SEPA
             United States
             Environmental Protection
             Agency
          Office of Air Quality
          Planning and Standards
          Research Triangle Park NC 27711
EPA-450/3-79-011
June 1979
             Air
   Review of Standards
   Performance for New
Stationary Sources -
  econdary Brass and
  ronze Plants

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                            EPA-450/3-79-011
 A Review of Standards
of Performance  for New
   Stationary Sources -
      Secondary Brass
    and Bronze Plants
                 by

         Edwin L Keitz and Kathyrn J. Brooks

        Metrek Division of the MITRE Corporation
          1820 Dolley Madison Boulevard
            McLean, Virginia 22102



            Contract No. 68-02-2526



          EPA Project Officer: Thomas Bibb

       Emission Standards and Engineering Division




               Prepared for

       U.S. ENVIRONMENTAL PROTECTION AGENCY
          Office of Air, Noise, and Radiation
       Office of Air Quality Planning and Standards
       Research Triangle Park, North Carolina 27711

               June 1979

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This report has been reviewed by the Emission Standards and Engineering
Division, Office of Air Quality Planning and Standards, Office of Air, Noise
and Radiation, Environmental Protection Agency, and approved for publica-
tion . Mention of company or product names does not constitute endorsement
by EPA. Copies are available free of charge to Federal employees, current
contractors and grantees, and non-profit organizations - as supplies permit
from the Library Services Office, MD-35, Environmental Protection Agency,
Research Triangle Park, NC 27711; or may be obtained, for a fee, from the
National Technical Information Service, 5285 Port Royal Road, Springfield,
VA 22161.
                     Publication No. EPA-450/3-79-011
                                    11

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                              ABSTRACT
     This report reviews the current Standards of Performance for
New Stationary Sources:  Subpart M - Secondary Brass and Bronze
Ingot Production Plants.  Emphasis is given to the state of control
technology, extent to which plants would be able to meet current
standards and future trends in the brass and bronze Industry.
Information used in this report is based upon data available as of
October 1978.  A general recommendation is made to retain the
current standard.  Other recommendations include periodic studies
of control technology for both metallic fume and fugitive emissions.
                                 iii

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                          TABLE OF CONTENTS

                                                                 Page

1.0  EXECUTIVE SUMMARY                                           1-1

1.1  Industry Outlook                                            1-1
1.2  Best Demonstrated Control Technology            '            1-2
1.3  Compliance Test Data                                        1-3
1.4  Possible Revision of Standard                               1-3

     1.4.1  Current Standard for Particulates and Opacity        1-3
     1.4.2  Extension of Standard to Other Emissions             1-3
     1.4.3  Extension of Standard to Other Process Steps         1-4

1.5  Final B.ecommendations                                       1-4

2.0  INTRODUCTION                                                2-1

3.0  CURRENT STANDARDS FOR SECONDARY BRASS AND
     BRONZE SMELTERS                                             3-1

3.1  Affected Facilities                                         3-1
3.2  Controlled Pollutants and Emission Levels                   3-1
3.3  Testing and Monitoring Requirements.                         3-2
3.4  Definitions Applicable to Secondary Brass and
     Bronze Smelters                                             3-3
3.5  Regulatory Basis for Any Waivers, Exemptions, .or
     Other Tolerances                                            3-4

4.0  STATUS OF CONTROL TECHNOLOGY                                4-1

4.1  Recent and Forecasted Economic Trends in the Industry       4-1

     4.1.1  Industry Overview                                    4-1
     4.1.2  Economic Outlook                                     4-11

4.2  Brass and Bronze Ingot Production Process Description       4-16

     4.2.1  Raw Materials                                        4-16
     4.2.2  Materials Preparation                                4-19
     4.2.3  Ingot Production                                     4-24

4.3  Pollution Potential from Ingot Production                   4-28

     4.3.1  Pollution from Mechanical and Hydrometal-
            lurgical Preparation                                 4-30

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                    TABLE OF CONTENTS (Concluded)

                                                                 Page

     4.3.2  Pollution from Pyrometallurgical Preparation         4-32
     4.3.3  Pollution from Smelting and Refining                 4-33

4.4  Control Technology Applicable to Brass and Bronze
     Furnaces                                                    4-41

     4.4.1  Fine Particulate Control Technology                  4-42
     4.4.2  Cost of Control Devices                              4-46

5.0  ANALYSIS OF POSSIBLE REVISIONS TO THE STANDARDS             5-1

5.1  Availability of Test Data                                   5-1
5.2  Indication of the Need for a Revised Standard               5-2

     5.2.1  Current Standard                                     5-2
     5.2.2  Extension to Other Emissions                         5-6
     5.2.3  Extension to Other Process Steps                     5-7

6.0  FINDINGS AND RECOMMENDATIONS                                6-1

6.1  Revision of the Current Standard                            6-1

     6.1.1  Findings Based on Control Technology                 6-1
     6.1.2  Findings Based on Economic Considerations            6-1
     6.1.3  Recommendations on Revision of Current
            Standard                              .               6-2

6.2  Extension of Standards                                      6-2

     6.2.1  Conclusions Based on Control Technology              6-2
     6.2.2  Conclusions Based on Economic and Other
            Considerations                                       6-2
     6.2.3  Recommendations on Extension of Standards            6-2

7.0  REFERENCES                                                  7-1
                                  vi

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                        LIST OF ILLUSTRATIONS

Figure Number                                                    Page

     4-1         Location of Secondary Brass and Bronze
                 Ingot Production Plants                         4-6

     4-2         Brass and Bronze Annual Ingot Production
                 Levels 1965-1975                                4-10

     4-3         Annual Copper-Based Scrap Consumption
                 Levels 1965-1975                                4-12

     4-4         Major Parts of the Brass and Bronze
                 Manufacturing Industry                          4-17

     4-5         Ingot Production Process Steps                  4-18

     4-6         Schematic of a Typical Secondary Metal
                 Blast Furnace or Cupola                         4-23

     4-7         Schematic of a Typical Stationary
                 Reverberatory Furnace            "               4-25

     4-8         Schematic of a Typical Indirect-Fired
                 Furnace                                         4-27
                                  vii

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                           LIST OF TABLES

Table Number                                                     Page

     4-1        Producers of Brass and Bronze Ingots,
                September 1978                                   4-2

     4-2        Brass and Bronze Alloys,  Chemical
                Specifications and Product Characteristics       4-7

     4-3        End Uses of Brass and Bronze                     4-8

     4-4        Structure of Secondary Copper Industry
                (1976)                                           4-13

     4-5        Commonly Used Substitutes for Copper,
                Brass and Bronze                                 4-15

     4-6        Pollution Potential from Ingot Production        4-29

     4-7        Estimated Particulate Emissions from
                Ingot Production                                 4-31

     4-8        Gaseous Emissions from a  Typical Oil Fired
                Brass/Bronze Reverberatory Furnace (60 Ton
                Furnace, Water Sprays, U-Tube Cooler,  Fabric
                Filter)                                          4^35

     4-9        Chemical Analysis of Brass and Bronze
                Baghouse Dust                                    4-36

     4-10       Melting, Boiling and Pouring Temperatures
                of Metals and Alloys                             4-38

     4-11       Gas Cleaning Equipment Performance for
                Nonferrous Metal Furnaces                        4-45

     4-12       Recent Data on Fine Particulate Control
                Devices                                          4-47

     4-13       Approximate Cost of Typical Control
                Equipment (December 1977  Dollars)                 4-48

     4-14       Estimate of Annual Capital and Operating
                Costs of Various Control  Devices If
                Installed at a Typical Secondary Brass and
                Bronze Smelter (1977 Dollars)                    4-50
                                 viii

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                     LIST OF TABLES (Concluded)

Table Number                                                     Page

     5-1        Administrative Data for American Brass Inc.
                Smelter                                          5-3

     5-2        NSPS Compliance Test Results for American
                Brass, Inc.                                      5-4

     5-3        Previous Particulate Test Data                   5-5
                                  ix

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1.0  EXECUTIVE SUMMARY




     The objective of this report is to review the New Source Perfor-




mance Standard (NSPS) for brass and bronze ingot production plants




and to assess the need for revision on the basis of developments that




have occurred since the original standard was promulgated on March 8,




1974.  A set of conclusions is presented and specific recommendations




are made with respect to EPA action in implementing changes in the



NSPS.




1.1  Industry Outlook




     In 1969, there were approximately 60 brass and bronze ingot pro-



duction facilities in the U.S.  Currently, only 35 facilities are




operational, and only one facility has become operational since the




promulgation of the NSPS in 1974.  No new facilities or modifications




are known to be currently planned or under construction.




     Ingot production has shown a steady decline from the 1966 peak




year production of 315,000 metric tons (Mg) (347,000 tons) to a low




of 160,000 Mg (186,000 tons) in- 1975, the last year for which nation-




wide statistics were published.  The decline has been caused by a de




facto decline in the demand for products made with brass or bronze




and large scale substitution of other materials or technologies for




the previously used brass or bronze.  The likelihood of a reversal of




this decline was investigated and discussed with key organizations




associated with the industry.  The opinion was unanimous that the




decline in brass and bronze ingot production and in the number of




plants operating will continue.




                                1-1

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1.2  Best Demonstrated Control Technology




     The current best demonstrated control technology, the fabric




filter, is the same as that when the standards were originally pro-




mulgated.  No major improvements in this technology have occurred




during the intervening period.




     High-pressure drop venturi scrubbers are used, to some extent,




in the brass and bronze industry, but their overall control efficien-




cy is significantly lower than that of fabric filters.  Typical effi-




ciencies are far below what would be required for adequate control




under the current NSPS.  Electrostatic precipitators have not been




used in the industry due to both the low gas flow rates and high



resistivity of metallic fumes.




     Future trends in control of fine particulates, particularly




metallic fumes, will most likely continue to indicate that the fabric



filter is the best choice for controls.  Extensive studies on both



conventional and new devices indicate two important points:  first,




fabric filters have the highest overall efficiencies of any of the



devices; and second, there is a minimum in collection efficiency in




the sizes around 0.5 nm for most control devices.  However, for fab-




ric filters, the differences between this minimum and the overall




efficiency are almost negligible.  This is a very important consider-




ation in control of metallic fumes, since most of the particles are




in this size range.
                                 1-2

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1.3  Compliance Test Data

     Only one facility has become subject to the NSPS since its orig-

inal promulgation.  This facility was tested in February 1978.  The

average test result of 16.9 milligrams/dry standard cubic meters

(mg/dscm), or 0.0074 grains/dry standard cubic feet (gr/dacf), is

lower than most of the test data used for justification of the cur-

rent standard of 50 mg/dscm (0.022 gr/dscf), but this single test is

not sufficient to draw any overall conclusion about improved control

technology.

1.4  Possible Revision of Standard

     1.4.1  Current Standard for Particulates and Opacity

     No justification exists for revision of any part of the current

standards for either particulates or opacity.  This conclusion is

based on the following considerations:

     1.  Fabric filter control technology has remained relatively
         constant since the standard was promulgated.

     2.  No new high temperature fabrics have become available.

     3.  Economic trends in the industry indicate that revision of
         the standard would have almost no impact on emissions
         throughout the nation.

     1.4.2  Extension of Standard to Other Emissions

     The only logical extensions of the standard to other emissions

would be for control of fugitive emissions and/or control of specific

particulates, such as zinc oxide.  There are no specific control

methods, either physical or chemical, for control of zinc oxide par-

ticles, although cooling of the gas stream can be employed to control

                                 1-3

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considerable metallic fume.  However, the overall efficiency of fab-




ric filters appears to control zinc oxide fumes to levels that do not




warrant consideration of specific controls.




     Fugitive emissions continue to be a problem in the brass and




bronze industry.  In most cases, these emissions are very difficult



to capture and equally difficult to measure during testing.  It was




primarily for the former reason that the current particulate standard




does not apply during pouring of the ingots.  This overall situation




has not changed in that only complete enclosure of the furnace can




result in full control of fugitive emissions.  However, EPA has in-




formation indicating that there may be additives capable of reducing




fugitive emissions during pouring (EPA, 1979).  Also improved control




of fugitive emissions may be possible through improved hood design.




