EPA-440/ 1-75/037
GROUP I, PHASE II
Development Document for Interim
Final Effluent Limitations Guidelines
and Proposed New Source
Performance Standards
for the
SIGNIFICANT INORGANIC PRODUCTS
Segment of the
INORGANIC CHEMICALS MANUFACTURING
Point Source Category
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
May 1975
-------
DEVELOPMENT DOCUMENT
for
INTERIM FINAL AND PROPOSED EFFLUENT
LIMITATIONS GUIDELINES
and
PROPOSED NEW SOURCE PERFORMANCE STANDARDS
for the
SIGNIFICANT INORGANIC PRODUCTS
SEGMENT OF THE INORGANIC CHEMICALS MANUFACTURING
POINT SOURCE CATEGORY
Russell Train
Administrator
James L. Agee
Assistant Administrator for Water
and Hazardous Materials
Allen Cywin
Director, Effluent Guidelines Division
Elwood E. Martin
Project Officer
May 1975
Effluent Guidelines Division
Office of Water and Hazardous Materials
U.S. Environmental Protection Agency
Washington, D. C. 20460
-. ^'i^nfhC:^! r--ot3ction Agency
" '•
- - -j.-^rr; treet
Chicago, Illinois 60504
-------
U,S. Eny;rG!inTjrrai Protection Agency
-------
ABSTRACT
This docjment presents the findings of an extensive study of
selected inorganic chemicals for the purpose of developing
effluent limitations guidelines for existing point sources
and standards of performance and pretreatment standards for
new sources, to implement Sections 304, 306 and 307 of the
Federal Water Pollution Control Act, as amended (33 U.S.C.
1551, 1314, and 1316, 86 Stat. 816 et. seq.) (the "Act").
Effluent limitations guidelines contained herein set forth
the degree of effluent reduction attainaole through the
application of the best practicable control technology
currently available (BPCTCA) and the degree of effluent
reduction attainable through the application of the best
available technology economically achievable (BATEA) which
must be achieved by existing point sources by July 1, 1977
and July 1, 1983, respectively. The standards of
performance and pretreatment standards for, new sources
contained herein set forth the degree of effluent reduction
which is achievable through the application of the best
available demonstrated control technology, processes,
operating methods, or other alternatives.
Supporting data and rationale for development of the
proposed effluent limitations guidelines and standards of
performance are contained in this report.
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CONTENTS
Section
I Conclusions \
II Recommendations 3
III Introduction 7
Purpose and Authority 7
Summary of Methods used for Development
of Effluent Limitations Guidelines
and Standards of Performance 8
General Description of Industry by
Product 12
IV Industry Categorization 35
Introduction 35
Industry Categories 35
Factors Considered 35
V Water Use and Waste Characterization 41
Introduction 41
Analytical Laboratory Wastes 41
Specific Water Uses 41
Process Waste Characterization 45
VI Selection of Pollutant Parameters 181
Introduction 181
Significance and Rationale for Selection
of Pollution Parameters 181
Significance and Rationale for Rejection
of Pollution Parameters 193
VII Control and Treatment Technology 197
Introduction 197
General Methods for Control and
Treatment Practices 199
VIII Cost, Energy, and Non-Water Quality Aspects 219
Cost and Reduction Benefits of
Treatment and Control Technologies 219
Summary 219
Individual chemical wastewater Treat-
ment and Disposal Costs 223
11
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IX Effluent Reduction Attainable Through
tne Application of the Best Practicable
Control Technology Currently Available 257
General Water Guidelines 258
Process Wastewater Guidelines and
Limitations for the Significant
Inorganic Chemicals Point Source
Subcategories 258
X Effluent Reduction Attainable Through
the Application of the Best Available
Technology Economically Achievable 3Q5
General Water Guidelines 306
Process Wastewater Guidelines and
Limitations for the Significant
Inorganic Chemicals Point Source
Subcategories 397
XI New Source Performance Standards and
Pretreatment Standards 335
Effluent Reduction Attainable by the
Application of the Best Available
Demonstrated Control Technologies,
Processes, Operating Methods or
Other Alternatives 335
Pretreatment Standards for New Sources 337
XII Acknowledgments
341
XIII References 045
XIV Glossary
349
111
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LIST OF ILLUSTRATIONS
Figure No.
