United States
Environmental Protection
Agency
Office of Air Quality
Planning and Standards
Research Triangle Park NC 27711
November 1980
Air
Revised Standards for Draft
Basic Oxygen Process EIS
Furnaces —
Background Information
for Proposed Standards
Preliminary Draft
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NOTICE
This document has not been formally released by EPA and should not now be construed to represent
Agency policy. It is being circulated for comment on its technical accuracy and policy implications.
Revised Standards for Basic
Oxygen Process Furnaces —
Background Information
for Proposed Standards
Emission Standards and Engineering Division
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air, Noise, and Radiation
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
November 1980
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TABLE OF CONTENTS
Page
Tables vi
Figures viii
2. INTRODUCTION 2-1
2.1 BACKGROUND AND AUTHORITY FOR STANDARDS 2-1
2.2 SELECTION OF CATEGORIES AND STATIONARY SOURCES 2-4
2.3 PROCEDURE FOR DEVELOPMENT OF STANDARDS OF PERFORMANCE ... 2-6
2.4 CONSIDERATION OF COSTS 2-8
2.5 CONSIDERATION OF ENVIRONMENTAL IMPACTS 2-9
2.6 IMPACT ON EXISTING SOURCES 2-10
2.7 REVISION OF STANDARDS OF PERFORMANCE 2-11
3. BASIC OXYGEN PROCESS STEELMAKING INDUSTRY 3-1
3.1 GENERAL 3-1
3.2 PROCESS FACILITIES AND THEIR EMISSIONS 3-5
3.2.1 Basic Oxygen Process Furnaces and Their Operation. . 3-5
3.2.1.1 Material Flow 3-9
3.2.1.2 Material Balance 3-14
3.2.1.3 Methods of Operation 3-16
3.2.2 Process Emissions 3-19
3.2.2.1 Fugitive Emission Sources 3-20
3.2.2.2 Nonprocess Sources of Fugitive Emissions. . . 3-22
3.2.3 Process Emissions Characterization 3-23
3.2.3.1 Emissions Generated During the Oxygen Blow. . 3^23
3.2.3.2 Emissions from Secondary Sources 3-25
3.3 REFERENCES 3-29
4. EMISSION CONTROL TECHNIQUES 4-1
4.1 INTRODUCTION 4-1
4.2 CAPTURE OF SECONDARY EMISSIONS FROM FURNACE OPERATIONS
(CHARGING, SAMPLING, TAPPING) 4-2
4.2.1 Furnace Enclosures 4-2
4.2,1.1 Kaiser Steel (Closed Hood, Top Blown) .... 4-7
4.2.1.2 Republic Steel - Chicago (Closed Hood,
Bottom Blown) 4-9
4.2.1.3 Republic Steel, Cleveland, Ohio 4-16
4.2.2 Local Hoods 4-20
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Page
4.2.3 Canopy or Roof Hoods, Partial Building Evacuation. . 4-21
4.2.3.1 Inland Steel, East Chicago, Indiana (Closed
Hood, Top Blown) 4~22
4.2.4 Building Evacuation 4-26
4.2.5 Other Systems 4~27
4.2.5.1 Bethlehem Steel, Bethlehem, Pennsylvania. . - 4-29
4.2.5.2 Republic Steel, Gadsden, Alabama 4'33
4.2.5.3 Foreign Installations 4~38
4.3 CONTROL OF SECONDARY EMISSIONS FROM ANCILLARY OPERATIONS
(HOT METAL TRANSFER AND SKIMMING) 4'40
4.3.1 Kaiser Steel, Fontana California 4"40
4.4 PARTICULATE CONTROL DEVICES 4~42
4.4.1 The Fabric Filter 4~42
4.4.2 Wet Scrubbers 4-46
4.4.3 The Electrostatic Precipitator 4-47
4.5 REFERENCES 4-50
5. MODIFICATION AND RECONSTRUCTION 5-1
5.1 SUMMARY OF 40 CFR 60 PROVISIONS FOR MODIFICATIONS AND
RECONSTRUCTIONS 5-1
5.1.1 Modification 5-1
5.1.2 Reconstruction 5-2
5.2 APPLICABILITY OF BOPF FACILITIES 5-3
5.2.1 Potential Modification 5-3
5.2.1.1 Increasing furnace capacity 5-3
5.2.1.2 KMS system conversion 5-3
5.2.1.3 Addition of scrap preheat capability 5-4
5.2.1.4 Applicability of emission control techniques. 5-4
5.2.2 Reconstruction 5-4
5.3 REFERENCES 5-5
6. MODEL PLANTS AND REGULATORY ALTERNATIVES 6-1
6.1 MODEL PLANTS 6-1
6.1.1 Model Plant Selection 6-1
6.1.2 Fugitive Emission Sources 6-4
6.2 REGULATORY ALTERNATIVES 6-6
6.2.1 Regulatory Alternative Overview 6-6
6.2.2 Regulatory Alternative I 6-7
6.2.3 Regulatory Alternative II 6-7
6.2.3.1 Greenfield facilities 6-7
6.2.3.2 Third vessel addition to an existing two
vessel shops 6-8
6.2.3.3 Conversion of existing vessels to the KMS
system 6-8
6.2.4 Regulatory Alternative III 6-9
6.2.5 Gas Cleaning System 6-9
6.3 REFERENCES 6-9
IV
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7. ENVIRONMENTAL IMPACT 7-1
7-1 AIR POLLUTION IMPACT 7-1
7.2 WATER POLLUTION IMPACT 7-3
7.3 SOLID WASTE IMPACT 7-9
7.4 ENERGY IMPACT 7-9
7.5 OTHER ENVIRONMENTAL IMPACTS 7-12
7.6 OTHER ENVIRONMENTAL CONCERNS 7-12
7.7 REFERENCES 7-12
8. COSTS 8-1
8.1 COST ANALYSIS OF REGULATORY ALTERNATIVES 8-1
8.1.1 New Facilities 8-1
8.1.2 Modified/Reconstructed Facilities 8-17
8.2 OTHER COST CONSIDERATIONS 8-17
8.3 REFERENCES 8-17
APPENDIX A EVOLUTION OF THE PROPOSED STANDARDS A-l
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TABLES
Number
3-1 BOPF Locations and Design Capacities .......... 3-3
3-2 Typical Particle-size Distribution of Open Hood, Top
Blown BOPF Blowing Emissions .............. 3-24
3-3 Particle-size Distribution of Closed Hood, Top Blown
BOPF Blowing Emissions ................. 3-24
3-4 Comparison of Parti cul ate Composition from Open and
Closed Hood Collection Systems ............. 3-24
3-5 Uncontrolled Emission Factors for BOPF Secondary
Emissions ........................ 3-26
3-6 Particle Size Distribution for Q-BOPF Charging
Emissions ........................ 3-27
3-7 Composition of Fugitive Emissions from BOPFs ...... 3-28
4-1 Kaiser Steel, Fontana, California ............ 4-10
4-2 Kaiser Steel Test — Number of Times Opacities Equal to or
Greater Than Twenty Percent were Observed ........ 4-11
4-3 Republic Steel, Chicago, Illinois ............ 4-14
4-4 Republic Steel Q-BOP Test—Number of Times Opacities
Equal to or Greater Than Twenty Percent Were Observed. . 4-15
4-5 Republic Steel Corporation, Cleveland, Ohio ....... 4-18
4-6 Republic Steel Test (Cleveland)--Number of Times
Opacities Equal to or Greater Than Twenty Percent Were
Observed ........................ 4-19
4-7 Inland Steel, East Chicago, Indiana ........... 4-24
4-8 Inland Steel Test — Number of Times Opacities Equal to
or Greater Than Twenty Percent Were Observed ...... 4-25
4-9 Bethlehem Steel, Bethlehem, Pennsylvania ........ 4-31
4-10 Bethlehem Steel, Bethlehem, Pennsylvania — Number of
Times Opacities Equal to or Greater Than Twenty Percent
Were Observed ...................... 4-32
4-11 Republic Steel, Gadsden, Alabama ............ 4-36
4-12 . Republic Steel Test (Gadsden) — Number of Times
Opacities Equal to or Greater Than Twenty Percent Were
Observed ........................ 4-37
4-13 Inland Steel, East Chicago, Indiana Secondary Emission
Control System Performance Test Results ......... 4-48
6-1 Model Plants 6-2
6-2 Emission Table for BOPF Model Plants 6-5
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Number Page
7-1 U.S. BOPF Steelmaking Capacity 7-1
7-11 Power Plant Energy Requirements and Particulate
Emissions Attributable to BOPF Secondary Emission
Control. 7-4
7-12 Potential Nationwide Reduction in Particulate
Emissions from Secondary Emission Control 7-5
7-13 Uncontrolled Inorganic Emissions from Hot Metal
Addition to a Q-BOPF 7-6
7-14 Results of Aqueous Solubility Tests of BOPF Emission
Control System Dusts 7-8
7-15 Expected Energy Increase for Secondary Emission
Control Systems, 1981-1986 7-10
7-16 Summary of Environmental Impacts—BOPF Secondary
Emissions 7-11
8-1 Capital Costs of Control By Furnace Enclosure—BOPF
Secondary Emissions—Millions of Dollars (July 1980) . . 8-2
8-2 Annual Costs of Control By Furnace Enclosure—BOPF
Secondary Emissions--Millions of Dollars (July 1980) . . 8-5
8-3 Capital Cost of Control By Building Evacuation—BOPF
Secondary Emissions—Millions of Dollars (July 1980) . . 8-7
8-4 Annual Costs of Control By Building Evacuation—BOPF
Secondary Emissions—Millions of Dollars (July 1980) . . 8-8
8-5 BOPF Shop Annual Operating Costs (106 July 1980
Dollars/Yr). 8-9
8-6 Design Criteria for Model Plant Secondary Emission
Controls Systems . 8-10
8-7 Cost Relationship for BOPF Secondary Emission Control. . 8-11
8-8 Cost Effectiveness of Secondary Emission Control .... 8-13
8-9 Cost Estimate for OSHA Compliance—BOPF Secondary
Emissions—Millions of Dollar (July 1980) 8-14
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FIGURES
Number
3-1 Schematic flow chart for integrated and nonintegrated
steelmaking 3-2
3-2 Geographic distribution of the U.S. iron and steel BOPF
steel making facilities 3-4
3-3 The steps for making steel by the Basic Oxygen Process . 3-7
3-4 Time sequence of top blown BOPF operations 3-8
3-5 BOPF schematic elevation of a two furnace facility ... 3-10
3-6 BOPF schematic cross-section of operating units 3-11
3-7 Flow diagram for Basic Oxygen Process furnace
operations 3-12
4-1 BOP furnace enclosure 4-3
4-2 Furnace enclosure for a Q-BOPF 4-4
4-3 Schematic of Kaiser Steel — Fontana Basic Oxygen
secondary emission control system 4-8
4-4 Republic Steel Corporation's Q-BOP emission control
system 4-12
4-5 Republic Steel Corporation, Cleveland, Ohio, BOPF
secondary emission control system schematic 4-17
4-6 Bethlehem Steel, Bethlehem, Pennsylvania—BOPF partial
furnace enclosure for open primary hood 4-30
4-7 Gaw damper position during hot metal charging at
RCS/Gadsden 4-34
4-8 Tapping emission control at RCS/Gadsden 4-35
4-9 Kawasaki-Chiba Works plant arrangement with partial
building evacuation 4-39
4-10 Kaiser Steel hot metal transfer and skimming station . . 4-41
4-11 Fabric filter outlet concentration for BOPF and EAF
sources. . 4-45
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2. INTRODUCTION
2.1 BACKGROUND AND AUTHORITY FOR STANDARDS
Before standards of performance are proposed as a Federal regulation,
air pollution control methods available to the affected industry and the
associated costs of installing and maintaining the control equipment are
examined in detail. Various levels of control, based on different technolo-
gies and degrees of efficiency, are expressed as regulatory alternatives.
Each of these alternatives is studied by the U.S. Environmental Protection
Agency (EPA) as a prospective basis for a standard. The alternatives are
investigated in terms of their impacts on the economics and well-being of
the industry, the impacts on the national economy, and impacts on the
environment. This document summarizes the information obtained through
these studies so interested persons will be able to see the information
considered by EPA in the development of the proposed standards.
Standards of performance for new stationary sources are established
under Section 111 of the Clean Air Act (42 USC 7411) as amended, herein
referred to as the Act. Section 111 directs the Administrator to establish
standards of performance for any category of new stationary source of air
pollution that ". . . causes, or contributes significantly to air pollution
which may reasonably be anticipated to endanger public health or welfare."
The Act requires that standards of performance for stationary sources
reflect ". . . the degree of emission reduction achievable which (taking
into consideration the cost of achieving such emission reduction, and any
nonair quality health and environmental impact and energy requirements) the
Administrator determines has been adequately demonstrated for that category
of sources." The standards apply only to stationary sources, the construc-
tion or modification of which commences after regulations are proposed by
publication in the Federal Register.
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The 1977 amendments to the Act altered or added numerous provisions
that apply to the process of establishing standards of performance.
• EPA is required to list the categories of major stationary sources
that have not already been listed and regulated under standards of perform-
ance. Regulations must be promulgated for these new categories on the
following schedule:
a. 25 percent of the listed categories by August 7, 1980,
b. 75 percent of the listed categories by August 7, 1981, and
c. 100 percent of the listed categories by August 7, 1982.
A governor of a State may apply to the Administrator to add a category not
on the list or may apply to the Administrator to have a standard of perform-
ance revised.
• EPA is required to review the standards of performance every 4
years and, if appropriate, to revise them.
• EPA is authorized to promulgate a standard based on design, equip-
ment, work practice, or operational procedures when a standard based on
emission levels is not feasible.
• The term "standards of performance" is redefined, and a new term,
"technological system of continuous emission reduction," is defined. The
new definitions clarify that the control system must be continuous and may
include a low- or nonpolluting process or operation.
• The time between the proposal and promulgation of a standard under
Section 111 of the Act may be extended to 6 months.
Standards of performance, by themselves, do not guarantee protection
of health or welfare because they are not designed to achieve any specific
air quality levels. Rather, they are designed to reflect the degree of
emission limitation achievable through application of the best adequately
demonstrated technological system of continuous emission reduction, consider-
ing the cost of achieving such emission reduction, any nonair-quality
health and environmental impacts, and energy requirements.
Congress had several reasons for including these requirements. First,
standards with a degree of uniformity are needed to prevent situations
where some States may attract industries by relaxing standards relative to
other States. Second, stringent standards enhance the potential for long-
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term growth. Third, stringent standards may help achieve long-term cost
savings by eliminating the need for more expensive retrofitting when pollu-
tion ceilings may be reduced in the future. Fourth, certain types of
standards for coal burning sources can adversely affect the coal market by
driving up the price of low-sulfur coal or effectively excluding certain
coals from the reserve base because their untreated pollution potentials
are high. Congress does not intend for New Source Performance Standards to
contribute to these problems. Fifth, the standard-setting process should
create incentives for improved technology.
Promulgation of standards of performance does not prevent State or
local agencies from adopting more stringent emission limitations for the
same sources. States are free under Section 116 of the Act to establish
even more stringent emission limits than those established under Section 111
or those necessary to attain or maintain the National Ambient Air Quality
Standards (NAAQS) under Section 110. Thus, new sources may in some cases
be subject to limitations more stringent than standards of performance
under Section 111, and prospective owners and operators of new sources
should be aware of this possibility in planning for such facilities.
A similar situation may arise when a major emitting facility is to be
constructed in a geographic area that falls under the prevention of signif-
icant deterioration of air quality provisions of Part C of the Act. These
provisions require, among other things, that major emitting facilities to
be constructed in such areas are to be subject to best available control
technology. The term best available control technology (BACT), as defined
in the Act, means:
... an emission limitation based on the maximum degree of
reduction of each pollutant subject to regulation under this
Act emitted from, or which results from, any major emitting
facility, which the permitting authority, on a case-by-case
basis, taking into account energy, environmental, and economic
impacts and other costs, determines is achievable for such
facility through application of production processes and avail-
able methods, systems, and techniques, including fuel cleaning
or treatment or innovative fuel combustion techniques for
control of each such pollutant. In no event shall application
of "best available control technology" result in emissions of
any pollutants which will exceed the emissions allowed by any
applicable standard established pursuant to section 111 or 112
of this Act. (Section 169[3j)
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Where feasible standards of performance are normally structured in
terms of numerical emission limits. However, alternative approaches are
sometimes necessary. In some cases physical measurement of emissions from
a new source may be impractical or exorbitantly expensive. Section lll(h)
provides that the Administrator may promulgate a design or equipment stand-
ard in cases where it is not feasible to prescribe or enforce a standard of
performance. For example, hydrocarbon emissions from storage vessels for
petroleum liquids are greatest during tank filling. The nature of the
emissions—high concentrations for short periods during filling and low
concentrations for longer periods during storage—and the configuration of
storage tanks make direct emission measurement impractical. Therefore, a
more practical approach to standards of performance for storage vessels has
been equipment specification.
In addition, Section lll(j) authorizes the Administrator to grant
waivers of compliance to permit a source to use innovative continuous
emission control technology. To grant the waiver, the Administrator must
find:
A substantial likelihood that the technology will produce greater
emission reductions than the standards require or an equivalent
reduction at lower economic, energy, or environmental cost;
The proposed system has not been adequately demonstrated;
The technology will not cause or contribute to an unreasonable
risk to the public health, welfare, or safety;
The governor of the State where the source is located consents;
and
The waiver will not prevent the attainment or maintenance of any
ambient standard. A waiver may have conditions attached to
ensure that the source will not prevent attainment of any NAAQS.
Any such condition will have the force of a performance standard.
Finally, waivers have definite end dates and may be terminated
earlier if the conditions are not met or if the system fails to
perform as expected. In such a case, the source may be given up
to 3 years to meet the standards with a mandatory progress schedule.
2.2 SELECTION OF CATEGORIES OF STATIONARY SOURCES
Section 111 of the Act directs the Adminstrator to list categories of
stationary sources. The Administrator "... shall include a category of
sources in such list if in his judgment it causes, or contributes signifi-
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cantly to, air pollution which may reasonably be anticipated to endanger
public health or welfare." Proposal and promulgation of standards of
performance are to follow.
Since passage of the Clean Air Amendments of 1970, considerable atten-
tion has been given to the development of a system for assigning priorities
to various source categories. The approach specifies areas of interest
consideration of the broad strategy of the Agency for implementing the
Clean Air Act. Often, these "areas" are actually pollutants emitted by
stationary sources. Source categories that emit these pollutants are
evaluated and ranked by a process involving such factors as:
Level of emission control (if any) already required by State
regulations,
Estimated levels of control that might be required from standards
of performance for the source category,
Projections of growth and replacement of existing facilities for
the source category, and
Estimated incremental amount of air pollution that could be
prevented in a preselected future year by standards of perform-
ance for the source category.
Sources for which new source performance standards were promulgated or
under development during 1977, or earlier, were selected on these criteria.
The Act amendments of August 1977 establish specific criteria to be
used in determining priorities for all major source categories not yet
listed by EPA. These are:
The quantity of air pollutant emissions that each such category
will emit, or will be designed to emit;
The extent to which each such pollutant may reasonably be antici-
pated to endanger public health or welfare; and
The mobility and competitive nature of each such category of
sources and the consequent need for nationally applicable new
source standards of performance.
The Administrator is to promulgate standards for these categories
according to the schedule referred to earlier.
In some cases it may not be feasible to develop a standard for a
source category with a high priority immediately. This problem might arise
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when a program of research is needed to develop control techniques or
because techniques for sampling and measuring emissions may require refine-
ment. In the development of standards, differences in the time required to
complete the necessary investigation for different source categories must
also be considered. For example, substantially more time may be necessary
if numerous pollutants must be investigated from a single source category.
Further, even late in the development process the schedule for completion
of a standard may change. For example, inablility to obtain emission data
from well-controlled sources in time to pursue the development process in a
systematic fashion may force a change in scheduling. Nevertheless, priority
ranking is, and will continue to be, used to establish the order in which
projects are initiated and resources assigned.
After the source category has been chosen, the types of facilities
within the source category to which the standard will apply must be deter-
mined. A source category may have several facilities that cause air pollu-
tion, and emissions from some of these facilities may vary from insignificant
to very expensive to control. Economic studies of the source category and
of applicable control technology may show that air pollution control is
better served by applying standards to the more severe pollution sources.
For this reason, and because there is no adequately demonstrated system for
controlling emissions from certain facilities, standards often do not apply
to all facilities at a source. For the same reasons, the standards may not
apply to all air pollutants emitted. Thus, although a source category may
be selected to be covered by a standard of performance, not all pollutants
or facilities within that source category may be covered by the standards.
2.3 PROCEDURE FOR DEVELOPMENT OF STANDARDS OF PERFORMANCE
Standards of performance must:
Realistically reflect best demonstrated control practice;
Adequately consider the cost, the nonair-quality health and
environmental impacts, and the energy requirements of such control;
Be applicable to existing sources that are modified or reconstructed
as well as new installations; and
Meet these conditions for all variations of operating conditions
considered anywhere in the country.
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The objective of a program for developing standards is to identify the
best technological system of continuous emission reduction that has been
adequately demonstrated. The standard-setting process involves three
principal phases of activity: information gathering, analysis of the
information, and development of the standard of performance.
During the information-gathering phase, industries are queried through
a telephone survey, letters of inquiry, and plant visits by EPA representa-
tives. Information is also gathered from many other sources, and a litera-
ture search is conducted. From the knowledge acquired about the industry,
EPA selects certain plants at which emission tests are conducted to provide
reliable data that characterize the pollutant emissions from well-controlled
existing facilities.
In the second phase of a project, the information about the industry
and the pollutants emitted is used in analytical studies. Hypothetical
"model plants" are defined to provide a common basis for analysis. The
model plant definitions, national pollutant emission data, and existing
State regulations governing emissions from the source category are then
used in establishing "regulatory alternatives." These regulatory alterna-
tives are essentially different levels of emission control.
EPA conducts studies to determine the impact of each regulatory alter-
native on the economics of the industry and on the national economy, on the
environment, and on energy consumption. From several possibly applicable
alternatives, EPA selects the single most plausible regulatory alternative
as the basis for a standard of performance for the source category under
study.
In the third phase of a project, the selected regulatory alternative
is translated into a standard of performance, which, in turn^ is written in
the form of a Federal regulation. The Federal regulation, when applied to
newly constructed plants, will limit emissions to the levels indicated in
the selected regulatory alternative.
As early as is practical in each standard-setting project, EPA repre-
sentatives discuss with members of the National Air Pollution Control
Techniques Advisory Committee (NAPCTAC) the possibilities of a standard and
the form it might take. Industry representatives and other interested
parties also participate in these meetings.
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The information acquired in the project is summarized in the Background
Information Document (BID). The BID, the standard, and a preamble explain-
ing the standard are widely circulated to the industry being considered for
control, environmental groups, other government agencies, and offices
within EPA. Through this extensive review process, the points of view of
expert reviewers are considered as changes are made to the documentation.
A "proposal package" is assembled and sent through the offices of EPA
Assistant Administrators for concurrence before the proposed standards are
officially endorsed by the EPA Administrator. After they are approved by
the Administrator, the preamble and the proposed regulation are published
in the Federal Register.
As a part of the Federal Register announcement of the proposed stand-
ards, the public is invited to participate in the standard-setting process.
EPA invites written comments on the proposal and also holds a public hear-
ing to discuss the proposed standards with interested parties. All public
comments are summarized and incorporated into a second volume of the BID.
All information reviewed and generated in studies in support of the standard
of performance is available to the public in a "docket" on file in Washington,
DC.
Comments from the public are evaluated, and the standard of performance
may be altered in response to the comments.
The significant comments and EPA's position on the issues raised are
included in the "preamble" of a "promulgation package," which also contains
the draft of the final regulation. The regulation is then subjected to
another round of review and refinement until it is approved by the EPA
Administrator. After the Administrator signs the regulation, it is pub-
lished as a "final rule" in the Federal Register.
2.4 CONSIDERATION OF COSTS
Section 317 of the Act requires an economic impact assessment with
respect to any standard of performance established under Section 111 of the
Act. The assessment is required to contain an analysis of:
Costs of compliance with the regulation, including the extent to
which the cost of compliance varies, depending on the effective
date of the regulation and the development of less expensive or
more efficient methods of compliance;
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Potential inflationary or recessionary effects of the regulation;
Effects the regulation might have on small business with respect
to competition;
Effects of the regulation on consumer costs; and
Effects of the regulation on energy use.
Section 317 also requires that the economic impact assessment be as extensive
as practicable.
The economic impact of a proposed standard upon an industry is usually
addressed both in absolute terms and in terms of the control costs that
would be incurred as a result of compliance with typical, existing State
control regulations. An incremental approach is necessary because both new
and existing plants would be required to comply with State regulations in
the absence of a Federal standard of performance. This approach requires a
detailed analysis of the economic impact from the cost differential that
would exist between a proposed standard of performance and the typical
State standard.
Air pollutant emissions may cause water pollution problems, and captured
potential air pollutants may pose a solid waste disposal problem. The
total environmental impact of an emission source must, therefore, be analyzed
and the costs determined whenever possible.
A thorough study of the profitability and price-setting mechanisms of
the industry is essential to the analysis so an accurate estimate of potential
adverse economic impacts can be made for proposed standards. It is also
essential to know the capital requirements for pollution control systems
already placed on plants so additional capital requirements necessitated by
these Federal standards can be placed in proper perspective. Finally, it
is necessary to assess the availability of capital to provide the additional
control equipment needed to meet the standards of performance.
2.5 CONSIDERATION OF ENVIRONMENTAL IMPACTS
Section 102(2)(C) of the National Environmental Policy Act (NEPA) of
1969 requires Federal agencies to prepare detailed environmental impact
statements on proposals for legislation and other major Federal actions
significantly affecting the quality of the human environment. The objective
of NEPA is to build into the decisionmaking process of Federal agencies a
careful consideration of all environmental aspects of proposed actions.
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In a number of legal challenges to standards of performance for various
industries, the United States Court of Appeals for the District of Columbia
Circuit has held that environmental impact statements need not be prepared
by the Agency for proposed actions under Section 111 of the Clean Air Act.
Essentially, the Court of Appeals has determined that the best system of
emission reduction requires the Administrator to take into account counter-
productive environmental effects of a proposed standard, as well as economic
costs to the industry. On this basis, therefore, the Court established a
narrow exemption from NEPA for EPA determination under Section 111.
In addition to these judicial determinations, the Energy Supply and
Environmental Coordination Act (ESECA) of 1974 (PL-93-319) specifically
exempted proposed actions under the Clean Air Act from NEPA requirements.
According to Section 7(c)(l), "No action taken under the Clean Air Act
shall be deemed a major Federal action significantly affecting the quality
of the human environment within the meaning of the National Environmental
Policy Act of 1969." (15 USC 793c[l])
Nevertheless, the Agency has concluded that the preparation of environ-
mental impact statements could have beneficial effects on certain regulatory
actions. Consequently., although not legally required to do so by section 102
(2)(C) of NEPA, EPA has adopted a policy requiring that environmental
impact statements be prepared for various regulatory actions, including
standards of performance developed under Section 111 of the Act. This
voluntary preparation of environmental impact statements, however, in no
way legally subjects the Agency to NEPA requirements.
To implement this policy, a separate section in this document is
devoted solely to an analysis of the potential environmental impacts associ-
ated with the proposed standards. Both adverse and beneficial impacts in
such areas as air and water pollution, increased solid waste disposal, and
increased energy consumption are discussed.
2.6 IMPACT ON EXISTING SOURCES
Section 111 of the Act defines a new source as ". . . any stationary
source, the construction or modification of which is commenced ..." after
the proposed standards are published. An existing source is redefined as a
new source if "modified" or "reconstructed" as defined in amendments to the
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general provisions of Subpart A of 40 CFR Part 60, which were promulgated
in the Federal Register on December 16, 1975 (40 FR 58416).
Promulgation of a standard of performance requires States to establish
standards of performance for existing sources in the same industry under
Section 111 (d) of the Act if the standard for new sources limits emissions
of a designated pollutant (i.e., a pollutant for which air quality criteria
have not been issued under Section 108 or which has not been listed as a
hazardous pollutant under Section 112). If a State does not act, EPA must
establish such standards. General provisions outlining procedures for
control of existing sources under Section lll(d) were promulgated Novem-
ber 17, 1975, as Subpart B of 40 CFR Part 60 (40 FR 53340).
2.7 REVISION OF STANDARDS OF PERFORMANCE
Congress was aware that the level of air pollution control achievable
by any industry may improve with technological advances. Accordingly,
Section 111 of the Act provides that the Administrator ". . . shall, at
least every 4 years, review and, if appropriate, revise ..." the standards.
Revisions are made to ensure that the standards continue to reflect the
best systems that become available in the future. Such revisions will not
be retroactive, but will apply to stationary sources constructed or modified
after proposal of the revised standards.
2-11
-------
3. BASIC OXYGEN PROCESS STEELMAKING INDUSTRY
3.1 GENERAL
Making steel by the process of blowing air through molten iron was de-
veloped about a century ago, and has been practiced until the 1960's in the
form of the Bessemer converter. This process has the advantage of being
relatively fast, producing a high material to labor ratio. The open hearth
process could not be replaced by the blowing process, however, because
steel produced by blowing air through iron contains nitrogen, which makes
it more brittle and less ductile.
With the advent of tonnage quantities of pure oxygen (95 to 99 percent)
at low prices, the pure oxygen blown steelmaking process became feasible
and quickly grew from 1960 on, with a proportionate decline in the open
hearth process. The new process is effected in furnaces called Basic Oxygen
Process Furnaces (BOPF). The BOPF technology is now well established for
making high quality steel utilizing a minimum amount of labor. In 1978 the
domestic steel industry was composed of 93 companies operating 158 individ-
ual plants. The plants may be divided into three groups based on the type
of primary operations, products, and marketing approach of the individual
companies. These groups are: integrated companies that have primary raw
material and ironmaking facilities (blast furnaces), steelmaking units, and
finishing mills; alloy and specialty steel companies produce alloys and
special steels but do not engage in ironmaking activities; and noninte-
grated companies that operate melting and casting units and fabrication
mills for the production of a limited number of products for a regional
market.1 BOPF shops are typically part of integrated steel mills. A
schematic flow chart for integrated and nonintegrated steel mills is
presented in Figure 3-1.
A list of the integrated steel mills that have BOPF facilities is
presented in Table 3-1. The distribution of these plants within the United
States is shown in Figure 3-2.2
3-1
-------
Raw materials
preparation
(iron ore,
limestone)
Ironmaking
Coking
Blast
furnace
- .Pig :
iron
_ Basic oxygen
Scrap
Direct reduction
Steel making
furnace
Open hearth
Electric arc
DRI
Final hot rolling,
cold rolling,
finishing,
annealing, etc.
Ingot
casting
Ingot
breakdown,
primary
rolling
Finishing
Continuous
casting
Possible major routes:
Integrated:
Nonintegrated:
Semi-integrated:
coking-blast furnace-basic oxygen-ingot
casting-finishing.
scrap-electric furnace-continuous casting-finishing.
direct reduction + scrap-electric furnace-continuous
casting-finishing.
SOURCE: Office of Technology Assessment
Figure 3-1.
Schematic flow chart for integrated and nonintegrated
steelmaking.
3-2
-------
TABLE 3-1. BOPF LOCATIONS AND DESIGN CAPACITIES2
EPA
Region
2
3
4
5
3
9
Company
Sethi ahem Steel Co.
Republic Steal Co.
Alan Wood Steel Co.
Alleghany Ludlua
Steal Co.
BethlahM Stael
Corp.
Bethlehem Sttal
Corp.
Crucible, Inc.
Jones & Laugh] in
Steel Corp.
Jones & Laugh Hn
Steel Corp.
National Steel
Corp.
Sharon Stael Corp.
U.S. Steel Corp.
U.S. Steel Corp.
Wheeling-Pitts-
burgh Steel Corp.
Armco Steel Corp.
Republic Steel
Corp.
U.S. Steel Corp.
Armco Steel Corp.
Bethlehem Steel Co.
Bethlehem Steel Co.
Ford Motor Co.
Inland Steel Co.
Inland Steel Co.
Inter lake. Inc.
Jones & Laugh lin
Steel Corp.
McLoutn Steel Corp.
National Steel
Corp.
National Stael
Corp.
National Steel
Corp.
Republic Steal
Corp.
Republic Steel
Corp.
Republic Steel
Corp.
U.S. Steel Corp.
U.S. Steel Corp.
U.S. Steel Corp.
U.S. Steel Corp.
Wheeling-Pitts'
burgh Steel Corp.
Wisconsin Steel
Youngstown Sheet
& Tube Co.
CFS.I Steel Corp.
Kaiser Steel Corp.
Kaiser Steel Corp.
Location
Lackawanna, N.Y.
Buffalo, N.Y.
Conshohocken, Pa.
Matrons, Pa.
Sparrows Pt. , Md.
Bethlehem, Pa.
Midland, Pa.
AHquippa, Pa.
Aliquippa, Pa.
Weirton, W. Va.
Parrel 1, Pa.
Duquesna, Pa.
Braddock, Pa.
Hones sen. Pa.
Ashland, Ky.
Gadsden, Ala.
Fairfield, Ala.
Hiddletown, Oh.
Burns Harbor, Ind.
Burns Harbor, Ind.
Dearborn, Mich.
East Chicago, 111.
East Chicago, 111.
Chicago, 111.
Cleveland, Oh.
Trenton, Mich.
Ecorse, Mich.
Ecorse, Mich.
Granite City, 111.
Warren, Oh.
Cleveland, Oh.
So. Chicago, 111.
Gary, Ind.
Gary, Ind.
So. Chicago, 111.
Lorain, Oh.
Steubenville, Oh.
So. Chicago, 111.
East Chicago, 111.
Pueblo, Colo.
Fontana, Calif.
Fontana, Calif.
Year
installed
1964/66
1970
1968
1966
1966
1963
1968
1957
1963
1967
1974
1963
1972
1964
1963
1265
1974/78
1969
1969
1978
1964
1966
1974
1959
1961
1958/59
1962
1970
1967
1965
1966/77
1976
1965
1973
1969
1971
1965
1964
1970
1961
1958
1978
BOPF
Number
3
2
2
2
2
2
2
2
3
2
3a
2
2
2
2
2
k
3b
2
2
1
2
2
2
2
2
5
2
2
2
2
2
h
2b
3b
3B
3
2
2
2
2
2
3
2
furnaces
Size-Mg (tons)
270(300)
120(130)
135(150)
75(80)
195(215)
240(270)
95(105)
75(80)
170(190)
350(320)
135(150)
195(215)
210(230)
180(200)
165(180)
165(180)
130(200)
190(210)
270(300)
270(300)
225(250)
230(255)
190(210)
70(75)
205(225)
100(110)
270(300)
215(235)
215(235)
170(190)
220(245)
180(200)
195(215)
180(200)
180(200)
205(225)
260(285)
110(120)
255(280)
110(120)
110(120)
205(225)
Caoacity
MM Mg/year
MM(ton*/»r)
4.5(5.0)
0.9(1.0)
1.8(2.0)
0.4(0.5)
2.7(3.0)
3.1(3.5)
,0.9(1.0),
'6.0(6.7)'
5.2(5.8)
1.4(1.6)
2.2(2.5)
2.2(2.5)
1.4(1.6)
1.8(2.0)
1.3(1.5)
3.2(3.5)
2.0(2.3)
4.0(4.5)
0.9(1.0)
3,4(3.8)
,6.0(6.7),
t i
0.9(1.1)
2.7(3.0)
2.5(2.8)
5.2(5.8)
2.2(2.5)
1.9(2.2)
3.3(3.7)
2.0(2.3)
f 7. 2(8.0)
I
2.7(3.0)
2.7(3.0)
2.6(2.9)
1.0(1.2)
2.7(3.0)
1.2(1.*)
1.5(1.8)
2.1(2.4)
Notes:
aThis facility consists of one standard top-blown SOPF and two Xaldo Process SOPFs, the latter vessels being
inclined and rotating during the oxygen blow. The Xaldo units have Been virtually ;uoplanted by the standard
fixed unit (EPA, 1977).
bq-BOPF Installation.
SOURCES: U.S. House of Representatives, 1977
EPA. 1977
Nicola, 1973.
3-3
-------
,0 ...
^*=
~IX *
•••*....
HA'.VAII
5>
^
Legend
• RAW STEEL - BOPF
PRODUCING CENTERS
SOURCE: U.S. House of
Representatives, 1977.
Figure 3-2. Geographic Distribution of the U.S. Iron and Steel BOPF Steelmaking Facilities.
-------
3.2 PROCESS FACILITIES AND THEIR EMISSIONS
3.2.1 Basic Oxygen Process Furnaces and Their Operation
A basic oxygen process furnace is a large open-mouthed vessel lined
with a basic refractory material (the term "basic" refers to the chemical
characteristic of the lining). The furnace is mounted on trunnions that
allow it to be rotated through 360° in either direction. A typical vessel
can be 12 to 14 feet across and 20 to 30 feet high. A BOPF receives a
charge composed of scrap and molten iron and converts it to molten steel.
This is accomplished with a jet of high purity oxygen which oxidizes the
carbon and the silicon in the molten iron, removes these products, and
provides heat for melting the scrap. After the oxygen blow is started,
lime, usually in the form of pebble lime, may be added to the top of the
bath to provide a slag of the desired basicity. Fluorspar and mill scale
may also be added in order to achieve the desired slag fluidity.
Two types of furnaces are currently in use. The most common type is
the "top blown" furnace in which oxygen is blown into the vessel through a
water cooled lance suspended above the mouth of the furnace. During the
oxygen blow the lance is lowered into the mouth of the upright furnace.
The second type of furnace is the "bottom blown" Q-BOPF. In this furnace
oxygen is introduced into the vessel through tuyeres (openings) in the
furnace bottom. The production of steel by the basic oxygen process
proceeds in distinct steps or operations. In the order of their occurrence,
they are:
1. Charging—The addition of scrap metal or hot metal to the BOPF.
2. Oxygen Blow—The refining stage of the process in which pure
oxygen is blown into the BOPF.
3. Turndown—After the blow the vessel is tilted toward the charging
aisle to facilitate taking hot metal samples and making tempera-
ture measurements.
