EPA 440/1-73/008
 Development Document for Proposed
  Effluent Limitations Guidelines and
  New Source Performance Standards
              for the

     SMELTING  and SLAG

         PROCESSING
      Segment of the Ferroalloy
 Manufacturing Point Source Category
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

             AUGUST 1973

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              DEVELOPMENT DOCUMENT

                      for

    PROPOSED EFFLUENT LIMITATIONS GUIDELINES

                      and

        NEW SOURCE PERFORMANCE STANDARDS

      FOR THE SMELTING AND SLAG PROCESSING

                 SEGMENT OF THE

 FERROALLOY MANUFACTURING POINT SOURCE CATEGORY
                 Russell Train
                 Administrator

                Robert L. Sansom
Assistant Administrator for Air & Water Programs
                  Allen Cywin
     Director, Effluent Guidelines Division

              Patricia W. Diercks
                Project Officer
                September, 1973
          Effluent Guidelines Division
        Office of Air and Water Programs
      U.S. Environmental Protection Agency
            Washington, D.C.   20460

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                            Publication Notleg


This  is  a  development  document  for  proposed  effluent  limitations
guidelines  and  new  source performance  standards.  As such, this report
is subject to changes resulting from comments received during the period
of public comments of the proposed regulations.  This  document  in  its
final  form  will  be published  at  the  time the regulations tor this
industry are promulgated.

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                                ABSTRACT


For the purpose of  establishing  effluent  limitations  guidelines  and
standards  of performance for the ferroalloys industry, the industry has
been categorized on the basis of the types of  furnaces,  air  pollution
control  equipment  installed,  and  water  uses.  The categories are as
follows:

       I  Open Electric Furnaces with Wet Air Pollution Control
          Devices
      II  Covered Electric Furnaces and Other Smelting
          Operations with Wet Air Pollution Control Devices
     III  Slag Processing
      IV  Non-Contact Cooling Water

The effluent limitations to be achieved by July 1, 1977 are  based  upon
the pollution reduction attainable using those treatment technologies as
presently  practiced  by  the  average  of  the  best  plants  in  these
categories, unless present technology is uniformly inadequate  within  a
category.   The technologies are for the most part based upon the use of
•end of pipe1 treatment and once-through water usage.

The effluent limitations to be achieved by July 1, 1983 are  based  upon
the  pollution  reduction  attainable  using those control and treatment
technologies as presently practiced  by the best plant in the  category,
or readily transferrable from one industry process to another.

The  new  source performance standards are based upon the best available
demonstrated control technology, process, operating  methods,  or  other
alternatives which are applicable to new sources.

Costs  are given for the various levels of treatment identified tor each
category and for the attainment of the suggested effluent guidelines and
new source performance standards.
                                  111

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                                CONTENTS

Section                                                 Page

I      Conclusions                                        1

II     Recommendations                                    3

III    Introduction                                       7

IV     Industry Categorization                           45

V      Waste Characterization                            51

VI     Selection of Pollutant Parameters                 63

VII    Control and Treatment Technology                  65

VIII   Cost, Energy and Non-Water Quality Aspect        133

IX     Best Practicable Control Technology Currently    147
       Available, Guidelines and Limitations

X      Best Available Technology Economically           153
       Achievable, Guidelines and Limitations

XI     New Source Performance Standards and             159
       Pretreatment Standards

XII    Acknowledgements                                 165

XIII   References                                       167

XIV    Glossary                                         171

       Supplement   A                                   175

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                                FIGURES
                                                     Page

1    Ferroalloy Production Flow Diagram                20

2    Submerged-Arc Furnace Diagram                     24

3    Cross Section of Open Furnace                     25

H    Flow Sheet LC Ferrochromium                       32

5    Vacuum Furnace for Ferroalloy Production          35

6    Induction Furnace Diagram                         36

7    Plant A Water and Wastewater                      70

8    Plant B Water and Wastewater                      76

9    Plant C Water and Wastewater                      81

10   Steam/Hot Water Scrubbing System                  88

11   Plant D Water and Wastewater Systems              89

12   Plant E Water and Wastewater Systems              94

13   Plant F Water and Wastewater Systems             105

1U   Plant G Water and Wastewater Systems             .108

15   Diagram of "Wet Baghouse" System                 114

16   Plant H Water and Wastewater Systems             .115

17   Diagram of Waste Water Treatment System          121

18   Cost of Treatment Vs. Effluent Reduction         140
     Category I

19   Cost of Treatment Vs. Effluent Reduction         141
     Category II

20   Cost of Treatment Vs. Effluent Reduction         142
     Category III

21   Cost of Treatment Vs. Effluent Reduction         143
     Category IV


                                 vi

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                                 TABLES

No^                                                  Page

1    Ferroalloy Facilities and-Plant Locations         13

2    Ferroalloy Production and Shipments in 1970       12

3    No. of Plants versus Values of Shipment - 1967    14

U    Water Intake, Use, and Discharge: 1968            15

5    Water Intake by Water Use Region: 1968            15

6    Water Intake, Use, and Discharge: 1968            16

7    Intake, Use, and Discharge by Water Use           17
     Region: 1968

8    Intake Water Treatment Prior to Use: 1968         18

9    Water Treated Prior to Discharge: 1968            18

10   Material Balance for 50% Ferrosilicon         .    26

11   Ferromanganese Charge Materials-Flux Method       27

12   Ferromanganese Charge Materials - Self-Fluxing    28
     Method

13   MC Ferromanganese Charge Materials                29

m   Silicomanganese Charge Materials                  29

15   Charge Materials for HC Ferrochromium             30

16   Raw Material Components to Smelting Products      31
     for HC FeCr

17   Typical Furnace Fume Characteristics              38

18   Production and Emission Data for Ferroalloy       42 .
     Furnaces

19   Types of Air Pollution Systems Used on American   43
     Ferroalloy Furnaces

20   Illustrative Off-Gas Volumes from Open and Closed Furnaces
                                                       41
21   Raw Waste Loads-Open Chromium Alloy and           54
     Ferrosilicon Furnaces with Steam/Hot
     Water Scrubbers
                                 vii

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22   Raw Waste Load - High Energy Scrubber                   55
     On Open Electric Furnace

23   Raw Waste Loads-Open Chromium Alloy Furnaces            55
     with Electrostatic Precipitators

24   Raw Waste Loads for Covered Furnaces with               56
     Disintegrator Scrubbers

25   Raw Waste Loads-Sealed Silicomanganese Furnace          57
     with Disintegrator Scrubber

26   Raw Waste Load-Covered Furnaces with Scrubbers          58

27   Raw Waste Loads-Aluminothermic Smelting with            59
     Combination Wet Scrubbers and Baghouse

28   Raw Waste Loads-Slag Concentration Process              60

29   Raw Waste Loads-Noncontact Cooling Water—              61
     Submerged-Arc Furnaces

30   Raw Waste Loads-Noncontact Cooling Water—              62
     Submerged-Arc Furnaces

31   Pollutant Parameters for Industry Categories            63

32   Characteristics of Surveyed Plants                      65

33   Analytical Data -SP A- Plant A Lagoon Influent          71

34   Analytical Data -SP B- Plant A Lagoon Effluent          7^

35   Analytical Data -SP C- Plant A Cooling Tower #2         72

36   Analytical Data -SP D- Plant A Cooling Tower #1         72

37   Analytical Data -SP E- Plant A Well Water               73

38   Analytical Data -SP A-. Plant B Intake Water             73

39   Analytical Data -SP.B- Plant B Wet Scrubbers            77

40   Analytical Data -SP C- Plant B Thickener Inlet          77

41   Analytical Data -SP D- Plant B Thickener Overflow       78

42   Analytical Data -SP E- Plant B Cooling Water            78

43   Analytical Data -SP F- Plant B Sewage Plant             79
     Effluent

                                viii

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44   Analytical Data -SP G- Plant B Total Plant           79
     Discharge

45   Analytical Data -SP A- Plant C Well Water            82

46   Analytical Data -SP B- Plant C Cooling Tower         82
     Slowdown

47   Analytical Data -SP C- Plant C Spray Tower Sump      83

48   Analytical Data -SP D- Plant C Thickener Under-      83
     flow

49   Analytical Data -SP E- Plant C Sewage Plant          84
     Effluent

50   Analytical Data -SP F- Plant C Sludge Lagoon         84
     Effluent
                i
51   Analytical Data -SP G- Plant C Thickener Overflow    85

52   Analytical Data -SP A- Plant D Well Water            85

53   Analytical Data -SP B- Plant D Cooling Tower         90
     Slowdown

54   Analytical Data -SP C- Plant D Slurry Blend Tank     90

55   Analytical Data -SP E- Plant D Continuous Blow-      91
     down

56   Analytical Data -SP D- Plant D Filter Supply         91
     Tank

57   Analytical Data -SP F- Plant D Plant Discharge       92

58   Analytical Data -SP A- Plant E Furnace A             95
     Scrubber Discharge

59   Analytical Data -SP B- Plant E Furnace B             95
     Scrubber Discharge

60   Analytical Data -SP C- Plant E Metals Refining       95
     Scrubber Discharge

61   Analytical Data -SP D- Plant E Slag Shotting         96
     Wastewater

62   Analytical Data -SP E- Plant E Furnace C             97
     Scrubber Discharge

63   Analytical Data -SP F- Plant E Furnace D             97
     Scrubber discharge


                                  ix

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64   Analytical Data -SP G- Plant E Furnace E             98
     Scrubber Discharge

65   Analytical Data -SP H- Plant E Furnace E             98
     Scrubber Settling Basin Discharge

66   Analytical Data -SP I- Plant E Slag                  99
     Concentrator Wastewater

67   Analytical Data -SP J- Plant E Slag                  99
     Tailings Pond Discharge

68   Analytical Data -SP K- Plant E Lagoon #3            100
     Influent

69   Analytical Data -SP L- Plant E Lagoon #3            100
     Effluent

70   Analytical Data -SP M- Plant E Intake River         101
     Water

71   Analytical Data -SP N- Plant E Cooling Water        101
     Discharge

72   Analytical Data -SP O- Plant E Combined Slag        102
     Shotting & Cooling Water Discharge

73   Analytical Data -SP P- Plant E Fly Ash              102
     Influent to Lagoon

74   Analytical Data -SP Q- Plant E Fly Ash              103
     Influent to Lagoon

75   Analytical Data -SP A- Plant F Intake Water         103

76   Analytical Data -SP B- Plant F Cooling Tower        106
     Slowdown

77   Analytical Data -SP C- Plant F Plant Discharge      106

78   Analytical Data -SP A- Plant G Intake City Water    109

79   Analytical Data -SP B- Plant G Cooling Tower        109
     Slowdown

80   Analytical Data -SP C- Plant G Spray Tower          110
     Discharge

81   Analytical Data -SP D- Plant G Settling Basin       110
     Effluent

82   Analytical Data -SP E- Plant G Plant Discharge      111

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83   Analytical Data -SP F- Plant G Slag Processing        111
     Discharge

84   Analytical Data -SP A- Plant H Intake City Water      116

85   Analytical Data -SP B- Plant H Baghouse               116
     Wastewater Discharge

86   Analytical Data -SP C- Plant H Treated Baghouse       117
     Wastewater

87   Analytical Data -SP D- Plant H Settling Lagoon        117
     Discharges

98   Analytical Data -SP E- Plant H Polishing Lagoon       118
     Discharge

89   Analytical Data -SP F- Plant H Plant Discharge        118

90   Analytical Data -SP G- Plant H Plant Well Water       119

91   Analytical Data -SP H- Plant H Cooling Water          119

92   Control and Treatment Technologies by Category        123

93  Industry Category I, Open Electric Furnace with        128
     Wet Air Pollution Control Devices

94  Industry Category II, Covered Electric Furnace and Other 129
     Smelting Operations with Wet Air Pollution Control Devices

95  Industry Category III, Slag Processing                 130

96  Industry Category IV, Noncontact Cooling Water         131

97  Treatment Level Costs on Unit of Production            136
     Basis

98  Treatment Level Costs on Wastewater Flow Basis         137

99  Scrubber Costs vs Fabric Filter Costs                  138

100 BPCTCA Effluent Guidelines Treatment Basis             148

101 Best Practicable Control Technology Currently          151
    Available Guidelines and Limitations

102 BATEA Effluent Guidelines Treatment Basis              154

103 Best Available Technology Economically                 157
    Achievable Guidelines and Limitations

104 New Source Performance Standards Basis                 160

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105 New Source Performance Standards                      163

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                               SECTION I

                              CONCLUSIONS
For the purpose of  establishing  effluent  limitations  guidelines  and
standards  of performance for the ferroalloys industry, the industry has
been categorized on the basis of the types of  furnaces,  air  pollution
control  equipment  installed,  and  water  uses.  The categories are as
follows:

       I  Open Electric Furnaces with Wet Air Pollution control
          Devices
      II  Covered Electric Furnaces and Other Smelting
          Operations with Wet Air Pollution Control Devices
     III  Slag Processing
      IV  Non-Contact Cooling Water

Other factors, such as age, size of plant, geographic location, product,
and waste control  technologies  do  not  justify  segmentation  of  the
industry  into any further subcategories for the purpose of establishing
effluent limitations and  standards  of  performance.   Similarities  in
waste  loads and available treatment and control technologies within the
categories further substantiate this.  The guidelines for application of
the effluent limitations and standards of performance to specitic plants
take into account the mix of furnace types and water uses possible in  a
single plant which directly influence the quantitative pollutional load.

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                               SECTION II

                            RECOMMENDATIONS


It  is  recommended  that  the  effluent  limitations guidelines and new
source performance standards be adopted  as  suggested  herein  for  the
ferroalloy   industry.     These  suggested  guidelines  and  performance
standards have been developed on the basis of an intensive study of  the
industry, including plant surveys,  and are believed to be reasonable and
attainable  from  the  standpoints   of  both  engineering  and  economic
feasibility.

The  application  of  these  guidelines  and  performance  standards  to
specific  plants  is  intended  to  be on the basis of a "building block"
approach to define the  effluent  limits  from  the  plant  as  a  whole.
Consider,  for  example,   a large ferroalloy plant having one or more of
the processes and/or water uses in  each category.   The  total  effluent
limitation  for  the  plant  would   be  based  upon  the  totals of each
pollutant in each category, determined by multiplying the allowable unit
load by the total production rate in that category.  It  is  recommended
that  this  method  of   application  of  the  guidelines and performance
standards be used.

It is recommended that  the industry be encouraged to  develop  or  adopt
such  pollution reduction methods as the recovery and reuse of collected
airborne particulates for recycle  to  smelting  operations  or  use  in
electrolytic  processes,   and  the   use  or  sale  of  by-products.  The
development or adoption of  better   wastewater  treatment  controls  and
operating methods should also be encouraged.

The best practicable control technology currently available for existing
point sources is as follows, by category:

        I  Physical/chemical treatment to remove or destroy
           suspended solids and potentially harmful or toxic
           pollutants,  with recycle of water at the scrubber.

       II  Physical/chemical treatment to remove or destroy
           suspended solids and potentially harmful or toxic pollutants.

      Ill  Physical/chemical treatment to remove suspended
           solids and potentially harmful pollutants.

        IV  Cooling ponds or alternate treatment to reduce
            heat load in the effluent.

The effluent limitations are based  on achieving by July 1, 1977 at least
the pollution reduction attainable  using these treatment technologies as
presently  practiced  by  the  average  of  the  best  plants  in  these

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categories.  The above -technologies are based upon the use
pipe1 treatment and once-through water usage.
                                    of   •end  of
The  30  day  average  effluent  limitations  corresponding  to the best
practicable control technology currently available are  as  follows,  by
category:
                                      II
                 kg/
                mwhr

Suspended Solids.160
Total Chromium  .0032
Hex. Chromium   .0002
Cyanide
Manganese       .032
Oil             .045
Phenol          .0032
Phosphate       .0064
Heat content
pH              6-9
mwhr
 kg/
mwhr
 lb/
mwhr
 kg/
kkg
352
007
0004
-
070
098
007
0141
.209
.004
.0003
.002
.042
.059
.004
.008
                .461  1.330
                .009   .026
                .0006
                .005
                .092   .266
                .129   .372
                .009
                .018
                             III
 lb/
 ton

2.659
 .053
                      .532
                      .745
 kg/
 mwhr

1 .343
 .027
 .002
                       376
 IV

lb/
 mwhr

2.959
 .059
 .004
                       ,828
       6-9
                 6-9
                      .161    .355
                   149,000  592,000
                     kg cal/  Btu/
                     mwhr     mwhr
                        6-9
The best available technology  economically achievable for existing point
source is as follows, by category:

       I  Partial recycle of water, with blowdown treated for removal
          of suspended  solids  and  potentially harmful or
          toxic pollutants  by  physical/chemical treatment.

      II  Partial recycle of water, with blowdown treated for removal
          of suspended  solids  and  potentially harmful or
          toxic pollutants  by  physical/chemical treatment.

     Ill  No discharge, attainable by completely recycling all
          waters after  clarification.

       V  Partial recycle of cooling water.  Blowdown to be adeguately
          treated by physical/chemical  treatment to
          remove potentially harmful pollutants before discnarge
          to surface waters.

The  effluent  limitations  are  based  on achieving by July 1, 1983, at
least  the  pollution   reduction   using these  control  and   treatment
technologies  as presently  practiced by the best plant in each category,
and using transfer of technology where  the best plant in the category is
felt to be insufficient.

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The 30 day  average  effluent  limitations  corresponding  to  the  best
available technology economically achievable for Categories 1, II and IV
are as follows:
Suspended Solids
Total Chromium
Hex. Chromium
Total Cyanide
Manganese
Oil
Phenol
Phosphate
Heat Content

PH
   Category I
kg/mwhr  Ib/mwhr

 .012     .026
 .0004    .0009
 .00001   .00002
                                       Category II       Category IV
                                    kg/mwhr  Ib/mwhr  kg/mwhr  Ib/mwhr
 ,0039
 ,0055
 ,0002
 ,0001
.0086
.012
.0003
.0002
016
0005
00001
0003
005
007
0002
0001
.035
.0012
.00002
.0006
.012
.016
.0005
.0002
      6-9
             6 -
                          .067
                          ,001
                          .00003
         .019

         .004
       7,500.
    kg-cal/mwhr
9            6 -
                  .148
                  .003
                  .00006
 .041

 .009
30,000
Btu/mwhr
9
For  Category III, the effluent limitation is no discharge o± waterborne
pollutants to navigable waters.

The new source performance standards are based upon the  best  available
demonstrated  control  technology,  process, operating methods, or other
alternatives which are applicable to new sources.  With me exception of
Category I, the best available demonstrated control technology  for  new
sources  is  the  same  as  the  best  available technology economically
achievable, which will be utilized to meet the  1983  limitations.   The
standard  of  performance  for  Category I is no discharge of waterborne
pollutants to navigable waters.  This can be met by installing dry  dust
collection  devices  (i.e.,  baghouses  or  fabric  filters)  on new open
furnaces rather than wet air pollution control devices.

The 30 day average  standard  of  performance  for  new  sources,  which
corresponds  to  the  application of best available demonstrated control
technology,  process,  operating  methods  or  other  alternatives   for
Categories II and IV are as follows:

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Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Manganese
Oil
Phenol
Phosphate
Heat Content

PH
                       Category II
                    kg/mwhr  Ib/mwhr
0.016
0.0005
0.00001
0.0003
0.005
0.007
0.0002
0.0001
0.035
0.0012
0.00002
0.0006
0.012
0.016
0.0005
0.0002
6-9
                  Category IV
                kg/mwhr  Ib/mwhr
                  ,067
                  ,001
                  ,00003
    .019

    .004
7,500.
kg cal/mwhr
         6 -
             ,148
             ,003
             ,00006
 .041

 .009
30,000
Btu/mwhr
9
For Categories I and III, the  standard of performance is no discharge of
waterborne pollutants to navigable streams.

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                              SECTION III

                              INTRODUCTION

The  Federal  Water Pollu-tion Control Act Amendments of 1972 (the "Act")
requires the United States Environmental Protection Agency  to establish
effluent  limitations  which  must  be  achieved  by  point  sources  of
discharge  into  the navigable waters of the United States.  Section 301
of the Act requires  the  achievement  by  July  1,  1977,  of  effluent
limitations  which  require  the  application  of  the "best practicable
control technology currently available," and the achievement by July  1,
1983, of effluent limitations which require the application of the "best
available technology economically achievable."

Within  one  year of enactment, the Administrator is required by Section
30U(b) to promulgate regulations providing guidelines for  the  effluent
limitations required to be achieved under Section 301 of the Act.  These
regulations  are  to  identify  in  terms of amounts of constituents and
chemical, physical, and biological characteristics of  pollutants,   the
degree  of  effluent reduction attainable through the application of the
best  practicable  control  technology  currently  available  and   best
available technology economically achievable.  The regulations must also
specify  factors  to  be  taken  into  account  in  identifying  the two
statutory technology levels and in determining the control measures  and
practices  which  are  to  be  applicable  to point sources within given
industrial categories or  classes  to  which  the  effluent  limitations
apply.

In  addition  to  his responsibilities under Sections 301 and 304 of the
Act,  the  Administrator  is  required  by  Section  306  to  promulgate
standards  of  performance  for  new  sources.   These  standards are to
reflect  the  greatest  degree   of   effluent   reduction   which   the
Administrator determines to be achievable through the application of the
"best  available  demonstrated  control technology, processes, operating
methods, or other alternatives, including, where practicable, a standard
permitting no discharge of pollutants."

The Office of Air and Water Programs  of  the  Environmental  Protection
Agency  has  been  given the responsibility by the Administrator for the
development of effluent limitation guidelines and new  source  standards
as  required  by the Act.  The Act requires the guidelines and standards
to be developed within very strict deadlines and for a  broad  range  of
industries.   Effluent  limitations guidelines under Section 301 and 304
of the Act and standards of performance for new  sources  under  Section
306  of  the  Act  will  be  developed  for  27  industrial  categories.
Moreover, each of these  industrial  categories  probably  will  require
further  subcategorization  in  order  to  provide  standards  that  are
meaningful.

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In order to promulgate the  required  guidelines  and  standards,  it  is
first  necessary  to   (a) categorize each industry;  (b)  characterize the
waste  resulting  from  discharges  within  industrial  categories   and
subcategories;  and   (c)  identify  the  range  of control and treatment
technology  within  each  industrial  category  and  subcategory.   Such
technology will then be evaluated in order to determine what constitutes
the  "best  practicable control technology currently available," what is
the "best available technology economically  achievable"  and,  for  new
sources, what is the "best  available demonstrated control technology."

In identifying the technologies to be applied under Section 301, Section
304 (b)   of  the  Act  requires  that  the  cost  of  application of such
technologies  be  considered,  as  well   as   the   non-water   quality
environmental  impact  (including energy requirements) resulting from the
application of such technologies.  It is imperative  that  the  effluent
limitations  and  standards to  be  promulgated by the Administrator be
supported by adequate,  verifiable  data  and  that  there  be  a  sound
rationale   for   the    judgments  made.   Such  data  must  be  readily
identifiable and available  and such rationale must be clearly set  forth
in the documentation supporting the regulations.

FERROALLOY MANUFACTURE

Ferroalloys  are  used  for deoxidation, alloying,and graphitization of
steel and cast iron.  In the nonferrous metal industry, silicon is  used
primarily  as  an  alloying agent  for copper, aluminum, magnesium, and
nickel.  Seventy five percent  ferrosilicon is used as a  reducing  agent
in the production of magnesium by the Pidgeon process.  Manganese is the
most  widely  used  element in  ferroalloys,  followed  by  silicon and
chromium.  Others include   molybdenum,  tungsten,  titanium,  zirconium,
vanadium, boron, and colximbium.

There  are four major methods used to produce ferroalloy and high purity
metallic additives for steelmaking.  These are  (1)  blast  furnace,   (2)
electric smelting furnace,  (3) alumino- or silicothermic process and  (U)
electrolytic  deposition.   The  choice of process is dependent upon the
alloy produced and the availability of furnaces.  Ferromanganesfc is  the
principal metallurgical form of manganese.  This product contains 75% or
more of manganese, the balance being mainly iron.  It is produced in the
blast  furnace  or  electric-arc  furnace  and  is  available in several
grades.  A few steel companies produce ferromanganese for their own  use
since  they  have  their  own  ore  sources  and suitable blast furnaces
available.  The production  of ferromanganese in blast furnaces is a part
of S.I.C. 3312 and such production is not considered herein, but will be
covered under the guidelines for the iron  and  carbon  steel  industry.
Electric smelting furnaces  produce most of the ferroalloy tonnage.

The  majority  of electric  ferroalloy furnaces are termed submerged arc,
although the mode of energy release in many cases is resistive  heating.
Raw  ore,  coke,  and  limestone or dolomite mixed in proper proportions

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constitute the charge for the electric-arc  furnace  process.    A  large
supply   of  electric  power  is  necessary  for  economical  operation.
Important  operating  considerations   include   power   and   electrode
requirements,  size  and  type  of furnace, amount and size o± coke,  and
slag losses.   The major ferroalloys thus produced are:

     1.  Silicon Alloys - Ferrosilicon (50-98% Si)  and Calcium
                          Silicide

     2.  Chromium Alloys - High carbon Ferrochromium in various
                           grades and Ferrochromesilicon.

     3.  Manganese Alloys - Standard Ferromanganese and
                            Sili comanganese

There are a smaller number of furnaces which do not  operate  with  deep
submergence  of the electrodes and produce a batch melt which is usually
removed by tilting the furnace.  Mix additions  and  power  input  would
usually  be  cyclic.   Examples  of  products  produced  in this type of
furnace are:

     1.  Manganese Ore-Lime melt for subsequent ladle
         reactions with silicomanganese to produce medium
         carbon and low carbon ferromanganese.

     2.  Chrome Ore-Lime melt for subsequent ladle reaction
         with ferrochromesilicon to produce low carbon ferrochromium.

     3.  Special Alloys, such as Aluminum - Vanadium, Ferrocolumbium,
         Ferroboron, Ferrovanadium and Ferromolybdenum.

The largest source of waterborne pollutants other than  thermal  in  the
industry  is the use of wet methods for air pollution control; consider-
ation of  air  pollution  sources  is  thus  of  importance  here.   The
production  of  ferroalloys  has  many  dust  or  fume  producing steps.
Particulates are emitted from  raw  materials  handling,  mix  delivery,
crushing,  grinding, and sizing, and furnace operations.  Emissions from
furnaces vary widely in type and quality, depending upon the  particular
ferroalloy being produced and the type of furnace used.

The  conventional  submerged-arc  furnace  utilizes  carbon reduction of
metallic oxides and continuously produces  large  quantities  of  carbon
monoxide.   Other  sources  of gas are moisture in the charge materials,
reducing agent volatile matter, thermal decomposition  products  of  the
raw  ore,  and  intermediate  products of reaction.  The carbon monoxide
content of the furnace off-gas varies from 50-90% by  volume,  depending
upon   the   alloy  being  produced  and  the  amount  of  turnace  feed
pretreatment.  The gases rising out the top of the furnace carry fume or
fume precursors and also entrain the finer size constituents of the  mix
or  charge.   Submerged-arc  furnaces  operate  in  steady-state and gas

-------
generation is continuous.   In  an open furnace, all  the  CO  burns  with
induced  air  at  the  top  of  the charge, resulting in a large volume of
gas.  In a covered or closed furnace most or all of the CO is  withdrawn
from  the  furnace  without combustion with air.  The controls used are
thus affected by the  type  of furnace,  the  gas  volume  and  emitted
particle size and particle  characteristics.

Fume  emission  also occurs at furnace tap holes.  Because most furnaces
are tapped intermittently,  tap hole fumes occur only about 10 to 20%  of
the  furnace  operating time.   Melting operations may be conducted in an
open arc furnace  (as opposed to a submerged arc furnace) in some plants.
While no major quantities   of   gas  are  generated  in  this  operation,
thermally induced air flow  may result in fume emission.

WATER POLLUTION SOURCES

Air  pollution  control  devices  include  baghouses, wet scrubbers, and
electrostatic precipitators.   Wet scrubbers, of course, produce slurries
containing most of the particulates in the off-gases.  Spray towers used
to cool and condition the gases before  precipitators  produce  slurries
containing  some percentage of the particulates in the gases.  Baghouses
generally produce no wastewater effluents.  In one plant,  however,  the
gases  from exothermic processes are cooled by water sprays, scrubbed in
wet dynamic scrubbers, and  finally cleaned in a baghouse  in  which  the
bags are periodically washed with water.

The only currently feasible type of wet collector for cleaning the large
gas  volume  from  open  furnaces  is  the  venturi type scrubber.  With
required pressure drops on  the order of 152.4  cm   (60  in.)  W.G. ,  the
power  consumption  approaches 10% of the furnace rating.  Most venturi
designs  allow  recirculation   of  scrubbing  liquor   so   that   water
consumption is reduced to that evaporated into the gas plus that exiting
with  the  concentrated solids stream.  The venturi has the advantage of
being able to absorb gas temperature peaks by  evaporating  more  water.
For  a ferrosilicon or ferrochromesilicon operation substantially all of
the sulfur in the reducing  agent  appears  in  the  gas  phase,  and  a
corrosion  problem  occurs  in any liquid recycle system unless neutral"
izing agents or special materials of construction are used.

Electrostatic  precipitators   have  been  installed  on  open   furnaces
producing  ferrosilicon,  ferrochromesilicon, high-carbon ferrochromium,
and silicomanganese, both in this country and abroad.   Most  ferroalloy
fumes  at temperatures below 259.7°C  (500°F) have too high an electrical
resistivity, i.e.,  greater than  1  X  1010  ohm-cm  for  the  use  of
electrostatic  precipitators.   The  resistivity is in an accepted range
only if the gas temperature is maintained  above  259.7-315=2°C   (500-
600°F).   Water  conditioning   would  lower the resistivity, but a large
spray tower is required  for   proper  humidification.   Stainless  steel
construction would be a necessity for ferrosilicon or ferrochromesilicon
                                   10

-------
operations.  The alternate use of steam is feasible if low-cost steam is
available.

The  resistivity  problem could be overcome by using a wet precipitator,
but water usage appears to be greater  than  that  for  a  wet  scrubber
without  recycle.  Wet electrostatic precipitators have been used at one
installation in Europe.  However, all parts of the precipitator  exposed
to  the  dirty  water  and  to the wet gas were constructed of stainless
steel.  Electrostatic precipitators have found limited usage in American
ferroalloy plants, although commonly used in Japan.
                                                        1
Submerged arc furnaces may be characterized as  open,  semi-closed,  and
sealed.   The latter two types may also be termed covered furnaces.  The
open furnace has no cover and air is freely available  to  burn  the  CO
coming off from the charge.  The semi-closed furnace has a cover through
which  the  electrodes extend down into the charge; the space around the
electrodes is kept filled with the charge materials to form a quasi-seal
which reduces the emissions from these locations but does not completely
prevent the escape of the gases generated.  The  sealed  furnace  has  a
similar  cover  but  with  mechanical  seals around both the electrodes,
which do prevent the escape of gases.

The sealed furnace has thus far been applied only  to  calcium  carbide,
pig iron, standard ferromanganese and silicomanganese.  In Japan, it has
also been used to produce ferrochromium, ferrochromesilicon, and 50% and
75%  ferrosilicon.   Sealed covers are difficult to adapt ro an existing
furnace because of the extensive revisions that are usually required.


The disintegrator types of scrubber was formerly often employed for  the
cleaning  of  gases  from  covered  furnaces.  Althougn it can do a good
cleaning job when properly  maintained  on  furnaces  producing  calcium
carbide,  venturi  scrubbers  do  a better job of dust removal tor other
products.  The disintegrator type  of  scrubber  has  the  advantage  of
producing  a  slight  pressure  head  (about 5 cm  (2 in.) W.G.), but the
capacity limitations and  high  water  and  power  consumption  make  it
uneconomical for most new furnace installations.  Additionally, the need
for  greater  dust  removal from furnace gases have caused disintegrator
scrubbers to be eclipsed by venturi scrubbers.

The venturi type scrubber has been installed for cleaning  CO  gas  from
covered furnaces, but the required pressure drops are high (about 152 cm
(60  in.)W.G.).   The  electrostatic  precipitator  is a possible CO gas
cleaning device, but has  found  no  such  applications  in  the  United
States,  although it is commonly used in Japan.  It is possible to use a
bag collector to clean CO gas, but only one such installation  is  known
in  the  world,  and none in this country.  A "candle filter" system for
cleaning CO gase$ in ceramic filters, is another (albeit rare)  type  of
dry dust collectors.
                                  11

-------
Other  sources  of  wastewater  in   the   industry  are  from  cooling  uses,
boiler feed, air conditioning,  and  sanitary   uses.    Wastewaters  also
result  from  slag  processing  operations   in  which slag is crushed and
sized for recovery of  metal  values, or from  slag shotting operations   in
which the slag is granulated for further  use.

PLANT LOCATIONS AND INDUSTRY STATISTICS

There are some 40 plants  in  the  United States which produce ferroalloys,
chromium, manganese, and  other additive metals  as  tabulated in  Table 1.

The  1967 _Census  of  Manufactures  reports 34 establishments  in S.I.C.
3313, i.e., primarily  engaged in the production of electrometallurgical
products.   Of  these  establishments, only  20  were included in the ±968
Water	Use^in Manufacturing  data as having used 75.7 million lirers  (20
million  gals.) or more of water annually.   The total  value of  shipments
in S.I.C.  3313  (34 plants)  in 1967 was $467.9  million.   The   value   of
shipments from the 20  large  water-using plants  was $411.4 million.

Although according to  the Minerals  Yearbook, 1^10• shipments rather than
production are the measure of activity in the industry,  as  production  in
the  high-volume  ferroalloys may be irregular  and intermittent, for air
and water pollution regulatory purposes production is  a better  indicator
of industry activity than is shipments.   Production   and   shipments   in
1970 were as shown in  Table  2.
    Table 2.  FERROALLOY PRODUCTION AND  SHIPMENTS  IN  1970
                        Production
Product

Ferromanganese
Silicomanganese
Ferrosilicon
Silvery Iron
Chromium Alloys:
  Ferrochromium
  Other
Ferrotitanium
Ferrocolumbium
Total
    islsa

  757,920
  175,285
  643,455
  178,143

  280,876
    87,238
    3,048

yTl27,~1K)8
    tons

  835,463
  193,219
  709,287
  196,369
  kkg

732,283
156,900
597,909
188,351
  309,613   262,481
   96,163    73,968
    3,360     2,985
	1,260	1^289
2,344,734 2,016,166
.Ship_me_njts	
            Value
    tons
   807,368
   172,988
   659,216
   207,664

   289,395
   81,552
     3,291
          2,222^895
134,456
 32,024
136,238
 16,853

100,667
 25,606
  3,503
	9,385
458,732"
                                   12

-------
                              Table 1.  TYPES, SIZES, AND LOCATIONS OF FERROALLOY PRODUCING PLANTS IN THE UNITED STATES
U)

Plant
Producers Size Locations
1
2
3
4
5
6

7
8
9
10
11
12
13
14
15
16
17
18
19

20

21
22
23
24
25
26
27
28
29
30

31
32
33

34
35

36

37
38
39
40
Air Reduction Co., Inc.
Airco Alloys Div.


American Potash Co.
Chromium Mining & Smelting
Co.
Climax Molybdenum Co.
Foote Mineral Co.





Hanna Nickel Smelting Co.
Interlake, Inc.
Kawucki Derylco Industries
Kawecki Chemical Co.
Luckenby
Manganese Chemicals Co.,
Diamond Shamrock
Molybdenum Corp. of America

National Lead Co.
New Jersey Zinc Co.
Ohio Ferro Alloy Corp.