1 Aluminum Fluoride Manufacturer at Plant 233 47
2 Aluminum Fluoride Manufacturer at Plant 230 47
3 Ammonium Chloride Production From Soda
Ash Wastes 50
1 Borax Production From Ore 53
5 Boric Acid Manufacture at Plant 269 56
6 Generalized Flow Diagram of Bromine
Manufacture at Plants 216 and 374 59
7 Manufacture of Calcium Carbonate From
Slaked Lime 62
8 Process Diagram for Calcium Carbonate
Production at Plant 382 63
9 Flow Diagram for Calcium Hydroxide
Manufacture at Plant 385 71
10 Hydrogen and Carbon Monoxide Manufacture
at Plant 220 73
11 Generalized Flow Diagram of Chrome
Pigment Complexes 78
12 Chrome Yellow and Molybdate Orange
Manufacture at Complex 332 79
13 Iron Blue, Chrome Yellow and Chrome
Green Manufacture at Complex 332 80
14 Chrome Yellow Manufacture at Plant 326 86
15 Molybdate Orange Manufacture at Plant 326 90
16 Zinc Yellow Manufacturing Flow Diagram
at Plant 326 93
17 Anhydrous Chromic Oxide Pigment Manufacture
at Plant 351 97
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18 Hydrated Chromic Oxide Pigment Manufacture
'at Plant 351 99
19 Chromic Oxide Manufacture at Plant 349 IOC
20 Chromic Acid Manufacture 103
21 Copper Sulfate Manufacture at Plant 302 106
22 Copper Sulfate Manufacture at Plant 299 108
23 Solution Grade Ferric Chloride Production
at Plant 422 111
21 Fluorine Manufacture by Electrolysis
of Liquid Hydrogen Fluoride 114
25 Hydrogen Manufacture by Purification
of Refinery By-Product 116
26 Hydrogen Cyanide Manufacture by the
Andrussow Process 119
27 Simplified Flow Diagram of Hydrogen
Cyanide Manufacture at Plant 321 120
28 Hydrogen Cyanide Process Flow Diagram
for Plant 229 122
29 Iodine Manufacture 126
30 Litharge Manufacturing Process at
Plant 341 131
31 Lead Monoxide Production at Plant 367 133
32 Production of Lithium Carbonate From
Spodumene Ore 136
33 Generalized Process Flow Diagram for
Nickel Sulfate Production at
Plant 213 138
34 Flow Diagram for Manufacture of Oxygen
and Nitrogen at Plant 289 141
35 Generalized Process Diagram for Potassium
Chloride Manufacture From Sylvite Ore 145
36 Potassium Iodide Process Flow Diagram
at Plant 368 148
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37 Silver Nitrate Manufacture 151
38 Sodium Fluoride Manufacture at Plant 343 155
39 Sodium Fluoride Production From Caustic
Soda and Sodium Silicofluoride 156
40 Sodium Silicofluoride Manufacture at
Plant 226 160
41 Sodium Silicofluoride Manufacture at
Plant 247 161
42 Sodium Silicofluoride Manufacture From
an Impure Phosphoric Acid Stream 162
43 Dry Process for Stannic Oxide Production 166
44 Crude Potassium Chloride and Borax
Manufacture at Plant 395 169
45 Refined Potassium Chloride and Bromine
Manufacture at Plant 249 170
46 Boric Acid Manufacture at Plant 314 171
47 Lithium Carbonate Manufacture at
Plant 442 172
48 Zinc Sulfate Manufacture at Plant 478 177
49 Zinc Sulfate Manufacture at Plant 202 179
50 Solubility of Copper, Nickel, Chromium
and Zinc as a Function of pH 208
VI
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LIST OF TABLES
Taole No^ P§ge
1 Significant Inorganic Chemicals 2
2 Effluent Limitations Guidelines and
New Source Performance Standards 4,5
3 1971 U.S. Production of Significant
Inorganic Chemicals 33
4 Raw Waste load From Andrussow Process 123
5 Summary of Cost and Energy Information
for No Discharge of Harmful Pollutants 220
6 Aluminum Fluoride Cost Analysis 224
7 Ammonium Chloride Cost Analysis 225
8 Borax (Ore Mining) Cost Analysis 227
9 Boric Acid (Non-Trona) Cost
Analysis 228
10 Bromine Cost Analysis 230
11 Calcium Carbonate Cost Analysis 231
12 Calcium Hydroxide Cost Analysis 232
13 Carbon Monoxide Cost Analysis 233
14 Chrome Pigments and Iron Blues Cost
Analysis 235
15 Copper Sulfate (Pure Raw Materials) Cost
Analysis 236
16 Copper Sulfate (Recovery Process) Cost
Analysis 237
17 Ferric Chloride Cost Analysis 238
18 Hydrogen Cyanide (Andrussow Process) Cost
Analysis 240
19 Iodine Cost Analysis 242
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20 Lead Monoxide Cost Analysis 2*3
21 Lithium Carbonate Cost Analysis 24^
22 Nickel Sulfate Cost Analysis 245
23 Nitrogen and Oxygen Cost Analysis 247
24 Potassium Chloride Cost Analysis 24£
25 Potassium Iodide Cost Analysis 249
26 Silver Nitrate Cost Analysis 250
27 Sodium Fluoride Cost Analysis 252
28 Sodium Silicofluoride Cost
Analysis 253
29 Zinc Sulfate Cost Analysis 254
30 Estimated June 1973 U.S. Market Price of
Significant Inorganic Chemicals
(Dollars/Ton) 255
31 Conversion Factors 358
vm
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SECTION I
CONCLUSIONS
For the purpose of establishing effluent limitations guide-
lines and standards of performance, the significant
inorganic products segment of the inorganic chemicals
manufacturing point source category was divided into 41
product subcategories consistent with the chemical produced.