Nevertheless, the negative growth of the industry does not appear to




warrant development of a fugitive emission NSPS at this time.



     1.4.3  Extension of Standard to Other Process Steps




     Two process steps during scrap preparation emit appreciable



amounts of particulates:  burning and sweating furnace operations.




Although control of such emissions is possible, industry trends indi-




cate that the impact of such control on emissions would be negligi-




ble.  Extension of the standard to any of these process steps is




unjustified at present.



1.5  Final Recommendations




     Based on the technological and economic findings presented in




this report, the following recommendations are made:




                                 1-4

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No extension or revision of either the participate or opacity
standards should be considered at the present time.

Periodic studies should be made to monitor both metallic fume
control technology and the economics of the brass and bronze
indvtstry.

Review of advances in control of fugitive emissions, particu-
larly from other metal industries, should be made periodical-
ly to determine if any workable economic techniques have been
developed.
                         1-5

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2.0  INTRODUCTION

      In Section 111 of the Clean Air Act, "Standards of Performance

for New Stationary Sources," a provision is set forth which requires

that "The Administrator shall, at least every four years, review and,

if appropriate, revise such standards following the procedure required

by this subsection for promulgation of such standards."  Pursuant to

this requirement, the MITRE Corporation, under EPA Contract No. 68-02-

2526, is to review 10 of the promulgated New Source Performance

Standards (NSPS) including secondary brass and bronze ingot production

plants.

     The main purpose of this report is to review the current second-

ary brass and bronze standards for particulates and opacity and to as-

sess the need for revision on the basis of developments that have oc-

curred or are expected to occur in the near future.  This report ad-

dresses the following issues:

     1.  A review of the definition of the present standards.

     2.  A discussion of the status of the secondary brass and bronze
         industry and the status of applicable control technology.

     3.  Analysis of compliance test results and review of level of
         performance of best demonstrated control technology for
         emission control.

     4.  Review of the impact of NSPS revision on secondary brass and
         bronze production economics, and the effect of the economic
         decline in the industry on any consideration to revise or ex-
         tend the NSPS.

   .  Based on the information contained in this report, a set of con-

clusions is presented and specific recommendations are made with re-

spect to EPA action in implementing changes in the NSPS.

                                 2-1

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3.0  CURRENT STANDARDS FOR SECONDARY BRASS AND BRONZE SMELTERS


     As a result of the 1970 Clean Air Act, New Source Performance


Standards were passed that specified allowable levels of emissions


from several industrial sources, including secondary brass and bronze


smelters (40 CFR 60).  Any secondary brass or bronze smelter under


construction on or after June 11, 1973 became subject to NSPS.  The


NSPS for secondary brass and bronze smelters were promulgated on


March 8, 1974 and were later amended October 6, 1975.


3.1  Affected Facilities


     The facilities of a secondary brass and bronze smelter that are


subject to NSPS are reverberatory and electric furnaces of 1,000 kg


(2,205 Ib) or greater production capacity, and blast (cupola) fur-


naces of 250 kg/hr (550 Ib/hr) or greater production capacity.  Also


affected by NSPS are modified secondary brass and bronze furnaces (a


furnace that has undergone a physical or operational change that in-


creases the emission rate of any pollutant) and reconstructed second-
                             \>

ary brass and bronze furnaces in which the replacement cost of com-


ponents exceeds 50 percent of the cost of building a comparable new


facility.  Since almost all brass and bronze ingot production in the


U.S. is of the secondary type, the regulation essentially governs the


entire industry.


3.2  Controlled Pollutants and Emission Levels


     Particulate matter is the pollutant to be controlled by second-


ary brass and bronze smelters under the NSPS.  In addition to a
                                 3-1

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particulate standard, an opacity standard is also set under the cur-

rent regulations.

     As stated in 40 CFR 60.132, no owner or operator of a secondary

brass and bronze smelter under construction on or after June 11,

1973, "shall discharge or cause the discharge into the atmosphere

from a reverberatory furnace any gases which:

     1.  Contain particulate matter in excess of 50 mg/dscm (0.022
         gr/dscf).

     2.  Exhibit 20 percent opacity or greater."

In addition, any blast (cupola) or electric furnace may not emit any

gases which exhibit 10 percent opacity or greater.

3.3  Testing and Monitoring Requirements

     A performance test of a secondary brass and bronze smelter must

be conducted within 60 days after the facility has achieved its maxi-

mum production rate and not later than 180 days after its initial

startup.  Such a test consists of three separate runs of which the

arithmetic mean is the result for determining compliance with NSFS.

If one of the runs is lost due to forced shutdown, failure of an ir-

replaceable portion of the sample train, extreme meteorological con-

ditions, or other circumstances beyond the operator's control, the

arithmetic mean of the remaining two runs will suffice as the perfor-

mance test result, upon approval by the administrator (40 CFR 60).

     Test methods to be used to determine compliance with NSPS are:

     1.  Method 5 for the concentration of particulate matter and the
         associated moisture content
                                 3-2

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     2.  Method 1 for sample and velocity traverses

     3.  Method 2 for velocity and volumetric flow rate

     4.  Method 3 for gas analysis.

     No monitoring requirement is set for secondary brass and bronze

smelters.

     Alternative testing equipment or procedures may be used (upon

approval by EPA) when the equipment capable of producing accurate re-

sults is not available (e.g., stack geometry and limited work space

require modification of location of the pollutant sampling train),

when unusual circumstances justify less costly procedures, or when

the plant operator prefers to use other equipment or procedures that

are consistent with current practices.

3.4  Definitions Applicable to Secondary Brass and Bronze Smelters

     Terms applicable to secondary brass and bronze smelters as de-

fined in 40 CFR 60 include:

     •  Blast furnace - any furnace used to recover metal from slag,
        which includes both the standard blast furnace and the
        cupola.

     •  Electric furnace - any furnace that uses electricity to pro-
        duce over 50 percent of the heat required in the production
        of refined brass or bronze ingots.

     •  Reverberatory furnace - any furnace in which the flame or hot
        gases from the burning fuel come in direct contact with the
        charge.  It includes those furnaces that are stationary, ro-
        tating, rocking or tilting.

     •  Testing is to be conducted during representative periods of
        furnace operation, including charging and tapping. However,
        testing during pouring of ingots is specifically excluded.
                                 3-3

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3.5  Regulatory Basis for Any Waivers, Exemptions, or Other
     Tolerances

     Standards do not apply during periods of startup, shutdown, and

malfunction.  In addition, when systems of emission reduction which

meet the particulate mass standard cannot meet the opacity limits,

the source may be exempted from the opacity standard and a higher ad

hoc opacity standard will be established for the facility (39 FR

9309, March 8, 1974).
                                 3-4

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4.0   STATUS  OF  CONTROL TECHNOLOGY




4.1   Recent  and Forecasted  Economic  Trends  in the  Industry




      The  secondary copper industry is  divided into two  categories:




(1)  producers of brass and  bronze ingot,  billet  or noncast  ingot,  all




having  a  rav material  input of brass and  bronze  scrap;  and  (2)  produ-




cers of unalloyed copper, having a raw material  input of  copper scrap




(Arthur D. Little,  1976).  The second  category is  not subject  to NSPS




under regulations, for  secondary brass  and bronze smelters and  will



.not  be  discvissed in this  report. Secondary brass  and bronze ingot




production encompasses approximately two-thirds  of all  secondary




copper  recovery*




      4.1.1   Industry Overview




      Secondary  brass and  bronze smelters  that produce brass and




bronze  ingots,  billets, or  noncast ingots are mostly small, individ-




ually owned  firms that usually consist of only one plant.  A few are




subsidiary operations  of  large mining  companies  or of conglomerates




(Arthur D. Little,  1976).




      In  1969,  there were approximately 60  U.S.  brass and bronze




ingot production facilities (U.S. Department of  Health, Education  and




Welfare,  1969).  Over  the next 7 years this figure dropped  to  37 fa-




cilities  (Arthur D. Little, 1976).   In September 1978,  the  U.S.




Bureau  of Mines listed 35 operational  facilities as shown in Table




4-1  (Schroeder, 1978). Only one of  these plants is new and subject




to NSPS (Sherman, 1978).






                                  4-1

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                              TABLE 4-1

        PRODUCERS OF BRASS AND BRONZE INGOTS,  SEPTEMBER 1978


 1.   American Brass Inc.,  P.O. Box 185, Headland,  Ala.  36345
     (new plant)

 2.   ASARCO Incorporated,  San Francisco, Calif.

 3.   ASARCO Incorporated,  Whiting, Ind.

 4.   ASARCO Incorporated,  Newark,  N.J.

 5.   ASARCO Incorporated,  Houston, Tex.

 6.   The G.A. Avril Co., Brass & Bronze Ingot  Div.,  Box
     66 Winton Place Station, 4445 Kings Run Drive,
     Cincinnati,  Ohio  45232

 7.   Bay State Refining Co., Inc., P.O. Box 269, Chicopee,
     Mass. 01021

 8.   Belmont Sm.  & Rfg. Wks., Inc., 330 Belmont  Avenue,
     Brooklyn, N.Y. 11207

 9.   Brush Wellman Inc., 17876 St. Clair Avenue, Cleveland,
     Ohio  44110  - Elmore, Ohio Plant

10.   W.J. Bullock, Inc., Box 539,  Fairfield, Ala.  35064

11.   Harry Butter & Co., Inc., 151 Mt.  Vernon  Street,
     Dorchester,  Mass. 02125

12.   Colonial Metals Co.,  P.O. Box 311,-Second & Linden
     Sts., Columbia, Pa. 17512

13.   Federal Metal Co., 7250 Division Street,  Bedford,
     Ohio  44146

14.   Benjamin Harris & Co., llth & State Sts., Chicago
     Heights, 111. 60411

15.   Interstate Sm. & Rfg. Co., 9651 S. Torrence Avenue,
     Chicago, 111. 60617
                                 4-2

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                   TABLE 4-1 (Continued)
16.  N. Kamenske & Co., Inc., Box 724, 5 Otterson Court,
     Nashua, N.H. 03061

17.  Kawecki Berylco Inds., Inc., Alloy Div.,  P.O. Box
     1462, Reading, Pa. 19603

18.  Blearny Sm. & Rfg. Corp., 936 Harrison Ave., Kearny,
     N.J. 07029

19.  H. Kramer & Co., P.O. Box 7, No. 1 Chapman Way,
     111 Segundo, Calif. 90246

20.  H. Kramer & Co., 1339-1345 W. 21st Street, Chicago,
     111. 60608

21.  R. Lavin & Sons, Inc., 3426 S. Kedzie Avenue,
     Chicago, 111. 60623

22.  Metallurgical Products Co., 810 Lincoln Ave., P.O.
     Box 598, West Chester, Pa. 19380

23.  Mishawaka Brass Manufacturing Inc., 1928 Mick Court,
     Mishawaka, Ind. 46544

24.  National Metals, Inc., Box 102, Leeds, Ala. 35094

25.  New England Sm. Works, Inc., 502 Union Street, W.
     Springfield, Mass. 01089

26.  North American Smelting Co., Marine Terminal,
     Wilmington, Del. 19899

27.  North Chicago Rfg. & Sm. Inc., 2028 S. Sheridan Rd.,
     N. Chicago, 111. 60064

28.  Phelps Dodge Inds., Inc., Lee Bros., P.O. Box 1229,
     Anniston, Ala. 36201

29.  River Sm. & Rfg. Co., P.O. Box 5755, Cleveland, Ohio  44101

30.  Roessing Bronze Co., P.O. Box 60, Mars, Pa. 16046
                                  4-3

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                        TABLE 4-1 (Concluded)
31.  S-G Metals Inds., Inc., 2nd & Riverview, Kansas
     City, Kan. 66110

32.  I. Schumann & Company, 22500 Alexander Road,
     Bedford, Ohio  44146

33.  Sipi Metals Corp., 1720 N. Elston Avenue, Chicago,
     111. 60622

34.  South Bend Sm. & Rfg. Co., 1610 Circle Avenue,
     South Bend, Ind. 46621

35.  Specialloy Inc., 4025 S. Keeler Avenue, Chicago,
     111. 60632

Source:  Schroeder, H.J., 1978.
                                  4-4

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     Most of the secondary brass and bronze smelters are located near




heavy industrial areas where both scrap supply and product customers




are available.  Figure 4-1 shows that plants are located mainly in




the northeast and north central industrial belts, with a concentra-




tion of plants in the industrial center of the South and two along




the Pacific Coast.



