to comply by capturing and ducting emissions
from the shape preheater to a control device, you would have to
describe the design (e.g., thermal oxidizer combustion chamber
temperature and residence time) and operation of that control device.
For affected existing or new pitch working tanks, you would have to
describe in your initial notification the design (e.g., thermal
oxidizer combustion chamber temperature and residence time) and
operation of the control device to which the emissions from the working
tank are exhausted. You would also have to verify that the control
device is the same as, or is at least equivalent to, the control device
that is used to control organic HAP emissions from an affected defumer
or coking oven.
For affected new or existing chromium refractory products kilns and
for existing clay refractory products kilns, you would have to indicate
in your initial notification the type of fuel used in those kilns.
I. What Are the Continuous Compliance Requirements for Sources Subject
to Emission Limits?
Under today's proposed rule, you would be required to demonstrate
continuous compliance with each emission limitation that applies to
you. You would be required to follow the requirements in your OM&M plan
and in your startup, shutdown, and malfunction plan (SSMP) and document
conformance with both plans. For each affected source equipped with an
add-on air pollution control device (APCD), you would be required to
operate and maintain an emission capture and control system, inspect
each system at least once each calendar year, and record the results of
each inspection. You would be required to install, operate, and
maintain each required CPMS to monitor the operating parameters
established during your initial performance test. The CPMS would have
to collect data at least every 15 minutes, and you would need to record
at least one data point during three of the four 15-minute periods per
hour to have a valid hour of data. You would have to collect all data
while the process is operational. You would have to operate the CPMS at
all times when the process is operating. You would also have to conduct
proper maintenance of the CPMS (including inspections, calibrations,
and validation checks) and maintain an inventory of necessary parts for
routine repairs of the CPMS. Using the 15-minute block average recorded
readings, you would calculate and record the average hourly values of
each operating parameter. You would also be required to repeat any
required performance tests at least every 5 years.
1. Existing and New Thermal Process Sources of Organic HAP
For each affected source, you would have to monitor and maintain
the organic HAP processing rate below the level established during the
performance test. You would also be required to record the process
operating temperature hourly. For batch process sources, you would be
required to record cycle times for each batch cycle. The start of a
cycle would coincide with the heating of the process unit, and the
cycle would end when the process unit is opened for removal of the
refractory products. If you decided to start production of a refractory
product that is likely to have an organic HAP processing rate greater
than the rate
[[Page 42118]]
established during the most recent performance test, you would be
required to conduct a new performance test for that product and
establish a new operating limit for the organic HAP processing rate.
For affected continuous sources that are controlled with a thermal
oxidizer, you would be required to maintain the 3-hour block average
combustion chamber temperature at or above the combustion chamber
temperature established during the performance test minus 14 deg.C
(25 deg.F). For affected continuous sources that are controlled with a
catalytic oxidizer, you would be required to maintain the 3-hour block
average temperature at the inlet of the catalyst bed at or above the
corresponding temperature established during the most recent
performance test minus 14 deg.C (25 deg.F).
For affected batch process sources that are controlled with a
thermal oxidizer, you would be required to maintain the average hourly
combustion chamber temperature at or above the combustion chamber
temperature established during the performance test minus 14 deg.C
(25 deg.F). If you met the conditions for reducing the operating
temperature of the thermal oxidizer during the performance test and
either reduced the temperature or shut off the oxidizer, as specified
in item 13 of Table 4 of the proposed rule, you could likewise reduce
the temperature of the oxidizer during other process cycles. That is,
from the start of the cycle until 3 hours after the process unit
reaches peak temperature, you would have to maintain the hourly
combustion chamber temperature established during the performance test
for the corresponding period. If you were able to shut off the oxidizer
after this 3-hour period during the performance test, you could
likewise shut off the oxidizer for the remainder of the process cycle
following this 3-hour period after peak temperature is reached,
regardless of the cycle duration. For affected batch process sources
that are controlled with a catalytic oxidizer, the requirements would
be the same as described in the previous paragraph for thermal
oxidizers, except that you would have to maintain the temperature at
the inlet of the catalyst bed at or above the corresponding
temperature, minus 16 deg.C (25 deg.F), established during the
performance test. For any affected source controlled with a catalytic
oxidizer, you would also be required to maintain the catalyst according
to manufacturer's specifications.
To document compliance with these operating limits for thermal or
catalytic oxidizers, you would be required to measure and record the
specified average hourly temperatures. You would also be required to
report any average hourly control device operating temperature below
the corresponding temperature measured during the most recent
performance test minus 14 deg.C (25 deg.F). In such cases, you would be
required to promptly initiate and complete corrective actions in
accordance with your OM&M plan following an hourly average control
device operating temperature that is below the corresponding minimum
temperature established during the performance test minus 14 deg.C
(25 deg.F).
If you control emissions from an affected curing oven, shape dryer,
kiln, defumer, coking oven, shape preheater, or pitch working tank
using process modifications or an add-on control device other than a
thermal or catalytic oxidizer, you would demonstrate continuous
compliance by operating a THC CEMS in accordance with Procedure 1 of 40
CFR part 60, appendix F.