Reynolds Metals Co.
Reading Alloys
Sandgate Corp.
Shieldalloy Corp.

Tennessee Alloys Corp.
Tennessee Metallurgical Co.
Union Carbide Corp.








Woodward Co.
Div. Mead Corp.
L
M
M
S
S
M

S
S
L
L
S
M
M
S
L
S
S
S
S

S

S
S
M
L
M
S
S
S
S
S

S
S
L

L
L

S

S
M
M
S
Calvert City, Ky.
Charleston, S.C.
Niagara Falls, N.Y.
Theodore, Ala.
Aberdeen, Miss.
Woodstock, Tenn

Langeloth, Pa.
Cambridge, Ohio
Graham, W. Va.
Keokuk, Iowa
Knoxville, Tenn.
Steubenville , • Ohio
Wenatchee, Wash.
Riddle, Oreg.
Beverly, Ohio.
Springfield, Oreg.
Easton, Pa.
Selma, Ala.
Kingwood, K. Va.

Washington, Pa.

Niagara Falls, N.Y.
Palmerton, Pa.
Brilliant, Ohio
Philo, Ohio
Powhatan, Ohio
Tacoma, Wash.
Lister Hill, Ala.
Robesonia, Pa.
Houston, Texas
Newfield, N.J.

Bridgeport, Ala.
Kimball, Tenn.
Alloy, W. Va.

Ashtabula, Ohio
Marietta, Ohio

Niagara Falls, N.Y.

Portland, Oreg.
Sheffield, Ala.
Rockwood, Tenn.
Woodward, Ala.
Products
FeCr, FeMn, FeSi, FeCrSi



Mn
FeMn,SiMn,FeSi,FeCr,
FeCrSi
FeMo
FeB , FeCb , FeTi , FeV , other
No.
Type of furnace Furnaces
Electric
Electric
Electric
Electric
Electrolytic
Electric

Aluminothermic
Electric
FeCr, FeCrSi, FeMn, FeSi, SiMn Electric
FeSi, Silvery Iron
Mn
FeCr, FeCrSi
FeSi
FeSi
FeCr, FeSi, SiMn
Si
FeCb
FeSi
FeMn

FeMo

FeCbTi, FeTi, other
Spiegeleisen
FeCr, FeSi, Si, FeCrSi
FeB, FeMn, FeSi, SiMn, Si
FeSi, Si
FeCr, FeSi
Si
FeB , FeCb , FeV , NiCb , FeMo
FeMn, SiMn
FeV, FeTi, FeB, FeMo,
FeCb, FeCbTa
FeSi
FeSi
FeB, FeCr, FeCrSi, FeCb ,
FeSi, FeMn
FeTi, Few, FeV, SiMn, other






FeMn, SiMn
FeSi
Electric
Electrolytic
Electric
Electric
Electric
Electric
Electric
Aluminothermic
Electric
Fused Salt Electro-
lytic
Electric & Alumino-
thermic
Electric
Electric
Electric
Electric
Electric
Electric
Electric
Aluminothermic
Electric
Aluminothermic

Electric
Electric
Electric

Electric
Electric,
electrolytic, vacuum
Electric,
aluminothermic
Electric
Electric
Electric
Electric
11
2
1
1

5


3
9
8

6
4
4
7
2

1




3
1
4
10
4
2
1

3


3
2
16

8

11

2
2
5
7
1
                   Plant size classification
                  S-Up  to 25,000 KW
                  M- 25,000 to  75,000  KW
                  L-Over 75,000 KW

-------
In  1970,  345,567  kkgs   (381,000  tons)  of  ferroalloys  were  produced  in
blast furnaces according to  the   Annual   Statistical	Report,	A.I.S^I^-
122.0=.	  Plants  using  other than  blast  furnaces  tnus  produced  about
1,781,107 kkgs  (1,963,734  tons)  in  that  year.

On the basis of the census data  and the  number of  plants  enumerated   in
Table  1,  the  distribution of.  numbers  of plants  versus capacity in the
industry appears to be  as  in Table  3.


Table 3.; NUMBER OF PLANTS  VS.  VALUES OF  SHIPMENTS-1967
                           	Value  of  Shipments^l  million),
	No. of plants	          	Ferroalloys	    	Total	

       20                        -              411.4
       34                      398.2              467.9
       40                      420.4
The large water-using  plants thus account for some   88   pcicenr  of   the
value  of  shipments   in   S.I.C.   3313,  while numbering  20  our  of 40  and
apparently account  for over  80   percent  of  the   total value  of   the
shipment of  ferroalloys.

The  1968 Water  Use in Manufacturing  data for those estabiishrnenrs using
more than 75.7 million liters (20 million gal)   of   wattr   annually   are
summarized in Tables 4 thru 9.
                                   14

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Table 4.  WATER INTAKE, USE,  AND DISCHAPGE: 1968
No. of Establishments                               20.
No. of Employees                                 8,700.
Value Added by Manufacture                        $168.9 X 106
No. of Establishments Recirculating Water          17

                                                    __ Gallons
Total Intake                           1128.7 X 10* 298.2 X  109
Intake Treated Prior to Use            3406.5 X 1 O6 900.  X  106
Total Water Discharged                 1120.7 X 109 296.1 X  109
Intake for Process                        4.9 X 109   1. 3 A  10«
Intake for Air Conditioning             757.  X 109 200.  x  109
Intake for Steam Electric  Power        701.4 X 109 185.3 X  10*
Intake for Other Cooling or  Condensing 381.5 X 1 O9 100. t) X  109
Intake for Boiler Feed, Sanitary ,  etc.  40.1 / 1 O9  10. b X  109
Table 5.  WATER INTAKE  BY WATER USE REGION: 1968
                            Intake
   _^	B§_3i2!l	J02_liters 109_gals-. Np^Esrablishmeiits
Delaware and Hudson      (D)         (D)           (D)
Eastern Great Lakes    381.5        100.8          5
Ohio River             684.3        180.8          7
Tennessee                (D)         (D)           (D)
Southeast                (D)         (D)           (D)
Upper Mississippi        (D)         (D)           (D)
Pacific Northwest        (D)         (D)           (D)
(D)  Withheld to avoid disclosing data on individual plants.
                                   15

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Tal ' 5 6.  WATER INTAKE, USE, AND DISCHARGE: 1968
Value of Shipments
                                 Liters
 X 10*

Gallons
Intake from Public Systems
Co. Surface Intake
Co. Ground Intake
Gross Water Used
Public Sewer Discharge
Surface Water Discharge
Ground Water Discharge
Transferred to other Users
Treated before Discharge
3028.
1119.
6.
1212.
1514.
1102.
1892.
15.
199.

2
,4
3

2
5
c
,4
X
X
X
X
X
X
X
X
X
1
1
1
1
1
1
1
1
1
06
09
O9
09
06
09
06
09
09
800.
295.
1.
320.
400.
291.
500.
4.
52.

7
7
3

2

1
7
X
X
X
X
X
X
X
X
X
1
1
1
1
1
1
1
1
1
06
09
09
09
06
O9
06
09
09
                                  16

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Table 7.  INTAKE, USE,  AND  DISCHARGE BY WATEF USE REGION:
Value of Shipments
$ 97.2
106
                                      Eastern
                                  Liters
     Great. Lakes
         Gallons
Intake from Public Systems
Co. Surface Intake
Co. Ground Intake
Gross Water Used
Public Sewer Discharge
Surface Water Discharge
Ground Water Discharge
Transferred to other Users
Treated before Discharge
Value of Shipments


Intake from Public Systems
Co. Surface Intake
Co. Ground Intake
Gross Water Used
Public Sewer Discharge
Surface Water Discharge
Ground Water Discharge
Transferred to other Users
Treated before Discharge
1892.
379.

379.
1514.
364.
378.
15.



L
378.
677.
6.
718.

679.
757.

157.
5
6

6

5
5
5



i
c
9
1
8

a


l
X
X
(7.)
X
X
X
X
X
(?)


ter
X
X
X
X
(Z)
X
X
-
X
1
1

1
1
1
1
1



s
1
1
1
1

1
1

1
09
09

09
06
09
06
09

$179
Ohio

06
09
09
09

09
06

09
500
100

100
400
96
100
4

.8 X
Five

100
179
1
189

179
200

41

•

•
•
•
•
.

1
r
G
•
.
•
•

•
•

•

3

3

3

1

0

a

1
6
9

5


5
X
X
(Z)
X
X
X
X
X
(Z)
6

lie
X
X
X
X
(Z)
X
X
-
X
1
1

1
1
1
1
1



>n
1
1
1
1

1
1

1
09
09

09
06
0-9
06
09



s
0*
09
09
09

09
06

09
(Z)  Less than 1.89 million  I/year (500,000 gal/year)
                                   17

-------
Table 8.  INTAKE WATER TREATMENT PRIOR TO USE: 1968
    TreatmentEstablishments     lQl_!iters IQf
Aeration                       1              -
Coagulation                    4             1.9        0.5
Filtration                     4             1.5        0.4
Softening                      4              .4        0.1
Corrosion Control              4             1.5        0.5
pH                             3
Other                          2              -
None                          13
Table 9.  WATER TREATED PRIOR TO DISCHARGE: 1968
    Treatment         Establishments     109 liters  109
Primary Settling              3               -
Secondary Settling            3
Trickling Filters             1               -
Activated Sludge              2               -
Digestion                     5               .4        0.1
Ponds or Lagoons              6            157.5       41.6
pH                            3               -
Chlorination                  3               -          -
Flotation                     3                    .      -
Other                         9
                                   18

-------
PRODUCTION PROCESSES

The ferroalloy manufacturing processes  are  listed below witn the product
groups manufactured by each process.
     Submerged-arc furnace process -
     Exothermic process -
     Electrolytic process -


     Vacuum furnace process -

     Induction furnace process
Silvery  iron
50?' Ferrosiliccn
65-75°'. Fc..:rrosilicoii
Silicon  m--t.al
Si 1 icon-ir;angan e sr- - zircom urn
"Hich-carbcn  (HC)  Ferro-
manganese
Silicomanganese
F€.-r romanqanese  silicon
Charge chrome
KC ferrccl.romium
Ferrocnrcme silicon
Calcium  carbide

Low-car bo:.  (LC)  terro-
cKroniium
1C ferromanoar.ese
IvcvGium-carbon  (MC)  ±~-rro-
incrigar.r. se
Chroii'iurr; metal
Titanium, Vanadium and
c:olumbium Alloys
Chromium metal
Manganese metal

LC ftrrochromium

Magnesium ferrosilicon
Ferrotitanium
Ferroalloy   production   in  submerged-arc  furnaces  consists  of  raw
materials preparation and handling,  smelting,   and  product  sizing  and
handling as shown in Figure 1.

RAW MATERIALS PREPARATION AND HANDLING

The  mineralogy  of  individual ores  used by the ferroalloys industry is
highly technical  and  specialized.   The  ores  must  be  analyzed  and
carefully  evaluated  to  identify   any   undesirable  elements.  Careful
evaluation of the ore is  essential   not  only  with  regard  to  costs,
including  government tariffs, since  ores are commonly sold on the basis
of contained metal or metallic oxide, but also with  regard  to  freight
charges  to  ferroalloy plants.  Other considerations in the purcnase of
ores  are  their  physical  characteristics,   ease  of  reduction,   and
analytical specifications necessary  to meet customer requirements.
                                   19

-------
                                                                                       Figure t
                                                                           FERROALLOY PRODUCTION FUDW  DIAGRAM
ro
o
                                                                                                                                                 FUMES
                                                                                         CRUSHING
                                                                                                   SCREENING
                                                                                                                 STORAGE
                                                                                                                                                     SHIPMENT

-------
The  United  States is dependent almost" entirely upon commercial sources
of manganese and chromium ores from outside the country.   inese ores are
imported mainly from South America, Africa, Turkey, India,  arid  Russia.
Since the time interval between mining  the crts and their  receipt at the
ferroalloy  plants  is usually many months, or even as long as a year,  a
substantial stock of manganese and chromium ores of the particular types
and grades necessary to produce the desired alloys must be maintained.

It is the general practice to procure ores from familiar   sources  since
their  peculiarities  will  be  Known.   Such  ores  will  nave  already
demonstrated their suitability for the  intended smelting process.  There
are not many known chromium ore deposits end their fundamental  chemical
composition  and  physical properties have betr. reasonci£/iy well defined.
The same is true of commercially mined  manganese ores.

Most ores come to the market for sale in the dressed state ana are  sold
on  the  basis  of  their  content  of  the  n.etal oxide or metai, i.e.,
contained manganese, chromium oxide, 'etc.  In general,  ores  containing
high  percentages  of  metal  oxides are ec.si-.-r to process ana result,  in
lower production costs than ores wi~h lew-r percentages or metal oxides.

In addition to chromium and mar.qanes-: ores,  columbiuiT.-^eariiiy  ores   or
slags,  titanium ores, and zirconium cr<=s are also importt=a.  Commercial
sources of vanaaium and  tungsten  tearing  cree;  exist  in  the  United
States.   High-purity  quartzes  or  quartzites with low alumina and low
iron oxide are found in selected areas  of this  country.   riiyn  quality
limestone deposits are also available domestically at a few locations.

The  chromium  ores  imported  and used for ferroalloy prouuction in the
United States have a Cr2o3^ content of   about  45  to  53   percent.   The
manganese  content  of  the manganese ores ranges from 43  to 54 percent.
Since the ores  used  for  ferroalloy   production  contain  consiaerable
gangue,  ore receipts and storage at the ferroalloy plants involve large
tonnages.

The  sizing  of  ores  is  important.   Fine,  ores,  sucn  as  flotation
concentrates,  are  not  desirable  as  a  direct  charge  into reduction
furnaces because such ores lack porosity and do not allow  tne release  of
reaction gases.  Dust losses are therefore high.  Fine ores can be  used
effectively  with  minimum  mechanical  losses  in melt furnaces and can
later be reduced with silicon alloys.   While  work  has   been  done   on
briquetting  fine  ores, equipment investment and briquetting costs have
been difficult to justify  through  increased  production  and  improved
recovery.  On the other hand, ores received at the plants  are frequently
oversized and must be crushed to a suitable size.

It  is desirable to have in storage an  adequate quantity or ore with the
desired  chemical  analysis  and  physical  properties.    i'he  desirable
quantities  stored  will  depend  on  the  furnace  capacity,  marketing
situation, and storage capacity of the  plant.  The interest on the funds


                                  21

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invested in the ores held  in   storage   ir-ay  become  a  significant  cost
factor.  Often it is possible  to  assemble ore from several sources which
will complement each other in  their composition.

The  ore shipment, plus the required quartzes cr quartzites, lime, scrap
steel turnings, and reducing agents, etc., are generally transported  to
plants  by  railway  or  river barges.   Ores are unloaded by traveling
cranes or railroad-car dumpers and moved with belt conveyors to  storage
areas.   The  free moisture in the raw  materials is significant, ranging
from 10 to 20 percent.  In some plants, the  moisture  is  decreased  by
passing the material through driers before use in furnaces.

Care  is  required  in  the  preparation  of furna'ce charges in order to
produce a specified ferroalloy.   Normally, raw materials are conveyed to
a mix house where they are weighed and  blended.   After  tne  batch  has
been  assempled,  it is moved  by  conveyors, buckets, sxip noist, or cars
to the hoppers above the furnace, where it may flow by  gravity  through
chutes to the furnaces.

SUBMERGED-ARC FURNACES

The general design of electric submerged-arc furnaces for tne production
of alloys is basically the same throughout the industry; out tney differ
in  electrical  connections,   arrangements  of electrodes, and snape and
size of the hearth.  The three carton ele^ctrode-s are arranged in a delta
formation, with the tips submerged .9-1.5 m  (3-5 ft.)  into  tne  charge
within  the furnace crucible,  so  the reduction center lies in the middle
of the charge and the reaction gases, formed in  the  reduction  center,
pass upward through the charge.   A portion of the heat is transttrred to
the  charge and partly prereduces the ore as it. passes downward into the
center of the furnace.  Because of  the passage  of  tne  reaction  gas
through the charge, fume losses are reduced.


Existing  submerged-arc  furnaces are  generally built with an open top,
and large quantities of reaction  gases  evolved  in  tue  reaction  zone
during  the  reduction  process   will flow without hindrance into a hood
built above the furnace.   The  gases burn on the surface  of  tne  charge
supported  by  the  oxygen of in-rushing  air, and are then discharged
through stack(s)  (after gas cleaning) to the  atmosphere.   Due  to  the
open  configuration,  the   parts  above the furnace, i.e., the electrode
holders, the hangers, the  current conductors,  the  charging  equipment,
etc., are exposed to the radiant  heat of the furnace and tne not furnace
gases.   These components  must receive  effective heat protection through
the use of cooling water flowing  through interior passages in the  metal
parts.  In some reduction  furnaces that produce ferroalloys water-cooled
covers  having  gas  removal   equipment are  built  over tne top of the
furnace crucible.  In such furnaces raw materials are used tnat  do  not
tend to bridge and block the flow of gas so that it is not imperative to
                                   22

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work  the charge with stoking rods.  To reduce the bridging problem, raw
materials may be pretreated.

The crucible of the submerged-arc furnace consists  of  a  sealed  metal
shell  adequately  supported  on foundations with provisions ror cooling
the steel shell.  The bottom interior o± the s-ceel shell is  linea  with
two  or  more  layers  of carbon blocks ana tightly sealed with a carbon
compound packed between the joints.  The. interior walls or  trie  furnace
shell  are lined with refractory or carton brick.  One or more tap-holes
are provided through the shell at the top level  of  the  bottom  carbon
block.   In some cases, provisions are made for the furnace to rotate or
oscillate slowly.

Figure 2 shows a diagram of a ferroalloy furnace while Figure 3 snows an
overall cross section of the same furnace with its accessory equipment.

The iron content in the ferroalloy charge material and  product  greatly
facilitates both its manufacture and use.  When metals that melt at high
temperatures  are  alloyed  with  iron,  the resulting alloy has a lower
melting temperature than the metal with the  high  melting  point.   The
lower  melting temperature greatly facilitates the furnace production of
ferroalloys and also facilitates its solution in molten steel or iron.

In the submerged-arc furnace the conversion of electrical energy to heat
takes place by current flow from the electrode tips to  the  riearth  and
between  electrodes.   Final  reduction of the oxidic ores occurs in the
lower portion of the furnace.

Submerged-arc furnaces generally operate continuously except ror periods
of power interruption or mechanical breakdown of components.   Operating
time  averages 90 to 98 percent.  The electrodes are submerged from .9 -
1. 5 m (3-5 ft.)  below the mix level, and their tips are .Located about .9
- 1.8 m (3-6 ft.) above  the  hearth.   The  electrodes'  position  thus
facilitates  both heat exchange and mass transfer between reaction gases
and the mix.

High temperatures,  up  to  2000°C   (3632°F),  are  required  to  effect
reduction  reactions.  Carbon  monoxide  is a necessary byproduct of the
smelting reaction.  In the case of silicon metal, about 2 kg (U.4 Ib)  of
carbon monoxide are produced for each kg (2.2 Ib) of metal;  significant
amounts of silicon monoxide are also produced as an intermediate.

Although furnaces may be changed from production of one product group to
another,  such  as from ferromanganese to ferrcchromium, tnis may entail
rearrangement of electrode spacing and different power loads and voltage
requirements.   It  may  also  reduce  the  efficiency  of  the  rurnace
operation,  since  most  furnaces  are  designed  to produce one type of
alloy.  However, it is relatively easy to switch from ferromanganese  to
silicomanganese, for example, since they are in the same product group.
                                  23

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                      Figure 2 .
           SUBMERGED-ARC  FURNACE  DIAGRAM
REACTION
GASES
             ELECTRODES
                     .1.
                     A
                            CHARGE
                          .— MATERIAL
                                            REFRACTORY
                                            LINING
          MOLTEN   FERROALLOY
            CARBON HEARTH
    '  l\' I  I  1 I  I  I I  1	II
   k-CRUCIBLE

CARBON
                        CARBON —'
                          24

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                                                                            CROSS SECTION OF OPEN  FURNACE
                                                                                            (f}
NJ
Ul
        TAPPING FLOOR -
                                                                     CRANE  FOR  PASTE 4
                                                                     CASING HANDLING
                                                     I'ITTII I II 1 1 I I I I I II ITTI I 1 I ! I I I ITI I I I I I ITTT1
GAS
OFFTAKE


SUPERSTRUCTURE
                                                                                                                                                OPERATING

-------
The molten alloy from the  carbon reduction of the ore accumuiares at the
base of the electrodes in  the  furnace.  The molten alloy is periodically
removed  through a tap-hole  placed to drain the 'metal from the hearth of
the furnace.
FERROSILICON PRODUCTION

Quartz  and  quartzite  are   the   minerals  mostly  used  for   smelting
ferrosilicon.  The ores should  contain not  less than 98 percent SiO2_ and
the  lowest possible content  of alumina, magnesium oxiae, calcium oxide,
and phosphorous.   The  reducing   agent  usually  used  is  cOKe;  other
reducing  agents  are  coal,  petroleum coke, and charcoal.  Tne reducing
agent should have  minimum  ash  and  phosphorous  conttnt.   The  iron-
containing  substance  should be clean, carbon steel scrap or pelletized
iron ore; the chromium and phosphorous contents should  be  low.   These
requirements preclude the use of stainless  scrap and cast iron scrap.
A  material  balance  for the  production of
as shown in Table  10.
                                           50/t ferrosilicon is rypically
            Table  10.  MATERIAL  BALANCE  FOR  50*- FERPOSILICON
                         (%  of material charged)
Quartzite
Coke
Steel Shavings
Electrode Mass
                    47.2
                    27. <4
                    24.5
                  _ 0^9
                  100.0
                                    	Output	
Alloy
Volatilized
41.8
58.2
                                                100.0
The charge materials  for  the  production  of  silicon  metal  snould  contain
no  iron.   Petroleum coke  or  charcoal is used  as the reducing agent and
pre-baked carbon   electrodes   are  generally  used.   Power  consumption
increases  with   increasing silicon content of  the  product rrom  50* FeSi
to silicon metal.

Ferrosilicon is usually smelted  in  3-phase  electric furnaces  which  may
be  rated at over 40  mw.  Modern ferrosilicon furnaces  are equipped with
continuous self-baking electrodes and  automated charging  machinery.  The
electrodes are sheet  steel  cylinders which  are  filled with the electrode
paste, made of a  mixture  of  anthracite, coke   and other  carbonaceous
substances,  and   a mixture of coal tar  and pitch used  as a binder.  The
                                   26

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electrode is consumed  during  the  furnace  reduction  process  and  is
periodically slipped into the furnace to compensate  for its consumption.

The  charge  materials  are  prepared  in  charge  ya.ras, transported by
conveyors to the proportioning floor, and distributed among tne  furnace
hoppers.   From  the  hoppers  the charge is feet into tn<= rurnace charge
holes.  During the production  of  ferrcsilicon,  the  furnace  operates
continuously  and  the  rnetal is tapped as i4: accumulates.  Six to eight
tappings per shift are made.  After tapping is finished as indicated  by
the  appearance  of flame at the. tap hole, £:lugs consisting of electrode
mass or a mixture of fire clay and coke dust are rammed in.

FERROMANGANESE PRODUCTION

Electric  furnaces  similar  to  those  used  for  the   production   of
ferrosilicon are used to produce ferromanganese.  When ferromanganese is
produced  from  its  or-s,  iron,  manganese,  silicon, priosphorous, and
sulfur are reduced and complex iron and rnanqanese carbides  are  formed.
Smelting  is  continuous  with  metal and/or slag being tapped every 2-4
hours.

Ferromanganese is produced in the electric furnace by  eitner  tne  flux
process  or  the  self-fluxing  process.   The  self-fluxing  process is
commonly used in the United  States.   In  the  flux  process,  lime  is
introduced  in the charge; MnO which forms silicates with tne silicon in
the ore and coke dust ash is displaced by calcium oxide, reducing losses
of manganese to the slag.  Phosphorous in the ore is mostly reduced  and
passes  into  the alloy.  Up to 90% of the phosphorous in tne ore can be
reduced; the reduced phosphorous partially evaporates ana  escapes  from
the furnace while 60% of the total phosphorous in the cnarge passes into
the  alloy.  Of the total sulfur introduced in the charge l/s> passes into
the alloy, 40-45% passes into the slag, and 555t escapes with the  gases.
The  normal  charge  to  produce  high-carbon ferromanganese by the flux
method is as in Table 11.  The charge-to-alloy ratio is about 4.0.

       Table 11.  HC FERROMANGANESE CHARGE MATERIALS-FLUX METHOD
                             (% by weight)
Manganese ore                64.7
Coke                         18.0
Limestone                    16.8
Electrode mass                0.5

                            TooTo
                                  27

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In the self-fluxing method  of  producing   ferromanganese,  little  or  no
lime is introduced in  the charge;  the  slag  is  subsequently  used to smelt
silicomanganese.  By this method,  60%  of  the manganese in the ore passes
into  the  alloy, 8-10% escapes, and 30-32$ passes into the slag; 70% of
the  manganese  in  the  slag   is   extracted   when  siiicomanganese   is
subsequently produced  from  the slag.

The  normal  charge  to  produce   HC   ferromanganese by the self-fluxing
method is shown in Table 12.   Of the charged materials, 30.9% pass  into
the  alloy, 29.5% pass into the slag,  and 39.6%  escapes as  gas and dust.
The gas contains 65-70* CO.

            Table 12.  HC FERROMANGANESE  CHARGE  MATERIALS -
                          SELF-FLUXING METHOD
                              (% by weight)
Manganese ore  (48% Mn)                 74.8
Lime                                    4.6
Coke                                   20.0
Electrode mass                       	0._6
                                     100.0
Medium-carbon and   low-carbon   ferromanganese   differ   from  high-carbon
ferromanganese  by  their   reduced  carbon contents and  are produced by a
special process.  Production in an  electric  furnace  is   usually  by  the
silicothermic  reduction   method.   The  charge for  MC  ferromanganese is
composed of silicomanganese, manganese ore,  and lime, as shown in  Table
13.  The charge-to-alloy ratio  is about  3.5.
                                   28

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                  Table 13.  MC FEFROMAKGANESE  CHARGE
                              (ft ty weight)
            Manganese ore                            43.6
            Lime                                     24.3
            Silicomar.ganese  (20* Si, 65?  Mn)         31.2
            Electrode Mass                            0.9
                                                    100.0
A  similar  charge would be used to produce  LC  ferromanganese,  but using
silicomanganese  with   a   higher   silicon,    lower    carbon    content
(ferromanganese-silicon).


SILICOMANGANESE PRODUCTION

Silicomanganese  is  also  produced  in  electric submergea-arc  rurnaces.
The charge is continuously leaded and  slag and  metal are tapped 3  to  4
times  during  an  8-hour  shirt.   Siliccmangariese  may jjt  smelted from
manganese ore, from self-fluxing slag  from, ferrcnianganese production, or
from a combination of both.

A typical charge to produce silicomanganese  is  shown in Taule 14.

              Table 14.  SILICOMANGANESE CHARGE MATERIALS
                              (% by weight)
Manganese Slag
Manganese Ore
Coal or Coke
Lime
Recycle Scrap
                                  29

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Low-phosphorous silicomanganese is produced in a manner similar to  that
above except that no manganese ore is used in the charge, only manganese
slag.

FERROCHROMIUM PRODUCTION

Ferrochromium  is  produced  in several grades differing mainly in carbon
content.  Careful selection  of chrome ores  is  important  in  producing
each of the several grades of alloy.

HC Ferrochromium Smelting

In  the  production  of  HC  ferrochrcmium, the chromium ana iron oxides
contained in the ore are reduced by a carbonaceous reducing  agent.   HC
ferrochromium  is  smelted continuously; the charge materials are fed in
small portions, keeping the  furnace full while metal and slag are tapped
about every 1 1/2 - 2  hours.   Smelting  of  HC  FeCr  requires  higher
voltages  and  higher power  leadings than are used for most otner ferro-
alloys.

A typical charge for the production of HC ferrochromium, normally 60-68%
chromium, is shown in Table  15.  The charge-to-alloy ratio is about 4.0.


            Table 15.  CHARGE MATERIALS FOR HC FERROCHROMIUM
                              (% by weight)
Chromium ore                    72.4
Coke                            14.7
Quartzite                        6.6
Bauxite flux                     5.5
Electrode mass                 	0_.8
                               100.0
The charge elements pass  into  the smelting products as shown
in Table 16.
                                   30

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      Table 16.  RAW MATERIAL COMPONENTS TO SMELTING PRODUCTS FOR
                                KC FeCr
                                   in total charge	
	Element

Chromium
Iron
Silicon
Phosphorous
Sulfur
to





alloy
90
98
15
60
10
to slacj
6
2
60
20
30
loss
4
-
5
20
60
Ferrochromesilicon Smelting

Ferrochromesilicon is generally produced by the direct metnod.   In  the
direct  method,  chromium  ore  and  quartzite are reduced by coke.  The
process is carried out in arc furnaces similar  to  those  used  in  the
production of ferrosilicon.


EXOTHERMIC PROCESSES

The  exothermic  process  using silicon or aluminum, or a combination of
the two, is used to a lesser extent than the submerged-arc process.   In
the  exothermic  process the silicon or aluminum combines with oxygen of
the charge, generating considerable heat and  creating  temperatures  of
several thousand degrees in the reaction vessel.  Ihe exothermic process
is  generally  used  to  produce  higher  grade  alloys  with low carbon
content.  Low-carbon and medium-carbon ferrochromium arid  iow-carbon  or
medium-carbon  ferromanganese are produced by silicon reduction.  A flow
diagram of a typical silicon  reduction  process  for  manufacturing  LC
ferrochromium  is  shown  in Figure U,  First, chromium ore and lime are
fused together in a furnace to form a chromium ore/lime melt.  Second, a
known amount of the melt  is  poured  into  the  No.  1  reaction  ladle
followed  by  a  known  quantity  of an intermediate molten ferrochrome-
silicon previously produced in a No. 2 ladle.  The reaction in the No. 1
ladle is a rapid  reduction  of  the  chrome  from  its  oxide  and  the
formation of LC ferrochromium and a calcium silicate slag.
                                  31

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           FLOW
          Figure  A.
     SHEET  LC  FERROCHROMIUM
              ELECTRODES
Cr
ORE
                                    ELECTRODES!
COKE

WOOD
CHIPS
               FeCrSi
           SUBMERGED-ARC
               FURNACE
                 REACTION LADLE
                                 Cr ORE/LIME WELT
                                     OPEN-ARC
                                     FURNACE
                                  REACTION LADLE #1
THROW-AWAY
   SLAG
SECONDARY
THROW AWAY
   SLAG
PRODUCT
LC FeCr
t 70%Cr
                           32

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Since  the  slag  from  ladle  No. 1 still contains recoverable chromium
oxide, a second silicon reduction is made in the No. 2 laaie with molten
ferrochromesilicon  directly  from  the  submerged-arc   furnace.    The
reaction  in  the  No.  2  ladle  produces the intermediate ferrochrome-
silicon used in the No. 1 ladle reaction.  1C and MC ferromanganese  are
produced  by  a similar practice usir.g a silicon bearing manganese alloy
for reduction.

The reaction in these ladles from the silicon  reduction  results  in  a
strong  agitation  of  the  molten  bath and a rise in temperature.  The
elevated temperature and agitation produces  emissions  for  about  five
minutes per heat that have similar characteristics to tht emissions from
submerged-arc furnaces.

ALUMINUM REDUCTION

Aluminum  reduction  is  used  to produce chromium metal, rerrotitanium,
ferrovanadium and ferrocolumbium.  Although aluminum is a more expensive
reductant than  carbon  or  silicon,  the  products  are  purer.   Mixed
aluminothermal-silicothermal  processing  is  used for trie production of
ferromolybdenum and ferrotungsten.  Usually such alloys are produced  by
exothermic  reactions  initiated  by an external heat source ana carried
out  in  open  vessels.   The  high-temperature  reaction  or   aluminum
reduction  produces  emissions  for  a  limited time similar to those by
silicon reduction.

SLAG PROCESSING

Some of the electric-arc smelting processes produce slag along with  the
ferroalloy product.  These are:

     Low-carbon Ferrochromesilicon
     High-carbon Ferrochromium
     High-carbon Ferromanganese
     Silicomanganese

These  slags  may contain metal entrapped in the slag wnicn is recovered
by crushing and separation of the slag and metal  by  a  wet  sink-float
process,  called  slag concentration.  The slag fines are also separated
from the heavier particles so that a secondary product is slag  of  such
size  that  it  is  usable for road building and similar purposes.  This
process is usually  applied  to  ferrochromium  slags  for  recovery  of
chromium which is re-charged to the furnace.

Another  method  of  recovering  metal  values from manganese slag is to
"shot" the slag, then use the slag as the raw material for  electrolytic
production  of the metal.  Rapid quenching of the molten slag in a large
volume of flowing water produces a small-sized particle  (shot) wnich can
be readily leached with acid to produce  the  electrolyte  solution  for
electrolytic manganese production.


                                  33

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VACUUM AND INDUCTION FURNACE PROCESSES

The  vacuum furnace process  for producing LC ferrochromium was developed
commercially in the early  1950's.   In this  method,  carbon  is  removed
from  HC ferrochromium  in  a  solid  state within vacuum furnaces carefully
controlled at a temperature  near the melting point of the alloy.  Such a
furnace is shown in Figure 5.

The process is based on the  oxidation of HC f errochromium Dy tne  oxygen
in  silica or chrome oxide,  with which it has been mixed after crushing.
The CO gas resulting from  the reaction is pumped out ox tne  rurnace  in
order  to  maintain  a  high vacuum and to facilitate tne ferrochromium
decarburization.  Heat  is  supplied  to the furnace by electric resistance
elements.

Induction furnaces, either low-trequency or high-frequency, are used  to
produce  small  tonnages   of a few  specialty alloys throuyn remelting of
the required constituents.   Such a  furr.ace is shown in Figure 6.

PRODUCT SIZING AND HANDLING

Ferroalloys are marketed in  a bread rang^ of sizes from pieces  weighing
34. 1  kg  (75 Ibs.) to  granules of  100 mesh or finer, depending upon the
final usage.  Ferroalloys  are intermediate  products,  and  are  usually
melted  and  blended with  molten metal.  For this reason, tne rerroalloy
product size is important.

Molten ferroalloys from the  submerged-arc furr.aces are generally  tapped
into  refractory-lined  ladles and  then into melds or cnills for cooling.
The chills are low, flat iron or steel pans  that  remove  neat  rapidly
from  the  molten  pour.   After the ferroalloy has cooled to a workable
temperature,it is cleaned  of any   adhering  slag  and  sized  to  market
specifications.

The  sizing  operation  consists of breaking the large initial chills by
drop weights or hammers, then crushing and screening tne broken product.
Large jaw crushers, rolls, mills,  or grinders for reducing  tne  product
size  and  rotating  and   vibrating screens  are used ror this purpose.
Conveyors and elevators move the  product  between  the  crushing  and
screening operations.   Storage bins are provided to hola the finished or
intermediate products.
                                   34

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                                             Figure  5.