     4.1.1.1  Production.  The general products of secondary brass




and bronze smelters are 13.6 kg (30 Ib) ingots and copper or copper-



nickel alloy shot.  Traditionally, brass has been an alloy of copper



in which zinc is the principal alloying material, while bronze has




been a copper alloy in which tin is the largest secondary component.



Today these two terms are still used but they cover a wide range of



alloy compositions that have been developed for a variety of end




uses.  These uses take advantage of the different characteristics




possessed by the various alloys.  Table 4-2 lists the 12 categories




of brass and bronze that have been designated by the Brass and Bronze




Ingot Institute (U.S. Department of Health, Education and Welfare,




1969).  The table also.shows subcategories of the alloys along with




the chemical specifications and characteristics of each.  This list




parallels similar lists from the American Society for Testing and



Materials, the Federal Stock Catalog and the U.S. Department of



Defense.




      Brass and bronze are used in a wide variety of products found




in the marketplace.  Table 4-3 lists the principal categories of end






                                  4-5

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f
o\
      Source:   Schroeder, H.J., 1978.


      • - Existing Facility
      A - New Plant,  American Brass, Inc
                                          FIGURE 4-1
                           LOCATION OF SECONDARY BRASS AND BRONZE
                                   INGOT PRODUCTION PLANTS

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                                                                 TABLE 4-2




                                BRASS AND BRONZE ALLOTS,  CHEMICAL SPECIFICATIONS AND PRODUCT CHARACTERISTICS
Alloy
Ho. Classification
1A Tin bronze
IB Tin bronze
2A Leaded tin bronze
2B Leaded tin bronze
2C Leaded tin bronze
3A High-lead tin bronze
3B High-lead tin bronze
3C High-lead tin bronze
3D High-lead tin bronze
3E High-lead tin bronze
4A Leaded red brass
4B Leaded red brass
5A Leaded semi-red brass
SB Leaded semi-red brass
6A Leaded yellow brass
6B Leaded yellow brass
6C Leaded yellow brass
7A Manganese bronze
8A Hi-strength nang. bronze
8B Hi-strength mang. bronze
8C Hi-strength mang. bronze
9A Aluminum bronze
9B Aluminum bronze
9C Aluminum bronze
9D Aluminum bronze
IDA Leaded nickel brass
10B Leaded nickel brass
11A Leaded nickel bronze
11B Leaded nickel bronze
12A Silicon bronze
12B Silicon brass
Cu, Z
88.0
88.0
88.0
87.0
87.0
80.0
83.0
85. 0
78.0
71.0
85.0
83.0
81.0
76.0
72.0
67.0
61.0
59.0
57.5
64.0
64.0
88.0
89.0
85.0
81.0
57.0
60.0
64.0
66.5
88.0
82.0
Sn, Z
10.0
8.0
6.0
8.0
10.0
10.0
7.0
5.0
7.0
5.0
5.0
4.0
3.0
2.5
1.0
1.0
1.0
1.0

2.0
3.0
4.0
5.0

Pb. Z
1.5
1.0
1.0
10.0
7.0
9.0
15.0
24.0
5.0
6.0
7.0
6.5
3.0
3.0
1.0
1.0

9.0
5.0
4.0
1.5

Zn. Z
2.0
4.0
4.0
4.0
2.0
3.0
1.0
5.0
7.0
9.0
15.0
24.0
29.0
37.0
37.0
39.0
24.0
24.0

20.0
16.0
8.0
2.0
5.0
14.0
Fe. Z




1.0
1.0
3.0
3.0
3.0
1.0
4.0
4.0

1.5
Al. X




0.6
1.0
5.0
5.0
9.0
10.0
11.0
11.0


Mi. Z

•



2.0
4.0
12.0
16.0
20.0
25.0

Si. Z







4.0
4.0
Mn, Z




0.5
1.5
3.5
3.5
0.5
3.0

1.5
Characteristics
Corrosion resistant; good for casring.
Malleable; readily machined.
Inexpensive, corrosion-resistant, jood .for
casting and machining (useful for «ater
systems).
Moderately strong; easily machinet and
polished.
High tensile strength; corroaion-rasistaant
to sea water.
High tensile strength and harrtneei,
resistant to fatigue and high temperature
Excellent mechanical properties; i-trnish
and corrosion-resistant.
Good for casting (leaves a clean casting (
surface).
Source:   U.S. Department of Health, Education, and Welfare,  1969.

-------
uses.  In the construction sector, plumbing fittings, domestic

service tubing and water heaters account for the major part of the

consumption (Monzon, 1978).  In the transportation sector, large

amounts of brass and bronze are used in auto manufacture, ship-

building, and railroad rolling stock.  Consumer goods include washing

machines, refrigerators, radios and televisions which are considered

to be important durable goods in terms of the total U.S. economy.

                              TABLE 4-3

                    END USES OF BRASS AND BRONZE


                •  Building Construction

                   Plumbing
                   Electrical
                   Decorative

                •  Transportation

                •  Shipbuilding

                *  Electrical Industry

                •  Communications

                «  Consumer Goods

                •  Military

                   Munitions
                   Ordinance Manufacture
                   Aircraft Manufacture
                   Naval Vessel Construction
                   Signal Equipment


Sources:  Monzon, P.G., 1978; Arthur D. Little, 1976.
                                 4-8

-------
      Figure 4-2 shows brass and bronze ingot production levels from




1965 through 1975 (Arthur D. Little, 1976).  Output has shown a




steady decline from the 1966 peak year production of 315,000 Mg




(347,000 tons) to a low of 160,000 Mg (186,000 tons) in 1975.  This



decline occurred in spite of the high wartime military demand during




the late sixties and early seventies.



      4.1.1.2  Raw Materials.  Raw materials for ingot production



consist mostly of brass and bronze scrap. This scrap may be either



obsolete scrap or new scrap.  Obsolete scrap refers to items that are




no longer useful and are being recycled.  New scrap refers to



materials such as pieces, chips and shavings of alloys that result




from product fabrication.  They are generally recycled within the



industry itself for production of ingots.  Availability of scrap




plays a major role in the production of ingots.  It strongly



influences the amount and type of ingots produced at any given time.




The scrap inventory of a smelter is determined by availability,




storage capacity and operating capital.  Since. 75 percent of the cost




of purchasing scrap is in direct payment to the seller, operators of




smelters must maintain large amounts of liquid capital.  This creates




a significant economic burden for individual small plants.  The price




of scrap determines approximately 65 percent of the brass and bronze




ingot market price (Arthur D. Little, 1976).




      The cost of processing scrap before the actual ingot production




step represents 40 percent of the total cost of production.  This






                                 4-9

-------
I
M
O
01
g
H
H
O
A
CO
(0

o
A
H
ca

g
H

O
•rl
U
CO

O

£
      300
     (331)
             250
            (276)
      200
     (220)
     150
     (165)
                                                            I
          1965    1966     1967


 Source:   Arthur D. Little, 1976.
                                          1968
1969
1970

Year
1971
1972
1973
1974
1975
                                            FIGURE 4-2
                      BRASS AND BRONZE ANNUAL INGOT PRODUCTION LEVELS
                                             1965-1975

-------
figure is inversely proportional to the purity of the scrap and its



content of low boiling point metallics.




      Consumption of copper based scrap in the U.S. during the period




1965 through 1975 has been reported by EPA (Arthur D. Little, 1976).




On the average, 17 percent of this scrap is used in the secondary




brass and bronze industry (Figure 4-3).  The decline in scrap con-



sumption understandably parallels the decline in ingot production.



      4.1.1.3  Industry Capacity..  Table 4-4 presents data on the



basic structure of the secondary copper industry and each of its



three major segments including brass and bronze.  This data is based




on estimates made by Arthur D. Little (1976).  Production rates for




most brass and bronze plants range from 90 to 450 Mg/month (100 to




500 tons).  A few produce less than 90 Mg/month (100 tons) and a




slightly larger number produce between 450 and 900 Mg/month (500 to




1000 tons).  One plant produces more than 900 Mg/month (1000 tons).




The number of employees ranges from 10 to 500 per plant.  Comparison




of these data with that for the unalloyed copper plants shows clearly




that the secondary brass and bronze plants are usually small labor-




intensive facilities.  The average secondary copper plant has




approximately 570 employees and a production rate of 5575 Mg/month




(6145 tons).




     4.1.2  Economic Outlook




     In its original assessment of the economic impact of NSPS on the



secondary brass and bronze industry, EPA (1973) recognized the fact
                                  4-11

-------
I
h-1
M
           1,100
          (1,213)
       w  1,000
       5  (1,102)
       to
       3
       H
       CO
       g
       H
       M

       I
 900
(992)
 800
(882)
            700
           (772)
            600
           (661)
                                                 I
                1965
              1966
1967
1968
1969
1970
Year
1971
1972
1973
1974
1975
          Includes brass, bronze and unalloyed copper

          Source: Arthur D. Little, 1976
                                                       FIGURE 4-3
                                  ANNUAL COPPER-BASED SCRAP CONSUMPTION LEVELS"
                                                       .1965-1975

-------
                                            TABLE 4-4

                          STRUCTURE OF SECONDARY COPPER INDUSTRY (1976)
Plants
Segment3
Brass /Bronze
Copper
Other
Totals
Number
37b
7
26
70
Percent of
Indus try
53
10
37
100
Employees
Number
4,100
4,000
900
9,000
Percent of
Industry
46 ,
44
10
100
Metric
Tons /Month
19 ,000
39 ,000
1,800
59,800
Production
/ Short \
\Tons /MonthJ
(21,000)
(43,000)
(2,000)
(66,000)

Percent of
Industry
32
65
3
100
r* -
 Brass/Bronze - Producers of brass and bronze Ingots.
 Copper - Producers of unalloyed copper at secondary smelters.
 Other - Producers of secondary copper at primary smelters, refineries,  fabricators,  etc.

 The number of plants currently operating is 35 (Schroeder, 1978).


Source:  Arthur D. Little, 1976.

-------
that there were signs of a decline based on the fact that production

reached a peak in 1965 and 1966 and has declined since then.  Excess

capacity exists in the industry and few, if any, new plants will be

constructed in the future.  Inspection of the data presented earlier

in this section regarding number of plants, scrap consumption and

ingot production rates clearly shows that the decline has been far

greater than previously expected.

      This decline may be attributed to two major reasons:  the first

is a decline in market demand for certain brass and bronze products,

and the second is substitution of other materials or technologies for

the previously used brass or bronze.  Table 4-5 shows examples of

both reduced usage and substitution (Monzon, 1978).  In the future,

new technologies such as fiber optics for telephone and data

transmission may cause even further declines in brass and bronze

demand.

     The likelihood of the reversal of this decline was discussed

with several key organizations associated with the industry:

     •  U.S. Bureau of Mines (Schroeder, 1978)

     *  Association of Brass and Bronze Ingot Manufacturers
        (Stafford, 1978)

     •  Joint Committee for Government Liaison of the Brass and
        Bronze Ingot Institute and the Association of Brass and
        Bronze Ingot Manufacturers (Maudlin, 1978).