2. New Clay Refractory Kilns
For new clay refractory kilns that are controlled with a DIFF or
DLS/FF, you would have to continuously maintain the 3-hour block
average temperature at the fabric filter inlet at or below the average
temperature, plus 14 deg.C (25 deg.F), established during your
performance test. You would have to maintain free-flowing lime in the
feed hopper or silo at all times. You can verify that lime is free-
flowing by a visual check or by means of the output of a load cell,
carrier gas/lime flow indicator, carrier gas pressure drop measurement
system, or other system. If the lime is found not to be free-flowing,
you would have to promptly initiate and complete corrective actions.
You would also have to maintain the lime feeder setting at or above the
level established during your performance test and record the feeder
setting once each day. You would have to initiate corrective action
within 1 hour of a bag leak detection system alarm and complete
corrective actions according to your OM&M plan. You would also have to
operate and maintain the fabric filter such that the alarm is not
engaged for more than 5 percent of the total operating time in any 6-
month reporting period. In calculating this operating time fraction, if
inspection of the fabric filter demonstrates that no corrective action
is required, no alarm time would be counted. If corrective action is
required, each alarm would be counted as a minimum of 1 hour, and if
you take longer than 1 hour to initiate corrective action, the alarm
time would be counted as the actual amount of time taken to initiate
corrective action.
Additionally, for a DLS/FF, you would have to continuously maintain
the 3-hour block average water injection rate at or above the minimum
value established during your performance test. For kilns that are
controlled with a wet scrubber, you would have to continuously maintain
the 3-hour block average scrubber pressure drop, scrubber liquid pH,
scrubber liquid flow rate, and chemical addition rate (if applicable)
at or above the minimum values established during your performance
test.
Finally, you would be required to record the uncalcined clay
processing rate for all affected kilns. For continuous kilns, the
uncalcined clay processing rate would be recorded in units of mass per
unit time (e.g., pounds of uncalcined clay per hour). For batch process
kilns, you would record the uncalcined clay processing rate in units of
mass per batch cycle (e.g., pounds of uncalcined clay per batch).
J. What Are the Continuous Compliance Requirements for Sources Subject
to a Work Practice Standard?
If you have an affected existing shape preheater, an existing pitch
working tank, or a new pitch working tank, you would be required to
perform the appropriate work practice and document that you are
complying with the work practice standard in your Notification of
Compliance Status, as required by 40 CFR 63.9 of the General
Provisions. For affected shape preheaters, you would have three work
practice options: mechanically remove pitch from the basket or
container surfaces, subject the baskets or containers to a thermal
process cycle, or capture and duct emissions from the shape preheater
to a control device. The control device would have to be the same
device that controls emissions from an affected defumer or coking oven,
or a device that is comparable to the control device used for
controlling emissions from an affected defumer or coking oven. That
control device also would have to meet the applicable emission limits
for thermal process sources of organic HAP.
For affected pitch working tanks, you would have to capture and
duct emissions from the affected storage tank to a control device that
controls an affected defumer or coking oven, or is comparable to the
control device used for controlling emissions from an affected defumer
or coking oven. If you choose to exhaust emissions from either a shape
preheater or working tank to a control device other than those used to
[[Page 42119]]
control defumer or coking oven emissions, you must satisfy for those
control devices the same monitoring requirements and operating limits
as for affected defumer and coking oven control devices.
For affected new or existing chromium refractory products kilns and
for existing clay refractory products kilns, you would have to use
natural gas, or equivalent, as the kiln fuel and document the type of
fuel used.
K. What Are the Notification, Recordkeeping, and Reporting
Requirements?
If you have an affected refractory products manufacturing source,
you would be required to submit initial notifications, notifications of
performance tests, and notifications of compliance status by the
specified dates in the proposed rule, which may vary depending on
whether the affected source is new or existing. In addition to the
information specified in 40 CFR 63.9(h)(2)(i) of the General
Provisions, you would also be required to include the following in your
Notification of Compliance Status: (1) The operating limit parameter
values established for each affected source (with supporting
documentation) and a description of the procedure used to establish the
values; (2) design information and analysis (with supporting
documentation) demonstrating conformance with requirements for capture
and collection systems; (3) your OM&M plan; (4) your SSMP; and (5)
descriptions of the methods you use to comply with any applicable work
practice standards.
You would have to submit semiannual compliance reports containing
statements and information concerning emission limitation deviations,
out of control CPMS, and periods of startup, shutdown, or malfunction
(SSM) when actions consistent with the approved SSMP were taken. If
there were no deviations from the emission limits, operating limits, or
work practice standards during the reporting period, you would only be
required to include a statement in your semiannual compliance report
that there were no deviations. If there were deviations from the
emission limits, operating limits, or work practice standards during a
reporting period, you would be required to submit the information
required in today's proposed rule in your semiannual compliance report.
If you have any SSM's during the reporting period, and you take actions
consistent with your SSMP, your compliance report would have to include
the information specified in 40 CFR 63.10(d)(5)(i). In addition, if you
undertake an action that is inconsistent with your approved SSMP, you
would then be required to submit an SSM report within 2 working days of
starting such action and within 7 working days of ending such action.
For all affected sources, you would have to maintain records for at
least 5 years from the date on which the data are recorded. You would
have to keep the records onsite for at least the first 2 years, but
could store the records offsite for the remaining 3 years. You would be
required to keep a copy of each notification and report along with
supporting documentation. You would also be required to keep records
related to the following: (1) Records of SSM; (2) records of
performance tests; (3) records used in the development of any emissions
profile; (4) records to show continuous compliance with each emission
limitation and work practice standard that applies to you; (5) records
of each operating limit deviation, including a description of the cause
of the deviation and the corrective action taken; (6) records of
production rate and organic HAP processing rate, if applicable; (7)
records for any approved alternative monitoring or test procedures; (8)
records for each CPMS; and (9) current copies of your SSMP and OM&M
plan, including any revisions, with records documenting conformance.