4. Reblow—If the samples taken during the turndown indicate the
need, oxygen can again be blown into the vessel, usually for only
a very brief period.
5. Tapping—Pouring the molten steel out of the BOPF into the teeming
ladle.
6. Deslagging—Pouring residual slag out of the BOPF into a slag
pot.
3-5
-------
7. Teeming—The pouring of molten steel into ingot molds .
These operations are illustrated in Figures 3-3 and 3-4.
A BOPF shop is generally arranged in three parallel aisles. The
charging aisle has one or more cranes for conveying charge material, that
is, molten iron and scrap, to the furnace, as well as carrying ladles of
molten slag away from the furnace. The furnace aisle contains the furnaces,
collection hoods for fumes, lances for injecting the oxygen into the bath,
and the overhead bins for storing and metering out the various flux
materials and alloy additions. The pouring, teeming, or tapping aisle,
serves to handle the finished heats of steel. It has one or more overhead
cranes and facilities for pouring the molten steel either into ingot molds
or into continuous casting machines.
Adjacent to the charging aisle, there is a scrap yard with overhead
cranes where scrap is transferred from railroad cars into the charging
boxes. The charging boxes are moved by special railed cars from the scrap
yard into the charging aisle. Other railed cars under the furnace hold the
steel and slag ladles (teeming ladle and slag pots). These cars transfer
the slag ladles from under the furnace to the charging aisle and the steel
ladles to the teeming aisle.
During the oxygen blow, the oxygen lance is lowered through an opening
(the lance hole) in the top of the primary hood. It is stopped a short
distance above the bath of steel and the oxygen flow is initiated. The
vessel is upright during the blow allowing the fumes to pass directly from
the mouth of the furnace into the mouth of the primary hood. At other
times in the process, the vessel may be tilted so that the mouth of the
vessel does not align with the opening in the hood and capture of the fumes
by the primary hood is less likely (Figure 3-3). The vessel is tilted
toward the charging aisle for at least four of the operations; namely,
charging the scrap, charging with molten iron, sampling the heat for analy-
sis, and dumping the slag. The furnace is tilted toward the tapping aisle
usually only when pouring the finished heat of steel from the furnace into
the teeming ladle. Alloy additions may be made to the bath while it is
upright under the hood. However, additions are normally made to the teeming
ladle while it is being filled with steel from the furnace.
3-6
-------
CO
Lance
Primary hood
\ /Slag pot
Deslagging ' '
Op blowing
Turndown
Tapping
Figure 3-3. Steps for making steel by the Basic Oxygen Process.
-------
Scrap charge
Dead time
Hot metal charge
O2 blow
U)
i
00
Turndown
Tapping
Deslagging
Teeming (from
previous heat)
1.5
JL J. - -L — «
1.5
18 1
3
6
2
0
8 12 16 20 24
Time, Minutes
28
32
36 40
Figure 3-4. Time sequence of top blown 80PF operations. Numbers above the lines
indicate the approximate duration of that operation.
-------
There are several ancillary operations associated with the basic
oxygen process of making steel. The first is the scrap handling operation
described above. The next is the transfer of molten iron from the torpedo
car to the charging ladle and from the charging ladle to the furnace itself.
The handling of molten iron may include the operation of mechanically
skimming slag from the top of the bath of iron. A third operation is the
teeming of the finished steel into ingot molds or into continuous casting
machines. Finally, there is the handling and disposing of molten slag,
generally accomplished by carrying the ladle of slag to the end of the
charging aisle and pouring it on the ground or into slag pots where it is
allowed to cool. The solidified slag is then loaded into trucks or railroad
cars for transport to a disposal site. Alternately, the molten slag may be
carried directly to the disposal site by means of special trucks.
A BOPF shop generally has either two or three steelmaking vessels. In
three- vessel shops, one of the vessels is generally out of service while
the other two are in operation. In both types of shops, the operation of
the two on-line vessels is staggered so that blowing alternates from one
vessel to the other and so that two vessels are not blown at the same time.
A single oxygen blow usually lasts for 15 to 20 minutes.
Figure 3-5 is a schematic elevation of a typical two furnace shop and
indicates all of the facilities described above. Figure 3-6 shows a
schematic cross-section that indicates the various operating units.3
3.2.1.1 Material Flow. A flow sheet for steelmaking in the BOPF is
shown in Figure 3-7.
The principal components of the charge are scrap and molten iron.
Scrap usually arrives at the shop in railroad gondola cars and is trans-
ferred to the charging box by means of an overhead crane and magnet.
Molten iron is brought to the shop by means of railroad torpedo cars and is
transferred to the charging ladle at the hot metal transfer station. This
station is often equipped with a hood for capturing the emissions that
evolve during the transfer operation. When the furnace vessel is ready for
charging, it is tilted toward the charging aisle and the charging box is
lifted and emptied into the vessel. Next, the ladle of molten iron is
poured into the vessel over the scrap. The vessel is turned upright, the
oxygen lance lowered, and the blow commences. During the blow, lime and
3-9
-------
-LANCE
HOIST
RIGS
OJ
t
STORAGE
FLOOR
WEIGHING
FLOOR
BATCHING
FLOOR
SERVICE
FLOOR "
CONVEYOR
CONVEYOR
FROM
RAW-MATERIALS
STORAGE
BUILDING
OPERATING
FLOOR ~
GROUND
LEVEL"-
.1 I
STORAGE BINS
WEIGHING BINS
i T?utvjiiiiivi omo i
VAAAAj
r~L*-COKE
V-/ STOVE
OXYGEN LANCE
CONVEYOR
BATCHING HOPPER
BATCHING HOPPER
HOOD
FURNACE
TILTING
MECHANISM
LADLE
ADDITIVE
STORAGE
BINS
LADLE ADDITIVE
TRANSFER CAR
-STEEL
LADLES
Figure 3-5. BOPF—schematic elevation of a two furnace facility. Copyright 1971 by United States
Steel Corporation.
-------
CONVEYOR FROM
,RAW-MATERIAL
STORAGE
STORAGE BINS
WEIGHIN
BINS
CONVEYORS \ /
OXYGEN
LANCE
DOTTED LINES SHOW POSITIONS
OF TILTED FURNACE AND SCRAP
HOOD 80X WHEN CHARGING SCRAP
CHUTE
^
\ ^
SLAG POT ON
TRANSFER CAR
— 7 .-TEEMING
JO I f LADLE ON
^ - TRANSFER
T
\
SCRAP
CHARGING
CAR
r\
HOT-METAL
TRANSFER
LADLE ON
TRANSFER CAR
IN PIT
Figure 3-6.
BOPF—schematic cross-section of operating units.
Copyright 1971 by United States Steel Corporation.
3-11
-------
Molten iron from
blast furnace
Desulfurization (optional)
Hot metal transfer
Hot metal transfer _ -ia Iha.
emissions
95.5 tons hot metal
Skimming
195.5
Skimming a
Scrap
23.9 tons
Fluxes and coolants b
Basic oxygen
process furnace operations
emissions
Alloying additions b •
_ . 100 tons
Teeming -*-
steel
Turndown
O2 reblow -
(not always
needed)
j—Tapping
Deslagging'
Hot metal
charging
-38 IDS.
Emissions
Primary __ 3 QQQ Ib$
emissions
Turndown a
emissions
Reblow
a
emissions
Tapping^ 29 Ibs.
emissions
Deslagging a
emissions
Slag disposal
a quantities unknown
quantities vary from one heat to the next
Figure 3-7. Flow diagram for Basic Oxygen Process furnace operations,
3-12
-------
fluorspar in the desired quantities may be fed through the chute into the
vessel from the weight hopper.
Two forms of primary emission gas cleaning equipment are in common
use. One is the open hood which is similar to that shown in Figures 3-5
and 3-6. The gases that evolve during the oxygen blow are captured by the
hood, enter a hood cooling section where some heat is extracted, and pass
through a conditioning chamber where the gas is cooled to the required
temperature for the precipitator and at the same time humidified for proper
precipitator operation. The gas cleaning system usually consists of
precipitators, fans, dust handling equipment, and a stack for carrying away
the cleaned gases.
The other system is the closed hood in which the diameter of the entry
into the hood is roughly the same as the diameter of the mouth of the
vessel. The lower portion of the hood is equipped with a skirt that can be
dropped onto the mouth of the vessel, sealing off the space between the
hood and the vessel proper, thus limiting the amount of air that can enter
the system. The gases are collected in an uncombusted state; their volume
is reduced as compared to those in the open hood and the yield of the
process is increased. Because the gases remain combustible, gas cleaning
is performed by means of a scrubber, the precipitator being a potential
source of explosions. The cleaned gas is usually flared at the stack.3
Because there is no danger of explosion in the open hood system, all
of the vessels in the shop may be connected to a common gas cleaning system,
thereby effecting economies in installation. The closed system, on the
other hand, because of the danger of explosion, must have a separate
scrubber system for each vessel.
The flux bins are generally filled by a belt conveyor system from a
hopper at ground level. This hopper is usually equipped to be loaded from
a railroad car, a truck, or both. Transfer points of the conveyor system
are generally fitted with hooding and small individual baghouses.
When the heat is complete, the vessel is tilted and the steel is
poured into the teeming ladle. The transfer car moves the ladle into the
pouring aisle, and a crane picks up the ladle and carries it over to the
train of ingot molds parked at the teeming station. A stopper or slide
gate in the bottom of the ladle is opened and each ingot is filled in turn.
3-13
-------
Alternatively, the ladle may be carried to the top of a continuous casting
machine for the production of continuously cast products. After the steel
is out of the vessel, the slag is poured into a slag pot. When the pot is
filled, it is run into the charging aisle by means of a transfer car. The
charging crane then picks up the pot and carries it away for disposal.
The slag is sometimes disposed of by pouring it on the ground at one
end of the shop, where it is allowed to cool. Alternatively, the pot of
molten slag may be carried away from the shop and the slag processed in a
remote site. In either case, the metal!ics are generally removed from the
slag by magnetic means and returned to the blast furnace or sinter plant
and charged as a portion of the burden. The remaining slag is generally
disposed of in a dump area.3
3.2.1.2 Material Balance. As indicated on the flow sheet (Figure
3-7), in order to produce a metric ton of steel in the BOPF, the following
raw materials are required:
1. Ferrous charge materials consisting of molten iron, approximately
70 percent, and scrap, approximately 30 percent (higher percent-
ages of hot metal may be used if desired).3 The typical yield
in a BOPF with an open hood is 85 percent. Therefore, to produce
1000 kilograms (kg) (2205 pounds) of steel; 825 kg (1819 pounds)
of molten iron and 350 kg (772 pounds) of scrap are required. In
the closed hood, the yield increases to approximately 87 percent
and the use of molten iron and scrap drops correspondingly. Some
of the shops practice scrap preheating prior to the admission of
molten iron. This practice generally adds about 15 minutes to
the tap-to-tap time; however, less molten iron and more scrap may
be used. In general, the hot metal drops from 70 percent to 60
percent under scrap preheating.
2. Flux materials consisting of lime and fluorspar. Lime is the
principal ingredient. Its quantity is generally about 90 kg (198
pounds) per metric ton of steel and varies corresponding to the
sulfur content of the iron and the specification of the finished
steel in regard to freedom from sulfur. The quantity of fluorspar
is determined by the need to maintain a fluid slag and is
generally 3 percent by weight of the amount of lime.
Calculations presented elsewhere in this document are based upon the
assumption that 80 percent of the charge is hot metal and 20 percent is
scrap.
3-14
-------
3. Oxygen in the amount of 3.1 standard cubic meters per minute
(110 standard cubic feet per minute (scfm))per metric ton of
steel is injected into the bath. The amount of oxygen used
depends on two factors. One is the composition of the molten
iron, especially in respect to its content of such materials as
silicon and manganese. The other is the final carbon level re-
quired in the finished steel.
4. Ladle additions consist of alloying elements such as manganese,
nickel, chromium, etc., that are required in varying amounts, de-
pending upon the final composition of steel. In addition, the
aluminum reacts with oxygen forming aluminum oxide, most of which
migrates to and is included with the slag.
The basic oxygen process, in addition to producing steel, yields slag,
gases, and gas borne particulates. The amount of slag is essentially equal
to the amount of lime and spar that is added to the bath plus additions for
refining of the bath and minus the emissions of slag to the hood along with
the furnace gases.
The amount of gases from the furnace varies according to the type of
fume collection system employed. These include:
1. Open hood with ESP produces the greatest volume of gas, approxi-
mately 62 scmm per metric ton (2,000 scfm/ton) of steel. This
high value results from two causes. One is the absolute neces-
sity to combust completely all of the carbon monoxide that is
emitted from the furnace, thereby avoiding any possibility of
explosion in the precipitator. The other is that the precipita-
tor's having a low pressure drop, generally under 51 mm (2 in.)
of water gauge, does not result in high consumption of energy at
the fan, even though the volumes may be high. A supplementary
benefit of the high volume is that it facilitates the capture of
emissions from the mouth of the vessel when it is tilted
partially out of the hood to receive scrap and molten iron.
2. Open hood—wet scrubber generally produces less flow of gases
than does the precipitator, the amount being approximately 28
scmm per metric ton (900 scfm/ton) of steel. The reduced volume
results from the need to conserve energy in a scrubber system
3-15
-------
operating somewhere in the range of 127 to 178 centimeters (cm)
(50 to 70 inches) of water. Also, the presence of combustibles
in the scrubber system would not entail a significant risk of
explosion.
3. Closed hood--wet scrubber involves the least flow of any of the
three systems, appoximately 11.5 scmm per metric ton (360 scfm/
ton) of steel. This reduced value results because secondary air
to complete the combustion of carbon monoxide is not permitted to
enter the hood. Energy requirements for cleaning the gases in
the closed system, because of the sharply reduced volumes, are
lower than those for the open system.
The amount of particulates carried out of the furnace into the gas
cleaning system is approximately 6 to 20 kg per metric ton (12 to 40 pounds/
ton) of steel produced. Each of the gas cleaning systems described above
is capable of reducing the concentration of particulates in the clean gas
to the level of New Source Performance Standards, 50 milligrams per standard
cubic meter (mg/scm) (0.022 grains per standard cubic foot (gr/scf)) dry or
better. Therefore, the mass rate of particulates in the clean gas depends
essentially upon the volume of gas leaving the stack and, in turn, is
related to the type of cleaning system employed. The environmental
effectiveness of the three control systems ranked in terms of particulate
control from lowest emission rate to highest is the closed hood, the open
hood with a scrubber, and the open hood with a precipitator.3
3.2.1.3 Methods of Operation. Top blown furnace. In the basic
oxygen steel making process, molten iron is converted to steel using a jet
of oxygen to remove most of the carbon and silicon. The heat generated by
oxidation is used to melt scrap. Refining of impurities is accomplished by
means of the slag, the chief goal being to remove as much of the sulfur
from the steel as is possible. The desired specifications of the end
product are usually accomplished by the additions of suitable alloying
materials to the ladle of finished steel as it is filled.
A typical BOPF furnace produces a heat of steel in a very short time;
tap-to-tap times in a high performance shop may be as brief as 30 minutes.
To accomplish this the process is fully mechanized and, in addition, is
under some form of computer control. Computer control may be applied
3-16
-------
directly from the computer through electrical circuits to the furnace
however, the more usual practice is for the computer to provide information
for the operator who then controls the process. High performance depends
on equipment that is sophisticated and reliable. Both of these factors
tend not only to produce steel at a rapid rate, but also to avoid abnormal
operating conditions.
The lining of the BOPF furnace is made of high quality basic
refractory. During a campaign that may last 1000 heats or more, the linings
become worn generally near the slag line. These points of wear are patched
between heats by various gunning techniques (spraying of patching materials
onto the wear points). Eventually linings wear so much that the furnace
must be taken out of service, the refractory removed, and a new lining
installed. Approximately one week is required to remove the old lining and
replace it with a new one. During this period, the vessel is out of
service.
In a two-vessel shop, the vessels are alternately on-time. One vessel
is either being relined or, having been relined, is on standby and the
other vessel is in operation. (Some two-vessel shops operate both vessels
when the reline is complete.) In a three-vessel shop, the relining schedule
is arranged so that two vessels may be kept in operation. In this case,
the two operating vessels are alternated with respect to the flow of oxygen.
While one vessel is being blown, the other is being tapped and being
recharged.
When an upset occurs of potential damage to equipment, the environment,
or the process itself, the process can be shut down instantly by stopping
the flow of oxygen and raising the lance. The heat may remain in the
vessel for a relatively long period of time, possibly 6 or more hours,
until necessary repairs have been made. However, dumping the heat is
preferable in the case of a long delay.
The hood that conveys the gases away from the furnace is water cooled.
Water may be recirculated through a heat exchanger and returned again for
use in the hood. Alternatively, the water may be converted to steam and
delivered to other steel making operations. On some steam generating hoods,
fuel is fired into the hood between blow periods in order to maintain a
constant rate of steam output. Another way of maintaining the output at a
3-17
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constant rate is to use a steam accumulator; however, the generation of
steam per ton of steel is less with this method because no supplementary
fuel is used.
As indicated above, it is possible to decrease the amount of molten
iron required by using a technique of scrap preheating. This is accomp-
lished by means of a second lance inserted in place of the oxygen lance.
The second lance injects oxygen and natural gas or oil and pre-heats the
scrap to a glowing red color. After preheating the scrap, the lance is
withdrawn and the oxygen lance lowered in its place. The vessel is tilted
and molten iron is poured into it. Pouring of molten iron over the heated
scrap results in a violent reaction and the production of copious emissions.
The pouring rate must be carefully controlled in order to insure that the
hood may capture substantially all of the emissions.3
Bottom blown furnace. The Q-BOPF process offers an alternative to the
use of an oxygen lance. This is the latest version of the basic oxygen
process and is similar to a process developed by Oxygen Blasen
Maximillian-Huette, Bavaria, Germany (OBM process). The Q-BOPF process is
now being licensed in the United States by U.S. Steel Corporation.
The Q-BOPF process is carried out in a modified basic-lined converter
that is fitted with bottom tuyeres through which both oxygen and a hydro-
carbon gas are injected. Concentric tuyeres are built into the bottom so
that the oxygen enters the bath shrouded by a shield of hydrocarbon gas
through the larger of two concentric pipes. On entry into the vessel, the
hydrocarbon is cracked endothermically, thus absorbing the heat that would
otherwise be liberated where the oxygen first contacts the molten metal.
This absorption of heat protects tuyeres from the rapid erosion that took
place in previous attempts to bottom blow with oxygen. The fact that the
oxygen is blown through the bottom rather than from above changes the
character of the slag. Powdered lime is blown in through the bottom tuyeres
with the oxygen to assist in obtaining a slag that is effective in removing
phosphorus and sulfur from the bath. This slag apparently develops a much
lower iron oxide content than the slags made in the conventional basic
oxygen process.
The principal advantage claimed for the Q-BOPF is that it requires
less headroom in the furnace aisle than does the BOPF. This has allowed
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the Q-BOPF to be installed in an existing open hearth building, thereby
saving cost in construction of the facility. Other advantages include:
1. Lower capital investment (for either new plants or open hearth
conversions),
2. Lower operating cost,
3. Higher productivity, and
4. Better metallurgical product.
Of the 14 BOPFs, that have come on stream in the last 5 years (through
1978), 8 are of Q-BOPF design. Seven of the eight represent open hearth
steelmaking shop conversions, and the eighth (U.S. Steel, Fairfield, Alabam
a) is a new Q-BOPF started up in 1978.2
When the Q-BOPF vessel is tilted to receive scrap and molten iron or
to sample for steel analysis, it is necessary to maintain a flow through
the tuyeres so that they do not become blocked. In normal practice, the
oxygen and natural gas are turned off when the vessel is tilted and these
gases are replaced by a flow of nitrogen. In any event, there is a copious
flow of emissions of fumes from the mouth of the vessel due to the gas flow
from the tuyeres. For this reason, the Q-BOPF needs to be more fully
enclosed at the level of the charging floor than is the BOPF. A pair of
large horizontally sliding doors assist in directing the gases back into
the collection system and protecting the men who are on the charging floor.
These doors are opened only to permit the addition of scrap and molten iron
and are closed at all other times.3
3.2.2 Process Emissions
Air Pollution. The operations in the BOPF shop are directly
responsible for two general categories of pollution, namely, air pollution
and solid waste. Water pollution, where it occurs, is invariably a
by-product of gas cleaning operations.
There are two principal types of air pollution. The first is the
direct result of the steelmaking process itself and consists of dense emis-
sions of fumes from the mouth of the basic oxygen vessel. The fumes are
mostly metallic oxides that result from the reaction between the jet of
oxygen and the molten bath. Also included in these fumes are particles of
slag. Carbon monoxide produced by the reaction of both carbon and oxygen
is also emitted. For some plants, raw materials used in the process con-
tain fluoride that is emitted during the blow.
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The gases that leave the mouth of the furnace, in addition to being
dusty, are extremely hot. In the closed hood system, temperatures are in
the neighborhood of 1650°C (3000°F). In the open system, CO combustion
takes place at the entrance of the hood, raising the temperature perhaps
another 540°C (1000°F). Before the gases may be cleaned of their particu-
late matter they must be cooled.3 The methods of cooling and cleaning the
gas are briefly described under in 3.2.1.2.
3.2.2.1 Fugitive Emission Sources. The second type of air pollution
source comprises a variety of operations from which the emissions are
generally classified as fugitive emissions. Emission factors for these
sources are listed in Table 3-5. Descriptions of the sources follow:
1. Reladling or "hot metal transfer" of molten iron from the torpedo
railroad car to the charging ladle is accompanied by the emis-
sions of kish, a mixture of fine iron oxide particulates together
with larger graphite particles. The usual method of control is
to provide a close fitting hood and a baghouse. A spark box
between the hood and the baghouse protects the bags from destruc-
tion by large hot particulates. Normally, the spark box is built
integrally with the baghouse.
2. Desulfurizing of molten iron may be accomplished by means of
various reagents such as soda ash, lime, or magnesium. Injection
of the reagents into the molten iron is accomplished
pneumatically, either with dry air or nitrogen. Desulfurizing
may take place at various locations within the iron and steelmak-
ing facility; however, if the location is the BOPF shop, then it
is most often accomplished at the reladling station to take
advantage of the fume collection system at that location.
3. Skimming of slag from the ladle of molten iron keeps this source
of high sulfur out of the steelmaking process. Skimming is often
done under a hood because it results in the emissions of kish.
The hood may be connected to a baghouse or to a vent stack.
4. Charging of scrap and molten iron into the BOPF vessel results in
a dense cloud of emissions. Emissions from the charging of scrap
are particularly severe if the scrap is dirty, oily, otherwise
contaminated, or contains such potential sources of explosion as
3-20
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water or ice. Emissions from the charging of molten iron are
particularly severe if the scrap over which it has been charged
is dirty or contaminated, or if the scrap has been preheated. In
some open hood shops, if the main hood is large enough and the
volume of air flow is sufficient, it is possible to capture most
of the fumes in the primary collection system for the vessel. In
this case, as much of the vessel mouth as possible is kept under
the hood and, in the case of pouring the iron, it is done at a
slow controlled rate. In other facilities, it is necessary to
provide auxiliary hoods in front of the main collection hood. On
occasion, a facility may also have a hood at the building monitor
to capture any fumes that bypass the hoods at the vessel.
5. Tapping of the molten steel from the BOPF vessel into the ladle
results in iron oxide fumes. The quantity of fumes is substan^
tially increased by additions into the ladle of alloying materials
such as silicon and manganese. Some BOPF facilities enclose the
space at the rear of the furnace in such a manner that the fumes
are ducted into the main collection system. In other facilities
the fumes are permitted to exit through the roof monitors.
6. Turn down of the vessel for the purpose of taking samples or for
pouring out the slag results in emissions. These emissions are
particularly copious in the case of the Q-BOPF because when the
vessel is turned down a flow of nitrogen must be maintained in
the tuyeres in the bottom of the vessel in order to keep out the
molten metal and slag. Some facilities have a pair of sliding
doors on the charging floor in front of the vessel. These doors
are kept closed as much as possible in order to direct the fumes
into the primary collection system.
7- Slag handling may consist of transporting the ladle of molten
slag from the shop to a remote dump area, or dumping the molten
slag on the ground at the end of the shop and allowing it to cool
there. The dumping of slag and its subsequent removal by
bulldozer is a very dusty operations that is generally
uncontrolled.
3-21
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8. Teeming of steel from the ladle to the ingot mold or continuous
caster results in emissions that are normally uncontrolled. In
some shops where leaded steels are poured, the resultant fumes
are extremely hazardous to the health of the workers. In these
cases, local hooding is provided.
9. Flux handling is effected with a sophisticated system comprised
of receiving hoppers for accepting deliveries from trucks or
railroad cars, a belt conveyor, large overhead storage bins,
weigh hoppers, feeders, and controls. Hooding is provided at the
various transfer points to capture the particulates that escape
when the bulk material falls. Exhaust ducts lead from the hoods
to one or more baghouses.
10. Skull burning and ladle dumping (ladle maintenance). The molten
steel that remains in the ladle after teeming may cool and
solidify between successive uses. After accumulating for some
time, these skulls may interfere with proper ladle operation. To
prevent this they are burned out with oxygen lances. This ladle
lancing procedure results in the emission of iron oxide fumes.
Ladles must also be relined at intervals to protect the steel
shell. The ladles are turned upside down to dump loose material
onto the shop floor. This generates fugitive dust. These sources
can be locally hooded, but normally are not.3
3.2.2.2 Nonprocess Sources of Fugitive Emssions. Two other sources
of pollution are those associated with the disposal of solid waste from the
process. The first results from the transportation and disposal of the
BOPF dust. Unless closed containers or trucks are used, the act of trans-
porting the dust can cause some of it to be re-entrained into the air. If
the dust is recycled to the ironmaking process, its disposal does not cause
further environmental problems. However, in most BOPF facilities, the
contaminants in the dust, principally oxides of zinc and tin, may cause
serious problems in the blast furnace. Rather than recycle the dust, the
operators find it necessary to either "store" it on the ground in the open
or dump it in a landfill. In either case, special precautions must be
taken to prevent wind from picking up the dust and re-entraining it into
the air or rain from leaching out toxic compounds from the dust and
delivering them to the underground aquifer or the nearby water course.
3-22
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The second source is the BOPF slag recycling operation. In a separate
facility, metal lies are recovered from the slag by magnets and returned to
the steelmaking operations. Some of the slag, because it is relatively low
in sulfur and high in Time, may be charged into the blast furnace. The
remaining slag is disposed of in the landfill. As with the dust, special
care is required to avoid the adverse aspects of leaching.3
There are no direct sources of water pollution associated with the
basic oxygen process. Those water pollution sources that may exist result
from the particular type of fume collection system employed. If a scrubber
is used, there is discharge of scrubber water. Normally, most of this is
recycled through a clarifier; however, facilities are required for dealing
with the necessary blowdown to the water system. Even the dry precipitator
may result in a discharge of contaminated water. This results from the
final step in gas cooling, which is the quenching and conditioning of the
gases by means of water spray. If the quantity of water used in condition-
ing or its method of application is not carefully controlled, there is an
overflow of water from the conditioning process that is contaminated with
BOPF dust and must be treated.3
3.2.3 Process Emissions Characterization
3.2.3.1 Emissions Generated During the Oxygen Blow. Particulate
matter emissions from BOPFs are produced primarily by refractory erosion
and by condensation of vaporized metal oxides and coagulation of these
particles to form agglomerates. Thus, BOPF particulate matter emissions
consist mainly of spherical particles or agglomerates of spherical particles
with similar properties.
Table 3-2 presents a typical particle-size distribution of open hood
BOPF primary particulate emissions. Other investigations have reported
that the mass mean diameter of particulates from top-blown BOPFs varies
between 0.5 and 1.0 micron. Particulates from bottom-blown BOPFs (Q-BOPFs)
are smaller and generally estimated to be about 0.1 micron in diameter.
A significant change in particle-size distribution appears to occur
when BOPF emissions are collected in closed hood gas collection systems as
compared with open hood gas collection systems. Table 3-3 presents a
typical particle-size distribution from a Japanese closed hood collection
system.
3-23
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TABLE 3-2. TYPICAL PARTICLE-SIZE DISTRIBUTION OF OPEN
HOOD, TOP BLOWN BOPF BLOWING EMISSIONS
Particle diameter (microns)
Weight (percent)
1-65
65-90
90-110
25
15
20
15
25
TABLE 3-3. PARTICLE-SIZE DISTRIBUTION OF CLOSED
HOOD, TOP BLOWN BOPF BLOWING EMISSIONS
Particle diameter (microns)
Weight (percent)
<5
5-10
10-20
20-30
>30
8.7
9.0
39.5
28.8
14.0
TABLE 3-4. COMPARISON OF PARTICULATE COMPOSITION FROM OPEN
AND CLOSED HOOD COLLECTION SYSTEMS3
Component
Open hood
collection process
(weight, percent)
Open hood
collection process
(weight, percent)
Fe total
Fe metal
Fe as FeO
Fe as Fe304, Fe203
CaO
Si02
59
—
1.6
57.4
2
1
75
10
63
2
2
1
Partial analysis is given in each case.
^Calculated by difference.
3-24
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Recognizing that these distributions may vary depending on operating
practice and analytical technique, it is probable that a much smaller per-
centage of the particulates from the closed hood collection system are in
the respirable range (< 5 microns in diameter).
In the closed hood collection process the dust is composed mainly of
iron oxide (FeO), magnetite, and small amounts of metallic iron. Because
FeO and magnetite agglomerate more easily than hematite, the dust particles
are larger than those obtained from the open hood collection process. In
the latter process, the particles consist of an outer surface of hematite
surrounding a core of magnetite.
Table 3-4 presents a comparison of the composition of particulates
from open and closed hood collection systems.
The particulate generation rate in the basic oxygen process depends on
several factors, including oxygen blow rate, carbon content of iron,
percentage of scrap charged, quality of scrap charged, rate of additions,
and condition of the refractory lining of the vessel. During the production
cycle the gas evolution rate and gas temperature vary considerably. Due to
the resultant variations in the concentration of particulate matter and gas
temperature and volume in the inlet gas stream, emissions are greater in
the beginning of the blowing period than during the remainder of the oxygen
blow and the rest of the cycle. About 30 pounds of particulates are
produced per ton of raw steel.2
3.2.3.2 Emissions from Secondary Sources. The secondary sources of
emissions within a BOPF shop are hot metal transfer, desulfurization,
skimming, charging, turndown, tapping, deslagging, teeming, ladle
maintenance, flux handling, slag handling, and disposal. The fugitive
nature of these emissions make them very difficult to study and quantify.
For this reason very little work has been done to characterize the
emissions from these secondary sources.
Emission factors have been developed for hot metal transfer, charging,
tapping, and teeming.4 These are listed in Table 3-5. Even less is known
about the particle-size distribution of these emissions. The size
distribution for Q-BOPF charging emissions is presented in Table 3-6. The
composition of BOPF fugitive emissions is presented in Table 3-7.
3-25
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TABLE 3-5. UNCONTROLLED EMISSION FACTORS FOR BOPF
SECONDARY EMISSIONS
Process Emission factor
Hot metal transfer 0.179 Ib/ton steel3 (0.192 Ib/ton hot
metal poured)
Skimming b
Scrap charge b
Hot metal charge
0,
poured)
,62 Ib/t
poured)
Turndown
Top blown 0.377 Ib/ton steel3 (0.4 Ib/ton hot metal
Bottom blown 0.62 Ib/ton steel3 (0.66 Ib/ton hot metal
Tapping
Top blown 0.291
Bottom blown 0.96
Deslagging b
Teeming 0.07
Slag handling b
Ladle maintenance b
Flux handling b
3Based on 85 percent furnance yield and 80 percent of charge being hot metal
No emission factors are available for these processes.
3-26
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TABLE 3-6. PARTICLE SIZE DISTRIBUTION FOR
Q-BOPF CHARGING EMISSIONS5
Percent of
Particle size particles within
range size range
<1.55M 3.1
1.55M-3.6M 30.2
3.6jj-10.5n 16.2
|j 50.2
3-27
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TABLE 3-7. COMPOSITION OF FUGITIVE EMISSIONS FROM BOPFs
CO
1
ro
CO
Facility
National Steel
Wierton, W.Va.
Colorado Fuel
& Iron Corp.
Pueblo, Col.
Colorado fuel
& Iron Corp.
Pueblo, Col.
Source of
fugitive emissions Fe
Hot metal charging
emissions:
a. Clean scrap in 13.1
initial charge
b. Galvanized scrap 3.3
in initial charge
c. Oily scrap in 11.3
initial charge
d. No. 2 bundles 3.8
in initial charge
(large % or gal-
vanized sheet
scrap)
Total fugitive
emissions as
collected at building
roof monitor
Baghouse particulate
collected from aux-
iliary hood capturing
charging and tapping
emissions
Benzene
soluble
FeO Fe203 CaO MgO Si02 PbO ZnO MnO C Cd organics
12.7 8.3 3.5 1.0 5.2 0.3 3.4 0.5 34.3
8.3 12.7 2.0 0.5 2.6 0.2 5.3 0.3 60.3
16.7 10.6 2.9 0.7 3.0 0.8 8.1 0.6 37.8 (a)
17.6 10.5 1.7 0.5 2.8 1.8 12.0 0.6 41.5
53.6 12.7 8.6 6.7 <4.1 6.8 1.1 3.2 <1.0 1.2
32.6 6.7 1.0 6.4 2.0 16.2 1.4 8 .2
Gaseous methane averaged 61 ppm.
-------
3.3 REFERENCES
1. Technology and Steel Industry Competitiveness. Congress of the United
States, Office of Technology Assessment. Washington, D.C. June 1980.
p. 186-188.
2. Drabkin, M. and R. Helfand, A Review of Standards of Performance for
New Stationary Sources—Iron and Steel Plants/Basic Oxygen Furnaces.
Metrek Division of the Mitre Corporation. McLean, Virginia. EPA-450/
3-78-116. November 1978. 65 p.
3. Coy, D. W. et al. Pollution Effects of Abnormal Operations in Iron
and Steelmaking--Volume VI. Basic Oxygen Process, Manual of Practice.
Research Triangle Institute, Research Triangle Park, North Carolina.
EPA-600/2-78-118f. June 1978. p. 3-18.
4. Cuscino, T. A., Jr. Particulate Emission Factors Applicable to the
Iron and Steel Industry. Midwest Research Institute, Kansas City,
Missouri. EPA-450/4-79-028. September 1979. p. 27-31.
5. Steiner, J. and J. Knirck. Particulate Matter Emissions Factor Tests
for Q-BOPF Hot Metal Addition and Tapping Operations at Republic
Steel, Chicago, Illinois. Acurex Corporation, Mountain View, Cali-
fornia. Acurex Project 7270. November 1978. p. 5-5.
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4. EMISSION CONTROL TECHNIQUES
4.1 INTRODUCTION
Primary control systems for BOPFs have been described amply in Chapter
3 and elsewhere.1 Briefly summarizing, the carbon monoxide produced may be
burned at the mouth of the vessel; then the particulate matter, the products
of combustion, and the excess air are drawn into an "open hood," cooled,
and cleaned by a wet scrubber or an electrostatic precipitator (ESP).
Alternatively, the gas may be cleaned instead before burning, to
reduce the temperature and volume of the gas to be cleaned. In this case a
carefully fitted "closed hood" is required and cleaning with a wet scrubber
is necessary because of the hazard of igniting this potentially flammable
gas in an; ESP.
Emissions during those steps in the cycle that require the vessel to
be tipped out from under the hood—scrap charging, hot metal charging,
sampling, tapping and deslagging--are often poorly controlled by the primary
system. Similarly, the ancillary operations of hot metal transfer and slag
skimming are not controlled at all by the primary system. Both ancillary
emissions and furnace emissions noted in this paragraph may be called
"secondary emissions." Other secondary emissions sources that may be found
in the BOPF shop that are desulfurization of hot metal, ladle repair, and
ladle deskulling. Teeming, flux handling, and slag handling are other
secondary emissions sources that are also present in the BOPF shop.
Performance data in this chapter include some emissions from these
latter sources. Furnace secondary particulate emissions typically are
produced by unconfined sources such as leaks from the primary furnace hood
or the open top of a ladle. With control these emissions must be captured
by enclosures or hoods. Once captured the emissions must be ducted to a
particulate control device. Capture techniques are as follows:
1) Furnace enclosures
2) Local hoods
4-1
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3) Building evacuation
a) Full
b) Partial
4) Adaptation of primary furnace hooding (for open hoods only)
Particulate removal techniques that can be used are as follows:
1) Baghouses
a) Pressurized
b) Suction
2) Electrostatic Precipitators
a) Classical
b) Roof-mounted
3) Scrubbers
This chapter describes specific control techniques for secondary furnace
emissions and for hot metal transfer and hot metal skimming.
4.2 CAPTURE OF SECONDARY EMISSIONS FROM FURNACE OPERATIONS (CHARGING,
SAMPLING, TAPPING)
When the vessel is tipped out from under the hood of the primary
control system, whether for charging, sampling, or discharging refined
steel, the traditional primary control system may be rendered ineffective.
Potential remedies range from enclosing the space around the vessel, through
specialized hoods, to building evacuation.
4.2.1 Furnace Enclosures
A furnace enclosure is a structure that may partially (on at least two
sides) or fully (on four sides plus top) enclose a furnace vessel. Most of
the BOPFs brought on stream in this country since 1973 are enclosed.2
A partial enclosure may be designed to shield the BOPF from most
drafts (other than that of natural convection), permitting hoods within or
adjacent to the enclosure to be more effective at lower airflow rates. In
addition, a partial enclosure is less expensive, easier to retrofit
(possibly without interrupting production), and less likely to impede
operations.
However, the trend is toward "total" enclosures.2 Figures 4-1 and 4-2
show such installations. Since the vessel is designed routinely to tilt
about only one horizontal axis, the enclosure can be fairly simple on two
sides. The enclosure roof is usually penetrated by the primary exhaust
4-2
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-is.
GO
Figure 4-1. BOP Furnace enclosure.
-------
Source: Republic Steel Corporation, South Chicago, Illinois
Shop floor
Figure 4-2.^ Furnace enclosure-for a Q-BOPF.
-------
duct, and it must be high enough for a closed system to permit maneuvering
the hood. Similarly, the flux chute and the oxygen lance of top-blown
vessels must penetrate either the roof of the enclosure or the primary
hood.