                               VACUUM  FURNACE  FOR FERROALLOY  PRODUCTION
u>
171
             TO INERT
           GAS COOLING
        REMOVABLE
        END CLOSURE
                                            TO VACUUM
                                            PUMPING SYSTEM
ELECTRICAL
LEADS
                                  CARBON
                                  RESISTORS
i

ftr TIT TT TTT
/ / A / C J\S / / Y / 'IT / / f / / Y / / / / /*./// / /


                                 n
-TRACK
                                             I I
                            Q    LL   Cl \  U   U
                                                  i
          -HEARTH
           CAR
FURNACE
CHARGE
                                                    *

-------
                                            Figure 6.

                                    INDUCTION  FURNACE DIAGRAM
t. LADLE
                                   FURNACE
      FURNACE
      CRUCIBLE
Ul
                                                            OPERATORS PANEL
                                                           ELECTRICAL LEADS
                                                                  F-LbCTklCAL  SUBSTATION

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EMISSIONS FROM SUBMERGED-ARC FURNACES

Since  the  quantity  and  composition  of the emissions rrom rerroalloy
furnaces have a major impact upon the potential for water  pollution  in
those plants using wet air pollution control devices, some discussion of
such  emissions  is appropriate.  The conventional subirieigeci-arc furnace
utilizes  carbon  reduction  of  metallics  in  the  oxiae   ores,   and
continuously  produces large quantities ot hot carbon monoxide which can
be greater by weight than the metallic product.  The CO gas venting from
the top of the furnace carries fume from high-temperature regions of the
furnace and entrains the finer sizea constituents of the mix.

In an open furnace, all CO and otht-r con^oustibles  in  the  iurnace  gas
burn  with  induced  air  at the top of the charge, resulting in a large
volume of high-temperature gas.  In a covered furnace, most  or  all  of
the   CO  and  other  gases  are  withdrawn  from  the  furnace  without
combustion.

Properties and quantities of emitted particulates depend upon the  alloy
being  produced.   Except for ejected mix particles from tne furnace the
fume size is generally below two microns (u) and ranges trom 0.1 to 1.Ou
with a geometric mean of  0.3  to  0.6  depending  upon  tne  ferroalloy
produced.   In  some  cases, agglomeration does occur, and tne effective
particle size may be larger.  Grain loadings and flowrates are dependent
upon the type of furnace and hooding.  Open submerged-arc furnaces  have
high  flowrates and moderate grain loadings, while covered furnaces have
moderate flowrates and generally high grain loadings.  In trie dry state,
the collected emissions are very light and the bulk density varies  from
64.1 to 480.6 kgs./cu. meter (4 to 30 pounds per cubic foot).

Silicon  alloys  produce  a  gray  fume  containing a high percentage of
primarily amorphous silicon dioxide  (SiO2|)   (Kef.  5).   Some  tars  and
carbon  are  present  arising from the coal, coke, or wood chips used in
the charge.   Ferrochrome-silicon  furnaces  produce  an  Sio^  emission
similar  to  a  ferrosilicon  operation  with  some  additional chromium
oxides.  Manganese operations produce a brown emission,  which  analyses
indicate  to  be  largely  a  mixture of SiC^ and manganese oxides.  The
emissions from chromium furnaces contain SiO^r MgO  and  some  iron  and
chromium oxides.

Chemical  analysis of the fumes indicate their composition to be similar
to oxides of the product being produced.  Typical chemical analyses  are
given in Table 17.
                                  37

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                                     Table 17.  TYPICAL FURNACE FUME CHARACTERISTICS
CO

Furnace product
Furnace type
Fume shape


Fume size char-
acteristics ,
microns
Maximum
Most particles
X-ray diffraction

trace constituents



Chemical
Analysis, %
Si02
FeO
MgO
CaO
MnO
A1203
LOI
TCr as C^Oj
SiC
Zr02
PbO
Na20
BaO
K20
50% FeSi SMZ a
Open Open
Spherical, Spherical
sometimes sometimes
in chains in chains



0.75 0.8
0.05 to 0.3 0.05 to 0

All
FeSi Fe304
FeSi2 Fe203
Quartz
SiC


63 to 883 61.12
14.08
1.08
1.01
6.12
2.10
-
-
1.82
1.26
-
-
-
—
SiMnb
Covered
, Spherical





0.75
.3 0.2 to 0.4

fumes were- prf
Mn304
MnO
Quartz



15.68
6.75
1.12
-
31.35
5.55
23.25
-
-
-
• 0.47
_
-
—
SiMnb
Covered
Spherical





0.75
0.2 to 0.4

FeMn
Open
Spherical





0.75
0.05 to 0.4

• HC FeCr
Covered
Spherical





1.0
0.1 to 0.4

Chrome ore
lime melt
Open
Spherical
and
irregular



0.50
0.05 to 0.2

- Mn ore-
lime melt
Open
Spherical
and
irregular



2.0
0.2 to 0.5

.marily amorphous
Quartz
SiMn
Spinel



24.60
4.60
3.78
1.58
31.92
4.48
12.04
-
-
-
-
2.12
-
—
Mn304
MnO -
Quartz



25.48
5.96
1.03
2.24
33.60
8.38
-
-
-
-
-
-
-
—
Spinel
Quartz




20.96
10.92
15.41
-
2.84
7.12
-
29.27
-
-
-
_
-
—
Spinel





10.86
7.48
7.43
15.06
-
4.88
13.86
14.69
-
-
-
1.70
-
—
CaO





3.28
1.22
0.96
34.24
12.34
1.36
11.92
-
-
-
0.98
2.05
1.13
13.08
    Si - 60 to 65%; Mn - 5  to  7%; Zr - 5  to  7%
    3
    Manganese fume analyses in particular are subject  to
      wide variations, depending on the ores used.

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EMISSIONS FROM EXOTHERMIC PROCESSES

Oxide  fumes  similar  in  physical  characteristics  to  -cnose from the
submerged-arc furnace are emitted from the  reaction  ladle  or  rurnace
while   the   reducing   agent  is  being  charged  during  alumino-  or
silicothermic reduction.  This emission is du<; to  strong  agitation  of
the  molten  bath and the rapid temperature: rift-.  The reaction may take
from 5-15 minutes per heat, and the heat cycle  is  about  1  1/2  to  2
hours.   Therefore,  atmospheric emissions fron. the exothermic reactions
take place during about 10 percent of the cycle.

The quantity of emissions from the exothermic reactions ranges from 9.08
to 18.6 kg (20-UO Ibs)  of particulars \..*-.r ton of ferroalloys  produced.
The  total tonnage of ferroalloys rnadt by the exothermic process amounts
to 10 to 15 percent of the total ferroalloys production  in  the  United
States.

OPERATING VARIABLES AFFECTING EMISSION'S

Because  of  the  complexity  of  the  heavy  mechanical  and electrical
equipment  associated  with  a  modern  submerged-arc   lurnace,   close
supervision  and  maintenance  are  required to prevent frequent lurnace
shutdowns.   The  furnaces  are  designed  t.o  operate  continuously  to
maintain satisfactory metallurgical and thermal equilibria.

Normal  furnace  shutdowns  on  an annual basis may average tnree to ten
percent of the operating time and  are  caused  by  a  wiae  variety  of
situations.   These  can be electrode installations, maintenance, repair
of water leaks at electrode contact plates, mix cnute taiiures,  furnace
hood  or  cover  failures, taphole problems, eif-cr.ricai or other utility
failures, crane failures, ladle or chill  problems  or  curtailments  of
service  by  the power companies.  In general, furnace interruptions are
relatively short i'n duration and  usually  are  not  more  than  several
hours.   Following  such  interruptions,  the turnace usually returns to
normal operation with normal emissions in a period of time approximately
equal to the length of the interruption.

Greater-than-normal emissions occur after returning power to the furnace
following a lengthy interruption caused by & major  furnace  operational
problem.   These  problems  may  include electrode failure that makes it
necessary to dig out an electrode stub or to bake at a reduced load  for
self-baking  electrodes, serious mixture blows of the turnace, metallur-
gical problems that require a furnace burndown to return  it  to  normal
operations,  serious  water  leaks  that  flood  the furnace with water,
furnace hearth failure, major taphole  problems,  transformer  or  major
electrical  system failures, etc.  When starting up a new turriace or one
with a cleaned out hearth, as well as a furnace with a cold hearth after
a long shutdown, heavier-than-normal emissions may last  up  to  a  week
before the furnace operates in an optimum manner.
                                  39

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The  quantity  of  emissions  from  submerged-arc  furnaces will vary up to
several times the normal emission  level over a period  of  one  ro  three
percent of the operating time due  to major  furnace  interruptions and, to
a lesser extent, because of normal interruptions.

QUANTITIES OF EMISSIONS

Emissions  and emission rates will vary with  (1) type  of alloy produced,
(2) process  (i.e., continuous or batch),  (3) choice of raw materials and
pretreatment thereof,  (1) operating techniques,  (5)  furnace  size,   (6)
maintenance practices.

An example of the varying emissions that  result  from process changes can
be  seen  in  the manufacturing of silicon  alloys.  As the percentage of
silicon in the alloy increases, the loss  of Sic^ increases, therefore,  a
silicon-metal furnace  emits   substantially more   SiO2  fumes  than  an
equivalent-size 50 Jt f errosi li con furnace.

Emissions from batch-operated open-arc  furnaces  are periodic.  Following
sudden  addition  of   mix   containing   volatile  or  reactive constituents
(coal, moisture, aluminum,  etc.) to a her furnace crucible, violent  gas
eruptions can occur.   This  is best exemplified by the  manganese ore-lime
melt furnace where momentary  gas £ low following  mix addition can be five
times  the  average  flow.    Under  these  conditions, temperature, dust
loading, and gas flow  all peak simultaneously.   In  contrast,  chromium
ore-lime  melt  furnaces,   to which few or  no gas-releasing constituents
are fed, are not subject to this violent  behavior.

Some of the special alloys  are also produced by  aluminothermic reactions
without the addition of electrical energy.  These reactions  also  cause
momentary peaks of gas flow with high emission rates.

Volatile materials in  the furnace  charge  may cause  rough operation.  One
significant  contributor  to   such  operation  is the  presence of fines,
moisture or  dense  material   in   the   feed.   These   materials  promote
bridging  and  nonuniform   descent  of  the charge  which may cause gas
channels to develop.   The collapse of a bridge, causes  a momentary  burst
of  gases.   A  porous charge will promote uniform gas distribution and
decrease bridging.  For some  products economics  dictates the use of  raw
materials  with  more  fines or with more  volatile matter than desirable.
Pretreatment of the feed materials promotes smooth  furnace  operation.
Each  of  these  factors  has an  effect on the smootn operation of the
furnace, and consequently upon the emissions.

Differences in operation techniques can have  a  significant  effect  on
emissions.   The  average   rate  of  furnace  gas production is directly
proportional to electrical  input,  so that  a  higher   load  on  a  given
furnace  normally  causes a proportional  increase in emissions.  In some
cases, emissions increase at  a rate greater than the load increase,  due
to rough operation and inadequate  gas withdrawal.


                                   40

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At  a  fixed load and with the gas geirrration remaining  almost  constant,
the emission concentration and weight per hour of particuiat.es  can   vary
by  a factor of 5 to 1.  Operating with insufficient electrode  immersion
promotes increased emissions.

Higher voltage  operation  tor  a  given  furnace  wilx  promote  higher
electrode  positions  and  increase  tht-  concentration  ana  amount  of
emissions.

On some operations, especially silicon rr;ital production, the  cnarge  must
be stoked to break up crusts, cover areas of gas blows,  ana   permit   the
flow .  of  reaction  qases.   Therefore,  both  furnace  operations   and
emissions can be a function of hew well and hew  oiter   the   rurnace  is
stoked.

Maintenance practices significantly affect emissions en  coverea furnaces
because  accumulation  of  material  under  the  cover   ana in  gas ducts
reduces the gas withdrawal capacity of the exhaust system.  Plugging  of
gas  passages  in the control equipment results in reduced etticiency of
gas cleaning.

PRODUCTION AND EMISSION DATA FOR FERROALLOY fURNACES

The data in Table 18 summarize  pertinent  data  as  to  production   and
emission factors for submerged-arc furnaces  (Fief. 32) .

The  data  of  Table  19  summarize  the  types of air pollution  control
devices used in various ferroalloy furr.dces producing specific  products
in the United States.

Some  comparisons  of  the  off-gas  volume  from  coverea  lurnaces and
controlled open furnaces are shown in Table 20.

Table 20.  ILLUSTRATIVE OFF-GAS VOLUMES FROM OPEN
           AND CLOSED FURNACES - REF 32.
Product
FeMn
FeSi (65-75%)
SiMn
FeSi (50%)
                      Closed Furnaces
                   m./llm.w.
                     6.16
                     5.88
                     5.60
                     5.04
                                          Open Furnaces
                                                       scrm/mw
220
210
200
180
370
521
204
258
13,200
18,600
7,300
9,200

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                              Table  18.   PRODUCTION AND EMISSION DATA FOR FERROALLOY FURNACES
NJ

Uncontrolled Participate Emissions
Product
Si 1 very
Iron
50 % FeSi
65-75% FeSi
Si Metal
SMZ
Mn ore/1
CaSi
HCFeMn
SiMn
FeMnSI
FeCrSi
Chg Cr
HCFeCr
Cr ore/1


ime melt







ime melt
kg/kkg alloy Ibs/ton alloy kg/mwhr Ib/mwhr
58
223
458
500-1000
No data
67
672
168
110
158
416
168
168
6
116
446
915
1000-2000
No data
133
1343
335
219
315
831
335
335
11
20.4
40.4
47.2
33-65
No data
37.7
51.7
28.1
22.7
26.3
50.8
28. T
28.1
4.1
45
89
104
72-144
No data
83
114
62
50
58
112
62
62
9
Electric Energy
mwhr/kkg alloy mwhr/ton alloy
2
5
9
15
9
1
13
2
4
6
8
4
4
1
.9
.5
.7
.4
.7
.8
.0
.6
.9
.0
.2
.6
.6
.3
2
5
8
T4
8
1
11
2
4
5
7
4
4
1
.6
.0
.8
.0
.8
.6
.8
.4
.4
.4
.4
.2
.2
.2
Ratio of
Charge
to Product Weight
1
2
4
4
4
3
3
3
3
4
3
4
4
1
.8
.5
.5
.9
.5
.5
.9
.0
.1
.3
.4
.0
.0
.2

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    Table 19.  TYPES OF AIR POLLUTION CONTROL SYSTEMS USED ON AMERICAN FERROALLOY FURNACES
    Covered furnaces with withdrawal and
      cleaning of unburned gases
                               Open furnaces with withdrawal and
                                 cleaning of burned gases
    Control device
    Wet scrubbers
U)
     Products

Ferromanganese
50 to 75% Ferrosilicon

HC ferrochromium
Silicomanganese
Control device
Wet scrubbers
                                                      Cloth type
                                                        filters
                                                      Electrostatic
                                                       precipitator
       Products

50 to 85% Ferrosilicon
Silicomanganese
HC ferrochromium
Ferrochrome-silicon
Silicomanganese
Ferromanganese silicon
75% and higher grades
 of ferrosilicon
Silicon metal
Ferrochromesilicon
HC ferrochromium
Ferrochromesilicon

-------
                               SECTION  IV

                        INDUSTRY CATEGORIZATION

The purpose of the effluent limitation  guidelines  car. be  realized  only
by categorizing the industry into the minimum number 01  groups ror which
separate  effluent  limitation  guidelines   and  new sources performance
standards must be developed.  The categorization here is £>eiievea -co  be
that  minimum,  i.e.,  the  least  numt.er of uroups  having sigiiiricantiy
different water pollution potentials ar.c treatment prcolerris.

I.    Open Electric Furnaces with Wet Air £-cllu~ior.  Control
      Devices
II.   Covered Electric Furnaces and Other Smelting
      Operations with Wet Air Pollution Ccr.rrcl Devices
III.  Slag Processing
IV.   Noncontact Cooling Water

In developing the above  categorization,  the   following  raccors  were
considered  as  possibly providing some has is  for  categorization.  These
factors include characteristics of individual  plants, various production
processes, and water uses.

1.  Air Pollution Control Equipment

2.  Production Processes

    a. Electric Furnace

    b. Exothermic

    c. Slag Processing

3.  Furnace Types

    a. Open

    b. Covered or Sealed

H.  Raw Materials

5.  Product Produced

6.  Size and Age of Production Facilities  .

7.  Waste Water Constituents

8.  Treatability of Wastes

9.  Water Uses

-------
    a. Wet Air Pollution Control Devices

    b. Cooling Water

    c. Electric Power Generation

    d. Sanitary Wastes

    e. Slag Processing

    f. Drainage From Slag  or  Raw Material storage

Air Ppllutign_Control^Eguipmenr

Air pollution is the major pollution problem in this industry.  Much  of
the water pollution problem is created by solving air pollution problems
with  wet  air  pollution   control devices suet: as scrubbers.  Since the
only water pollution potential from an electric furnace, whicn is either
uncontrolled or controlled with a dry air pollution control  system  (such
as a baghouse), is that from  cooling water there is no justification for
including these furnaces   with  those  having  wet  systems,  since  any
standard which would be fair  to the 'wet1 furnaces, would &e excessively
permissive  to  the  'dry1  ones,  and vice versa.  For tnis reason, the
categorization  selected   is  partially  based  upon  trie  type  of  air
pollution control equipment,  i.e., wet or dry.

Although another breakdown might be made based upon the types of wet air
pollution   control   equipment,   such   as   high   energy  scrubbers,
disintegrator scrubbers, electrostatic precipitat.ors with water  sprays,
etc.,  this  would  unnecessarily  multiply the number of categories and
have too small an  effect   upon  the  total  pollutant  load  from  this
industry to be warranted.

It  should be noted that a 'wet' furnace will receive two allowances for
water pollution, one from  either Category I or  II  depending  upon  the
type of furnace, and also  from Category IV for noncontact cooling water.
A  'dry1  furnace, however, will receive an allowance only from Category
IV.

Production Processes

The various production processes  vary  markedly  in  their  anility  to
pollute water, and this provides an additional basis for categorization.
This  basis  consists  of   the  differential  in  raw  waste  loads  and
concentrations between the slag processing operations and  the  electric
furnace  and  exothermic processes.  The electric furnace and exothermic
processes are dry by nature,  although water  is  used  for   cooling  and
possibly for air pollution abatement.  The plant survey data obtained at
an exothermic operation using wet air pollution control methods indicate
that  the water use per ton is of the same order of magnitude as that of


                                  46

-------
covered electric furnaces, and the exothermic operations were  -therefore
included with the covered electric furnaces.

Although  not  properly a ferroalloy production process, slag processing
is performed at many plants to recover r.he residual metal values left in
the slag after smelting, and helps reduce -he solid waste load  somewhat
at these plants.  This process is intrinsically different from the other
production  processes, inasmuch as it is inherently 'wet', ana tnerefore
merits  a  separate  category.   Additionally,  the    'building   block'
approach, such as is used for establishing the allowable plant effluents
herein,  requires a separate category since all plants do not use such a
process and the magnitude of the potential wasteload is substantial.

Furnace TyjDes

The types of smelting  furnaces  were  found  to  provj.ce  a  basis  for
categorization in conjunction with consideration oi water uses and other
factors.   The  differences  between oj_en and covered  or sealed electric
smelting furnaces are significant insofar as  they  relate  to  trie  raw
waste  loads  and  the  pollutants  present  and  air  pollution control
technologies available for use.  The olf-gas volumes from tne two  types
of  furnaces  may  vary  by  a  factor  of  50  between tne two types of
furnaces, and cyanides are present, in scrubber waters  from  the  covered
types, but not from the open type.  The water uses for wet air pollution
control  devices  may  be  quite different due to tne  aifrerences in the
off-gas volumes.  Person's (5) published aata shew a difference in water
circulation with venturi scrubbers of a factor of 2<4   between  open  and
covered  furnaces.  The final volume ot water flowing  from the scrubbers
on open or covered furnaces may not vary significantly; the plant, survey
data indicate, in fact, that the  differences  are  not  great  and  are
probably  more  dependent  on  scrubber  type  thcxn  furnace  type.  The
recirculation of water at the venturi scrubbers on open xurnaces must be
regarded as a part of the  waste  wa-^er  treatment  metnods  and  is  so
specified when effluent limitations for such sources are determined.

Additionally,  dry dust collectors are widely used on  open furnaces, and
are more common than wet collectors.  The converse is  true with  covered
furnaces.   There  are  only  two  kncwn examples of dry dust collectors
being installed on covered or sealed furnaces, while the  vast  majority
utilize wet air pollution controls.

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Raw Materials

Depending  on  the  product  produced, the raw materials  for the  smelting
operations vary principally  in  the types of ores and the proportions  of
the   materials   in  the  charge.   For  example,  the  cnarge  for  HC
ferromanganese consists  of manganese ore, coke, and limestone, wnile the
charge for HC ferrochromium  consists of chromium  ore,   coke,  quartzite
and  bauxite  flux.   There   are  no  differences,  however,  in the raw
materials used in the production of  50?;  ferrosilicon,  whether  it  is
produced  in  an  open   or covered furnace, although trie coverea furnace
feed  materials  may  require  pretreatment.   There  are,  of   course,
substantial  differences  in the  charge into electric  furnaces and the
feed to slag processing  operations.


Pr o du ct _ Pro duced

Categorization by product would result in a large number of  guidelines
and  standards,  since the number of products which can  ue produced in a
furnace is fairly large, and many products car  be  produced  in  either
open  or  covered  furnaces.    Additionally,  this  method  would  create
unnecessary problems for the person writing the discharge permit,  since
plants  are  accustomed  to changing the product produced in the  furnaces
depending upon market conditions.  For  example,  during the  last  few
years, with a decline in the market for ferrochromium and ferromanganese
products,  many  plants  discontinued cr cut back the production  of these
products and converted to other, more profitable oroduct lines.  With  a
categorization  based  on product, this would either entail the  issuance
of a new discharge permit, or the writing  of  the  original  permit  to
reflect all the possible variations which may take place.

Size and Age of Facilities

The  size  and  age  of  production  facilities  provides  no  basis for
categorization.  This judgement is based largely upon the fact that  the
emissions  factors  for  the various products  (given in  kg  (Ib)/rnwhr and
which represent the uncontrolled particulate emissions   and  upon  which
the  raw  waste  water   loads are dependent) are not variable by furnace
size.  Since effluent loads  were based upon units of electric power used
in the furnaces, the factor  of  furnace size seems to  oe eliminated  by
the  nature  of the process.  Size of the plant may have some bearing on
the cost of waste water  treatment, since obviously it will cost  a very
small  plant  more for treatment per unit capacity than  it would a large
one, but this is not so  great as to warrant categorization.

Although the older furnaces  are not as likely to be controlled   for  air
emissions,  and  therefore   to  require scrubber water treatment,  by the
nature of the categorization selected this has been taken into   account.
The newer electric furnaces  differ from the older ones only in size; the
older  furnaces  are  about   10 mw or less, the newer ones are double or

-------
triple that in size.  The essential nature cf the  furnace  has  changed
little  over  many  years,  although newer furnaces may utilize somewhat
more water for cooling.

Was te_Water Constituents

The waste water constituents provide a collateral, but  not  independent
basis  for  categorization.   Suspended  solids  are  tne largest single
constituent of -che waste waters and appear in effluent from ail  of  the
various  processes.   Suspended  solids obviously result from the use of
wet devices to remove particulates from smelting  off-gases.   Cnromium,
as   another
operations,
recirculated
inhibitors.
in  covered
between open
              example,  is  in  the  effluents  from  cnromium  smelting
              chromium   slag   concentrating   operations,   ana   from
              cooling  waters  when  chromates  are  auaea  as corrosion
             Cyanides are generated in significant  concentrations  only
             furnaces.   This distinction appears in tne airf erentiation
             and closed furnaces and is thus no  independent  basis  for
categorization based on waste water constituents.

Treatability^of Wastes

Treatability  of  waste  also provides a collateral, but not independent
basis for categorization, largely for the same reasons  tnat  the  waste
constituents   do.    The   treatment  methods  consist  principally  of
coagulation  and  sedimentation,   neutralization   ana   precipitation,
reduction   of   chromium,   oxidation   of  cyanides  and  phenol,  and
recirculation and re-use.  All of  these  methods,  except  tor  cyanide
oxidation, are applicable to one extent, or another in all of tne various
types of production operations.  Cyanide is found in scrubber water only
from  covered  furnaces,  but  such a differentiation is inherent in the
chosen categorization, since covered furnaces are separately  considered
for other reasons.

From  the  standpoint  of  air  pollution  control,  emissions from open
electric furnaces  are  fairly  easily  controlled  wita  fabric  filter
systems, and this method has been commonly used in the inaustry tor this
type  furnace.  Covered or sealed furnaces, however, in this country are
uniformly controlled with wet scrubbers, although there are two  foreign
plants  which  utilize  dry  dust  collection  systems  for  control  of
emissions from covered furnaces.

The use of baghouses, of course, reduces water use to  zero  insofar  as
air  pollution  controls  are  concerned, and a smelting furnace shop so
equipped does not fall under the categories  based  upon  furnace  type,
only the category for cooling water.

Water Uses

Water  uses  were  judged  to be a significant basis for categorization.
The categorization differentiates between  processes  on  the  basis  on
                                  49

-------
water use for wet air  pollution control devices, for slag processing and
for   noncontact  cooling.    Cooling  water  is  used  in  all  smelting
operations and should  be a  function  of  power  input  to  the  furnace.
Cooling water can be handled  in different ways that significantly affect
effluent heat loads and flow  volumes.  Cooling system effluents can also
be used as scrubber water makeup.  The use of different systems requires
that  cooling water be separately  categorized so that a "building block"
approach can be used in determining allowable plant effluents.

Electric power is presently generated in very few ferroalloy plants.   A
separate  category is  not. warranted; the guidelines separately developed
for steam electric power plants should be applicable, since, as shown in
the previous section,  water use per kwnr is about the same as for  power
plants  in  general.   Sanitary wastes are common to all plants, whether
treated on-site or discharged to a  municipal  treatment  plant  and  no
separate category is needed.
                                   50

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                               SECTION V

                        WASTE CHARACTERIZATION

The  waste  characteristics  to  be  determined may  be  considered on  the
basis of the industry categories and the various water  uses  ab  follows:

1.  Cooling Water - Electric Furnace Smelting
2.  Water for Wet Air Pollution Control Devices
    a.  Electric Furnace Smelting
        i.    Disintegrator-type Scrubbers
        ii.   High Energy Scrubbers
        iii.  Electrostatic Precipitator Spray Towers
        iv.   Steam/Hot Water Scrubbers
    b.  Exothermic Smelting Processes
3.  Sanitary Uses, Boiler Feed, Air Conditioning,  etc.
4.  Slag Processing Uses

PUBLISHED DATA SOURCE CHARACTERIZATIONS

A total of 2,329,630 kxgs (2,568,500 tens) of ferroalloys  were   produced
in  1967,  using  11,206 million kw-hrs. of  electric energy  according to
the ,1967 Census of Manufactures Of rht total energy  used,  J,354  million
kw-hrs.   were  generated  by  ferroalloy plants.  Assuming miscellaneous
losses and other uses of 15 percent, an average use  of  4,Ub9 x.w-nrs.  per
kkg (3,709 kw-hrs. per ton  of  alloy  in  terms   of  rurnace  power   is
indicated.

Total water intake for S.I.C. 3313 plants was 1128.7 X  109 liters (298.2
X 109 gals.) per year according to the 196_7_Cen.s_us_cf_Manu£.aCturfc3 while
gross water use was 1212.3 X 10* liters  (320.3 x 109 gals.).   Intake  for
cooling  was  381.5 X 109 liters (IOC.8 X 109 gals.).   Assuming that  all
water recirculation and reuse was for cooling,  cooling water   use  was
465.2  X  109  liters  (122.9 X 109 gals.)   Cooling  water  use of 199,679
liters per kkg (47,849 gal. per short ton)   of  alloy,   or   4a.8  liters
(12.9 gals.) per kw-hrs. of furnace power is indicated.

The  J_96_7 _Cens_us _of_	Manufactures indicates a water  use  of  701.4 X  109
liters (185.3 X 109 gals.) of water  in  generating  tne  aforementioned
3,354 million kw-hrs. of electric energy in-plant.   The indicated use of
208.9 liters (55.2 gals.)  per kw-hrs. is about equal to the  1964 thermal
electric  power  plant use of 215 liters  (56.8 gals.)  per  kw-hr.  (Final
Report, EPA Contract 68-01-0196).  Assuming  losses and  otner uses at   15
percent,  a water use of 245.6 liters  (64.9  gals.) per  kw-nr.  of rurnace
power is indicated for in-plant power generation.

The 1967 census data indicate a use of 40.9  X 109  liters   (10.8  X  109
gal.)   per  year  for sanitary, boiler feed, air conditioning,  and other
minor uses and plant employment of 8,700.  At 378.5  liters   (100  gals.)
per  capita  per day, 250 days per employee  per year,  sanitary use would


                                  51

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have been 825 X  106  liters  (218  X  106  gals.)  per  year;  air   conditioning
use  was  757 X  10*  liters  (200  X  106  gals.)  per  year.  These  uses  total
4.28 liters  (1.13 gals.)  per  kw-hr.  of furnace  power,  assuming  losses
and other uses at 15  percent.
Person's  data   (5)   indicate  the water  use  in  high  energy  scrubbers  on
open furnaces as 113.6  I/sec  (1,800  gpn.)   for each   of   three   furnaces
producing  FeCrSi,   SiMn,   and   HC   FeCr   ar.d rated at  25, 30 and  30 mw,
respectively.  At  an assumed  operating  load of 75%  with   95%   operating
time,  the  indicated  water  use is  1,226,340 liters  (324,000 gals.) per
60.6 mw-hrs., or 20,238 liters   (5,347  gals.)   per   mw-hr.  of furnace
power.

Person's  data  further indicated an average  use of. 5.5 I/sec  (87.5 gpm)
for a high energy  scrubber  on a semi-closed 45 mw 50* FeSi furnace.    At
95%  operating  time and 75% operatincr load, the indicated  water  use  is
620.7 liters  (Ifa4  gals.) per  mw-hr.  of  furnace power.

According  to  Retelsdorf,  et.al.   (6)   an   electrostatic   precipitator
installed  on  a   20 mw ferrochromesilicor. furnace uses water in a spray
tower preceeding the precipitator at the   rate  of  about 9,084  liters
(2,400  gals.)  per   hour.    This indicates   a  use of  635.9 liters  (168
gals.) per mw-hr.  of furnace  power at   959? operating   time   and  75%
operating  load.   About 10-15 % of the  water  used is  discnarged from the
bottom of the spray  tower,  the  remainder  being evaporated into   the  gas
stream.  These data  indicate  about 556.4  liters  (147  qals.)  o±  water per
mw-hr. of furnace  power evaporated in the gas stream.

From  the  above   data   and  those   given  in Section  III,  some limited
calculations of waste characteristics may be  made.

Cooling water volumes for electric furnaces   would  be  expected  to   be
about  48.8  liters   (12.9  gals.)   per  kw-hr.  of furnace power.   Once-
through use would  be expected to alter  such water only  to trie extent   of
increasing temperatures above the inlet levels.   Most industrial cooling
water  systems are designed for a change  of temperature of 6.6  to  12.0°C
(10-20°F).  Recirculated cooling water  blowdown may  oe   expected   to
average  about  1-2% of the  recirculation   rate,   with 2 cycles   of
concentration, i.e.,  the blowdown will  contain twice  the   concentrations
of  constituents in  the intake  water.  Additionally,  such blowdowns will
contain chromates  or phosphates used for  corrosion  control, and   other
treatment chemicals  such as biocides, slime inhibitors, etc.


Assuming  that  556   liters  (147 gals.)  of  water per  mw-hr. of furnace
power is evaporated  in  the  ga§  streams  from open furnaces using wet  air
pollution  control   devices  and that  such   evaporation in the case  of
covered furnaces is  in   proportion   to  the   gas volume, the   effluent
volumes expected would  be as  follows:
                                   52

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High energy scrubbers (open furnace)  = 19,682 1/mw-hr  (5200 gal/mw-hr)

High energy scrubbers (covered furnace) = 609 1/mw-hr  (ibl gal/ mw-hr)

Electrostatic precipitator = 79.5 1/mw-hr (21 gal/mw-hr)

On  the  basis of the data given in Section III on production processes,
compositions of raw materials, and  compositions  of   products  and  by-
products,  the  following  constituents/parameters  appear  to  be those
potentially present in waste water:

Acidity                 Columbium          Potassium
Alkalinity              Cyanide            Padioactivity
Aluminum                Dissolved Solids   Silica
Ammonia                 Iron               Sulfates
Barium                  Magnesium          Suspended Solids
B. O. D.                Manganese          Temperature
Calcium                 Molybdenum         Titanium
Chrcmates               pH                 Vanadium
Chromium                Phosphates         Zirconium

WASTE CHARACTERIZATIONS FROM DISCHAKGh PERMIT DATA

Waste constituents/parameters listed as present, in discharge
permit applications for the plants in S.I.C. 3313 ar-  as
follow:

Algicides               Fluorides          Sodium
Aluminum                Hardness           Solids
Ammonia                 Iron               Sulfats
Barium                  Magnesium          Sulfide
Boron                   Manganese          Sulfite
Calcium                 Nickel             Surfactants
Chloride                Nitrate            Titanium
Chromium                Oil and Grease     Turbidity
Color                   Organic N          Zinc
Copper                  Phosphorous

Additionally, pH and temperature are given as waste parameters.

WASTE CHARACTERIZATIONS FROM PLANT SURVEY DATA

Waste characteristics were determined  where  possible  from  the  plant
survey  data  for various specific waste-producing sources.  These data,
of course, apply to the particular units operating as  triey  were  during
the  sampling  period  and  represent  the type of result to be expected
during the actual  operation.   To  the  extent  possible,  reasons  for
variations are explained.
                                  53

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WASTE  CHARACTERIZATION
CONTROL DEVICES
              - OPEN ELECTRIC FURNACES WITH WET AIR POLLUTION
The data from Plant D provides raw waste loads for
furnaces  in  which  the  off^gases  are  scrubbed
scrubbers as shown in Table  21.
                                         open  submerged  arc
                                         wirn steam/hot water
Table 21.
RAW WASTE LOADS-OPEK CHROMIUM ALLOY AND
FERROSILICON FURNACES WITH STEAM/HOT WATER SCRUBBERS
	Constituent
Suspended Solids
Phosphate
Phenol
Oil
CN, total
CN, free
Iron
Manganese
Zinc
Cr, total
Cr, hex.
Lead
Aluminum
Flow
kcr/mwhr
8.2
.010
.0004
.002
.0001
.00005
.069
.005
.068
.003
.002
.008
.158
Ibs/mwhr
18.1
0.023
0.001
0.004
0.0002
0.0001
0.152
0.010
0.149
0.007
0.004
0.018
0.348
                            1/mwhr
                 2, 6 SI
The data from Plant L provide  an additional raw waste load tor  an
electric furnace using a venturi scrubber, as shown in Table 22.
                                                         open
                                   54

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Table 22.  RAW WASTE LOAD - HIGH ENERGY  SCRUBBFfc
           ON OPEN ELECTRIC FURNACE
	Constituent

Suspended Solids
Phosphate
Phenol
Oil
Cyanide (Total)
Iron (Total)
Manganese
Zinc
Chromium (Total)
Lead
Aluminum
Flow
 venturi scrubber
kcj/mwhr
23.74
0
0.0005
0.006
0
0.041
1C. 06
0. 33
C.002
0. 07
1. 13
1/mwhr
6,382
Ihs/mwhr
52.29
0
0.001
0.014
0
0.089
22. 15
C.72
0.005
0.16
2.49
qals/mwhr
1 ,666
The  data  from Plant G providing  raw  waste  loads for Oj-tn submerged arc
furnaces in which  the  off-gases   are   conditioned  in  a  spray  tower
preceding an electrostatic precifitatcr  are  shown in Tai^le ^3.