The records for CPMS would include records of the applicable operating
limits and monitoring data required in today's proposed rule to
demonstrate continuous compliance.
III. Rationale for Selecting the Proposed Standards
A. How Did We Select the Source Category and Any Subcategories?
Section 112(d)(1) of the CAA allows EPA to distinguish among
classes, types, and sizes of sources within a category or subcategory
in establishing emission standards. Section 112(d)(1) allows us to
define subsets of similar emission sources within a source category if
differences in emission characteristics, processes, control device use,
or opportunities for pollution prevention exist within the source
category. As a result of our analyses of data on process and emission
characteristics, we identified four subcategories of the Refractory
Products Manufacturing source category: the manufacture of refractory
products that are made using an organic HAP compound, pitch-impregnated
refractory products manufacturing, chromium refractory products
manufacturing, and clay refractory products manufacturing. We
distinguished between these subcategories because either the HAP
emissions or the affected sources differ significantly among them.
The subcategory that encompasses the production of refractories
that use organic HAP includes resin-bonded refractory curing ovens and
kilns and pitch-bonded refractory curing ovens and kilns. A few
facilities use organic HAP other than resins and pitch as binders or
additives; the shape dryers and kilns used to process refractories that
contain those binders and additives would also be included in this
subcategory. The shape dryers and curing ovens that are included in
this subcategory are similar with respect to function, operating
temperature, and processing time. Likewise, the kilns that are included
in this subcategory are similar in terms of design and operation.
Although the HAP emitted from these sources may differ, the sources all
emit organic HAP which typically are controlled using the same types of
control devices: thermal and catalytic oxidizers. For these reasons, we
concluded that there is justification to cover these thermal process
sources in a single subcategory. For the purposes of establishing MACT
floors, we classified the affected sources within this subcategory into
two groups: shape dryers and curing ovens are covered in one group, and
kilns comprise the other group of affected sources in this subcategory.
The affected sources that are included under the subcategory for
pitch-impregnated refractory production include shape preheaters,
defumers, coking ovens, and the pitch working tanks used for temporary
storage of pitch during the impregnation and defuming processes. These
sources emit organic HAP (specifically, POM) and are controlled with
thermal and catalytic oxidizers. Pitch-impregnated refractory sources
differ in design and operation from the thermal process sources used
for manufacturing resin-bonded, pitch-bonded, and other refractory
products covered by the previous subcategory. Therefore, we concluded
that a separate subcategory is warranted for pitch-impregnated
refractory sources.
The raw materials used for producing chromium refractory products
include chromium in one of two forms: chromium oxide or chromite.
Chromium oxide is a processed compound that is relatively pure and
contains chromium in the trivalent form. Chromite is naturally
occurring chromium ore and contains up to approximately 60 percent
chromium oxide. Because chromium refractory kilns emit chromium
compounds and chromium refractory products are not
[[Page 42120]]
made using organic HAP compounds, we decided to establish a separate
subcategory for chromium refractory kilns.
For clay refractory production, the primary HAP source is the kiln.
Clay refractory kilns do not differ significantly in design from the
kilns used to produce resin-bonded and pitch-bonded refractory
products. However, organic binders and additives typically are not used
in the production of clay refractories. The primary HAP emitted by clay
refractory kilns are HF and HCl. In addition, devices that are
effective in controlling HF and HCl emissions would not be used to
control organic HAP emissions. Therefore, clay refractory kilns
comprise a separate subcategory under the proposed rule for refractory
products manufacturing.
Several refractory products plants produce nonclay refractories
that do not contain organic HAP. For these plants, and plants that
produce only monolithics, HAP emissions consist of small amounts of HAP
metals that are released from raw material processing operations. These
facilities are all area sources that emit much less than 10 tons/yr of
any single HAP and 25 tons/yr of total HAP, and the HAP sources at
these plants generally are well controlled. Because the Refractory
Products Manufacturing source category was listed for major sources and
not for area sources, we decided against including these facilities
within the scope of the proposed rule.
We considered regulating sources of fine mineral fibers associated
with the production of RCF. However, we determined that none of the
existing RCF manufacturing facilities are major sources, and it is
unlikely that any new sources would be constructed that would be major
sources of HAP. The RCF industry is not expected to grow significantly,
and, if new sources were constructed, they most likely would be well
controlled because it would not be economical to allow RCF product to
be emitted in any significant quantities.
We also considered regulating fused-cast refractory products
manufacturing sources. However, we decided against regulating these
facilities. There are only two fused-cast refractory facilities
currently operating, and both are well controlled. Emissions of HAP
from these facilities are much less than 10 tons/yr for any single HAP
and 25 tons/yr of total HAP, and no new facilities or growth is
expected in this sector of the refractories industry.