The enclosure can extend partially or completely to the operating
floor at the "rear," i.e., the side where tapping occurs, facing the teeming
aisle. Tapping is carried out at and below the level of the vessel, and
there is a tendency for hot, dusty gases to escape in the natural draft
induced by the process heat. It may be desirable to have a hood either
permanently arranged so that it does not interfere with operations, or
otherwise retractable to collect tapping emissions.
Most of the complications attending full enclosure arise in the
"front," i.e., the side at which charging is carried out, facing the
charging aisle. Here the enclosure includes a door or doors, turned or
rolled out of the way while charging scrap and hot metal. Since these
operations occur at and above the vessel, natural convection will permit a
plume of hot dusty gas to escape into the building. Figure 4-1 shows the
charging ladle mouth inside the furnace enclosure and under the charging
hood. If high fume capture efficiency is to be achieved, it is necessary
to design the ladle, scrap box, hood, furnace enclosure, and crane
facilities to allow the transfer to occur close to and under the hood.
This design also tends to minimize the air evacuation, rate required to
achieve high fume capture efficiency. Chain curtains can be used to
decrease the open area between the charging ladle and hood face and unlike
a rigid metal partition, are not subject to damage.
If the enclosure doors are to maintain their original fit, they must
not warp despite the difference between inside and outside temperatures.
This requirement suggests that the doors be of substantial construction and
generously insulated, water cooled,4 or both.
Figure 4-1 shows an opening at ground level on the charging side.
This openings permits entry and removal of a transfer car carrying the slag
pot into which the furnace slag is poured. The concept of total enclosure
requires that a vertical shield designed to close this opening be attached
to the transfer car.4 Because the environment is less severe here, this
shield can be portable and need not be as substantially constructed as the
doors.
-------
The "total" enclosure, then, is not truly total. The housing is
penetrated by ductwork and is opened and closed to permit access, and the
quality of closure is imperfect at best. However, the goal is not perfect
enclosure, but the substantial prevention of emissions to the building. As
such, if the "capture system" draws dusty air from inside the enclosure,
and if the enclosure and the exhaust system are compatibly designed and are
operated knowledgeably, the goal will be achieved.
The control system (capture plus particulate removal) may be an
extension of the primary control system. A hood designed to collect
charging emissions, and another for tapping emissions, could be ducted to
the primary system. Gas flows would be adjusted for the differing demands
of the several parts of the cycle.
In the closed hood system that intermittently handles a flammable gas,
use of the primary system to control dusty air from secondary sources
yields the possibility of an explosion. However, the facilities in at
least one shop have been designed to permit safe collection of secondary
emissions in the closed hood primary system.3
The more typical alternative is to duct the charging and tapping hoods
in the furnace enclosure to a secondary control unit, commonly a bag filter.
Such systems will be further described in following sections.
Furnace operations dictate the necessity for opening and closing the
doors on a furnace enclosure. For a total enclosure, charging of scrap and
hot metal to the furnace vessel requires the door(s) to be open.
Immediately following hot metal charge the door(s) may be closed. Since
observation of the vessel tops is important to the operator (visual feedback
on the occurrence of foaming and slopping over the vessel top), a television
picture or small observation port in the upper part of the enclosure can be
used to satisfy this need. As the oxygen blow is completed it is necessary
to take a metal sample and measure the metal temperature. In the United
States, most furnaces must be turned down to do this. Another opening in
the enclosure door may be provided to insert a thermocouple and sampling
spoon. Where such an opening has not been provided, it is necessary to
open the doors at last partially. This may cause poor control of furnace
emissions during the sampling period. Once open, the doors are often left
open for the remainder of the production cycle and generally poorer capture
of secondary furnace emissions can be expected. Nippon Steel in their Oita
4-6
-------
and Yawata Works use a sublance assembly to measure temperature and obtain
a metal sample.5 6 In a mannder similar to that for the oxygen lance, the
sublance is lowered into the furnace through a hole in the furnace
enclosure. This equipment avoids turndown for sampling, thus eliminating
potential secondary emissions.
Doors on the tapping side of the enclosure generally need not be
opened except for maintenance. Observation ports with closure flaps*can be
provided at required locations.
4.2.1.1 Kaiser Steel (Closed Hood. Top Blown). The Kaiser Steel
secondary emission control facility at Fontana, California, controls furnace
emissions (charging, tapping, puffing of the primary, turndown) plus hot
metal transfer and hot metal skimming.7 A schematic diagram of the
secondary system is presented in Figure 4-3. The furnace enclosure is
similar to that in Figure 4-1.
The secondary emission control facility has two fans each rated at
535,000 mVhr (315,000 ACFM) at 5 mm of water column and 230° C (450° F).8
Both fans operate to provide the baghouse design flow of 1,020,000 m3/h
(600,000 ACFM). Dampers are used to reduce gas flow and energy consumption
when full system flow is not required. Air flow is divided among the
various secondary hoods according to the needs for each operation. The
operations permitted to occur simultaneously depend on whether one or both
furnace vessels are being used. Based on design information, hot metal
charging requires the largest air flow, or about three-quarters of system
capacity. The Kaiser system does not permit hot metal transfer, hot metal
skimming, or a hot metal charge to the other vessel while one vessel is
being charged. The system does permit oxygen blow, turndown, tapping, or
deslagging on the second vessel when one vessel is being charged.
Hot metal transfer or hot metal skimming may occur at any time that
neither furnace is being charged. On this basis about one-third system
flow capacity is required for hot metal transfer or skimming.
The baghouse is a 12-compartment (2 cells each) positive pressure
installation with 33,400 m2 gross cloth area (360,058 ft2). The gross air
to cloth ratio is 0.533:1 m/min (1.75:1 ft/min) with a net air to cloth
ratio of 0.610:1 m/min (2.0:1 ft/min) when 3 cells are offline. Bag fabric
is fiberglass treated with silicon, graphite, and teflon. Bag cleaning is
performed by a reverse air system.
4-7
-------
Hot metal
transfer
1
V
Slag
skimming
1
Hot metal
transfer
2
\
Slag
' skimming
2
\
Furnace
charging hood
1
Furnace
charging hood
2
\ Tapping hood /
\ Tapping hood /
I 1
Baghouse
1,020,000 m3/hr
maximum temperature 230° C
Exhaust fans
Figure 4-3.
Schematic of. Kaiser Steel-Fontana Basic Oxygen secondary
emission control system..
4-8
-------
Performance of the secondary emission control facility at Kaiser has
been measured by visible emissions methods. Visible emissions measurements
of roof monitor discharges were made during April 1980.9
These measurements have been analyzed by two methods. Table 4-1
presents the results as analyzed according to EPA Method 9, i.e., 6-minute
average opacities based on observations made every 15 seconds. The table
shows the cumulative frequency distribution for 6-minute averages taken
each day. As is evident, none of the averages exceeded 15 percent opacity.
Table 4-2 presents the data analyzed on the basis of number of
individual opacity observations equal to or exceeding 20 percent opacity
for 21 production cycles. The data are broken down into segments of the
production cycle. It is evident from the table that turndown for sampling
produces the most numerous opacity excursions. These data for Kaiser Steel
represent single furnace operation.
4.2.1.2 Republic Steel, Chicago (Closed Hood, Bottom Blown). Only
three plants in the U.S. presently have bottom blown furnaces (Q-BOPF).
The two furnace vessels in the Republic Steel plant near Chicago have a
capacity of 205 tonnes. The secondary emissions system at this plant
includes full-furnace enclosures with charging hoods at the front of each
enclosure (Figure 4-2). There are no tapping hoods, and neither hot metal
transfer emissions nor hot metal skimming emissions are ducted to this
system. The Chicago shop is the best controlled bottom blown BOPF shop in
the United States. As of the summer of 1980 the other two bottom blown
shops were much less effectively controlled. U.S. Steel is installing a
secondary emission control system on one of the bottom blown BOPF vessels
at their Fairfield shop that has promise of surpassing the performance of
the Chicago system. The Fairfield modifications should be completed during
the first half of 1981.
The operations of the Q-BOPF during charging and turndown require gas
(either nitrogen or oxygen) to be blown through the tuyeres to prevent
liquid metal, slag, or solids from entering and clogging the tuyeres. This
factor makes capture of the secondary emissions more difficult than for top
blown furnaces.
Draft for the charging hood at the Republic plant is obtained from the
primary fume control system, as shown in Figure 4-4. Each furnace has its
own primary gas cleaning system; however, a crossover duct between the two
4-9
-------
TABLE 4-1. KAISER STEEL, FONTANA, CALIFORNIA9
Cumulative percent of 6-minute
averages less than or equal to
Date given opacity
0 5 10 15
4/7/80 85.0 98.5 99.8 100
4/8/80 60.1 93.2 99.4 100
4/9/80 87.3 100
4/10/80 89.1 99.3 100
4/11/80 97.9 98.7 100
Number of
individual
observations
1,683
2,310
2,161
1,583
1,549
4-10
-------
TABLE 4-2. KAISER STEEL TEST—NUMBER OF TIMES OPACITIES EQUAL TO OR
GREATER THAN TWENTY PERCENT WERE OBSERVED (> 20 PERCENT)9
Heat
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
Average
Charging
0
0
0
0
0
0
0
0
0
0
0
0
0
0
5
0
0
0
0
0
0
0.23
02 Blow*
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1:
T
1
1
1
1
1
0.9
Turndown
3
0
9
4
2
4
2
2
0
0
3
0
0
0
0
0
0
2
3
5
0
1.86
Tapping
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0.05
Total
3
0
10
5
3
5
3
3
1
1
4
1
1
1
6
1
1
4
4
6
1
3.04
Only 3 oxygen blow periods were read. One observation of opacity > 20 % is
assumed where no actual data were taken.
4-11
-------
Q-BOP-2
ro
SH
2
SO-2
SO-1
SH
1
Q-BOP-1
Q-2
BV-2
BV-1
Q-1
WS-2
WS-1
D-2
D-1
3.
3.
STACK 2
STACK 1
ABBREVIATIONS
Q-BOP = QUELLE-BASIC OXYGEN PROCESS FURNACE AND PECOR ENCLOSURE
PH = PRIMARY HOOD
SH - SECONDARY HOOD
SO - SHUTOFFVALVE
Q « QUENCHER
BV = BELL VALVE
WS - WET SCRUBBER (VENTURI)
D " DAMPER
F » INDUCED DRAFT FAN
Figure 4-4. Republic Steel Corporation's Q-BOP emission control system.
-------
furnaces permits the system for the nonoperating furnace to be used for
secondary emission control. With both gas cleaning system fans drafting
the charging hood, the flow rate is about 634,000 mVh (373,000 ACFM) at
93° C (200° F) during hot metal charging.10 During the oxygen blow, the
charging hood is drafted continuously through the scrubbing system of the
nonoperating vessel. During turndown and tapping, the charging hood is
drafted by the scrubbing system of the nonoperating vessel. Fume capture
during these latter operations is assisted by drafting the primary hood as
well. Fumes captured in the secondary (charging) hood bypass the quencher
and pass directly to the venturi in the scrubbing system. The design
pressure drop of the venturi during furnace charging is 218 cm (86 inches)
water column.
In general, the performance of the secondary emission control system
at Republic Steel was poorer than the best performing top blown secondary
systems. Data are available for two test series, June 1979, and June
1980.10 1:l These measurements have been analyzed by two methods. Table
4-3 presents the results of the data analyzed according to EPA Method 9,
i.e., 6-minute average opacities based on observations made every 15
seconds. The table shows the cumulative frequency distribution for 6-minute
averages taken each day.
No six-minute average opacity exceeded 45 percent during the tests at
Republic Steel. Only 3 of the 10 days during which observations were made
had no average opacities over 15 percent, as opposed to Kaiser where all 5
days had no average opacities over 15 percent.
Table 4-4 presents the same data analyzed on the basis of number of
individual opacity observations equal to or exceeding 20 percent opacity
for 27 production cycles. The data are broken down into segments of the
production cycle.
When examining performance on the basis of individual cycles, it is
evident that performance is characterized by extremes. There is a group of
cycles with 0 to 6 excursions equal to or greater than 20 percent, a group
of cycles with 19 to 36 excursions, and none in-between. Specific causes
for this large variation have not been identified. The data also show that
in many of the production cycles with a high number of total excursions,
each of the cycle segments contributes to the overall high emissions rather
than just one segment. -Tapping, however, appears to produce more excursions
than the other cycle segments.
4-13
-------
TABLE 4-3. REPUBLIC STEEL, CHICAGO, ILLINOIS10
Cumulative percent of 6-minute averages less than
Date or equal to given opacity
0 5 10 15 20 25 30 35
Number of
individual
observations
40 45
6/18/79 10.3 33.5 53.1 73.7 88.6 96.4 98.3 100
1,363
6/19/79 54.6 94.3 99.0 100
6/20/79 54.4 95.9 100
6/21/79 42.2 90.0 93.1 97.2 97.9 98.7 98.9 99.3 100
6/22/79 13.5 67.8 81.8 90.3 96.6 97.3 98.8 100
1,819
1,901
1,670
588
6/2/80 61.8 96.6 97.2 98.2 99.2 99.7 100
1,241
6/3/80 21.1 53.3 75.6 86.1 95.8 98.3 99.4 100
1,765
6/4/80 64.1 96.8 99.6 100
2,448
6/5/80 52.7 79.7 86.8 91.3 94.1 97.2 98.9 99.5 99.8 100 5,675
6/6/80 24.4 80.3 95.1 99.8 100
1,174
4-14
-------
TABLE 4-4. REPUBLIC STEEL Q-BOP TEST—NUMBER OF TIMES OPACITIES EQUAL
TO OR GREATER THAN TWENTY PERCENT WERE OBSERVED (> 20 PERCENT)10 "
Heat
1
2
3
4
5
Charging
1
3
6
11
0
Qy BlOW
0
0
5
0
0
Turndown
1980 Test
4
0
6
7
0
Tapping
0
0
19
17
1
Total
5
3
36
35
1
Average 4.20 1.0 3.40 7.40 16.00
1979 Test
1 12 11 0 3 26
2 13 5 12 5 35
3 6 0 13 0 19
4 8 14 0 10 32
5001 01
6006 06
7300 03
8000 00
9001 01
10 2 0 0 02
11 0 3 0 0 3
12 0 0 0 00
13 0 0 0 00
14 0 0 0 00
15 0 0 4 04
16 0 o 14 16 30
17 0 0 0 88
18 0 0 2 02
19 0 0 2 02
20 0 0 0 00
21 0 3 17 11 31
22 0 0 4 21 25
Average 2.00 1.64 3.45 3.36 10.45
4-15
-------
During the 1979 tests it was noted that leakage occurring on the
tapping side of the furnace enclosure contributed to tapping fugitive
emissions.10 The addition of a separate tapping side hood to the enclosure
might improve overall system performance.
4.2.1.3 Republic Steel, Cleveland, Ohio. This BOPF shop is equipped
with two 250 tonne furnace vessels. The primary gas cleaning systems for
these furnaces are closed hood type (IRS1D-CAFL) with venturi scrubbers.
The shop originally had open hood systems with electrostatic precipitators,
but was converted to closed hood design in 1976-1977.
At the time of the conversion a secondary emissions control system was
also installed. A furnace enclosure (completely enclosed at operating
floor level) was built around each furnace. Local charging and tapping
hoods were constructed at each enclosure. Scavenging hoods were also added
in the charging aisle above each furnace to provide additional capture of
secondary emissions. In addition to these provisions for secondary furnace
emissions, the system collects fumes at teeming ladle nozzle lancing
stations, hot metal transfer, and dust from the ladle additive material
handling operations (Figure 4-5). Gas cleaning is provided by the
electrostatic precipitator originally installed to treat primary emissions.
The design air flow evacuation rate for the scavenger hood is 2,830
mVmin (100,000 ACFM) at 38° C (100° F).12 The plant presently does not
use the scavenger hood, but there is an unknown amount of leakage through
the louver damper. The evacuation rate through the charging hood is about
8,500 nrVmin (300,000 ACFM) at 38° C (100° F).17 During tests performed at
the plant in 1979 with all other system dampers closed, the charging hood
evacuation rate was measured to be 10,136 dry standard nrVmin
(357,800 DSCFM).13 During the same test series the tapping hood evacuation
rate was measured to be 9,085 dry standard nrVmin (320,700 DSCFM).
Emissions from the hot metal transfer station are captured by a side
draft local hood with a canopy-like flange covering the torpedo car opening,
The design evacuation rate for this operation is 4,250 mVmin (150,000
ACFM) at 110° C (230° F).
Visible emissions observations were made at this plant during
June 1980.19 As in the case of the other plants tested, the data were
compiled into 6-minute averages as required by EPA Method 9 and into
occurrences of emissions equal to or greater than 20 percent opacity.
These data compilations are shown in Tables 4-5 and 4-6, respectively.
4-16
-------
NORTH TEEMING
LADLE NOZZLE LADLE ADDITIVE
LANCING STATION AND OUST COLLEC-
TION
1
*. * * t * » * *
ELECTRO- I I I -I I I I I
ssk '*y**!*[A!*
TATORS A A 6
LADLE ADDITIVE AND DUST
COLLECTION (BIN)
VENT FAN
INLET
SAMPLING
SITE
TAPPING HOOD
/VESSELS
1 No. 2 J
CHARGING HOOD
SCAVENGER HOOD
LADLE ADDITIVE AND
DUST COLLECTION (CHUTES)
SOUTH TEEMING
LADLE NOZZLE
LANCING STATION
NEW AND EXISTING
MULTICLONES
6
POURING HOOD
EXIST. STATION
Figure 4-5. Republic Steel Corporation, Cleveland, Ohio, BOPF secondary emission control system
schematic.
-------
TABLE 4-5. REPUBLIC STEEL CORPORATION, CLEVELAND, OHIO14
Number of
Cumulative percent of 6-minute averages less than individual
Date or equal to given opacity observations
0 5 10 15 20 25 30 35 40 45 50 55 60
6/10/80 56.3 95.6 96.9 100 1,308
6/11/80 48.1 80.0 91.4 95.6 97.4 100 1,448
6/12/80 53.8 81.7 93.7 98.3 99.4 100 1,432
6/13/80 32.2 70.5 85.7 93.0 94.8 95.4 96.1 96.8 97.6 98.1 99.0 99.4 100 1,440
4-18
-------
TABLE 4-6. REPUBLIC STEEL TEST (CLEVELAND)—NUMBER OF TIMES OPACITIES
EQUAL TO OR GREATER THAN TWENTY PERCENT WERE OBSERVED (> 20 PERCENT)14
Heat Charging 02 Blow Turndown Tapping Total
DATA NOT CURRENT AVAILABLE
4-19
-------
Only one day of the four test days produced no 6-minute opacities
exceeding 15 percent. Two days were in the 20 to 25 percent opacity range.
One day produced readings in the 50 to 60 percent opacity range. Based on
process data the high opacity readings on June 13 occurred when
desulfurization of a hot metal ladle in an uncontrolled auxiliary pit and
furnace tapping occurred simultaneously.
On June 11 and June 12, readings in the 15 to 25 percent opacity range
occurred during varied furnace operations. Some were attributable to hot
metal charging, some to puffing caused by slopping in the furnace, and some
to turndown.
In general, the overall visible discharges from the Cleveland shop may
be expected to be higher and more frequent because of the use of an
auxiliary pit with no hood (for hot metal transfer and desulfurization) and
due to many leaks in the furnace enclosure. Leaks from the lance hole, the
ladle addition chutes, and the observation ports in the tapping side of the
furnace contribute to roof monitor visible emissions. As shown the
Cleveland system is not as effective as the Kaiser system. This is
attributable to the foregoing factors and the lower Cleveland exhaust
ventilation rates (300,000 ACFM at Cleveland versus a maximum of 600,000
ACFM at Kaiser).
4.2.2 Local Hoods
Hooding is a common method for capturing particulate emissions from
scattered sources in a plant. Design of hoods for BOPF secondary emissions
is complicated by cross drafts that develop within the building interfering
with fume capture. A hood located close to the source, and intended to
reduce cross drafts, may get in the way of crane operations. Every design
is a compromise.
The design of a hood, a duct, a fabric filter, and an exhaust fan to
handle a specified volume of air is routine. The temporal variation in
average temperature and dust loading can cause mild fluctuations in volume,
which can be accommodated by modest overdesign. It is more difficult to
predict the source of the air that flows into the hood, unless the hood
fits closely around the source. However, close fitting can interfere with
the batch operations of the process. If the hood is positioned so as not
to interfere, and the system is undersized, part of the rising plume may
4-20
-------
escape on one side while clean air is drawn in on the other. Cross drafts
are unpredictable; sheet-metal barriers may be erected to diminish their
effect. If the hood is to capture the plume consistently, a remedy is
over-design or a "factor of safety." The degree of excess capacity in a
system cannot be known until it is operated under a variety of climatic and
production conditions.
Apart from the emissions that are collected regularly at fixed
locations, certain necessary maintenance operations generate dust less
susceptible to collection by local hoods. For example, when it is necessary
to reline a ladle, it will be allowed to cool; after dislodging the
refractory lining the ladle will be turned upside down and dumped into a
truck or onto the shop floor.
Local hoods exhausting to a secondary system are only part of the
secondary emission control system. The best systems observed exhaust the
several local hoods to a single baghouse, using interlocks and status
lights to insure that the full air-moving power of the system is devoted to
only a few tasks at any one time.7 15
4.2.3 Canopy or Roof Hoods, Partial Building Evacuation
Buildings to cover hot operations like glass melting, synthetic
graphite production, and BOPFs exploit natural convection for operator
comfort. The heated air rises and exits through roof openings (roof
monitors) with covers that prevent rain from falling on the furnaces. Fine
particles can be entrained in this rising air and, exit through the
monitors.
The canopy hood is one answer for some emissions that either have not
been provided for or that inevitably escape the local hoods described in
Section 4.2.2. To the degree that the source is concentrated in one area
of the building, but not so concentrated as to permit local hooding of the
desired capture efficiency, there will be a relatively concentrated plume
of hot dusty gas rising from that area. A canopy hood will not interfere
with operations, can collect the fine, entrained particulate at relatively
low velocities, and can be ducted continuously to a collecting device.
There are disadvantages to canopy hoods. Cross drafts in the shop can
displace rising fume so that it evades the hood, or the rising plume may
expand and diffuse to dimensions larger than the hood face. The canopy
hood system adds a significantly larger gas volume to be cleaned. When
4-21
-------
added to an existing system, canopy hoods may reduce draft in the rest of
the system to the point that air velocity in the other hoods is too low to
capture fume effectively.
One means of reducing the impact of cross drafts and avoiding the
problem of the plume's becoming larger than the hood face dimensions is to
use partial building evacuation. The building structure, in essence,
becomes the hood for a particular part of the operation. Partition walls
may be installed between building columns to prevent lateral movement of
the plume into adjacent portions of the building. These partition walls
may be extended as low in elevation as crane operations will permit, and
extend all the way up to the roof. Sheeting or partitions are also used to
seal the roof area to prevent the escape of emissions by natural thermal
draft. One or more duct connections are made into the sealed portion of
the building to extract contaminated air for gas cleaning.
A further variation of this approach is available by altering the
choice of gas cleaning device. Instead of ducting contaminated air away to
a remote collector, the collector may be erected immediately above the
enclosed roof area. At least three companies presently offer roof-mounted
electrostatic precipitators that take advantage of the natural thermal
drafts above the hot processes. However, none are installed in United
States BOPF shops. Since precipitators are characteristically low pressure
drop devices, the thermal draft assist means little or no fan power is
required to move contaminated air through the collector. Additional
information concerning roof-mounted collectors will be presented later in
this chapter.
4.2.3.1 Inland Steel, East Chicago, Indiana (Closed hood, top blown).
The No. 2 BOPF shop at Inland Steel's East Chicago plant contains two
195-tonne capacity top blown furnace vessels. The primary gas cleaning
system is a closed hood type with venturi scrubbers.
There are two principal secondary emissions control systems in this
plant. One system treats furnace emissions captured in local hoods located
in the partial furnace enclosure. The second system cleans emissions
captured by partial building evacuation and emissions from local hoods at
the hot metal transfer and hot metal skimming stations.
Local hoods within the partial furnace enclosure include a charging
hood, tapping hood, and a wrap-around hood (at the side of the furnace) to
4-22
-------
capture puffing emissions during the oxygen blow.16 During charging, only
the charging hood is drafted; during tapping, the tapping hood and
wrap-around hoods are drafted. While oxygen blowing is occurring all three
hoods are drafted. Air flow for the furnace enclosure secondary emission
system is induced through a venturi scrubber by a fan rated for 3700 m3/min
(131,000 ACFM) at 21° C (70° F).16 Overall system pressure drop is 130 cm
(51 in.) water column. Since this evacuation rate is not sufficient to
capture all charging and furnace deslagging emissions, the partial building
evacuation system provides additional capture of these emissions.
The partial building evacuation system is applied only to the furnace
charging aisle. There is a curtain wall between the charging aisle and
furnace aisle to prevent substantial movement of charging emissions into
the uncontrolled furnace aisle. There are two duct takeoffs in the charging
aisle roof, one centered above each furnace. A damper is provided in each
takeoff to open or close it as necessary. During hot metal charging and
furnace deslagging the damper is opened to maximize the evacuation rate
above the affected furnace.
The total air flow capacity for this partial building evacuation hot
metal handling secondary emissions system is 11,330 mVmin (400,000 ACFM)
at 135° C (275° F). Flow is divided between partial building evacuation
and hot metal handling, with 7,790 m3/min allotted to the roof ventilation
system and 3,540 nrVmin to the hot metal station. The available system
pressure drop is 38 cm (15 in.) water column and gas cleaning is provided
by a baghouse.
Roof level visible emissions observations were made at this plant
during May I960.17 These measurements were analyzed on the same basis as
the Kaiser Steel data, i.e., 6-minute average opacities were calculated
according to Method 9 procedures and the number of excursions equal to or
greater than 20 percent opacity was determined. Table 4-7 presents the
6-minute average opacities for five days and Table 4-8 presents the number
of excursions for six production cycles.
The data in Table 4-7 show that on three of the five days the 6-minute
average opacities were as good as those observed during the Kaiser Steel
tests. On one of the remaining two days there were several readings in the
15 to 20 percent range, but none over 20 percent. On May 15, 6-minute
averages in the 35 to 40 percent range were observed.
4-23
-------
TABLE 4-7. INLAND STEEL, EAST CHICAGO, INDIANA17
Number of
Cumulative percent of 6-'minute averages less than individual
Date or equal to given opacity observations
0 5 10 15 20 25 30 35 40 45
5/12/80 44.1 79.2 89.6 98.8 100 479
5/13/80 83.6 100 1,373
5/14/80 40.0 88.4 100 1,504
5/15/80 22.2 66.2 83.6 89.6 94.7 97.3 98.4 98.9 99.9 100 1,460
5/16/80 97.2 100 963
4-24
-------
TABLE 4-8. INLAND STEEL TEST—NUMBER OF TIMES OPACITIES EQUAL TO OR
GREATER THAN TWENTY PERCENT WERE OBSERVED (> 20 PERCENT)17
Heat
1
2
3
4
5
6
Average
Chargi ng
0
0
0
16
0
0
2.7
02 Blow
2
2
0
29
0
0
5.5
Turndown
0
0
0
10
0
0
1.7
Tapping
0
0
0
1
0
0
0.17
Total
2
2
0
56
0
0
10
4-25
-------
In five of the six production cycles for which excursions > 20 percent
opacity could be determined (Table 4-8), the number of excursions per cycle
was two or less. On May 15 for one production cycle 56 excursions were
observed. No specific process or control equipment upset has been
identified to be the cause of the higher opacity observations on May 15.
The general trend shown by both methods of analyzing the data is that the
poorer performance was evident throughout the observations on May 15, not
confined to one short period of the day.17
Comparison of the Kaiser and Inland data show that the Kaiser secondary
control system is more effective. This may be due to the lower exhaust
ventilation rates at the Inland shop or differences between the
effectiveness of the fume capture systems. However, the data do not show
that canopy or roof hoods are incapable of controlling secondary BOPF
particulates as effectively as furnace enclosures. All the data shows is
that the Inland system as currently designed is not as effective as the
Kaiser system.
4.2.4 Building Evacuation
Extension of the canopy hood concept leads to building evacuation. In
effect, the entire building becomes a hood. Although building evacuation
seems the most certain way of completely capturing all secondary emissions,
there are disadvantages. Exhausting the air at a sufficient rate for
building evacuation requires a system gas flow larger than that described
for local hoods, consequently costs are greater. Since fan work is
proportional to the product of pressure drop (Ap) and flow rate, and given
the same type of collector (fabric filter) for both local hooding and
building evacuation, the energy expenditures will be higher for the building
evacuation system. Particulate emissions from BOPF shops equipped for
building evacuation could also be greater than particulate emissions from
shops equipped with furnace enclosures or hoods. This is because there is
no assurance that the concentration of particulate emissions from a baghouse
would be lower for building evacuation than for hoods or furnace enclosures.
At equal concentrations emissions from a building evacuation baghouse would
be greater because of the larger exhaust volumes. As discussed in Section
4.4.1 there is not enough data to support a lower limit for building
evacuation baghouses than for furnace enclosures or local hood baghouses.
4-26
-------
There are no total building evacuation systems applied to BOPF shops
in the United States. There are several such systems in use for other
types of steelmaking, particularly electric arc steelmaking and ADD
steel making. Three of the plants that use these systems produce alloy and
stainless steel.
Babcock and Wilcox in Beaver Falls, Pennsylvania, operates two
plants --Wallace Run and Koppel. The Wallace Run plant has one shop with
two 22.7 tonne electric arc furnaces (EAF) and another shop with a 45.5 and
68.2 tonne EAF. The Koppel plant has a 45.5, 68.2, and three 90.9 tonne
EAFs. The design building evacuation rates at Wallace Run are 6,515 and
13,030 nrVmin, respectively, for the small and large shops. Total design
evacuation rate for the Koppel plant is 52,120 nrVmin.18 The Koppel plant
system is designed to provide one air change every 2.5 minutes. Design gas
temperature for all these systems is about 100° C.
To achieve satisfactory air movement through the buildings, ventilation
openings (to supply and distribute incoming air) were added and changed.
At some locations partition walls (curtains) were installed on building
columns to reduce travel of fume into adjacent areas. Roof monitors were
sealed and duct takeoffs installed in the roof above the furnaces.18
In both of the plants, the fume capture systems are connected to bag-
houses. Details of the collector design are discussed in a later section
of this chapter.
Crucible Steel at Midland, Pennsylvania, operates an EAF and AOD
(argon-oxygen decarburizer) facility to produce alloy and stainless steel.
There are 4 EAFs each with 81.8 tonne capacity and one AOD vessel with 90.9
tonne capacity. Duct takeoffs for the evacuation system are in the roof of
the building. The evacuation rate for the whole building is 50,400 mVmin
(1,800,000 ACFM) at a design temperature of 121° C (250° F).19 The fume
collection system for this plant is a baghouse. Recovered dust contains
chrome and nickel because of the stainless alloying process; the dust is
recycled. Additional data on baghouse design are presented in a later
section of this chapter.
4.2.5 Other Systems
A literature survey conducted for EPA in 1977 found descriptions of
eight control systems for charging emissions at BOPFs in this country.20
4-27
-------
Seven consisted of auxiliary hoods connected to open hood primary systems,
as outlined in Section 4.2.1. Use of an open hood primary control system
to capture secondary emissions from furnace charging and tapping is made
feasible because of the large gas evacuation rate associated with open hood
systems. Gas evacuation rates for open hood systems may be four times
larger or more than those of closed hood systems.
The other factor that assists success of this approach is that charging
fume generation can be reduced by adoption of certain operating practices.
Use of clean scrap (non-oil bearing, non-galvanized), slow pouring of hot
metal into the furnace, and careful positioning of the hot metal ladle with
respect to the hood face and furnace mouth, are all means of reducing
charging emissions.
Bethlehem Steel uses its primary system for secondary emissions control
in its Bethlehem, Pennsylvania, plant. More descriptive information and
performance test results are presented later in this section.
The eighth control system identified in the EPA literature survey was
the patented Gaw damper.21 This damper is placed at the inlet (face) of
the open hood primary system and is used to reduce the open area of the
hood face during charging and tapping. The opening is constricted to
increase hood face velocity and direct hood suction to the side of the hood
nearest the charging or tapping operation. The relationship among gas
properties, fan performance, system resistance, and total volumetric flow
rate is complex . To design such a system for specified performance during
charging and to adjust it after installation is difficult since emissions
from one charge to the next are quite variable. Perhaps for these reasons
the industry has not widely adopted the Gaw damper. Engineers from National
Steel, who studied the device as applied to a 1-ton pilot furnace, gave it
a favorable report, but anticipated that there might be maintenance problems
at full scale.20 Republic Steel at Gadsden, Alabama, has retrofit two
furnace hoods with Gaw dampers.22 More details on this facility are
presented later in this section.
The same pilot study described charging through a "launder," i.e., a
refractory-lined chute built through the hood.20 Since the vessel did not
have to be tipped for charging, emissions were collected by the primary
system. This scheme worked well but apparently has not been commercialized.
4-28
-------
4.2.5.1 Bethlehem Steel, Bethlehem, Pennsylvania. This BOPF shop
contains two 272 tonne furnaces with an open hood type primary gas cleaning
system. Each furnace is partially enclosed by side walls, with no enclosure
on the charging or tapping sides. An awning has been constructed on the
tapping side between the side enclosures that extends toward the teeming
aisle as shown in Figure 4-6. This awning acts as a flanged extension of
the primary hood and helps direct tapping fumes into the primary hood.
There is also an extension from the primary hood on the charging side of
the furnace.
During hot metal charging operations the gas evacuation rate for the
primary hood is 14,160 nrVmin (500,000 ACFM) at about 82° C (180° F).23 24
The initial portion of the hot metal charge is performed with the furnace
mouth tipped only partially out from under the hood. As the charge nears
completion the furnace is turned further bringing out the entire mouth.
Fume escape is worst at the end of the charge. During the oxygen blow the
primary hood evacuation rate is about 21,200 mVmin (750,000 ACFM) at a
temperature of 210° C (420° F).23 24 When the vessel is turned down for
tapping or other reasons the evacuation rate is 14,160 m3/min (500,000 ACFM)
at about 82° C (180° F).23 24
The primary and secondary gas cleaning device for this BOPF shop is an
electrostatic precipitator. A dropout chamber precedes six horizontal dry
precipitators operating in parallel.
Roof monitor visible emissions observations were performed at this
plant in June 1980.?5 These measurements were analyzed by two methods.
Table 4-9 presents the results as analyzed according to EPA Method 9, i.e.,
6-minute average opacities based on observations made every 15 seconds.
The table shows that no 6-minute average opacity exceeded 5 percent on the
four test days.
Table 4-10 presents the data analyzed on the basis of number of
individual opacity observations equal to or exceeding 20 percent opacity
for eleven production cycles. The data are broken down into segments of
the production cycle. The table shows that the maximum number of excursions
equal to or greater than 20 percent opacity for eleven production cycles
was two.
All these data for Bethlehem Steel represent single furnace operation.
In addition to furnace operations, slag pot dumping, ladle deskulling, hot
metal transfer, and teeming occurred during these tests.
4-29
-------
UO——UO
Figure 4-6.
Bethlehem Steel, Bethlehem, Pennsylvania-BOPF partial furnace
enclosure for open primary hood.
4-30
-------
TABLE 4-9. BETHLEHEM STEEL, BETHLEHEM, PENNSYLVANIA25
Date
Cumulative percent of 6-minute
averages less than or equal to
given opacity
0 5
Number of
individual
observations
6/23/80
6/24/80
6/25/80
6/26/80
80.6
93.9
96.3
81.4
100
100
100
100
1,413
1,920
1,920
1,811
4-31
-------
TABLE 4-10. BETHLEHEM STEEL, BETHLEHEM, PENNSYLVANIA—NUMBER OF TIMES
OPACITIES EQUAL TO OR GREATER THAN TWENTY PERCENT WERE OBSERVED
(> 20 PERCENT)25
Heat
1
2
3
4
5
6
7
8
9
10
11
Average
Charging
1
0
0
0
0
0
0
0
0
0
0
0.09
02 Blow
0
0
0
0
0
0
0
0
0
0
0
0
Turndown
Oa
0
0
0
0
2
0
0
0
0
0
0.18
Tapping
ob
ob
oc
0
0
0
0
0
0
0
0
0
Total
1
0
0
0
0
2
0
0
0
0
0
0.27
a.. ,.r ......
.No VE taken during turndown, zero assumed.
cNo VE taken during tapping, but VE taken during deslagging, zero assumed.
VE taken during tapping, but not deslagging, zero assumed.
4-32
-------
A significant portion of the performance achieved at the Bethlehem
plant must be attributed to good operating practice and skillful crane,and
furnace maneuvering. The plant is missing the benefits of full furnace
enclosure and the advantage of local hoods closer to and immediately above
the fume sources found in new plants. The effectiveness of secondary
emission control at the Bethlehem shop is superior to the effectiveness of
the Kaiser system. However, the techniques employed at Bethlehem are not
applicable to all BOPF shops. The Bethlehem shop vessels are equipped with
open hoods while most modern BOPF vessels are of closed hood design. In
addition it is not demonstrated that the careful operating techniques
employed at Bethlehem to limit secondary emissions could be universally
implemented.
4.2.5.2 Republic Steel, Gadsden, Alabama.22 This BOPF shop contains
two 136 tonne furnace vessels with open hood primary gas cleaning
facilities. No furnace enclosures, either full or partial are in use. Gaw
dampers are installed under the face of the combustion hoods for each
furnace as shown in Figure 4-7. Figure 4-8 is an illustration of the
provision for tapping emission control—a canopy to prevent loss of fume
into the teeming aisle. Emissions are drawn back into the primary system
hood.
The Gaw damper in Figure 4-7 actually closes about 50 percent of the
primary hood face area during hot metal charging. It does not serve a
similar function during tapping. The gas evacuation rate during hot metal
charging is about 17,000 m3/min (600,000 ACFM) at a temperature of about
77° C (170° F). A reduced evacuation rate, about 9,900 mVmin (350,000
ACFM) at 77° C, is used during tapping, deslagging, and other turndowns.22
Visible emissions data were gathered at this plant in August 1979.22
Roof monitor opacities were read during forty-two furnace production cycles.