This method of categorization reflects differences in the
nature of the raw waste load generated by the manufacture of
different chemicals, as well as the associated treatability
of the waste water. Differences within chemical
subcategories due to plant size, age, geographical location,
product mix, water use, or product purity were generally not
sufficient to necessitate additional subcategorization. In
some cases, product subcategories have been further
segmented to accommodate differences because of dissimilar
manufacturing process employed to produce the same chemical
and because of differences in raw material composition.
This study included 47 of the significant inorganic
chemicals of SIC categories 2813, 2816, and 2819 whose
annual U.S. production volume exceeds 450 metric tons
(1,000,000 pounds) with significant waste discharge
potential. Table 1 lists the significant inorganic
chemicals studied in this report.
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TABLE 1
SIGNIFICANT INORGANIC CHEMICALS
1. aluminum fluoride
2. ammonium chloride
3. ammonium hydroxide**
4. barium carbonate**
5. borax
6. boric acid
7. bromine
8. calcium carbonate
9. calcium hydroxide
10. carbon dioxide**
11. carbon monoxide
12. chrome green*
13. chrome yellow and
orange*
14. chromic acid
15. chromic oxide*
16. copper sulfate
17. cuprous oxide**
18. ferric chloride
19. ferrous sulfate**
20. fluorine
21. hydrogen
22. hydrogen cyanide
23. iodine
24. iron blues*
25. lead oxide
26. lithium carbonate
27. manganese sulfate**
28. molybdate chrome orange*
29. nickel sulfate
30. nitric acid (strong)**
31. nitrogen
32. oxygen
33. potassium chloride
34. potassium iodide
35. potassium permanganate**
36. silver nitrate
37. sodium bisulfite**
38. sodium fluoride
39. sodium hydrosulfide**
40. sodium hydrosulfite**
41. sodium silicofluoride
42. sodium thiosulfate**
43. stannic oxide
44. sulfur dioxide**
45. zinc oxide**
46. zinc sulfate
47. zinc yellow*
*Combined as chrome pigments and iron blues in one
production subcategory.
**Publication of regulations for these significant
inorganic chemicals is being deferred due to further
consideration and data analysis.
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SECTION II
RECOMMENDATIONS
The effluent limitations guidelines representing tne
effluent reduction attainable by the application of best
practicable control technology currently available and the
effluent reduction attainable by the application of best
available technology economically achievable are shown in
Table 2. Also snown are the new source performance
standards for each chemical subcategory,
Tne figures shown in the table represent the limitation of
an average of daily values for 30 consecutive days. In most
cases, the maximum for any one day is twice the 30 day
average. However, the maximum for any one day limit based
on BPCTCA is three times the thirty day average for the
following batch processes: chrome pigments, copper sulfate,
lithium carbonate (spoduuieme ore) , nickel sulfate, potassium
iodide and silver nitrate. All process water must be within
the pH range of 6.0 to 9.0. Limitations apply to discharge
of process waste water pollutants to navigable waters.
Effluent limitations for rioncontact cooling water and waste
streams resulting from steam and water supply are being
developed in a separate study.