     All of these organizations are unquestionably convinced that the

decline in brass and bronze ingot production and in the number of

plants operating will continue into the foreseeable future.


                                  4-14

-------
                              TABLE 4-5

                    COMMONLY USED SUBSTITUTES FOR
                      COPPER, BRASS AND BRONZE
•  Aluminum (electrical transmission, motor windings, light bulbs,
   construction)

•  Iron and stainless steel (shell casings, construction, plumbing)

•  Plastics (construction, plumbing, decorative items)

•  Other (communications satellites, cryogenic superconductors)

•  Reduced copper usage

      •  Pulse code modulation increases communications
         capacity per unit mass of metal.  In 1925 1 km
         of. speech circuit used 85 kg copper.  In 1975
         only 0.17 kg was required.

      •  Between 1945 and 1975 the amount of copper in the average
         automobile was reduced 50 percent.


Source:  Monzon, 1978.
                                 4-15

-------
4.2  Brass and Bronze Ingot Production Process Description*

     Brass and bronze ingot production is one of the three major parts

of the industrial process, as shown in Figure 4-4. The raw materials

used in ingot production are almost entirely derived from scrap

materials with virgin metals used only to adjust the composition of

the product as desired.  These raw materials are subjected to a series

of sorting, classification and preparation steps before undergoing the

actual ingot production process.  The ingots produced are generally

further processed by rerneIting, shaping, rolling, extruding, etc. in

brass or bronze mills to produce final products or intermediate

products for delivery to brass and bronze manufacturing facilities.

     The basic steps in the ingot production process are shown in

Figure 4-5.  There is some functional overlap between the raw ma-

terials collection and ingot production parts of the industry in

the materials preparation steps, particularly the mechanical.  Scrap

dealers and brokers generally do some of the mechanical preparation

since the value of the scrap is usually a function of its freedom from

impurities and uniformity of composition.

4.2.1  Raw Materials

     Scrap materials used in brass and bronze ingot production are

usually gathered from one of three sources:  "home," industrial or

obsolete scrap.  "Home" scrap refers to material recycled from ingot
*The material presented in Section 4.2 has been summarized in part
 from several references:  Herrick, 1969; Jones, 1972; EPA, 1973a,
 1977; and Arthur D. Little, 1976.

                                4-16

-------
                RAW
             MATERIALS
             COLLECTION
  INGOT
PRODUCTION
  PRODUCT
FABRICATION
I
I-*
^»l
                                          FIGURE 4-4
                MAJOR PARTS OF THE BRASS AND BRONZE MANUFACTURING INDUSTRY

-------
                         PREPARATION
PRODUCTION
00


MECHANICAL









— ».



HYDRO-
METALLURGICAL

- SORTING

- STRIPPING

- SHREDDING
- MAGNETIZING

L BRIQUETTING
(OPTIONAL)

— »>


PYRO-
METALLURGICAL
(OPTIONAL)
- CONCENTRATING







— >•


SMELTING
AND — ». INGOTS
REFINING
- SWEATING

- BURNING

- DRYING
- BLAST FURNACE
- REVERBATORY
FURNACES

- ELECTRIC
FURNACES
- FUEL FIRED
CRUCIBLE
•- CUPOLA FURNACES
                                            FIGURE 4-5
                                 INGOT PRODUCTION PROCESS STEPS

-------
producers and refiners.  It is called "home" scrap because the materi-




al is recycled directly within the ingot production facilities.  It




consists of new alloys that are leftover after the production of



desired castings, machinings or other materials.




     Industrial scrap is essentially the same as "home" scrap except




that it is recycled to ingot producers from outside sources.  The




recycling may be direct from source to ingot producer (captive indus-



trial scrap) or indirect through scrap dealers or brokers (free indus-




trial scrap). In either case the scrap is free of impurities and



requires little preparation before charging into ingot production fur-




naces.




     Obsolete scrap is composed principally of used materials being




recycled through scrap dealers.  This type of scrap usually contains




significant: amounts of undesirable materials such as oil, grease,




paint, insulation and/or chemicals.  This scrap requires much more




preparation than the previous two types and has the potential for




release of greater amounts of pollutants during the early steps of




ingot production.  Obsolete scrap may be quite uniform in composition




as received, particularly if obtained in large quantities from speci-




fic industrial sources.  However, it may also be extremely nonuniform




if collected in small amounts or from diverse sources.




     4.2.2  Materials Preparation




     The basic purpose of the entire material preparation step, wheth-




er done by a scrap dealer or ingot producer, is to prepare a charge
                                  4-19

-------
for the ingot furnace that will produce the desired alloy ingot in the


most cost-effective manner.  This implies a twofold process:  one is


the removal of undesirable materials, both non-metallic and metallic;


the other is obtaining a mixture of metals as close as possible to the


composition of the desired product.  This process avoids the necessity


of removing and possibly losing valuable but unwanted metals or the


necessity of adding virgin metals to adjust the alloy.


     Ingot producers sometimes have the option of operating in one of


two modes.  They may choose only to purchase the type of scrap that


best fits their current production needs, or they may alter their pro-


duction to produce the type of alloy best suited to the scrap current-


ly available.  Obviously the market for ingots and availability of


scrap have a great influence on these options.
                                                   •

     4.2.2.1  Mechanical Preparation.  Mechanical preparation of scrap


generally involves some or all of the following steps:


     1.  Hand sorting


     2.  Stripping


     3.  Shredding


     4.  Magnetizing


     5.  Briquetting


     Since brass and bronze scrap usually consists of large pieces


rather than fine particles or dusts, the potential for air pollution


during these steps is very low except for small particles of impuri-


ties produced during shredding.  Briquetting generally has the
                                 4-20

-------
opposite effect of shredding due to the compactness of the material




and subsequent ease of handling and charging to furnaces.




     4.2.2.2  Hydrometallurgical Preparation.  In this process, which




is used occasionally, the difference in density of desirable and unde-




sirable parts of the scrap provides the means for separation in a




water medium.  This method is most advantageously used for recovery of




fine particle metallics not easily separated by one of the dry meth-




ods.  Obviously, there is a potential for water pollution if this




method is used.




     4.2.2.3  Pyrometallurgical Preparation.  The following methods




all involve the use of heat in varying amounts for preliminary proces-




sing of brass and bronze scrap.  The only methods covered under the




present NSPS are use of the blast furnace or cupola.




     1.  Sweating




     2.  Burning



     3.  Drying




     4.  Blasting furnace




     5.  Cupola




     Sweating furnaces are used primarily to remove valuable low-




melting-point metals such as lead, solder and babbitt.  If sufficient




quantities of such metals are in the scrap, this is a profitable step.




Furnace temperatures are kept relatively low to avoid loss of any of




the desirable higher-melting-point alloys.  This procedure is being




used less and less due to the smaller quantities of such metals found




with modern brass and bronze scrap.





                                 4-21

-------
     Burning is used to remove insulation, wrappings and other spe-



cialized materials from the scrap which usually consists of wire.




This process also may remove flammable oils, greases and the like from



the scrap.  This process obviously has a high potential for air pollu-




tion.  In addition, some of the materials burned may release toxic




substances.  Common examples of controversial materials are fluoro-




carbons and polyvinyl chloride.  Some ingot producers will not accept




scrap from dealers if it contains substantial amounts of polyvinyl




chloride.



     Drying furnaces are used to vaporize substances such as cutting




fluids from machine shop scrap.  The temperature of this operation is




critical since excessively high temperatures cause unwanted oxidation




on the surface of the metal chips.



     The terms blast furnace and cupola are often used interchange-



ably.  However, the cupola is used to melt down metals or reduce metal




oxides, while the blast furnace is used for reduction of metal oxides




or smelting of virgin ores.  These reducing operations cannot be done



in reverberatory or refining furnaces due to the different composi-




tion of the interacting atmosphere.  Coke is used as both a fuel and




reducing agent.  Such furnaces are also used to recover metal from




skimmings and slags.  The resulting product (black copper or cupola




melt) is impure and must be refined in other furnaces to produce brass




and bronze ingots.




     A schematic of a blast furnace is shown in Figure 4-6. The blast




furnace and cupola operate on a continuous feed basis with charge





                                 4-22

-------
     CHARGING
       DOOR
  COKE CHARGES

 METAL CHARGES


     COKE BED

     WIND BOX

      TUYERES

SLAG
SPOUT
  SUPPORTS
                                               TO CONTROLS
                                               AND STACK
                       FIGURE 4-6
        SCHEMATIC OF A TYPICAL SECONDARY METAL
               BLAST FURNACE OR CUPOLA
                           4-23

-------
material, coke and fluxes introduced at the top.  Finished metal is




drawn off from the bottom generally on an intermittent basis.  Slag is




usually tapped on a continuous basis through a separate spout at a




level immediately above the metal pouring height.  The potential for




release of particulates from such furnaces is quite high if control




devices are not used.




     4.2.3  Ingot Production




     The production of brass and bronze ingots takes place in one of




three basic types of furnaces, direct-fired reverberatory, indirect-




fired or electric.  Only the reverberatory and electric furnaces are




covered by the NSPS, since the indirect-fired furnaces are usually




small in size and produce significantly less pollutants per unit of




charge.



     4.2.3.1  Reverberatory Furnaces.  Any furnace in which the burner




flames and/or hot gases come in direct contact with the charged mate-



rial is considered to be of the reverberatory type.  Figure 4-7 is a




schematic of a typical stationary reverberatory furnace.  Such fur-




naces may also be of the rotating, rocking or tilting type, and all




operate in the batch mode.  The basic principles of operation are the




same for all types.  The charge material and fluxes may be introduced




via end, side or top access.  Charging may be completed before firing




(preferable from a pollution standpoint) or continue periodically



throughout the heat.  The fuel burned is either oil or natural gas in




combination with atmospheric or compressed air or, in special cases,






                                 4-24

-------
                  TO CONTROLS

                  AND STACK
f
N>
Ul
                CHARGING

                 DOOR
                                                                                     SLAG SPOUT


                                                                                     TAPPING

                                                                                      SPOUT
                                                  FIGURE 4-7
                              SCHEMATIC OF A TYPICAL STATIONARY REVERBERATORY
                                                  FURNACE

-------
enriched with oxygen.  In some of the furnaces the bed slopes toward




the tapping spout location and the burning fuel and hot gases flow in




a counter direction with the exhaust stack on the opposite end.




     The stationary furnaces are usually larger in size (100- to 200-




Mg capacity) than the other types which may have capacities ranging




from 0.45 Mg (a.1000 Ib) to 90 Mg (-ulOO tons).  The rotary and rocking




furnaces have the advantage of distributing the impact of the slag




layer over a greater surface of the furnace's refractory lining.




Since the slag is the principal contributor to deterioration of this




lining, spreading the contact surface prolongs the life of the lining




with obvious economic benefit.  The advantage of the tilting furnace




lies in the ease of charging, slagging and tapping.




     In all cases, when the charge attains the proper heat and impuri-



ties have been drawn off into the slag, the molten metal is tested for




its alloy composition. Adjustments are made as needed and the metal is



brought to the ideal pouring temperature for the specific alloy by




regulating the output of the fuel burners.  At this point the pouring




of the ingots begins.




     4.2.3.2  Indirect-Fired Furnaces.  On the average, indirect-fired




furnaces are significantly smaller than reverberatory furnaces and are




usually used either in small foundaries or for special purpose alloys




in small batches.  These may be crucibles of the tilting, pit or sta-




tionary type as well as the smaller low temperature pot furnaces.




Figure 4-8 shows the general operation of all of these types of






                                 4-26

-------
STATIONARY OR
MOVABLE HOOD
                                TO CONTROLS
                                    COVER
              TtttTt
                NATURAL GAS
                   OR
                 OIL HEAT
                FIGURE 4-8
   SCHEMATIC OF ATYPICAL INDIRECT-FIRED FURNACE
                     4-27

-------
furnaces.  Charge materials are introduced through the top of the



furnace along with inert fluxes. These fluxes are used to protect the




melt from the atmosphere rather than interact with the molten metal.