These data have been analyzed on the same basis used previously in this
chapter, i.e., 6-minute averages and excursions equal or greater than 20
percent. Tables 4-11 and 4-12 present the results of the respective data
analyses.
The data in Table 4-11 show that 6-minute average opacities are not as
low as those encountered at Kaiser Steel and Bethlehem Steel. The data
analysis presented in Table 4-12 shows, however, that the main problem with
emissions occurs during the oxygen blow rather than during hot metal
4-33
-------
Exhaust hood
Charging
ladle
Service floor
Closure plate
park position
150 ton vessel
Source: Republic Steel Corporation.
Figure 4-7. Gaw damper position during hot metal charging at RSC/Gadsden.22
4-34
-------
Exhaust hood
Charging
aisle
Service floor
Closure plate
park position
Fume canopy
Teeming
aisle
150 ton vessel
Source: Republic Steel Corporation.
Figure 4-8. Tapping emission control at RSC/Gadsden.
4-35
22
-------
TABLE 4-11. REPUBLIC STEEL, GADSDEN, ALABAMA22
Number of
Cumulative percent of 6-'minute averages less than individual
Date or equal to given opacity observations
0 5 10 15 20 25 30 35 40 45
8/20/79 60.5 94.4 97.2 98.2 99.1 100 1,992
8/21/79 52.6 90.0 96.2 98.3 99.5 99.7 100 2,002
8/22/79 40.9 84.7 90.0 95.1 97.9 98.8 98.9 99.1 99.2 100 2,344
8/23/79 48.9 94.3 97.1 99.3 100 1,860
4-36
-------
TABLE 4-12. REPUBLIC STEEL TEST (GADSDEN)—NUMBER OF TIMES OPACITIES
EQUAL TO OR GREATER THAN TWENTY PERCENT WERE OBSERVED (> 20 PERCENT)22
Heat
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
Charging
3
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
7
0
0
0
0
0
0
0
10
0
0
0
0
0
0
0
0
0
0
0
0
02 Blow
0
0
0
11
13
0
0
0
0
1
0
8
1
0
4
10
7
10
0
0
0
27
9
10
0
0
3
38
19
0
0
0
0
5
0
6
0
0
0
10
0
0
Turndown
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Tapping
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Total
3
0
0
n
13
0
0
0
0
1
0
8
1
0
4
10
7
10
0
0
0
34
9
10
0
0
3
39
19
10
0
0
0
5
0
6
0
0
0
10
0
0
Average 0.48 4.57 0 0.02 5.07
4-37
-------
charging. Process observations obtained during the tests reveal that the
principal reasons for visible emissions during the oxygen blow were leakage
through the oxygen lance hole, leakage from the primary hood, and a lower
(10 percent) primary system gas evacuation for one furnace as opposed to
the other.22 The referenced report concludes that the Gaw damper
effectively controlled hot metal charging emissions (its intended purpose).
Table 4-12 shows the average number of excursions equal to or greater
than 20 percent opacity were about five per production cycle. The maximum
number was 39 with most of the high number of excursions due to problems
during the oxygen blow. The data show that the Gadsden Gaw damper system
is not as effective as the Kaiser furnace enclosure. This is because the
design of the hood system allows more particulate to escape.
4.2.5.3 Foreign Installations. Other BOPF secondary emission control
systems in use outside the U.S. have been seen to produce performance
comparable to the facility at Kaiser Steel.15 No official visible emissions
observations have been performed on these systems, however. Specifically,
the Oita and Yawata Works of Nippon Steel are examples of well controlled
BOPF facilities in Japan.5 6 The Taranto Works of Italsider in Taranto,
Italy is also in this category.26 All of these plants depend on furnace
enclosures and local hooding to capture furnace emissions. Local hooding
is also applied to other secondary emissions sources in these plants, i.e.,
hot metal transfer, hot metal skimming, ladle deskulling, external
desulfurization of hot metal, steel transfer to tundish for continuous
casting.
At least one foreign installation with partial building evacuation has
been observed to control visible emissions from secondary emissions
relatively well. The Chiba Works of Kawasaki Steel has a relatively new
Q-BOP shop. The No. 3 shop has two 230 tonne bottom blown furnaces. This
plant was constructed with furnace enclosures including charging hoods
inside the enclosures, and roof-mounted electrostatic precipitators to
collect furnace emissions that escape during hot metal charging as shown in
Figure 4-9.15 One precipitator is located above each furnace. The design
gas flow rate for each is 13,500 irrVmin (477,000 ACFM).27 The total gas
flow in the secondary system for the local hoods is 18,000 mVmin (635,400
ACFM). This latter capacity is shared with other secondary sources
including raw materials handling, torpedo car desulfurization, hot metal
transfer, and hot metal skimming.
4-38
-------
Flare stack
for primary system
Secondary
system stack
• To gas recovery
Figure 4-9.
Kawasaki-Chiba Works plant arrangement with partial building
evacuation.
4-39
-------
4.3 CONTROL OF SECONDARY EMISSIONS FROM ANCILLARY OPERATIONS (HOT METAL
TRANSFER AND SKIMMING)
Given the trend to enclosed BOPFs the emissions from charging,
sampling, and tapping are closely associated with the vessel and their
control must be integrated with the design of the enclosure. Charging,
sampling, and tapping do not occur during blowing, so the integration of
these operations with a primary furnace control system is at least feasible.
However, the ancillary operations of hot metal transfer and hot metal
skimming take place at various times and distances from the furnace. The
integration of their control with that of the other operations would be
awkward both structurally and operationally. Therefore, the trend has been
to a separate secondary control system.
Local hoods are the principal choice for capture of emissions from hot
metal transfer and hot metal skimming. Hoods placed above the source are
more effective than those attempting to capture the hot emissions with side
draft.
4.3.1 Kaiser Steel, Fontana, California.7
Kaiser Steel performs hot metal transfer and ladle deslagging
(skimming) at one side of the BOPF shop where there are two stations. A
shed or lean-to is built onto the side of the main building as shown in
Figure 4-10. Torpedo cars are moved into the shed on tracks passing through
the shed. Chain curtains hanging from the top of each entrance help to
restrict the opening size and reduce required draft. The torpedo car pours
hot metal through a slot into a shop ladle sitting on a transfer car below
ground level. Upon completion of the hot metal transfer, the transfer car
moves under an adjacent hood in the same station where slag is raked off
the metal surface while the ladle is tilted. Both hoods in the station are
evacuated through the same duct. Draft is apportioned between the two
hoods by means of dampers located at the duct entrance above the station.
Operation of the system in conjunction with the furnace enclosure
hoods is discussed in Section 4.2.1.1. The estimated gas evacuation rate
during hot metal transfer and skimming is about one-third system capacity
or 4,670 m3/min (200,000 ACFM).8 Tests at Kaiser, Fontana showed that the
hood system captures virtually all of the particulates from hot metal
transfer and skimming.
4-40
-------
Exhaust to
baghousa
Figure 4-10. Kaiser Steel hot metal transfer and skimming station.
4-41
-------
4.4 PARTICULATE CONTROL DEVICES
The dominant feature of the particles arising in the several steps of
the basic oxygen process is their size. The size distributions for some
secondary emissions are presented in Table 3-6 The finest particles are
believed to be formed by condensation, the quenching of vaporized iron when
it contacts combustion air at the mouth of the vessel. Mixed with these
fine particles of condensed iron oxide in the secondary emissions are
graphite or "kish" formed from carbon present in molten iron. If not
collected, these emissions, particularly the iron fume, are carried by
natural convection up to and out of the roof monitor. If these rising
velocities are in the range 0.3 to 3.0 m/s28 (1 to 10 ft/sec), and the
particles have specific gravities near five, then sizes up to 200 microns
could be lifted.29 When the plume mixes with cooler air and slows somewhat
before accelerating through the constriction imposed by the roof monitor,
there may be opportunity for particles larger than perhaps 40 microns to
"rain out"; but the smaller fume is entrained.
Devices suitable for the collection of such fine solids with 98 percent
or higher efficiency are the fabric filter, the high performance wet
scrubber, and the electrostatic precipitator. Fabric filters have found
widest use of the three types in BOPF secondary emission control.15 In
fact, these three devices can be designed with such efficiencies that the
limitation in overall performance traces to the hood rather than the control
device.
4.4.1 The Fabric Filter.
This control device has been amply described in previous EPA
documents30 31 and vendors' literature. Only a brief summary is appropriate
here. The fume, after capture at the hood and transport through a duct,
comes to the fabric filter. The interstices between the fibers in a woven
or felted bag are partially blocked by particles not removed during the
last cleaning operation, and ordinarily a coating or "cake" of particles is
deposited on the fabric. The gas can penetrate the cake and the underlying
fabric, but few particles can pass through an undamaged fabric with a cake
deposited on it. The collection efficiency can be very high (> 99 percent)
if damaged fabric is promptly replaced.
4-42
-------
The preferred geometry is multiple cylindrical fabric bags disposed in
several independent compartments to permit cleaning and maintenance. As
the dusty air is filtered, the cake builds up and the pressure drop
increases. On a predetermined schedule, or when the pressure drop across a
compartment has risen to a predetermined level, the bags in that compartment
are cleaned mechanically or pneumatically, although never to their original
condition. The solids thus collected drop into a hopper. If the solids
are abrasive or if cleaning is too frequent or vigorous, bag life is
shortened; frequent bag failure is expensive and reduces the average
collection efficiency. For similar reasons the dust should not approach a
freshly cleaned bag too fast; this maximum "face velocity" or "air-to-cloth
ratio" for iron oxide is said to be about 0.61 m/min (2 ft/min).30 Current
bag materials and cleaning methods may have modified this figure somewhat.
Taken together with the desired exhaust volume and the specified excess
capacity, this rule of thumb dictates the total fabric area and the cost of
the control unit.
Depending on gas temperatures involved, polyester, aramide, or
fiberglass fabrics may be used for the secondary emissions. If certain
operations should happen to be near the filter unit, it is conceivable that
hot particles may be cast onto the fabric. Since the smaller particles
cool more rapidly, it is necessary to provide a "spark box" to deflect the
larger ones.
Dust-handling facilities must be provided. Ideally the collected
solids are recycled to the process via the sinter plant. If however, the
charge is in part galvanized or terne scrap, the charging emissions may
contribute unacceptable levels of zinc or lead to the filter catch. Since
these ingredients are detrimental to blast furnace refractory linings, such
solids (in this country) are commonly landfilled.32
Fabric filters areiin use for several steel process gas cleaning
applications. The facility at Kaiser Steel for secondary emission control
treats waste gases from charging, tapping, puffing (during oxygen blow),
furnace deslagging, hot metal transfer, and hot metal skimming. Fabric
filters are used to collect hot metal transfer emissions at the Bethlehem
Steel plant in Bethlehem, Pennsylvania, Inland Steel's No. 4 BOPF shop, and
Wheeling-Pittsburgh's BOPF shop near Steubenville, Ohio. Fabric filters
are also applied to electric arc furnace EAF emissions at the three Babcock
4-43
-------
and Wilcox shops in Beaver Falls, Pennsylvania, and the Marathon Le Tourneau
Company steel mill in Longview, Texas. In addition to the several U.S.
installations, there are many secondary emission control systems with
fabric filter collectors in use in BOPF shops outside the U.S., particularly
Japan, but also several European plants.
Performance test data are available from fabric filter controlled
systems applied to both BOPF secondary sources and electric arc furnaces.
Because the particulate characteristics are similar, data on the performance
of electric arc furnace enclosures are applicable to BOPF secondary emission
control baghouses. Figure 4-11 presents the performance data graphically.
As is evident all of the outlet concentrations are below 0.011 grams/SCMD
(0.005 grains/SCFD). Brief descriptions of the installations are provided
in the paragraphs below.
Babcock and Wilcox's Wallace Run Shop No. 1 has two 22.7 tonne EAFs
served by a building evacuation system. One pressure type baghouse with
ten compartments serves this shop. The bag size is 29.2 cm diameter by
9.14 m long (11.5 in. by 30 ft) installed on 38.1 cm (15 in.) centers,
three deep from the aisle. The fabric in use is Dacron.w8 A design net
air to cloth ratio of 0.91:1 m/min (3.0:1 ft/min) with two compartments out
of service was selected. The fan supplied with the system has a design air
flow of 6,520 m3/min (230,000 ACFM). Bag cleaning is provided by a reverse
air system. Performance tests were made in accordance with EPA Method 5.23
The Wallace Run Shop No. 2 has two EAF furnaces of 45.5 and 68.2 tonne
capacity. A building evacuation system similar to the No. 1 shop's is
used. Bag fabric and sizes are the same as in the No. 1 shop. Two fans of
6,520 m3/min capacity are provided for the No. 2 shop.18 Test data were
collected by EPA Method 5.33
The Koppel shop has a 45.5, 68.2, and three 90.9 tonne EAFs. A
building evacuation system with three baghouses is provided for this plant.
The baghouse sizes, bag sizes, and bag fabric are the same as for Wallace
Run No. 1 shop. The two smaller furnaces are served by two 6,520 m3/min
fans. Two of the large furnaces are served by three 6,520 m3/min fans.
The other large furnace plus a future large furnace also have three fan
service of the same capacity.18 EPA Method 5 was the test method used for
the reported performance data.33
4-44
-------
en
0.020
0.018
0.016
0.014
0.012
" 0.010
"O
£ 0.008
1
o 0.006
+3
n>
c 0.004
0)
0
e
S 0.002.
0.000
_ _
_ _
-
™ -
O
•• _
° 0 °
O E ^
0 Q | 0
.©©208©
0 g 0
A B C 1 D E 1
Plant Code
A-B&U Wallace Run No. 1
Bldg. Evac. EAF
B-B&VJ Wallace Run No. 2
Bldg. Evac. EAF
C-B&W Koppel
Bldg. Evac.
D-Marathon LeTourneau
Canopy & Side Draft
Hoods - EAF
E- In! and Steel No. 4
BOPF - Local Hood -
HMT
Plant Identification
Figure 4-11. Fabric Filter Outlet Concentration for BOPF and EAF Sources.
-------
The Marathon Le Tourneau plant produces high strength, low alloy,
specialty steel in two 27.3 tonne capacity EAFs.34 The gas cleaning system
includes combined side draft and canopy hoods. Charging and tapping
emissions are captured by the canopy hoods and the side draft hoods are
used when the furnace roofs are in place. Particulate removal is provided
by a ten- compartment baghouse. The total cloth area is 4,903 m2 for a
design gas flow rate of 4,820 mVmin at 66°C (150° F). The net air to
cloth ratio is 1.09:1 m/min (3.58:1 ft/min) with one compartment out of
service. The bags in use are Dacron fabric, 12.7 cm diameter by 4.27 m
long (5 in. by 14 ft). Bags are cleaned on a timed cycle by shaking.
Performance tests were made in accordance with EPA Method 5.
The Inland Steel tests data were obtained from a baghouse applied to
the hot metal transfer station emissions in the No. 4 BOPF shop. The
performance tests were made in accordance with EPA Method 5. Details of
the baghouse design are not available at present.
Details of the Kaiser Steel secondary emission control baghouse are
provided in Section 4.2.1.1.
4.4.2 Wet Scrubbers
This class of particulate-control devices has been amply
described.29 35 Scrubbers are most frequently used for primary emissions
control. A few scrubbers are currently used for secondary emissions
control.3 15 16
The operating principle of the venturi scrubber is, briefly, as
follows. The dusty gas is forced into a constriction, where it attains a
velocity in the range 50 to 150 m/s (150 to 500 ft/s). At about this point
the dusty gas encounters a sheet or spray of liquid (ordinarily recirculated
water) having a relatively low velocity. The interaction creates many
small droplets that rapidly attain the velocity of the gas. While the
droplets are accelerating the air must pass around each droplet and the
heavier particles tend to impact on the droplets in the process . More
water and a higher (initial) relative velocity permit the collection of
finer particles.
The pressure drop across the device is 80 to 120 cm of water (30 to 50
in.) or more and the fan work is accordingly high. In fact, the energy
consumption of the venturi scrubber is the highest of the three high
performance control units described in this section.
4-46
-------
Downstream of the venturi proper, a cyclone separates the dirty water
droplets from the gas. The resulting slurry of particles in water is
conveyed to a settling pond or a thickener, from which a relatively clean
overflow is recirculated. Makeup water is required because the dusty gas
is hot and must be cooled by evaporation of a direct spray of water. The
underflow from a thickener may be filtered and the wet cake recycled under
certain circumstances, as described in Section 4.4.1. Performance data are
available from one venturi scrubber serving the secondary emission control
system at Inland Steel's No. 2 BOPF shop.16 Information on the plant and
system design is given in Section 4.2.3.1. Table 4-13 presents the results
of measurements made on this system. Scrubber outlet concentrations were
measured during three variations of furnace production cycles. Tests on
normal and sulfur heats began with hot metal charging and ended at the end
of tapping. During the preheat production cycles, testing began at the
preheat and ended at the end of tapping. The highest average outlet
concentration for any of the production cycle types was 0.016 grams/DSCM
(0.007 grains/DSCF). The highest concentration measured on any run was
0.0321 grams/DSCM (0.014 grains/DSCF).
4.4.3 The Electrostatic Precipitator
This control device has also been amply described.30 36 When a static
potential of several thousand volts is maintained between a metal plate and
a wire parallel to it, gas moving through the space between will be ionized
(corona discharge). The resulting ions and electrons become attached to
dust particles in the gas, usually imparting a net charge. The particles
thus charged experience a coulombic attraction toward the plate or grounded
electrode. The larger particles will reach the plate and be removed from
the gas before it leaves the apparatus. A higher potential (voltage)
(within limits) or more residence time will cause the collection of finer
particles.
The dust cake that builds up on the plates may fall off by its own
weight, or it may be dislodged by mechanical impact on the plate or by
washing. Dry dust can be handled as in the fabric filter case, and the
slurry from a wet ESP is comparable to that from a wet scrubber.
Precipitators for large-scale, continuous applications are normally
compartmentalized. This requires independent power supplies but permits
some maintenance without shutdown.
4-47
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TABLE 4-13. INLAND STEEL, EAST CHICAGO, INDIANA SECONDARY EMISSION
CONTROL SYSTEM PERFORMANCE TEST RESULTS16
Normal heat
Front half concentration - grams/DSCM
Run 1 Run 2 Run 3
0.0092
0.0160
0.0321
Average
0.014
Sulfur heat
0.0069
0.0206
0.0206
0.0160
Preheat heat
0.0138
0.0115
0.0206
0.0153
4-48
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A limiting voltage has been referred to above. When the voltage is
raised to a certain level that depends on the gas, its temperature and
humidity, the geometry, and the character and thickness of the cake, an
unstable arc replaces the stable corona discharge. The arc is of no use to
the process and may damage the power supplies if continued. Therefore,
progressively better performance is achieved as the potential is raised,
until an arc is struck. In modern ESPs the power supply automatically
reduces voltage when arc occurs, brought back up until another arc occurs,
and so on. A fortunate consequence of this equipment feature is the ability
of the system to track the continually changing composition and temperature
of the primary or secondary BOPF emissions.
Because the ionizing behavior of the gas and the character of the cake
depend on gas temperature and composition, it is sometimes desirable to
"condition" the gas. This may be as simple as adding moisture, but in
other industries it has been found feasible to inject such components as
ammonia, ozone, or sulfur trioxide. For primary BOPF applications, moisture
(as water or steam) is essential to good performance.
The distinctive feature of the ESP in the steel industry is its low
power consumption—the lowest of the three devices considered here.
Secondary emissions collection by ESPs in the U.S. is the result of putting
the secondary gas stream through a primary system or conversion of ESPs
once used for primary emissions to secondary system applications. No new
ESPs have been constructed specifically for BOPF secondary emission control.
Previous mention was made in this chapter of steel plants outside the U.S.
having constructed roof-mounted ESPs specifically for secondary emission
control. These BOPF roof installations are primarily supplements to local
hoods connected to fabric filters. In the case of the Kawasaki Steel,
Chiba Works Q-BOPF, the roof-mounted ESP is an effective addition to control
the difficult fugitive emissions generated by bottom blowing when the
furnace is turned down.14 The design inlet concentration for this plant is
0.4 grams/SCM and the corresponding outlet is 0.03 grams/SCM.837 Actual
measurements have shown an inlet maximum of 1.09 grams/SCM and a maximum
outlet of 0.038 grams/SCM. In two other installations outlet concentrations
as low as 0.02 grams/SCM have been measured. Additional collector surface
area could provide lower outlet concentrations, but increased collector
size and weight would result.
4-49
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4.5 REFERENCES
1. Coy, D. W. et al. Pollution Effects of Abnormal Operations in Iron and
Steel Making—Volume VI. Basic Oxygen Process, Manual of Practice.
U.S. Environmental Protection Agency. Research Triangle Park, NC.
EPA-600/2-78-118f. June 1978
2. Drabkin M. and R. He!fand. A Review of Standards of Performance for New
Stationary Sources—Iron and Steel Plants/Basic Oxygen Furnaces.
U.S. Environmental Protection Agency. Research Triangle Park, NC.
EPA-450/3-78-116. November 1978.
3. Williams, A. E. and K. W. Hazard. The Engineering and Installation of
Two 225-Ton Q-BOP Vessels in an Open-Hearth Shop. Iron Steel Engr. 55
(11):33. November 1978.
4. Nicola, A. G. Fugitive Emission Control in the Steel Industry." Iron
Steel Engr. 53(7):25. July 1976.
5. Trip Report. Nippon Steel Corporation, Oita Works. Research Triangle
Institute. September 19, 1979.
6. Trip Report. Nippon Steel Corporation, Yawata Works. Research Triangle
Institute. September 20, 1979.
7. Trip Report. Kaiser Steel. Fontana, California. Research Triangle
Institute. December 2, 1979.
8. Letter and attachments from Martzloff, J. A. Kaiser Steel Corporation,
to Goldman, L. J., Research Triangle Institute, December 13, 1979.
Response to BOPF Questionnaire.
9. Clayton Environmental Consultants. Steel Processing Fugitive Emissions -
Emission Test Report Kaiser Steel Corporation, Fontana, California. U.S.
Environmental Protection Agency. Research Triangle Park, NC. EMB Report
80-BOF-3. August, 1980.
10. GCA Corporation. Assessment of Air Emissions From Steel Operations,
Republic Steel Corporation, Chicago District Q-BOP Shop Emission
Evaluation. U.S. Environmental Protection Agency, Washington, D.C.
Contract No. 68-01-4143, Task No. 58 Report. September, 1979.
11. Clayton Environmental Consultants. Steel Processing Fugitive Emissions -
Emission Test Report Republic Steel Company, South Chicago, Illinois.
U.S. Environmental Protection Agency, Research Triangle Park, N.C.
EMB Report 80-BOF-7. September, 1980.
12.
13.
Trip Report. Republic Steel Corporation, Cleveland, Ohio.
Triangle Institute, December 11, 1979.
Research
Steiner, J., and L. Kertcher. Fugitive Particulate Emission Factors for
BOP Operations. In: First Symposium on Iron and Steel Pollution Abatement
Technology, Ayer, F. A. (ed.). U.S. Environmental Protection Agency.
Research Triangle Park, N.C. EPA-600/9-80-012. February 1980.
P-252-271. 4_50
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14. Clayton Environmental Consultants. Steel Processing Fugitive Emissions -
Emission Test Report, Republic Steel Company, Cleveland, Ohio. U.S.
Environmental Protection Agency, Research Triangle Park, N.C. EMB Report
80-BOF-8. ?, 1980.
15. Coy, D. W. and R. Jablin. Review of Foreign Air Pollution Control
Technology for BOF Fugitive Emissions. In: First Symposium
on Iron and Steel Pollution Abatement Technology, Ayer, F. A. (ed.).
U.S. Environmental Protection Agency. Research Triangle Park, NC
EPA-600/9-80-012. February 1980. p. 233-251.
16. Letter with attachments from Lang, D. C., Inland Steel Company to
Goldman, L. J., Research Triangle Institute. May 12, 1980. Response to
BOPF Questionnaire.
17. York Research Corporation. Inland Steevl Plant No. 2, Indiana Harbor
Works, East Chicago, Indiana, Visible Emissions Observations Measurements
Program. U.S. Environmental Protection Agency. Research Triangle Park,
N.C. EMB Report 80-BOF-?. ?, 1980.
18. Trip Report. Babcock and Wilcox, Beaver Falls, Pennsylvania. Research
Triangle Institute. June 29, 1977.
19. Trip Report. Crucible, Inc., Midland, Pennsylvania. Research Triangle
Institute. August 4, 1977.
20. Caine, K. E. Jr. Development of Technology for Controlling BOP Charging
Emissions. U.S. Environmental Protection Agency, Research Triangle Park,
N.C. EPA-600/2-77-218. October, 1977.
21. Gaw, R. C. Containment of Oust and Fumes from a Metallurgical Vessel.
U.S. 3,854,709. December 17, 1974.
22. GCA Corporation. Assessment of Air Emissions From Steel Plant Operations,
Republic Steel Corporation, Gadsden, Alabama. U.S. Environmental
Protection Agency. Washington,' D.C. Contract No. 68-01-4143, Task Order
58 Report. March, 1980.
23. Trip Report. Bethlehem Steel, Bethlehem, Pennsylvania. Research
Triangle Institute. May 21, 1980.
24. Letter and attachments from Ricketts, A. T. Bethlehem Steel Corporation,
to McGrogan, J. E. Pennsylvania Department of Environmental Resources,
July 14, 1977. Test report on Bethlehem Pennsylvania BOPF shop.
25. Clayton Environmental Consultants. Steel Processing Fugitive Emissions -
Emission Test Report, Bethlehem Steel Corporation, Bethlehem, Pennsylvania.
U.S. Environmental Protection Agency, Research Triangle Park, N.C.
EMB Report 80-BOF-9. Report not yet issued.
26. Trip Report. Italsider Steel Company, Taranto Works. Research Triangle
Institute. March 26, 1979.
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27. Trip Report. Kawasaki Steel Corporation, Chiba Works. Research Triangle
Institute. September 25, 1979.
28. Watanabe, T. Ventilation Method and Apparatus with Dust Collection by
Electric Static Precipitator. U.S. 3,844,205. October 29, 1974.
29. Perry, R. H. et al. Chemical Engineers' Handbook. 4th Edition,
New York. McGraw-Hill. 1963. p. 5-62.
30. Air Pollution Control Equipment for Particulate Matter. Danielson, J.A.
(ed.). In: Air Pollution Engineering Manual, AP-40, 2nd Edition.
Washington, U.S. Government Printing Office. May, 1973.
31. Billings, C. E. and J. Wilder. Fabric Filter Systems Study. Two
Volumes. U.S. Environmental Protection Agency, Research Triangle Park,
NC. NAPCA APTD-0690-0691. December, 1970. Also available from
National Technical Information Service PB 300 648,-649.
32. Baldwin, V. H. et al. Environmental and Resource Conservation
Considerations of Steel Industry Solid Waste. U.S. Environmental
Protection Agency. Research Triangle Park, N.C. EPA-600/2-79-074.
April 1979.
33. Background Information For Standards of Performance: Electric Arc Furnaces
in the Steel Industry, Volume 2: Test Data Summary. U.S. Environmental
Protection Agency, Research Triangle Park, N.C. EPA-450/2-74-017b.
October, 1974.
34. Cass, R. W., and J. E. Langley. Fractional Efficiency of an Electric
Arc Furnace Baghouse. U.S. Environmental Protection Agency, Research
Triangle Park, N.C. EPA-600/7-77-023. March, 1977.
35. Calvert, S. et al. Wet Scrubber System Study. Two Volumes. U.S.
Environmental Protection Agency, Research Triangle Park, NC.
EPA-R2-72-118a, -118b. July and August 1972. Also available from
National Technical Information Service PB 213 016,-017.
36. Oglesby, S. and Nichols. A Manual of Electrostatic Precipitator
Technology. Two Volumes. U.S. Environmental Protection Agency, Research
Triangle Park, NC. NAPCA APTD-0610, -0611. August 1970. Also available
from National Technical Information Service PB 196 380,-381).
37. Ito, S. et al. Roof-Mounted Electrostatic Precipitator. In: Symposium
on the Transfer and Utilization of Particulate Control Technology,
Volume 1. U.S. Environmental Protection Agency. Washington, D.C.
EPA-600/7-79-044a. February, 1979. p. 485-495.
4-52
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.5. MODIFICATION AND RECONSTRUCTION
In accordance with Section 111 of the Clean Air Act, as amended in
1977, standards of performance shall be established for new sources within
a stationary source category that "may contribute significantly to air
pollution " Affected facilities are those for which standards of
performance have been promulgated and whose construction or modification
began after the proposal of the standards.
Under the provisions of 40 CFR 60.14 and 60.15, an "existing facility"
may become subject to standards of performance if deemed modified or
reconstructed. An "existing facility" as defined in 40 CFR 60.2(aa) is a
facility for which a standard of performance has been promulgated but for
which construction or modification began before the date of proposal of
that standard. The following discussion examines the applicability of
these provisions to basic oxygen process furnace facilities and describes
conditions under which existing facilities could become subject to standards
of performance.
It is important to note that a stationary source may contain both
affected and existing facilities and that reclassifying a facility from
existing to affected status by new construction, modification, or
reconstruction does not necessarily subject any other facility within that
source to standards of performance.
5,1 SUMMARY OF 40 CFR 60 PROVISIONS FOR MODIFICATIONS AND RECONSTRUCTIONS
5.1.1 Modification
Section 40 CFR 60.14 defines modification as follows:
"Except as provided under paragraph (e) and (f) of this section,
any physical or operational changes to an existing facility which
result in an increase in emission rate to the atmosphere of any
pollutant to which a standard applies shall be a modification.
Upon modification, an existing facility shall become an affected
5-1
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facility for each pollutant to which a standard applies and for
which there is an increase in the emission rate."
Paragraph (e) specifies certain physical or operational changes that
are not considered as modifications, irrespective of any changes in the
emission rate. These changes include:
1. Routine maintenance, repair, and replacement;
2. An increase in production rate accomplished without a capital
expenditure [as defined in Section 60.2(bb)];
3. An increase in hours of operation;
4. Use of alternate fuels or raw materials if the existing facility
were designed to accommodate the alternate fuel or raw material
prior to the standard (conversion to coal required for energy
considerations, as specified in Section 111 (a)(8) of the Clean
Air Act is also exempted.);
5. Addition or use of any system or device whose primary function is
the reduction of air pollutants, except when an emission control
system is removed or replaced by a system considered to be less
efficient; and
6. Relocation or change in ownership.
Paragraph (f) provides for superseding any conflicting provisions.
Paragraph (b) of CFR 60.14 clarifies what constitutes an increase in
emissions and the methods for determining the increase. These methods
include the use of emission factors, material balances, continuous
monitoring systems, and manual emission tests. Paragraph (c) of CFR 60.14
affirms that the addition of an affected facility to a stationary source
does not make any other facility within the source subject to standards of
performance.
5.1.2 Reconstruction
Section 40 CFR 60.15 defines reconstruction as follows:
An existing facility, upon reconstruction, becomes an affected
facility, irrespective of any change in emission rate.
'Reconstruction' means the replacement of components of an
existing facility to such an extent that: (1) the fixed capital
cost of the new components exceeds 50 percent of the fixed capital
cost that would be required to construct a comparable entirely
5-2
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new facility, and (2) it is technologically and economically
feasible to meet the applicable standards set forth in this part.
The purpose of this provision is to ensure that an existing facility
is not perpetuated by replacing all but minor components such as support
structures, frames, and housing rather than totally replacing the facility
in order to avoid becoming subject to applicable standards of performance.
5.2 APPLICABILITY TO BOPF FACILITIES
5.2.1 Potential Modification
Changes in a BOPF facility that might be covered by Section 40 CFR
60.14 include:
1. Increasing furnace capacity,
2. Conversion of an existing vessel to the KMS top and bottom blowing
system, and
3. Addition of scrap preheat capability.
5.2.1.1 Increasing furnace capacity. An increase in furnace capacity
can be achieved by relining the vessel with thinner refractory material
which results in a thinner furnace wall but increased furnace volume. This
would ordinarily be done during the normal reline phase of the vessel
campaign. Although production capacity would be increased, this increase
would be incidental to normal routine maintenance procedures and would,
therefore, not be considered a modification of the facility. As a
consequence of furnace enlargement, associated facilities, such as hot metal
transfer and skimming, would have higher production rates and increased
emissions. These facilities, however, would not be regarded as having been
modified unless some physical changes had been made to accommodate the
production increase.
5.2.1.2 KMS system conversion. At the present time two existing BOPF
shops owned by the National Steel Corporation are being converted to the
KMS system. With this system installed, it will be possible to inject coke
into the bottom of the furnace. The coke, serving as fuel, would increase
the melting capacity of the furnace thereby increasing the proportion of
scrap that would be added to each charge. Scrap preheating is also possible
with this system. Although no test data are available, National Steel
claims that, compared to the original top blown system, lower amounts of
5-3
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fumes and dust will be emitted during the oxygen blow.1 The similarity of
this system to the Q-BOPF system suggests, however, that greater quantities
of fumes and dust will be emitted during charging, turndown, and tapping.
5.2.1.3 Addition of scrap preheat capability. With preheating, a
larger proportion of scrap can be used in each charge. Preheating can be
accomplished by injecting oxygen and fuel through the lance in top blown
vessels or through the tuyeres in Q-BOPFs and KMS system conversions. The
fuel can be gas or oil. Preheating would increase the total emissions from
the BOPF cycle through the generation of combustion products. However, it
is possible that this increase may be slightly offset by a reduction in hot
metal charging emissions since the molten iron would no longer be poured on
top of cold scrap.
5.2.1.4 Applicability of emission control techniques. Emission
control techniques discussed in Chapter 4 would be applicable for
controlling particulate emissions resulting from the BOPF facility changes
discussed above. Rulings on whether alterations within BOPF shops
constitute a modification can be obtained by contacting a U.S. Environmental
Protection Agency Regional Office of Enforcement.
5.2.2 Reconstruction
When an owner or operator replaces several components of an existing
facility, that facility may or may not become subject to applicable
standards of performance under the provisions of Section 60.15. Replacement
of major equipment components may be considered as reconstruction if the
fixed capital costs for the replaced equipment exceed 50 percent of the
costs of constructing an entirely new facility. However, it does not
appear likely that existing BOPF shops, with normal repair and maintenance
practices, will become affected facilities by virtue of the reconstruction
provision, as discussed in Section 5.1.2.
Repair and replacement of vessel linings are generally considered
routine maintenance for a basic oxygen process furnace. Consequently these
costs are not to be included in making reconstruction determinations.
Ruling on whether alterations within BOPF shops constitute a reconstruction
can be obtained by contacting a U.S. Environmental Protection Agency Regional
Office of Enforcement.
5-4
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5.3 REFERENCES
1. Anonymous, National Blueprints Big BOP Shop Conversion. 33 Metal
Producing. November 1979.. p. 63.
5-5
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6. MODEL PLANTS AND REGULATORY ALTERNATIVES
The impact of various emission control regulations on BOPFs is
determined through an analysis of model plants. Model plants are parametric
descriptions of both the types of plants that are presently in operation
and those which, in EPA's judgement, may be constructed, modified, or
reconstructed in the future.
6.1 MODEL PLANTS
6.1.1 Model Plant Selection
Eight model plants have been developed to represent the basic oxygen
process furnace (BOPF) source category. Descriptions of the plants are
presented in Table 6-1 along with a model for a hot metal transfer and slag
skimming facility.
Two sizes of furnace vessels are represented in the models, with
design capacities of 150 tons and 300 tons. Actual heat sizes may vary
slightly depending on production requirements and hot metal availability.
The 150-ton models are representative of some older shops and those shops
are involved in the production of specialty steels. The 300 ton vessel
models characteristic of the major, high volume, steel production facilities
that exist today in the United States.
Several operational modes are possible in multiple vessel shops. In a
two vessel shop, one vessel may be used while the second one remains idle,
or alternatively, both vessels may be in service at the same time with some
overlap possible in their cycles (for example, one vessel may be charged or
tapped while the other vessel is in the blowing phase). In a three vessel
shop one or two vessels may be in operation while the third is idle.
The model plants are further divided on the basis of the type of
primary fume collection hood present. This distinction is made because
some shops with open primary hoods can utilize these systems to enhance
secondary emission control. Most of the older plants have open primary
6-1
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TABLE 6-1. MODEL PLANTS
Steel production
Case Model tons/year
A Two new 300 ton vessels, closed hood, top blown, equipped 3,200,000
with furnace enclosure and baghouse.
B One new 300 ton vessel added to two existing 300 ton 5,900,000
vessels, closed hoods, top blown, equipped with furnace
enclosure and baghouse.
C Two new 300 ton vessels, closed hood, bottom blown, 3,200,000
equipped with furnace enclosure and baghoue.
D One new 300 ton vessel added to two existing 300 ton 5,900,000
vessels, open hood, equipped with baghouse.
E Two existing 300 ton vessels converted to KMS process, 3,200,000
closed hood, top and bottom blown, equipped with furnace
enclosure and baghouse.
F Two new 150 ton vessels, closed hood, top blown, equipped 1,600,000
with furnace enclosure and baghouse.
G One new 150 ton vessel added to two existing 150 ton 2,900,000
vessels, closed hood, top blown, equipped with furnace
enclosure and baghouse.
H Two new 300 ton vessels, closed hood, bottom blown, 3,200,000
equipped with furnace enclosure and baghouse. Conversion
of an open hearth shop to basic oxygen process.
I Hot metal transfer and slag skimming station. —-
6-2
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hoods in which complete combustion of the process off-gas takes place
(complete combustion system). The trend in new shops is towards the
installation of closed primary hoods that limit combustion of the off-gas
to about 10 percent of the total volume of combustible gas generated
(suppressed combustion system). The high concentration of combustible gas
remaining in the exhaust makes it essential to use a scrubber for gas
cleaning. After cleaning, the combustible gases are flared at the stack.
The exhaust rate in a closed hood system is considerably less than in an
open hood system (generally about 25 percent of the volume of an open hood
system) because excess air for combustion is excluded.