Table 23.  RAW WASTE LOADS-OPEN CHROMIUM ALLOY
           FURNACES WITH ELECTROSTATIC FRECIPITATOkS
            Stituent
Suspended Solids
Phosphate
Oil
Iron
Manganese
Zinc
Chromium, total
Aluminum
Flow
   269
   00001
   0001
   001
   0012
   001
   0016
   0070
                                 1/mwhr
84.0
Ibs/mwhr

 0.636
 0.00002
 0.0002
 0.002
 0.0026
 0.003
 O.OC36
 0.0155

gals/mwhr

  22.2
                                   55

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Although  the data as  given  in Table 23  for water flow  agrees quire well
with that predicted  (84.0 vs 79.5  1/mwhr) (22.2 vs 21 gal/mwnr) , and  the
flow  rate  from  the  steam/hot water scrubbers cannot be compared with
anything, the values for flow from the high energy  scrubber  are  about
one-third  of  that  predicted.    However, the flow from the nigh energy
scrubber does not take into  account recirculation of tne scrubber  water
which  is  done  at  the  scrubber prior to clarification and which may
account for the difference.

WASTE CHARACTERIZATION-COVERED ELECTRIC  FURNACES WITH WET
AIR POLLUTION CONTROL  DEVICES


The data from Plant B  provides  information  on  the  waste  water  from
disintegrator  scrubbers operating on covered furnaces  producing silicon
alloys.  Raw waste loads of  suspended solids and cyanides are  given  in
Table  24  on the basis of the furnace power during the 16-hour sampling
periods.

Table 24.  RAW WASTE LOADS FOR COVERED FURNACES
           WITH DISINTEGRATOR SCRUBBEES
         Suspended Solids	Cyanides	Flow	
                 Ibs/mwhr  kH^mw.hir  Ibs/mwhr _l/inwhr gal/mwhr
SiMnZr    20.1
75% FeSi  39.2
50% FeSi   5.1
75% FeSi   6.8
                   44.3
                   86.3
                   11.3
                   15.0
0338   ,0745
0001
0139
.0002
.0307
8270
8967
8823
7562
2185
2369
2331
1998
The data for the second  furnace  in  Table  24  probably represent  reliable
data,  since  at 75%  particulate removal  efficiency the  suspended  solids
load is somewhat higher  than  are given  in the EPA  air   pollution  study
(Ref.  32)  data.   The   remaining   data  in Table 24 indicate  suspended
solids loads much  lower  than  would  be expected  from  tne air   emissions
data.   This  could   have either occurred due to poor functioning  of the
scrubbers  (as evidenced  by the lower temperature of the   effluent  water
and  observations  of visible   stack   emissions, sometimes  very heavy).
Another possible explanation  is  that the  samples may have ueen  taken   in
a  region  where   water   sprays  are used  to  suppress foaming, and  could,
therefore, have been  diluted.

The data from Plant   C   provides raw   waste load  data tor   a   sealed
silicomanganese  furnace  where  the off-gases  are scrubbed in a spray
tower and  a disintegrator scrubber.  These data are shown in Table 25.
                                   56

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Table 25.  RAW WASTE LOADS-SEALED SIL]
           FURNACE WITH  DISINTEGRATOR
            .CCMANGANESE
            SCFUPJ-EF
     Constituent
Suspended
Phosphate
Phenol
Oil
Cyanide,
Cyanide,
Iron
Zinc
Chromium,
Lead
Aluminum
Manganese
Flow
          solids
         total
         free
          total
kq/rnwhr-

16.6
  . 052
  .009
  .038
  .044
  .011
  . 056
  .224
  .0004
  .033
  .413
 4. 858

1/mwnr

10,863
Ibs/mwhr
 36.
                                        10
b
1 14
019
084
098
0^4
123
493
001
072
91
70
gals/rrwhr

 2,87C
The data from Plant E also  proviae data  on  scruhber  raw  Wctste   water
loads  from covered furnaces  equipped with high energy ar.a disinregrator
scrubbers.
                                   57

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Table 26.  RAW WASTE LOAD-CQVERED FURNACES  WITH
          SCRUBBERS
	Constituent

Susp. Solids
Phosphate
Phenol
Oil
Cyanide  (Total)
Iron (Total)
Manganese
Zinc
Chromium  (Total)
Lead
Aluminum
Flow
  4.01
  0.004
  0.002
  0.022
  O.OQ7
  0.08
  0.016
  0.21
  0.002
  0.023
  0.07

1/mwjjr

9,746
  Ibs/mwhr

   8.83
   0.008
   0.004
   0. 048
   0.015
   0.17
   Ol034
   0.45
   0.004
   0.051
   6.16

gals/mwhr

 2,575
The data from  Plant  H   provide   data   on   the   raw  waste  loads  from
aluminothermic  production  of  chromium  alloys  in  which  the off-gases are
treated in a combination  wet scrubber and   baghouse  and  are  given  in
Table 27.
                                   58

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Table 27.  RAW WASTE LOADS-ALUMINOTHERMIC  SMELTING
           WITH COMBINATION WET SCKUEEFRS  AND  EAGHOUSE
	Constituent

Suspended Solids
Phosphate
Phenol
Oil
Cyanide (Total)
Cyanide (Free)
Iron (Total)
Manganese
Zinc
Chromium (Total)
Chromium (Hex.)
Lead
Aluminum
Flow
kg/kkg
3.6
0
0
0.048
0
0
0
0.0005
0
2.98
0.95
0
o
I/isisa
26,332
Ib/t on
7.1
0
0
0.095
0
0
0
0.001
0
5.95
1.90
0
g
3£.i§./ton
6,310
Contrary  to  expectations, the covered  furr.aces  which
water uses  higher  than  those   of  open   furnaces   usi^y
scrubbers.   This may be because  water use  ir:  disintegrator
higher, for a particular gas volume, than the  water  use  in
scrubbers.   Most  of  the covered furnaces surveyed ucs=a a
rather than high energy scrubbers.  However, ore  furnace at
equipped with a high energy scrubber, and the  water  use  on
9572  1/mwhr (2529 gal/mwhr) , so  ir would seem that,  this ex
not always be valid.

WASTE CHARACTERIZATION - SLAG PROCESSING
 surveyed had
 high  energy
 scrubbers is
 nigh  energy
isintegrator.
 Plant E  was
ti,at equalled
planation may
The data from Plant E provides information  on  the  raw waste  loads  from
slag  processing  operations.   That  frcm slag concentrating is shown in
Table 28.
                                   59

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Table 28.  PAW WASTE LOADS-SLAG CONCENTRATION  PROCESS
	Congtitugnl

Suspended Solids
Phosphate
Phenol
Oil
Cyanide  (Total)
Iron  (Total)
Manganese
Zinc
Aluminum
Lead
Chromium, (Total)
Flow

kg/kka
46.
0
0
•
•
w
•
.
*
0
•
1/kkg
0


064
0003
543
245
012
569

109

48,259
Ib/ton
91
0
0


1


1
0

gal^/
.9


.128
.0007
.085
.489
.023
. 130

.217
ton
12,750
No raw waste load can be   calculated   directly   for   tne  slag  shotting
process, since tonnage  figures  were not  given.   However, an estimate for
tonnage  can be made from  production  figures.  The charge to alloy ratio
is 3:1 for HC FeMn, meaning  that three  tons  of charge  materials  are
required  to  produce   one ton  of  alloy.  Assuming no losses, this means
that two tons of slag and  particulates are.  produced   for  every  ton  of
alloy.   The  emission  factor  for HC FeMn  is 335 Ib/tori product, so the
slag produced is two tons  minus 335   Ibs =  3665  Ib/ton  alloy.   This
figure  times  operating   load  divided by the electrical energy required
per ton of alloy gives  us  an hourly production figure for slag of 24,452
Ib/hr.  This divided into  the water flow rate gives  a water use of 8,588
gal/ton processed, a suspended  solids raw waste  load of 15.5 Ib/ton, and
a manganese load of 3.87 Ib/ton.

WASTE CHARACTERIZATION-rNONCONTACT  COOLING WATER              .  ..

Plant A provides information on the   waste water   resulting  from  the
recirculation  and  reuse  of cooling  water  on electric  smelting furnaces
producing silicon alloys and utilizing  no  wet  air pollution  control
devices.  A softener is used on one cooling water circuit handling about
50  percent  of  the  total  cooling water flow.  Treatment chemicals are
used with a phosphate reagent used rather   than  a   chrornate.   The  raw
waste  loads  are  given   in Table 29 on the basis  of  the total furnace
power during the sampling  period.
                                   60

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Table 29.  RAW WASTE LOADS--MONCONTACT CCCLING
           WATER—SUBMERGED-ARC FUIxNACHS
	Parameter

Suspended Solids
Phosphate
Phencl
Oil
Iron, total
Manganese
Zinc
Chromium, total
Aluminum
Flow
                             .09
                             .001
                             .00005
                             .002
                             .001
                             .0005
                             .00001
                             .000005
                             .002

                          1/mwhr

                          502.6
                                          ib£/ir>whr
0.
0.
0,
0.
0.
0.
19
00?
C001
004
002
001
0. CO 00 3
0.00001
O.OOt*
132. 8
The data from Plant  F  provide   raw
recirculation  and  reuse of  cooling war. -i
utilizing chromate treatment  for  corrosion
30.
                                              loaas  resulting   from   the
                                            en electric smelziny  rurnaces
                                            inhir-i-.ion, as snown  in Table
                                   61

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Table 30.
RAW WASTE LOADS—NONCONTACT COOLING
WATER—SUBMERGED-ARC FURNACES
        Parameter
Suspended Solids
Total Iron
Manganese
Zinc
Oil
Total Chromium
Hexavalent Chromium
Aluminum
Flow
                     I/mwhr

                      ,71
                      .oil
                      ,007
                      ,14
                      ,08
                      ,26
                      ,0001
                      ,013
                   1/mwhr

                   734
Ibs/mwhr

 5.98
 0.025
 0.016
 0.30
 0. 18
 0.58
 0.0003
 0.03

gals/mwhr

  19u
The cooling tower blowdown  at  Plant  D is   equal   to  35.3  liters   (9.32
gals.)  per mwhr and  the  heat  load at a temperature rise  of  7.2°C  (13°F)
is equal to 255 kg-cal  (1,010  BTU) per mwhr.

The average cooling water usage found at  the  plants surveyed was   53,690
1 (14185 gal)/mwhrr at  an average temperature rise  of 7.6 °C (13.7°F).
                                   62

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                               SECTION VI

                   SELECTION OF POLLUTANT PARAMETERS
Pollutant  parameters  have  been selected by industry categories on the
basis  of  those  which  originate  in  the  production    processes    in
significant amounts and for which control and treatment technologies are
reasonably  available.   The parameters fcr each category  have also been
selected so as to be the minimum number which will insure  control.   The
pollutant parameters selected are shown by category in Taoie  31.

Table 31.  POLLUTANT PARAMETERS FOR INDUSTRY CATEGORIES
          Parameters
II
III
                                                 IV
Heat Content
Suspended Solids
PH
Total Chromium
Kexavalent Chromium
Total Cyanide
Manganese
oil
Phenol
Phosphate
-
X
X
X
X
-
X
X
X
X
-
X
X
X
X
X
X
X
X
X
-
X
>.
X
-
-
X
X
-
—
X
X
A"
X
X
-
—
X
-
X
Although  effluent  flow  volumes  are  not specified in the recommended
guidelines,  its measurement and control is  inif licit  in  attaining  the
pollutant  effluent  loads  specified.   Flow,  of  course,  is   a basic
parameter in that its magnitude indicates the  degree  or  recirculation
and  reuse  practiced  and  the  degree  to  which water conservation  is
utilized.   Additionally,  flow  measurements  will  be  necessary   for
calculating treated waste loads for monitoring purposes.

Since  noncontact cooling water is extensively used ana the magnitude  of
thermal pollution is potentially large, the net heat content is  included
as a pollutant parameter for noncontact  cooling  water.   Additionally,
this  category  requires  limitations  for  chromium  ana phosphate, two
common water treatment chemicals used in recirculating systems..
Oil is considered for all categories, since it  is  a
housekeeping practices, waste stream segregation, etc.
             measure  of  good
                                  63

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Suspended solids are primary  pollutants resulting from wet air pollution
control  devices  and  slag processing.  Suspended solids concentrations
may range up to 7600 mg/1.  They appear to a lesser extent in noncontact
cooling water blowdown from recirculating systems.  The pri determination
in conjunction with metals determinations indicates that excessive  free
acidity  or alkalinity has been neutralized after chroruate reduction and
precipitation, cyanide destruction or  acid  treatment  or  cleaning  in
cooling water systems.

Chromium,  manganese,  iron,  zinc, and aluminum are the principal metals
originating in the production processes.  Manganese  concentrations  may
be as high as 1576 mg/1, while the maximum chromium concentrations found
were  8.36  mg/1  from an electrostatic precipitator spray tower and 121
mg/1  from  an  exothermic  chromium  smelting  operation.    Hexavalent
chromium  is  additionally  included  because  it  may be narmrul at low
levels.

Cyanide is not oxidized in the reducing atmospheres of covered  furnaces
and  appears  in  the waste water.  It must be considered in view of the
potential  danger  as  with   hexavalent  chromium.   Phenols   evidently
originate from electrode binding materials and are considered because of
the  taste-and-odor  producing  potential  of even low concentrations of
such compounds.  They principally appear in the waste water from covered
furnaces, although some may be present in that from open  furnaces.   It
would  seem  that  phenols are oxidized in open furnaces, out not in the
reducing atmosphere of covered furnaces.

Phosphate  is  considered  because  it  has  appeared   in   significant
concentrations  in the plant  survey data and may be controllable insofar
as it is contributed by process sources.

The pollutant parameters  chosen  have  been  those  which  appeared  in
significant  concentrations   from  the  sampling  and analysis conducted
during the plant surveys, and are those parameters amenable to  control.
Other parameters such as dissolved solids, chlorides ana sulfates appear
in  effluents  in  significant  concentrations,  but largely result from
neutralization, softener regeneration, and water reuse; they are thus  a
result  of  treatment  and  there would be no logic in attempting to set
limits.  Many of the metals contained in  the  raw  waste,  particularly
iron,  zinc,  aluminum, and lead are part of the solids generated in the
smelting furnaces.  Plant survey data indicates that tney are controlled
if suspended solids concentrations are controlled.

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                              SECTION VII

                    CONTROL AND TREATMENT TECHNOLOGY

The water  pollution  control  and  -Treatment  technology  used   in  the
ferroalloy industry has generally teen sedimentation in lagoons,  some of
which are very large.  The 8 plants which were surveyed in the course of
the present study covsr the full range of processes used in me  industry
and the various levels of control and Treatment technology.

By  far the most serious pollution problem to the industry nas been that
of air pollution.  Air pollution abatement has been a major  concern  of
the  industry  and  has  involved most of the expenditures lor pollution
control.  Air pollution  control  systems  installed,  being  built,  or
planned  are generally capable of meeting existing state regulations; in
cases where controls have l:een installed  for  5  years  or  more,  such
controls  were  adequate  to  meet then-existing regulations, but may be
marginal insofar as newer regulations are concerned.

The plants surveyed are classified in Table  32 in terms OL tn--   industry
categorization given previously.

      Table 32.  CHARACTERISTICS OF SURVEYED PLANTS
        Category       Processes and Viater^Uses and .Air controls

  A      IV            Baghou.ses being built, recirculated
                       cooling water
  B      II,IV         Disintegrator scrubbers, cnce-tnrouga
                       cooling water usf
  C      II,IV         Sealed furnace, disintegrator  scruboers,
                       recirculated cooling water and scrui^oer water
  D      I,IV          Steam/hot water scrubbers, recirculation of
                       coolinq and scrubber water
  E      I,II,III,     Disintegrator scrubbers, venturi scrubbers,
         IV            once-through water use, slag processing
  F      IV            Baghouse/no air controls, recirculated
                       cooling water
  G      I,III,IV      Electrostatic precipitators, with water
                       sprays, recirculated cooling water,  slag processing
  H      II,IV         Exothermic process, wet scrubbers
                       and baghouse                                  '

The  treatment  and  control  technologies available  for this industry's
waste  water  may  be  grouped  as  follows  for  the principal   waste
parameters:
                                  65

-------
Heat Content:  Cooling porids^  spray ponds, cooling towers

Suspended Solids:  Water recirculatich, lagoons, clarifier-^flocculators^
sand filters

pH: Neutralization

Chromium: Hexavalent chromium  reduction, precipitation, sedimentation

Cyanide: Alkaline chlorinatioh, ozonatibn

Oil: Flotation, skimming^ air  flotation, agglomeration and riltration

Manganese: Neutralization of acid salts, precipitation, sedimentation

Phenol: Biological oxidation,  breakpoint chlorination, activated carbon

Phosphate: Chemical treatment, activated sludge

Cooling  ponds  are  designed  to approach the equilibrium temperature at
which the rate of change of energy at the  water  surface  equals  zero.
This  is, practically speaking, the temperature of the surface waters in
an area and may be about 5.6°C (10°F) above  the  wet-oulb  temperature.
Cooling  ponds  are  capable   cf  limiting  the  temperature rise in the
effluent to 2.78°C  (5°F) over  that  of  the  ambient  water  (or  intake
water,  if  from  a  surface   body).  Spray ponds and cooling towers are
designed to approach  the  wet-bulb  temperature.   They  are  generally
capable  of  a  5-10°F  approach  to  wet-bulb temperature.  Spray ponds
occupy about 10 percent of the area of plain  cooling  ponds,  but  cost
about  twice  as  much  and  entail  operating costs for power.  Cooling
towers cost more than plain  cooling  ponds,  but  occupy  comparatively
little area and can be operated to recirculate water with blowaown of 1%
or  less  of  the recirculation rate.  Additionally, tney may require as
much as  1.8%  of  furnace  power  for  their  operation.   Particularly
difficult  water treatment problems may require a blowdown as hign as 5%
of the recirculation rate.  Treatment chemicals  such  as  chromates  or
phosphates,   added  to  control  scaling  and  corrosion  constitute  a
pollution sourcei

Water recirculation can be used to initially reduce the volume of  water
to  be  treated  for  suspended  solids removal.  Lagoons and clarifier-
flocculators can achieve effluent concentrations of 25 mg/1,  when  well
operated.   Lagoons  are  less expensive in capital and operating costs,
but ' require  much  more  land area.   Sand  filters  achieve  effluent
concentrations  of  10-15  mg/1  and  are  little  more  expensive  than
clarifier-flocculators.

Neutralization is, of course,  simply a matter of adding  an  acid  or  a
base  to  achieve  a  neutral  pH.   This  is most efficiently done with
chemical feed pumps  controlled  by  a  pH  instrument.   A  caustic  or


                                  66

-------
sulfuric  acid  solution can be used and pH controlled to witnin + 0.2 of
the desired pH.

Hexavalent chromium is reduced almost instantaneously at pH levels below
2.5 by sulfur dioxide.  The pH is then raised with lime to about pH  8.2
and  the  reduced  chromium  is settled out.  with proper operation, the
hexavalent  chromium  should  be  completely  reduced.    Tne   effluent
concentration  of  total  chromium  depends  upon  good  pH  control and
adequate sedimentation.  Cyanide is oxidized rapidly to the less harmful
form of cyanate at a pH of 10.5 by alkaline  chlorination.   Cyanate  is
oxidized  to  CO2_  and N£ by continued chlorination at a pH of about 7.0
and a reaction time of about 60  minutes.   Ozonation  is  an  alternate
method for the destruction of cyanide.

Oil  is  generally  removed  from waste water by flotation in lagoons or
clarifiers and the floated oil is skimmed off.  Air flotation  can  also
be  used  with chemical additions to break emulsions ana agglomerate the
oil.

Manganese and iron, to the extent tney are present as  dissolved  salts,
are  removed  by neutralization of the acid salts, at a pH above 9.5 for
manganese and above about 8 for iron.  This is followed Ljy precipitation
and sedimentation.  Ferrous hydroxide, in particular, forms a gelatinous
precipitate  which  settles  slowly.   Sufficiently  high  pH,  adequate
sedimentation,    and   oxidation   is   required   for   low   effluent
concentrations.

Phenol can be  oxidized  biologically  or  chemically  by  cnlorine  and
chlorine  dioxide.   Chlorine  dioxide must, of course, be generated on-
site.  Phenol can also be removed by  absorption  on  activated  carbon.
Biological  oxidation  may  be  unfeasible  for  this  industry with its
generally low BOD levels, although it may be  usable  ir  nutrients  are
aided.   Activated  carbon absorption is a possibility, as is breakpoint
chlorination.

Phosphate can be removed with the use of coagulents such as lime,  iron,
or  aluminum  salts (such as are present in scrubber waste water).  Such
treatment is particularly  effective  if  the  waste  water  is  further
treated  in  an  activated sludge process.  Although an activated sludge
treatment is probably not feasible on ferroalloy waste water,  since  it
requires  other  nutrients  than  phosphates,  a  pH level of 10-11 will
effect phosphate removals of 80-90% if lime, iron or aluminum salts  are
present.

The treatment processes discussed here are conventional.  Tnere does not
appear  to  be  any particular need for more advanced treatment methods.
The main problems are the reduction of  waste  water  volumes  requiring
treatment   to  the  minimum,  design  of  adequately  sized  facilities
(particularly  for   suspended   solids   removal),   proper   operation
(preferably with instrumental control) , and operator training.


                                  67

-------
The  choice  of air polluticn control technology is of utmost importance
in affecting waste water volumes.  Most open furnaces are utilizing  dry
baghouses  and,  of  course,  produce  no waste water effluent from this
source.

There are only two known examples in the world of  dry  dust  collectors
being  used  on  sealed  or covered furnaces,- neither of wnich is in the
United States.  The vast majority of covered furnaces use wet scrubbers;
few open furnaces use wet systems.  Some operations  (such as exothermic)
may require the use of such novel air systems as a wet baghouse.

[Where a dash is shown under net concentration in Tables  33-91,  except
for  those  tables  for  intake  water,  no  analysis  was made for that
parameter.  Where a zero is  shown  under  net  concentration,  but  the
maximum,  minimum  and average concentrations are represented by dashes,
the parameter concentrations found were below the detectable  limit  for
that  parameter.  In other cases where the net concentration is zero, it
is because the average concentration is the sam'e as or less than that of
the intake water. ]
                                   68

-------
PLANT A

This plant, was  built  in  1952  with  five  10  mw  submerged-arc  open
furnaces;  at  the time of our visit, three of these furnaces were still
operating.  A 35 mw furnace was built in 19fc8, and a 20  mw  furnace  is
currently  under  construction.  The large furnace produces  50-854 FeSi.
The other furnaces produce 50* FeSi, proprietary  silicon  oase  alloys,
and  a  rare  earth silicide.-  Chromium alleys have been produced in the
past.  No wet air pollution  controls  are  used;  bagiiouses  are  being
installed.  The water use system is as shown in Figure 7.

All  plant water is supplied from wells and the furnace cooling water is
recirculated.  The No. 1 cooling tower was huilt in 1952 and serves  the
three  10  mw  furnaces.   It is being automated and mouified to include
softeners and strainers, similar to the No. 2 cooling tower.  The No.   2
cooling tower was built in 1968 to serve the. 35 mw furnace.  Proprietary
treatment chemicals and sulfuric acid are use-d in each system.  Blowdown
from  the  No.  1  tower is manual and from No. 2 tow^r is automatically
controlled by total solids levels.  A softener is  usea  in  trie  No.   2
tower  system with bulk salt used as a regererart.  Recircuiated flow in
the No. 1 tower system is 227 I/sec  (3600 gpm) and can be  increased  to
341  I/sec   (5400 gpm) if required by cooling needs.  kecirculation flow
in the No. 2 tower system is 284 I/sec (450C gpm).   The  total  furnace
power during the sampling period was 48.1 mw.  The cooling water use was
thus  38.2  liters  (10.1  gals.)  per kwhr.  Other furnaces exist in the
plant, but have not been recently operated, and there are  no  plans  to
reactivate  them.   The  treatment facilities consist oni> or a settling
lagoon insofar as removal of constituents from the cooling   tower  blow-
down and miscellaneous yard drainage is concerned.

A storm sewer had been installed to by-pass storm run out originating in
the  hills  behind  the  plant.   This  has reduced the wer. weather flow
through the treatment lagoon.

Summarized data from the plant survey are  shown  for  various  sampling
points  as  designated  in  Figure  7  in  Tables  33  through  37.  The
temperature drop across cooling tower No. 1 was determined to  be  6.7°C
(12°F).  The operating power on the furnaces served by tnis tower during
the sampling period was 21.9 mw.
                                  69

-------
                                 Figure 7.

                  PLANT A WATER  AND  WASTEWATER SYSTEMS
                                   DRAINAGE
                        FURNACE
                       "COMPENSATE
BACKWASH
        STORM
        SEWER
 TO
 RIVER
                         WATER
                          ORE FIELD	,,
                          DRAINAGE
                                YARD
                              DRAINAGE
                         LABORATORY
                           DRAINAGE
                                YARD
                              DRAINAGE
                                                        +	v r	>
  SEPTIC
 SYSTEM
OVERFLOW
            VARIES

-------
   Table  33.  ANALYTICAL DATA  -SP A- PLANT A
                LAGOON INFLUENT

Concentrations, mg/1 (except as noted)
Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Average Flow
Minimum Maximum
50
0.01
_
—
-
1.08
1.8
0.99
0.07
0.33
0.07
1.29
-
5.4
= 10.1 I/sec
440
0.01
_
—
—
1.08
6.4
1.78
0.07
0.33
1.00
3.09
-
7.6
. ( 106
Average
183
0.01
_
_
—
1.08
4.3
1.39
0.07
0.33
0.40
2.42
—
6.7
gpm)
Net Averaae
170
0.01
_
0
0
0.76
3.5
1.36
0.03
0.33
0.06
2.34
0
-

   Table  34.  ANALYTICAL DATA  -RP  L-  PLANT A
                LAGOON "EFFLUENT

Concentrations, mg/1 (except as noted)
Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Minimum
20
—
_
-
-
0.91
1.4
1.71
0.05
—
0.34
1.01
—
5.7
Maximum
440
0.01
_
-
-
1.15
58.6
2.06
0.06
—
0.71
1.35
—
7.6
Average
73
—
_
-
-
1.07
25.9
1.85
0.05
-
0.49
1.12
—
7.0
Net Average
60
0
0
0
0
0.75
25.1
1.82
0.01
0
0.15
1.04
0

Average Flow =10.1  I/sec.  (   106
Average Temperature  =13.3°C  (56  °F)
                    71

-------
Table
              ANALYTICAL DATA -SP OPLANT A
               COOLING TOWER #2

Concentrations , mg/1
Constituent Minimum Maximum
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Average Flow =
34

0
0
0
0

0
5

6

38
-
.32
.4
.23
.03
—
.04
.26
-
.9
I/sec,
-
0.
1.
0.
0.
—
0.
5.
-
7.

32
0
36
08

57
79

8
(except as
Average
36

0
0
0
0

0
5

7
—
-
.32
.7
.30
.05
—
.22
.47
-
.3
Net
23
0
0
0
0
0
0
0.
0.
0
0
5.
0

noted)
Average




27
01


39


. ( gpm)
   Table 36   ANALYTICAL DATA -SP^ - PLANT  A
               COOLING TOV7ER #1

Concentrations, mg/1
Constituents
Minimum
Suspended Solids 14
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
-
0.
0.
0.
0.
—
0.
4.
—
6.

53
4
34
03

07
47

6
(except as
noted)
Maximum Average Net Average
500
-
0.
0.
0.
0.
-
0.
5.
-
8.


53
8
38
055

57
26

3
183

0
0
0
0

0
4

7
-
-
.53
.6
.36
.039
-
.31
.83
-
.4
170
0
0
0
0
0
0
0
0
0
0
4
0



.21

.33



.75


Average Flow =  1.55 I/sec..  ( -24.6  gpm)
Average Temperature =15.6°C  (60  °FJ
                   72

-------
Table
       27.
                     ANALYTICAL DATA -SPf.~ PLANT
                         WELL WATER
     Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)

       Average Flow =
            Concentrations, mg/1  (except as noted)
            Minimum  Maximum  Average  Net Average
                       8
                       0.32
                       0.6

                       0.022

                       0.30
                       6.9
                      16
                       0.32
                       1.0
                       0.06
                       0.07

                       0.41
                       0.14

                       7.7
        13
                           I/sec. (
         0.32
         0.8
         0.03
         0.044

         0.34
         0.08

         7.3

        gpm)
          Table 38.   ANALYTICAL DATA -SPA- PLANT B
                        INTAKE WATER
     Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)

       Average Flow =
            Concentrations, mg/1  (except as noted]
            Minimum  Maximum  Average  Net Average
             0.018
             0.4
             1.31
             0.02
                      38
0.016

0.018
1.5
1.37
0.02
        20
                                          0.005

                                          0.018
                                          0.8
                                          1.34
                                          0.02
             0.23      0.23      0.23

             6.5       7.7       6.9

             353  I/sec.  (5,600 gpm)
                           73

-------
PLANT B

This plant has been  operating  since  1939  and  has  four covered  submerged-
arc  furnaces  producing  50%  ferrosiliccn,  75%  ferrosilicon  and  silicon-
manganese-zirconium  (SMZ).  These  furnaces  have a total  racing   of   71.0
mw  and  operated  during the  plant  survey  period at 54.3  mw.  Tne  water
and waste water system  for the plant is  shown in  Figure  8.

The four covered furnaces use  cooling water on  a  once-through  £>asis  and
the  sewage  by  the 350 employees  is treated  at an on-site plant.   The
total effluent is  30,282  cu.  m/day (8 ir.gd) .    Water  is  drawn   rrom a
surface source.

The  fumes from the  four  furnaces  are scrubbed  using s<=ven Buffalo  Forge
(disintegrator) scrubbers,  each usino 15.7b I/sec (250   gpm)   or water.
During  the plant  survey, one  furnace had only  one  scrub£»er, each of the
other furnaces had 2 scrubbers;  a  second  scrubber was oeing  installed on
the first furnace.   The scrubber water is combined  at   a  lift   station
where  lime  and   chlorine are added to'oxidize the cyaniaes proauced in
the covered furnaces. .  The scrubber  water then  flews tnrough  2   lagoons
in  series totaling  30.5  acres in  area and  providing 5-6 days  retention.
The flow then goes to a clariflocculator  where  lime and  a  fldcculant are
added for improved sedimentation.    The   clariflocculator  underflow  is
returned  to  the  first   lagoon  ana the  clariflocculator effluent is
treated with  chlorine,  lime   being  added   if   necessary,  to   destroy
residual  cyanides.   The clariflocculator  overflow effluent then passes
through 2 additional lagoons  in series totaling 2.2 acres  in area.    The
treated scrubber water  is then combined  with  cooling water,  sewage  plant
effluent,  and yard  drainage  and flows through  a  final  lagoon  0.25  acres
in area.  The cooling water temperature   averages  8.33°C   (15°F)   above
ambient.    (The  plant  states  that the  average  temperature rise of the
cooling water is 4-5.5°C  (7-10°F)).

The  total  plant  effluent  was  determined  by   measurements  over  a
rectangular  weir  and  the sewage plant  effluent was measured by bucket
and stopwatch.  The  yard   drainage  flew  was  estimated.    The   furnace
cooling  water  flow was  determined by  difference   and  cnecked by a
calculated chloride  balance.   The  discharge permit  data  for  tnis  plant
indicated   a  cooling  water  flow   of   378.6  I/sec   (6,000  gpm)   and
recirculation of some of  this water.  There is  no chloride buildup  and a
low temperature increment in  this  system.  The  plant states  that  there
is  no  evaporation   associated with recirculation,   which  is done to
increase water velocity in cooling  passages.  This  recirculation  may
account  for  some   of  the difference between  discharge permit  data and
that found during  the plant survey.   In  light  of  the   low  temperature
increment,  however, it   is   doubtful  that  43 &  of the  cooling  water is
recirculated and the flow obtained during the plant survey was judged to
be correct.

-------
The total operating loads on the furnaces during the sampling  was  54.3
mw.   Summarized  analytical  data  are shown for the sampling points as
designated in Figure 8 in Tables 38 through uu.
                                  75

-------
                                        'Figure  8.
                           PLANT B WATER AND WASTEWATER  SYSTEMS
(Tl
     YARD DRAINAGE
                      FURNACE
                      COOLING
                      WATER
     SEWAGE TREATMENT
          PLANT
                                      4-COVERED ELECTRIC
                                      SUBMERGED ARC
                                         FURNACES
                     FOR
                     COOLING
         INFLUENT
         WATER
                                            7-WET
                                           SCRUBBERS
                                  CHLORINE
                                  LIME
          EMERGENCY
          OVERFLOW
DISPOSAL LAGOON
   2.5 ACRES
• 	 ^ • 	 1
LIFT
STATION
l
r
DISPOSAL LAGOON
13.5 ACRES
i
t
DISPOSAL LAGOON
17 ACRES
4 '
* V
(r\
i
UNDERFLOW
LIME FLOCCULANT
i i
•, r i ADirinrriii AT/ID
\~/ »^.I_"IMI i-w. VWL.'-H \y i >
OVERFLOW
                                                             CHLORINE	
                                                             pH CONTROL
                                   OVERFLOW
                  SETTLING  LAGOON

                     0.25 ACRES
SETTLING LAGOON

    I.I  ACRES
  SETTLING  LAGOON

     I.I ACRES

-------
   Table 39.   ANALYTICAL DATA -SPB- PLANT B
                 WET SCRUBBERS

Concentrations, mg/1 (except as noted)
Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Average Flow
Minimum Maximum
968 2,
—
—
1.18
0.20
15.9
2.4
6.1
1.46
0.69
5.62
0.54
1.43
6.2
= 126 I/sec.
242
-
-
3.28
1.57
38.6
7.6
8.9
3.10
1.29
9.05
2.25
1.96
6.4
Average
1,555
—
_
2.49
1.04
24.0
4.5
7.8
2.10
0.99
7.27
1.11
1.71
6.3
Met Average
1,535
0
0
2.48
1.03
24.0
3.7
6.5
2.08
0.99
7.27
0.88
1.71

(2,000 gpm)
   Table 40.   ANALYTICAL DATA -SPG - PLANT
                THICKENER INLET

Concentrations, mg/1 (except as noted)
Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total 'Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Minimum
70
—
- 0.15
0.15
2.58
0.6
0.79
0.94
_
0.43
0.45
6.3
Maximum
96
—
0.36
0.36 ,
2.97
2.2
1.14
1.08
0.29
0.44
0.54
6.9
Average
83
—
0.22
0.22
2.84
1.2
0.95
1.01
0.19
0.43
0.51
6.6
Net Average
63
0 ..
0.21-
0.21
2.82
0.4
0
0.99
0.19.
0.43
0.28
0

Average Flow =  126 I/sec.  (2,000  gpm)
                    77

-------
   Table  41  ANALYTICAL  DATA -SPD- PLANT B
              THICKENER OVERFLOW

Concentrations, mg/1 (except as noted)
Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil , • J
Iron
Zinc .. '
Aluminum
Phenol ;.
Phosphate
Lead .
pH (units)
Average Flow
Minimum Maximum
8
—
—
0..15
0.15
0.88
1/2
0.41
0.38
' —
0.49
0.27
•_
,8 . 2
=. ( 126
86
0.01
—
.0.34
0.34
0.93
3.0
0.50
0.39
"—
' 0.51
. :0.54
0.05
9., 6
I/sec., (2,000
Average
56
—
—
0.21
0.31
0.90
2.2
0.47
0.38
—
0.50
0.41
0.03
9.0
gpm).. .....
Net Average
36
0
• .0
0 . 20
-."."•' 0..20
" -0/8.8
1.4
0
0.36
0., . .
0.50 ..
.0 . 1.8
0 . 03
' -.-... -.