Finished alloys are removed from the furnaces through the top either




by tilting- and pouring or by use of ladles. The crucible furnaces are




generally used for metals up to approximately 1300°C (2400°F), while




the upper limit of pot furnaces is about 760°C (1400°F).




     4.2.3.3  Electric Furnaces.  Electric furnaces are similar in




function to indirect-fired furnaces.  Their principal advantages lie




in better furnace atmosphere control and higher temperature operation



(EPA, 1973a). Operating temperatures may reach as high as 3300°C




(6000°F).  However, since electric furnaces are more costly to operate




than oil or natural gas furnaces they are generally only used for



small, special purpose applications.  Heating may be accomplished by



direct or indirect-arc (depending on whether the current flows through



the molten metal or above it), by induction or by resistance. In all




cases, charging and ingot pouring is generally done through the top of




the furnace.




4.3  Pollution Potential from Ingot Production




     The various process steps that occur at a brass and bronze ingot




plant may create a variety of air, water and solid waste pollution




problems.  Table 4-6 summarizes the potential for such problems from




each of the major process steps.  The characteristics and extent of




emissions to the air depend on the composition of the scrap and other






                                 4-28

-------
                                                 TABLE 4-6 f

                                 POLLUTION POTENTIAL FROM INGOT PRODUCTION
                                                   Preparation
                                Mechanical
                 Hydro-
              Metallurgical
                   Pyro-
                Metallurgical
                 Production

                Smelting and
                  Refining
      Stack Emissions
None
None
High
High
ro
vo
      Fugitive Emissions
      Water Pollution
Low
None
None
High
High
None*
High
None*
      Solid Waste
Low
High
High
High
      *Unless wet scrubber or water cooling used (not common).

-------
charged materials, the fuel used, the desired temperature, the type of

furnace, the desired alloy and various operating factors such as meth-

ods of charging, slagging, alloying and pouring ingots.

     An estimate of the total particulate emissions after application

of typical controls from various pyrometallurgical and smelting steps

has been given for the year 1968 (Midwest Research Institute, 1971).

These figures are shown in Table 4-7 along with MITRE projections for

1975.  These projections were based on a comparison of 1968 and 1975

brass and bronze ingot production levels as given by EPA (Arthur D.

Little, 1976).  These figures are obviously small compared with the

total U.S. particulate emissions of 17.7xl06 Mg (19.5xl06 tons)

for 1974 (Council of Environmental Quality, 1975).

     4.3.1  Pollution from Mechanical and Hydrometallurgical
            Preparation

     Raw materials handling and mechanical preparation of scrap has a

very low potential for emission of air pollutants.  Most of the scrap

is in the form of pipes, chunks, castings and the like which are

unlikely to cause problems.  Smaller scrap containing borings, chips

and grindings is usually coated with cutting oils which greatly reduc-

es the likelihood of dust or particulate emissions.  When dry slags

are recycled there may be some fugitive dust; but it is judged to be

of minor impact (Herrick, 1969).

     Hydrometallurgical processes have a high potential for water pol-

lution if the discarding of used water is not carefully controlled.

In addition, disposal of other wastes may create a solid waste


                                 4-30

-------
                              TABLE 4-7
        ESTIMATED PARTICULATE EMISSIONS "FROM INGOT PRODUCTION

                     Emissions After Typical Controls  (Mg/yr  (tons/yr)
Process Step                  1968                   1975

Wire Burning             11,800 (13,000)a        7,250  (8,000)

Sweating Furnace            113 (125)               68  (75)

Blast Furnace               680 (750)              408  (450)

Smelting Furnace          4,990 (5,500)          3,000  (3,300)


Totals                   17,583 (19,375)        10,726  (11,825)

aMITRE Projections.
Source:  Midwest Research Institute, 1971.
                                  4-31

-------
problem.  However there is no potential for air pollutants from any of




the hydrometallurgical processes.




     4.3.2  Pollution from Pyrometallurgical Preparation




     Pyrometallurgical preparation of scrap releases the greatest




amount of particulate matter of any of the secondary brass and bronze




production procedures.  As can be seen from Table 4-7, 72 percent of




the emissions are from pyrometallurgical processes.  After allowance




for blast furnaces, which are regulated by NSPS, the remainder from




wire burning and sweating furnaces still constitutes the major frac-




tion of particulate emissions (68 percent of the total brass and




bronze emissions).




     During wire burning the major portion of the emissions will come




from the insulation on the wire and the accompanying oils and greases



(Herrick, 1969).  Source tests conducted in Los Angeles have shown




uncontrolled emissions as high as 6.6x10^ mg/dscm (29 grains/dscf)



(EPA, 1973).  This constitutes the largest single source of particu-




lates in the entire brass and bronze industry.  In addition, the emis-




sions may contain significant amounts of hazardous and/or toxic sub-




stances such as reactive hydrocarbons, fluorides and the combustion




products of common polymers such as polyvinylchloride.




     Sweating furnaces operate at fairly low temperatures so that the




metal fume losses are very low.  Due to the nature of the scrap, fumes




and combustion products of antifreeze residues, soldering salts and




hose connections are likely to be emitted (Herrick, 1969).  This will






                                 4-32

-------
be in addition to the expected oils and greases associated with such

material.

     When drying furnaces are used to remove cutting oils from chips

and borings, a potential for hydrocarbon emissions exists.  Unless

combustion in the furnace is complete enough to produce inert emission

products, controls such as afterburners may have to be considered.

     Fumes and dust from blast furnaces and cupolas are basically sim-

ilar to that from the ingot furnaces. However, since blast furnaces

and cupolas are generally used to concentrate low-grade scrap, slag

and skimmings, the ratio of nonmetallic particles to metallic fumes is

considerably higher.  Since the nature of the feed material is likely

to be quite variable, this ratio will vary as well as the total quan-

tity of the emissions.  Herrick (1969) reports uncontrolled emissions

ranging from 16 kg (35 lb)/hr to 100 kg (220 lb)/hr from three blast

furnaces of unspecified size.

      4.3.3  Pollution from Smelting and Refining

     Direct-fired furnaces of the reverberatory and rotary type will

produce larger quantities of metallic fumes such as zinc oxide and

lead oxide than the indirect-fired furnaces.  This is due to  the

impingment of the hot burner flames and gases directly on the charge

resulting in the vaporization of larger quantities of the lower boil-

ing point metals.  According to EPA (1973) other factors causing rela-

tively large fume concentrations are:

     •  Alloy composition -the rate of loss of zinc is approximately
        proportional to the zinc concentration in the alloy.

                                 4-33

-------
     •  Pouring temperature - an increase of 55°C (^100°?) in pouring
        temperature increases the rate of loss of zinc about
        three times.

     •  Poor foundry practice - improper combustion, charging at max-
        imum temperature, heating the charge too fast and insufficient
        flux cover will all contribute to excessive emissions.

     The concentration and characteristics of the emissions will vary

as a function of both the fuel (energy) used and the stage of the

ingot production cycle.  Electric furnaces have no emissions that are

due to the type of energy used.  Fuel-fired furnaces may or may not

have emissions based on the fuel used.  The choice of fuel is usually

made on the basis of the lowest projected cost at the time of furnace

construction.  Some facilities may have combination burners that allow

switching between natural gas and fuel oil based on current availabil-

ity and cost.  Natural gas is essentially pollution-free, but fuel

oils may cause some emissions.  If combustion practices are not care-

fully controlled, these fuels may emit soot, smoke and unburned hydro-

carbons.  The likelihood of significant amounts of sulfur emissions is

quite small since number two fuel oil is generally low in sulfur con-

tent and in addition, the presence of sulfur is undesirable in any

copper metal or alloy production.  The producers try to obtain the

lowest possible sulfur content fuel.  Table 4-8 presents gaseous emis-

sions from a typical oil-fired brass and bronze reverberatory furnace

(Hardison and Herington, 1970).  The data show that except for a small

amount of carbon monoxide, no significant amounts of any gaseous pol-

lutants are released.  Data obviously represent gaseous emissions from
                                 4-34

-------
                              TABLE 4-8

       GASEOUS EMISSIONS FROM A TYPICAL OIL FIRED BRASS/BRONZE
        REVERBERATORY FURNACE (60 TON FURNACE,  WATER SPRAYS,
                   U-TUBE COOLER, FABRIC FILTER)
     Species                                  Composition


     02                                        18-19% Weight

     C02                                       0.6-0.9% Weight

     CO                                        20-23 ppm

     S02                                      <1 ppm

     N02                                     •*! ppm

     H2S                                      <1 ppm

     Hydrocarbons                            <»4. ppm

     Halogens                                 <1 ppm

     N2, H20, Inerts                           Remainder



Source:  Hardison and Herlngton, 1970.
                                 4-35

-------
both the fuel burned and from the charged materials.  It can be seen




that emissions of fluorides (halogens) and reactive hydrocarbons are




very small as opposed to the high potential for such emissions during




wire burning and other pyrometallurgical preparation.




     As stated previously, the potential for particulate emissions




both primary (through the stack) and secondary (fugitive) varies with




the stage of the production cycle, which may be divided into five




parts:  charging, melting, refining, alloying and pouring.




     In general, the ratio of metallic fumes to other particulate




substances in the emissions will increase as the production cycle




proceeds.  This is due to the constant elimination of the impurities




in the charge which account for the. bulk of the nomnet alii c




participates. The exception to this is the possibility that some of



the nonmetallic particulates may be emitted from the various fluxes



added to the furnace.



     Table 4-9 shows the chemical composition of dust recovered from a




fabric filter used on a brass and bronze furnace.




                              TABLE 4-9




         CHEMICAL ANALYSIS OF BRASS AND BRONZE BA6HOUSE OUST
Substance
Zinc
Lead
Tin
Copper
Chlorine
Sulfur
Remainder (oxygen as oxide,
Composition (Z Weight)
45-77
1-12
0.3-2
0.05-1
0.5-1.5
0.1-0.7
etc.) 5.8-53
     Source :  Herrick, 1969.




                                 4-36

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Zinc, generally in the form of zinc oxide, predominates the dust.

Table 4-10 shows the melting and boiling temperatures of various

metals along with the preferred metallurgical pouring temperature for

copper and several common categories of brasses and bronze.  The data

show that zinc has the lowest boiling point (907°C/1665°F) of any of

the metals commonly found in the furnace charge. In addition, this

temperature is several hundred degrees lower than the pouring temper-

ature of copper and most of the brasses and bronzes.

     Particle size ranges for brass and bronze metallic fumes and

oxides have been reported in several references (Herrick, 1969; Mid-

west Research Institute, 1971; EPA, 1973).  Minimum size was consis-

tently reported as 0.03  m with maximum size ranging from 0.3 to 0.5

fim.

     4.3.3.1  Emissions During Charging.  The quantity and type of

emissions released during furnace charging are quite variable.  The

principal factors which cause this variation are:

     •  Metallic composition of the scrap

     •  Quantity and type of oils, greases and other impurities in the
        scrap

     •  Location of the charging doors

     •  Extent of time required to complete the charge

     •  Burner settings during charging.

     Scrap charges with high zinc content and/or high volatile or com-

bustible impurity content will produce greater amounts of both stack

and fugitive emissions during charging.  The location of charging

                                 4-37

-------
                                  TABLE 4-10

       MELTING, BOILING AND POURING TEMPERATURES OF METALS AND ALLOYS
Substance
Mercury
Arsenic
Aluminum Brass
Magnesium Brass
Cadmium
Zinc
Magnesium
Barium
Copper

Bronze

High Zinc Brass
•High Lead Brass
High Nickel Brass

Antimony
Bismuth
Lead
Tin
Aluminum
Chromium
Boron
Nickel
Cobalt
Manganese
Beryllium
Iron
Molybdenum
Tungsten
Melting Temperature
"C (°F)
-39
(-38)
817 (1503) (28 atm.)