Model A (Table 6-1) is representative of a new shop with two 300 ton
top blown vessels. The secondary emission control systems consist of full
furnace enclosures, equipped with charging and tapping hoods, ducted to a
common baghouse. Model C is a similar installation with bottom blown
furnaces (Q-BOPFs). Model H is also a Q-BOPF shop but unlike Model C,
which is a greenfield facility, this model represents the conversion of an
existing open hearth shop to basic oxygen process steel making. Q-BOPFs
would be chosen for this conversion since they do not require much overhead
clearance and would therefore fit into the existing building. Models B and
D are representative of the addition of a third 300 ton vessel to an
existing two vessel shop. The addition of a third vessel is most likely to
occur when demand for steel is great. Increased BOPF production capacity
might require expansion of other steel making facilities such as blast
furnaces and coke ovens.
Model E is representative of the conversion of two existing 300 ton
top blown vessels to the Klochner Maxhutte Scrap (KMS) system, in which the
vessels are blown simultaneously from both the top and bottom. This model
is included because two BOPF shops in the United States are currently being
converted to the KMS system. If the conversion is successful other shops
are likely to follow suit.1 Although the current KMS conversion is being
performed on vessels with open hoods, there seems to be no technical reason
why the system could not be installed on vessels equipped with closed
hoods. The secondary emissions generated by KMS system vessels are likely
to be very similar to those generated by bottom blown vessels (Q-BOPs).
6-3
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Model F represents a greenfield shop with two 150 ton vessels. The
secondary emission pollution control system consists of full furnace
enclosures, with charging and tapping hoods, ducted to a common baghouse.
Model G represents the addition of a third vessel to an existing shop with
two 150 ton vessels.
The hot metal transfer (reladling) and slag skimming station
represented by Model I consists of a single hood over the reladling pit.
Both reladling and skimming would take place under the same hood. A single
station would be sufficient for most plants although a second one might be
installed as a backup.
6.1.2 Fugitive Emission Sources
Within the BOPF shop, the processes that generate fugitive emissions
are hot metal transfer, skimming, scrap charging, hot metal charging,
puffing during the oxygen blow, vessel turndown for sampling, tapping the
heat, deslagging, teeming, slag handling, ladle maintenance (lancing,
gunning, preheating, etc.), and flux handling.
Emission factors and estimates of the uncontrolled and controlled
emissions rates for each of the model plants are presented in Table 6-2.
Because emission factors have not been developed for eight of the twelve
fugitive emission sources listed above,2 the emission estimates are based
on the contributions of only four sources: hot metal transfer, hot metal
charging, tapping, and teeming.
The KMS system is not yet in operation and so it is likely that no
emission factors have been developed for any phase of the operation of this
type of vessel. However, as a first approximation, since the KMS vessels
are bottom blown, the emission factors developed for Q-BOPFs have been used
in developing the emission estimates for the KMS conversion model plant
(Model plant E, Table 6-2.)
Three separate emission estimate tables, based on enclosure capture
efficiencies of 60, 80, and 100 percent, have been developed for the model
plants with bottom blown vessels (Models C, E, and H). This was done
because tests performed in the best controlled Q-BOPF shop in the United
States revealed that the furnace enclosure fume capture efficiency was less
than 100 percent but was estimated to be better than 60 percent. There are
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TABLE 6-2. EMISSION TABLE FOR BOPF MODEL PLANTS
Model plant
A
B
C
(100% capture)
( 80% capture)
( 60% capture)
D
E
(100% capture)
( 80% capture)
( 60% capture)
F
G
H
(100% capture)
( 80% capture)
( 60% capture)
Uncontrolled
1,587
2,947
3,047
3,047
3,047
3,259
3,047
3,047
3,047
793
1,391
3,047
3,047
3,047
Total emissions, tons
Furnace enclosure
428
2,333
476
981
1,487
2,646b
762
1,267
1,773
246
1,097
476
981
1 ,487
per year
Building
0.003
467
a
376
376
376
a
376
376
376
287
a
376
376
376
evacuation0
0.01
1,398
a
971
971
971
a
971
971
971
793
a
971
971
971
.Building evacuation not a viable option.
Hooding rather than furnace enclosure.
At 0.003 gr/scf and 0.01 gr/scf outlet loadings from baghouse.
6-5
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no reliable estimates available for the actual proportion of secondary
emissions captured at this facility.
Based on the emission estimates in Table 6-2, furnace enclosures with
charging and tapping hoods would provide the best emission control for
virtually all the BOPF model plants. The only exceptions to this are the
bottom blown furnace cases for which the estimated enclosure capture
efficiencies are assumed to be 80 percent and 60 percent. In the 80 percent
case building evacuation is marginally better than the enclosure whereas in
the 60 percent case the building evacuation provides a substantially greater
reduction in emissions. The cost effectiveness of all these systems is
discussed in Chapter 8.
6.2 REGULATORY ALTERNATIVES
6.2.1 Regulatory Alternative Overview
Regulatory alternatives are defined as the various courses of action
that EPA considers for regulating emissions from BOPF shops. Initially, a
survey is conducted to identify the emission control techniques applicable
to BOPFs and to determine their effectiveness. The regulatory alternatives
are based on the data gathered in this survey. Each regulatory alternative
is evaluated with respect to environmental, energy, and economic impacts.
Based on these evaluations, one regulatory alternative is identified as
representing the best approach to limiting BOPF shop fugitive emissions.
The options for setting the standards for secondary emissions range
from imposing no additional emission limits (no standard set) to the most
costly option, which prohibits all visible roof monitor emissions. Some
options also set performance standards for gas cleaning devices.
In some shops that contain unregulated sources, a roof-monitor standard
would have to allow for emissions seen at the monitor that may not be
easily attributable to a given source within the shop. The approach for
these cases would be to allow unregulated sources to be shut down during
compliance testing. An alternate approach would be to set an equipment
standard which could be applied to sources subject to regulation.
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6.2.2 Regulatory Alternative I
This regulatory alternative would not prescribe any controls for
secondary emission sources in new or modified BOPF shops.
6.-2.3 Regulatory Alternative II
6.2.3.1 Greenfield facilities. The affected sources in greenfield
BOPF shops are hot metal transfer, skimming, and furnace operations.
Sources that would remain uncontrolled are teeming, slag handling, ladle
maintenance, and flux handling. The operation of these sources should not
cause a new shop to be out of compliance since the proposed regulations are
based upon the performance of shops in which these sources were both
uncontrolled and operating.
Emissions generated during hot metal transfer and skimming could be
controlled with local hooding ducted to a secondary emissions collection
system gas cleaning device. Effective facilities at which tests were
conducted (See Chapter 4, Section 4.3) were exhausted at a rate of
approximately 200,000 acfm. Gas cleaning was accomplished with a baghouse.
Charging and tapping emissions from closed hood furnaces can be
controlled effectively with full furnace enclosures equipped with charging
and tapping hoods. Suggested evacuation rates for 300 ton vessels are
600,000 ACFM for top blown furnaces and 750,000 acfm for bottom blown
furnaces. Effective gas cleaning can be achieved with a baghouse although
scrubbers or ESPs can also be used. Full furnace enclosures probably would
not be suitable for open hood systems in which a limitation on the amount
of air available for primary fume combustion might create an explosion
hazard. For these systems, partial enclosures with charging and tapping
hoods would provide adequate control.
Emissions from top blown, 150 ton furnaces would be controlled as
described above for 300 ton furnaces with the exception that the secondary
system evacuation rate could be reduced to 400,000 acfm. Canopy hood
systems or partial building evacuation systems may be effective alternatives
to furnace enclosures. At the present time, however, the test data are
insufficient to support the efficacy of either of these systems.
The effectiveness of BOPF secondary emissions control systems could be
evaluated and regulated by means of a roof-monitor opacity standard. This
6-7
-------
would be done when only one vessel was operating because the data supporting
potential standards were obtained in shops operating single vessels. An
alternative approach would be to impose an equipment standard that would
require the installation of local hooding at the hot metal transfer and „
skimming station as well as furnace enclosures equipped with charging and
tapping hoods. Evacuation rates would also be specified. In either case,
emissions limits would be specified for the gas cleaning devices.
6.2.3.2 Third vessel addition to an existing two vessel shop. In the
event that a roof monitor opacity regulation is adopted, the addition of a
third vessel to an existing shop would pose a special problem. This problem
arises because the new vessel is the only affected facility in the shop and
other nonregulated sources might be emitting fumes during compliance testing
or during enforcement procedures. One solution would be to shut down the
affected sources during testing. An alternate approach would be to adopt
an equipment standard for the new furnace. The required emission control
equipment would be a furnace enclosure with a charging and tapping hood
evacuated at a specified rate to a gas cleaning device. A canopy hood
system restricted to the region of the new vessel might be a good
alternative system although the effectiveness of such a system has not been
documented. Partial or complete building evacuation systems would not be
appropriate in this application since such systems would, in effect, impose
emission control on unregulated sources.
An equipment standard calling for local hooding evacuated to a gas
cleaning device would be the appropriate regulatory approach if a new hot
metal transfer and skimming facility were being added to an existing shop.
6.2.3.3 Conversion of existing vessels to the KMS system. A
conversion of existing vessels to the KMS system would subject the vessels
to compliance under the proposed regulations. As in the cases discussed
above, a roof monitor opacity standard would be applicable only when
nonaffected sources within the shop were shut down. Another regulatory
approach would be to adopt an equipment standard calling for furnace
enclosures with charging and tapping hoods evacuated at a prescribed rate
to a gas cleaning device.
6-8
-------
6.2.4 Regulatory Alternative III
The third regulatory alternative is total building evacuation at the
rate of one complete air change every 2.5 minutes. This option would be
appropriate only for greenfield shops with no preexisting unregulated
sources.
6.2.5 Gas Cleaning Systems
Baghouses will probably be the most common gas cleaning device used on
BOPF secondary emission systems. Scrubbers and electrostatic precipitators
might be used in some shops but, at the present time, only limited test
data are available to support the efficacy of these devices. Regardless of
the type of device selected, it would be expected to meet both mass emission
and outlet opacity limits.
6.3 REFERENCES
1. Anonymous, National Blueprints Big BOP Shop Conversion. 33 Metal
Producing. November 1979. p. 63.
2. Cuscino, T. Particulate Emission Factors Applicable to the Iron and
Steel Industry. Midwest Research Institute, Kansas City, Missouri.
EPA-450/4-79-028. September 1979. pp. 27-31.
6-9
-------
7. ENVIRONMENTAL IMPACT
Chapter 7 identifies the productive and adverse environmental changes
caused by addition of BOPF secondary emission controls.
The following impacts are discussed:
1. The impact of reducing particulate and other air emissions.
2. The impact of emission control on water pollution.
3. The impact of emission control on solid wastes.
4. The energy impact of emission control.
5. Other environmental impacts, such as noise.
6. Other environmental concerns, such as resource committments and
trade-offs.
7.1 AIR POLLUTION IMPACT
As stated in Chapter 6, Table 6-2, the uncontrolled secondary emission
of particulate matter from BOPF hot metal transfer, charging, tapping, and
teeming ranges from 460 to 915 g/Mg (0.92 to 1.83 Ibs/ton) of steel
produced, or up to about 75,000 Mg (83,000 tons) per year nationwide at
full production. These emissions are based on BOPF capacity estimates
given in Table 7"1. Dispersion calculations have been made for the eight
model plants described in Chapter 6. Tables 7-2 through 7-10 show the
results of these calculations. [The tables will be shown and discussed in
the final version of the BID]. Maximum downwind concentrations of
micrograms per cubic meter occur at a distance of meters. Further
calculations for the same source controlled by a baghouse give maximum
downwind concentrations of micrograms per cubic meter at a distance
of meters. These concentrations are less than the following Federal
National Ambient Air Quality Standards for particulate matter.1
Primary - 75 microgram per cubic meter - annual geometric mean
Secondary - 260 micrograms per cubic meter - maximum 24-hour
concentration not be be exceeded more than once per year.
For bottom blown furnaces having furnace enclosure options with 80 and
60 percent capture, nationwide annual particulate emissions would be
7-1
-------
TABLE 7-1. U.S. BOPF STEELMAKING CAPACITYC
Year
1979
1980
1981
1982
1983
1984
1985
1986
Total
106 Mg
81.88
-
80.54
81.30
85.78
86.16
84.23
84.54
capacity
106 tons
90.26
-
88.78
89.62
94.55
94.97
92.85
93.19
106
1.32
-
0.49
0.76
4.47
0.38
0.40
0.31
Additions
Mg 106 tons
1.45
-
0.54
0.835
4.931
0.416
0.443
0.339
Retirements
106 Mg TO6 tons
-
-
1.83 2.017
-
-
-
2.32 2.554
-
Reference: Draft Report.
7-2
-------
reduced by a maximum of 60,000 and 45,000 Mg (66,400 and 49,800 tons),
respectively.
Reduction of emissions from BOPF operations are offset by increased
emissions from electric power produced to operate the BOPF secondary
emission control system. Table 7-11 shows power plant emissions for each
model plant and each regulatory alternative. As shown, these emissions are
small in comparison with the total shop emissions shown in Table 6-2.
Control by furnace enclosure gives power plant emissions from about 0.1 to
1.6 percent of total shop emissions. Table 7-12 shows potential nationwide
particulate emission reductions resulting from control of secondary
emissions from hot metal transfer, hot metal charging, tapping, and teeming.
Particle size data for secondary emissions are given in Chapter 3.
Reduction of secondary particulate emissions from BOPFs would also reduce
organic and inorganic emissions. For the hot metal addition phase
associated with a 233 Mg (257 ton) Q-BOPF charge, uncontrolled organic
emissions have been measured as 64.1 mg/m3.2 About 50 percent of the
emissions were associated with particle sizes of less than 3 |jm. Fused
aromatics, amines, and carboxylic acid were present.
Under the assumptions of the furnace enclosure and building evacuation
regulatory alternatives, concentration of these organics would be reduced
to between 0 and 25.6 mg/m3.
Uncontrolled inorganic emissions during the hot metal addition include
nickel, iron, chromium, calcium, arsenic, lead, sulfur and phosphorus, as
shown in Table 7-13. The aggregate concentrations of these elements would
be reduced to between 0 and 63.6 mg/m3 depending on the regulatory
alternative used.
7.2 WATER POLLUTION IMPACT
Potential water pollution impacts include:
1. Pollution from particle scrubber effluents.
2. Pollution from leachate from solid waste disposal sites.
Primary collection systems using a scrubber collect emissions of about
15,300 g/Mg (30.6 Ibs/ton) of steel produced.4 These emissions become
sludge cake removed from a scrubber water cleanup system. Secondary
emissions (hot metal transfer, charging, tapping, and teeming) amount to a
maximum of about 915 g/Mg (1.83 Ibs/ton) of steel produced. If all 915 g
7-3
-------
TABLE 7-11. POWER PLANT ENERGY REQUIREMENTS AND PARTICULATE EMISSIONS
ATTRIBUTABLE TO BOPF SECONDARY EMISSION CONTROL
Model
plant
Ad
B,De
C,E,Hf
Fg
Gh
Secondary emission control system
energy requirements, 106 kWh/yr
Alternative
1
0
0
0
0
0
2 3
11.46 64.9
7.65
14.32 47.7
7.65 42.8
5.09
Power plant
from energy
Al
1
0
0
0
0
0
parti cul ate emissions
production, tons/yr
ternativec
2 3
5.72 32.53
3.82
7.15 23.8
3.82 21.3
2.55
Fan power in kW = 0.000218 (acfm)(in. water pressure drop), Reference 9,
bp. 3-15.
Assumes 0.001 Ibs of particulate per kWh.
Alternatives 1, 2, and 3 are uncontrolled, furnace enclosures, and building
.evacuation, respectively.
Based on 600,000 acfm at 150° F, 10 in. water pressure drop
per year for furnace enclosure; 3,398,023 acfm at 125°F, 10
drop, and 8,760 hours per year for building evacuation.
Based on 600,000 acfm at 150° F, 10 in. water pressure drop
fper year.
Based on 750,000 acfm at 150° F, 10 in. water pressure drop, and 8,760 hours
per year for furnace enclosure; 2,501,412 acfm at 125° F, 10 in. water
pressure drop, and 8,760 hours per year for building evacuation.
^Based on 400,000 acfm at 150° F, 10 in. water pressure drop, and 8,760 hours
per year for furnace enclosure; 2,236,123 acfm at 125° F, 10 in. water
.pressure drop, and 8,760 hours per year for building evacuation.
Based on 400,000 acfm at 150° F, 10 in. water pressure drop, and 5,840 hours
per year.
and 8,760 hours
in. water pressure
and 5,840 hours
7-4
-------
TABLE 7-12. POTENTIAL NATIONWIDE REDUCTION IN PARTICULATE EMISSIONS
FROM SECONDARY EMISSION CONTROL
a
Estimated new BOPF .
steel making capacity
Year 106 Mg/yr 106 tons/yr
1981 0.49 0.54
1982 0.76 0.835
1983 4.47 4.931
1984 0.38 0.416
1985 0.40 0.443
1986 0.31 0.339
1981-86 6.81 7.50
Potential emission reductions .
Top blown Bottom blown
Mg/yr Tons/yr Mg/yr Tons/yr
225 248 448 494
350 384 695 764
2,056 2,268 4,090 4,512
175 191 348 381
184 204 366 405
143 156 284 310
3,133 3,450 6,231 6,863
Based on new shops with 300 ton furnaces producing 3.2 million tons per year
of steel, and equipped with furnace enclosures capturing 100 percent of fume
.generated.
Reference: Draft Report.
cMg/yr x 460 g/Mg x 1 Mg/(l x 106 g), or tons/yr x 0.92 Ibs/ton x
.1 ton/2,000 Ibs.
QMg/yr x 915 g/Mg x 1 Mg/(l x 106 g), or tons/yr x 1.83 Ibs/ton x
1 ton/2,000 ]bs.
7-5
-------
TABLE 7-13. UNCONTROLLED INORGANIC EMISSIONS FROM HOT METAL ADDITION
TO A Q-BOPFa
Concentration- in Off-gas from Q-BOPF
Element mg/m3
Nickel 0.18
Iron 85.3
Chromium 0.26
Calcium 64
Arsenic 0.021
Lead 0.15
Sulfur 7.9
Phosphorous 0.53
158.34
^Reference 2, pp. 22, 30-32.
During hot metal addition only; about 1 minute of each production cycle.
Total particle concentration = 1298 mg/m3.
7-6
-------
(1.83 Ibs) become sludge cake, the loading of particles from scrubber
effluents in the BOPF shop water effluent would increase by only 6.0
percent, and would be a much smaller percentage of the entire steel mill
effluent stream.
Under the draft 1983 effluent regulations,5 BOPF operations will be
limited to suspended solids of 0.0052 kg/Mg of product (BATEA—Best
Available Technology Economically Achievable). Using the BOPF projected
capacity figures mentioned under 7.1 the increased amount of allowable
suspended solids from 1981 to 1986 would be 35 Mg (39 tons) nationwide.
Using the above 6.0 percent, allowable suspended solids from secondary
emissions would increase 2.1 Mg (2.3 tons) nationwide at the end of the
period to 27.2 Mg (30.0 tons) from 25.1 Mg (27.7 tons).
Because most secondary emission collection systems do not use
scrubbers, the 6.0 percent mentioned above represents an upper limit, with
about 0.5 percent being a more reasonable number for BOPF effluents, and
much less for the entire steel mill effluents.
The steel industry most often disposes of collected dusts and sludge
cake by trucking to landfill or similar disposal sites. Leachate from
unprotected dump sites represents a potential water pollution problem.
Aqueous solubility test results for BOPF dusts from baghouses and a
precipitator are shown in Table 7-14.6 These tests indicate that leaching
could produce harmful levels of oil, phenols, cadmium, chromium, and lead.
In regard to secondary emission control, the magnitude of the problem would
increase by no more than the above mentioned 6.0 percent. This statement
is made with the assumption that all secondary emissions are collected and
added to existing landfill operations. Potential problems with dust
disposal practices are being investigated under Resource Conservation &
Recovery Act (RCRA) guidelines.
Techniques for preventing adverse effects from leaching include waste
dump stabilization to prevent leaching, use of dump site liners to contain
leachate, and selection of dump sites having natural barriers to the flow
of leachate into aquifers. The above methods are also effective for
controlling runoff. Water impacts would be so small in comparison to the
rest of the steel mill that preventive action for BOPF emissions would be
taken as part of the overall mill operation.
7-7
-------
TABLE 7-15. EXPECTED ENERGY INCREASE FOR SECONDARY EMISSION CONTROL SYSTEMS, 1981-1986'
Alternative
Greatest increase
Top blown Bottom blown
Least increase
Top blown Bottom blown
Uncontrolled 0000
Furnace enclosure 38.2 x 106 kWh/yrb 33.6 x 106 kWh/yrc 26.9 x 106 kWh/yrd 33.6 x 106 kWh/yrc
Building evacaution 214 x 106 kWh/yrb 112 x 106 kWh/yrc 152 x 106 kWh/yrd 112 x 106 kWh/yrc
aCapacity increase, 1981-1986, projected at 6.81 million Mg/yr (7.50 million tons/yr),
Draft Document. Energy increases calculated from: (7.50 million tons/yr)/(Model plant production
rate, ton/yr) x Energy requirement for model plant from Table 7-11. Energy increases for primary
emission control systems can be calculated from: 0.000218 (175,000 acfm) (65 in. water pressure
drop) (8,760 hr/yr) = fan power in kWh/yr, + (7.15 gal/1000 scf) (488 scf/vessel) (300 ton vessel)
(0.12 hp/gpm) (0.7457 kW/hp) (8,760 hr/yr) = pumping power in kWh/yr. Energy increase = 22.6 x 106
kWh/yr for 3.2 x 106 tons/yr, or 53.0 x 106 kWh/yr for 7.50 x 106 tons/yr. These equations are taken
.from Table 7-11, reference 9, and 10.
DBased on Model F.
E, or H.
.Based on Model C,
Based on Model A.
-------
TABLE 7-16. SUMMARY OF ENVIRONMENTAL IMPACTS - BOPF SECONDARY EMISSIONS
Emission factors: 460 g/Mg (0.92 Ib/ton) of steel; top blown; hot metal transfer, charging, tapping,
and teeming
(Uncontrolled) 915 g/Mg (T.83 Ib/ton) of steel; bottom blown; hot metal transfer, charging,
tapping, and teeming
BOPF capacity:
Potential
Air Emissions: If Top Blown
.(Uncontrolled) If Bottom Blown1
Potential
Water Emissions:
(Under effluent regulations
for 1983)
Potential:
Solid Wastes:
Energy Estimates:
(Required by secondary
emission collection)
Lowest
Highest
1981
80.5 x 106 Mg/yr
88.8 x 106 tons/yr
37,057 Mg/yr
(40,848 tons/yr)
73,712 Mg/yr
(81,252 tons/yr)
25.1 Mg/yr
(27.7 tons/yr)
1986
84.5 x 106 Mg/yra
93.2 x 106 tons/yr
38,893 Mg/yr
(42,872 tons/yr)
77,364 Mg/yr
(85,278 tons/yr)
27.2 Mg/yr
(30.0 tons/yr)
New capacity, 1981-1986
6.81 x 106 Mg/yr
7.50 x 106 tons/yr
3,133 Mg/yr .
(3,450 tons/yr)
6,231 Mg/yr
(6,863 tons/yr)
2.1 Mg/yr
(2.3 tons/yr)
Same as Air Emissions (assumes 100 percent control of air emissions
and all dust landfilled).
26.9 x 106 kWh/yr
214 x 106 kWh/yr
^Disagrees with new capacity because of retired equipment.
Most existing capacity is top blown.
-------
(10 in., 1 in., and 65 in. water column), respectively. Actual savings
would be minimal, however, since few secondary emission control systems
would be expected to use scrubbers.
A second method of reducing energy consumption would be to recover
heat values from hot gases produced during charging and tapping. This
recovery would be minimal, however, since major heat evolution occurs
during blowing. During the primary emission phase heat recovery from water
cooled, open hoods would yield about 167,000 kg/Mg of steel, while carbon
monoxide recovered from suppressed combustion systems would produce about
420,000 kg/Mg of steel.8 European practice has been to recover CO for its
fuel value in some installations, but U.S. practice has been to flare the
CO. Recovery of 420,000 kj/Mg of steel for 6.18 x 106 Mg (6.81 x 106 tons)
of steel would amount to 2.6 x 1012 kj more heat recoverable in 1986 than
in 1981 from primary control.
7.5 OTHER ENVIRONMENTAL IMPACTS
Control of secondary emissions will not require new types of equipment.
Volume of noise generated will increase in proportion to new BOPF furnaces
built, but noise intensity will not increase, and may decrease as new
equipment designs, such as less noisy air compressors, come on the market.
7.6 OTHER ENVIRONMENTAL CONCERNS
One effect of promulgating an NSPS for secondary BOPF emissions may be
to lengthen operating lifetimes of existing shops. As long as existing
equipment is continued in service it will produce secondary (and primary)
emissions at a rate determined by the difference between Federal NSPS and
state and local standards for existing sources. The increased lifetimes of
existing shops would come about from diversion of capital from purchasing
steel production facilities to purchasing particulate control equipment.
This long-term loss is expected to be minor.
Environmental impacts are summarized in Table 7-16.
7.7 REFERENCES
1. U.S. Environmental Protection Agency. Code of Federal Regulations.
Title 40, Chapter I, subchapter C, part 50. Washington, D.C. Office of
the Federal Register. July 1977.
7-12
-------
2. Westbrook, C. W. Level 1 Assessment of Uncontrolled Q-BOP Emissions.
Research Triangle Institute. EPA-600/2-79-190. September 1979. p. 3, 4,
3. Analysis of Economic Effects of Environmental Regulations on the
Integrated Iron and Steel Industry. Volume II. (Draft Report).
Temple, Barker & Sloane, Inc. Welles ley Hills, Massachusetts.
EPA-230/3-76-014b. December 1976.
4. Cuscino, Thomas A., Jr. Particulate Emission Factors Applicable to the
Iron and Steel Industry. Midwest Research Institute. EPA-450/4-79-028.
September 1979. p. 56.
5. Development Document for Interim Final Effluent Limitations Guidelines
and Proposed New Source Performance Standards for the Forming, Finishing
and Specialty Steel. U.S. Environmental Protection Agency.
EPA 440/1-76-048b. March 1976.
6. Baldwin, V. H., et al. Environmental and Resource Conservation
Considerations of Steel Industry Solid Waste. Research Triangle
Institute. EPA-600/2-79-074. April 1979. p. 97.
7. Reding, John T. and B. P. Shepherd. Energy Consumption: The Primary
Metals and Petroleum Industries. Dow Chemical, U.S.A., Texas Division.
EPA-650/2-75-032-b. April 1975.
8. Dixon, T. E. Capital and Operating Costs of OBM/Q-BOP Gas Cleaning
Systems. Iron and Steel Engineer. 55:37-41. March 1978.
9. Development of Air Pollution Control Cost Functions for the Iron and
Steel Industry. PEDCo Environmental, Inc. Cincinnati, Ohio.
EPA-450/1-80-001. July 1979. p. 3-15, C-3.
10. Neveril, R. B. Capital and Operating Costs of Selected Air Pollution
Control Systems. Gard, Inc. EPA 450/5-80-002. December 1978.
p. 4-51, 4-63.
7-13
-------
8. COSTS
8.1 COST ANALYSIS OF REGULATORY ALTERNATIVES
Tables 8-1 through 8-5 give cost information for the model plants
described in Chapter 6.
8.1.1 New Facilities
Costs for secondary emission control systems are based on baghouses
with the design criteria shown in Table 8-6. For these tables it is assumed
that no water pollution control or hot metal transfer and skimming control
are required for shops in which a new vessel is added to existing vessels.
Only the new vessel must be controlled, and it is unlikely that water
pollution control equipment would be needed in addition to that already
existing in the plant, since scrubbers are not ordinarily used for secondary
emission control. For KMS conversions (Model E), it is also assumed that
existing primary emission control equipment is sufficient. Chapter 5 gives
further discussion of the KMS conversion in Section 5.2.1.2. Conversion
from an open hearth shop to a BOPF shop requires primary and secondary
emission control equipment as well as water pollution control, and hot
metal transfer and skimming control equipment. Solid waste disposal costs
for all models are included in the secondary emission system annual costs
of control. The Chemical Engineering Plant Cost Index was used to adjust
costs given in the references for Tables 8-1 through 8-5.
Design criteria given in Table 8-6 were derived as conservative
estimates based on typical specifications for existing installations.
Cost relationships for secondary emission control are given in Table
8-7. These relationships are shown as percentages of total cost represented
by secondary control systems or by total pollution control equipment. For
secondary pollution control investment in furnace enclosures the range is
about 10 to 14 percent for greenfield shops, and 14 to 19 percent for
roundout shops. The KMS conversion, however, has a cost of about 60 percent
because plant investment for the conversion is small compared to greenfield
plant investment. For building evacuation the range of investments is
about 25 to 35 percent depending on vessel size and location of blowing.
8-1
-------
TABLE 8-1. CAPITAL COSTS OF CONTROL BY FURNACE ENCLOSUREa~BOPF SECONDARY EMISSIONS-MILLIONS OF DOLLARS (JULY I960)1 2
Case Model
Primary Water Secondary
pollution pollution pollution
Plant control . control control
investment investment investment investment
Hot metal transfer
and skimming
pollution control
investment
Total
pollution
control
investment
CO
ro
Two new 300 ton vessels, 169.6
closed hood, top blown
equipped with furnace
enclosure and baghouse.
Production 3,200,000
tons per year
One new 300 ton vessel 105.3
added to two existing
300 ton vessels, closed
hoods, top blown, equipped
with furnace enclosure and
baghouse. Production
5,900,000 tons per year.
Two new 300 ton vessels, 169.6
closed hood, bottom blown,
equipped with furnace
enclosure and baghouse.
Production 3,200,000 tons
per year.
One new 300 ton vessel 105.3
added to two existing
300 ton vessels, open
hood, top blown,
equipped with baghouse.
Production 5,900,000
tons per year.
13.2
6.6
13.2
4.0
4.7
4.7
21.7
18.2
24.8
18.2
1.7
1.7
41.3
24.8
44.4
19.2
(Continued)
-------
TABLE 8-1. (CONTINUED)
Case Model
Primary Water Secondary
pollution pollution pollution
Plant control b control control
Investment investment Investment investment
Hot metal transfer
and skimming
pollution control
investment
Total
pollution
control
investment
00
CJ
E Two existing 300 ton 16
vessels converted to KMS
process, closed hood, top
and bottom blown, equipped
with furnace enclosure and
baghouse. Production
3,200,000 tons per year.
F. Two new 150 ton vessels, 84.8
closed hood, top blown,
equipped with furnace
enclosure and baghouse.
Production 1,600,000
tons per year.
G One new 150 ton vessel 50.7
added to two existing
150 ton vessels, closed
hood, top blown, equipped
with furnace enclosure
and baghouse. Production
2,900,000 tons per year.
9.4
4.7
24.8
24.8
3.1
15.5
1.4
29.4
12.9
17.6
(Continued)
-------
TABLE 8-1. (CONTINUED)
Primary Water Secondary Hot metal transfer Total
pollution pollution pollution and skimming pollution
Plant control . control control pollution control control
Case Model investment investment investment investment Investment investment
H Two new 300 ton vessels, 99.8 13.2 4.7 24.8 1.7 44.4
closed hood, bottom blown
equipped with furnace
enclosure and baghouse.
Conversion of an open
hearth shop to basic
oxygen process.
Production 3,200,000
tons per year.
^Includes direct and indirect capital costs.
Assumes separate control device for closed hood, and common control device for open hood.
^For BAT 2 control.
Assumes same control device as secondary emission control.
-------
TABLE 8-2. ANNUAL COSTS OF CONTROL BY FURNACE ENCLOSUREa~BOPF SECONDARY EMISSIONS-MILLIONS OF DOLLARS (JULY 1980)1
Case
A
Primary
pollution
control b
Model $/yr (annual $/ton)
Two new 300 ton vessels, closed hood, 4.19 (1.31)
Water
pollution
control b
$/yr (annual $/ton)
0.67 (0.21)
Secondary
pollution
control L
$/yr (annual $/ton)
5.15 (1.61)
Hot metal transfer
and skimming
pollution control .
$/yr (annual $/ton)
0.51 (0.16)
CO
Ul
top blown equipped with furnace
enclosure and baghouse. Production
3,200,000 tons per year.
One new 300 ton vessel added to two
existing 300 ton vessels, closed
hoods, top blown, equipped with
'furnace enclosure and baghouse.
Production 5,900,000 tons per
year.
Two new 300 ton vessels, closed
hood, bottom blown, equipped
with furnace enclosure and bag-
house. Production 3,200,000
tons per year.
One new 300 ton vessel added to
two existing 300 ton vessels,
open hood, equipped with bag-
house. Production 5,900,000
tons per year.
Two existing 300 ton vessels
converted to KMS process,
closed hood, top and bottom
blown, equipped with furnace
enclosure and baghouse.
Production 3,200,000 tons
per year.
3.07
4.19
0.89
(0.52) 0
(1.31) 0.67
(0.15) 0
4.37
(0.21) 5.92
4.37
5.92
(0.74)
(1.85) 0.51
(0.74)
(1.85)
(0.16)
(Continued)
-------
TABLE 8-2. (CONTINUED)
CO
Case Model
F Two new 150 ton vessels, closed
Primary
pollution
control .
$/yr (annual $/ton)
3.02 (1.89)
Water
pollution
control .
$/yr (annual $/ton)
0.45 (0.28)
Secondary
pollution
control .
$/yr (annual $/ton)
3.65 (2.28)
Hot metal transfer
and skimming
pollution control .
$/yr (annual $/ton)
0.45 (0.28)
hood, top blown, equipped with
furnace enclosure and baghouse.
Production 1,600,000 tons per
year.
One new 150 ton vessel added to
two existing 150 ton vessels,
closed hood, top blown, equipped
with furnace enclosure and bag-
house. Production 2,900,000 tons
per year.
Two new 300 ton vessels, closed
hood, bottom blown equipped with
furnace enclosure and baghouse.
Conversion of an open hearth shop
to basic oxygen process.
Production 3,200,000 tons per
year.
2.20
4.19
(0.76)
(1.31)
0.67
(0.21)
3.10
5.92
(1.07)
(1.85)
0.51
(0.16)
.Includes fixed capital charges.
Per ton of total shop production.
-------
TABLE 8-3. CAPITAL COST OF CONTROL BY BUILDING EVACUATION3—BOPF SECONDARY EMISSIONS—MILLIONS OF DOLLARS (JULY I960)1 2
00
Model
Two new 300 ton vessels,
closed hood, top blown
Production 3,200,000
tons per year
Two new 300 ton vessels,
closed hood, bottom blown.
Production 3,200,000 tons
per year.
Two new 150 ton vessels,
closed hood, top blown.
Production 1,600,000
tons per year.
Primary
pollution
Plant control .
Investment Investment
169.6 13.2
169.6 13.2
84.8 9.4
Water
pollution
control
Investment
4.7
4.7
3.1
Secondary
pollution
control
Investment
64.5
49.6
45.1
Hot metal transfer
and skimming
pollution control
investment
1.7
1.7
1.4
Total
pollution
control
Investment
84.1
69.2
59.0
.Includes direct and Indirect capital costs.
Assumes separate control device for closed hood, and common control device for open hood.
^For BAT 2 control.
Assumes same control device as secondary emission control.
-------
TABLE 8-4. ANNUAL COSTS OF CONTROL BY BUILDING EVACUATION--BOPF SECONDARY EMISSIONS—MILLIONS OF DOLLARS (JULY 1980)1 2
Mode]
Primary
pollution
control
Water
pollution
control
$/yr (annual $/ton) $/yr (annual $/ton)
Secondary
pollution
control *,
$/yr (annual $/ton
Hot metal transfer
and skimming
pollution control.
$/yr (annual $/tonJ
Two new 300 ton vessels, closed hood,
top blown equipped with furnace
enclosure and baghouse. Production
3.200,000 tons per year.
Two new 300 ton vssels, closed
hood, bottom blown, equipped
with furnace enclosure and bag-
house. Production 3,200,000
tons per year.
Two new 150 ton vessels, closed
hood, top blown, equipped with
Co furnace enclosure and baghouse.
oo Production 1,600,000 tons per
year.
4.19
4.19
3.02
(1.31)
0.67
(1.31) 0.67
(1.89) 0.45
(0.21)
16.51
(5.16)
0.51
(0.21) 12.58 (3.93) 0.51
(0.28) 11.42 (7.14) 0.45
(0.16)
(0.16)
(0.28)
.Includes fixed capital charges.
Per ton of total shop production.
-------
TABLE 8-5. BOPF SHOP ANNUAL OPERATING COSTS (106 JULY 1980 DOLLARS/YR)3
Caseb A, C, H
Scrap
Hot Metal d
Operating Labor
Labor Overhead
Electric Power
Water
Fuel
Other Raw Material
CO
to Maintenance
130.
0
22.
39.
3.
1.
1.
36.
19.
Total 255.
Scrap Credit
Energy Credit^
Net Costh
$/Ton
8.
0
246.
77.
43
43
71
90
25
86
29
26
13
16
97
18
Case B, D
Total Addedc
240.48
0
33.65
59.57
7.20
2.30
3.42
66.91
32.75
446.28
15.05
0
431.23
73.09
110.05
0
11.22
19.86
3.29
1.05
1.57
30.62
13.48
191.14
6.89
0
184.25
68.24
fDoes not include environmental control annual costs.
Cases for plants described for capital cost of control by
^Added annual operating cost for modification.
Assumes costs of hot metal arc charged to prior operations
are estimated to be $ /ton of hot metal or $
Case E
Total Addedc
130.05
0
22.43
39.71
3.90
1.25
1.86
36,29
19.26
255.13
8.16
0
246.97
77.18
hooding,
such as blast
/ton of raw
0
0
0
0
0
0
0
0
0
0
0
0
0
0
furnace, coke
BOPF steel.
Case F
65.
0
17.
31.
1.
0;
0.
18.
9.
146.
4.
0
142.
88.
22
95
77
95
,62
93
14
63
21
08
13
83
ovens, etc.
Case G .
Total Added0
118.
0
26.
47.
3.
1.
1.
32.
16.
248.
7.
0
240.
83.
Hot metal
20
92
65
54
13
68
89
37
38
40
98
10
52.99
0
8.97
15.88
1.59
0.51
0.75
14.74
6.74
102.17
3.32
0
98.85
76.04
production costs
Bother raw materials include fluxes, additives, and oxygen.