B. How Did We Select the Emission Sources To Be Regulated?
The primary sources of HAP emissions at most refractory products
manufacturing plants are the thermal process units. Thermal process
units emit the organic constituents of the raw materials, binders, and
additives that comprise refractory product formulations. Several of the
organic constituents of binders and additives used in the refractory
industry are HAP. Many resins contain phenol and formaldehyde, and some
resins also contain methanol and ethylene glycol. The available test
data for resin-bonded refractory sources indicate that approximately 15
percent of the free phenol, 40 percent of the formaldehyde, 100 percent
of the methanol, and 14 percent of the ethylene glycol contained in the
resin are emitted from thermal process sources. Based on these
percentages, we estimate that several existing facilities that use
organic binders and additives to produce refractory products are
potential major sources for at least one of these organic HAP. For this
reason, we decided that regulation of organic HAP from existing and new
shape dryers, curing ovens, and kilns is warranted.
Coal tar and petroleum pitch used in the production of pitch-bonded
and pitch-impregnated refractory products consist of POM. The available
emission data on pitch-impregnated refractory production indicate that
40 to 45 percent of the pitch is volatilized and emitted from thermal
process units. Based on these data, several facilities that produce
pitch-impregnated or pitch-bonded refractory products are potential
major sources of POM emissions. For this reason, we decided that it is
necessary to regulate existing and new pitch-bonded and pitch-
impregnated refractory products thermal process units, the sources of
POM emissions.
The source category Chromium Refractories Production was included
on the initial source category list based on an Agency screening study
conducted in 1985. As part of that study, tests were performed on a
chromium refractory kiln. At the temperature encountered in the kiln
(1540 deg.C (2800 deg.F)), hexavalent chromium, which is a known human
carcinogen, was formed and emitted to the atmosphere as PM. The 1985
study recommended that fabric filters (baghouses) be installed on kilns
used to fire chromium refractories to capture the PM emissions from the
kiln outlets at the ten plants that produced chromium refractories at
that time. Currently, one major source in the refractory products
source category produces chromium refractory products.
At the temperatures encountered in clay refractory kilns, naturally
occurring fluorides and chlorides found in raw clays are released to
the atmosphere as HF and HCl. We estimate that some existing clay
refractory manufacturing facilities are major sources due to HF
emissions from their kilns, and at least one of those facilities could
also be a major source of HCl due to kiln emissions. Because kilns are
the only clay refractory products sources that emit HF and HCl and are
located at major source facilities, we decided to limit the scope of
the proposed rule to kilns for the clay refractory products
subcategory.
C. How Did We Define the Affected Sources?
Affected source means the collection of equipment and processes in
the source category or subcategory to which the emission limitations
and other regulatory requirements apply. The affected source may be the
same collection of equipment and processes as the source category or it
may be a subset of the source category. For each rule, we must decide
which individual pieces of equipment and processes warrant separate
standards in the context of the CAA section 112 requirements and the
industry operating practices.
Most refractory products manufacturing facilities are characterized
by numerous diverse and complex operations. Many of the process units
at typical refractories plants are not sources of HAP emissions. For
this reason, rather than define the affected sources as the plants
themselves, we decided to define the affected sources in terms of the
specific process units that emit HAP and are associated with the
production of specific types of refractory products. These product
types include resin-bonded, pitch-bonded, and other refractory products
that use organic HAP; pitch-impregnated refractory products; chromium
refractory products; and clay refractory products. The affected
sources, which are listed in Table 2 of this preamble, include shape
dryers and curing ovens, kilns, shape preheaters, pitch working tanks,
defumers, and coking ovens.
[[Page 42121]]
D. How Did We Determine the Proposed Standards for Existing Sources?
1. How Did We Determine the MACT Floor for Existing Sources?
Section 112(d)(3) of the CAA specifies that each MACT standard be
at least as stringent as the floor for the sources in the relevant
source category or subcategory. It further specifies that we set
standards for existing sources that are no less stringent than the
average emission limitation achieved by the best-performing 12 percent
of existing sources (for which the Administrator has emissions
information) where there are 30 or more sources in the category or
subcategory. For source categories with less than 30 sources, the CAA
requires that the floor be based on the average emission limitation
achieved by the best-performing five sources. Our interpretation of the
``average emission limitation'' is that it is a measure of central
tendency, such as the arithmetic average or the mean. If the median is
used when there are at least 30 sources, then the emission level
achievable by the source and its control device that is at the bottom
of the top 6 percent of the best-performing sources (i.e., the 94th
percentile) represents the MACT floor control level. For source
categories or subcategories with less than 30 sources, we interpret the
MACT floor level to correspond to the median of the best-performing
five sources. Finally, in determining the pool of sources from which
the floors are determined, we consider only those facilities that are
major HAP sources or synthetic area HAP sources (i.e., those that would
be major HAP sources in the absence of any emission controls currently
in place). The MACT floors for each subcategory identified during
development of the proposed rule are based on these interpretations.
The affected existing thermal process units that emit organic HAP
include shape dryers, curing ovens, kilns, coking ovens, defumers,
shape preheaters, and pitch working tanks. To rank these sources in
terms of their performance in controlling organic HAP emissions, we
needed uncontrolled and controlled emissions data for each source type.
Because of the limited emissions data available for organic HAP
sources, it is not possible to rank the sources based on actual
emissions reductions. An alternative approach to using actual emissions
data is to rank sources based on the likely performance level of the
control devices in place. The MACT floor technology can then be
selected as the control device(s) matching the 94th percentile unit, or
for subcategories with less than 30 sources, the median of the best-
performing five sources. We used this approach to determine the MACT
floors for organic HAP emissions from thermal process units.