   Table .42   .ANALYTICAL DATA -S.P E - PLANT B
                '.., COOLING WATER

Concentrations, .mg/1
Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol .
Phosphate
Lead
pH (units)
Minimum
4
-
0.
-
0.
0.

0.
o..
-
0.
-
6.


006

025
6

044
47

22

7
Maximum
22

0

0
'o

0
0

:0

. 8

-
.061

.025
.8

.044
.47
-
.22
-
.5
(except as
Average Net
11

0

0
0

0
0

0

7

_
.025
-
.025
.7

.044
.47
—
.22
—
.9
0
0 .
0
Q.
^ .0
'"'o.
0

0.
0.
0
0
0

noted)
Average


020

007


024 '
47




Average Flow  =  217   I/sec.  (3,440 gpm)
                       78

-------
          Table 43.   ANALYTICAL DATA -SPF- PLANT B
                    SEWAGE PLANT EFFLUENT
     Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)

       Average Flow =
Concentrations, mg/1  (except as noted)
Minimum  Maximum  Average  Net Average
 20
  0.01
  1.52
  1.0
  0.33
  0.11
  0.33

  6.31
48
 0.01
 1.52
 2.6
 1.31
 0.11
 0.33

 6.31
  6.6      7.6

1.0  I/sec.  ( 16
32
 0.01
 1.52
 2.0
 0.82
 0.11
 0.33

 6.31

 7.2

gpm)
 12
  0.01
  0
  0
  0
  1.50
  1.2
  0
  0.09
  0.33
  0
  6.08
  0
          Table 44.   ANALYTICAL DATA -SPG - PLANT B
                    TOTAL PLANT DISCHARGE
     Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)
Concentrations, mg/1  (except as noted)
Minimum  Maximum  Average  Net Average
 10
  0.006
  0.006
  0.20
  1.0
  0.24
  0.08
  0.22
  0.11
  0.30

  8.1
70
 0.02

 0.030
 0.020
 0.22
 2.6
 0.28
 0.11
 0.35
 0.12
 0.33

 9.2
35
 C..01

 0.020
 0.010
 0.21
 1.6
 0.27
 0.09
 0.30
 0.12
 0.31

 8.5
15
 0.01

 0.015
 0.010
 0.19
 0.8
 0
 0.07
 0.30
 0.12
 0.08
 0
       Average Flow = 350  I/sec.  (5,556 gpm)
       Average Temperature =20.8°C  (69.3F)
                           79

-------
PLANT C

This plant was built in 1967  and has a single sealed furnace rated at 33
mw.  The principal product  is  silicomanganese.

The water use and waste treatment  system is  shown  in  Figure  9.   The
furnace  off-gases  are   scrubbed   in  a  spray  -ower  and a low energy
(Dingier) scrubber.  Water  is  recycled and reused in both  the  scrubber
system  and  the furnace  cooling water system; the latrer incorporates a
cooling tower.  Makeup for  the scrubber system is attained from blowdown
from the cooling water system.  The scrubber effluent  is  treated  with
potassium  permanganate   to oxidize the cyanides and a flocculant aid to
improve sedimentation in  the  thickener .to  which  all  or  the  scrubber
water  flows.   The  thickener overflow is recycled to the scrubbers and
the underflow is treated  in a  series of  2  lagoons.   Tiie  effluent  of
these  lagoons  and  the  cooling   tower  blowdown are combined and flow
through 2 additional lagoons  in series.  The sanitary sewage is  treated
in  a  package-type plant and  allowed to settle in a small lagoon before
being combined with the   industrial  waste  water  for  discharge.   The
cooling   tower  recirculation rate  is  163  I/sec  (2580  gpm).   The
temperature drop across the cooling tcwer is 1U°C (25.2°F).

Summarized analytical data  are shown for the designated sampling  points
in Tables U5 through 51.
                                   80

-------
                                           Figure  9.

                             PLANT  C  WATER AND  WA.STEWATER  SYSTEMS
CO
         COOLING

          TOWER
                               QWEUSQ
                   BLOW/gsDOWN
               POLYELECTROLYTE
REFUSE
WATER
TANK
i
k
fe

SCRUBBER
KMn04
~CH
^
'-*
i
i_
                                                                            DISCHARGE
                                       ...EMERGENCY
                                       F;~*OVERFLOW
                                                ACTIVATED /
                                                CARBON
                                                FILTERS
SANITARY

 SEWER
                                THICKENER
                                                           I
  LIFT

STATION
                                                           I
                                                        SANITARY
                                                       TREATMENT
                                                         PLANT
                           I
                 CHLORINE
                                                                                 LAGOON

-------
          Table  45.
              ANALYTICAL DATA -SP A- PLANT
                  WELL WATER
     Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)
               Concentrations, mg/1 (except as noted)
               Minimum  Maximum  Average  Net Average
                0.013

                0.51
                0.021
0.017
0.4
0.51
0.029
0.016
0.2
0.51
0.026
                6.9      7.5      7.2

Average Flow = 50.4 I/sec.  (800
          Table  46.  ANALYTICAL DATA -SPB - PLANT
                   COOLING TOWER BLOWDOWN
     Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)
               Concentrations, mg/1 (except as noted)
               Minimum  Maximum  Average  Net Average
                40
                 1.37

                49
                 0.6
                 0.51
                 3.32

                 0.14
                 0.28

                 7.6
50
 3.81

56
 1.2
 0.68
 3.40

 0.24
 0.95

 7.8
45
 2.21

52
 0.9
 0.57
 3.35

 0.19
 0.50

 7.7
44
 0
 0
 2.21

52
 0.7
 0.06
 3.32

 0.19
 0.50
       Average Flow =3.1   I/sec.  ( 49   gpm)
       Average Temperature  = 36  °C  (96.8 °F)
                            82

-------
Table
                     ANALYTICAL DATA -SPC- PLANT
                      SPRAY TOWER SUMP
     Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)
            Concentrations, mg/1  (except as noted)
            Minimum  Maximum  Average  Net Average

            1,280    2,076    1,529    1,528
                0.04     0.04     0.04     0.04
                2.46
                0.49
              271
                2.0
                3.02
               18.9
               38
                0.70
                4.54
                1.17
                7.6
  5.39
  1.29
608
  4.4
  7.91
 21.4
 38
  0.98
  5.23
  4.00
  8.5
  4.08
  0.99
447
  3.5
  5.12
 20.6
 38
  0.79
  4.77
  3.00
  8.1
       Average Flow =69.3 I/sec. (1,100 gpm)
       Average Temperature = 48 °C  (118.4°F)
  4.08
  0.99
447
  3.3
  4.61
 20.6
 38
  0.79
  4.77
  3.00
          Table 4ti    ANALYTICAL DATA -SPD - PLANT c
                     THICKENER UNDERFLOW
     Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)
            Concentrations, mg/1  (except as noted)
            Minimum  Maximum  Average  Net Average

            8,158    39,012   24,397   24,396
               1.99
               0.54
               8.4
  4.90
  0.89
  3.33
  0.68
  8.9
  8.6
       Average Flow =  1.6 I/sec.  ( 25   gpm)
       Average Temperature = 45 °C  (113°F)
  3.33
  0.68

-------
   Table  4£  ANALYTICAL  DATA -SPE- PLANT C
             SEWAGE  PLANT EFFLUENT

Concentrations, mg/1
Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Minimum
2
-
—
-
-
3.
1.
0.
0.
-
0.
-
-
5.





5
0
42
181

04


2
Maximum
8
-
_
-
-
6.
1.
0.
0.
—
0.
-
-
••7





3
6
47
131

29


0
(except as noted)
Average
6




5
1
0
0

0


6

—
_
—
-
.0
.3
.44
.181
—
.17
-
—
.1
Met
5
0
0
0
0
5.
1.
0
0.
0
0.
-
0

Average





0
1

155

17



Average Flow =0.06  I/sec.  (     1 gpm)
Average Temperature  =  19.3  °C (66.7  °F)
   Table  50   ANALYTICAL DATA -SP.F - PLANT C
            SLUDGE  LAGOON EFFLUENT

Concentrations, mg/1 (except as noted)
Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Average Flow
Minimum Maximum
106 3
-
_
1.85
0.32
65
1.4
1.11
1.93
9.4
0.15
1.52
-
7.3
= I/sec.
12
-
—
2.41
1.08
97
2.4
1.64
3.11
11.1
0.36
2.23
0.77
7.7
(
Average
188
-
—
2.15
0.77
75.5
1.9
1.30
2.51
10.0
0.23
1.82
0.50
7.5
gpm)
Net Average
187
0
0
2.15
0.77
75.5
1.7
0.79
2.48
10.0
0.23 '
1.82
0.50


                      84

-------
   Table  rjl   ANALYTICAL DATA -SPG- PLANT  c
              THICKENER OVERFLOW

Concentrations, mg/1 (except as noted)
Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Average Flow
Minimum Maximum
100 2
_
_
5.01
0.73
51
2.8
0.27
1.00
4.1
0.47
1.02
-
7.2
= 67. 7 I/sec.
52
_
_
6.48
1.12
82
4.0
0.43
2.80
9.4
0.86
4.0
0.80
7.7
(1,075
Average
181
_
_
5.60
0.90
71
3.4
0.38
1.73
6.2
0.64
2.05
0.49
7.5
gpm)
Net Average
180
0
0
5.60
0.90
71
3.2
0
1.70
6.2
0.64
2.05
0.49


   Table
ANALYTICAL DATA -SPA  -  PLANT  D
    WELL WATER

Concentrations, mg/1 (except as noted)
Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Minimum
10
—
_
-
-
0.20
-
2.24
0.026
_
_
0.02
—
6.1
Maximum
16
—
_
-
-
0.20
-
2.30
0.026
—
_
0.04
—
7.9
Average
13
—
_
-
-
0.20
-
2.27
0.026
-
—
0.03
-
6.7
Met Average
_
—
_
-
-
-
-
—
_
-
_
-
-
-
Average Flow =16.3 I/sec.  (  259   gpm)
                     85

-------
PLANT D

This  plant has open  submerged-arc  furnaces  which  produce  rerrocnromium,
ferrosilicon,  blocking   chrome,  and   ferromanganese.   Tnrcc   or    the
furnaces are rated at 5.5 rr.w and  the fourth  at  16.5  mw.

These  furnaces  are   equipped  witn   a.  new type  cf  dust-removal system
utilizing waste heat,  from the furnace  to  provide  the   clergy   for   gas
scrubbing  without  the   use  of  exhaust  far.s.   This  system  lias  recently
been installed on four ferroalloy furnaces.   The  reaction   gas passes
through  a heat exchanger,  a nozzle, ar.d a separator.  Tne ueat  from  the
reaction gases is transferred  to  tht-  water  in  the   neat exchanger,
increasing  the  temperature of the wattr to about 177-204°C (350-4 00°F)
and the water pressure to about 21  kg/sq cm  (300 psi) .   As   trie heated
water  is  expanded through the r.ozzit of the scrubber,  partial  flashing
occurs, and the remaining liquid  is atoir.iztd.   Thus,  a two-phase mixture
of steam and small droplets leaves  the nozzle  at  hicm  velocity.    The
reaction  gas  from the  furnace is  -ntrained by this  hiyn  velocity, two-
phase mixture, and  in  the  subsequent  mixing,  -he reaction  gas   is
scrubbed and cleaned.  At the same  timrf,  tb41 action  of me gases leaving
the  nozzle  aspirates  the  reaction  gases  from the  furnace and propels
them through the system.   The. mixture  of steam, qas,  and water   droplets
entrained  with the collected parriculat.es frcn< the  gas  passes through a
separator after discharge from the  mixir.a section.  The  water ana  dust
are  removed  from  the   gas-steam  mixture;  tht gas  leaves the separator
through the stack, and the  water  ana  dust ere  discharged rrom   the
separator  to  a  waste   water treatment system.   Cnemicals and other
treatment are applied to settle the solids and  other  contaminants  from
the  water,  and the  fluid slurry is discharged to settling  ponds.  This
system is illustrated in  Figure  10.   The water   is  then filtered,
softened,  and  returned  to a pump for recycling  to tne heat exchanger.
Makeup water is added to replace  ar.y losses.

The water flow diagram is shown in  Figure 11.  The clarifiers consist of
3 inclined, tube-type clarifier-flocculators in parallel.    Tne  filters
are  3  deep-bed  sand  filters  in parallel; backwash on  tne filters is
controlled by a continuously reading turbidimeter.  The  softener   is  a
fluidized  moving-bed ion  exchange   unit,  rated  at  38  I/sec (600  gpm) .
The particular softener  design is claimed to minimize resin  attrition to
less than 1 percent per  year and  to minimize rinsewater  requirements.

The recirculation rate at the cooling  tower  is  284 I/sec (4500 gpm),  and
the blowdown rate  is 1.3  percent,   or  3.7  I/sec   (5ti.5   gpm).    The
temperature change across the tower is 7.2°C (13°F).

During  the sampling  period, 2 of the  smaller furnaces were  operating as
was the largest furnace.   The products produced were  blocking chromium,
ferrochromium,   and   50%   ferrosilicon.   The  average  daily   power
consumption on the furnaces totaled 695.5 mwhr.
                                   86

-------
Summarized analytical data for various sampling poinrs as designated  in
Figure 11 are shown in Tables 52 through 57.
                                   87

-------
                                         Figure  IO.
                             STEAM/HOT  WATER SCRUBBING  SYSTEM
CO
00
                                                          OFFTAKE
                                                          DUCT
EMERGENCY
 STACK
                                      HEAT
                                      EXCHANGER
                                CLEAN  GAS
                                DISCHARGE
                                 PRIMARY
                                 PUMPS
                                                              NOZZLE

                                                          MIXING  DUCT
                                                        SEPARATOR
                         CLARIFIER
           FURNACE
          'ENCLOSURE
                                                   PUMP HOUSE

-------
                                          Figure  I'.

                           PLANT D WATER  AND WASTEWATER SYSTEMS
PP
BLOW DOWN
                                                         I	L
                                                      SCRUBBERS
               WELL
      MAKE UP TO
      SCRUBBERS p
                                PLANT
                                DISCHARGE  [
                       .DRY SLUDGE
                        DUMP
                      SLUDGE
                      LAGOONS
CLARIFIERS
FIERS ~1

4	J
                                                       FILTERS
                BLOW DOWN-
                         PH
                    ADJUSTMENT
                       CELL
                                             BRINE
                                                                               PUMPS
            TURBIDIMETER
               CELLS
                                                         SOFTENER
                                                                       BLOW DOWN

-------
   Table 5-*   ANALYTICAL DATA -SP B- PLANT  D
            COOLING TOWER SLOWDOWN

Concentrations, mg/1 (except as noted)
Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide"
Free ; Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Average Flow
Minimum Maximum
10
—
_
0.007
-
0.09
0.2
3.08
0.059
0.7
_
1.95
-
6.2
=0.38 I/sec
28
—
—
0.007
-
0.14
0,2
3.15
0.077
0.7
_
2. -77
—
7.8
. ( 6
Average Net Average
19
—
_
0.007
—
0.11
0.2
3.10
0.069
0.7
_
2.54
—
6.8
gpm)
6
0
0
0.007
_
0
0.2
0.83
0.043
0.7
_
2.51
0


Table
              ANALYTICAL DATA  -SPC -  PLANT D
               SLURRY BLEND  TANK

Concentrations, mg/1 (except as noted)
Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Minimum
768
0.10
0.06
-
-
0.60
-
2.47
11.2
10.8
0.03
0.45
0.68
8.7
Maximum Average Net Average
7,644 3
3.37
1.85
0.062
0.020
4.06
1.3
60.
34.
103.
0.48
6.95
4.4
9.3
,070
1.24
0.68
0.031
0.018
1.89
0.70
27.9
25.1
58.6
0.24
3.95
3.03
9.0
3,057
1.24
0.68
0.031
0.018
1.6'9
0.70
25.6
25.1
58.6
0.24
3.92
3.03

Average Flow =21.6  I/sec.  (343.5 gpm)
                    90

-------
          Table 55   ANALYTICAL DATA -SPE- PLANT D
                    CONTINUOUS SLOWDOWN
     Constituent
Concentrations, mg/1  (except as noted)
Minimum  Maximum  Average  Net Average
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)

       Average Flow =
 8
 0.05
 0.2
 0.39
 0.173

 0.02
 0.04
102
  2.24

  0.014

  0.60
  1.6
  0.77
  0.325
  0.6
  0.30
  0.10
38
 0.46

 0.005
 0,
 I.
  25
  0
0.57
0.175
0.2
0.12
0.06
 7.1       11.1     9.6

 6.3 I/sec.  ( 100  gpm)
25
 0.46

 0.005

 0.05
 1.0
 0
 0.149
 0.2
 0.12
 0.03
 0
          Table 56    ANALYTICAL DATA -SPD - PLANT
                     FILTER SUPPLY TANK
     Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)

       Average Flow =
Concentrations, mg/1  (except as noted)
Minimum  Maximum  Average  Net Average
 68
  0.25

  0.020
134
  0.43

  0.029
0.42
0.3
1.53
0.288
0.7
-
0.01
-
9.1
19.2 I/sec
1.23
1.6
6.15
2.51
1.8
0.23
0.18
0.42
10.3
. ( 305
112
  0.31

  0.024

  0.78
  1.1
  3.15
  1.24
  1.3
  0.12
  0.07
  0.14
  9.7

gpm)
         99
          0.31

          0.024

          0.58
          1.1
          0.88
          1.21
          1.3
          0.12
          0.04
          0.14
                          91

-------
                          DRAFT
          Table 57   ANALYTICAL DATA -SPF- PLANT D
                       PLANT DISCHARGE
     Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)
Concentrations/  mg/1 (except as noted)
Minimum  Maximum  Average  Net Average
 60
  0.54
  0.138
  0.014

  0.81
  0.4
  1.06
  0.592
532      186
  1.35     0.87
  0.215    0.177
  0.030    0.025
  8.4
  3.25
  0.61
  7.83
  3.79

  0.05
  0.10
  0.63
  9.6
1.81
0.54
3.79
2.03

0.02
0.06
0.21
8.9
173
  0.87
  0.177
  0.025

  1.61
  0.54
  1.52
  2.00
  0
  0.02
  0.03
  0.21
       Average Flow =  9.8  I/sec.  (  155 gpm)
                           92

-------
PLANT E

This  plant  has been operating since 1951 ana has principally  two areas
where  waste  waters  other  than  cooling  waters  are  generated    and
discharged.    These   two  areas  contain  electric  arc  rurnaces   and
electrolytic cells, respectively.
There are seven
ferrosilicon,
ferromangan ese,
also  contains
furnaces have a
period at 82 mw.
                covered and two op=n submer. ged-arc   furnaces  where   50%
                 silicomanganese,    standard    and    medium     carbon
                and high carbon ferrochromiuir, are produced.   This  area
                metals  refining  and  slag  shotting operations.  These
                total rating of 126 mw and operated  durine,   tne   survey
The  nine  furnaces  use  cooling  water  or.  a or.ce-tnrougn  ijasis.
sanitary sewage -is treated at an on-site plant, and discharges  wi~^
cooling  water.  The total plant effluent is 1.lb X  106  cu. m/day
                    F whioh •; c; or>ni-i r.i-i  u?ater  from  the  plant's
mgd), the majority
mgdj, tne majority
generating station.
                 The total piant erriu*
                   of which is cooling
      The
with  the
   (305.5
    power
The  water
Also shown
survey.

The  fumes
energy type
           and waste water systems for the plant are enown in Figure  12.
           in this figure  are  tne  sampling  points  usea  during   the
            from  the
            scrubbers.
                       furnaces  are scrubbed with
                        There are live venturi and
scrubbers available for
22-32  I/sec  (350-500
                        the nine furnaces.  The  scrubbers   use
                        gpm)  of  the  water when operating.   Tne
                                                   either venturi  or  low-
                                                   12 disintegrator type
                                                                 between
                                                                   metals
refining operation also utilizes a ver.turi scrubber
                                                           scruubcr  water
flows via a common line to the rirst cf two lagoons operated in   series.
The  lagoons  have  a combined surface area of 78 acres.  Trie  wasn  water
from the electrolytic operations mixes with  the  scrubber  waste  water
before entering the lagoons.

The  acid  waste  water  frcm  the  electrolytic operations riows to  the
second of these lagoons where a hydrated lime slurry  is also added  as   a
neutralizing  agent.  This second lagoon also receives the ertiuent from
a flyash removal system at the  power  plant.   The   er fluent   from  the
second lagoon flows to the receiving stream.

A  waste  water discharge from the slag concentrator  flows to  a  separate
4.3 acre tailings lagoon and then to the receiving stream.

Summarized analytical data for sampling points as designated   in Figure
12  are  shown  in  Tables  58 through 74.  The 1971  average temperature
increase in cooling water temperatures over inlet was 3.9°C  (7°F) .
                                  93

-------
                                                                                    Figure 12.
                                                                      PLANT  E  WATER AND WASTEWATER  SYSTEMS
  CHLORINE
                                                                         CHLORINE INFLUENT  WATER
                                                                         ——-HIFROM RIVER
                                                                               FOR MISCELLANEOUS
                                                                               OPERATIONS
VO
                    ' SUBMERGED
                    ARC - FURNACES
  SUBMERGED
ARC - FURNACES
                                                                                                FOR POWER
                                                                                                PLANT
                                  SLUDGE LAGOON NO.)
                                        8.5 ACRES
                                                                        LIME
                                                  SLUDGE LAGOON N0.3
                                                     69.6 ACRES
                     OUTFALL
                       TO RIVER
               OUTFALL
                 TO RIVER
                                                                                                 YARD
                                                         DRAINAGE
OUTFALL
 TO RIVER
OUTFALL
  TO  RIVER
OUTFAIL
  TO RIVER

-------
          Table 58   ANALYTICAL DATA -SPA- PLANT

                 FURNACE A SCRUBBER DISCHARGE
                      Concentrations, mg/1  (except as noted)
	Constituent	  Minimum  Maximum  Average  Net Average

Suspended Solids       210      342      261      228
Total Chromium           0.01     0.01      0.01     0
Hexavalent Chromium                                 o
Total Cyanide       .      -        -                o
Free Cyanide                                        o
Manganese               54       54       54       54
Oil                      1.2      1.2       1.2      1.2
Iron                     5.26     5.26      5.26     4.68
Zinc                    18       18       18       18
Aluminum                 4.45     4.45      4.45     3.78
Phenol                                              0
Phosphate                                           o
Lead                     1.79     1.79      1.79     1.79
pn  (units)               7.0      7.1       7.0

       Average Flow = 28.4 I/sec. ( 450
          Table 59   ANALYTICAL DATA -SPB - PLANT

                 FURNACE B SCRUBBER DISCHARGE
                      Concentrations, mg/1  (except as noted)
	Constituents     Minimum  Maximum  Average  Net Average

Suspended Solids       318      426      373      340
Total Chromium           0.09     0.09      0.09     0.09
Hexavalent Chromium       -
Total Cyanide            0.87     0.87      0.87     0.87
Free Cyanide              -        -        -        -
Manganese              256      256      256      256
Oil                      1.6      1.6       1.6      1.6
Iron                    18.0     18.0     18.0     17.4
Zinc                    4B.       48       48       48
Aluminum                13.0     13.0     13.0     12.3
Phenol                   0.22     0.22      0.22     0.22
Phosphate                 -        -        -       0
Lead                     5.6      5.6       5.6      5.6
pH  (units)               6.4      6.9       6.7

       Average Flow = 25.2 I/sec. ( 400  gpm)
                              95

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          Table 60.   ANALYTICAL DATA -SPC- PLANT

             METALS REFINING SCRUBBER DISCHARGE
     Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)

       Average Flow =
Concentrations, mg/1 (except as noted)
Minimum  Maximum  Average  Net Average
 874
   0.06
 597
   1.2
   1.82
   0.46
   0.87
1,674    1,204
    0.06     0.06
  597
    1.2
    1.82
    0.46
    0.87
 597
   1.2
   1.82
   0.46
   0.87
   7.8       8.7      8.2

 22.11/sec. (   350gpm)
         1,171
             0
    0
    0
  597
    1.2
    1.24
    0.44
    0.20
    0
    0
    0
          Table  61.  ANALYTICAL DATA -SPD - PLANT E
                  SLAG SHOTTING WASTEWATER
     Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)
Concentrations, mg/1 (except as noted)
Minimum  Maximum  Average  Net Average
 132
   0.03
  54
   1.2
   0.28
   0.13
  10.5
   7.3
 302
   0.03
  54
   1.2
   0.28
   0.13
  10.5
   7.4
217
  0.03
 54
  1.2
  0.28
  0.13
 10.5
  7.5
184
  0

  0
  0
 54
  1.2
  0
  0.11
  9.8
  0
  0
  0
       Average Flow  =110.3  I/sec.  (1,750  gpm)
                                96

-------
          Table 62   ANALYTICAL DATA -SP E- PLANT E
                 FURNACE C SCRUBBER DISCHARGE
                      Concentrations/ mg/1 (except as noted)
	Constituent	  Minimum  Maximum  Average  Net Average

Suspended Solids       264      364      317      284
Total Chromium           0.57     0.57     0.57     0.41
Hexavalent Chromium       -
Total Cyanide            0.16     0.16     0.16     0.16
Free Cyanide              -
Manganese               21.9     21.9     21.9     21.4
Oil                      1.8      1.8      1.8      1.8
Iron                     3.19     3.19     3.19     2.61
Zinc                     8.7      8.7      8.7      8.7
Aluminum                 7.1      7.1      7.1      6.4
Phenol                   0.09     0.09     0.09     0.09
Phosphate                0.32     0.32     0.32     0.32
Lead                     0.26     0.26     0.26     0.26
pH (units)               7.3      7.3      7.3

       Average Flow = 50.4 I/sec. ( 800  gpm)
          Table  63   ANALYTICAL DATA -SPF  - PLANT E
                FURNACE D SCRUBBER DISCHARGE
                      Concentrations, mg/1  (except as noted)
	Constituents     Minimum  Maximum  Average  Net Average

Suspended Solids       268      414      343       310
Total Chromium           0.10     0.10     0.10      0
Hexavalent Chromium       -
Total Cyanide            0.96     0.96     0.96      0.96
Free Cyanide              -
Manganese                4.22     4.22     4.22      3.73
Oil                      1.6      1.6      1.6       1.6
Iron                     4.00     4.00     4.00      3.42
Zinc                     3.00     3.00     3.00      2.98
Aluminum                 1.68     1.68     1.68      1.01
Phenol                   0.15     0.15     0,15      0.15
Phosphate                0.50     0.50     0.50      0.50
Lead                     1.03     1.03     1.03      1.03
pH  (units)               4.4      4.4      4.4

       Average Flow =50.4 I/sec. ( 800  gpm)
                             97

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          Table 64.   ANALYTICAL DATA -SP G- PLANT E
                FURNACE  1. SCRUBBER DISCHARGE
     Constituent
                      Concentrations, mg/1  (except as noted)
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)
Minimum
3



1







,244
0.
_
—
,576
6.
51
178
0.
-
11.
8.

50



94


09

7
6
Maximum
4,140
0.
_
—
1,576
6.
51
178
0.
-
11.
8.

50



94


09

7
7
Average Net Average
3,753
0.
_
—
1,576
6.
51
178
0.
-
11.
8.

50



94


09

7
6
3,720
0.
0
0
1,576
6.
51
177
0.
0
11.


34



36


09

7

       Average Flow =44.1  I/sec.  ( 700  gpm)
          Table  65.  ANALYTICAL DATA -SP  H - PLANT E
        FURNACE  E SCRUBBER SETTLING BASIN DISCHARGE
     Constituents
                      Concentrations, mg/1  (except as noted)
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)
Minimum
3,



1,








348
0


322
1
7
89
178


9
8

.17
_
—

.0
.16


—
—
.1
.5
Maximum Average
11,364
0


1,322
1
7
89
178


9
8
6
.17
_
-
1
.0
.16


-
-
.1
.6
,080
0


,322
1
7
89
178


9
8

.17
_
-

.0
.16


—
—
.1
.6
Net Average
6,047
0.
0
0
1,322
1.
6.
89
177
0
0
9.


01



0
58




1

       Average  Flow = 44.1  I/sec.  (  700   gpm)
                             98

-------
          Table  66   ANALYTICAL DATA -SP  I- PLANT
                SLAG CONCENTRATOR WASTEV7ATER
                      Concentrations, mg/1  (except as noted)
	Constituent	  Minimum  Maximum  Average  Net Average

Suspended Solids       856      872      864      831
Total Chromium           2.04     2.04      2.04     1.88
Hexavalent Chromium                                 o
Total Cyanide             -       0.013     0.007    0.007
Free Cyanide              -
Manganese                4.39     4.81      4.60     4.11
Oil                      0.2      2.2       1.2      1.2
Iron                     5.8     14.6     10.2      9.6
Zinc                     0.22     0.22      0.22     0.20
Aluminum                10.7     10.7     10.7     10.0
Phenol                    -        -        - '      o
Phosphate                                           o
Lead                                                0
pH  (units)               6.1      6.2       6.2

       Average Flow = 107.ll/sec. (1,700 gpm)
          Table  67   ANALYTICAL DATA -SP J - PLANT
                SLAG TAILINGS POND DISCHARGE
                      Concentrations, mg/1  (except as noted)
	Constituents     Minimum  Maximum  Average  Net Average

Suspended Solids       46       90       62        29
Total Chromium          0.02     0.16     0.09      0
Hexavalent Chromium                                 0
Total Cyanide           0.006    0.006    0.006     0.006
Free Cyanide             -
Manganese               0.95     1.26     1.08      0.59
Oil                                                 0
Iron                    1.14     1.54     1.32      0.74
Zinc                    0.032    0.058    0.048     0.026
Aluminum                0.72     1.13     0.86      0.19
Phenol                  0.25     0.25     0.25      0.25
Phosphate                                           0
Lead                     -        -         -        0
pH  (units)              6.2      6.9      6.4

       Average Flow =107.1 I/sec.  (1,700
                             99

-------
   Table 68   ANALYTICAL DATA -SP K- PLANT  E
              LAGOON #3 INFLUENT

Concentrations, mg/1 (except as noted)
Constituent
Suspended Solids
Total Cnromium
Hexavalent Cnromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Average Flow
Minimum Maximum Average Net Average
32
0.55
0.190
-
-
24.4
0.4
0.86
4.22
1.44
—
-
—
6.7
=447.3 I/sec
972
1.2
0.205
-
-
26.1
0.4
1.49
7.90
2.60
—
-
' 0.06
7.0
. (7,100
183
0.77
0.198
-
-
25.4
0.4
1.28
5.55
2.04
_
-
0.04
6.8
gpm)
150
0.61
0.198
0
0
24.9
0.4
0.70
5.53
1.37
0
0
0.04


   Table 69   ANALYTICAL DATA  -SP  L  -  PLANT E
              LAGOON  #3 EFFLUENT

Concentrations, mg/1
Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Minimum
2
0



86

0
0
0



7

.08
—
-
-

-
.27
.22
.11
—
-
—
.0
Maximum
30
0

0

93
0
0
0
0

2

7

.08
-
.008
-

.4
.43
.46
.21
-
.73
—
.2
(except as
Average
15
0

0

91
0
0
0
0

0

7

.08
-
.005
-

.2
.35
.34
.15
-
.9
-
.2
noted)
Net Average
0
0
—
0.
0
91
0.
0
0
0
0
0.
0




005


2




9


Average Flow =  632.8l/sec.  (10,045  gpm)
                      100

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   Table 70.   ANALYTICAL DATA -SP M- PLANT
              INTAKE RIVER WATER

concentrations, mg/1 (except as noted)
Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Minimum
24
0.16
_
_
—
0.49
—
0.54
0.022
0.67
—
—
—
7.2
Maximum
38
0.16
_
_
—
0.49
0.2
0.62
0.022
0.67
_
-
—
7.2
Average
33
0.16
_
—
-
0.49
—
0.58
0.022
0.67
_
-
—
7.2
Net Average

_
_
_
_
-
_
_
_
—
_
_
_

Average Flow = 13,366   I/sec.  ( 212,150
   Table 71   ANALYTICAL DATA -SP  N - PLANT E
            COOLING WATER DISCHARGE

Concentrations, rag/1 (except as noted)
Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Minimum
90
6.6
-
-
-
0.053
—
3.42
0.045
4.28
—
1.98
—
3.8
Maximum
176
6.6
—
0.014
-
4.61
0.4
32.
0.045
4.28
—
1.98
-
7.2
Average
125
6.6
—
0.005
-
1.58
0.3
15.0
0.045
4.28
-
1.98
-
5.4
Net Average
92
6.4
0
0.005
-
1.09
0.3
14.4
0.023
3.61
0
1.98
0

Average Flow = 3,571  I/sec.  (  56,680
gpm)
                      101

-------
          Table  /^   ANALYTICAL DATA -t>F c~ ri^i*. £,
      COMBINED SLAG SHOTTING & COOLING WATER DISCHARGE
     Constituent
Suspended Solids
Total Chromium
nexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)

       Average Flow =
               Concentrations, mg/1 (except as noted)
               Minimum  Maximum  Average  Net Average
                148
                  0.02
                 19.1
                  1.0
                  3.72
                  0.049
                  4.95
 192
   0.02
  19.1
   1.0
   3.72
   0.049
   4.95
170
  0.02
 19.1
  1.0
  3.72
  0.049
  4.95
                  7.5      7.5      7.5

                50.41/sec. (   SOOgpm)
137
  0.02

  0
  0
 18.6
  1.0
  3.14
  0.027
  4.28
  0
  0
  0
          Table 73   ANALYTICAL DATA -SP P  - PLANT E
                 FLY ASH INFLUENT TO .LAGOON
     Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Pnenol
Phosphate
Lead
pH  (units)
               Concentrations,  mg/1 (except as noted)
               Minimum  Maximum  Average  Net Average
               1,246
20,156   7,667
         7,634
                  6.6       7.0     6.7

Average Flow = 70.9 I/sec.  (1,125 gpm)
                              102

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          Table  74.  ANALYTICAL DATA -SP  Q- PLANT E
                 FLY ASH INFLUENT TO LAGOON
     Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Pnenol
Phosphate
Lead
pH (units)
Concentrations, mg/1  (except as noted)
Minimum  Maximum  Average  Net Average
 510
5,200    2,209
         2,176
   6.6
    6.8
   6.7
       Average Flow =70.9  I/sec.  (1,125 gpm)
          Table '/b   ANALYTICAL DATA -SP'A - PLANT F
                        INTAKE WATER
     Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)

       Average Flow =
Concentrations, mg/1  (except  as  noted)
Minimum  Maximum  Average  Net Average
 17
  U.01
  0.026
  1.0

  0.008
 17
  0.01
  0.026
  1.0

  0.008
17
 0.01
 0.026
 1.0

 0.008
  7.3      7.3       7.3

 25.2 l/sec.  ( 400   gpm)
                             103

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PLANT F

This plant utilizes seven electric arc furnaces  to  produce  a  product
line  including  50%  ferrosilicon,  low carbon ferrochromesiiicon, high
carbon ferrochromium, low carbon ferrochromium and silicon  metal.   The
furnaces range in size from 10 mw to 36 mw with a collective capacity of
142  mw.   No  wet  air  pollution devices are used; baghouses have been
installed on some furnaces.  The water use system is as shown in  figure
13.