321
419
651
725
1083







631
271
328
232
660
1890
2300
1453
1495
1244
1278
1535
2610
3410


(610)
(786)
(1204)
(1337)
(1981)







(1168)
(520)
(622)
(450)
(1220)
(3434)
(4172) '
(2647)
(2723)
(2271)
(2332)
(2795)
(4730)
(6170)
Boiling
Temperature
"C (°F)
357
613(1135)


765
907
1107
1140
2595







1380
1560
1744
2270
2467
2482
2550
2732
2900
2907
2970
3000
5560
5927
(675)
(sublimes)


(1409)
(1665)
(2025)
(2084)
(4703)







(2516)
(2840)
(3171)
(4118)
(4473)
(4500)
(4622)
(4950)
(5252)
(5265)
(5378)
(5432)
(10040)
(10701)
Approximate
Pouring Temp. Reference
°C ("F)


730 (1346)
760 (1400)




1100-1200
(2000-2200)
1100-1200
(2000-2200)
1150(2100)
1200(2200)
1300-1325
(2375-2425)














a
a
b
b
a
a
a
a
a, c

c

b
b
b

a
a
a
a
a
a
a
a
a
a
a
a
a
a
^Handbook of Chemistry and Physics, 1973.
DEPA, 1977.
      1973a.

-------
doors also plays a key role.  Overhead doors permit much larger losses




of gas, ash and fume into uncontrolled areas around the furnace.  This




is particularly true when charging is done at intervals allowing cool




scrap and impurities to contact the already molten metal in the fur-




nace.  It is usually difficult to place the entire charge into the




furnace at one time, thus necessitating interval charging to some




extent.  The emissions can be reduced somewhat if burners are turned



off or lowered during charging, particularly if the scrap is known to




be very oily.




     4.3.3.2  Emissions During Melting.  After charging is completed,




the furnace is closed and emissions are released only through the




normal flue and stack system.  This period of rapid maximum heating re-




leases large quantities of metal fume and the end products of combus-




tible impurities.  Some control over the release of the latter can be




exercised by proper air and burner settings, but the primary objective



is rapid melting of the scrap.




     4.3.3.3  Emissions During Refining.  Refining is that step in the




process during which all remaining impurities and other constituents




in excess of specifications are removed or chemically reduced.  Refin-




ing methods vary depending on the type of furnace, composition of the




scrap and the desired alloy, but' the basic approach is the same for




all.  Depending on the above factors, various fluxes such as solids,




liquids and gases are used in refining.  Compressed air is the most




extensively used flux.  Blowing air into the molten metal causes






                                 4-39

-------
selective oxidation of metals in accordance with their position in the




electromotive series.  The air blowing also oxidizes the remaining im-




purities.  The metal oxides are entrapped in the slag covering or en-




trained in the furnace exhaust gases.  In some cases nitrogen is used




to remove entrained gases, oxides of impurities, or to mechanically




and buoyantly lift foreign matter out of the metal bath.  During this




entire process part of the zinc is unavoidably oxidized and removed




along with the impurities, thus leading to the high zinc content of




the emissions.




     In general, the types of solid or liquid fluxes used do not con-




tribute to air pollution.  Rather, they are beneficial since they pre-




vent excessive metal volatilization and serve as a collector for most




of the impurities.




     4.3.3.4  Emissions During Alloying.  Alloying is the step during




which the molten metal is adjusted to the desired alloy composition by



addition of special scrap or virgin metals.  Since ingot producers




prefer to achieve the desired alloy by initial charging with the pro-




per type of scrap, this step is employed as little as possible.  Since




additional materials are added through charging doors, emissions of




fugitive metallic fumes are quite likely.  The quantity of fumes emit-




ted depends to a great extent on the percentage of zinc in the desired




alloy.




     4.3.3.5  Emissions During Pouring.  Methods of pouring the ingots




vary but significant commonality exists.  In all cases the alloyed
                                 4-40

-------
metal is brought to a preferred pouring temperature specific to the




particular alloy.  Slag covers are used on any transfer vessels such




as ladles especially for high-zinc alloys.  However, during actual




pouring large quantities of metal fumes are emitted.  After pouring,




the ingot molds are usually .covered with some material such as char-




coal to prevent metal oxidation and to produce smooth ingots.  The



application of the charcoal generally produces a shower of hot partic-




ulates which are largely uncontrolled.  All of the methods used for




pouring ingots are extremely difficult to control adequately since the



hooding of movable equipment can be quite complex.  This difficulty




was recognized during the previous background study of NSPS for




secondary brass and bronze and was acknowledged by the fact that the



pouring cycle is exempt from the particulate testing procedure for




reverberatory furnaces.




4.4  Control Technology Applicable to Brass and Bronze Furnaces



     The control of particulates and the reduction of opacity at brass




and bronze ingot production plants is in reality a single problem.  It




is generally acknowledged that for most industrial processes good con-




trol of particulates will automatically result in low plume opacities.




A report on the stack exit mass loadings which would yield no visible




emissions from various industrial processes (Beach, 1973) shows that




for zinc fume from a zinc smelter melting operation using a fabric




filter control, a stack exit emission level of 22.8 mg/actual cubic




meter (acm) or 0.010 grains/actual cubic foot (acf) at 204°C  (400°F)
                                 4-41

-------
should result in no visible emissions. Converting this value to stan-




dard conditions yields 36.5 mg/standard cubic meters (scm) or 0.016




grains/standard cubic feet (scf) at 20°C (68°F).  From a copper rever-




beratory furnace equipped with a fabric filter, these values are 34.2




mg/acm (0.015 grains/acf) at 288°C (550°F) or 65.5 mg/scm (0.029




grains/scf) at 20°C (68°F).  These data indicate that any brass and




bronze furnace emissions (which are similar in many ways to the zinc




and copper emissions) that are controlled to the NSPS level of 50 mg/




dry standard cubic meters (0.022 gr/dscf) would probably have very low




or no visible emissions. Based on the above reasoning, the following




paragraphs will discuss particulate control techniques only from the




standpoint of their ability to reduce particulate grain loadings and




not to eliminate or reduce visible emissions.  The latter will be



'taken for granted.




     4.4.1  Fine Particulate Control Technology



     There are five basic types of control equipment for removal of




suspended particulates from airstreams:




     1.  Settling chambers




     2.  Cyclones or centrifugal collectors




     3.  Scrubbers




     4.  Electrostatic precipitators (ESP)




     5.  Baghouses
                                 4-42

-------
     Since almost all of the particles from brass and bronze furnaces




are less than 0.5 |im, settling chambers and cyclones are of practical-




ly no value in control.  Such devices are designed for use where mini-




mum particle sizes are at least an order of magnitude larger (Midwest




Research Institute, 1971; Duncan et al., 1973; CapIan, 1977).  Thus,




such devices are limited to control of coarse particulates only or for




separation of coarse particulates from an airstream prior to entry



into other types of control equipment.




     Past experience has shown that wet scrubbers and ESPs have not



been very successful in controlling metallic fumes such as zinc oxide




when compared with fabric filters (Herrick, 1969; Squires, 1974;




Drehmel, 1977)*  High pressure drop venturi scrubbers are used to some




extent in the brass and bronze industry, but their overall control




efficiency is significantly lower than that of the fabric filters




(Jones, 1972).  Three scrubbers serving brass furnaces have reported




efficiencies between 53 and 65 percent (EPA, 1977).  These values are




far below what would be required' for adequate control under the cur-




rent NSPS.




     Electrostatic precipitators have not been used in the industry




mainly due to two factors.  Such devices are not common on gas flows




below 550 scmm (20,000 scfm) (EPA, 1977).  In addition, the efficiency




of collection of metallic fume is reduced due to the high resistivity




of such particles (Jones, 1972).
                                 4-43

-------
     The fabric filter is the device most often selected by the indus-

try.  Fortunately it works well on the fine particulates produced by

brass and bronze furnaces.  According to EPA (1977), the principal

control device used for particulate control from brass and bronze fur-

naces and cupolas is the fabric filter.  A survey made by EPA (1977)

of all the member companies of the Brass and Bronze Ingot Institute

shows that out of 57 reverberatory or electric furnaces with capaci-

ties of 1 ton or greater, 36 used fabric filter controls while the

remainder were uncontrolled.  Of the six cupola furnaces, four used

fabric filter controls, one used a wet scrubber and one was uncon-

trolled.

     The fabric filter will most likely continue to be the best choice

for control of fine particulates.  A comprehensive review of the con-

trol of particulates from nonferrous metal furnaces was given by

Squires (1974) in a report on the efficiencies of collection of vari-

ous sizes of particulates for a full range of control devices.

Table 4-11 lists these data and shows fabric filters as the most ef-

fective devices at all size ranges.

     In a recent comprehensive study of fine particle control techno-

logy (Drehmel, 1977) three conclusions were presented:

     1.  Electrostatic precipitation can achieve a minimum efficiency
         of 90 percent under appropriate resistivity of the particles.

     2.  Fabric filters will provide greater than 95 percent efficien-
         cy at all particle sizes.

     3.  New devices may be applicable mostly in special circumstanc-
         es.

                                 4-44

-------
*•
Ol
                                                 TABLE 4-11



                      GAS CLEANING EQUIPMENT PERFORMANCE  FOR NONFERROUS METAL FURNACES
Approximate Efficiency (%)
Collector
Low-Pressure Cellular
High-Efficiency Cylcones
Small Mult icy clones
Self Induced Spray
Spray Tower
Dry ESP
Wet Impingement Scrubber
Wet ESP
High-Pressure Drop Venturi Scrubber
Fabric Filter
Precoated Fabric Filters
Standard
Dust
80%>60 urn
74.2
84.2
93.8
93.5
96.3
94.1
97.9
99
99.7
99.8
>99.9
At
10 jim
62
85
96
97
96
98
99
99
99.8
99.9
>99.9
At
5 urn
42
67
89
93
94
92
97
98
99.6
99.9
>99.9
At
1 um
10
10
20
32
35
82
88
92
94
99
>99.9
      Source:  Squires, B.J. 1974.

-------
     Table 4-12 presents efficiency versus particle size for specific




collectors and applications reported in the study. The data indicate




two points; first, that fabric filters have the highest overall effi-




ciencies and, second, there is a minimum in collection efficiency in




the sizes around 0.5  m for most control devices, particularly the




ESP.  However, for fabric filters the difference between this minimum




and the overall efficiency is almost negligible.  This is a very




important consideration in control of metallic fume since most of the




particles are in the 0.5-|im range.




     4.4.2  Cost of Control Devices




     An important consideration in the selection of the best control




device is the cost associated with both the installation and opera-




tion.  The efficiencies of many types of controls can be increased by



appropriate changes in design parameters.  However, these changes are




usually accompanied by significantly higher costs.




     To compare the probable capital costs of three types of control




devices applied to brass and bronze furnaces, typical costs were cal-




culated on the assumption that they would be used on the recently




opened plant of the American Brass Company in Headland, Alabama.  This




plant is the only one that has become operational since the promulga-



tion of the NSPS.  Operational data were obtained (Alabama Air Pollu-




tion Control Commission, 1978) and used to calculate the approximate




capital costs of a dry ESP, a high pressure drop scrubber and a fiber-




glass fabric filter system.  Results are given in Table 4-13.  These






                                 4-46

-------
                                                TABLE 4-12

                              RECENT DATA ON FINE PARTICULATE CONTROL DEVICES
      Collector and Application
                                                           Collection Efficiency (%)
10    2
u.m    p.
                                                              0.7    0.6    0.5    0.4    0.3    0.1
*•
*»
ESP (Power Plant)

Hot-ESP (Cement)

Mobile Bed (TCA) Scrubber
(Power Plant)

Teflon Coated Glass Fabric
(Power Plant)

Graphite Coated Glass Fabric
(Power Plant)

Nomex (Industrial Boiler)

Orion (Lead Sintering)
                                            99.9

                                           >98
            95

           >98
                                                        99
                                                        99
98

99.6
                                                              80
                                                              99.4
                                                                     95
                          90

                          90
                                98
                                99
                                       30
 99

>98


 97


 99


 99

 99
                                              99.5
      Source:  Drehmel, D.C., 1977.