Among the refractory products thermal process sources that are
currently controlled for organic emissions, the majority are controlled
with thermal oxidizers. The other controlled sources are equipped with
catalytic oxidizers. Thermal oxidizer performance levels are largely a
function of three parameters: combustion chamber temperature, residence
time of the gases in the combustion chamber, and the degree of mixing
of the gases in the combustion chamber. Therefore, performance level
rankings should take these parameters into consideration. Based on the
available design and operating data, we were unable to evaluate the
subject thermal oxidizers in terms of their degree of mixing.
Therefore, we based our rankings of thermal oxidizers on combustion
chamber temperature and residence time only, using the Arrhenius
equation, which relates the amount of an organic compound remaining
after combustion for a specific period of time at a specified
temperature.
We were not able to compare quantitatively the performance of
catalytic oxidizers to that of thermal oxidizers. The Arrhenius
equation does not apply to catalytic oxidizers and we were not able to
identify a comparable method for evaluating catalytic oxidizer
performance based on design. Catalytic oxidizer performance is largely
a function of the space velocity and the temperatures at the inlet and
outlet of the catalyst bed. Space velocity is the reciprocal of the
residence time in the catalyst bed and is defined as the flow rate of
the gas entering the catalyst bed divided by the volume of the catalyst
bed. For the catalytic oxidizers currently in operation at refractory
products manufacturing plants, we were able to obtain data on catalyst
bed inlet and outlet temperatures, but could not obtain space velocity
data. For these reasons, our ranking of catalytic oxidizers for today's
proposed rule is largely qualitative.
Before ranking sources according to control technology, we also
differentiated between the various types of thermal process sources
that would be affected by today's proposed rule. We grouped shape
dryers and curing ovens because they are similar in terms of function,
design, and operating parameters. The initial thermal processing step
in the production of refractory shapes is drying or curing. Shape
dryers and curing ovens, which are used to form temporary bonds between
refractory body material grains, typically operate between 90 deg. and
260 deg.C (200 deg. and 500 deg.F). Although there are large variations
among plants, cycle times for shape dryers and curing ovens generally
are in the range of 5 to 20 hours. Based on the data submitted to us in
1998 in response to our information collection requests sent to
refractory products manufacturers, there are a total of 35 shape dryers
and curing ovens that are used to produce resin-bonded, pitch-bonded,
or other refractory products that use organic HAP; and are located at
facilities that are major or synthetic area sources of organic HAP.
Emissions from 21 of the shape dryers and curing ovens are controlled:
16 are controlled with thermal oxidizers, and 5 are controlled with
catalytic oxidizers. The median of the best-performing 12 percent of
these sources (i.e., the 94th percentile) is controlled with a thermal
oxidizer that is designed for a 0.64-second residence time at 815 deg.C
(1500 deg.F). Therefore, this control device represents the MACT floor
for existing shape dryers and curing ovens.
Data from the wood products industry indicate that the performance
of catalytic oxidizers with catalyst bed outlet temperatures of
430 deg. to 480 deg.C (800 deg. to 900 deg.F) is comparable to the
performance of thermal oxidizers designed for a residence time of
approximately 0.5 seconds and combustion chamber temperatures of
820 deg. to 870 deg.C (1500 deg. to 1600 deg.F). Two of the five
catalytic oxidizers used in the refractory products industry to control
curing oven emissions operate with catalyst bed outlet temperatures of
approximately 450 deg.C (850 deg.). Therefore, we concluded that these
two controls are comparable to the MACT floor control level for shape
dryers and curing ovens. We concluded that the other three catalytic
oxidizers, which operate with bed outlet temperatures of approximately
370 deg.C (700 deg.F), are much less effective in controlling organic
emissions than the MACT floor level of control for this group of
sources.
Following the drying or curing, refractory shapes typically are
fired in kilns, which operate at peak temperatures in the range of
1090 deg. to 1540 deg.C (2000 deg. to 2800 deg.F). We estimated that
there are 26 kilns that are used to produce resin-bonded, pitch-bonded,
or other refractory products that contain organic HAP and are located
at facilities that are major or synthetic area sources of organic HAP.
Nine of these kilns are controlled, all with thermal oxidizers. Because
there are less than 30 sources in this group, the MACT floor for this
[[Page 42122]]
group of sources corresponds to the median of the best-performing five
sources, which is a kiln controlled with a thermal oxidizer designed
for a 0.41-second residence time at 760 deg.C (1400 deg.F).
In the pitch-impregnated refractory process, fired refractory
shapes initially are heated in a shape preheater, which typically
operates at temperatures of 150 deg. to 260 deg.C (300 deg. to
500 deg.F). Of the seven shape preheaters located at four pitch-
impregnated refractory manufacturing facilities that are major or
synthetic area sources of organic HAP, two are controlled with thermal
oxidizers and the other five are not equipped with add-on controls. All
four of the facilities periodically clean the deposits of pitch on the
holding baskets or containers by abrasive blasting. Cleaning is done on
an as-needed basis, but a typical cleaning frequency is once every ten
cycles. Of the two controlled preheaters, both are ducted to the
thermal oxidizers that are used to control defumer emissions. The MACT
floor for this group of sources is based on the median of the best-
performing five sources, which corresponds to periodic basket/container
cleaning (i.e., every ten cycles).