All  plant water is supplied from wells and the furnace cooling water is
recirculated.  Blowdown from all three cooling towers  is  automatically
controlled  by  total  solids  levels.   Flow  rate in the cooling tower
serving 4 furnaces with a capacity of 51 mw  is  76  I/sec  (1200  gpm) .
Bleed-off   from  this  unit  is  5  I/sec   (80  gpm)   or  6.6%  of,  the
recirculating flow.  Another cooling tower serving a 20 mw furnace has a
flow rate of 50 I/sec  (800 gpm) and a bleed-off of 1 I/sec (20  gpm)  .or'
2.5% of the recirculating flow.  Two additional furnaces with a capacity
of  65  mw are served by a 316 I/sec  (5000 gpir.) recirculating flow and a
bleed-off of 13 I/sec  (200 gpm) or H% of the flow.  Water  treatment  in
the cooling system consists of a chromate based proprietary compound and
algaecides.

Except  for the overflow from septic tanks and isolated roor drains,  the
cooling system bleed-off is the major source  of  the  plant  discharge.
Yard drainage resulting from surface run-off is collected and transfered
to  a  small  off-site  lagoon.   Under  normal  conditions  there is no
discharge from the lagoon as accumulated waste water  either  evaporates
or drains through the lagoon bottom.

With  6  furnaces  operating  during the sampling period at 92.8 mw,  the
cooling water use was thus 17.15  1/kwhr  (4.53  gal/kwhr).   A  limited
number  of  samples were collected at this plant and the analytical data
are summarized in Tables 75 through 77.  The temperature drop across the
cooling tower is 5.6°C  (10°F).

A slag concentration process is used at this plant which utilizes  water
on  a completely closed recirculation system, the only discharge of slag
fines being to a closed lagoon, i.e., a lagoon  with  no  outlet.   This
process was not operating at the time of our visit.
                                   10U

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                   Figure  13.
    PLANT  F  V^ATER AND WASTE WATER  SYSTEMS
                  SLAG CONCENTRATOR
                      ILAGOONJ
(No' Discharsej      (No  Discharge)
                                              TO RIVER
                       105

-------
Table  76   ANALYTICAL DATA -SPB- PLANT F
         COOLING TOWER SLOWDOWN

Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Average Flow =
Concentrations, mg/1
Minimum Maximum
14
10
0


0
1
0
6




5
12.

.8
.015
—
—
.093
.4
.11
.98
—
—
—
—
.9
6 I/sec
14
10.
0.
_
—
0.
1.
0.
6.
—
—
-
—
5.
. (

8
015


093
4
11
98




9
200
(except as noted)
Average
14
10
0


0
1
0
6




5

.8
.015
_
—
.093
.4
.11
.98
_
_
—
—
.9
Net
0
10

0
0
0
0
0
6
0
0
0
0

Average

.8
_


.067
,.4
.11
.97





gpm)
Table  77   ANALYTICAL DATA -SP C - PLANT F
             PLANT  DISCHARGE

Concentrations, mg/1 (except as noted)
Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phospnate
Lead
pH (units)
Average Flow
Minimum Maximum
14
13.6
0.008
0.010
-
0.370
4.2
0.58
6.98
0.67
_
—
—
6.5
= 20.8 i/Sec
14
13.6
0.008
0.010
-
0.370
4.2
0.58
6.98
0.67
_
—
—
6.5
. ( 330
Average
14
13.6
0.008
0.010
-
0.370
4.2
0.58
6.98
0.67
_
— '
—
6.5
gpm)
Net Average
0
13.6
_
0.010
—
0.344
3.2
0.58
6.97
0.67
0
0
0


                     106

-------
PLANT G

This plant has two 35 mw open furnaces which produce ferrociiromium and a
slag  concentration  operation.  At times ferrochrcmesilicon is  produced
here.  The water flow diagram for the plant is shown in Figure 14.   Air
pollution  control  is by means of electrostatic precipitators which are
preceded by spray towers.  The gases from the furnaces  are  conditioned
by the water sprays in the towers in order to improve tne perrormance of
the precipitators; ammonia is added to the spray water.

The water supply is purchased city water and originates from welis.  The
cooling  water  used  on  the furnaces is ^circulated tnrough a cooling
tower at the rate of 316 I/sec (5000 qpm) .  The sr^ray  towers  remove  a
portion  of  the.  particulates  from  the  furnace  gases  prior to the
precipitators; trie resultant slurry passes through settling uasins  near
the  furnaces  and  then  a  lagoon which has Leer; excavated rrom a slag
pile.

The slag concentrator is a sink-float process in which  slag  rines  are
separated   from   larger,  usable  slag  particles  and  in  turn  from
recoverable metal.  The products ar~ thus slaq for sale  ana  metal  for
reuse; the waste is a slurry of slag fines.  The waste stream is treated
in 2 small lagoons in series prior to discharge to a stream.

Plant production has been reported at 245 kkcis (270 short tons)  of alloy
per  day.   Reference 32 indicates a factor of 4.2 mwhr per ton,  i.e., a
furnace load of 1,134 mwhr per day.  Analytical data are  summarized  in
Tables 78 through 83, for sampling locations designated in figure 14.
                                  107

-------
                                           Figure 14.
                             PLANT G WATER AND WASTEWATER  SYSTEMS
o
00
             SPRAY
             TOWER
                          CITY
                         WATER


FURNACE






t

COOLING
TOWER
i
r



FURNACE


                 SETTLING
                   BASIN
       SPRAY
       TOWER
SETTLING
 BASIN
                                       •©-+
               LAGOON
                                                                LAGOON
                                                                LAGOON
                                                                               SLAG
                                                                          CONCENTRATION

-------
Table 78.   ANALYTICAL DATA -SP/
            INTAKE CITY WATER
                                           PLANT
     Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Pnenol
Phosphate
Lead
pH  (units)
            Concentrations, mg/1 (except as noted)
            Minimum  Maximum  Average  Net Average
             0.030
             0.2
             0.13
             0.159
0.030
0.2
0.14
0.159
             6.9
7.9
0.030
0.2
0.13
0.159
7.3
       Average Flow =20.5  I/sec.  ( 325  gpm)
          Table 79.  ANALYTICAL DATA -SPl - PLANT
                   COOLING TOWER SLOWDOWN
     Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
oil  .
Iron
Zinc
Aluminum
Phenol
Phospnate
Lead
pH  (units)

       Average Flow =
            Concentrations, mg/1  (except as noted)
            Minimum  Maximum  Average  Net Average
             18
              3.23
              1.43
              0.094
              0.2
              0.19
              0.52
              0.98

              0.05
40
 3.35
 1.57
 0.094
 0.4
 0.46
 0.71
 0.98

 0.15
25
 3.31
 1.49
 0.094
 0.3
 0.32
 0.65
 0.98

 0.12
              7.3      8.4      8.0

            1.6  I/sec.  (  25  gpm)
25
 3.31
 1.49
 0
 0
 0.064
 0.1
 0.19
 0.491
 0.98
 0
 0.12
 0
                            109

-------
          Table 80    ANALYTICAL DATA -SPC- PLANT G
                    SPRAY TOWER DISCHARGE
     Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
                      Concentrations/ mg/1  (except as noted)
Minimum
4,134
2.66
-
-
-
1.68
0.2
1.77
0.75
4.34
-
0.01
-
7.3
Maximum
6,104
8.36
0.49
-
-
14.0
0.6
3.50
5.28
23.0
-
0.02
-
8.6
Average Net Average
4,980
4.76
0.32
-
-
8.15
0.3
2.58
2.45
11.28
-
0.02
-
8.1
4,873
4.76
0.32
0
0
8.12
0.1
2.45
2.29
11.28
0
0.02
0

       Average Flow =  1.1 I/sec.  (  17.5gpm)
          Table  B1   ANALYTICAL DATA -SPD - PLANT G
                   SETTLING BASIN EFFLULUT
     Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)
Concentrations, mg/1 (except as noted)
Minimum  Maximum  Average  Net Average
 204     1,898
   3.48      7.44
   2.89

   1.27
   2.67
   7.8
   7.7
 3.81

 5.87
 6.83
29.0
 8.9
       Average  Flow =  3.8  I/sec.  (   60
       784
         5.29
  3.33
  0.4
  2.95
  4.75
 21.9

  0.03

  8.3

gpm)
784
  5.29
  0
  0
  0
  3.30
  0.2
  2.82
  4.59
 21.9
  0
  0.03
  0
                             110

-------
   Table  £2   ANALYTICAL DATA -SPE- PLANT  G
                PLANT DISCHARGE

Concentrations, mg/1 (except as noted)
Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Average Flow
Minimum Maximum
96
2.26
_
—
—
0.«7
0.4
0.45
0.35
1.60
—
0.01
-
8.0
= 3.8 I/sec
104
2.81
_
_
—
1.45
2.0
0.83
1.15
3.49
—
0.01
-
8.2
. ( 60
Average
101
2.52
_
_
_
1.2U
1.1
0.60
0.84
2.57
_
0.04
—
8.1
qpm)
Net Average
101
2.52
0
0
0
1.17
0.9
0.47
0.68
2.57
0
0.04
0


   Table  B3   ANALYTICAL DATA -SPF -  PLANT G
           SLAG PROCESSING DISCHARGE

Concentrations, mg/1 (except as noted)
Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Minimum
26
0.55
0.16
-
-
0.50
0.8
0.98
0.088
0.27
—
-
—
8.4
Maximum
2,894
4.54
0.45
—
-
10.8
1.0
5.33
3.36
37.0
—
-
—
9.5
Average
1,250
2.61
0.30
—
-
4.14
1.0
4.38
1.65
14.1
—
-
—
8.9
Net Average
1,250
2.61
0.30 '
0
0
4.11
0.8
4.25
1.49
14.1
0
0
0

Average Flow = 0-66 i/sec.  (  10.4  gpm)
                      111

-------
PLANT H

Chromium  metal  is  produced  at this plant by an aluminothermic process
using chromium oxide produced  by the exothermic reaction of  wood  flour
and  sodium  dichromate.   The production  of  chromium  oxide  is  not
considered here.

The off-gases from the aluminothermic process are cleaned  in  a  unique
"wet  baghouse"  system  shown in  Figure  15.   Water sprays and a wet
dynamic scrubber preceed the baghouse and an air heater which raises the
gas temperature above the dewpoint to prevent bag  clogging.   The  bags
are  cleaned  by  water sprays between each batch^type operation and are
dried prior to the  next  cycle.   The  waste  water  effluent  contains
suspended solids and hexavalent chromium as the principal pollutants.

The waste water is treated batchwise in a series of ruober lined lagoons
as  shown  in  Figure  16.   There are three reduction basins which each
treat one batch of waste water from the  baghouse.   Treatment  time  as
measured  from  the  filling of the basin to discharge of treated waste-
water to the sludge lagoon should take  approximately  two  hours.   Two
56,775   liters    (15,000  gallon)  tanks  are  provided  for  treatment
flexibility and storage.

Sufficient sulfuric acid addition capacity  is  provided  to  lower  the
waste  water  pH  to about 3.0.   (It is at this point pH level where the
chemical reduction of the  chromium  is  most  efficient.)   At  maximum
conditions,  the daily sulfuric acid requirements are expected to be 454
kg/day (1,000 Ibs/day).

Sulfur  dioxide  added  to  the waste   water   through   chlorine-type
sulfonators  is  the  reducing agent  for  the  treatment process.  The
theoretical reduction of chromium requires approximately .5 kg  (1  Ib.)
of  sulfur  dioxide  for  every kg  (2  Ib.)  of chromates (CrO3) to be
reduced.  On a daily basis, 136 kg  (300 Ib.) of SO2 is required.

Upon completion of chemical reduction, sodium hydroxide is added to  the
basin  to  raise the pH to form an insoluble chromium hydroxide from the
reduced chrome.  Approximately 36 kg/day (80 Ib/day) of sodium hydroxide
is required under maximum flow conditions.

Diffused air agitation is provided to completely mix the reduction basin
and to prevent the settling of precipitated  solids  before  the  waste
water  is  released  to the sludge lagoons.  The air supply capacity was
based on providing 0.054 cu. m/hr/gal.  (0.5 cu.  ft./hr/gal.)   of  waste
water to be mixed.

The  rubber-lined sludge lagoons have an approximate volume of 1,741,100
liters (460,000 gallons) when  gravity flow is used  from  the  reduction
basins  to the lagoons.  Pumping the treated waste water, however, could
theoretically utilize the full 3.5 m (11 ft.) depth of  the  lagoon  and


                                  112

-------
would  almost  triple  their capacity.  Currently, gravity flow is used,
but provisions have been made for the later addition or pumps if needed.

Sludge production is expected to approach U5U kg/day   (1,000  lb/  day) .
Approximately  six  months  of sludge storage is provided cefore removal
would be required.  This storage capacity will allow   for  180  days  of
continuous operation at the maximum flew and chromium  concentrations.

Analytical  data  from  the  plant  survey  are  summarized in Tables 8U
through 91 for sampling points indicated in  Figure  16.   The  measured
temperature  rise  of  the  cooling water was 6°C  (10.0°F).  The cooling
pond is designed for a maximum rise of 2.78°C (5°F), and is 61 m X 67   m
(200 ft. X 220 ft.).
                                  113

-------
                                                                         Figure 151
                                                                 DIAGRAM OF*WET BAGHOUSE* SYSTEM
FIRING  CUBICLE
    WITH
 FIRING POT
                           DUCTS WITH
                           WATER SPRAYS
                                                        BAGS CLEANED BY
                                                     INTERNAL WATER SPRAY
                         TRAP
                                                                                                      MAIN  EXHAUST FAN
                                        SLURRY TO
                                          DRAIN
                                                  (CLEANED GAS  TO  ATMOSPHERE)

-------
               Figurf-  16.
PLANT H  WATER  AND WASTEWATER  SYSTEMS
GASES

EXOTHERMIC
SMELTING
OPERATION


t
i
BAGHOUSE
        «-
                CITY
                WATER
     TREATMENT

       (LINED)
SEASONAL  BY-PASS
                        •
TO STREAM
-^ 	 	
»

i 	
THtRMAL
POND
(UNLINED)
i
*
t
^
SETTLING
 LAGOON
 (LINED)
                                     POLISHING
                                      LAGOON
                                      (LINED)
                                                    COOLING
                                                    WAI EK

-------
          Table  84   ANALYTICAL DATA -SP*- PLANT
                      INTAKE CITY WATER
     Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)

       Average Flow =
Concentrations,  mg/1 (except as noted)
Minimum  Maximum  Average  Net Average
  0.026

  0.22
  0.016
           0.026

           0.29
           0.016
  5.6      5.7

28.4 I/sec.  (  450
 0.026

 0.25
 0.016
                    5.6
          Table 35   ANALYTICAL DATA -SPB - PLANT
                BAGHOUSE WASTEWATER DISCHARGE
     Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)
Concentrations/ mg/1 (except as noted)
Minimum  Maximum  Average  Net Average
 106
 101
  17
   0.040
   1.2
   0.04
   0.002
          220
          121
           44
            O.U51
            2.b
            0.04
            0.003
136
112
 37
  0.048
  1.8
  0.04
  0.002
136
112
 37
  0
  0
  0.022
  1.8
  0
  0
  0
  0
  0
  0
  12.3
           12.4
 12.3
                            116

-------
          Table ot    ANALYTICAL DATA -SPC - PLANT
                 TREATED BAGHOUSE WASTEWATER
                      Concentrations, mg/1  (except as noted)
	Constituent	  Minimum  Maximum  Average  Net Average

Suspended Solids       674      748      713      713
Total Chromium         114      114      114      114
Hexavalent Chromium      0.047    0.363    0.162    0.162
Total Cyanide                                       o
Free Cyanide                                        o
Manganese                0.41     0.73     0.54     0.51
Oil                      0.8      2.0      1.3      1.3
Iron                     2.64     3.73     3.27     3.01
Zinc                     0.90     1.53     1.27     1.25
Aluminum               127      130      129      129
Phenol                    -        -        -       0
Phosphate                0.41     0.50     0.46     0.46
Lead                      -        -        -       0
pH  (units)               4.7      6.2      5.4

       Average Flow = 100,303 I/da (26,500 gal/da)
          Table  b7   ANALYTICAL DATA -SFD - PLANT H
                  SETTLING LAGOON DISCHARGE
                      Concentrations/ mg/1  (except as noted)
	Constituents     Minimum  Maximum  Average  Net Average

Suspended Solids       58       70       66        66
Total chromium         17.9     18.3     18.1      18.1
Hexavalent chromium     0.189    0.218    0.208     0.208
Total Cyanide            -        -        -        0
Free Cyanide                                        0
Manganese               0.70     0.70     0.70      0.67
Oil                     3.4      3.4      3.4       3.4
Iron                    0.24     0.42     0.32      0.06
Zinc                    0.77     0.77     0.77      0.75
Aluminum               31       31       31        31
Phenol                                              0
Pnosphate               0.05     0.05     0.05      0.05
Lead                                                0
pH  (units)              4.9      4.9      4.9

       Average Flow =      i/sec.  (      gpm)
                            J.17

-------
Table  08   ANALYTICAL  DATA -SPE- PLANT
       POLISHING LAGOON DISCHARGE

Concentrations, mg/1 (except as noted)
Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)
Average Flow
Minimum Maximum
3b
7.13
0.214
_
-
0.92
4.0
0.17
0.44
15.3
_
0.05
—
5.2
= 0.32 I/sec
56
7.56
0.261
_
—
0.92
4.0
0.17
0.44
15.3
—
0.05
_
5.2
. ( 5
Average
47
7.40
0.245
_
—
0.92
4.0
0.17
0.44
15.3
_
0.05
_
5.2
gpm)
Net Average
47
7.40
0.245
0
0
0.89
4.0
0
0.42
15.3
0
0.05
0


Table  SrJ  ANALYTICAL DATA -SPF - PLANT
              PLANT  DISCHARGE

Concentrations, mg/1 (except as noted)
Constituents
Suspended Solids
Total Chromium
Hexavaient Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units;
Average Flow
Minimum Maximum
_
0.37
0.024
-
-
0.22
2.0
0.27
0.023
_
—
0.05
-
5.2
= 18. 9 I/sec
22
0.81
0.090
0.016
0.016
0.40
4.0
0.34
0.074
—
—
0.05
-
6.1
. ( 300
Average
6
0.57
0.057
0.009
0.009
0.32
2.7
0.29
0.048
—
_
0.05
—
5.7
gpm)
Net Average
6
0.57
0.057
0.009
0.009
0.29
1.8
0
0.032
0
0
0.04
0


                    118

-------
          Table 90   ANALYTICAL DATA -SPG- PLANT H
                      PLANT WELL WATER
     Constituent
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
Iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH (units)

       Average Flow =
Concentrations, mg/1  (except as noted)
Minimum  Maximum  Average  Net Average
  0.037
  4.6
  0.52
  0.011
 0.037
 4.6
 0.57
 0.011
 0.037
 4.6
 0.55
 0.011
  0.05     0.05     0.05

  5.2      5.3      5.3

3.01 i/sec.  (  48  gpm)
          Taole 91   ANALYTICAL DATA -SPH - PLANT H
                        COOLING WATER
     Constituents
Suspended Solids
Total Chromium
Hexavalent Chromium
Total Cyanide
Free Cyanide
Manganese
Oil
iron
Zinc
Aluminum
Phenol
Phosphate
Lead
pH  (units)

       Average Flow =
Concentrations, mg/1  (except as notea)
Minimum  Maximum  Average  Net Average
 40
  0.44
  0.38
  1.45
  2.2
  1.49
  0.060
  0.27
40
 0.44
 0.38
 1.45
 2.2
 1.49
 0.060
 0.27
40
 0.44
 0.38
 1.45
 2.2
 1.49
 0.060
 0.27
  6.0      6.0       6.0

18.6 I/sec.  (   295  gpm)
40
 0.44
 0.38
 0
 0
 1.42
 2.2
 1.24
 0.044
 0.27
 0-
 0
 0
                            119

-------
In  Figure  17,  a  waste   treatment scheme is shown in wnich all of the
waste  constituents  for  which  guidelines  have  been   developed   in
Categories  I  and II can be  reduced to minimal concentrations.  Not all
waste  streams   will   contain   all   constituents   and   appropriate
modifications of this general  scheme can be made to reduce costs.

The  first  step consists of  raising the pH of the waste stream to about
11 and the addition of sufficient chlorine to maintain a free  residual,
followed by sedimentation.  In this step, phenol is oxidized, cyanide is
oxidized  to cyanate, and the  phosphates and manganese are precipitated.
In the second step, additional chlorine is added and tne pri  is  lowered
to  7.0  by  a  suitable  acid.  With a reaction time of 60 minutes, the
cyanate is oxidized to CO2  and N2_.  In the third step, the pH is lowered
to 2.5 and sulfur dioxide is  added.  Allowing  a  reaction  time  of  30
minutes,  the  hexavalent   chromium is reduced -o trivaient.  The fourth
step consists of raising the  pH to 8.2, adding  a  polyelectrolyte,  and
allowing  sedimentation.    At this point, the trivaient chromium will be
removed and final clarification accomplished.  With a  sufficiently  low
overflow  rate  and addition  of flocculants in sufficient quantities, an
effluent solids concentration of 25 mg/1  of  suspended  solids  can  be
attained and metals reduced to low levels.

Sand  filtration of the final clarifier effluent, with backwash returned
to the clarifier, can reduce  suspended solids concentrations to 15  mg/1
or  less.   After  filtration,  the  water . may  be recycled back to the
scrubbers.

For a waste stream containing no phenol or cyanide, but witn  hexavalent
chromium,  a  single  initial  clarifier operated at a pH of 10 and with
polyelectrolyte addition should  reduce  phosphate  ana  metals  to  low
concentrations  and  no  chlorination  is  necessary.  In this case, the
first two steps of Figure 17  are combined into one, and the remainder of
the process steps are as shown.

For a waste stream containing no hexavalent chromium,  £>ut  with  phenol
and cyanide, the chromium reduction step is eliminated.
                                   120

-------
                   Figure 17.  Diagram of Waste Water Treatment  System
           ^ PHENOL
   60 MIN.
RETENTION
@ J?H 11.
               60 MIN.
             RETENTION
             @ pH 7.

           UNDERFLOW
   45 MIN.
 RETENTION
 @ pH 2.5
                                                    UNDERFLOW
              Mn,Fe,
              Pb,P04
            FILTER BACKWASH
                            Al,Zn
        CLARIFIER
        EFFLUENT
  I	

  FILTER
  EFFLUENT
                  I
                 *_
 SAND
FILTERS
COAG
AID
^ v

L.
(
Ci
7
S(

                                           OR
                                          CAUS-
                                           TIC
                                                               SLUDGE
                                                             DEWATERING
                               0.5 GPM/FT2
                               RISE  RA.TE
                               @ pH  8.2
   NEUTRALIZATION
     TANK

UNDERFLOW	
SLUDGE
DISPOSAL
OR
METAL
RECOVFRY

-------
The  treatment  scheme  shown   is  based upon those at Plant B  (alkaline
chlorination), Plant D  (alkaline precipitation of  metals,  ana  use  of
sand filters), and Plant H  (reduction of hexavalent chromium) .  The high
hexavalent chromium levels  found at Plant K may have occurred Because of
the  aeration  system,  which   may  have  oxidized some of the trivalent
chromium back to the  hexavalent  state.   Additionally,  tne  pH  after
reduction of hexavalent chromium should be raised to over 8, rather than
around  5  to  6, so that more  chrome would be precipitated.  it is felt
that the treatment system at Plant D, although  the  most  sophisticated
and  producing the best overall effluent of any plant in the survey, was
not  operating  in  an  optimum manner,  as  evidenced  by   the   high
concentrations  of  suspended   solids after the clarifier (112 mg/1) and
after sand filtration  (38 mg/1).  These concentrations are  much  higher
than  would  be  expected and may have been caused by non-quiescent flow
into the clarifier and  insufficient backwashing of the sand filters.

Other treatment and control methods, as presently used in tne  industry,
do not produce reasonably good  effluent qualities.

For  example.  Plant  C used potassium permanganate for the oxidation of
cyanide.  Cyanide was  only  reduced  to  3.33  mg/1  in  tne  thickener
underflow,  compared  to 4.08 mg/1 in the raw waste.  KMnO4 should be at
least as good an oxidizing  agent as chlorine, and yet little cyanide was
oxidized at this plant.  Higher dosages may have induced more oxidation,
but the cost of chlorine is less than that of permanganate, and for that
reason chlorination was selected as one of the steps  in  tne  suggested
treatment  scheme.   Although   the cyanide destruction system was fairly
ineffective, this plant stood out in  the  recirculation  and  reuse  of
water from scrubbers and cooling,  some of the blowdown from the cooling
tower  was  used as makeup  water for the scrubber system, and 97ft of the
scrubber water was recirculated, the only blowdown being  the  clarifier
underflow.

Plant  E  used a large  lagoon  (70* acres) for sedimentation, and fly ash
from a captive power plant  was  added to this lagoon.  This  may  explain
the  low  values  for   suspended  solids obtained in the lagoon effluent
(from 2 to 30 mg/1), while  other plants, such as Plant B, had  suspended
solids  levels  of  83  mg/1 in the lagoon effluent.  A lagoon may be an
alternative to clarifier-flocculators, but land may not be available  at
all locations.

The control and treatment technologies which have been identified herein
are identified as applicable to the various industry categories in Table
92.
                                   122

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Table 92.  CONTROL AND TREATMENT TECHNOLOGIES t»Y CATEGORY
          Treatment
Category.  Technology

   I          1

              2

              3
  II
 III
  IV
              1
              2
              1

              2

              1
                                  	Description	
Chemical treatment, clarifier-floccuiators,
recirculation at. the scrubber
Chemical treatment, clarifier-floccuiators,
sand filters and process water recirculation
Dry dust collectors for air pollution control

Chemical treatment, ciarifier-floccuiators
Chemical treatment, clarifier-fIcccuiators,
sand filters and process water recirculation

Clarifier-floccuiators, chemical
treatment  (if necessary)
Total process water recirculaticn

Once-through water use, cooling ponds,
or alternate treatment for control
of thermal pollution
(Chemical treatment of blowdown, ir presently
recirculating ccoiing water)
Cooling towers, recirculation, chemical
treatment of blowdown
It  should  be  noted  that  with  thf.  exception of tne slag processing
operations, the raw waste loads  and  final  effluent   loads  have  been
calculated  in terms of mwhr as the production basis.   Ihis was  aone  for
the following reasons, after examining  the  other  possible  oasis   (kg
(tons) ) :

1.  Uncontrolled  emission  factors   (upon  which  the  raw  waste loads
depend), are more uniform  over  the  various  types  or  products  when
expressed as kg (lb)/mwhr, rather than as kg/kkg  (Ib/ton).

2. Power usage is already such a large factor in production costs  (about
30*)   that  an  increase  in  power   consumption so that tne permissible
effluent discharge would be higher is very unlikely.
3. Power usage is very well monitored at  the
with a continuous automatic recording device.
                                                furnace  itselr,  usually
                                  123

-------
4.  Furnaces  are commonly  referred to  in the  industry  as  MO mw1 or  '35
mw1, rather than '50 ton' or  '150  ton1,  as  is  common   practice  in   the
steel industry.

5.  The  tonnage  which may be  produced for a  given  power  consumption is
fairly wide  (factor of 10)  and  depends   on  the   product,  and  numerous
products  can be produced in  a  given  furnace.  Use of Kg/kKg  (Ib/ton)  as
limitations would involve the permit  writer ir. writing  a  permit  with
many  different  conditions.    The reader  may   refer   to  Table 18  for
comparisons of power usage  per  ten for  various products.

Aggregate raw waste loads,  representing for   some   parameters  such   as
chromium  and  manganese the  maximum  lead which might be expected in  the
waste, are shown in Tables  93 through 96.   The manganese concentrations,
for example, would probably only be encourterea at these levels  from a
furnace producing manganese products.

The loads were calculated from  flows  and concentrations  as follows:

load  (kg (Ib) /mwhr)  = mass flow  rate  (kg(lb)/hr) x concentration t  (106 x
furnace power  (mw) )

load   (kg/kkg(Ib/ton))  =   mass flow rate  (kq(ib)/hr)  x concentration T
(amount processed  (kkg (tons)/hr) x 106)

The heat load is calculated by  the tcrn-ula  q = me (dt) t-  i-,  where  q   is
the-  heat  load  per  mwhr, m is the  maps flow rate  (kg(li»)/hr, c is  the
constant  pressure  heat  capacity  (kg-cal/kg°C(BTU/lb°F),   dt  is   the
temperature  difference  (°C(°F)) between the ccoling water discharge  and
the receiving stream, and P is  the furnace  power  consumption  (mw).

Furnace power may be calculated by dividing the number  oi  megawatt-hours
used in the furnace in a 24 hour period by  24  hours.

Tables 93-96, describing raw  waste and  treated effluent  loads, have been
constructed on the following  bases:

Category I - Open Electric  Furnaces  with  Wet   Air Pollution  Control
Devices.

Raw  Waste  Load  - Flow based  upon the total  water  flow in the scrubber
[113.6 I/sec  (1800 gpm) ] rather than  effluent  water  flow  at Plant   E,
sample point G from the scrubber [44.2  I/sec  (700 gpm) J.   Concentrations
of  suspended  solids  and  manganese  at   that   sample  point  adjusted
accordingly to compensate for increased flow.  Phosphate and  oil  loads
taken  from  Plant  D,  Sample  point  C,   and concentrations  adjusted
accordingly.  Chromium concentrations taken from  Plant  G,  sample  point
C.
                                   124

-------
Treatment  Level  1  -  Concentrations shown are those achievable by the
treament system as  shown  in  Figure  17,  less  th-s  sand  filter  and
recirculation  portions  and are generally somewhat higher than those at
Plant D, sample point E.  Loads are based upon concentrations shown  and
a water use of 6382 1/mwhr (1686 gal/mwnr) .

Treatment  Level  2 - Concentrations based on entire treatment system as
shown in Figure 17, including the sand filter and recirculation, and are
generally somewhat higher than those at Plant D, sample point E.   These
levels  would  require better operation of the treatment system than was
necessary in Level 1.  Loads based upon blewdown rate of 7ti3 1/mwhr  (207
gal/mwhr) .

Treatment Level 3 - Based upon use of a dry GUST collection  system  for
air  pollution  control,  which  results  ir  no discharge of waterborne
pollutants to navigable streams.  This type of dust collection equipment
is much more widely used than wet scrubbers: on this type of rurnace.

Category II - Covered Electric Furnaces and  Other  Smelting  Operations
with Wet Air Pollution Control Devices.

Raw Waste Load - Concentrations and loads as at Plant b, sample point B,
except that chromium concentrations are taken from Plant G, sample point
C,  and  manganese  concentrations  taken  from Plant C, sample jjoint C.
Loads calculated from Plant B, sample point E, flow.

Treatment Level 1 - Concentrations same as  for  Category  I,  treatment
level  1,  with  the  exception that cyanide concentration is based  upon
that found at Plant B, sample point  D.   Loads  in  kg   (ii>)/mwhr   were
calculated using the flows found at Plant 5, sample point D.

Treatment  Level  2  -  Concentrations same- as tor Category I, treatment
level 2, with cyanide concentration based or Plant P,  sample  point  D.
Loads  in  kg  (Ib)/mwhr based on 10t>C 1  (260 gal)/mwhr being blown  down
from the recirculation system.

Note: Loads  for  exothermic  and  other  nonelectric  furnace  smelting
operations  based  on  water usage three times higher (per ton) tnan for
electric furnaces  (per mwhr)

Category III - Slag Processing

Raw Waste Load - Maximum of Plant E, sample point I, or sample point D.

Treatment Level 1 - Eased on use of clarifier-flocculators.

Treatment  Level  2  -  Eased  on  recirculation  of  all  water   after
precipitation of fine suspended solids in clarifier-flocculators.

Category IV


                                  125

-------
Raw  Waste  Load - Concentrations based upon once-througn water usage as
at Plant B, sample point E.   Flow and heat load based upon average water
flow and measured temperatures  at plants visited.  However, it should be
recognized that any time water  is recirculated through a cooling  tower,
concentrations  will  be increased by evaporation, and -chat chromates or
phosphates will be added  to  the  water  for  corrosion  control.   For
comparative  purposes,  the   maximum concentrations which were found for
the primary pollutants at any plant are shown below.
                 Once-through
                 cooling Water
                     (mg/1)

Suspended Solids       11.0
Total Chromium         0
Hexavalent Chromium    0
Phosphate              0.22
Slowdown trom
Pecirculation System
     (mg/1)

       183.
        13.6
         1.49
         2.42
Treatment Level  1 - Concentrations and heat load based upon once-through
cooling  water   use,  with  application  of  cooling  ponds   to   limit
temperature  rise to  2.78°C  (5°F) above that of ambient water  (or intake
water,  if  from a   surface   body).    For   those   plants   presently
recirculating  cooling water,  limits achievable by chemical treatment of
blowdown.

Treatment Level  2 - Heat load  based  upon  a  blowdown  rate  of  5&  of
recirculation rate in a cooling tower, with a temperature rise of 2.78°C
(5°F)  above  that  of ambient water  (or intake water, if from a surface
body).  Other limits  achievable by treatment of blowdown.

The 24-hour maximums  are generally twice the 30 day averages  and  based
upon  maximum  concentrations  found at exemplary plants, or those which
might be attained during system upsets or the like.   In tne case of  oil
and  phenol,  and phosphate in Category IV, Level 1,  the limitations are
1.5 times the 30 day  average,  and  for  hexavalent  chromium,  they  are
three times the  30 day average.

STARTUP AND SHUTDOWN  PROBLEMS

There have been  no problems of consequence identified an connection with
the  startup or  shutdown of production facilities insofar as waste water
control and treatment is concerned.   Cooling  water,  tor  example,  is
usually  allowed to  flow  or recirculate during short-term production
stoppages, and as often as not, scrubber water continues to flow  during
such  periods.   There  might  be  some  upsets in undersized lagoons or
clarifiers used  in once-through systems if the water  flow  is  abruptly
started after a  shutdown.  Proper operating procedures can easily handle
such  occurences  and there would be little or no effect in sufficiently
large facilities.
                                   126

-------
Loss of power can effect, most of the treatment, sysrems such as  chemicals
addition for flocculation, cyanide destruction, or  chromium  reauction-
precipitation.  In such cases, however, the production process  also will
stop and little effect on waste water treatment would result.
                                  127

-------
                                                                Table 93  INDUSTRY CATEGORY I
                                                         OPEN FURNACE WITH WET AIR POLLUTION CONTROLS
CO

Raw Waste Load 30
Constituents
Suspended Solids
Total Chrcr.ium
Kexavalent
Chron-.ium
Mansanese
Oil
Phenol
Phosphate
Flow
pH
ks/'nwhr
24.0
.078

.005
10.07 .
.011

.010
gal/awhr
4335

lb/r.whr
52.8
.172

.012
22.17
.'025

.'023

Value
7.2
!r,s/l kg/mwhr
1460 .160
4.76 .0032

.32 .0002
613 .032
.7 .045
.0032
.635 .0064
1/tnwhr
16,410

Level 1 Effluent Level 2 Effluent
Day Average 24 hr Maximum 30 ^Day Average . 24 hr X.nxinun
Ib/mwhr
.352
.007

..0004
. .070
.098
.'.007
.0141
gal/mwhr
1686

ma/1 kg/mvhr Ib/aiwhr
25.0
0.5

0.03
5.0
7.0
. 5
1.0

Value
6.0-9.0
.319
.006

.0006
.064
.064
.004
.013


.703
.014

.0014
.141
.141
.010
.028
1 /rawhr
6382

rag/1 kg/mwhr
50 .012
1 .0004

.1 .00001
10 .0039
10 .0055
.7 .0002
2.0 .0001


lb/-vhr
.026
. 0009

.00002
.0086
.012
.0003
.0002
gal/mx-rlir
207

r.t- / 1 k
15.0
0.5

0.01
5.0
7.0
0.2
0.1

Value
6.0-9.
024
0008

00002
DOS
008
0003
0002

0
o/'rv.'hr
.052
.0017

.00004
.017
.017
.0007
.0003
1/ir.whr
783

r.c/1
30
1.0

.02
10
10
.4
.2



-------
            Table 94 INDUSTRY CATEGORY II
COVERED ELECTRIC FURNACES AND OTHER SMELTING OPERATIONS
         WITH KET AIR POLLUTION CONTROL DEVICES



Suspended Solids
Total Chromium
t-'oxavaler.t
O.ro-iura
Total Cvanide
M.?.r.".~.r>ese
Oil
Phenol
Phusphase
K)
V£>
Flow

PH

kp,
13
0

0
0
3
0
0
0.

i~-
Ra
/r."hr
.02
.040

.003
.021
.74
.033
.061
009

1/rawhr
w Waste
Ib/~-,:hr
25.57
O.OS3

0.006
0.046
8.24
0.033
0'.134
0.020

Lead
r.g/1
1555
4.