Credit for ingot scrap.
fjwhere BOPF hoods produce useful steam there could be a credit for steam.
Credit for collected dust of about $0.18/ton of raw BOPF steel not included.
-------
TABLE 8-6. DESIGN CRITERIA FOR MODEL PLANT
SECONDARY EMISSION CONTROLS SYSTEMS3
Gas volume Operating time for
Model Regulatory alternative acfm affected unit, hr/yr
A Furnace enclosure 600,000 8,760
Building evacuation 3,398,023 8,760
B,D Furnace enclosure 600,000 7,947
C,H Furnace enclosure 750,000 8,760
Building evacuation 2,501,412 8,760
E Furnace enclosure 750,000 8,760
Building evacuation 2,501,412 8,760
F Furnace enclosure 400,000 8,760
Building evacuation 2,236,123 8,760
G Furnace enclosure 400,000 1,947
Emission control based on fabric filter at air-to-cloth ratio of 2 fpm.
Building evacuation assumes 2.5 minutes per air change. Gas temperatures at
the baghouse are 125° F for building evacuation and 150° F for furnace
enclosures.
8-10
-------
TABLE 8-7. COST RELATIONSHIPS FOR BOPF SECONDARY EMISSION CONTROL
CO
Model plant
A
B
C
0
E
F
G
H
Regulatory alternative
Furnace enclosure
Building evacuation
Furnace enclosure
Furnace enclosure
Building evacuation
Furnace enclosure
Furnace enclosure
Building evacuation
Furnace enclosure
Building evacuation
Furnace enclosure
Furnace enclosure
Building evacuation
Secondary pollution
control investment,
percent of total
plant investment
10.3
25.4
14.0
11.6
20.8
14.6
60.8
75.6
13.6
31.4
18.9
17.2
35.1
Total pollution
control investment,
percent of total
plant investment
19.6
33.2
19.1
20.8
29.0
15.4
60.8
75.6
25.7
41.0
25.8
30.8
45.7
Secondary pollution
control annual costs,,
percent of steel cost
2.09
6.69
1.01
2.40
5.09
1.01
2.40
6.69
2.57
8.03
1.29
2.40
6.69
Total pollution
control annual costs..
percent of steel cost
4.26
8.86
1.73
4.57
7.27
1.22
2.40
6.69
5.33
10.79
2.20
4.57
8.86
?Total plant investment = plant investment + total pollution control investment from Tables 8-1 and 8-3.
These costs are a percentage of the net costs shown in Table 8-5.
-------
Again the KMS conversion appears high (75.6 percent) because of low plant
investment.
For total pollution control investment as a percentage of total plant
investment the percentages range from about 20 to 26 percent for furnace
enclosures for all but KMS conversion, which is 60.8 percent. Building
evacuation control covers a broader range from about 29 to 46 percent.
KMS, again, costs more (75.6 percent) because of low plant investment.
When secondary pollution control annual costs are compared with net
cost of steel produced, furnace enclosures on greenfield shops are about 2
to 2.6 percent, and on roundout shops are about 1 to 1.3 percent. Building
evacuation systems range from about 5 to 8 percent.
Total annual costs of pollution control compared with net cost of
steel are about 4.3 to 5.3 percent and 1.2 to 4.6 percent for furnace
enclosures on greenfield and roundout shops, respectively. Building
evacuation costs are from about 7 to 11 percent.
Costs of secondary pollution control expressed as $/lb or $/ton of
emissions captured are shown in Table 8-8. These costs range from about
$2,300 to $6,700 per ton for greenfield shops with furnace enclosures, and
from about $2,600 to $10,500 for roundout shops with furnace enclosures.
As discussed in Chapter 6, the effectiveness of furnace enclosures on
bottom blown furnaces has not been measured accurately. Three capture
efficiencies (60, 80, and 100 percent) have been used for estimating
purposes, and are included in the ranges given above.
Building evacuation costs are based on two levels of baghouse outlet
loading, 0.003 and 0.01 gr/scf. At the 0.003 gr/scf level, collected
emissions cost from $4,700 to $22,560 per ton and at the 0.01 gr/scf level,
they are from $6,060 to $87,360 per ton. For comparison, the annual
operating costs for a ton of steel are from about $73 to $89 per ton, as
shown in Table 8-5, or $434 per ton for finished steel as shown in Table
9-16.
Table 7-12 shows an estimated increase in new BOPF steelmaking capacity
of 7.50 million tons from 1981 through 1986. This amount is equivalent to
2.3 to 5.8 times model plant production depending on which model plant is
chosen. Capital required to finance secondary pollution control equipment
for the new capacity (in July 1980 dollars) ranges from $50.6 million to
$74.4 million dollars for furnace enclosures, and from $116 million to $212
8-12
-------
TABLE 8-8. COST EFFECTIVENESS OF SECONDARY EMISSION CONTROL
co
i
CO
Model plant
A
B, D
C, H
E
F
G
Secondary
Regulatory alternative
Furnace enclosure
Building evacuation 0.003
0.01
Furnace enclosure
Furnace enclosure (100% capture)
( 80% capture)
( 60% capture)
Building evacuation 0.003
0.01
Furnace enclosure (100% capture)
( 80% capture)
( 60% capture)
Building evacuation 0.003
0.01
Furnace enclosure
Building evacuation 0.003
0.01
Furnace enclosure
emissions collected3
tons/yr
1,159
1,120
189
614
2,571
2,065
1,803
2,671
2,076
2,285
1,779
1,274
2,671
2,076
547
506
0
294
$/yrb
5.15 x 106
16.51 x 106
16.51 x 106
4.37 x 106
5.92 x 106
5.92 x 106
5.92 x 106
12.58 x 106
12.58 x 106
5.92 x 106
5.92 x 106
5.92 x 106
12.58 x 106
12.58 x 106
3.65 x 106
11.42 x 106
11.42 x 106
3.10 X 108
Annual cost of collection
$/lb
2.22
7.37
43.68
3.56
1.15
1.43
1.64
2.35
3.03
1.30
1.66
2.32
2.35
3.03
3.34
11.28
5.27
$/ton
4,440
14,740
87,360
7,120
2,300
2,860
3,280
4,700
6,060
2,600
3,320
4,640
4,700
6,060
6,680
22,560
10,540
^Derived from Tables 6-2 through 6-16.
From Tables 8-2 and 8-4.
-------
TABLE 8-9. COST ESTIMATE FOR OSHA COMPLIANCE--BOPF SECONDARY EMISSIONS
MILLIONS OF DOLLAR (JULY 1980)
Case Model
Plant Investment
Total Pollution
Control Investment OSHA Directed Investment
a
CO
i
Two new 300 ton vessels, 169.6
closed hood, top blown
equipped with furnace
enclosure and baghouse.
Production 3,200,000
tons per year.
One new 300 ton vessel 105.3
added to two existing
300 ton vessels, closed
hoods, top blown, equipped
with furnace enclosure and
baghouse. Production
5,900,000 tons per year.
Two new 300 ton vessels 169.6
closed hood, bottom blown,
equipped with furnace
enclosure and baghouse.
Production 3,200,000 tons
per year.
One new 300 ton vessel 105.3
added to two existing
300 ton vessels, open
hood, equipped with
baghouse. Production
5,900,00 tons per
year.
44.4
27.8
48.1
22.2
6.22
3.89
6.73
3.11
(Continued)
-------
TABLE 8-9 (CONTINUED)
Total Pollution
Case Model Plant Investment Control Investment OSHA Directed Investment
E Two existing 300 ton 16 28.5 3.99
vessels converted to KMS
process, closed hood, top
and bottom blown, equipped
with furnace enclosure and
baghouse. Production
3,200,000 tons per year.
F Two new 150 ton vessels, 84.8 31.6. 4.42
closed hood, top blown,
equipped with furnace
enclosure and baghouse.
Production 1,600,000
tons per year.
G One new 150 ton vessel 50.7 19.8 2.77
i added to two existing
—' 150 ton vessels, closed
01 hood, top blown, equipped
with furnace enclosure
and baghouse. Production
2,900,000 tons per year.
(Continued)
-------
TABLE 8-9 (CONTINUED)
Total Pollution
Case Model Plant Investment Control Investment OSHA Directed Investment
H Two new 300 ton vessels, 99.8 48.1 6.73
closed hood, bottom blown
equipped with furnace
enclosure and baghouse.
Conversion of an open
hearth shop to basic
oxygen process.
Production 3,200,000
tons per year.
aCa.lculated as 14 percent of Total Pollution Control Investment
CO
CTl
-------
million for building evacuation. Annualized costs range from $12.05 million
to $17.89 million dollars for furnace enclosures, and from $29.44 million
dollars to $53.56 million for building evacuation.
8.1.2 Modi f ied/Reconstructed Faci1ities
The KMS process can be used for either new or modified vessels. This
process has been discussed in Section 8.1.1. Open hearth conversion has
also been discussed in Section 8.1.1.
8.2 OTHER COST CONSIDERATIONS
In addition to cost of control for secondary emissions, there are
other regulatory costs mandated under Occupational Safety & Health Act
(OSHA), Water Pollution Control Act (WPCA) and Resource Conservation &
Recovery Act (RCRA).
The Office of Technology Assessment3 shows estimates that OSHA
investment costs are about 14 percent of EPA costs on an industry-wide
basis. Applying this percentage to BOPF secondary emission control options
gives the results shown in Table 8-9.
Water pollution control costs would apply to effluents from scrubbers.
These costs have been shown in Table 8-1, and range from 9.8 to 10.6 percent
of total pollution control investment for new facilities.
There are no existing regulations for RCRA applicable to BOPF shops.
Promulgation of a standard for BOPF secondary emission control is not
expected to impose major resource requirements on regulatory and enforcement
agencies since the agencies are already maintaining surveillance over BOPF
shops for primary emission control.
8.3 REFERENCES
1. Analysis of Economic Effects of Environmental Regulations on the
Integrated Iron and Steel Industry. Volume II. (Draft Report).
Temple, Barker & Sloane, Inc. Wellesley Hills, Massachusetts.
EPA-230/3-76-014b. December 1976.
2. Development of Air Pollution Control Cost Functions for the Integrated
Iron and Steel Industry. PEDCo Environmental, Inc., Cincinnati, Ohio.
EPA-450/1-80-001. July 1979.
3. Office of Technology Assessment. Technology and Steel Industry
Competitiveness. June 1980. p. 349.
8-17
-------
9. ECONOMIC IMPACTS
This chapter discusses the economic impacts of the regulatory alterna-
tives. Section 9.1 presents a profile of the steel industry. Information
from this section is used in the economic impacts analysis, which is dis-
cussed in Sections 9.2 and 9.3. The analysis showed that under Regulatory
Alternative II prices would rise by 0.3 to 1.1 percent if all additional
control costs were passed on to the consumer. As a result, the quality of
steel demanded would decline by 0.3 to 1.5 percent. If producers absorbed
all additional control costs, the rate of return on an integrated mill
would range from 4.9 to 5.5 percent compared to its baseline level of
6;. 2 percent. The maximum incremental annualized cost of compliance with
Alternative II was estimated to range from $21 million to $33 million.
9.1 INDUSTRY PROFILE
9.1.1 Introduction
Iron and steel producers shipped products valued at $41.9 billion in
1977 which amounted to 2.2 percent of total GNP. With 441,400 employees,
2.3 percent of all manufacturing employment, the industry accounted for 3.1
percent of the total value of manufacturing shipments. Value added by the
349,900 production workers was $15.0 billion, 2.6 percent of the total for
all manufacturing. The industry spent $2.2 billion on new plants and
equipment, 4.5 percent of all manufacturing expenditures. Summary statis-
tics for the iron and steel industry are presented in Table 9-1.
This section focuses on the industry identified by the Standard Indus-
trial Classification (SIC) Code 3312, Blast Furnaces (including coke ovens),
Steel Works, and Rolling Mills. Data on the production of iron in blast
furnaces and data on the production of steel in all steel making furnaces
are classified in this industry. Because steel furnaces are usually inte-
grated with casting and rolling facilities at the same plant, SIC 3312 also
9-1
-------
TABLE 9-1. GENERAL STATISTICS FOR THE IRON AND STEEL INDUSTRY1
Year
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
Number
of
plants
329
NA
NA
NA
NA
364
NA
NA
NA
NA
518
Employees
(1,000)
533.1
533.1
537.7
526.5
482.2
469.1
502.1
518.0
451.3
451.9
441.4
Production
workers
(1,000)
434.0
432.9
436.4
424.7
385.0
379.3
409.9
412.3
354.8
358.0
349.9
Payroll3
4,385.3
4,719.7
5,092.9
5,060.3
4,968.9
5,537.8
6,480.9
7,513.2
7,076.4
8,041.7
8,717.0
Industry
shipments
19,620.6
21,161.1
22,299.0
21,501.6
21,971.3
23,946.7
30,365.8
41,671.7
35,659.8
39,684.1
41,897.8
Value
added3
8,910.1
9,275.8
9,853.2
9,350.5
9,563.1
10,304.7
12,769.4
17,425.8
13,356.2
14,755.5
15,021.4
Capital
expenditures3
1,661.0
1,794.7
1,574.5
1,329.9
1,005.4
961.2
1,110.5
1,643.4
2,068.0
2,142.3
2,155.7
Gross
assets
21,524.5
22,654.5
24,707.1
25,850.4
26,486.7
27,083.3
28,018.4
29,395.6
30,880.5
32,645.8
33,586.1
NA = Not available.
aln millions of current dollars.
-------
includes data on the output of steel mill products from integrated plants.
Table 9-2 shows production of iron and steel mill products between 1968 and
1978.
The ten industries which consumed the largest amounts of steel mill
products in 1979 are shown in Table 9-3. The automotive industry consumed
the largest portion of total production, 18.6 percent. Steel service
centers buy large quantities of steel products (18.2 percent of the total
in 1979) for resale in smaller lots to consumers of steel products who
represent many industries. Sales to construction, machinery, and other
capital goods industries amounted to another 36.7 percent of all steel
shipments.
Until 1910 almost all raw steel was produced by the Bessemer Con-
verter. With depletion of high purity (low phosphorous) iron ore from the
Mesabi range that was critical to the Bessemer process, new steelmaking
processes were developed to use the lower purity, taconite ores available
from Minnesota. The amount of steel produced in the Bessemer furnace
declined steadily until the process was discarded altogether after 1968.
The open hearth furnace replaced the Bessemer Converter and for more
than fifty years accounted for the largest percentage of raw steel production.
Air pollution problems and high production and capital costs contributed to
its accelerating decline after the introduction of the basic oxygen furnace
in the 1950's. By 1979 the open hearth produced only 14 percent of total
raw steel output compared to 50.1 percent in 1968 and 90.0 percent in 1955.
(See Table 9-4.)
The basic oxygen furnace (BOPF) was introduced in this country in 1953,
shortly after the domestic steel industry had completed its postwar modern-
ization program. As a result, its acceptance came slowly; by 1960 only 3.4
percent of raw steel output came from the BOPF process. As open hearth
facilities wore out and as the industry expanded, high capacity BOPF facil-
ities were installed. In 1970, BOPF steel production overtook open hearth
steel production, accounting for 48.2 percent of total raw steel, and by
1979 BOPF's produced 61.1 percent of total raw steel output. Lower capital
and production costs and lower pollution emissions, compared to open hearth
furnaces, contributed to the increase in use of the BOPF during this period.
A modification of the BOPF process, called Q-BOPF, shows promise for replacing
large open hearth facilities as they deteriorate.
9-3
-------
TABLE 9-4. RAW STEEL PRODUCTION BY FURNACE AND CAPACITY UTILIZATION
(thousand tonnes)4
Year
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
Basic
oxygen
furnace
44,282
54,645
57,452
58,008
67,662
75,532
73,983
65,137
72,500
70,223
75,735
75,529
Electric
arc
furnace
15,253
18,263
18,291
18,997
21,519
25,183
26,008
20,575
22,328
25,294
29,245
30,778
Open
hearth
furnace
59,725
55,242
43,565
32,259
31,693
36,088
32,204
20,104
21,292
18,183
19,332
17,380
Total
production
119,260
128,151
119,308
109,264
120,874
136,803
132,195
105,816
116,120
113,700
124,312
123,687
Capacity3
141,136
140,825
141,193
141,901
140,551
140,311
141,385
138,866
143,607
144,968
143,244
140,886
Capacity
utilization
(%)5
84. 5b
91. Ob
84. 5b
77. Ob
86. Ob
97. 5b
93. 5b
76.2
80.9
78.4
86.8
87.8
Estimated by dividing production by utilization.
'Estimated. Data on capacity not regularly collected before 1975.
9-4
-------
TABLE 9-2. PRODUCTION OF COKE, PIG IRON, RAW STEEL, AND STEEL
MILL PRODUCTS, SIC 3312, 1968-1979
(thousand tonnes)2
Year
Coke
Pig iron
Raw steel
Steel mill
products
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
51,700.4
52,802.2
54,228.4
46,698.5
48,247.4
53,148.9
50,086.0
46,770.4
48,228.6
43,643.1
40,873.4
44,003.4
80,539.9
86,198.0
82,948.4
73,753.2
80,686.8
91,477.8
87,007.2
72,504.9
78,807.1
73,779.5
79,541.0
78,927.8
119,260.3
128,150.7
119,307.5
109,264.0
120,874.2
136,802.6
132,194.9
105,815.8
116,119.6
113,700.2
124,312.4
123,687
83,058.2
85,163.8
82,370.6
78,959.5
83,284.1
101,087.6
99,311.3
72,535.8
81,144.9
82,687.2
88,845.1
90,956.2
9-5
-------
TABLE 9-3. SHIPMENTS OF STEEL MILL PRODUCTS BY MARKET
CLASSIFICATION 1979
(thousand tonnes)3
Market
Automotive
Steel service centers
Construction and contractors
Machines, equipment, and tools3
Containers and packaging
Converting and processing
Rail transportation
Oil and gas industry
Exports
All other shipments
Total 1979
Shipments
16,893
16,552
12,449
9,785
6,143
4,588
3,729
3,392
2,450
14,975
90,956
Percent
of total
18.6
18.2
13.7
10.8
6.8
5.0
4.1
3.7
2.7
16.4
100.0
Includes agriculture and electrical machinery.
9-6
-------
The adaptation of the electric arc furnace to the production of carbon
steel led steel makers to produce a greater percentage of raw steel by this
process and facilitated entry of smaller firms into steel production. The
furnaces cost less than BOPFs and are independent of blast furnaces and
coking ovens since they operate efficiently with a charge of 100 percent
scrap. The development of continuous casting helped the electric furnace
to gain a 24.9 percent share of raw steel production in 1979. Mini-mills,
consisting of an electric arc furnace supplying molten metal to a continuous
caster, have become the fastest growing segment of the steel industry.
This profile characterizes the steel industry in terms of its basic
conditions, its structure, the conduct that derives from the structure, and
the financial performance of its business conduct. Section 9.1.2 describes
the production and consumption of steel output, raw material inputs, and
policy constraints. Section 9.1.3 analyzes the elements of market structure
as they relate to industry conduct. Aspects of this conduct are discussed
in Section 9.1.4. The results of business decisions based on the above
conditions are analyzed and possible future trends are presented in the
performance section, 9.1.5.
9.1.2 Supply
9.1.2.1 Production Technology.6 Steel production involves 4 stages:
(1) pig iron production, (2) raw steel production, (3) semifinishing, and
(4) finishing of steel mill products.
Steel mills which use either BOPFs or open hearth furnaces usually are
also integrated into the production of coke and pig iron. Coke is the
carbon residue left over from the heating of coal in the absence of oxygen.
In the blast furnace, it supplies fuel to heat iron ore and chemically
reduces the iron ore to iron. Producers shipped 16.8 million tonnes of
coke in 1977 valued at $.1.6 billion, which was 37.6 percent of total coke
production. Integrated plants produced 29.3 million tonnes which was used
in blast furnaces on site.
Coke, iron ore, and limestone are converted in the blast furnace to
pig iron. Limestone and other fluxes, such as dolomite, remove most impu-
rities from iron ore before the coke is added. The coke oxidizes the ore
to release carbon dioxide and carbon monoxide. The molten iron is used in
BOPF or open hearth steelmaking furnaces or it is poured into molds called
9-7
-------
pigs to form castings and stored for later use. In 1977, 62.0 million
tonnes of pig iron were produced of which only 4.1 million tonnes, 6.5
percent, were shipped between plants. The value of those shipments was
$650.0 million.
Steel, like pig iron, is an alloy of iron and carbon. Pig iron has a
higher carbon content than steel and a greater incidence of impurities,
such as phosphorous, manganese, and silicon. Steelmaking is the process of
oxidizing carbon and impurities in iron and removing them in slag. Three
processes, named for the type of furnace involved in each, are in use
today; the open hearth process, the basic oxygen process, and the electric
arc process.
The open hearth process was developed during the 1870's, and has since
undergone many modifications to adapt the process to changing technological
and economic conditions. An oxygen lance was added after the development
of an economical means of producing pure oxygen. The scrap to pig iron
ratio can be varied from 35 to 65 percent of the charge, depending upon the
availability of steel scrap, and either molten or solid pig iron can be
used. Serious air pollution problems have not been solved, however, and
the real price of its fuels has increased 300 percent since 1973. These
problems, and high labor and capital costs, contributed to the decline of
open hearth process during the 1970's.
Most of the open hearth production has been replaced with steel from
basic oxygen furnaces (BOPFs). BOPF facilities require less capital in-
vestment and less labor, and they operate at lower cost. Because air
pollution problems are more easily controlled on a BOPF furnace, and since
the BOPF requires no energy input other than molten pig iron, investment in
BOPF furnaces has been preferred to investment in open hearth facilities
for the last 20 years. Each heat takes 45 minutes to one hour, compared to
a melt time of 8 to 10 hours in the open hearth. However, the BOPF is not
as flexible as the open hearth furnace and requires a limit of 25 to 30 per-
cent on the amount of scrap that can be added.
Two improved furnaces, the Q-BOPF and the KMS system furnace, are
currently being installed. Introducing oxygen from the bottom of the
furnace rather than from a lance suspended over the batch, the Q-BOPF can
be installed in existing open hearth facilities reducing capital costs by
9-8
-------
40 to 50 percent. The Klb'chner Maxhiitte Scrap system incrementally increases
productivity by blowing oxygen simultaneously from above and below the
batch. Both processes are slightly more flexible than the BOPF and are
capable of using more scrap in each heat. They are more efficient and have
longer lives than the BOPF.
The electric arc furnace has greater quality control than the other
methods but has higher operating costs. The major advantage is its ability
to use a scrap charge as high as 100 percent. The remainder of the charge
can be made up of direct reduced iron, eliminating any dependence on blast
furnace and coking operations. This independence reduces the initial
investment for new steel plants and allows greater entry into the steel
industry.
Steel from all furnaces is poured into ingots or cast directly by the
new continuous casting process into semifinished shapes. Raw steel in
ingot form passes on to the semifinishing stage. Solidified ingots are
reheated to a uniform temperature and rolled into blooms, billets, or
slabs. All shapes are rectangular forms with rounded edges. Blooms have
round or rectangular cross sections and are used to produce structural
shapes, rails, and rounds. Billets are smaller and are rolled from blooms.
These shapes are rolled into wire rods, rounds, and bars. Slabs have wide,
thin, cross-sections, are shorter than blooms and billets, and are rolled
into plates, sheets, strip, and skelp.
Continuous casting of the molten steel bypasses the ingot stage.
Semi-finished shapes are drawn from the bottom of a mold in which the steel
is cooling and solidifying. Although only 16.9 percent of all U.S. steel
was continuously cast in 1979, research and development is increasing this
share by broadening the applications of the process. Costs are lowered in
two ways by use of the process. First, the ingot casting stage and the
subsequent reheating are both avoided, reducing capital, labor, and energy
costs. Second, the yield is increased, that is, the tonnage of semi-finished
shapes produced from a given tonnage of molten steel is greater when using
continuous casting.
Semi-finished steel shapes are then rolled, drawn, extruded, and
forged in the finishing processes to produce steel mill products. Certain
steel products are milled into semi-finished shapes and directly into
9-9
-------
finished products such as rails and plates in a continuous operation. Most
semi-finished products are stored for milling at another plant.
Hot rolling of steel between horizontal bars reduces shapes to desired
cross-sectional dimensions. Cold rolling of certain products improves
certain characteristics of the steel. Drawing, or pulling steel through a
die, reduces rods to wire and other similar products. The extrusion process
produces finished steel by forcing steel, which is compressed above its
elastic limit, through an opening to take on the shape of the opening.
Some products are forged by hammering or pressing (mechanically or hydrau-
lically) the metal into the desired shapes.
Further processing yields other finished steel products. For example,
skelp (rolled from slabs) is welded to produce pipe or pierced to produce
seamless tubing. Heat treatments improve strength and hardness. Some
products are coated with other substances such as tin (tinning) or zinc
(galvanizing).
9.1.2.2 Product Description.7 All raw steel production falls into one
of five standardized grades, generally known as carbon steels, alloy steels,
high-strength, low-alloy steels, stainless steels, and tool steels. Independ-
ent trade associations and government agencies have adopted specifications
for tensile strength, hardness, and chemical composition that steels from
all producers must meet in order to be used for certain applications.
Carbon steels contain very small amounts of alloying elements and less than
1.65 percent manganese, 0.6 percent silicon and 0.6 percent copper. Carbon
content falls in the range of 0.08 percent and 1.7 percent. About 90
percent of all finished steel shipments are carbon steel, eventually used
in the production of machines, auto bodies, ship hulls and structural steel
for buildings.
Steels in the second category, alloy steels, contain larger amounts of
manganese, silicon, and copper, as well as percentages of other elements
which give special characteristics to the metal. Greater strength, corro-
sion resistance, and special electrical properties have induced growth in
electrical equipment, industrial machinery and equipment, and the auto and
construction industries. Shipments of alloy steels amounted to about
8 percent of the total.
9-10
-------
The three types of specialty steels are stainless, tool, and high-
strength, low-alloy steels. Stainless steels, used for their strength and
their resistance to temperature change and corrosion, have chromium and
nickel added to impart these special properties. Tool steels have extra
strength and hardness due to the addition of tungsten and molybdenum. They
are used in cutting and shaping parts for power driven machinery and metal-
working machinery. High-strength, low-alloy (HSLA) steels contain small
amounts of the alloying elements but are stronger than carbon grades because
of special processing techniques. Important to applications where strength
and low weight are both critical, their use is increasing in automobiles,
railroad freight cars, and buildings. Table 9-5 shows that the production
of alloy and specialty steels is becoming a larger portion of total raw
steel output due to the special properties they offer.
Steel producers, unable to differentiate their products from the
steels of the same grade and classification from other producers must re-
sort to competition on the basis of price or on some other basis in order
to sell their output. As discussed below in Section 9.1.4, steel companies
compete on the terms of sale, in the provision of technical assistance, and
in faster delivery. Rarely do firms offer discounts from their list prices.8
In 1979, the steel industry reported 140.9 tonnes of raw steel capacity.
Table 9^4 shows that this is a decline of 3 percent from the 1977 high of
145.0 tonnes. Industry analysts indicate that the lost capacity is due to
the closing of old, inefficient plants. Some steel capacity is being
replaced with electric steelmaking furnaces.
Capacity utilization varies with economic activity in the domestic
economy. During recessions, steelmakers reduce their capacity utilization
rather than reduce the price of steel. As conditions improve, utilization
increases.
Yield is the amount of finished steel production from a given level of
raw steel production. Table 9-6 indicates that yield has been increasing
since 1971. Much of the improvement is directly related to the amount of
raw steel being continuously cast into semi-finished shapes. This increase
in yield helps to offset the decrease in capacity. For example, a raw
steel capacity of 145 million tonnes with 71 percent yield produces 103 mil-
lion tonnes of finished steel. A capacity of 140 million tonnes and a
9-11
-------
TABLE 9-5. RAW STEEL PRODUCTION BY TYPE, 1968-19794
Grades'
Year
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
Carbon
105,477
113,246
106,513
97,075
106,774
120,426
114,857
91,045
101,612
98,094
106,064
1,105,438
Alloy
(thousand
12,484
13,482
11,634
11,043
12,681
14,663
15,388
13,763
12,980
13,917
16,475
16,337
Stainless
tonnes)
1,299
1,423
1,160
1,146
1,419
1,714
1,950
1,008
1,528
1,689
1,773
1,991
Total
119,260
128,151
119,307
109,264
120,874
136,803
132,195
105,816
116,120
113,700
124,312
123,687
Percent of
Carbon
88.4
88.4
89.3
88.8
88.3
88.0
86.9
86.0
87.5
86.3
85.3
85.3
Alloy
10.5
10.5
9.7
10.1
10.5
10.7
11.6
13.0
11.2
12.2
13.3
13.2
total
Stainless
1.1
1.1
1.0
1.1
1.2
1.3
1.5
1.0
1.3
1.5
1.4
1.5
9-12
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TABLE 9-6. STEEL PRODUCTION AND YIELD, 1971-19799
co
Year
1971
1972
1973
1974
1975
1976
1977
1978
1979
Raw steel
production
109.3
120.9
136.8
132.2
105.8
116.1
113.7
124.3
123.7
Producer
Shipments inventory change
79.0
83.3
101.1
99.3
72.5
81.1
82.7
88. 8
91.0
(million tonnes)
-3.5
+1.9
-4.0
-3.4
+3.1
+2.7
-1.8
+1.8
-0.9a
Finished
steel production Yield
75.5
85.2
97.1
95.9
75.6
83.8
80.9
90.6
90.9
(percent)
69.1
70.5
71.0
72.5
71.5
72.2
71.2
72.9
73.9
Estimated.
-------
yield of 73 percent produces 102.2 million tonnes, a difference of less
than 1 percent.
Table 9-7 shows that the production and consumption of steel mill
products over the past ten years has followed the level of economic activity
in the U.S. In years of rising real domestic GNP, steel production also
rises. As the economy fell into recessions in 1969 and 1974, steel produc-
tion also declined. Industry analysts explain that this occurs because
orders for steel mill products are tied to the level of capital spending,
which usually falls during recessions.
Many analysts also point out that when steel making capacity is under-
utilized, rather than decreasing production, steel firms of any nationality
will try to export excess production.11 Thus the amount of steel available
for consumption in any one country depends not only on the level of economic
activity in the "home" country, but also on the level of activity in foreign
countries as well. Often this is described as using steel exports to pull
a national economy out of a slump. The data in Table 9-7 suggest that this
is the case. Each time the U.S. entered a recession, exports of steel mill
products increased. Since, as observers note, the economic activity of the
rest of the western world often lags behind that of the U.S., sharply
increased imports can be explained by noting that foreign economies are
entering recessions as the U.S. economy is recovering and foreign producers
sell their excess production on the U.S. market.
As in the case of raw steel, steel mill products also conform to
standards set by trade associations and government agencies. Jn addition,
individual user firms may ask that products meet specifications of their
own design. The effect is to reduce the market power of integrated firms
vis-a-vis one another. Unable to differentiate these products from others
in the same standardized class, steel producers are forced to compete in
the provision of ancillary services, as steel mill product prices suffer
from the same price rigidity as raw steel. However, as discussed in Sec-
tion 9.1.4, the range in which integrated steel makers can compete is much
broader than in raw steel production.
Raw materials requirements for iron and steel production have generally
been decreasing since the 1950's. Over the past 30 years, productivity of
the blast furnace has been improved by combining inputs in different propor-
tions. The coke rate, for example, has fallen by almost half since 1957
9-14
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TABLE 9-7. DOMESTIC PRODUCTION AND CONSUMPTION OF STEEL MILL PRODUCTS
(thousand tonnes)2
10
Year
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
Real
GNP ($109)
1972 dollars10
1,051.8
1,078.8
1,075.3
1,107.5
1,171.1
1,235.0
1,217.8
1,202.1
1,274.7
1,340.5
1,399.1
1,431.6
Net
shipments
steel mill
products
83,330.4
85,163.8
83,370.6
78,959.5
83,284.1
101,087.6
99,311.3
72,535.8
81,114.9
82,687.2
88,845.1
90,956.2
Imports
16,292.9
12,731.7
12,124.1
16,621.4
16,039.9
13,743.6
14,487.7
10,897.5
12,958.6
17,514.7
19,173.0
15,892.2
Exports
1,968.4
4,743.9
6,406.4
2,565.0
2,606.1
3,676.3
5,291.7
2,679.0
2,407.7
1,817.2
2,057.2
2,361.1
Apparent
consumption
97,654.9
93,151.6
88,088.3
93,015.9
96,717.9
111,154.9
108,507.3
80,754.3
91,695.8
98,384.7
105,960.9
104,487.3
Imports
as percent of
consumption
16.7
13.7
13.8
16.9
16.6
12.4
13.4
13.5
14.1
17.8
18.1
15.3
-------
through a variety of adjustments such as sizing the coke, using sintered
and agglomerated ores, increasing blast heat, and adding natural gas, tar,
pitch, and oil as supplementary fuels. The improved productivity results
in increased capacity of existing facilities permitting, as in one case, a
furnace with 1,360 tonne rated capacity to produce as much as 2,725 to
3,175 tonnes of iron.12
The advent of the electric furnace helps to explain rising electricity
and rising scrap requirements per tonne of steel.13 Electric furnaces can
use charges as high as 100 percent scrap, a much larger proportion than
that of the open hearth (35 to 60 percent) or of the BOPF (25 to 30 percent).
Sufficient electric arc capacity was added to reverse the decreasing scrap
rate which occurred during the 1960's as the BOPF replaced the open hearth.
Labor input to the production of steel also is declining as the indus-
try converts from open hearth to BOPF and electric arc production of raw
steel.13 Continuous casting is helping to reduce the labor input into
steel mill products output. Productivity measured in tons per manhour
improved 27 percent from 1956 to 1976. Value added per employee has been
increasing steadily but has slowed its rate of increase in recent years.
Much of the iron ore that is used in the United States comes from the
Mesabi range of Minnesota. About 38 percent is imported. Table 9-8 shows
the increasing proportion of imports in the supply of iron ore. In 1973,
domestic production supplied 66.4 percent of total iron ore. Ninety-seven
percent of the supply came from North and South America. Canada was the
largest foreign source of iron ore, supplying 16 percent of the total U.S.
supply.
In a study prepared by the Federal Trade Commission in 1977, the top 8
steel producers were found to be mostly self-sufficient in 1974 iron ore
supply.16 They held interests in domestic and foreign ventures which
supplied from 59 percent of total 1974 ore requirements (Republic) to the
production of more ore than necessary for proprietary consumption. Alone
among the top 8 steel firms, U.S. Steel produced more ore than it consumed,
selling 32 percent of its 1974 production. Those seven firms which were
not entirely self-sufficient purchased the remainder of their ore require-
ments by contract from independent suppliers.
9-16
-------
The other important input to steel production is iron and steel scrap.
As shown in Table 9-8, the United States has a rich supply of scrap, and is
a significant net exporter.
Scrap has three major classifications, home, prompt industrial, and
obsolete scrap. Home scrap is generated at steel mills and is the unavoid-
able byproduct of reducing raw steel to semi-finished and finished steel
mill products. Consisting of trimmings, scrapings, ends and rejected
materials, it is quickly recycled into making new steel. Thus, the supply
of home scrap is completely dependent on the efficiency of the rolling
mills and the level of production of steel mill products and, in the short
run, is price inelastic. Home scrap makes up about 60 percent of all scrap
consumed.
In the same way, prompt industrial scrap, which arises from the manu-
facture of products from steel, is also price inelastic. Its supply depends
on the levels of production and on the efficiency with which the steel is
used. Since manufacturers already recycle any scrap they produce, an
increase in the price of scrap is unlikely to produce much of an increase
in the amount supplied. Prompt industrial scrap accounts for 15 percent of
all scrap consumed.
The more price elastic portion of scrap supply is obsolete scrap,
which comes from appliances, rails, salvage, and especially, auto bodies.
Ferrous products not already recycled provide a source of raw material,
some of which could be prepared for market as the price of scrap rises.
Steelmakers purchase the remainder of their scrap needs from dealers of
obsolete scrap.
9.1.2.3 Demand. Between 1945 and 1974, apparent steel consumption
grew 4.5 percent per year. During the 1975 recession it decreased by
26 percent. Since then, economic recovery has forced consumption up by
6.6 percent per year, though it has not yet reached 1973-1974 levels.
Demand for steel products has grown slowly relative to the growth of demand
for other products. Reasons include: (1) the decline of steel-intensive
industries such as railroads; (2) smaller requirements of steel due to
increased strength or hardness; (3) comparatively low prices of steel
imports; and (4) the relatively low prices for substitute materials.
9-17
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UD
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M
CD
TABLE 9-8. FOREIGN TRADE IN IRON ORE AND SCRAP
(million tonnes)
Iron ore14
Year
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
Domestic
production
88.3
89.7
91.2
82.1
76.6
89.1
85.8
80.2
80.6
56.5
82.9
86.5
Import
44.7
41.4
45.6
40.7
36.4
44.0
48.8
47.4
45.1
38.5
34.1
35.6
Exports
6.0
5-3
5.6
3.1
2.1
2.7
2.3
2.5
2.9
2.1
4.3
5.2
Apparent
consumption
125.0
125.8'
131.3
119.7
110.9
130.4
132.2
125.1
122.7
92.9
112.8
116.8
Iron and
Shipments3
30.5
33.5
31.0
31.0
37.8
40.6
46.6
37.7
37.6
38.2
41.8
42.7
steel scrap15
Imports
0.3
0.3
0.3
0.3
0.3
0.3
0.2
0.3
0.5
0.6
0.7
0.7
Exports
6.0
8.3
9.4
5.7
6.7
10.2
7.9
8.7
7.4
5.6
8.2
10.0
Does not include home scrap. Consumption in 1979 was 89.8 million tonnes.
-------
Because steel is used to produce final consumption or capital goods,
its demand is derived from the demand for these final goods. Table 9-7
shows the cyclical nature of this derived demand for steel mill products by
relating total shipments with real GNP. In times of quickly rising GNP,
steel demand is strong and shipments are high. Demand falls during reces-
sionary periods as GNP growth declines. This is a result of the cyclical
nature of the consuming industries, automobiles, capital goods, and con-
struction, and their sensitivity to economic conditions.