As the shapes are heated in the shape preheater, pitch is
transferred to a pitch working tank, which heats the pitch to between
150 deg. and 260 deg.C (300 deg. and 500 deg.F) prior to the pitch
being transferred to the autoclave. There are a total of four pitch
working tanks that are located at facilities that produce pitch-
impregnated refractories and are major or synthetic area sources of
organic HAP. One of these working tanks is uncontrolled. The other
three pitch working tanks are ducted to thermal oxidizers that are used
to control defumer emissions. The thermal oxidizers operate only during
the impregnation-defuming process. As a result, the oxidizers provide
periodic, rather than continuous, control of working tank emissions.
Because there are less than 30 existing sources in this group, the MACT
floor control for existing pitch working tanks is based on the median
of the best-controlled five sources, which corresponds to periodic
control of tank emissions by means of a thermal oxidizer.
After the shapes are impregnated with pitch, they are defumed.
Defuming takes place either in the autoclave or in a separate defumer.
If the defuming step occurs in the autoclave, the autoclave serves as
the defumer. There are five defumers located at facilities that are
major or synthetic area sources of organic HAP; four are controlled
with thermal oxidizers, and one is controlled with a catalytic
oxidizer. The MACT floor for these sources corresponds to the median of
the best-performing five sources, which a defumer controlled with a
thermal oxidizer that is designed for a 0.52-second residence time at
790 deg.C (1450 deg.F). Based on the data from the wood products
industry, which was discussed previously in this preamble, we concluded
that the catalytic unit, which is designed for a catalyst bed outlet
temperature 450 deg.C (845 deg.F) would be comparable to the floor
level of control for existing defumers.
After defuming, the impregnated shapes may undergo an additional
process referred to as coking. In the coking process, the shapes are
placed in a coking oven and heated to between 540 deg. and 870 deg.C
(1000 deg. and 1600 deg.F) under reducing conditions to drive off the
volatile constituents (i.e., POM) of the pitch. Our data indicate that
there are six coking ovens located at facilities that are major or
synthetic area sources of organic HAP. All six of the coking ovens are
controlled with thermal oxidizers. Because there are less than 30
existing sources, the MACT floor for these sources corresponds to the
median of the best-performing five sources, which is a coking oven
controlled with a thermal oxidizer that is designed for a 1.0-second
residence time at 915 deg.C (1680 deg.F).
The HAP emitted from chromium refractory products kilns include
hexavalent chromium, other chromium compounds, and other nonvolatile
HAP metals. Because these HAP are emitted in the form of PM, we
considered establishing an emission standard in the format of a PM
emission limit. However, none of the 32 chromium refractory products
kilns currently in operation are equipped with add-on APCD that have
been demonstrated to reduce HAP metal emissions that occur in the
particulate form. Hence, considering only add-on APCD, the MACT floor,
as defined in section 112 of the Clean Air Act, for existing chromium
refractory kilns would not reduce emissions of chromium or other
nonvolatile HAP metals.
In addition to add-on APCD, we considered other possible MACT
floors for existing chromium refractory products kilns, such as the use
of low-HAP raw materials or fuels, that would reduce emissions of
chromium or other nonvolatile HAP metals.
Emissions of chromium and other nonvolatile HAP metals from kilns
can originate with the raw materials and the kiln fuel. Consequently,
we considered nonchromium raw materials as a potential MACT floor for
chromium refractory kilns. Chromium greatly enhances the ability of
refractory linings to withstand high temperatures and corrosive
environments; where those conditions exist, there is no reliable raw
material substitute for chromium. Therefore, we concluded that there
are no substitutes for chromium oxide or chromite in chromium
refractory products, and raw material substitution is not a feasible
component of the MACT floor for existing chromium refractory products
kilns.
We considered the use of low-HAP fuels as the basis for a MACT
floor standard for existing chromium refractory products kilns. With
the exception of natural gas, the fuels that are commonly used to fire
industrial kilns and furnaces (e.g., fuel oil and coal) contain HAP
metals, which are subsequently emitted when those fuels are burned.
Because fuels can contribute to emissions of chromium and other HAP
metals from kilns, a MACT floor for existing chromium refractory
products kilns could be based on fuel type. Although a few area source
refractory manufacturing plants use fuel oil in kilns, our data
indicate that all of the six facilities that produce fired chromium
refractories, including the one major source in our source category
that produces chromium refractory products, use natural gas to fuel the
kilns that fire chromium refractories. Because natural gas does not
contain HAP metals and, therefore, does not contribute to HAP metal
emissions, the use of natural gas or other equivalent clean fuel is a
feasible MACT floor for existing chromium refractory products kilns.
Having eliminated add-on APCD and raw material substitution as options
for a MACT floor for this subcategory, we concluded that the use of
natural gas or other such clean fuel is the MACT floor for existing
chromium refractory kilns. Under an emission limitation (in this case,
a work practice standard) based on this floor, you would not be
permitted to fire existing chromium refractory products kilns with
coal, fuel oil, waste oil, or other fuels that contain HAP metals.
For clay refractory products kilns, the HAP to be regulated are HF
and HCl. There are a total of 100 clay refractory products kilns, six
of which are located at facilities that are major or synthetic area
sources. However, none of these clay refractory kilns are equipped with
add-on APCD that have been demonstrated to reduce emissions of HF or
HCl. Therefore, considering only add-on APCD, the MACT floor for
existing clay refractory kilns would not reduce emissions of HF or HCl.