0.
2.
447
4.
7,
1.



30
kg/r.whr

76

32
49

5
27
11
1
0.
0.

0.
0.
0.
0.
0.
0.

209
004

0003
002
042
059
004
008

1/rawhr
2210



6
Value
.0-9.0
8365











Level 1 Effluent
Day Average
Ib/rwhr
.461
0.009

0.0006
0.005
0.092
0.129
O.C09
0.01S

gal/rawnr
2210


!«R
25
0

0
0
1
7
0
1





/I

.5

.03
.25
.0
.0
. 5
.0



Value
6.0-9.0
24 hr Mr.xitnura
kf./nivhr lb/~wlir r.^/1
0.419
O.OOS

0.0003
0.004
0.034
0.034
0 . 005
0.017





0
0

0
0

0
0
0

1/TBW
8365


.922
.018

.0018
.009
.184
.184
.013
.037

hr



50
1.0

0.1
0.5
10
10
0.7
2.0





k
0
0

0
0
0
0
0
c





30
S/^-hr
.0.16
.0005

.00001
.0003
.005
.007
.COO 2
.0001





Level 2
Dny Average
Effluent:
4 hr M^x-i
iTiUTt!
Ib/pvhr ir.p./l ku/^vhr ib/V.vhr -,s>/l
0
0

0
0
0
0
0
0

p.



.035
.0012

.00002
. 0006
.012
.016
.0005
.0002

al/rawlir •
280


15
0.5

0.01
0.25
5
7.0
0.2
0.1



Value
6.0-9.
0.032
0.001

0.00002
0.0005
o.on
o.o;i
0.0004
0.0002




0
0.071
0.002

0.00005
0.001
().•'! 2 3
0.023
o.cooa
C.0005

I/r-hr
1060


3:i
1.0

0.02
0.5
10
:o
0.4
0.2






-------
                                                         Table  95   INDUSTRY  CATEGORY  III
                                                                   SLAG  PROCESSING
Ul
o

Raw Waste Load


Susaended Solids
Total Chromium
Manganese
Oil

Flow

pH
kg/kkg
processed
46.0
.10'9
2.87
.064

Ib/ton
processed mg/1
91.9 864
.217 2.04
5.74 54
.128 1.2
al/ton 1/kkg
Level 1. Effluent
30 Day Average 24 hr Maximum
kg/kkg
processed
1.330
0.026
0.266
0.372

12,750 53,100


Value
6.2


Ib/ton
processed fflg/1
2.659 25
0.053 .5
0.532 5
0.745 7
gal/ton 1/kkg
12,750 53,100
Value
6.0-9.0
kg/kkg
processed
2.659
0.053
0.532
0.532
gal/ton
12,750

6
Ib/ton
processed is
5.319
.106
1.054
1.064
1/kkg
53,100
Value
.0-9.0

B/l
50
1
10
10





-------
Table 96  INDUSTRY CATEGORY IV
     NONCONTACT COOLISG WATER

Raw Waste Load
Cc-.-.stituer.ts
Suspended Solids
Total Chroniun
Hcxavalcnt
Chror.iu"
Oil
Phosphate

Heat Content

Flow

?H
kn/r.-.chr Ib/awlir ir,g/l
1.590 1.30
0.0005 0.001

0.0005 0.001
0.038 0.083
0.012 0.026
kg-cal/mw'nr
408,000
.al/^-'hr
14,185
Value
7.0
11.0
.01

.01
0.7
0.22
ETU/nwhr
1,621,000
1/rwhr
53,690


Level 1 Effluent
30 Day Average 24 hr Maxiir.ua
kg/ir.whr Ib/mwhr' 'T.~/l kp/rr.v.-hr lb/rawiir ng/1
1.343 2.95.9
0.027 0.059

0.002 0.00.4
0.376 0.828
0.161 '0.355
ks-cal/nwhr
149,000
gal/raw
14,185


25.0 2.686 5.917 50
0.5 0.054 0.118 1.0

0.03 0.005 0.012 0.1
7.C 0.537 1.183 10
3.0 0.269 0.592 5.0
BXU/ssvhr ks-cal/ir.vhr BTU/rawhr
592,000 298,000 1,184,000
hr 1/rawhr
53,690
Value
6.0-9.0
Level 2 Effluent
30 Day Average 24 hr Hnxiriun
k{;/swhr Ib/r.-.-.chr ras/l ky/p-.v.'hr
0.067 O.J4S 25 0.134
0.001 0.003 0,5 0.003

0.00003 0.00006 0.01 0.00005
0.019 0.041 7.0 C.027
0.004 0.009 1.5 O.OOS
ks-cal/ir.whr 3TU/rawhr kg-cal/ro
7,500 ' 30,000 14,900
gal/nwhr
710
Value
6.0-9.0
lb.'nr.,-:;r ms/1
0.296 50
0.006 1.0

0.0001 °-02
0.059 10.0
0.013 3.0
;v-hr BTU/Ewhr
59.000
1/nwhr
2,685



-------
                              SECTION VIII

                COST, ENERGY AND NCNWATER CH'AI.ITY ASPECT


Capital  and  operating  cost  information  was obtained  from  each  plant.
surveyed.  The capital costs  (per  mvv  capacity)   for  water   treatment
systems  at  the  plants surveyed varied from  $^528  (for  a  cooling  water
system, including coolinq towers, etc.) to $27,507  (for a  scrubber  and
cooling  water  treatment  and  recirculation  system).   Operating  costs
varied from a low of $0.021/rnwhr (for spray tower waste water   treatment.
and  cooling  tower  operation),  to  a high cf ^0.770  (lor scruboer  and
cooling water treatment and recircuiation).

Capital costs are given in terms or  ir&tailed  capacity  and   operating
costs  in  terms of units of production =ind alt-o in  terms or waste  water
flows.  These costs were based upon cost or capital  at. an interest  rate
of 8 percent, and a depreciation period or lr>  years.

Capital  costs  have  been  adjusted  to  August, 1971 dollars using  tne
Chemical Engineering Plart. Cost Index   (iS57-SS=100) .   Tnis   index  has
been indicated by a consultant to ri I:*-. Ferroalloys Association  to  ue best
indicative  of  cost changes in the ir.austry.  Operating  costs nave been
adjusted when necessary on the basis'-; cf ar. average  of  j.5   percent  per
year.

Lagoon  costs were taken from Reference 31.  Power  costs  Were  calculated
on the basis of flow rates and pumping head, and have  ueeu assumed   at
one  cent  per kwhr, which is the cost used ir. the  EPA-TFA  Air Pollution
Study  (Ref. 32) .  This estimate hat ceen ccr.firmed   by  Ihe Ferroalloys
Association as being equal to the ov-ragv cost in the  industry.

The  following  bases  were  used  rcr cost calculations  oy Category  and
Treatment Level:

Category I, Treatment Level 1.

Costs were developed for the treatment system  as snown in ngure  17,   on
the  basis of a 63.1 I/sec (1000 gem) flow rate.  At a water use  of 6362
1/mwhr [1686 gal/mwhr], this is equivalent,  to  the  flow  rate  from  a
furnace  operating  at  35  mw.  The costs include  mecnanicai  equipment,
tanks, piping, valves, electrical, engineering, installation,  etc.  They
are  based  upon  the  complete  system  less  the   sand   filter    and
recirculation  and  may, therefore, be somewhat high,  since a  ^articular
plant may not require all the treatment  steps.   The  investment  costs
will  probably  be  less (per mw) for a plant  larger tnan the  model,  and
greater for a plant smaller than the model.  Unless  a  giant's  product
line  and  furnace  types  justified  it,  it  would  probably be  more
economical to install one treatment system for the  entire plant.
                                  133

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Operating and maintenance costs  at this level  of  estimation  are  best
figured  as  a percentage of  capital costs for similar type plants.  The
"Inorganic Chemicals Industry Profile" indicated for 59 plants"  surveyed
operating  costs  per  annual unit  of  production  equal to 28* of the
capital cost per annual unit  of   production.   The  operating  costs  at
Plant  C are equal to  23.4% per  year of the capital cost.  The operating
costs at Plant D are equal to 23.0% of the capital cost.  The  operating
costs  at  Plant  B  are  equal   to 30.9# per year of tne capital costs.
Operating costs are thus estimated on the basis of 30% per year  of  the
estimated capital cost, prorated as at Plant C.

Category I, Treatment  Level 2.

Costs  expanded  from  Level  1,  above, to include costs oi recirculation
and sand filter, with  a proportionate increase in annual  ana  operating
costs.

Category I, Treatment  Level 3.

No  direct  comparison to waste  water treatment and control costs can be
made.  However, investment and annual  costs  for  scrubber  systems  vs
those  for  fabric filter systems (all on 30 n?w furnaces) have been made
for  four   products:    Std.   (High   Carbon    (HC))   ferromanganese;
silicomanganese,  HC   ferrochromium and 50% ferrosilicon  (Ref. 32).  The
costs for scrubber systems include  some  water  treatment  -  a  slurry
settler and two filters for slurry dewatering.  These costs are shown in
Table  99.  Although the investment costs for a fabric filter system are
the same as, or only slightly lower than those for  a  scrubber  system,
annual  costs  are  about half.   This differential in favor of the 'dry1
systems could be expected to  increase markedly  if  any  advanced  waste
water  treatment  were utilized.   Additionally,  because  of the lower
pressure drops required, less power is required for the operation of the
fabric filter system.

Category II, Treatment Level  1.

Costs were developed as for Category I, Level 1.  63.1 I/sec  (1000  gpm)
at  a  use  comparable to that  at Plant E, sample point B, (8365 1/mwhr
[2210 gal/mwhr]), is equivalent  to the flow from a furnace operating  at
27  mw.   As  before,  the investment cost per mw will be somewhat higher
for small plants and less for large plants.

Category II, Treatment Level  2 and 3.

Same as for Category I, Level 2,  but based on 27 mw furnace.


Category III, Treatment Level 1.
                                   13(f

-------
Costs were calculated for two clarifier f loccula tor s, wica the necessary
piping and pumps and other appurtenances.  costs were based upon the use
of 53,148 1/kkg (12,750 gal/ton) processed.

Category III, Treatmenr Level 2.

Costs are greater than for Level I by the addition of   pumps  ana  pipes
necessary for recycle.

Category IV, Treatment Level 1.

Costs for a cooling pond calculated at 315.5 I/sec  (5,000 gpm) and 2.2°C
      approach to equilibrium temperature.
Category IV, Treatment Level 2.

Costs were taken at the average for Plant A arid Plant C cooling systems.
Added  to  this  was an estimate for the cost of reducing  tne hexavalent
chromium which may be present.  (phosphate removal is less costly) .

The costs for each are summarized in Tol'.lrrs 97 and 98.
                                  135

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                            Table 97.   TREATMENT LEVEL COSTS ON UNIT OF PRODUCTION BASIS
                                (costs on basis of mw and mwhr.unless noted thus*)
u>

Annual Costs ($
Industry Category
and Treatment Level
Category I:
Treatment Level 1
Treatment Level 2
Category II:
Treatment Level 1
Treatment Level. 2
Category III:
Treatment Level 1
Treatment Level 2
Category IV:
Treatment Level 1
Treatment Level 2
Investment
($ per mw or

17,143
21,063

22,222
27,303

2,526*
2,604*

1,266
8,444
tpd) Capital

0.103
0.127

0.134
0.165

0.344*
0.357*

0.007
0.049
per mwhr or ton)
Operating Cost
Depreciation less Power Power Total

OU38
0.169

0.178
0.219

0.459*
0.485*

0.010
0.065

0.606
0.745

0.785
0.965

0.421*
0.421*

0.0
0.354

0.(M2 0.859
U.O.L5 1.056

0.016 1.113
0.019 1.368

0.051* 1.28*
0.051* 1.31*

0.0 0.0.17
0.044 0.512

-------
                           Table 98  .   TREATMENT LEVEL COSTS  ON WASTEWATER FLOW BASIS
U)

Annual
Industry
Category
and Treatment Level
Category
Treatment
Treatment
Category
Treatment
Treatment
Category
Treatment
Treatment
Category
Treatment
Treatment
I:
Level
Level
II:
Level
Level
III:
Level
Level
IV:
Level
Level

1
2

1
2

1
2

1
2
Investment
($ per gpm)

600
737

600
737

285.29
294.12

16.54
119
Costs ($ per 1,000 gal.)
Operating Cost
Capital

0
0

0
0

o
0

0
0

.057
.070

.057
.070

.027
.028.

.0016
.013
Depreciation

0.
0.

0.
0.

0.
0.

0.
0.

076
094

076
094

036
038

0021
017
less Power

0
0

0
0

o
0

0
0

.336
.413

.336
.413

.033
.033


.240
Power

0.007
0.008

O.OG7
0. 006

0 I ' ' «i
0.004

0
0.011
Total

0.476
0.585

0.476
C.J35

100
0.103

0.004
0.281

-------
                                                  Table  99 .
                                    SCRUBBER COSTS vs. FABRIC FILTER COSTS
                                          FOR AIR POLLUTION CONTROL
                                 ON 30 mw OPEN ELECTRIC SUBMERGED-ARC FURNACES
                                               SCRUBBER SYSTEM
ui
00
         HC Ferromanganese
         S ilicotnariganese
         HC'' Ferrochromium
         50% Ferrosilicon
         HC Ferromang'anese
         Silicomanganese
         HC Ferrochromium
         50% Ferrosilicon
Investment
$

1,640,000
1,640-, COO
1,472,000
3,180,000

<$ / p .. .T
V / -U.vv
54,667
54,667
49,067
106,000
FABRIC FILTER
Investment
$
1,640,000
1,640,000
1,190,000
2,340,000

S/isw
54,667
54,667
39,667
78,000
Annual
$

826,000
8 2 6, COO
699,000
1,986,000
SYSTEM ,
A-.r.v.?.l
	 $
445,000
445,000
335,000
734,000
Costs
'• /
* / • '. . i : •_
3.49
4.29
2.83
?. r*

Costs
£/--•:-.:•
1.8B
2.31
1.56
2.9A

S/ton

8.37
13. S3
11.87
39.72


$/ton
4.51
1C. 17
6.54
14.68

-------
Figures 18 -through 21 show the relative costs of treatment for reduction
of effluent volumes and loads of the most critical pollutants  from  the
raw  wastes  before  any  treatment  processes  other than recirculation
and/or \water conservation methods.  The  most  critical  pollutants  are
taken  as suspended solids for Categories I, II, and III; and heat loads
for Category IV.

The costs of Level 1 Treatments were equaled r.o unity ana tne  costs  of
the  other  Levels  expressed  as their costs relative to unity.  As the
curves show, more costly treatment do^s net necessarily result in volume
load reductions.

These curves provide graphical inicrmation of inter-st, out must be read
in the context of the previously uescribec Treatment  Levels  to  be  of
value.
                                  139

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                                      FIGURE 18.

                       COST OF TREATMENT vs. EFFLUENT REDUCTION
                                      CATEGORY I
         W
         •u
         03

         0
         3
         C
         C
         (D
         e
         j_i
         (0
         (U
         (J
         H

         eu
         >
         •H
         4->
         (fl
         rH
         0)
           3.0
           2.0
           1.0 ^=
                             % Effluent Volume Reduction
                          20        40       60         80
              99.0
    .      I

        99.5


Suspended Solids Reduction
  100
  O ft*
100.0
** Includes cost of  air  pollution control system.

-------
                             FIGURE   19.


              COST OF TREATMENT vs.  EFFLUENT REDUCTION
                            CATEGORY  II
   1.4
       0
CO

2  1.3
fl)
3
C
c
a  1.2
91
e
U
ca
H
0)
oi
   1.1
   1.0
      98
                      Effluent Volume  Reduction
20
         40
         ~r
.60
98.5         99           99.5


   % Suspended Solids  Reduction
._JJ)0
                                        100,

-------
                             - FIGURE   20.


               COST OF TREATMENT vs.  EFFLUENT  REDUCTION

                             CATEGORY  III
CO


CO


u
c
G
c

-------
                                                    FIGURE   21.


                                    COST OF  TREATMENT  vs.  EFFLUENT REDUCTION

                                                   CATEGORY IV
u»
                       •14.0
                       0)
                       o
                       o
                        12.0
                       3
                       B
                       « 8.Oh
                       %     !•
                       (0
                       0)
 20
"i
% Effluent Volume Reduction


                          80
    40
     i
60
 i
                                                                             100
                       «
                       iH
                       OJ
                         4.0 -
                         1.0
 I

 20
                  
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INCREMENTAL COSTS OF ACHIEVING LEVELS OF TREATMENT TECHNOLOGY

The  cost of achieving the various levels of treatment technology in the
industry will vary from piant-to-plant,  depending  upon  the  treatment
currently  in use.  The best estimates of these costs are given below by
Category, based  upon  the  assumed  levels  of  present  technology  in
"typical" plants.

Category I

The  "typical"  plant probably has a lagoon in which the scruober waste-
water is treated by plain sedimentation prior  to  discharge.   Although
this  'typical'  lagoon may be usable as part of a new treatment scheme,
it is likely that almost all of the costs shown in  Table  97  would  be
incurred to bring "the plant's effluent down to .the suggested limitation.
If the plant were to go to Level 2 from this base, it would require only
the  addition  of  .a  sand  filter  and  recirculation system, i.e., the
arithmetic difference in costs between Levels 1 and 2.   Therefore,  the
incremental  cost of reaching Level 1 would be $17,143/mw in investment,
and $0.859/mwhr in annual costs.  The incremental cost of reaching Level
2 would be $3,,920/mw for investment, and $0.197^mwhr in annual costs.

Category II

The "typical" plant probably has a lagoon in which  the  scruboer  waste
water  is treated by sedimentation and for destruction of cyanides prior
to discharge.  Again, it may be assumed that the cost of reaching  Level
1  is  100% of that shown, and the cost of reaching Level 2 from Level  1
is the  arithmetic  difference.   Therefore,  the  incremental  cost  of
reaching  Level  1 would be $22,222/mw in investment, and.$ 1.113/mwhr in
annual costs.  The additional costs to reach Level 2 woula be  i5,081/mw
in investment, and $0.255/mwhr in annual costs.

Category III                                             ~

The  "typical" plant again for this Category probably has a small lagoon
and would probably require expenditure of 100% of the costs shown, which
makes the incremental cost for Level 1 $2,526/tpd  for  investment,  and
$1.28/ton  for  annual  costs.   To  reach  Level  2  would  require  an
additional investment of $78/tpd, and increase annual costs by $0.03.

Category IV

The "typical" plant may be assumed to have  once-through  cooling  water
use  at  no  cost.   The  incremental  costs  to reach Level 1 Treatment
Technology would be $1,266 per mw for investment and $0.017 per mwhr for
total annual costs.  A cooling tower would be a wise  alternative  to   a
cooling  pond.   The incremental costs for a cooling tower system  (Level
2) would be $8,444 per mw for investment and $0.512 per mwhr for  annual
operating costs.


                                  144

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ENERGY AND NON-WATEF QUALITY ASPECTS

There  are  significant  energy  and  nonwar.er  quality  aspects  to the
selection and operation ot treatment systems.  These may  t>e  considered
as   land   requirements,   air  and  solid  wasts  aspects,  oy-product
            requirements,   air
potentials,  and energy requirements.

Land
One of the  most  important  aspects  in  the  selection  ot  wastewater
treatment  systems  in  this  industry  is the land required for cooling
ponds and water treatment systems.  Many plants  in  the  industry  have
extensive  land  areas  available  for  such  uses  and  may  elect this
generally lower cost treatment alternative.  Other plants  do  not  have
land  readily  available  and would have to select alt=rnatj.ve treatment
systems such as cooling towers rather than ponds and tnt use of  filters
for  sludge  dewatering,  rather  than  sludge  lagoons, for tnis reason
alone.

Air and Solid^Wastes

The solid waste produced by treatment of waste waters  in  the  industry
derives  principally  from  the  smelting  operation  as  waste from air
pollution control devices.  The solid waste from air pollution  controls
is  produced  whether a dry or wet system is utilized and varies only in
that the former produces a slurry or sludge, the  latter  a  fine  dust.
The  slurry  or sludge is generally accumulated in sludge lagoons, while
the dry dust may be bagged and landfilled or simply piled.  More careful
attention should be  directed  to  the  disposal  of  these  potentially
harmful  materials.   Possible  improvements  might  be iandfilling in a
sealed site, or encapsulation in concrete or polymers.  Tnere  has  been
little  success in efforts to agglomerate these solids for recharging to
the smelting furnaces, although it is probable that dry  dust  could  be
utilized more easily than wet sludge.

By-Product Potentials

In  the case of metals refining at one plant, a baghouse is to replace a
wet scrubber and the particulate matter is to be leached to produce  the
electrolyte  for  electrolytic  manganese production.  Trie potential for
such recovery methods is probably  very  limited,  since  this  refining
process  is  not a common operation.  The use of particulates in furnace
charges is not actually being done yet.

Slag concentration is used at a number of plants to recover metal values
and as a by product, to produce slag for sale or other use.  The sale or
use of slag varies from place to place.  In one  location  slag  can  be
readily  -sold  at  a  good  price,  since  stone must be imported from a
distance.  This is probably not a common situation.   At  another  plant
                                  145

-------
all  of  the  slag produced  is used on-site for road building.  At other
plants, markets or uses for  slag cannot be found.

By-product recovery in the   case  of  the  further  use  of  the  metals
refining  particulates reduces a solid waste problem and does nor add to
potential water pollution, since  the particulates"  replace  ore  in  an
electrolytic  process.   Slag  concentration  reduces  solid wastes, but
results in a water pollution potential not otherwise present.

Energy Requirements

The use of recirculation cooling water systems is primarily due to water
supply limitations.  Plants  that use well water  supplies  generally  do
not have enough water for once-through cooling systems.  Those which use
purchased  city water find that water costs favor recirculating systems.
One plant uses well water  and  recirculation  with  cooling  towers  in
preference  to  pumping  river water over a distance of almost one mile.
Those plants which  have  installed  facilities  for  thermal  pollution
abatement have used cooling  ponds.  In cases where land availability for
cooling  ponds  might  be  a problem, spray canals or cooling towers are
alternatives to cooling  ponds  for  thermal  pollution  abatement.   In
considering   alternative    thermal  pollution  abatement  methods,  the
relative energy requirements may be significant.

Power requirements for waste water treatment systems otiier than  cooling
towers  are generally low.   Power uses range from less than 0.1% to 1.3%
of the power used in the smelting furnaces.  The higher  figure  is  for
the  most  power-intensive   system  found  during the survey, which uses
clarifier-flocculators, sand filters, softening,  and  recirculation  of
process  water.   The  lower figure  is  for  a system using lagoons, a
clarifier-flocculater, and recirculation.  The  power  requirements  for
cooling  towers  reportedly  range up to about 1.8% of the power used in
the smelting furnaces.  Power requirements  for  the  use  of  the  most
power-intensive  treatment   systems  for process and cooling water could
thus amount to 3% of the power used in production.  This  compares  with
the  use  of  10%  of  the productive power for operation of high-energy
scrubbers for air pollution  control.  Based on pressure drops, the power
requirement for dry dust collectors is one-third or half that  for  high
energy scrubbers.
                                   146

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                               SECTION IX

        BEST PRACTICABLE CONTROL TECHNOLOGY CURRENTLY AVAILABLE,
                       GUIDELINES AND LIMITATIONS


INTRODUCTION

The  effluent  limitations which musr be achieved by July 1, 1977 are to
specify  the  degree  of  effluent  reduction  attainable  through   the
application   of  the  Best  Practicable  Control  Technology  Currently
Available.  This is  generally  based  upon  the  average  of  the  best
existing  plants  of  various  sizes, ages and unit processes within the
industrial category and/or subcategory.

Consideration must also be given to:

a.  The total cost of application  of  technology  in  relation  to  the
effluent reduction benefits to ce achieved from such application;

b.  the size and age of equipment and facilities involved;

c.  the processes employed;

d.   the  engineering  aspects  of  the  application of various types of
control techniques;

e.  process changes;

1".    non-water   quality   environmental   impact   (including   energy
requirements) .

Also, Best Practicable Control Technology Currently Available empnasizes
treatment  facilities at the end of a manufacturing process but includes
the control technologies within the process it.self when the  latter  are
considered to be normal practice within an industry.

A  further  consideration  is  the  degree  of  economic and engineering
reliability  which  must  be  established  for  the  tecnnology  to   be
"currently  available."   As  a  result of demonstration projects, pilot
plants and general use, there must exist a high degree or confidence  in
the  engineering  and  economic  practicability of the tecnnology at the
time of commencement of construction  or  installation  of  tne  control
facilities.


EFFLUENT   REDUCTION   ATTAINABLE   THROUGH   THE  APPLICATION  OF  BEST
PRACTICABLE CONTROL TECHNOLOGY CURRENTLY AVAILABLE  (BPCTCA)
                                  147

-------
Based upon the information  contained in Sections  III  tnrough  VIII  of
this  report,  a determination has been made that the degree of effluent
reduction attainable through the application  of  the  best  practicable
technology  currently  available  is  the  application  of the levels of
treatment described in Section VII as the Level I  tecnnologies  to  the
various industry categories as shown in Table 100.

Table 100.  BPCTCA EFFLUENT GUIDELINES TREATMENT BASIS
 Industry__CategorY_           	Treatment Basis	

         I                     Chemical treatment, clarifier-flocculators,
                               recirculatior. at the scrubber
         II                    Chemical treatment, clarifier-flocculators
         III                   Clarifier-flocculators
         IV                    Reduction of temperature rise
                               to  2.6°C (5°F)
Category I

New,  larger open  furnaces  have been equipped with high-energy scrubbers
when wet air pollution controls have been selected.  The  water  use  at
the  scrubber  is  high due  to the volume of the off-gases to be treated,
but the waste water effluent volume is reduced by recircuiation  at  the
scrubber  and  this   lowered volume is that to be treated for discharge.
The costs here would  be those given in Tables 97  and  98,  Category  I,
Treatment  Level 1.   The  alternative use of steam/hot water scrubbers or
electrostatic  precipitators  should  result  in  even  less  costs   if
treatment is for discharge, since waste water volumes would be less.

Although  the entire  treatment system is not presently in use at any one
plant, portions of the suggested technology as shown in  Figure  17  are
readily  transferable from other  plants  within  this  industry.   No
innovative or new  technology is involved - rather,  the  application  of
existing and fairly pedestrian technology to this industry's problem.

Category II

Covered   furnaces  have  generally  been  equipped  with  disintegrator
scrubbers in the past, although some of the newer furnaces are  equipped
with  high energy  scrubbers.  The volume to be treated for discharge was
taken as that of Plant B, sample point D.  As in Category I,  the  usage
of  steam/hot  water  scrubbers  should  significantly  reduce treatment
costs, since water volumes  would be less.


                                  148

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Although the technology  is not  in  use  at  any one  plant,  portions are  in
use at various  ferroalloys plants  and  should be readily  transferable.

Category III

The  loads attainable by the  use of  such  technology  described as Level 1
for this category are probably  as  good as could be expected if water  is
used  on  a  once-through  basis.    The.  technology  of clarification and
flocculation  is,  again,  rather  commonplace.    Other   methods   for
sedimentation    (such    as  lagoons)   might   be   used for  meeting  the
recommended guidelines,  if sufficient  land is available.   The  suggested
technology, however, minimizes  land  requirements.

Category IV

Cooling  ponds   are  in  present   use   in at least one ferroalloy plant,
installed for thermal pollution abatement when once-througii  cooling  is
used.   The  relatively  low  cost  can be justified en  tne basis of the
large reduction  (about 63%) of  the thermal load to  the   stream.   Where
land  is  not available  for cooling  por.os, spray  canals  (s^ray por.ds)  or
cooling towers  are alternatives.

Summary

The suggested   Guidelines  do  not  appear  to present   any  particular
problems  in  implementation.   The processes involved are all in present
use in ferroalloy plants, are common waste water  treatment  methods  and
no engineering  problems  are involved in design or construction.  Process
changes  are  not required in any  existing plants and the size or age of
facilities has  little or no  bearing   on  the applicability  of  these
.methods.

Some  additional solid  wastes are  generated by  the suggested treatment
methods since better treatment  than  is presently  practiced as  proposed.
Power  consumption  for  treatment  is about  1% of that  usea in the
furnaces.
The effluent limitations here apply to measurements taK«=n at the
of the last waste water treatment process unit.
                                                                   outlet
The effluent loads, together with  estimated costs  applicaole to the Best
Practicable   Control   Technology  Currently  Available  Guidelines  and
Limitations are  summarized in  Table  101.


APPLICATION OF LIMITATIONS

The  application  of  these  guidelines   and  performance  standards  to
specific  plants  is  intended to be  or.  the basis of a "building block."
                                   1U9

-------
approach to define the  effluent  limits   from  the   plant   as   a  whole.
Consider, for example,  a  ferroalloy plant with the  following processes:

30 mw open furnace with an  electrostatic  precipitator  with  water  sprays
20 mw open furnace with a baghouse
15 mw covered furnace with  a  scrubber
Slag concentrating, feed  rate 9.07 kkg  (10 tons)/hr
Exothermic smelting, producing 4.54 kkg  (5 tons)/day.

The  total  permissible  load of suspended solids would be  calculated by
Category as follows:

Category I:   (30 X 24)  mwhr/day X 0.352 Ibs/mwhr =  254 j.bs/day

Category II:  (15 X 24)  mwhr/day X 0.461 Ibs/mwhr =  166 Ibs/day
              5 ton/day X 3 X 0.461 Ib/ton product  = 7 lo/day

Category III: 10 tor./hr X 24  hr/day X 2.659  It/ton  processed =  638  Ib/day


Category IV:  24(30 + 15 + 16)  mwhr/day X  2.959 Ibs/mwhr=  4,620 Ibs/day

     Total plant load,  Ibs/day suspended  solids= 5,685 ibs/aay
                                                 (2,580 ky/day)
                                   150

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                                          Table  101.   BEST  PRACTICABLE  CONTROL TECHNOLOGY  CURRENTLY  AVAILABLE
                                                                GUIDELINES  AND LIMITATIONS
         CATEGORY I
 30 Day Average 24 hr Maximum
                        CATEGORY II
                30 Day Average  24 hr Maximum
                                         CATEGORY III
                                 30 Day Aver-  24 hr Max.
                                                                                                                       CATEGORY IV
                                                                                                               30 Day Average  24 hr Maximum
                  kg/mwhr  Ib/mwhr kg/nwhr  Ib/mwhr  kg/mwhr  Ib/mwhr  kg/mwhr  Ib/mwhr  kg/kkg Ib/ton kg/kkg Ib/ton kg/mwhr Ib/mwhr kg/mwhr Ib/mwhr
    Constituent	proc.   proc.   proc.   proc.	
Suspended Solids
Total Chromium
Hexavalent
Chromium
Total Cyanide
Manganese
Oil
Phenol
Phosphate
pH
.160
.0032

.0002

.032
.045
.0032
.0064

.352
.007

.0004

.070
.098
.007
.0141
6.0-9.0
.319
.006

.0006

.064
.064
.004
.013

.703
.014

.0014

.141
.141
.010
.028

0.209
0.004

0.0003
0.002
0.042
0.059
0.004
0.008

.461
0.009

0.0006
0.005
0.092
0.129
0.009
0.018
6.0-9.0
0.419
0.008

0.0008
0.004
0.084
0.084
0.006
0.017

0.922
0.018

0.0018
0.009
.184
0.184
0.013
0.037

1.330
0.026



0.266
0.372



2.659
0.053



0.532
0.745


6.0-9.0
2.659
0.053



0.532
0.532



5.319
.106



1.064
1.064



1.343
0.027

0.002


0.376

0.161

2.959
0.059

0.004


0.828

0.355
6.0-9
2.686
0.054

0.005


0.537

0.269
.0
5.917
0.118

0.012


1.183

0.592

                                                                                                               kg-cal/  BTU/
                                                                                                               mwhr    mwlir
                                                                                                            kg-cal/ BTU/
                                                                                                            r.iwhr    mwhr
Heat Content

  Cost Items
Investment
Capital Costs
Depreciation
Operating Costs
 Less Power
Power Ci-Sts
fot.il Operating
  Costs
                                                                                            149,000 592,000 298,000 1,184,000
 $/mw
17,143
_$/mwhr_

 0.103
 0.138
 0.606

 0.012
 0.859
 $/mw
22,222
$/mwhr

0.134
0.178
0.785

0.016
1.113
$/ton/day
 2,526
 $/ton

0.344
0.459
0.421

0.051
1.28
$/mw.
1,266
$/mwhr

0.007
0.010
0.0

0.0
0.017

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                               S1-.CTIOM X

           BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHI-c.V/ibL£.,
                       GUIDELINES AND LIMITATIONS


INTRODUCTION

The effluenr limitations which must be achieved by July 1, 1963  are  t.o
specify   the  degree  of  effluent  reduction  attainable  through  the
application of the Best  Available  Technology  Economically  Achievable
(BATEA).    BATEA  is  determined  by the very best control and treatment
Technology employed by a  specific  point  source  witnin  trie  industry
category  or  by  technology  which is readily transferable irora another
industrial process.

Consideration must also be given to:

a.  The age of equipment and facilities involved;

b.  the process employed;

c.  the engineering aspects of  the  application  of  various  types  of
control techniques;

d.  process changes;

e.   cost-  of  achieving  the  effluent  reduction  resulting  from  the
application of this level of technology;

f.    non-water   quality   environmental   impact    (including   energy
requirements).

Also,  Best  Available  Technology  Economically Achievable assesses the
availability of in-process controls as well as additional  treatment  at
the  end  of  a  production process.  In-process control options include
water re-user  alternative water  uses,  water  conservation,  by-product
recovery,  good housekeeping, and monitor and alarm systems.

A further consideration is the availability of plant  process changes and
control  techniques  up  to  and including "no discharge" of pollutants.
Costs for this level of control are to be the top-of-the-line of current
technology subject to engineering and economic feasibility.