The greatest percentage of demand comes from the automobile industry,
as shown in Table 9-9. In the past 20 years, shipments to the auto industry
have averaged about 20 percent of total steel mill products. However,
recent trends have threatened to reduce the amount of shipments to that
industry. Imported cars have taken a large share of the domestic market,
reducing demand for domestic cars and indirectly importing steel from other
countries. Improvements in the quality and durability of shipments to
domestic users have decreased the tonnages of steel used per car. Aluminum
and plastics have been substituted for many of the steel portions of cars.
Finally, the trend toward smaller models reduces the amount of steel used
per car.
The construction industry is the second largest user of steel- mill
products. Shipments to this sector amounted to 15 percent of total ship-
ments since 1961. A portion of the steel in construction, however, comes
from steel service centers, a sector which over the same period accounted
for an additional 17 percent of shipments. Because the construction industry
is highly sensitive to business cycles, demand for construction steel fell
during the 1975 recession by almost 32 percent and has not yet regained its
1974 level of 16 million tonnes. Changes in the usage pattern of steel may
also affect this industry. Increased strength to weight ratio will decrease
the tonnage of steel required per unit of construction. In housing and
building construction, the increase in the popularity of mobile and prefab-
ricated homes may increase steel demand, while energy conservation goals
may reduce demand by substituting insulating materials such as concrete and
wood.
Other changes have occurred in the distribution of steel demand.
Steel service centers are growing in importance, offering fast delivery and
9-19
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UD
ro
o
TABLE 9-9. SHIPMENTS OF STEEL MILL PRODUCTS BY SELECTED CLASSIFICATIONS
(thousand tonnes)17
Automotive
Year
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
Tonnes
17,481
16,580
13,131
15,860
16,526
21,062
17,171
13,802
19,369
19,495
19,280
16,893
Percent
21.0
19.5
15.9
20.1
19.8
20.9
17.3
19.0
23.9
23.6
21.7
18.5
Steel
service centers
Tonnes
12,799
14,318
14,538
13,085
15,238
18,491
18,507
11,521
13,256
13,922
15,724
16,552
Percent
15.4
16.8
17.7
16.6
18.3
18.3
18.6
15.9
16.3
16.8
17.7
18.2.
Construction3
Tonnes
12,765
12,791
12,114
12,349
12,378
15,595
15,975
10,928
10,895
10,934
11,877
12,449
Percent
15.6
15.1
14.7
15.6
14.9
15.4
16.1
15.1
13.4
13.2
13.4
13.7
Machinery
Tonnes
8,510
8,475
7,867
7,515
8,330
9,847
9,905
7,621
8,219
8,366
8,966
9,182
Percent
10.2
10.0
9.6
9.5
10.0
9.7
9.8
10.5
10.1
10.1
10.1
10.1
Containers
Tonnes
7,169
6,482
7,053
6,543
6,002
7,086
7,455
5,491
6,272
6,091
5,983
6,143
Percent
8.6
7.6
8.5
8.3
7.2
7.0
7.5
7.6
7.7
7.4
6.7
6.8
Kails
Tonnes
2,765
3,034
2,810
2,725
2,477
2,928
3,100
2,859
2,772
2,937
3,220
3,729
Percent
3.3
3.6
3.5
3.4
2.9
2.9
3.1
3.9
3.1
3.6
3.6
4.1
Other
Tonnes
21,841
23,484
24,858
20,883
32,333
26,069
27,198
20,314
20,362
20,942
23,795
26,008
Percent
26.2
27.6
30.2
26.4
34.7
25.8
27.4
28.0
25.1
25.3
26.8
28.6
Total
Tonnes
83,330
85,164
82,371
78,960
93,284
101,088
99,311
72,536
81,145
82,687
88,845
90,956
Includes construction and contractors' products.
'includes agricultural machinery and electrical equipment.
-------
small lot sizes for customers whose orders do not meet minimum mill require-
ments. The container industry, traditionally a fast growing segment, has
had serious competition from a-luminum cans and plastic bottles. New steels
and improved can making methods developed to compete with the newer materials
may reverse the downward trend and cause a growth in demand. Railroads
recently started renovating many engines, cars, and many miles of track,
and have increased their consumption of steel 50 percent since 1976.
Concrete competes with structural steel in heavy construction.18 At
present steel is used in tall vertical structures and concrete is used in
short horizontal structures, except in the case of bridges with exception-
ally large spans. Improvement of 100 percent in the strength of structural
steel has contributed to the size of buildings supported by steel. But a
600 percent increase in the strength of reinforced concrete has allowed the
use of concrete in taller structures previously built with steel. Small
multi-story buildings can be constructed with concrete at costs 25 to
35 percent lower than with steel.
Another strong substitute for steel is aluminum.18 Although aluminum
production is only 5 percent of the tonnage of steel, since it is a lighter
metal, this amounts to 15 percent by volume. Almost 50 percent of aluminum
production competes directly with steel in traditionally steel markets.
The dominance of the tinplate steel can, 100 percent of the market in 1955,
has been eroded to less than 40 percent through the substitution of aluminum
in containers. Lightweight, formability, and high recycling value are the
reasons for this substitution.
In every market, steel producers must compete with plastics.18 Although
many plastics offer competitive costs per unit strength, plastics are
purchased because of other factors; for example, low-density, ease with
which they can be worked into finished products, and the range of hardness,
flexibility, color, and degree of opacity which can be specified. Most
importantly, however, are the falling prices of plastics with respect to
the price of steel.
9.1.2.4 Foreign Trade. Import penetration of the domestic steel
market has been increasing since 1959. Prior to the 1957 strike, the last
and most lengthy in steel history, the U.S. had been a significant net
exporter of steel; exports were 4.8 million tonnes and imports were 1.1 mil-
lion tonnes in 1957. By 1959 the situation had reversed as domestic steel
9-21
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users imported 4.0 million tonnes to meet demand that could not be satisfied
by the domestic producers. Exports that year were only 1.5 million tonnes.
Users continued to import steel through the 1960's as a hedge against
uncertain domestic supplies.
Table 9-10, showing world production of raw steel, illustrates the
declining importance of the U.S. share of production. Between 1956 and
1978, world raw steel production increased 151 percent. Japan's growth of
output led the rest of the world by increasing 750 percent. In comparison,
U.S. output increased only 18.9 percent over the same period. The U.S.
share of world total output thus fell from 36.8 percent in 1956 to 17.5 per-
cent in 1978.
The result of this low growth is that U.S. producers failed to gain a
portion of the expanding world market for steel. Exports, shown in Table 9-7
have remained essentially constant between 1956 and 1978, while other
countries substantially increased their exports. Over the same period
imports as a percentage of apparent consumption rose from 1.7 percent to
15.2 percent.
Domestic producers explain this decline by claiming that foreign firms
have unfair advantages.20 First, while domestic producers have had to
comply with environmental regulations, foreign firms are free from these
obligations or else the home governments of foreign firms subsidize compli-
ance costs. Second, most foreign steel industries are subsidized because
it is believed that domestic steel industries provide governments with
secure supplies of a basic material. The United States Federal Government,
steelmakers claim, does not provide similar support that would allow the
U.S. steel industry to be more modern and, thus, competitive.12
While there is evidence supporting these arguments, they do not fully
account for the decline of the competitiveness of the U.S. steel industry.
Foreign firms, to compete in the export market, take advantage of economies
of scale, geographic situations, and advanced, cost-reducing technologies.
For example, Japan has many steel mills of 10 million tonnes of raw steel
capacity and 16 plants located beside deepwater ocean ports.21 The large
size helps the plants realize savings in average costs, while the location
on deep water ports eliminates overland transport charges for steel exports
as well as for raw material imports. Also, every foreign steel industry
9-22
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TABLE 9-10.
RAW STEEL PRODUCTION: UNITED STATES
SELECTED LARGE PRODUCERS
(million tonnes)19
AND
Year
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
United States
119.3
128.2
119. -3
109.2
120.8
136.8
132.1
105.8
116.1
113.1
124.3
123.6
EECa
125.3
134.7
137.5
128.2
126.2
150.1
155.5
125.3
134.3
125.3
133.1
139.7
Japan
66.8
82.1
93.3
88.5
96.9
108.2
117.1
102.3
107.4
102.4
102.1
111.7
Total world
528.3
573.2
593.4
580.4
629.9
697.1
710.0
645.8
683.1
673.9
711.7
747.9
U.S. share of
total world
production
(percent)
22.6
22.4
20.1
18.8
19.2
19.6
18.6
16.4
17.0
16.7
17.5
16.5
European Economic Community.
9-23
-------
produces a larger share of production by the cost advantageous basic oxygen
process and continuously casts a larger portion of its raw steel output
than the U.S. steel industry.8
9.1.3 Structure
The largest 10 to 12 firms account for most of the industry's output.
The high concentration of production within these firms is dependent upon
the forward and backward integration of the firms into all phases of steel
production, fabrication, and raw materials processing. However, the struc-
ture has been changing over time as technological advances are reducing the
barriers to entry into steel production.
9.1.3.1 Concentration. Concentration in the steel industry has been
almost constant since the end of World War II.22 The top 20 firms have
historically contributed 88 percent of the industry's total shipments.
Contributions by the top 10 producers also have been around 78 to 80 percent
of total shipments. The industry's top 4 firms, however, have steadily
lost market share to other firms in the top 10, from almost two thirds at
the end of World War II to just over 50 percent in 1977.
Not only have domestic producers gained market share from the top four
producers but foreign firms have increased their share of total shipments
primarily at the expense of the market shares of the top four. In 1955,
imports represented less than 2 percent of total U.S. supply. By 1978,
that percentage had grown to 18 percent. One study suggests that most, if
not all, of this gain came at the expense of the largest domestic producers.23
Geographic concentration of production is also very high.22 Six
Middle Atlantic and North Central states account for 75 percent of all
production. Proximity to raw materials is, historically, the most important
determinant of location. Four-fifths of all iron are consumed in blast
furnaces is mined and transported within the Great Lakes Region. Between
55 and 60 percent of all coking coal is mined in Pennsylvania, Indiana, and
Ohio. The high costs of transporting low value bulk raw materials led to
the situation of facilities near waterways and rail centers. The growth of
electric furnace operations, however, has allowed steelmakers greater
flexibility in the location of steel production.
9.1.3.2 Integration and Diversification. Vertical integration is
common in the steel industry. A firm classified as fully integrated would
9-24
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produce coke, pig iron, raw steel, semi-finished steel, and finished steel.
Seventeen of the top 20 steel companies operating 57 plants are fully
integrated.24 A semi-integrated steel firm purchases pig iron and scrap to
produce ingots and semi-finished and finished products. Mini-mills, many
of them in alloy steel production, are examples of semi-integrated mills.
Thirty-three firms operating 47 mills are semi-integrated. The 43 noninte-
grated firms purchase raw steel and semi-finished shapes for fabrication
into finished products at 57 plants. Nonintegrated firms include those few
merchant blast furnaces which produce pig iron for sale only.
Although most of the 20 largest firms are integrated from blast fur-
nace to finishing, some of the larger firms extend backward and forward
even further. As of 1977, 52 percent of the coal, 92 percent of the coke,
and 97.4 percent of pig iron used in steel production was produced captively.
Integration gives firms precise control over the supply, grade, and chemical
composition of its raw materials.
Since the early 1960's, diversification trends have led conglomerates
to acquire steel firms and have led steel producers to invest in nonsteel
operations.25 Despite profitability problems and obsolete equipment with
large overhead costs, the large investment in fixed assets provided deprecia-
tion allowances and resulted in large cash flows. This made steel firms
attractive to conglomerates and many firms have been acquired for these
reasons since 1960.
Steel firms used their cash flows to diversify out of unprofitable
steel making operations.25 Some producers acquired firms in such different
areas as insurance, chemicals, and home building. AISI reports that only
40 percent of the income of the 5 largest steel firms derives from steel
operations and 60 percent derives from diversified interests. Seventy
percent of their assets, however, are tied to steel production, while only
30 percent are tied to nonsteel operations. Other firms have a greater
percentage of their assets devoted to steel making.
9.1.3.3 Costs and Economies of Scale. Vertical integration also
reduces costs through energy savings. Fully integrated firms are equipped
with coke ovens, blast furnaces, steel furnaces, and rolling and finishing
mills. Pig iron and steel are kept at high temperatures to eliminate the
need for reheating. Integration, then, is a necessity for the use of a
9-25
-------
BOPF, which uses the latent heat of molten pig iron to start the chemical
reactions of steelmaking. Waste heat and oven byproducts can be used as
fuels in other stages of production.
Capacity decisions by steel firms are heavily influenced by the econo-
mies of scale offered by certain equipment, e.g., a BOPF or blast furnace,
in performing a step of the production process.26 For example, in compari-
sons between two plants of the same firm, the plant using larger and more
modern blast furnaces, with attendant larger and more modern steel furnaces,
achieved 10 to 15 percent cost advantages over the other plant. Scale
economies at the firm level also appear to be based on the economies of
scale of new equipment. In mergers between steel companies, one of the
reasons often cited for the desirability of the merger was that the increased
demand would support the construction of larger and more efficient units.
Evidence suggests that consolidation of departments of two or more firms
would lead to a cost advantage of 2 to 5 percent.
An important element in scale economies is the effect of technology
improvement.27 As the size of the unit of equipment increases, costs
decrease not only as a result of lower average costs but also as a result
of using another, less expensive technology. In the case of a blast furnace,
larger blast furnaces perform more efficiently because of different chemical
and metallurgical reactions. The size of the blast furnace is reflected in
the input demands and realizes economies of scale in input supply. An
example of this is sintered and agglomerated iron ore, increasing the
percentage of iron in each heat. The combined effects of lower average
costs and more efficient technology together realize the 15 percent cost
advantage of larger equipment.
For U.S. steelmakers, these points are significant. Today's domestic
industry relies on technology based on a smaller scale relative to the
technology of foreign producers. Thus, domestic producers can realize cost
advantages over their foreign competitors by expanding into large scale
production.
9.1.3.4 Barriers to Entry. The largest barrier to entry is the
initial capital investment; as seen above, an efficient new producer would
have to capture 2.5 to 5 percent of the total shipments. This requires
large steelmaking furnaces and rolling mills. In addition, using BOPF or
Q-BOPF furnaces requires investment in blast furnaces and coke ovens.
9-26
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Access to raw materials is a major concern to an industry entrant.
Most iron ore reserves are captively owned or produce ore under contract to
a major firm. No estimate can-be made of the probability that a new firm
will not be able to purchase iron ore, but the success of the Japanese
industry suggests that the probability is high that firms can acquire iron
ore. As noted above, the United States has a plentiful supply of scrap so
that access to scrap requirements will not pose any barrier. Metallurgical
(coking) coal has a limited supply, much of which is owned by or under
contract to existing steel firms.
Recent technological advances have reduced some of these barriers.
Though mini-mills typically have output amounting to less than 1 percent of
the industry's shipments, many firms have entered the industry with these
plants. Mini-mills reduce the capital barrier by not depending on blast
furnaces or coke ovens. Raw materials are scrap and electricity, both of
which can be obtained easily in steel consuming regions of the country.
Hence, geographic restrictions based on ties to iron ore and coal are
broken.
9.1.4 Conduct
9.1.4.1 Pricing. Steel firms maintain list prices on standardized
products.28 For nonstandard products, such as nonstandard size, shape,
chemical composition, and other characteristics customers pay "extras."
Since prices are quoted f.o.b. at the mill, the customer pays freight
charges. Generally, price competition does not involve posting lower list
prices. In times of slack demand, mills can absorb some or all of the
freight charges, or ignore "extras." Adjusting the terms of sale, e.g.,
repayment schedules, effectively lowers the price of steel.
9.1.4.2 Nonprice Competition. Steel firms practice nonprice competi-
tion.4 This usually takes the form of providing special services ancillary
to the use of steel products. U.S. Steel and National Steel, for instance,
both operate development centers for improving the use of steel in the
manufacture of cans. Technical assistance can be provided in the same
manner for any steel customer.
Because there are many types of steel mill products, firms compete by
specializing in certain products. U.S. Steel, it has been noted, is special
ized in the production of heavy steel products. Similarly, National Steel
9-27
-------
is investing in sheet mill products, capitalizing on continuous casting and
the growth in demand for strong, lightweight sheet steel. Mini mills
produce many nonspecialized products, most notably concrete support bars.
9.1.5 Performance
9.1.5.1 Financial Performance. The performance of the steel industry
has been erratic in the past ten years. Over this period, the return on
stockholders' equity, a higher value of which makes acquisition of capital
easier, has averaged 7.2 percent. This is 54 percent of the average for
all manufacturing. In only one year, 1974, did the return on steel stock-
holders' equity exceed the average for all manufacturing industries.
In order to develop a more productive and competitive industry, capital
has to be acquired to fund the investments. At this time, the industry's
low level of profitability limits its access to the capital that it needs
to modernize. One constraint is the debt-equity ratio, which increased
from 14 percent in 1950 to 42 percent in 1978. With this historically high
percentage of debt, steelmakers face a reluctant capital market to borrow
in. Second, the low profits and increased debt burden have restricted the
industry's ability to issue new stock. Table 9-11 presents significant
profitability data for the past 11 years.
9.1.5.2 Trends. A significant shift to note in the demand for steel
products is the need for decreased weight. Steel firms are supplying steel
which provide greater strength for less weight, reducing the tonnage of
steel shipped. As the demand for strong, lightweight materials continues,
the growth rate of steel shipments will likely decrease. Another factor
that potentially can reduce the level of steel demand is the declining
consumption of steel per capita in industrialized countries. Substitutes
for steel are being used, particularly aluminum, plastics, and glass. The
trend can eventually be reversed, as per capita steel consumption in non-
industrialized countries has been rising. However, demand for steel in-
creases with the level of capital spending. Thus, the Commerce Department
has projected an increase in steel shipments of 2.2 to 2.5 percent per year
through 1983.30 Other projections have been in this range through 1984.31
Thus, the growth of demand will slow but will not decline because of the
normally growing market.
9-28
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tv>
ID
TABLE 9-11. SELECTED FINANCIAL INDICATORS OF THE U.S. IRON AND STEEL INDUSTRY
(current dollars in millions)29
Year
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
Total
revenues
18,679.6
19,231.0
19,269.5
20,357.8
22,555.7
28,863.2
38,243.6
33,676.3
36,462.4
39,787.4
46,877.3
Net
income
992.2
879.4
531.6
562.8
774.8
1,272.2
2,475.2
1,594.9
1,337.4
23. 2b
1,291.9
Net income -r
revenues
5.3
4.6
2.8
2.8
3.4
4.4
6.5
4.7
3.7
0.06
2.8
Stock
holders
equity
12,617.5
12,836.0
12,966.0
13,281.4
13,674.5
14,513.5
16,243.2
17,192.2
18,027.3
17,603.7
18,403.3
Net
income T
stock
holders
equity
8.2
7.0
4.1
4.1
5.8
9.3
17.1
9.8
7.8
0.1
7.3
Working
capital
ratio
2.0
1.8
1.9
1.9
1.9
1.9
1.8
2.0
1.9
1.8
1.7
Long
term
debt
4,601.4
4,608.2
5,133.9
5,144.4
5,229.6
4,962.9
4,651.2
5,705.3
6,966.5
7,930.7
7,738.9
Capital
expenditures
2,307.3
2,046.6
1,736.2
1,425.0
1,174.3
1,399.9
2,114.7
3,179.4
3,252.9
2,857.6
2,538.3
As of January 1 each year.
^Reflects impact of closings of Bethlehem Steel plants.
-------
On the supply side, Temple, Barker, and Sloane, Inc., has forecast an
increase in continuous casting capacity to fulfill the need for extra
finished steel.32 The projected increase of 14 million tonnes of capacity
is estimated to produce a greater yield from raw steel production. Thus,
total raw steel capacity is expected to decline by 9.1 million tonnnes by
1986. Most of this reduction in raw steel capacity will be due to the
retirement of obsolete open hearth facilities. A small addition of BOPF
capacity amounting to 2.7 million tonnes, or 3.3 percent, will replace some
of the open hearth plants. A small loss of electric arc capacity is also
forecast.
These forecasts indicate that the structure of the steel industry'will
not change appreciably in the next 5 years, as BOPF production requires
extensive integration and large facilities. Mini-mi 11 entries are not
ruled out; however, they would replace retired electric arc capacity.
9-30
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9.2 ECONOMIC IMPACTS OF REGULATORY ALTERNATIVES
This section presents the estimated impacts of the regulatory alterna-
tives for basic oxygen process furnace (BOPF) shops. As described in Chap-
ter 6, eight types of model plants are used to represent typical new and
modified facilities that might be constructed by the industry in the future.
For shops using 300 ton vessels, two model plants represent greenfield
facilities, two are additions to existing facilities, one is the conversion
of an open hearth shop to a Q-BOPF shop, and one is a modification of an
existing BOPF shop to the KMS process. For shops using 150 ton vessels,
one model plant represents a greenfield facility and one is an addition to
an existing facility.
The impacts of two regulatory alternatives are analyzed. Regulatory
Alternative I is the "do nothing" option, in which case the appropriate
state and local regulations apply. This alternative is used as the baseline
in calculating the economic impacts. Alternative II involves setting roof
monitor emission opacity limits which could be achieved by using local
hooding systems. A third alternative, which would have allowed no roof
monitor emissions by using a total building evacuation system, was not cost
effective as discussed in Chapter 8. Thus, this alternative is not con-
sidered further in this analysis.
Section 9.2.1 summarizes the results of the economic impact analysis.
Section 9.2.2 describes the methodology used to estimate the impacts. The
impact estimates, as well as some qualifying remarks, are presented in Sec-
tion 9.2.3.
9.2.1. Summary
Alternative II has a larger impact on greenfield and modified facili-
ties than on those model plants that represent additions to existing faci-
\
lities. Assuming that producers could pass all additional control costs on
to consumers, the price of finished steel would rise by 0.7 to 1.1 percent
if the BOPF shop were a greenfield or modified facility; the price increase
would be about 0.3 to 0.4 percent on steel produced in an addition to
existing facilities. The impacts are greater for the smaller (150 ton
vessel) shops than for comparable larger (300 ton vessel) shops.
9-31
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If producers absorb all additional control costs, the rate of return
on the integrated steel mill would range from 4.9 to 5.5 percent compared
to its baseline level of 6.2 percent, except for the modified facility.
It is estimated that the model plant representing the modification would
not generate sufficient revenues to cover its operating costs, and would
therefore not be built. For all plants except the modified facility, the
incremental capital requirements range from 13 to 23 percent of the base-
line capital outlay. Modifying an existing facility would require $25
million in additional capital to comply with Alternative II; this represents
an increase of 155 percent over the baseline capital investment of $16
million.
9.2.2 Methodology
The methodology used to estimate the impacts of the regulatory alter-
natives is described in this section. A discounted cash flow (DCF) approach
is used to evaluate the profitability of investing in new production faci-
lities and, more specifically, to determine which one of several alterna-
tive facilities is the most profitable for the firm. For a given type of
production facility, the firm can choose one of two configurations. These
configurations correspond to the regulatory alternatives for which cost
data were provided in Chapter 8. Using the DCF approach, the most profit-
able configuration for each type of production facility can be selected.
The resulting choices show which facilities would be constructed by the
industry in the absence of the regulatory alternatives and thus constitute
a baseline from which the impacts of those alternatives can be measured..
The remainder of this section is organized as follows. A general de-
scription of the DCF approach is provided in section 9.2.2.1. This back-
ground is needed in order to understand the particular application of the
DCF approach that is used to estimate the economic impacts and which is
presented in section 9.2.2.2. Finally; how the impacts are calculated
using this method is discussed in section 9.2.2.3.
9.2.2.1 Discounted Cash Flow Approach. An investment project gener-
ates cash outflows and inflows. Cash outflows include the initial invest-
ment, operating expenses, and interest paid on borrowed funds. Cash inflows
are the revenues from the sales of the output produced by the project, de-
preciation of the capital equipment, and recovery of the working capital at
the end of the project's life. Cash outflows and inflows can occur at any
9-32
-------
If producers absorb all additional control costs, the rate of return
on the integrated steel mill would range from 4.9 to 5.5 percent compared
to its baseline level of 6.2 percent, except for the modified facility.
It is estimated that the model plant representing the modification would
not generate sufficient revenues to cover its operating costs, and would
therefore not be built. For all plants except the modified facility, the
incremental capital requirements range from 13 to 23 percent of the base-
line capital outlay. Modifying an existing facility would require $25
million in additional capital to comply with Alternative II; this represents
an increase of 155 percent over the baseline capital investment of $16
million.
9.2.2 Methodology
The methodology used to estimate the impacts of the regulatory alter-
natives is described in this section, A discounted cash flow (DCF) approach
is used to evaluate the profitability of investing in new production faci-
lities and, more specifically, to determine which one of several alterna-
tive facilities is the most profitable for.the firm. For a given type of
production facility, the firm can choose one of two configurations. These
configurations correspond to the regulatory alternatives for which cost
data were provided in Chapter 8. Using the DCF approach, the most profit-
able configuration for each type of production facility can be selected.
The resulting choices show which facilities would be constructed by the
industry in the absence of the regulatory alternatives and thus constitute
a baseline from which the impacts of those alternatives can be measured.
The remainder of this section is organized as follows. A general de-
scription of the DCF approach is provided in section 9.2.2.1. This back-
ground is needed in order to understand the particular application of the
DCF approach that is used to estimate the economic impacts and which is
presented in section 9.2.2.2. Finally, how the impacts are calculated
using this method is discussed in section 9.2.2.3.
9.2.2.1 Discounted Cash Flow Approach. An investment project gener-
ates cash outflows and inflows. Cash outflows include the initial invest-
ment, operating expenses, and interest paid on borrowed funds. Cash inflows
are the revenues from the sales of the output produced by the project, de-
preciation of the capital equipment, and recovery of the working capital at
the end of the project's life. Cash outflows and inflows can occur at any
9-33
-------
time during the project's lifetime. For this analysis, it is assumed that
all flows take place instantaneously at the end of each year. Furthermore,
it is assumed that all investments are conventional investments, that is,
they are represented by one cash outflow followed by one or more cash irr
33
flows. This assumption insures the existence of a unique internal rate
34
of return for each project. For a project with a lifetime of N years,
there are N + 1 points in time at which cash flows occur: at the end of
year zero, the end of year one, and so on until the end of the Nth year.
The initial (and only) investment is assumed to be made at the end of
year zero. This cash outflow comprises the sum of the fixed capital cost
and the working capital. It is offset by an investment tax credit, which
is calculated as a percentage of the fixed capital cost and represents a
direct tax saving. The cash flow in year zero can be given by the follow-
ing equation:
YQ = (FCC + WC)- (TCRED x FCC) (9-1)
The variables for this and subsequent equations are defined in Table 9-12.
The project generates its first revenues (and incurs further costs) at
the end of year one. The net cash flows in this and succeeding years can
be represented by the following equation:
Yt = (Rt-Et) (1- T) + DtT t = 1, ..., N (9-2)
The first term of equation (9-2) represents the after-tax inflows of the
project generated by sales of the output after netting out all deductible
expenses. Revenues are given by
Rt = P • Q • U (9-3)
Deductible operating expenses, E., are the sum of the fixed and variable
operating costs and can be represented by
Et = V-U + F (9-4)
Variable costs include expenditures on raw materials, labor (operating, su-
pervisory, and maintenance), and utilities. Fixed operating costs include
expenditures for facility use, insurance, administrative overhead, etc.
For income tax purposes, E. is deductible from gross revenues, R.. Hence,
the after-tax cash inflow to the firm can be determined by netting out
these expenses and multiplying the result by (1 - T).
Federal income tax laws also allow a deduction for depreciation of the
capital equipment (not including working capital). Although depreciation
is not an actual cash flow, it does reduce income tax payments (which are
9-34
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TABLE 9-12. DEFINITIONS
Symbol
Explanation
D. depreciation in year t
-t
DF. discount factor = (1+r)
DF sum of the discount factors over the life of the project =
N
I (l+r)"*
t=0
DSL present value of the tax savings due to straight line depreciation
N
t=0
E. operating expenses in year t
F annual fixed costs
FCC fixed capital costs
N project lifetime in years
NPV net present value
P price per unit of output
Q annual plant capacity
R. revenues in year t
r discount rate, or cost of capital
T corporate tax rate
TCC total capital cost
TCRED investment tax credit
U capacity utilization rate
V annual variable operating costs
WC working capital
X minimum.[$2000, .2 x FCC]
Y. net cash flow in year t
9-35
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cash outflows) since taxes are based on net income after deducting the de-
35
preciation allowances. The expression in equation 9-2, D.T, represents
the annual tax savings to the firm resulting from depreciation; it is treated
as a cash inflow. In the analysis in this section, the straight line
method of depreciation is used. (No provision is made for the rapid write-off
of investments in pollution control equipment.) The salvage value of the
facility is assumed to be zero, so the annual depreciation expense is simply
given by (FCC-X)/N, where N is the lifetime of the project and X is an al-
lowance for additional depreciation in the first year of the project's life.
The net cash flows represented by equation 9-2 occur at the end of the
first through the Nth years. The additional cash inflows occur at the end
of the first and Nth year. The additional cash inflow at the end of the
first year is the tax savings attributable to the additional first year
depreciation deduction of 20 percent of the fixed capital cost or $2000,
whichever is less. By law, the basis for calculating normal depreciation
allowances must be reduced by the amount of the additional first year de-
36
preciation. The additional cash inflow at the end of the Nth year occurs
when the working capital, initially treated as a cash outflow, is recovered.
Because these cash flows occur over a future period of time, they must
be discounted by an appropriate interest rate to reflect the fact that a
sum of money received at some future date is worth less than an equal sum
received today. This discount factor, DF., can be given by:
DFt = (1 + r)"* t = 0, 1, ..., N (9-5)
The sum of the discounted cash flows from a project is called the net pre-
sent value of that project. That is,
N
I
t=l
NPV = z (Y. • DF.)-Y or (9-6)
\f CO
N -t
NPV = Z [Y. (1 + r) l] - Y
t=l r °
The decision criterion, if funds are available, is to invest in the project
if it has a positive NPV at a discount rate equal to the weighted average
cost of capital.
9.2.2.2 Project Ranking Criterion. The specific application of DCF
used in the economic analysis is discussed in this section. What is needed
9-36
-------
is a criterion for ranking alternative investment projects in terms of pro-
fitability. It is assumed that, in the absence of the regulatory alterna-
tives, any firm building a new production facility would invest in the most
profitable configuration of that facility. This choice can be compared
with the one that would have to be built to comply with the regulatory
alternative; this forms the basis for calculating price and rate of return
impacts.
Equation 9-6 can be rearranged and used as the ranking criterion. The
procedure begins by substituting the expressions for R and E (given by
equations 9-3 and 9-4, respectively) in equation 9-2. Next, the expressions
for Y in equation 9-1 and Y. in equation 9-2 are substituted into equation
0 \f
9-6. NPV in equation 9-6 is then set equal to zero and the unit price, P,
is solved for by rearranging the terms in Y. so that the price is on the
left hand side of the equal sign and all other terms are on the right hand
side:
P Z V-U + F
r ^^^^^^^^^^^"^^^^^^^^^^^^™
DF-(1-T)-Q-U Q-U (9-7)
where Z = YQ - DSL - WC(l+r)N -Xd+r)1-!
and all other variables are defined in Table 9-12. The resulting expression
for P, called the present worth-cost, has two terms. The first, or
"capital cost", term is that part of the present worth-cost accounted for
by the initial capital outlay (adjusted for the tax savings attributable to
depreciation, recovery of working capital, etc.) and including the return on
the invested capital. The second, or "operating cost", term is a function of
the fixed and variable operating costs. Hence, for any configuration, the
present worth-cost just covers the unit operating costs and yields a rate of
return, r, over the project's lifetime on the unrecovered balances of the
initial investment.
For each type of facility, equation 9-7 is used to calculate the pre-
sent worth-cost of producing a tonne of steel in each configuration. The re-
sults are then ranked in order of cost, from lowest to highest. The most
profitable configuration for a given facility is the one that can produce
the molten steel for the lowest cost.
9.2.2.3 Determining the Impacts of the Regulatory Alternatives. This
section describes how the impacts of the regulatory alternatives are esti-
9-37
-------
mated using the ranking method discussed in section 9.2.2.2. The estimated
impacts are presented in section 9.2.3. Three categories of impacts are
estimated: price, return on investment, and incremental capital require-
ments.
Price impacts are calculated directly from equation 9-7. Given the
present worth-cost of each configuration, cost increases from the base unit
cost of the most profitable facility can be calculated. These cost in-
creases are translated into price impacts by dividing them by the price of
a ton of finished steel.
Whereas price impacts are calculated by assuming that all of the incre-
mental costs associated with a given regulatory alternative are passed for-
ward to the consumer, return on investment (ROI) impacts are estimated by
assuming that the producer absorbs all of the incremental costs, thus lower-
ing the ROI. In this case, the price facing the consumer would not change.
For any regulatory alternative, there may exist a discount rate that would
enable the producer to maintain the imputed cost of the steel at its base-
line level. The baseline cost is the present worth-cost associated with the
most profitable configuration and is determined from the procedure described
in section 9.2.2.2.
The baseline present worth-cost was calculated from equation 9-7 using
a specific value of the discount rate, r. As mentioned previously, the
discount rate employed was the real weighted average cost of capital. The
calculation of the rate of return impact would begin by setting P = P in
equation 9-7, where P is the baseline (lowest) cost and then iteratively
solving for the value of r that equates the right hand side of equation
9-7 with P. This value, say r*, will always be less than r, the baseline
rate of return. The difference between r* for each regulatory alternative
and r constitutes the rate of return impact.
The incremental capital requirements are calculated from the cost data
presented in Chapter 8. The additional capital required to meet the stan-
dards is used as a partial measure of the financial difficulty firms might
face in attempting to conform to the standard.
9.2.3 Economic Impacts of the Regulatory Alternatives
This section presents the estimated impacts of the regulatory
alternatives. Using the methodology described in Section 9.2.2, three types
of impacts are calculated: product price and output, return on investment
(ROI), and incremental capital requirements.
9-38
-------
Table 9-13 shows the capital and operating costs for the eight model
plants under the two regulatory alternatives. These costs summarize the
data presented in Chapter 8 and are provided here to show the form in which
they were used in the economic analysis. The capital costs do not include
an estimate for working capital. The operating costs do not include a
capital recovery charge, that is, they are not annualized operating costs.
Also, the operating costs do not include the cost of the hot metal from the
blast furnace. Using these costs and equation 9-7, the present worth-cost
of a ton of steel produced by each type of facility under each regulatory
alternative was computed and is shown in Table 9-14.
A real after-tax cost of capital of 6.2 percent was used in this anal-
37
ysis. A real rate was used because of the difficulties involved in
estimating actual cash flows, including the effects of inflation, over the
15-year lifetime of the project. Thus, real costs in 1980 dollars were as-
sumed to remain constant over the project's lifetime and a real interest
rate was used to discount these flows. It was also assumed that output re-
mained constant over the lifetime of the project.
All present worth-cost calculations assumed straight-line depreciation
of the capital equipment over 15 years; additional first year depreciation
of $2000; working capital equal to 10 percent of the installed capital
cost; an investment tax credit of 10 percent; and a Federal corporate income
tax rate of 46 percent.
Table 9-14 shows that the present worth-cost of producing a tonne of
steel in a BOPF facility (exclusive of the hot metal cost) ranges from $84
to $112 under Alternative I and from $86 to $116 under Alternative II. The
lower costs occur in those facilities that represent additions to existing
facilities or modifications of 300 ton vessel plants. The highest cost is
found in a 150 ton vessel greenfield facility.
The rest of this section discusses the price and output impacts of the
regulatory alternatives (Section 9.2.3.1), the ROI impacts (Section 9.2.3.2),
and the incremental capital requirements (Section 9.2.3.3).
9.2.3.1 Price and Output Impacts. Table 9-15 presents the most ad-
verse price impacts of the regulatory alternatives for each of the eight
model plants. Facilities would only be affected under Alternative II,
since Alternative I represents regulatory conditions currently facing the
industry. To get an idea of the sensitivity of these impacts to changes in
9-39
-------
TABLE 9-13. SUMMARY COST DATA FOR MODEL PLANTS (1980 dollars)'
Regulatory alternative
I
II
(106$)
Capital Operating Capital Operating
cost cost cost cost
(106$)
(10$/yr)
300 ton vessel plants
Greenfield
187.50 251.83 210.90 257.49
187.50 251.83 214.00 258.26
H (conversion)
117.70 251.83 144.20 258.26
Addition to existing facility
111.90 434.30 130.10 438.67
109.30 432.12 127.50 436.49
Modification (E)
16.00 246.97 40.80 252.89
150 ton vessel plants
Greenfield (F)
97.30 145.60 114.20 149.70
Addition to existing
facility (G)
55.40 243.18 68.30 246.28
aCosts taken from tables in Chapter 8. Alphabetic designations of model
plant types correspond to those used in Chapter 8.
9-40
-------
TABLE 9-14. PRESENT WORTH-COST OF MODEL PLANTS ($/tonne)a
Regulatory alternative
I II
300 ton vessel plants
Greenfield
Ab 97.6 100.9
Cb 97.6 101.4
H (conversion)13 93.6 97.3
Addition to existing facility
Bc 84.6 86.1
DC 84.2 85.5
Modification (E)b 86.0 89.5
150 ton vessel plants
Greenfield (F)d 111.5 116.4
Addition to existing
facility (G)e 96.0 98.0
aCosts were calculated using a discounted cash flow method and assuming the
following:
1) Discount rate =6.2 percent
2) Investment tax credit = 10 percent
3) Straight line depreciation of capital equipment over 15 years
4) Additional first year depreciation of $2000
5) Working capital estimated at 10 percent of the capital cost
6) Corporate tax rate = 46 percent
Output of model plant is 2.90 million tonnes of steel per year.
d
c Output of model plant is 5.35 million tonnes of steel per year.
Output of model plant is 1.45 million tonnes of steel per year.
e Output of model plant is 2.63 million tonnes of steel per year.