In addition to add-on APCD, we considered other possible MACT floors
for existing clay
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refractory products kilns, such as the use of low-HAP raw materials or
fuels, that would reduce emissions of HF or HCl. Because HF and HCl
emissions from clay refractory kilns are largely a function of the
primary raw material (i.e., fire clay), we considered raw material
substitution with fire clays that have low concentrations of fluorides
and chlorides as a possible floor for existing clay refractory kilns.
The available data indicate that the fluoride and chloride contents of
many clays can vary significantly, even within the same deposit. There
are no available data that indicate that any of the fire clay deposits
that are used by major and synthetic area source facilities are
uniformly low in fluorides and chlorides. Furthermore, the procurement
of low-fluoride or low-chloride clays as a measure for controlling
emissions is not practiced in the refractory products industry.
We also considered pre-calcined clay as a possible floor for clay
refractory kilns. Calcining of fire clay prior to incorporating the
clay into a refractory shape drives off the HF and HCl that otherwise
would be emitted from a kiln when firing clay refractory products.
However, none of the 25 facilities that produce fired clay refractories
currently use pre-calcined clay for clay refractory production as a
means of reducing emissions of HF or HCl. Therefore, substitution of
raw clay with calcined clay cannot be considered the MACT floor
technology for existing clay refractory products manufacturers.
Therefore, we concluded that raw material substitution is not a
feasible MACT floor for existing clay refractory products kilns.
We also considered the use of low-HAP fuels as the basis for a MACT
floor standard for existing clay refractory products kilns. Certain
fuels, waste-derived fuels in particular, may contribute to emissions
of HF or HCl when burned. In addition, the fuels that are commonly used
to fire some industrial kilns and furnaces (e.g., fuel oil and coal)
contain HAP metals, which are subsequently emitted when those fuels are
burned. Because fuels can contribute to HAP emissions from kilns, a
MACT floor for existing clay refractory products kilns could be based
on fuel type. Although a few area source facilities use fuel oil to
fire their refractory kilns, our data indicate that all clay refractory
products manufacturers use natural gas to fuel the kilns that fire clay
refractories. Because natural gas does not contribute to emissions of
HF, HCl, or HAP metals, the use of natural gas, or other equivalent
clean fuel, is a feasible MACT floor for existing clay refractory
products kilns. Having eliminated add-on APCD and raw material
substitution as options for a MACT floor for this subcategory, we
concluded that the use of natural gas or other such clean fuel is the
MACT floor for existing clay refractory kilns. An emission limitation
(in this case, a work practice standard) based on this floor would
prohibit the use of coal, fuel oil, waste oil, or equivalent fuels to
fire existing clay refractory products kilns.
2. How Did We Select the Emission Limits for Existing Sources?
Section 112(d)(3) of the CAA specifies that each MACT standard be
at least as stringent as the floor for the sources in the relevant
source category or subcategory. Consequently, the MACT floor represents
the minimum level of control that can be used in establishing emission
limits for existing sources subject to NESHAP. After identifying the
emission limits that correspond to the MACT floors for existing
sources, we consider regulatory alternatives that are more stringent
than the MACT floor levels. Regulatory alternatives are emission
control options, process changes, and other methods for reducing HAP
emissions other than those defined by the MACT floor. The selected
regulatory alternative may be more stringent than the MACT floor, but
the control level must be achievable and reasonable in the
Administrator's judgement considering cost, non-air quality health and
environmental impacts, and energy requirements. The objective in
considering these beyond-the-floor control options is to achieve the
maximum degree of emissions reductions without imposing unreasonable
impacts (section 112(d)(2)of the CAA).
Today's proposed rule would establish emission limits for organic
HAP emitted from affected existing thermal process sources. These
emission limits would apply to the following affected sources: shape
dryers, curing ovens and kilns used to produce refractory products that
contain organic HAP, and pitch-impregnated refractory products defumers
and coking ovens. The emission limits would be presented in two
alternate formats: a THC emission concentration and combustion
efficiency of certain types of add-on control devices.
Today's proposed rule would establish a THC emission limit as a
surrogate for organic HAP emitted from affected thermal process
sources. Affected thermal process sources include shape dryers, curing
ovens, and kilns that are used to produce resin-bonded or pitch-bonded
refractory products; coking ovens and defumers that are used to produce
pitch-impregnated refractory products; and other shape dryers and kilns
that process refractory shapes that use organic HAP that is emitted
during the drying or firing processes.
To determine an appropriate THC concentration limit for refractory
products thermal process sources that are controlled at the MACT floor
level, we reviewed the available emission test data for the refractory
products manufacturing industry. Although we have no THC data on
sources controlled at the MACT floor control levels, we have data on
two sources with thermal oxidizers that we estimate are more effective
in controlling organic emissions than the MACT floor level, and four
sources with thermal oxidizers that we estimate are less effective in
controlling organic emissions than the MACT floor level. Both of the
sources with controls that are more effective than the MACT floor level
easily achieved THC emission concentrations of less than 20 ppmvd,
corrected to 18 percent O2. In addition, one of the four
sources with controls that are less effective than the floor level
achieved a THC emission concentration of less than 20 ppmvd. The THC
emission concentrations for the remaining three sources were at least
30 ppmvd. Based on these data, we concluded that a THC emission limit
of 20 ppmvd is appropriate and representative of the emission level
that the MACT floor controls can achieve. This emission limit also is
consistent with other NESHAP and new source performance standards
(NSPS) for industries that commonly use thermal or catalytic oxidizers
for control of organic HAP emissions. Examples include 40 CFR part 60,
subparts DDD, III, and NNN; and 40 CFR part 63, subparts DD, YY, GGG,
HHH, JJJ, MMM, and PPP.