-------
                             TABLE 4-13

           APPROXIMATE COST OF TYPICAL CONTROL EQUIPMENT
                      (DECEMBER 1977 DOLLARS)
     Control                                            Total
    Equipment                                       Installed Costa
            (40,000 cfm) Dry Insulated ESP;            $220,000
2322m2 (25,000 sq. ft.)                               ($170,000)
Plate Area (Uninsulated cost In parentheses)

1134m3mln~1 (40,000 cfm) 3/16 In. thickness,           $ 72,000
No. 304 Stainless Steel Scrubber:  Pressure
Drop:  50 to 125 cm (20 to 50 in.)

n34m3min~1 (40,000 cfm) Fiberglass Fabric Filter;  .   $110,000
Air/Cloth 2.5/1; Stainless Steel, Continuous
Pressure Suction Operated with Mechanical Shakers
 Calculations based on information given by Neveril, R.B. et al. (1978)
                                 4-48

-------
calculations were based on the approach used by Neveril et al. (1978).




An overall efficiency of 99 percent was assumed for the ESP.  Addi-




tional calculations based on an efficiency of 99.9 percent raised the




required collector plate area to 3530 m2 (38,000 ft2).  This in




turn raised capital costs to $200,000 for an uninsulated unit and




$300,000 for an insulated one.




     Additional calculations for scrubbers show that for a pressure



drop of less than 50 cm (20 in.) the cost lowers to about $55,000.




Increasing the pressure drop to the range of 125 to 250 cm (50 to 100




in.) raises the cost to about $94,000.




     Calculations for the fabric filter system were based on an air-




to-cloth ratio of 2*5:1, which is typical for brass and bronze fur-




naces (Herrick, 1969).  The costs shown include the initial set of




fiberglass bags.  The coat of the bags could be as much as 2.5 times




higher if materials such as Nomex were used (Neveril et al., 1978).




This would increase the cost of the total system by $14,000 and ob-




viously increase the cost of bag- replacement..




     In a comprehensive study of the control of fine particulates




(Midwest Research Institute, 1970), extensive data were obtained on




operating costs of typical control devices.  This information was used




to estimate the annual operating cost, including maintenance, for fab-




ric filters, scrubbers and ESPs.  Table 4-14 presents these data




adjusted to 1977 dollars.  Also given are annual capital costs of con-




trols on a 7-year depreciation basis and an estimate of the possible
                                  4-49

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                                                  TABLE 4-14

                 ESTIMATE OF ANNUAL CAPITAL AND OPERATING COSTS OF VARIOUS CONTROL DEVICES IF
                   INSTALLED AT A TYPICAL SECONDARY BRASS AND BRONZE SMELTER (1977 DOLLARS)



                             High Efficiency Scrubber    High Efficiency ESP   High Temperature Fabric Filters

                                           % of Gross               % of Gross               % of Gross
                              Annual Cost    Salesa    Annual Cost    Sales3    Annual Cost     Sales3

       Capital Cost of
       Controls
       (7 yr depreciation)      10,500        0.09       31,500        0.3        15,700        0.1


.p.      Operating Costs
Cn      of Controlsb             84,700        0.7        26,180        0.2        24,640        0.2
o

       Total                    95,200        0.8        57,680        0.5        40,340        0.3
       a
        Gross sales based on annual production of 5500t (6063 tons)  selling at $2.16 per kg
        ($0.98 per Ib) - $11,880,000

        Based on data from Midwest Research Institute,  1970.

-------
annual gross sales price of brass ingots based on a linear projection




of the current American Brass operating schedule.  The cost of brass




ingots is based on projections of the cost of brass and bronze ingots




given by Arthur D. Little (1976).  These data show that the impact of




control costs on the overall industry is quite small.
                                 4-51

-------
5.0  ANALYSIS OF POSSIBLE REVISIONS TO THE STANDARDS

5.1  Availability of Test Data

     The Metrek Division of The MITRE Corporation conducted a survey

of the 10 EPA regions to determine the number and location of new or

modified facilities for 10 industrial categories subject to NSPS

(Watson et al., 1978).. Included in the survey was the secondary brass

and bronze ingot industry.  The survey also gathered all available

NSPS compliance test data for the industries and solicited the opin-

ions of regional personnel regarding all facets of the NSPS program.

At that time (November 1977 through January 1978) none of the regions

was aware of any new, modified or planned secondary brass and bronze

facilities.  In addition, no one voiced any opinion about the current

NSPS.

     Recently a survey was made of other organizations with possible

awareness of the brass and bronze industry to determine if they knew

of any new, modified or planned facilities.  This survey included:

      •  U.S. Bureau of Mines (Schroeder, 1978)

      •  Effluent Guidelines Division, EPA (Williams, 1978)

      •  Association of Brass and Bronze Ingot Manufacturers
         (Stafford, 1978)

      •  Joint Committee for Government Liaison of the Brass and
         Bronze Ingot Institute and the Association of Brass and
         Bronze Ingot Manufacturers (Maudlin, 1978).

This latter survey identified the existence of one new smelter,

American Brass Inc. of Headland, Alabama.
                                 5-1

-------
     Administrative data for the plant are presented in Table 5-1

(Sherman, 1978; Alabama Air Pollution Control Commission, 1978).  In

addition, the Alabama Air Pollution Control Commission provided a

copy of the results of the NSPS Compliance Test which was made on the

smelter in February of 1978.  These data are shown in Table 5-2.  It

is important to note that change of plant ownership does not consti-

tute an NSPS change or modification and in no way affects the valid-

ity or applicability of the test results.

      To assess this single set of test data, results of tests at

other facilities prior to promulgation of the current NSPS were gath-

ered (Table 5-3).  The American Brass average value of 16.9 mg/dscm

(0.0074 grains/dscf) is lower than most of the previous test data but

is not a sufficient basis to draw any overall conclusion about im-

proved control technology for brass and bronze furnaces.

5.2  Indication of the Need for a Revised Standard

      5.2.1  Current Standard

      At this time, there is not sufficient justification for revi-

sion of the present NSPS for reverberatory, blast or electric fur-

naces.  This applies to both the particulate and opacity standards.

These statements are based on the following considerations:

     •  Although there have been constant minor improvements in many
        types of control technology in recent years, the fabric
        filter still remains the most practical and effective device.

     •  There have been no technology breakthroughs that would pro-
        vide major improvement in current fabric filter technology.
                                 5-2

-------
                              TABLE 5-1

                   ADMINISTRATIVE DATA FOR AMERICAN
                          BRASS INC. SMELTER
Present Ownership:           American Brass Inc.
                             Box 185
                             Headland, Alabama  36345

Operational Dates:           31 August 1978 to present

Parent Corporation:          Commercial Technology, Inc.
                             3530 Forest Lane, Suite 98
                             Dallas, Texas  75234

Previous Ownership:          Sitkin Smelting and Refining, Inc.
                             Dothan, Alabama

Operational Dates:           19 May 1977 to approximately
                             15 July 1978

Previous Parent Corporation: Sitkin Smelting and Refining, Inc.
                             Box 708
                             Lewistown, Pennsylvania  17044


Sources:  Sherman, G., 1978; Alabama Air Pollution Control Commission,
          1978.
                                  5-3

-------
                              TABLE 5-2

                   NSPS COMPLIANCE TEST RESULTS FOR
                         AMERICAN BRASS, INC.
1.  Date of Compliance Test:  February 20, 1978

2.  Furnaces:  Four rotary reverberatory melting furnaces manu-
               factured by the Posey Iron Works; three with 40
               Mg (44 tons) capacity each and one with 10 Mg
               (11 tons).

3.  Control Equipment:  Lear-Siegler/Luhr Fabric Filter,
                        Model EKD, Model No. 6/2x98 (two houses)

4.  Compliance Test Results:
    Measured:  Run 1   - 24.9 mg/dscm at 1128 dscm/min
                          (0.0109 grains/dscf at 39,835 dscf/min)

               Run 2   - 17.8 mg/dscm at 1096 dscm/min
                          (0.0078 grains/dscf at 38,719 dscf/min)

               Run 3   - 8.0 mg/dscm at 1184 dscm/min
                          (0.0035 grains/dscf at 41,818 dscf/min)

               Average - 16.9 mg/dscm (0.0074 grains/dscf)

    Allowable:  50 mg/dscm (0.022 grains/dscf)

    Six-minute average visible emissions:  5%

5.  Operational Data:
    During Test:  All four furnaces operating
    Normal:       Two or three furnaces operating
    Current:      One 40 Mg (44 ton) furnace, 2- to 3 days
                  per week

Source:  Alabama Air Pollution Control Commission, 1978.
                                  5-4

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                              TABLE 5-3

                   PREVIOUS PARTICULATE TEST DATA
 Source
of Data
                    Average
 Capacity         Grain Loading

 Mg (Tons)    mg/dscm (grains/sdcf)
  EPA     Gas Rotary Reverb.

  EPA     Gas Stationary Reverb.

  EPA     Gas Stationary Reverb.

  EPA     Oil Rotary Reverb.

  EPA     Gas Stationary Reverb.

  EPA     Gas Rotary Reverb.

  EPA     Two Rotary Reverb.

  EPA     Two Rotary Reverb.

         'One Rotary Reverb.

  EPA   • One Rotary Reverb.

          One Blast Furnace
         *

  EPAa    One Blast Furnace

  GCIC    Two Stationary Reverb.
  6.8 (7.5)

 90.7 (100)

 54.4 (60)

 18.1 (20)

 90.7 (100)

 15.9 (17.5)

 49.9 (55) Total

 24.9 (27.5) Total   27 (0.012)

  6.8 (7.5)
 15.9 (17.5
5.5 (0.0024)

 25 (0.011)

 32 (0.014)

 25 (0.011)

 32 (0.014)

 14 (0.006)

 39 (0.017)
181.4 (200) Total
 39 (0.017)



 30 (0.013)

 64 (0.028)
  fEPA, 1973
  DEPA, 1973a
  GHardison and Herington, 1970
                                  5-5

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     •  No new high temperature fabrics have become available.

     •  Insufficient test data exist for making any new definitive
        judgements about the ability to control particulates during
        actual furnace operations. These technological factors, com-
        bined with the unfavorable economic trends in the industry
        which were discussed in Section 4.0, strongly indicate that
        no change is justified.

     5.2.2  Extension to Other Emissions

     The only logical possible extensions of the standards to other

emissions would be for control of fugitive emissions and/or control

of specific particulates such as zinc oxide.  No other emissions

either solid or gaseous appear to warrant specific regulations in

light of the declining production in this industry.

     There are no demonstrated control methods either physical or

chemical for specific control of either metallic fume or zinc oxide

in particular.  In fact fabric filters are used extensively in the

primary zinc industry to collect and recycle zinc oxide dust (Duncan

et al., 1973).  Although lowering exhaust stream temperature may in-

crease fume control and there are variables in fabric filter control

technology which result in slightly different collection efficiencies

for various specific particles  (linoya et al., 1977),  the overall

efficiency of fabric filters appears to result in control of zinc

oxide fume to levels which do not warrant consideration of specific

controls.

     Fugitive emissions continue to be a problem in many industries

including brass and bronze.  As indicated earlier the potential for
                                 5-6

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fugitive emissions from brass and bronze furnaces is quite high dur-




ing charging and pouring of ingots.  In most cases these emissions




are very difficult to capture and equally difficult to measure during



compliance tests.  It was primarily for the former reason that the




current particulate standard does not apply during pouring of the




ingots (EPA 1973).




     The control of fugitive emissions almost always becomes a prob-



lem of capturing the polluted air and passing it through an appropri-




ate control device.  Control is usually relatively easy once capture



of the airstream is made.  Effective hooding can improve capture.