EFFLUENT REDUCTION ATTAINABLE THROUGH THE APPLICATION OF £>hST  AVAILABLE
TECHNOLOGY ECONOMICALLY ACHIEVABLE  (BATEA)

Based  upon  the  information  contained in Sections  III through VIII of
this report, a determination has been made that the degree  of  effluent


                                  153

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reduction   attainable   througn    th-   at I'licarion   or   t/est   available
technology economically  achievable  is  r.i -:  £? plicsrion 01  tne   levels   of
treatment  described  in  Section VII  as; T.fvf.l  2  to  the various industry
categories as shown in Table  102.


Table 102.  BATEA  EFFLUENT GUIDELINES  TREATMENT BASIS
 _Industr%JC ategory

       I

       II

       III
       IV
Cht-.Hi2C£l *rva~.iTir.-r:t, clariiier-ilocculators,
Sc.r.d fii-r^rfe, ir-circuiation
cr.enucal rr<~-arn;-:r:t, clariiier-
iloccuia-crs, sand filters, recirculation
Prcce-sfe v»atir r-citculation
Cooling towers, r-rcircularion,
             tmcnt of t iowuown
These guidelines nave  been   sel
considerations and  assumptions.

Category I
                basis  or  tne  rollowing
The  effluent  load   reduction   above  Level   I   is  primarily due to the
effluent reduction attained through recircule-tion of tne scrubber water,
although some of the  reduction  is due to  lower   concentrations  in  the
effluent.   Portions   of   the technology described are in use at various
ferroalloys plants, and no new  or innovative  technology is required.

Consideration was given in Category I to  the replacement  of  existing
scrubbers  with  fabric  filter  collectors,   which would result in zero
discharge of pollutants.   However,  the large  investment  costs  required
(from  $1.19  to 2.34 million for a 30 mw furnace vs approximately $.632
million for a scrubber waste water treatment  system)  probably makes this
technology economically unachievable,  particularly  so  when  it  would
cause  the  premature  retirement  of  existing   air  pollution  control
systems.

Category II

Again, load reduction above Level I is due primarily to the reduction in
effluent  volume  attained  by   recirculation.  .  Althougn  Plant  C  was
achieving   97%  recirculation   of  the  scrubber  water,  this  high  a
proportion may not be feasible  for all plants and the  standard  was  so
selected.  As before, no  innovative technology is required.
                                   154

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  Category  III

  Since  water   is   used  only  as   a  transport  or cooliny medium in  slag
  processing, the quality of  recirculated  water  is of  importance   only  to
  the  extent  of its abrasiveness on valves  and  pumps.   Operation with  no
  water discharge,  i.e., complete recirculation and reuse  is  practiced  at
  least  at  one plant  .  The engineering problems are  trivial,  requiring
  only recirculation pumps and clarifier-flocculators  close   to   the   slag
  processing equipment.

  Category  IV

  Cooling   water recirculation and reuse is suggested  in Treatment Level 2
  as being  accomplished  by the use of cooling towers witn  treatment of the
  blowdown  for removal of chromates  or phosphates.  This level or effluent
  reduction could also be achieved through the use of  spray canals such  as
  are used  in some  electric   power   plants.    The costs  given   are   thus
  conservatively high   and   are  based upon  methods in  current  use.   Such
  technology is  straightforward and  readily available.

  Summary

  The   suggested    Guidelines   present    no   particular   problems    in
  implementation from   an  engineering  aspect   and   require no  process
  changes.  Water reuse  and good  housekeepina are  empnasized.    Age  of
  equipment and  facilities are of no particular  importance.

  No  additional solid wastes of significance are created by  the  suggested
  treatment methods.  Increased power consumption may  amount  to  as much  as
  3*1 of furnace  power in the  most energy intensive water treatment system.
  The effluent limitations here apply to measurements  taken at the outlet
  of  the last waste water treatment process  unit.  It is not judged to  be
  practical to require the treatment or ccntrol  of  runoff due   to storm
1  water  for  the   1983  standards for existing plants.   Sucri treatment  or
  control would  be  very  difficult to accomplish   in  older plants having
  many  years  of   accumulations of  slag,  collected airborne  particulates,
  etc.  Depending upon the geography of  a plant site   and   tne  acreage
  involved,  costs   would  vary  widely  from plant   to plant.   Some  such
  containment as earthen dikes around production  areas  could conceivably
  be  used.  In  one steel mill where it was proposed to  collect  runoff and
  treat the collected water in a lagoon, the  costs involved were  equal  to
  the total expenditures for  a minimum discharge  recirculation system.

  The  effluent  loads,  together  with estimated costs, applicable to the
  Best  Available   Technology  Economically  Achievable    Guidelines   are
  summarized in  Table 103.
                                    155

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APPLICATION OF LIMITATIONS

The  application  of  these  guidelines  and  performance  standards  to
specific plants is intended to be on the basis  of  a  "building  block"
approach  to  define the effluent limits from the plant as a wnole.  The
application is as illustrated under Best Practicable Control  Technology
Currently  Available  in  Section  IX,  except  that with Best Available
Technology Economically Achievable,  the  permissible  suspended  solids
load  for  the hypothetical plant would be 263 Ib/day* rather than 5,685
Ib/day.
                                   156

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                                             Table  103    BEST AVAILABLE  TECHNOLOGY  ECONOMICALLY ACHIEVABLE
                                                               GUIDELINES AND  LIMITATIONS
cn
                                        CATEGORY  I
                           30  Day  Average       24  hr Maximum
                           kg/mwhr  Ib/mwhr
Suspended Solids
Total Chromium
Hexavalent
  Chromium
Total Cyanide
Manganese
01;
Phenol
Phosphate
pH

Heat Content
                           .012      .026
                           .0004     .0009
                           ,00001    .00002
                    kg/mwhr  Ib/mwhr

                    .024     .052
                    .0008    .0017
                    .00002   .00004
.0039
.0055
.0002
.0001
.0086
.012
.0003
.0002
.008
.008
.0003
.0002
.017
.017
.0007
.0003
                                         6.0-9.0
                                                                        CATEGORY II
                                                            30 Day Average       24 hr Maximum
kg/mwhr
0.016
0.0005
0.00001
0.0003
0.005
0.007
0.0002
0.0001

Ib/mwhr
0.035
0.0012
0.00002
0.0006
0.012
0.016
0.0005
0.0002
6.0-9
kg/mwhr
0.032
0.001
0.00002
0.0005
0.011
0.011
0.0004
0.0002
.1)
Ib/mwhr
0.071
0.002
0.00005
0.001
0.023
0.023
0.0009
0.0005

                                                                                    CATEGORY  IV
                                                                       30  Day  Average       24 hr Maximum
                                                                       kg/mwhr  Ib/mwhr
                                                                       0.067     0.148
                                                                       0.001     0.003
                                                                       0.00003   0.00006
                                                                               kg/mwhr   Ib/mwhr

                                                                               0.134     0.296
                                                                               0.003     0.006
                                                                               0.00005   0.0001
0.019

0.004
0.041

0.009
    6.0-9.0
0.027

0.008
0.059

0.018
                                                                                                          kg-cal/  BTU/
                                                                                                          mwhr     mwhr	
                                                                                                          7,500    30,000     14,900   59.000
                                                                                                   kg-cal/  BTU/
                                                                                                   mwhr     mwhr
      Cost  Item

      Investment
      Capital Costs
      Depreciation
      Operating Costs
        Less Power
      Power Costs
      Total Operating
        Costs
                    $/mw

                    21,063
                                               $/mwhr
                                        0.127
                                        0.169

                                        0.745
                                        0.015

                                        1.056
                                        $/mw ,

                                        27,303
                                                   $/mwhr
                                                            0.165
                                                            0.219

                                                            0.965
                                                            0.019

                                                            1.368
                                                            $/mw

                                                            8,444
                                                                       $/mwhr
                                                                                           0.049
                                                                                           0.065

                                                                                           0.354
                                                                                           0.044

                                                                                           0.512
      Category  III:  No  discharge  of waste water  pollutants  to navigable waters.  Costs as shown in Table 97.

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                               SECTION XI

                    NEW SOURCE PERFORMANCE STANDARDS
                       AND PRETREATMENT STANDARDS


INTRODUCTION

The effluent limitations which must, be achieved by  new  sources,  i.e.,
any  source,  the  construction of which is started after publication of
new source performance standard regulations, are to specify  the  degree
of  treatment available through the use of improved production processes
and/or treatment techniques.  Alternative processes,  operating  methods
or other alternatives musr. be considered.  The end result j.s to identify
effluent  standards  achievable  through  the use of improved production
processes (as well as  ccnt.ro!  technology) .   A  further  determination
which  must  be  made  for  new source performance standard is whether a
standard permitting no discharge of pollutants is practicable.

Consideration must also be given tc:

     a.  The type of process employed and process changes;

     b.  operating methods;

     c.  batch as opposed to continuous operation;

     d.  use of alternative raw materials arid mixes of raw
         materials;

     e.  use of dry rather than wet processes;
         recovery of pollutants as by-products.
In  addition  to  recommending  new  source  performance  standards  and
effluent limitations covering discharges into waterways, constituents of
the  effluent  discharge  must be identified which would interfere with,
pass through or otherwise be  incompatible  with  a  well  designed  and
operated  publicly owed activated sludge or trickling riiter waste water
treatment plant.  A  determination  must  be  made  as  to  whether  the
introduction  of  such  pollutants  into  the  treatment plant should be
completely prohibited.


EFFLUENT REDUCTION ATTAINABLE THROUGH  THE  APPLICATION  OF  NEW  SOURCE
PERFORMANCE STANDARDS


Based upon the information contained in Section III through VIII of this
report,  a  determination  has  been  made  that  the degree of effluent


                                  159

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reduction attainable by new sources is the same achieved by  application
of  the levels of treatment described in section X and/or the attainment
of zero discharge of waterborne pollutants to navigable  waters  in  the
various industry categories as shown in Table 104.


Table 104.   NEW SOUF.CE PERFORMANCE STANDARDS tASIS
 .Indus try_Cat^cjory._     	Treatment Pa sis	
         I              Baghouse for Air Pollution Control
         II             Chemical treatment, ciarifier -
                        flocculatcrs, sand filters, recalculation.
         Ill            Process water recircularion
         IV             Pecirculation through cooling towers,
                        chemical treatment of blowdown
       performance  standards  have  teen  selected  on the basis of the
following assumptions and considerations.

Category I

Baghouses on open furnaces achieve air  pollution  abatement  levels  at
least  as good or better than these of scrubbers and, or course, produce
no waste water effluents.  Industry representatives indicated during the
study that this is the method of choice in the face  of  more  stringent
effluent  quality  limitations  than  were previously in effect when wet
scrubbers have been  selected..   No  significant  engineering  or  other
technical problems are involved; this technology is state-c£-tne-art and
is  in wide use in the industry.  In fact, it is more common to equip an
open furnace with a baghouse than with a  scrubber.   Additionally,  the
annual  costs  for  a  fabric  filter  system  are about half tnose of a
scrubber system with waste water treatment, and the  power  requirements
are half or less those for a high energy scrubber.

Category II

Although  the  possibility  remains  of  developing  baghouses which are
explosion-proof and thus applicable to covered furnaces,  it  is  by  no
means  clear  that  this  is a practical alternative.  There is one such
baghouse on a covered furnace in the  world,  but  none  in  the  United
States.   One  other furnace utilizes a "candle filter"  (ceramic filter)
for dry cleaning of CO gas.  At this time,  and  with  only  two  closed
furnaces in the world so equipped, it does not seem practical to require
the use of a dry dust collection system.  Therefore, the treatment level
                                   160

-------
specified  tor EATEA, Category II appears to te t.riat wnj.cn will minimize
waste discharge.

Category III

Since the treatment level specified  for  BATEA  is  zc.ro  discharge  of
pollutants,  this  is the n=w source performance standard.

Category IV

Recirculation  of  cooling  water  through  cooling towers or tne use of
spray canals as specified  for  BATE A  is  T. he  only  clearly  available
technology.   The  possibility of using dry cooling towers exist.  Since a
dry  cooling  tower does not evaporate any of The cooled water, tnere is
no concentration  effect and no blowdown is necessary.  however, tne cost
of such systems as would be required in this industry is  sucn  tnat  it
would  probably  be  unfeasible.   Dry  cooling  towers are not a likely
alternative unless specified for industry generally ana  thus  available
readily  from equipment manufactures.  Th-r- BATFA treatment has thus been
selected as the basis for limitations from new sources.

SUMMARY

The suggested new source performance standards  consider  tne  means  by
which  no  discharge of waterfcorne pollutants to navigable waters can be
achieved.  Such "no discharge" standards are  clearly  available  for  2
categories  (I  and III) and are so specified.  Standards of perrormance
for the other  two  categories  are  those  which  will  minimize  waste
discharge.

The effluent loads, together with estimated costs, applicable to the New
Source Performance Standards are summarized in Table 105.

For  the  new  source,  performance  standards, it should be additionally
specified that all  measurements  taker:  for  purposes  of  meeting  the
effluent  limits   should be at the plant outfall, if the new source is a
new plant.  This  means, in effect, that run-oft from materials  handling
and  storage,   slag piles, collected air borne particulates, and general
plant areas must  be collected and treated or that storm water  must  not
initially contact such sources of pollutants.  Such control measures can
rather  easily  be built into new plants, but would be very difficult to
accomplish in older plants, having many years of accumulation  of  slag,
collected  airborne particulates, etc.  Practical control measures might
include impoundment of storm water and use of such water  as  an  intake
source or landfill of waste particulates.  The option of treating runoff
to  meet  the  effluent standard would, of course, be available.  If the
new source is part of an already existing plant, i.e.,  a  new  furnace,
all  measurements  should  be taken after the last waste water treatment
process unit.   These standards should te applied by the "building block"
approach, as discussed in section IX.  If the hypothetical plant of that


                                  161

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section were a new source, the permissible  suspended  solids  discharge
would be 244 Ib/day.

PRETREATMENT STANDARDS

The pretreatment standards under section 307(c) of the Act, for a source
within the ferroalloy industry which is an industrial user of a publicly
owned  treatment  works   (and  which  would  be  a new source subject to
section 306 of the Act, if it were to discharge  to  navigaole  waters) ,
shall  be  the  standard  set forth in Part 128, 40 CFk, except that the
pretreatment standard for incompatible pollutants shall be the  standard
of  performance  for  new  sources of that subcategory.  If tne publicly
owned treatment works is committed, in its MPDES  permit,  to  remove  a
specified  percentage  of  any  incomeatitle pollutant, the pretreatment
standard  applicable  to  users  of  such  treatment  works   snail   be
correspondingly reduced for that pollutant.
                                   162

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                                                      Table  105   NEW SOURCE  PERFORMANCE  STANDARDS
CTi
U)
Suspended Solids
Total Chromium
Hexavalent
Chromium
Total Cyanide
Manganese
Oil
Phenol
Phosphate
PH
0.016
0.0005

0.00001
0.0003
0.005
0.007
0.0002
0.0001

0.035
0.0012

0.00002
0.0006
0.012
0.016
0.0005
0.0002
6
                                        CATEGORY  II
                             30 Day Average       24  hr Maximum
                           kg/mwhr   Ib/mwhr    kg/mwhr   Ib/mwhr
                                                0.032
                                                0.001
                             0.071
                             0.002
                                                0.00002   0.00005
                                                0.0005
                                                0.011
                                                0.011
                                                O.OG04
                                                0.0002
                                           6.0-9.0
                             0.001
                             0.023
                             0.023
                             0.0009
                             0.0005
                                                    CATEGORY IV
                                         30 Day Average      24 hr Maximum
                                        kg/mwhrIb/rowhr
                                        kg/mwhr  lb/r.iwhr
                    0.067
                    0.001
         0.148
         0.003
0.134
0.003
0.296
0.006
                                        0.00003  0.00006
                                        0.00005  0.0001


                                                 0.059

                                                 0.018
                                                                    kg-cal/   BTU/        kg-cal/   BTU/
                                                                    mwhr      mwhr        mwhr      mw'nr
                                                                    7,500    30,000     T579UU~   59,000
0.019
0.004
0.041
0.009
6
0.027
0.008
.0-9.0
       Cost Item

       Investment
       Capital costs
       Depreciation
       Operating Costs
         Less Power
       Power Costs
       Total Operating
         Costs
$/mw

27,303
$/mwhr
                    0.165
                    0.219

                    0.965
                    0.019

                    1.368
$/mw

8,444
$/mwhr
                                        0.049
                                        0.065

                                        0.354
                                        0.044

                                        0.512
        Categories I and III:  No discharge o$ waste water pollutants to navigable waters.  Costs as shown in Table 97 and 99.

-------
                              SECTION XII

                            ACKNOWLEDGEMENTS

The  Environmental Protection Agency would like to thank Dr. h.C. Bramer
and Messrs. E. Shapiro and N. Elliott cf Datagraphics,  Inc.  for  their
aid  in  the  preparation  of this report.  Thanks are also given to the
sampling crews (Messrs. D. Bramer, D. Riston, C. Casweii, E. D.  Escher,
E. Brunell, et al) .  Special thanks is also given to Ms. Darlene Speight
of Datagraphics,  Inc.  and Mrs. Nancy Zrubek ot EPA for tneir long, late
hours spent in the typing and retyping of this report.

The author would like to thank her associates in the Erfluent Guidelines
Division,  particularly Messrs. Edward Dulaney, Wa.lter J. hunt, Ernst P.
Hall, and Allen Cywin for their helpful suggestions and assistance.

Thanks also are expressed to Messrs. George  A.  Watson  and  Archur  M.
Killan of the Ferroalloys Association for their valuable assistance.

Acknowledgement  and  appreciation is extended to those personnel of the
industry who cooperated in  plant  visitations  and  supplying  of  data
including  Dr.  R.A.  Person, Dr. C.R. Allenbach and Messrs. R. Bilstein
and J.E. Banasik of Union Carbide Corporation;  L.C.  Wintersteen,  W.A.
Moore,  and  L.A.  Davis  of  Airco,  Inc.; F.D. Turner ana W.A. Witt of
Chromium Mining and Smelting Corporation; C.G. Adler and £.W.  Batchelor
of  Foote  Mineral Company; F. Krikau and J.C. dine of Interlake, Inc.;
and C.F. Seybold, M. Evans, and L. Risi of Shieldalloy.

Appreciation is also  expressed  to  Mr.  H.  Fathman  wno  acted  as  a
consultant  to  Datagraphics, Inc. and provided invaluaole assistance in
preparation of this report.

Thanks are also given to Messrs. K. Durkee and J.O. Dealey of the Office
of Air Programs,  EPA, for their assistance during  the  course  of  this
study.

Thanks  are  also given to the members cf the EPA Working Group/Steering
Committee for  their  advice  and  assistance.   They  are:  Messrs.  A.
Brueckmann,  S. Davis, M. Dick, T. Powers, P.. Zener, E. Lazar and Dr. H.
Durham.
                                  165

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                              SECTION XIII
1.   Compilation of Air Pollutant Emission Factors,  U.S.    Environmental
Protection  Agency, Office of Air Prcqr ams , February, ±^12  (N.T.I.S. No.
PB-209 559) .

2.   Sherman, P. R. & Springman, E. P., "Operating   Proolems   witn   High
Energy  Wet  Scrubbers  on Submerged Arc Furnaces",  a paper presented at
the American  Institute  of  Metallurgical  Engineers  hiectric   Furnace
Conference,  Chicago, Illinois December, 1972

3.    Scherrer,  R.  E. ,  "Air  Pollution  Control for a Calcium  Carbide
Furnace", A.I.M.E. Electric Furnace  Ircc~--dir.gs,  Volume   27,  Detroit,
1969, pages 93-98

4.    Seybold,  Charles  F. ,  "Pollution  control Equipment, for Tnermite
Smelting Processes", A.I.M.E. Electric Furnace Proceedings,  Volume  27,
Detroit, 1969, pages 99-108

5.    Person,  R.  A.,  "Control  of  Emissions  from Ferroalloy  Furnace
Processing", A.I.M.E. Electric Furnacf Proceedings,  Volume  27,   Detroit.
1969, pages 81-92

6.    Fetelsdorf,  H. J. , Hodapp, E. , & Enciell, N. ,  "Experiences  with an
Electric Filter Dust  Collecting  System  ir.  Connection  with a 20-MW
Silicochromium  Furnace",  A.I.M.E. Elec-ric Furnace Proceedings, Volume
27, Detroit, 1969, pages 109-114.

7.   Gamroth, R. R., "Operation of 30,000 - KW Submerged Arc Furnace on
Silicomanganese",  A.I.M.E.  Electric  Furnace  Proceedings,   Volume 27,
Detroit, 1969, pages 164-166

8.   Dehuf f , J. A., Coppolecchia, V. D,, & Lesr.ewich, A., "The Structure
of Ferrosilicon" , A.I.M.E. Electric Furnace Proceedings.

9.   "Annual Statistical Report - American Iron and  Steel  Institute   -
1970", A. I.S.I., Washington, D. C. 80 pages

10.   "  1967  Census of Manufactures - Blast Furnaces, Steel  WorKS, and
Rolling and Finishing Mills", U. S. Department of  Commerce,   Bureau of
the Census,  MC67  (2) - 33A, 48 pages

11.    Elyutin,  V.  P.,  et  al  "Production  of  Ferroalloys Electro-
metallurgy",  Translated  from  Russian  by  the  Israel    Program   for
Scientific Translations, U. S. Department of Commerce,
                                  167

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12.   "Water  Use  in  Manufacturing",  1967 Ctrsus of .'Icaiuractures, U.S.
Department of Commerce,  Bureau of  the Census, Mr. 67  (1)  -7, April, 1971,
361 pages.

13.  Ferrari, Renzo, "Experiences  in Developing an   Efrective  Pollution
Control System for a Submerged Arc Ferrcally Furnace Operation", Journal
of	Metals, April, 1968,  pp.  95-104.

14.   "Statement  for  Relief  from  Excessive  Imports" The Ferroalloys
Association, Washington,  D. C. 1973, 15 pages.

15.  Communications with  Mr.  Edwin I. Kissmaii  of  General  Technologies
Corporation - Trip Peport from the Astafcula, OKio plant,  oi Union Carbide
Corporation, February  14,  1973.

16.   Braaten,  O.  and   Sandberg,  C.,   "Progress   in   Electric Furnace
Smelting of Calcium Carbide and  Ferroalloys", 5rh International Congress
on Electro-Heat, 7 pages.

17.  Scott, J. W. , "Design of a  .35,000  F.  V*.  High  Caroon  Ferrochrome
Furnace  Equipped with an Electrostatic i'recipitotor", Tne Metallurgical
Society of A.I.M.E., pap^.r No. EFC-2, 9 pag<-s.

18.  "A Study of Pollution Control Prc.crices in Manufacturing Industries
- Part 1 - Water Pollution Control", Lun 5 bradstreer.. Inc., June, 1971.

19.  Blackmore, Samuel S., "Dust Emission Control Program Union  Carbide
Corporation  Metals  Division",  Air Pollution Control Association, 57th
Annual Meeting, June 21-25, 1964,  16 pages.

20.  "Control Techniques  for  Emissions  Containing  Chromium,  Manganese,
Nickel,  and  Vanadium" Office of  Air Programs, Environmental Protection
Agency, January 12, 1973.

21.  Mantell, C. L.,   "Electrochemical   Engineering,"  McGraw-Hill  Book
Company, Inc., 4the Edition,  1960, pages 468-533.

22.   Person,  R.  A.,   "Emission  Control of Ferroalloy  Furnaces," Paper
presented  at  the  4th   Annual  North   Eastern  Regional  Antipollution
Conference, July 13-15,  1971, 30 pages.

23.   Smith,  Robert   &   McMichael,  Matter  F.,  "Cost  and Performance
Estimates for Tertiary Wastewater  Treating  Processes" -,  United  States
Dept. of Interior, Federal Water Pollution Control Administration, June,
1969, 27 pages.


24.   "Pretreatment Guidelines for the  Discharge of  Industrial Wastes to
Municipal Treatment.Works", Environmental Protection  Agency,  November
17, 1972, Draft Report.


                                   168

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25.   "Minerals  Yearbook  - 1970", United States Bureau or Mines,  pages
513-518.

26.  "Minerals Yearbook - 1967", United States Bureau  or  i>iines,   pages
499-506.

27.   "A  New  Process  for  Cleaning and Pumping Industrial Gases  - The
ADTEC System", Aronetics, Inc., Tullahcma, Tennessee, 22 pages.

28.  "Cleanup in Our Ferroalloy Plants", Union Carbide World, July  1972,
Vol. 5, No. 3, 16 pages.

30.  "Annual Statistical Report - American Iron and  Steel  Institute
1972, A.I.S.I., Washington, D. C. pages U5-51.

31.  Eckenfelder, W. W., "Water Quality Engineerings, Barenes and Noble,
New York (1970) .

32.  "Air Pollution Control Engineering and Cost Study or" tne Ferroalloy
Industry"  (Draft  Report), 1973, U. S. Environmental Protection Agency,
Office of Air and Water Programs, Washing-ccn, D.C.
                                  169

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                              SECTION XIV

                                GLOSSARY


Blocking chrome - A high 10-12 % silicon grade of HC Ferrocnromium, used
as an additive in the making of chromium steel where it 'blocks'   (i.e.,
stops)  the reaction in the ladle.

Charcje __ Chrome - A grade of HC ferrochromium, so called because it forms
part of the charge in the making of stainless steel.
Chrome ore - lime melt_   A melt of chromium ore and lime produced in an
open   arc   furnace  and  an  intermediate  in  the  production  of  -LC
f errochromium.

Cover ed_ furnace - An electric furnace with a water-cooled cover over the
top to limit the introduction of air which would burn tne gases from the
reduction process.   The furnace  may  have  sleeves  at  the  electrodes
(fixed  seals  or  sealed  furnaces)  with the charge introduced through
ports in the furnace cover, or the  charge  may  be  introduced  through
annular  spaces  surrounding  the  electrodes   (mix seals or semi-closed
furnace) .

Exothermic Process - Silicon or aluminum, or a combination of  the  two,
combine  with  oxygen  of  the  charge, generating considerable heat and
creating temperatures  of  several  thousand  degrees  in  the  reaction
vessel.  The process is generally used to produce high grade alloys with
low carbon content.

Ferroalloy  -  An  intermediate  material,  used as an addition agent or
charge  material  in  the  production  of  steel   and   other   metals.
Historically,  these  materials were ferrous alloys, hence the name.  In
modern usage, however,  the  term  has  been  broadened  to  cover  such
materials  as  silicon  metal, which are produced in a manner similar to
that used in the production of ferroalloys.

Induction .furnace  -  Induction  heating  is  obtained  by  inducing  an
electric current in the charge and may be considered as operating on the
transformer  principle.   Induction furnaces, which may be low frequency
or high frequency,  are used  to  produce  small  tonnages  of  specialty
alloys through remelting of the required constituents.

Open furnace - An electric submerged-arc furnace with the surface of the
charge  exposed to the atmosphere, whereby the reaction gases are burned
by the inrushing air.
                                  171

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Open^arc_furnace - Hear is generated in  an  open  arc  furnace  by  the
passage  of electric arc either between two electrodes or oetween one or
more electrodes and the charge.  The arc furnace consists of  a  furnace
chamber  and  two  or more electrodes.  The furnace chamber nas a lining
which can withstand the operating temperatures and which is suitable for
the material to be heated.  The lining is contained within a steel shell
which, in most cases, can be tilted or moved.

Pre-baked electrodes - An electrode purchased in finished form available
in diameters up to about 130 cm (51  in.) .   These  electrodes  come  in
sections with threaded ends, and are added to the electroae column.

Reducing  Agent - Carbon bearing materials, such as metallurigical coke,
low volatile coal, and petroleum coke used in the  electric  furnace  to
provide  the  carbon  which  combines  with oxygen in the charge to form
carbon monoxide, thereby reducing the oxide to the metallic form.

Self-baking electrode - The electode consists cf a  sheet  steel  casing
filled  with a paste of carbonaceous material quite similar to that used
to make prebaked amorphous carbon electrodes.  The heat from the passage
of current within the electrode and the heat from  the  turnace  itself,
volatilize  the  asphaltic  or  tar  binders in the paste to make a hard
baked electrode.

Sintering - The formation of larger particles,  cakes,  or  masses  from
small  particles  by  heating alone, cr by heating and pressing, so that
certain constituents of the particles coalesce, fuse, or otnerwise  bind
together.   This  may  occur  in  the  furnace itself, in wnich case the
charge must be stoked to break up the agglomeration.

Steam/hot water^scrubber -  A  system  for  removing  particulates  from
furnace  gases,  where  water  is first heated by the gases to partially
form steam, and then intimately contacted with  the  dirty  gases.   The
scrubber  water  containing  the particulates is then separated from the
cleaned gases, which are emitted to  the  atmosphere.   This  system  is
characterized by a low water usage and pressure drop.

Stoking  - The stirring up of the upper portion of the charged materials
in the furnace.  This loosens the charge and allows free upward flow  of
furnace gases.

Submerged-arc furnace - In ferroalloy reduction furnaces, the electrodes
usually  extend  to  a  considerable  depth  into the charge, hence such
furnaces are called "submerged-arc furnaces".  This name is used for the
furnaces whose load is practically entirely of the resistant type.

Tapping - This term is used in  the  metallurgical  industries  for  the
removal  of  molten  metal  from  furnaces, usually by opening a taphole
located in the lower portion of the furnace vessel.
                                   172

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Vacuum furnace - A furnace in which the charge  can  te  brought  to   an
elevated  temperature  in  a  high  vacuum.   The high vacuum provides  an
almost completely inert enclosure where the   process  or   reduction and
sintering can occur.
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                              SUPPLEMENT A

                 CONSULTATIONS AND PUBLIC PARTICIPATION

Scope of_Consultations

Prior  to  the  publication of the Development Document arid  the  proposed
regulations for the ferroalloy  manufacturing  industry,   the  following
agencies,  groups,  and  corporations  were  given  the   opportunity  to
comment:

1.A11 State and U.S. Territory Pollution Control Agencies.

2.Ohio River Valley Sanitation Commissicr:.

3.New England Interstate Water Pollution Control commission.

U.Hudson  River Sloop Restoration, Inc.

5.Conservation Foundation.

6.Businessmen for the Public Interest.

7.Environmental Defense Fund, Inc.

8.Natural Resources Defense Council.

9.The American Society of Civil Engineers.

10.Water  Pollution Control Federation.

11.National Wildlife Federation.

12.The American Society of Mechanical Engineers.

13.Department of Commerce.

14. Water  Resources Council.

15.Department of the Interior.

16.U.S. Department of the Treasury.

17.The Ferroalloys Association.

18.Effluent Standards and Water Quality Information Committee.
                                  175

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Industry Participation

No interim permit guidance had  teen  ic?!rued  for  this  industry  and  initial
contact with representatives  of the  industry war.  made  in  late  February,
1973.

Plant visitations and sampling  was conducted during  Maren,  April  and May
of   1973.   The  contractor's  draft   rsporr   was   distributed  to   The
Ferroalloys Assocication and  they were  ask-rd '-o  comment  on   the draft
report  by  August  1, 1973.   Comments  troni  six  of the  companies affected
and the trade association were  received by  AuciuFt 20,  1973.

1. Various members of industry quesT.icr.ea The  r ~-..juir ement  o±  ary   dust
collectors  for  new  sources oi oper.  •el^ctrir  furnaces.  Tney contended
that usage of certain raw materials  (high  in   chloriaes,   fluorides  or
sulfur)  would require the use  of a  scrubber £cr  effective  air pollution
abatement.  To the  best of our  knowledge tre.s--  raw  materials are   not
presently  in  use,  and  th-~  proposed standard  is  valia.  It should be
recognized that these- standards will r e sub jf ct to periodic review,   and
should such raw materials come  iivcc  utv:, this {[articular  standard might,
of course, be subject to revisior..

2.Some   industry   representatives    conter.ded  that  tne  contractor's
recommended limitations and standards  were  restrictive as  to product.
The  proposed  limitations and  standards r>ow allow for production of any
product.

3.Some industry representatives requested that  once-tnrougn   noncontact
ccoling  water  be  exempted  from   any  limitations.   Due to the large
quantities of heat  which can  be discharged  from this source,  it is   felt
reasonable to limit such therrral pollution.

Industry,  under  Section  316  of the  Act,  can  be granted less stringent
limitations for nonccntact cooling waters if it can  be demonstrated   "to
the  satisfaction   of  the  Administrator  that  any effluent limitation
proposed for the control of the thermal component of any  discharge   from
such  source  will  require   effluent   limitations   more  stringent  than
necessary to assure the  protection  and  propagation of  a  balanced,"
indigenous  population  of  shellfish,   fish, and wildlife  in and on the
body  of  water  into  which  the  discharge  is  to  oe  made."     "The
Administrator  may  impose an  effluent  limitation  under such sections for
such plant, with respect to the thermal component with   such  discharge
(taking  into  account  the   interaction of such thermal component  with
other pollutants),  that will  assure  the protection and propagation of  a
balanced,  indigenous population of  shellfish,  fish, and  wildlife.in and
on that body of water."

4.Some industry  representatives  requested that the limitations   and
standards  take  into account dissolved solids  levels. Although  certain
dissolved solids such as  calcium  and  magnesium may present  scaling


                                  176

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problems,  these  can  be  controlled by softening.  One  plant, nowever,
recirculated 97 percent of its scrubber waste water after treatment,  the
only blowdown being from  the  clarifier  underflow.   A  uiast   furnace
producing ferromanganese which was studied as part cf the iron and  Steel
industry  study  had  a  closed  recycle  system for gas  scrubuer water.
Dissolved solids levels were 70,bOC tc  82,300  mg/i  .in  the  clarifier
overflow, with potassium levels of 24,000 -*-o 25,600 mg/i.   If tnat  blast
furnace  system  can operate successfully at those levels,  this industry
should be able to operate at a level cf about 8,000 mq/i  potassium.

Eff_luent Standards and  Water  Quality  lBl^2iHl2iA2Ii  B^visory_  Committee
Comments


Concern  was  expressed  about  th-i  lack  cf  adequate   existing  waste
treatment plants, in the industry, and trie Coiwnitt.e  ot/servea  that   the
normal  practice  of  determining  best  practicable t=cnnology and best
available technology is not entirely applicable  (in  sucn   case) .    The
best practicable and best available technology base:s nave been reviewed,
and  the  conclusion  reached  that  although no one pla^t  is capable of
reaching  environmentally  acceptable  levels  rcr  all   parameters,   an
amalgamation  of  the  treatments  at the plar.ts studied  could meet  such
levels.

Other Federal Agencies

The Department of the Interior commented that, the costs of  treatment  do
not  appear  to  include  costs  for  monitoring.   This  is quite  true,
however, these costs would be incurred no matter which treatment  method
was used.

The  Department of Commerce suggested that the guidelines i>e issued as a
range of numbers (because of variations ir plar.ts, climates, etc.).    No
climatic  variations  were found, except for thermal, and this variation
has been taken into account in the proposed guidelines.   Variations  in
plants  have been allowed for — both by the building block approach and
by setting the guidelines to  permit  production  of  ail  alloys.    For
example,  a  plant  producing  manganese  products  will  have no  problem
meeting  the  guideline  for  chromium,  and  a  chromium  plant  should
experience no difficulty with the regulation for manganese.

Public Interest Groups

The comments received from public interest groups were noncommittal.

Period for Additional_Cornments

Upon  publication  of  the proposed regulations, interested persons will
have 21 days in which to comment on the proposed regulations.
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