We reviewed the available emission test data to determine if it
were possible to establish a THC emission concentration limit that
would be more stringent than the MACT floor for existing shape dryers,
curing ovens, kilns, defumers, and coking ovens. However, the available
data indicate that there are no other control devices in use that would
perform better than the MACT floor level thermal oxidizers for these
sources. We also considered establishing an emission limit based on the
estimated level of control that would be achieved by thermal oxidizers
that operate at higher temperatures and/or longer residence time than
do the MACT floor level thermal oxidizers. However, we concluded that
the
[[Page 42124]]
available data do not show that these thermal oxidizers would achieve
better control of organic HAP than do the MACT floor level thermal
oxidizers. Therefore, we decided against establishing a THC emission
concentration limit that was more stringent than the MACT floor level
of control for existing shape dryers, curing ovens, kilns, defumers,
and coking ovens.
Combustion efficiency of a thermal oxidizer is a function of the
concentrations of CO2, CO, and THC in the exhaust stream of
the oxidizer. To establish a combustion efficiency standard for thermal
process sources, we reviewed the available data for CO2, CO,
and THC emissions from sources controlled with thermal oxidizers that
are comparable to the MACT floor technology. In addition to data from
refractory products thermal process sources, data from another industry
(asphalt roofing) were used to supplement the refractory products data.
We believe that using data on asphalt roofing sources is valid because
the exhaust stream characteristics and emission controls for the
asphalt roofing sources are similar to those found in the refractory
products industry.
The data on CO2 emissions indicate that exhaust gas
concentrations of CO2, corrected to 18 percent
O2, for refractory products sources that are controlled to
the MACT floor level typically are between 1.7 and 2.0 percent. The
data on CO emissions indicate that thermal oxidizer outlet
concentrations of 10 to 20 ppmvd are representative of CO
concentrations from sources in the refractory products manufacturing
industry with MACT floor level controls. The data on THC emissions
indicate that thermal oxidizer outlet concentrations of 10 to 20 ppmvd
are representative of THC concentrations from sources in the refractory
products manufacturing industry with MACT floor level controls.
Using the value of 1.7 percent CO2, and the midpoint
values for 10 to 20 ppmvd CO and 10 to 20 ppmvd THC, we calculated the
combustion efficiency to be 99.8 percent. On this basis, we believe
that a combustion efficiency limit of 99.8 percent is achievable for
refractory products thermal process sources that operate combustion-
based controls that are comparable to the MACT floor level of control.
Our analysis of the available data indicates that a combustion
efficiency of 99.8 percent is currently achieved by thermal process
sources in the refractory products industry that are controlled to the
level of the MACT floor. Data from asphalt roofing industry also
demonstrate that sources with emission controls comparable to the MACT
floor controls for the refractory products industry achieve a 99.8
percent combustion efficiency. With a combustion efficiency limit,
affected sources in the refractory products industry that are
controlled with thermal oxidizers that operate below the floor level of
control would have the option of increasing thermal oxidizer operating
temperature in order to reduce CO and THC emissions, and thus increase
the combustion efficiency and avoid having to install new emission
controls.
A combustion efficiency limit of 99.8 percent may not be an
appropriate indicator of the floor level of organic emission control
for some sources because combustion efficiency is largely a function of
the CO2 concentration, and CO2 concentrations in
thermal oxidizer exhaust streams vary from source to source. These
variations can be attributed to differences in process operation, the
amounts of CO2 entering the thermal oxidizer from the
process exhaust stream, and the degree of combustion within the thermal
oxidizer. As the CO2 concentration increases, the
concentrations of CO and THC that correspond to a specified combustion
efficiency limit also increase. For example, at 2.0 percent
CO2, the sum of the THC and CO concentrations can be no more
than 40 ppmvd to achieve a combustion efficiency of 99.8 percent.
However, at 4.0 percent CO2, the source would meet 99.8
percent combustion efficiency even if the sum of the THC and CO
concentrations were 80 ppmvd. For this reason, we concluded that it was
necessary to restrict the use of the combustion efficiency limit for
sources with relatively high CO2 concentrations. To ensure
that owners and operators of affected sources who choose to comply with
this combustion efficiency limit are achieving good control, we decided
to establish an upper limit of 3.0 percent CO2 for affected
thermal process sources. In other words, demonstrating compliance with
the combustion efficiency limit is an option only for sources that have
exhaust gas CO2 concentrations equal to or less than 3.0
percent (corrected to 18 percent O2) at the outlet of the
control device (thermal or catalytic oxidizer). At 3.0 percent
CO2, the combined concentrations of CO and THC can be as
high as 60 ppmvd to achieve a combustion efficiency of 99.8 percent.
As CO2 concentrations decrease, it becomes increasingly
difficult to meet a specified combustion efficiency. For example, at
1.0 percent CO2, the sum of the THC and CO concentrations
can be no greater than 20 ppmvd to meet a combustion efficiency of 99.8
percent. From the perspective of organic HAP emissions control, low
CO2 concentrations do not present a problem because the
lower the concentration of CO2, the higher the con |