However, hoods are invariably of custom design, and other operational




considerations may necessitate less than optimal hood installations.




Such considerations include access to the furnace by heavy equipment




for charging and ingot pouring.  Only complete enclosure of the fur-




nace can result in full control of fugitive emissions, and .such




extensive control does not appear economically reasonable in the




brass and bronze industry.



     5.2.3  Extension to Other Process Steps




     The only process step during reverberatory furnace operation




that is not currently controlled is the pouring of ingots.  As stated




above, this step appears at present too difficult to control by any




demonstrated economic means.  This difficulty has not changed in re-




cent years; therefore, extension of the standard to this process step




is not justified.
                                 5-7

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     Several process steps during scrap preparation emit appreciable

amounts of particulates (see Table 4-6).  These steps include wire

burning and sweating furnace operations.  From a strictly technologi-

cal point of view, control of such emissions is both possible and

justifiable.  However, two practical considerations override the

technical capability:

     •  The unfavorable economic outlook for the industry indicates
        that most likely no new facilities will be constructed before
        the next required review of the NSPS.

     •  Almost all states have general process regulations which
        should adequately control particulates and opacity from any
        new or modified facilities.

From an overall viewpoint, extension of the standard to any of these

process steps is unjustified at present.
                                 5-8

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6.0  FINDINGS AND RECOMMENDATIONS

     This report assesses the possible need for revision of the exist-

ing NSFS for secondary brass and bronze ingot production plants.

Since the control of opacity is generally directly related to the con-

trol of particulates, all conclusions are based on consideration of

the latter.

6.1  Revision of the Current Standard

     6.1.1  Findings Based on Control Technology

     •  Since the standards were originally promulgated, the fabric
        filter has remained the best demonstrated control technolo-
        gy. No major improvements in this technology have occurred
        during the intervening period.

     •  Only one compliance test result is available to assess chang-
        es in control capability.  Although results of this test were
        excellent, a far greater amount of new data would be required
        to justify any change in the standard.

     6.1.2  Findings Based on Economic Considerations

     •  The number of secondary brass and bronze smelters has
        decreased from 60 in 1969 to 37 in 1976.  Currently only 35
        smelters are operational.

     •  Only one smelter has. become operational since promulgation
        of the NSPS.  In addition, unfavorable economics required
        sale of this smelter to a new owner.  The smelter is current-
        ly operating at 30 percent of installed capacity for only 2
        to 3 days per week.  There is considerable doubt whether the
        new owner can achieve a profitable operation.

     •  Production of brass and bronze ingots in the U.S. has shown a
        sharp decline over the last twelve years.  Only occasional
        moderate increases were evident during the peak years of the
        Vietnam War when military demand was at a high level.  Pro-
        duction in 1975 was only 54 percent of the peak 1966 level.
        All available evidence indicates this decline will continue.
                                 6-1

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     6.1.3  Recommendations on Revision of Current Standard

     Based upon the technological and economic conclusions, the

following recommendations are made:

     •  No revision of either the particulate or opacity standards
        should be considered at the present time.

     •  Periodic studies should be made to monitor both metallic fume
        control technology and the economics of the brass and bronze
        industry.

6.2  Extension of Standards

     6.2.1  Conclusions Based on Control Technology

     •  Specific controls for metallic fume or zinc oxide in particu-
        lar have not been reported in this industry.  The best current
        control technology is the same as for particulates in general.

     •  Fugitive emissions continue to be difficult to capture and
        control.  Total enclosure is. the only completely workable
        method, although improved hooding or use of additives appear
        to offer the potential for improved control.

     •  Control of particulates from other process steps such as wire
        burning and sweating is technically feasible with standard de-
        vices.

     6.2.2  Conclusions Based on Economic and Other Considerations

     •  Standards for control of fugitive emissions or control of par-
        ticulates from other process steps would impose a heavy eco-
        nomic burden on an industry already in a steep decline.

     6.2.3  Recommendations on Extension of Standards

     Based upon the technological and economic conclusions stated

above, the following recommendations are made:

     •  Standards for other processes and pollutants are not required
        at the present time.

     •  Review of advances in control of fugitive emissions, particu-
        larly from other metal industries, should be made periodical-
        ly to determine if any workable economic techniques have been
        developed.

                                 6-2

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7.0  REFERENCES

Alabama Air Pollution Control Commission, 1978.  Letter from the
    Director to the MITRE Corporation.  September 12, 1978.

Arthur D. Little, 1976.  Economic Analysis of Pretreatment Standards,
    the Secondary Copper and Aluminum Subcategories of the Nonferrous
    Metals Manufacturing Point Source Category.  EPA-230/l-76-041a,
    Office of Water Planning and Standards, Washington, D.C.

Beach, G.H., 1973.  The Stack Test - Final Proof of Non-Pollution.
    Proceedings of the Specialty Conference on:  The User and Fabric
    Filtration Equipment.  Air Pollution Control Association,
    Pittsburgh, Pa.

Caplan, K.J., 1977.  Source Control by Centrifugal Force and Gravity.
    Chapter 3 in Air Pollution, 3rd Edition, Vol. IV, Engineering
    Control of Air Pollution, A.C. Stern (ed.).  Academic Press, New
    York, N.Y.

Drehmel, B.C., 1977.  Fine Particle Control Technology:  Conventional
    and Novel Devices.  Journal of the Air Pollution Control Associa-
    tion 27(2):138-140.

Duncan, L.J., E.L. Reitz and E.P. Krajeski, 1973. Selected
    Characteristics of Hazardous Pollutant Emissions. MTR-6401,
    Vol. II, MITRE Corporation, Metrek Division, McLean, Va.

Hardison, L.C. and H.R. Herington, 1970.  Study of Technical and Cost
    Information for Gas Cleaning Equipment in the Lime and Secondary
    Non-Ferrous Metallurgical Industries.  Industrial Gas Cleaning
    Institute Inc.  U.S. Air Pollution Control Office, APTD-0642,
    Research Triangle Park,. N..C.

Herrick, R.A., 1969.  Air Pollution Aspects of Brass and Bronze
    Smelting and Refining Industry.  National Air Pollution Control
    Administration Publication No. AP-58, Raleigh, N.C.

linoya, K, and C. Orr, Jr., 1977.  Filtration. Chapter 4 in Air
    Pollution, 3rd Edition, Vol. IV, Engineering Control of Air
    Pollution, A.C. Stern (ed). Academic Press, New York, N.Y.

Jones, H.R., 1972.  Pollution Control in the Nonferrous Metals Indus-
    try.  Pollution Control Review No. 13.  Noyes Data Corporation,
 ~  Park Ridge, N.J.
                                 7-1

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Maudlin, R., 1978.  Personal Communication.  Executive Secretary,
    Joint Committee for Government Liaison of the Brass and Bronze
    Ingot Institute and the Association- of Brass and Bronze Ingot
    Manufacturers•

Midwest Research Institute, 1970.  Handbook of Emissions, Effluents,
    and Control Practices for Stationary Particulate Pollution
    Sources.  MRI Project No. 3326-C, Kansas City, Mo.

Midwest Research Institute, 1971.  Particulate Pollutant System
    Study, Volume I - Mass Emissions.  MRI Project No. 3326-C, Kansas
    City, Mo.

Monzon, P.G., 1978.  Final Report, Investment in the Copper Industry
    1950-1975.  The Pennsylvania State University, Department of
    Mineral Economics, University Park, Pa.

Neveril, R.B., J.U. Price and K.L. Englahl, 1978.  Capital and Oper-
    ating Costs of Selected Air Pollution Control Systems - I.
    Journal Air Pollution Control Association 28(8):829-836.

Schroeder, H.J., 1978.  Personal Communication.  Physical Scientist
    (Copper), Division of Non-Ferrous Metals, Bureau of Mines, U.S.
    Department of Interior, Washington, D.C.

Sherman, G., 1978.  Personal Communication.  Plant Manager, American
    Brass Co., Headland, Ala.

Squires, B.J., 1974.  Fabric Filter Plants for Cleaning Gases from
    Non-Ferrous Metal Furnaces.  Filtration and Separation.
    11(3):277-288.  London, England.

Stafford, K.W., 1978.  Personal Communication.  President, Associ-
    ation of Brass and Bronze Ingot Manufacturers, West Springfield,
    Maine.

U.S. Council of Environmental Quality, 1975.  Sixth Annual Report,
    U.S. Government Printing Office, Stock No. 040-000-00337-1,
    Washington, D.C.

U.S. Department of Health, Education, and Welfare, 1969.  Control
    Techniques for Particulate Air Pollutants.  National Air
    Pollution Control Administration Publication No.  AP-51,
    Washington, D.C.

U.S. Environmental Protection Agency, 1973.  Background Information
    for Proposed New Source Performance Standard, Secondary Brass and
    Bronze, Ingot Production Plants, APTD-1352a, Volume I, Main Text.
    Office of Air and Water Programs, Research Triangle Park, N.C.
                                 7-2

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U.S. Environmental Protection Agency, 1973a.  Air Pollution Engineer-
    ing Manual, 2nd Edition.  AP-40, Office of Air and Water Pro-
    grams, Research Triangle Park, N.C.

U.S. Environmental Protection Agency, 1977.  Inspection Manual for
    Enforcement of New Source Performance Standards:  Secondary Brass
    and Bronze Ingot Production Plants. EPA 340/1-77-003.   Division
    of Stationary Source Enforcement, Washington, D.C.

U.S. Environmental Protection Agency, 1979.  Memorandum from E.E.
    Berkau, Director, Industrial Pollution Control Division to D.R.
    Goodwin, Director, Emission Standards and engineering Division.
    Subject:  A Review of the Standards of Performance for New Sta-
    tionary Sources - Secondary Brass and Bronze Plants.  8 January
    1979.

Watson, J.W., L.J. Duncan, E.L. Keitz, K.J. Brooks, 1978.  Regional
    Views on NSPS for Selected Categories.  MTR-7772,  MITRE
    Corporation, Metrek Division, McLean, Va.

Williams, P., 1978.  Personal Communication.  Effluent Guidelines
    Division, U.S. Environmental Protection Agency, Washington, D.C.
                                 7-3

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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing}
1. REPORT NO. 2.
EPA-450/3-79-Oin
4. TITLE AND SUBTITLE
A Review of Standards of Performance for New
Stationary Sources - Secondary Brass and Bronze
Plants
7. AUTHOR(S)
Edwin L. Keitz and Kathryn J. Brooks
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Metrek Division of the MITRE Corporation
1820 Dolley Madison Boulevard
Me Lean, VA 22102
12. SPONSORING AGENCY NAME AND ADDRESS
DAA for Air Quality Planning and Standards
Office of Air, Noise, and Radiation
U. S. Environmental Protection Agency
Research Triangle Park, NC 27711
3. RECIPIENT'S ACCESSION NO.
5. REPORT DATE
1 June 1979
6. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT N(
MTR-7984
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-02-2526
13. TYPE OF REPORT AND PERIOD COVEREC
14. SPONSORING AGENCY CODE
EPA 200/04
15. SUPPLEMENTARY NOTES
16. ABSTRACT
   This report reviews the current  Standards of Performance' for New Stationary
   Sources:  Subpart M - Secondary  Brass  and Bronze Ingot Production Plants.
   Emphasis is given to the  state of control technology, extent to which plants
   would be able to meet current standards,  and future trends in the brass and
   bronze industry.  Information used in  this report is based upon data available  as
   of October 1978.  A general  recommendation is made to retain the current standard,
   Other recommendations include periodic studies of control technology for bath
   metallic fume and fugitive emissions.
17. ' KEY WORDS AND DOCUMENT ANALYSIS ~~ V
1. DESCRIPTORS

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21. NO. OF PAGES
83
22. PRICE
EPA Form 2220-1 (Rev. 4-77)   PREVIOUS EDITION is OBSOLETE

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