9-41
-------
TABLE 9-15. PRICE IMPACTS OF REGULATORY ALTERNATIVE II (%)'
ro
300 ton vessel plants
Greenfield
A
C
H (conversion)
Addition to existing facility
B
D
Modification (E)
150 ton vessel plants
Greenfield (F)
Addition to existing facility (G)
Scenario 1
0.65
0.74
0.71
0.25
0.28
0.67
0.94
0.39
Scenario 2°
0.69
0.78
0.78
0.30
0.28
0.74
1.01
0.41
Scenario 3
0.71
0.83
0.83
0.30
0.30
0.78
1.06
0.44
The analysis uses a 1980 price of finished steel from a BOPF facility of $479 per tonne. Price in-
creases under Alternative II are calculated as the present worth-cost increase over the baseline
(Alternative I) divided by the price of finished steel.
Discount rate of 4.0 percent used in the present worth-cost calculations.
°Discount rate of 6.2 percent used in the present worth-cost calculations (See Table 9-14).
Discount rate of 8.0 percent used in the present worth-cost calculations.
-------
a key parameter, the discount rate, three scenarios were used. In Scenario
1, a real discount rate of 4.0 percent was used in the present worth-cost
calculations; in Scenarios 2 and 3, discount rates of 6.2 and 8.0 percent,
respectively, were used.
The table shows that the price increases become larger as the discount
rate increases, although they are not very sensitive to changes in this
rate. In most cases, doubling the discount rate from 4.0 to 8.0 percent
increases the price impact by onetenth of a percent or less. Under Scenario
1 the price impacts range from 0.3 percent to 0.9 percent. Under Scenarios
2 and 3, the price impacts range from 0.3 to 1.0 percent and 0.3 to 1.1
percent, respectively. The smallest impacts occur for those model plants
representing additions to existing facilities (B,D, and G). Larger impacts
(0.7 to 0.8 percent) occur for the three greenfield facilities using 300
ton vessels (A,C, and H) and for the modified facility (E). The largest
impact of 1.0 percent occurs for the greenfield facility employing 150 ton
vessels (F). The results also illustrate the economies of scale in pollution
control expenditures. The impacts on the two small facilities, F and G,
are larger than those on the comparable large facilities, A and B.
The potential quantity adjustments to these price increases were also
estimated. A horizontal supply curve was assumed. Thus, under Alternative
II, the supply curve would be shifted upwards by an amount equal to the
estimated price increase. Calculating the quantity adjustment resulting
from this shift requires an estimate of the price elasticity of demand for
finished steel, that is, a measure of the responsiveness of the percentage
change in quantity demanded to a percentage change in price. The larger
the value of this (negative) number, the greater the change in quantity
demanded to a given change in price. The product of the demand elasticity
and the percentage increase in price is the percentage decrease in quantity
demanded.
In this analysis, an estimate of -1.37 for the price elasticity of de-
38
mand was multiplied by the largest (1.06 percent) and smallest (0.25 per-
cent) price increases reported in Table 9-15 to obtain a range of percentage
decreases in quantity demanded. These values, -0.34 percent and -1.45 per-
cent, were then multiplied by the projected demand in 1986, 94.0 million
39
tonnes of finished steel, to convert the percentage decreases to absolute
reductions in the quantity demanded. The results show that the reduction
9-43
-------
in the demand for steel produced in BOPF's would range from 0.32 million
tonnes to 1.37 million tonnes in 1986.
9.2.3.2 RQI Impacts. Because the price impacts reflected the effect
of a regulatory alternative applied to one part (the BOPF shop) of an inte-
grated production facility, ROI impacts were determined in a similar manner.
That is, using the price of a tonne of finished steel as a basis for calcula-
ting the price impacts implicitly accounted for all the materials, pro-
cesses, and facilities used in its production: the iron ore, coal, ore
yards, coke ovens, blast furnaces, BOPF shops, molds, etc. Thus, ROI im-
pacts should be reported on the same basis.
The major assumption used to accomplish this is that the BOPF shop
contributes to the return on the entire integrated facility in direct pro-
portion to the ratio of its present worth-cost to the price of finished
steel ($479 per tonne in 1980). Calculations for the eight model plants
showed that this ratio ranged from 18 to 23 percent. The ROI impacts cal-
culated using the method described in Section 9.2.2.3 were weighted by
these ratios; the return on the rest of the integrated facility, 6.2 per-
cent, was weighted by a ratio ranging from 77 to 82 percent, depending on
the model plant. The results are displayed in Table 9-16.
Since Alternative I has no impact, the rate of return for an inte-
grated facility using any of the model BOPF shops is 6.2 percent. Under
Alternative II, the ROI of an integrated facility would range from 4.9 to
5.5 percent; that is, the ROI would fall by 0.7 to 1.3 percentage points
from its baseline level. The revenues from the modified facility would not
cover the operating costs under Alternative II; that is, net revenues were
negative. If a producer could not pass the additional costs on to the con-
sumer, it is probable that the modification would not be made. This is a
"worst case" result. The cost data for the modified facility do not reflect
the economic benefits of the KMS process, such as increased yield and the
ability to use more scrap in the charge. It is possible that these bene-
fits might make the modification economically feasible in spite of the in-
creased control costs.
One final point to consider is whether the additional control costs
would be passed on to the consumer or absorbed by the producer. Some cost
absorption is likely in the short run. However, if firms in the industry
are currently earning a normal return on their investments, then prices
9-44
-------
TABLE 9-16. RATE OF RETURN IMPACTS OF REGULATORY ALTERNATIVES (%)
Rate of return under
regulatory alternative
I II
300 ton vessel plants
Greenfield
A
C
H (conversion)
Addition to existing facility
B
D
Modification (E)
150 ton vessel plants
Greenfield (F)
Addition to existing facility (G)
6.20
6.20
6.20
6.20
6.20
6.20
6.20
6.20
5.45
4.92
4.96
5.37
5.10
a
5.03
4.88
Net revenue is negative; therefore, a real number value of the rate of
return does not exist.
9-45
-------
would rise in the long run by an amount sufficient to cover the additional
control costs. Thus, it appears that the price and output impacts discussed
in Section 9.2.3.1 are more likely to occur than are the rate of return im-
pacts discussed in this section.
9.2.3.3 Incremental Capital Requirements. The additional capital in-
vestment required to comply with Alternative II for each model plant is
shown in Table 9-17. Depending on the type of affected facility, approxi-
mately $13 million to $27 million of additional funds per affected facility
would be required for compliance. Except for the modified facility (E),
this represents an outlay of 13 to 23 percent of the baseline (Alternative
I) capital investment. The additional outlay for the modified facility,
$25 million, is 155 percent of the baseline investment. This large increment
is one reason that a real rate of return, which would equalize the present
worth-cost under Alternative II with that under Alternative I, did not
exist (see Section 9.2.3.2).
9.3 POTENTIAL SOCIOECONOMIC AND INFLATIONARY IMPACTS
Executive Order 12044 requires that the inflationary impacts of major
legislative proposals, regulations, and rules be evaluated. The regulatory
options would be considered a major action (thus requiring the preparation
of Regulatory Impact Analysis) if either of the following criteria apply:
1. Additional annualized costs of compliance, including capital
charges (interest and depreciation), will total $100 million
within any calendar year by the attainment date, if applicable,
or within five years of implementation.
2. Total additional cost of production is more than 5 percent of
the selling price of the product.
The regulatory alternatives for BOPF facilities would not qualify as a
major action by the second criterion, since the largest price increase was
estimated to be 1.1 percent (Table 9-15). The remainder of this section is
devoted to estimating the total additional cost of compliance with Regula-
tory Alternative II.
Projections of additions to BOPF steelmaking capacity from 1981 through
40
1986 were summed to get the total increase in capacity during this period.
For each type of model plant, this sum, 6.8 million tonnes, was translated
into "model plant equivalents" by dividing it by the output of each model
plant. That is, it was assumed that the entire increase in capacity would
9-46
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TABLE 9-17. INCREMENTAL CAPITAL REQUIREMENTS OF REGULATORY ALTERNATIVE IIC
Amount required in excess of
alternative I
Millions
of dollars
Percent
of baseline
300 ton vessel plants
Greenfield
A
C
H (conversion)
Addition to existing facility
B
0
23.4
26.5
26.5
18.2
18.2
12.5
14.1
22.5
16.3
16.7
Modification (E)
150 ton vessel plants
Greenfield (F)
Addition to existing facility (G)
24.8
16.9
12.9
155.0
17.4
23.3
Based on the capital costs in Table 9-13.
9-47
-------
be met by constructing BOPF shops of a particular type, in effect creating
eight scenarios.
The incremental annualize.d costs of compliance were calculated from
the data in Table 9-13. A capital recovery factor, based on an interest
rate of 6.2 percent, a project lifetime of 15 years, and an additional 4
percent charge for general and administrative overhead, taxes, and insurance,
was multiplied by the incremental capital cost for each model plant. This
annualized capital charge was added to the incremental operating costs of
that plant type to get the incremental annualized cost. This figure was
then multiplied by the number of model plant equivalents to obtain the
incremental annualized cost of compliance for the entire industry. The
result is eight estimates of the annualized compliance costs the industry
would incur in 1986 if all projected capacity increases between 1981 and
1986 occurred in that year. Since the capacity increases will not all occur
in any one year, the resulting estimates represent the maximum possible
impacts of this regulatory alternative.
Table 9-18 presents the results of the calculations described above.
The estimates of the incremental annualized costs range from $21 million to
$33 million. Since these estimates are below the $100 million threshold in
the Executive Order, the regulatory alternatives are not a major action and
thus do not require the preparation of a Regulatory Impact Analysis.
9-48
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TABLE 9-18. INCREMENTAL ANNUALIZED COST OF COMPLIANCE WITH ALTERNATIVE II, 1986 (1980 dollars)
300 ton vessel plants
Greenfield
A
C
H (conversion)
ua Addition to existing facility
£ B
D
Modification (E)
150 ton vessel plants
Greenfield (F)
Addition to existing facility (G)
Model plant
equivalents
3
3
3
3
3
3
5
6
Incremental
cost per plant
(io6 $)
9,04
10.25
10.25
7.00
7.00
9.50
6.54
4.96
Annual i zed cost0
(io6 $)
27.12
30.75
30.75
21:00
21.00
28.50
32.70
29.76
Calculated by dividing the total projected increase in capacity between 1981 and 1986, 6.81 mil-
lion tonnes, by the annual output of each model plant and rounding upward to the nearest whole number.
Based on cost data in Table 9-13. Capital recovery factor based on 6.2 percent interest rate and
15 year project lifetime plus 4 percent.
c Product of number of model plant equivalents and the incremental cost per plant.
-------
9.4 REFERENCES
1. 1977 Census of Manufactures. Preliminary Report SIC 3312. U.S.
Department of Commerce. Bureau of the Census. Washington, D.C.,
1977.
2. American Iron and Steel Institute. Annual Statistical Report. Wash-
ington, D.C., various years. 1979.
3. Reference 2, p. 35.
4. Reference 2, p. 55.
5. Merrill, Lynch, Pierce, Fenner, and Smith, Inc. "Institutional Report.
Steel Industry Quarterly Review." February 1980. New York 1980.
p. 18.
6. Frey, Nona Gail. "Queues, Stochastic Demand and the Value of Excess
Capacity in the Steel Industry." Ph.D. dissertation. Texas A and M
University, College Station, Texas. 1976. p. 2-7.
7. Standard and Poor's Corporation. "Industry Survey: Steel-Coal Basic
Analysis." October 11, 1979. New York. p. S-53.
8. Adams, Walter. "The Steel Industry", in Walter Adams, ed. The Struc-
ture of American Industry. MacMillan. New York. 1977. p. 86-129.
9. Reference 5, p. 5.
10. Bureau of Economic Analysis. Business Statistics: 1977. U.S. Depart-
ment of Commerce, Washington, D.C. 1978. p. 4.
11. Federal Trade Commission. Staff Report on the United States Steel
Industry and Its International Rivals: Trends and Factors Determining
International Competitiveness. Washington, D.C. November 1977.
p. 79.
12. Bouman, R. W. "Development of Blast Furnace Fundamentals." Iron and
Steel Management, March 1978. p. 30-31.
13. Reference 11, p. 115-116.
14. Reference 2, and American Iron Ore Association, Iron Ore 1979.
Cleveland, Ohio. 1980.
15. Metal Statistics 1980. p. 209, 210, 212.
16. Reference 11, p. 83-90.
17. Office of Technology Assessment. Technology and Steel Industry Competi-
tiveness. U.S. Congress. June 1980. p. 174.
9-50
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18. Alexander, W. 0. "Competition of Materials." Scientific American.
September 1967. p. 255-266.
19. Reference 17, p. 117.
20. American Iron and Steel Institute. Steel at the Crossroads. Washing-
ton, D.C. January 1980.
21. Mueller, Hans, and Kawahito, Kiyoshi. Steel Industry Economics: A
Comparative Study of Structure, Conduct, Performance. Japan Steel
Information Center. New York. 1978. p. 8.
22. Reference 11, p. 43-56.
23. Reference 5, p. 13-14.
24. Reference 17, p. 187.
25. Reference 11, p. 56-57.
26. Nueno, Pedro. "A Comparative Study of the Capacity Decision Process
in the Steel Industry: The United States and Europe." Ph.D. disserta-
tion. Harvard University, Cambridge. 1973.
27. Reference 26, p. 81.
28. Reference 6, p. 9-10.
29. Reference 17, p. 120.
30. International Trade Administration. U.S. Industrial Outlook. 1979.
U.S. Department of Commerce. Washington, D.C. 1979. p. 174-178.
31. Data Resources, Inc. "Steel Industry Review: Second Quarter 1979."
Lexington, Massachusetts. 1979.
32. Temple, Barker, and Sloane, Inc. "Economic Analysis of Proposed
Effluent Guidelines: Integrated Iron and Steel Industry." Draft
report prepared for Environmental Protection Agency, under EPA Con-
tract Nos. 68-01-4340 and 68-01-4878. Lexington, Massachusetts.
September 1980.
33. Bussey, L. E. The Economic Analysis of Industrial Projects. Englewood
Cliffs, New Jersey. Prentice-Hall, Inc.. 1978. p. 220.
34. Reference 33, p. 222, footnote 13.
35. Reference 33, p. 73.
36. Reference 33, p. 78.
9-51
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37. Economic Impact of NSPS Regulations on Coke Oven Battery Stacks.
Research Triangle Institute. Research Triangle Park, NC. May 1980.
p. 8-45, 8-47.
38. Hekman, John S. "An Analysis of the Changing Location of Iron and
Steel Production in the Twentieth Century." American Economic Review.
67:123-133.
39. Reference 32, Exhibit 1.
40. Reference 32, Exhibit 10.
9-52
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9.2 REFERENCES
1. 1977 Census of Manufactures. Preliminary Report SIC 3312. U.S. Depart-
ment of Commerce. Bureau of the Census. Washington, D.C. 1977.
2. American Iron and Steel Institute. Annual Statistical Report. Washing-
ton, D.C. various years.
3. Frey, Nona Gail. "Queues, Stochastic Demand and the Value of Excess
Capacity in the Steel Industry." Ph.D. dissertation. Texas A and M
University, College Station, Texas. 1976.
4. Standard and Poor's Corporation. "Industry Survey: Steel-coal Basic
Analysis." October 11, 1979. New York, page 5-53.
5. Merrill, Lynch, Pierce, Fenner, and Smith, Inc. "Institutional Report.
Steel Industry Quarterly Review." February 1980. New York 1980. page
5.
6. Bureau of Economic Analysis. Business Statistics: 1977. U.S. Depart-
ment of Commerce, Washington, D.C. 1978.
7. Federal Trade Commission. Staff Report on the United States Steel Inter-
national Rivals: Trends and Factors Determining International Competi-
tiveness. Washington, D.C. November 1977.
8. Bouman, R. W. "Development of Blast Furnace Fundamentals." Iron and
Steel Management, March 1978. pp. 30-31.
9. See reference 2, and American Iron Ore Association, Iron Ore 1979.
Cleveland, Ohio. 1980.
10. Office of Technology Assessment. Technology and Steel Industry Competi-
tiveness. U.S. Congress. June 1980.
11. Alexander, W. 0. "Competition of Materials." Scientific American.
September 1967. pp. 255-266.
12. American Iron and Steel Institute. Steel at the Crossroads. Washington,
D.C. January 1980.
13. Adams, Walter. "The Steel Industry", in Walter Adams, ed. The Struc-
ture of American Industry. MacMillan. New York. 1977. pp. 86-129.
14. International Trade Administration. U.S. Industrial Outlook. 1979.
U.S. Department of Commerce. Washington, D.C. 1979. pp. 174-178.
15. Nueno, Pedro. "A Comparative Study of the Capacity Decision Process in
the Steel Industry: The United States and Europe." Ph.D. dissertation.
Harvard University, Cambridge. 1973.
9-53
-------
16. Temple, Barker, and Sloane, Inc. "Analysis of Economic Effects of Environ-
mental Regulations on the Integrated Iron and Steel Industry." Prepared
for Environmental Protection Agency. NTIS No. PB-273 214. Wellesley
Hills, Massachusetts. July 1977.
17. Hekman, John S. "An Analysis of the Changing Location of Iron and Steel
Production in the Twentieth Century." American Economic Review. 67:123-
133.
18. Data Resources, Inc. "Steel Industry Review: Second Quarter 1979."
Lexington, Massachusetts. 1979.
19. Temple, Barker, and Sloane, Inc. "Economic Analysis of Proposed Effluent
Guidelines: Integrated Iron and Steel Industry." Draft report prepared
for Environmental Protection Agency, under EPA Contract Nos. 68-01-4340
and 68-01-4878. Lexington, Massachusetts. September 1980.
9-54
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APPENDIX A - EVOLUTION OF THE PROPOSED STANDARDS
As required by the Clean Air Act, a review of the Standards of
Performance for New Stationary Sources - Iron and Steel Plants/Basic Oxygen
Furnaces was performed in 1978. This review concluded there should be no
change in the primary emission control level specified in the current NSPS.
A recommendation was made to evaluate fugitive emission control systems
with the intent of incorporating fugitive emissions in the BOPF NSPS at
some future date. Also, a recommendation was made to clarify the period of
time during which sampling should be done for determining compliance with
the primary emission standard.
In November, 1978 Brief Number 78-1534 was filed in the U.S. Court of
Appeals for the District of Columbia Circuit by Group Against Smog and
Pollution, Incorporated, Natural Resources Defense Council, Incorporated,
and Friends of the Earth, Incorporated. The intent of the brief was to
force consideration of an NSPS for BOPF fugitive emission sources. The
U.S. Environmental Protection Agency filed a brief in response on December
15, 1978. After reply briefs by both petitioners and respondent, the
Department of Justice sent a letter dated October 1, 1979 to the Circuit
Court. In this letter USEPA agreed to work towards an NSPS for proposal in
April, 1981.
Subsequent events that have occurred in the development of background
information are presented below in chronological order.
Date Activity
July 6, 1979 Initial project meeting between Emission Standards
and Engineering Division and EPA contractor.
December 2, 1979 Plant visit to Kaiser Steel to observe and discuss
BOPF secondary emission control system.
December 11, 1979 Plant visit to Republic Steel's Cleveland plant to
observe and discuss the BOPF secondary emission
control system.
December 12, 1979 Plant visit to Republic Steel's South Chicago plant
to observe and discuss the Q-BOPF secondary emission
control system.
A-l
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January 25, 1980
February 1, 1980
February 5, 1980
February 26 -
March 3, 1980
March 4, 1980
April 7-11, 1980
April 22, 23, 1980
May 12-16, 1980
May 21, 1980
June 2-6, 1980
June 10-13, 1980
June 23-26, 1980
October 2, 1980
Plant visit to Armco Steel's Ashland, Kentucky plant
to observe and discuss hot metal desulfurization
emission control system.
Plant visit to Inland Steel's East Chicago plant to
observe and discuss the No. 2 BOPF shop secondary
emission control systems.
Don R. Goodwin, Director of Emission Standards and
Engineering Division met with Frances Dubrowski,
attorney for the Natural Resources Defense Council,
for briefing on plans for project for revision of
BOPF standards.
Plant visit to Kaiser Steel to make visible emission
observations on torpedo car desulfurization facility.
A meeting between AISI Environmental Quality
subcommittee, EPA Emission Standards and Engineering
Division, and EPA subcontractor was held to discuss
project status.
Plant visit to Kaiser Steel to make visible emissions
observations on BOPF shop secondary emission sources.
Plant visit to Armco Steel, Ashland plant to make
visible emissions observations on torpedo car
desulfurization facility.
Plant visit to Inland Steel, East Chicago plant
to make visible emissions observations in the No. 2
and No. 4 BOPF shops.
Plant visit to Bethlehem Steel's Bethlehem plant to
observe and discuss BOPF charging and tapping emission
controls.
Plant visit to Republic Steel's South Chicago plant
to make visible emissions observations at their
Q-BOPF.
Plant visit to Republic Steel's Cleveland plant
to make visible emissions observations at their
BOPF secondary emission sources.
Plant visit to Bethlehem Steel's Bethlehem plant to
make visible emission observations at the BOPF
open hood secondary emission control system.
A project review meeting was held between the
Emission Standards and Engineering Division and the
EPA contractor.
A-2
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APPENDIX D
BOPF SHOP FUGITIVE EMISSIONS
MEASUREMENT AND CONTINUOUS MONITORING
D.I EMISSION MEASUREMENT METHODS
There are currently two EPA methods, Method 9 and Method 22,
that are used for measuring visible emissions. In Method 9, a trained
and certified observer visually determines and records the percent
opacity of the emission plume of Interest. In Method 22, an observer
times and records the duration of visible emissions during an
observational period suitably defined for the process of interest.
Method 22 observers are not required to have opacity certification but
are required to have a basic understanding of and experience in the use
of visible emissions testing techniques.
The two methods were used to assess basic oxygen process furnace
(BOPF) fugitive emissions because these emissions do not enter the
atmosphere in a manner that can be practicably quantified by
conventional mass sampling techniques. In addition, fugitive emissions
from processes essentially related to BOPF operations were measured by
Methods 9 and 22. Emphasis was placed on measuring the visible emissions
from the principal BOPF shop roof monitors. Simultaneous visible
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emissions tests were conducted inside the shop at the furnace vessel
to provide more detailed information on fugitive furnace emissions
not captured by the control systems. The additional related steel
processes tested included iron desulfurization, slag skimming and
hot metal transfer. In order to characterize fume exhaust capacities,
duct velocity measurements were made by EPA Method 2 where suitable
testing accessibility was available at the secondary control devices.
All EPA Method 9 testing was done by certified observers throughout
the test series.
The first emission test was conducted at an iron desulfurization
facility from February 26 through March 4, 1980. Initially, only
Method 22 was used. When the first few test runs indicated high
results, one observer was asked to conduct Method 9 observations
simultaneously. (The quantity of uncaptured emissions at this plant
appeared to be directly proportional to the degree of overfilling of
the hot metal cars. Due to the recent heavy rains, the scales used
to weigh the charged torpedo cars were inoperable. Consequently,
many of the cars were filled to overflowing to ensure a full charge
for desulfurization). A total of 18 iron desulfurization tests were
made by Method 22 and 15 tests by Method 9. The presence of high
Method 22 results continued, so a modified Method 22 was used on
the last two tests in which the observers timed only those emissions
that exceeded 15 percent opacity. The results of the modified method
were slightly less than for Method 22. The modified Method 22
results were similar because most of the emissions observed were
significantly higher than 15 percent opacity.
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Visible emissions testing at the BOPF shop at the first plant
was completed April 7-11, 1980. The roof monitor was tested for
19 hours by Method 9 and for 16 hours by Method 22. A total of
21 furnace heats were tested indoors by Method 22 simultaneous
with the roof monitor observations. A typical BOPF heat consists
of several distinct operations. Furnace visible emissions
observations were structured to cover the individial operations to
aid in specific identification of the source of emissions. These
separate operations included: scrap charging, hot metal charging,
blowing, turndown, tapping and deslagging.
Method 22 recommends a maximum observation period of 30 minutes
to prevent observer eye fatigue. A typical BOPF heat lasted about
45 minutes which required constant observation. When it was noted
during the first three heats that the blowing operation produced
no emissions, the observers were asked to stop readings during
blowing except to note any emissions on subsequent heats.
A total of 10 hot metal transfers and two slag skimming
operations were tested by Method 22. The skimming tests were
interrupted because the test personnel were needed to perform
additional testing at the BOP furnace to determine any effect
of high winds which occurred on the last day of testing. A
Santa Anna wind produced velocities up to 60 MPH on April 11.
This high wind did not cause any discernable effect on the level
or duration of furnace or roof monitor emissions. It did cause
significant interference for the outdoor observers testing at ground
level at the hot metal transfer station.
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p
An iron desulfurization station at a second plant was
tested during April 24-26, 1980. Ten desulfurization tests were
conducted by Method 22. The Method 22 emission frequencies
were high so Method 9 was used by one observer for the last
six tests. Exhaust velocity measurements were made using
Method 2 for eight traverses at the baghouse outlet.
The physical configuration of the desulfurization station
at this plant did not permit visible emissions observers to
maintain proper sun angle positioning in the late afternoon. The
observers could not read from the south side of the building
because it was enclosed from ground level to roof. This enclosure
is designed to minimize emission capture interference caused by
the prevailing winds. Whenever the observers were forced to face
toward the sun, they were always standing well within the shadow
of the building which effectively prevented any observational
interferences due to the improper sun angle.
Two BOPF shops at a third steel plant were tested during
May 12-16, 1980. Testing at the Number 2 shop included: 24
hours each of Method 9 and Method 22 observations of the roof
monitor, 19 heats inside at the furnace by Method 22, and
12 velocity traverses by Method 2 at the inlet to the secondary
scrubber control. Indoor emissions for all segments of the heat
cycle were tested for the first three heats. Since no emissions
during normal blowing for the first three heats were observed,
testing of this process segment was discontinued for all
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subsequent heats to be consistent with the procedure established at
the first indoor furnace testing for this industry.
Testing at this plant's Number 4 BOPF shop included the following:
three iron desulfurization tests by Method 22, 12 hot metal transfers
by Method 22, 12 velocity traverses at the secondary baghouse outlet
by Method 2, 6.5 hours of roof monitor testing by Method 9 and 3 hours
of roof monitor testing by Method 22.
The roof monitor over the Number 2 BOPF shop at this plant is open
on only one side. The open side was not visible from the observation
location used for the afternoon readings, consequently, the observers
could not see the origin of any emissions rising over the top edge of
the monitor. In order to document possible interfering emissions from
other sources, two additional observers were assigned to read simul-
taneously from the opposite side of the shop. A comparison of the data
taken simultaneously from both sides of the shop indicated that any
emissions seen from the west location originated from the Number 2 shop.
The extra observers were located facing the sun since they were opposite
the primary observers who carefully positioned themselves with the sun
1n the required 140" arc behind them. Both sets of observers switched
locations at around 2:00 p.m. from morning to afternoon positions. Data
collected by the additional readers at the Number 2 shop cannot be used
for standard setting 1n this industry because an improper sun angle was
used. These data are summarized in Tables 2.2, 2.3, 2.4 and 2.5 of
3
the referenced emissions test report.
Emissions from extraneous sources interfered with visible emissions
observations at this plant. A coke plant adjacent to the Number 2
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BOPF shop produced a periodic steam plume-which occasionally completely
obscured the BOPF shop roof monitor. Emissions from a small lower roof
monitor over the teeming aisle and from the primary scrubber stacks
interfered with testing at the Number 4 BOPF shop. The interferences
at the Number 4 shop were more bothersome than at the Number 2 shop and
much more testing time was lost to these extraneous plumes. The presence
and times of these interferences were noted on the field data forms. The
inherent chronology of Method 9 was used to record observation times lost
to the various interferences. The occurrence of visual interference during
roof monitor testing was addressed by summarizing the data in different
forms to provide a variety of options for data analysis for this plant.
The same type of summaries were used for all subsequent tests at other
plants where significant periods of visual interferences were encountered.
Overall averages were computed using all the roof monitor data for
both Method 9 and 22. Averages were also computed for both methods using
only those data sets without interferences. The Method 9 roof monitor
data were reduced two ways to accommodate the periods of interference.
In the first procedure, sets of 24 consecutive readings were computed as
prescribed by the reference method where periods of interferences were
skipped when counting the sets. The intervals of interference recorded
by the paired Method 9 observers did not always match; therefore, a
direct comparison of the two readers' observations is not assured by
the 24 consecutive reading mode of reduction. In the second procedure,
Method 9 data were divided into successive 6-minute segments that
included the periods of interference. Averages for each 6-minute set
were calculated based on the number of actual readings recorded
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for the set. This second mode of Method 9 reduction provides a
continuing comparison of opacity data between the two observers.
Fugitive emissions testing was performed at a fourth steel plant
during June 2-6, 1980. The BOPF Shop roof monitor was tested for 24
hours by Method 9 and for 23 hours by Method 22. Indoor furnace
emissions were tested for 10 heats by Method 22. Nine velocity traverses
were conducted at the inlet to the secondary collector. Significant
quantities of emissions during the blowing segment of the furnace heat
were observed at this shop; therefore, the entire heat was tested by
Method 22. The problem of observer eye fatigue was addressed by having
the observers read alternate heats only; every other heat was used as a
break period. The only accessible ports for duct velocity traverses at
this shop were directly above the furnaces. Plant safety requirements
prohibited any use of these ports during furnace operations; therefore,
the velocity traverses were made before furnace operations began. There
are three modes, of secondary fume exhaust used at this shop so "cold"
velocity traverses were made in all three modes. A wind shift on the
fourth day of testing made roof monitpr observations from the preferred
locations impossible. The observers moved to an alternate position
which faced the long dimension of the roof monitor and forced the use of
an improper sun angle; therefore, the roof monitor readings from 1:00
to 5:00 p.m. on June 4, should not be included in the data base for this
series.
A testing program for fugitive emissions was conducted at the fifth
steel plant during June 9-16, 1980. Roof monitor observations were
made for a total of 29 hours by Method 9 and 26 hours by Method 22.
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Eleven hot metal transfers were tested by Method 22. A total of 13
furnace heats were observed by Method 22. Rainy weather on the first
day of testing produced marginal conditions for reading the roof monitor.
Periods of interference caused by the weather were noted on the field
data forms. Furnace operation at this plant produced significant
emissions during blowing so that entire heats were read. The observers
tested only on alternate heats to avoid excessive eye fatigue. Lighting
inside the BOPF shop building at this plant was noticeably lower than at
previous shops tested in the series. Light levels measured were below
the 10-foot candle minimum recommended by Method 22 for indoor testing.
This condition probably biased the observations low as the testers
reported difficulty in seeing faint emissions.
The sixth and last plant in the BOPF series was tested during
June 23-27, 1980. The roof monitor was observed for 24 hours by both
Methods 9 and 22. The BOP furnace was tested for 20 heats by Method 22.
Emissions observed during blowing at this plant necessitated testing
during the entire furnace heat. Typical furnace operations here included
a 15 to 20-minute delay between heats. The indoor observers used this
time as a break to avoid undue eye fatigue.
D.2 MONITORING SYSTEMS AND DEVICES
There are currently no instrumental or automated systems available
for suitably quantifying the mass of fugitive emissions from secondary
BOPF control devices. These emissions are uncontained and thus not
suitable for representative sampling by any material capture technique.
These difficulties apply both to the emission sources around the steel
processing hardware and to emissions passing through the roof monitor.
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Consideration could be given to the use of-opacity transmissometers
for measuring roof monitor emissions. Practical problems render the
application of this type instrument highly questionable. A long path
transmissometer mounted to cover the full length of a roof monitor could
be used to monitor opacity, but the values measured would have to be
instrumentally or mathematically corrected to the short dimension of the
roof monitor. Since multiple plumes of varying opacities are typical at
these sources, any correlation between Method 9 observations and trans-
missometer output would be highly questionable.
The exhaust velocity in the secondary control device ducting for steel
processing plants could be monitored if required. These measurements could
be made either by periodic manual velocity traverses or by commercially
available flow detection devices. The cost of velocity monitoring could
range from about $100 for a half-day series of manual velocity tests to
some $5000 dollars for an automated electronic flow detector. Instru-
mental flow detectors are available for less than $500 to around $5000
depending upon the degree of precision and length of performance desired.
Compatibility with either chart type recording devices and digital data
acquisition systems are probably available on the more expensive flow
measuring instruments.
D.3 PERFORMANCE TEST METHODS
Method 9 - "Visual Determination of the Opacity of Emissions from
Stationary Sources," and Method 22 - "Visual Determination of Fugitive
Emissions from Material Processing Sources," are recommended as
appropriate for determining the level of performance of fugitive emission
control at BOPF shops in the steel processing industry.
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Both of these methods have Inherent advantages and disadvantages.
Method 9 can be used to quantify the intensity of the fugitive emissions
as the various opacity levels are determined. Since Method 9 is applied
at only 15-second intervals, it does not necessarily provide an
indication of the duration of emissions. Consequently, there is the
possibility that fugitive emission plumes lasting less than 15 seconds
would not be recorded by this method. Experience gained from the six
fugitive emissions test programs indicates that most of the emissions
observed from the roof monitors lasted well over 15 seconds and typically
lingered for 1 to 2 minutes. Therefore, the Method 9 requirement that
readings be taken at 15-second intervals does not pose a serious problem
to its application for roof monitor testing at BOPF shops.
EPA Method 22 is designed to provide quantitative determination of
the duration of fugitive emissions without measuring plume opacity. This
method is quite suitable to processes which produce visible fugitive.
emissions on an intermittent basis. It is also more suitable than
Method 9 for sources of multiple fugitive plumes because the observer does
not have to select the plume of highest opacity but merely records the
total time that any emissions are observed. Method 22 is the preferred
method for sources producing multiple fugitive plumes simultaneously.
Test data obtained at six BOPF shops in the steel industry indicate
that visible emissions test methods are applicable to the various process
sources as follows:
BOP Furnace - Method 22; furnace emissions are highly intermittent
and originate indoors so the level of lighting does not permit an accurate
determination of opacity. Establishing the observation period for
Method 22 by individual process operation is recommended.
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Iron Desulfurization - Method 22; although the sources are
typically outdoors, the multiplicity of fugitive sources make
opacity determinations quite difficult. Moreover, it is typical
for two or more of the plumes to mix within 10 feet from their
sources. The opacity of a composite plume could be difficult to
interpret.
Hot Metal Transfer - Method 22; process stations for this
operation can be either Indoors or outdoors. When indoors, lighting
levels are too low for Method 9 and when outdoors, the equipment
configuration typically gives very poor background options for
opacity determinations.
Skimming - Method 22; this operation is usually performed indoors
rendering opacity measurements impractical because of low lighting
levels.
BOPF Shop Roof Monitors - Method 9 or Method 22; typical roof
monitors over BOPF shops are suitable for either method of visible
emissions observations. It is essential that Method 9 observers
should position themselves to read across the shortest dimension of
the roof monitor and not through the long dimension from the end of
the monitor. Failure to observe this precaution in positioning would
result in a high bias in opacity determinations. Consideration could
be given to using both Methods 9 and 22 for combined performance
testing of roof monitors. A two-method test of this type would provide
a more comprehensive coverage of emission monitoring, but the cost
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effectiveness of such an approach 1s questionable. Application of
both methods for roof monitor testing would essentially double the
cost of a performance test.
The utilization of Method 9 for performance tests at BOPF shop
roof monitors is recommended. This recommendation is based on the
fact that Method 9 is a better quantifier of roof monitor emissions,
and field testing applications have indicated its suitability for
this source of emissions.
Any modification of the time base for averaging EPA-9 roof
monitor data should be considered for statistical accuracy prior
to implementation. A statistical analysis of Method 9 data
reduction options indicated that either a 6-m1nute or 3-minute
average is suitable for an accurate determination of opacity
levels.7
Secondary Emission Exhaust Systems - Methods 1 and 2; exhaust gas
velocities 1n the secondary steel processing control devices can be
tested by these two reference methods. The use of any Instrumental
or automated flow measuring devices cannot be used for testing until
a procedure for demonstrating the accuracy of such a system relative
to reference Methods 1 and 2 and performance specifications for such
a device have been established.
Costs for conducting performance tests of steel processing fugitive
emissions is estimated to range between $3,000 and $10,000 exclusive
of travel expenses. Variations in costs depend primarily upon the
number of sources requiring testing at a given plant. Testing costs
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can be minimized if observations are limited to the BOPF shop roof
monitor by Method 9 alone. Related processes not under the same
roof monitor would require testing separately. An example breakdown
for a test of a roof monitor and iron desulfurization unit follows:
ASSIGNMENT NO. PERSONS NO. DAYS MAN-DAYS
Presurvey 1 0.5 0.5
Field work 4 3 12
Data reduction 1 3 3
Report preparation 1 3 3
Management 1 0.5 0.5
Total 19.0
D.4 REFERENCES
1. EPA Report 80-BOF-3, "Emission Test Report, Kaiser Steel,
Fontana, California." Prepared by Clayton Environmental Consultants
under EPA Contract 68-02-2817, Work Assignment 26 and 27 and
Engineering-Science under EPA Contract 68-02-2815, Work Assignment 41.
2. EPA Report 80-BOF-4, "Emission Test Report, Artnco Steel,
Ashland, Kentucky." Prepared by Clayton Environmental Consultants
under EPA Contract 68-02-2817, Work Assignment 28.
3. EPA Report 80-BOF-6, "Emission Test Report, Inland Steel,
East Chicago, Indiana." Prepared by Clayton Environmental Consultants
under EPA Contract 68-02-2817, Work Assignment 30 and York Research
Corporation under EPA Contract 68-02-2819, Work Assignment 26.
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4. EPA Report 80-BOF-7, "Emission Test Report, Republic Steel,
South Chicago, Illinois." Prepared by Clayton Environmental Consultants
under EPA Contract 68-02-2817, Work Assignment 32.
5. EPA Report 80-BOF-8, "Emission Test Report, Republic Steel,
Cleveland, Ohio." Prepared by Clayton Environmental Consultants under
EPA Contract 68-02-2817, Work Assignment 33.
6. EPA Report 80-BOF-9, "Emission Test Report, Bethlehem Steel,
Bethlehem, Pennsylvania." Prepared by Clayton Environmental Consultants
under EPA Contract 68-02-2817, Work Assignment 36.
7. Hartwell, Tyler, D., "Examining the Properties of Qualified
Observer Opacity Readings Averaged Over Intervals of Less than Six
Minutes." Prepared by Research Triangle Institute under EPA Contract
68-02-1325.
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