Fourteen of the
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V
I
T
Z
AA
AB
AC
AD
AE
AF
AG
AH
AI
AJ
AK
AL
AM
AN
AO
AP
Product Subci .eirory
tiimlnm Fluoride
Anmonium Chloride
(a) Anhydrous
(b) Solvay By-product
Anmonium Hydroxide
Barium Carbonate
Borax
Boric Acid
(a) Trona
(b) Ore-Mined Bcrax
Bromine
Calcium Carbonate
(a) Milk of Ure
(b) Solvay Recovery
Calcium Hydroxide
Carbon Dioxide
Carbon Monoxide and
By— product Hydrt>*^n
(Refonnlng Process)
Chrome Plgpmits and
Iron Blues
Chronic Acid
""topper Sulfate
(a) Pure Raw Katerli 1
(b) Recovery Process
Cuprous Oxide
Ferric Chloride
Ferrous Sulfate
Fluorine
(a) Liquid HP Electrolysis
Process
Hydrogen (Refinery By-product)
Hydrogen Cyanide
(a) Acryloritrlle by-prodsct
(b) Andrusscw Process
TAKE 2. EFT.;":
AtC HEM SO.T5.T
5FCTCA C.-^VJc,-
Fluoride
TSS
no discharge of
faxf\la (as N)
Reserved
Reserved
no discharge cf
TJO dlscr^ree o"
Arsenic
TSS
no discharge of
TSS
no discharge of
Reserved
CO)
TSS
Chrorij-. (7)
Chroniizs (6+)
Lead
Zinc A (t)
Cyanide A (5}
Cyanide (51
Iron (y)
no discharge of
Copper
TSS
Copper
ttlckel
Seleniun
Reserved
no discharge of
Reserved
no discharge o!
no discharge ol
r.o -JlGcharge o.
TVS
Cyanide
Cyartl '\f A
A.T*jnla (as 1!)
;^.«
«
0.31
0.13
C.17
**%*
Cfcnp
rwwr
0.0011
C.07
pwwp
0.28
pw«p
0.25
0.06
1.7
O.IH"
0.27
C.C031
0.031
0.27
pwwp
0.0002
0.023
0.001
0.002
0.0005
pwwp
• pwwp
• pwv.p
P 1.2
0.025
O.C025
oiis
N ourrnj?ES
STKCARES
Lliv.'. '.a' Icrii b.iscd or.
E-A'.TVi (Iv/kkr,)
Fluoride 0.031
TSS O.C2£
Alurinum 0.017
no discfianie of pwwp
no discharge of pwwp
Reserved
Reserved
no discharge of pwwp
no discharge of pwwr-
Arsenic 0.0011
TSS O.C28
no discharge of pwwp
TSS 0.11
TSS 0.23
no discharge of pwwp
Reserved
COD 0.065
TSS 0.017
TSS 0.33
Chromiun (T) 0.017
Chronium (6+) O.C017
Lead 0.033
Zinc A (1) 0.067
Cyanide A (5) 0.0017
Cyaiidf '"•) 0.017
Iron (5) 0.067
no discharge of pwwp
Copper 0.0002
TSS 0.0016
Copper 0.00016
Nickel 0.00016
Selenium 0.00023
Reserved
no discharge of pn*p
Reserved
no discharge of pv»p
no discharge of pmf
no discharge of pwtp
TGG 0.015
Cyanide 0.0023
Cy.inMf A 8.'.0i~23
RODr 0.006
Anrrionla (a i If) O.^lG
'Jew Source Ft«:
Standard (it.
Fluoride
TSS
no discharge
nc dlscharce
Reserved
Reserved
no discharge
nc -_scr^r^e
Arsenic
TSS
no discharge
TSS
TSS
no discharge
Feserved
• ccc
TSS
TSS
Chroraiici (?)
Chrcciur. '£+)
Lead
Zinc A '"0
Cyanide A (5
Cyanide C;
Ircn (^
no discharge
Copper
TSS
Copper
Nickel
Seleni'jn
Reser"/ed
no discharge
Reserved
no dlscrarge
no discharge
no rtl.icnaoy;
Arrr/>r. ' a f a.i
•tctnarce
0.03A
0.026
0.017
;f pxxp
if pwwp
of p«"«p
:f rw«:
cf pwwp
c.n
0.23
if pwwp
u.065
C.C17
C.33
O.C17
3.:017
0.033
0.067
:.ooi7
:.ci7
of p«,p
C.0002
0.0016
0. 00016
0.00016
C. 00023
Cf ;wp
of pwwp
of pwwp
of r-<-vP
0.015
0.0023
0.00023
0.056
11) 0.016
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AQ
A?
AS
AT
A:'
AV
AW
AX
AY
AZ
BA
BB
BC
BD
BE
BF
B3
BH
El
EJ
EK
•fXES:
Iodine
Lead .'tacxl-i-
Llthl'.ri Carbonate
(a) 7rona Process
(b) Spccjnrne C:-e
Xsnganese Suifate
Nickel Sulfate
(a) Pure Taw y^rerials
(t) L-pure Saw laterials
Nitric Acid ^Strong)
Crj'ger. and Nitrogen
Potasslun 2ilcride
Potassijn-. Iodide
Potassium Pemar^anate
Silver Nitrate
Sodluc Bisulfite
Sodlm Fluoride
SodiiiB Rydrosulflde
Sodlm Hydrosulfite
Sodi-j3 Sillccfl-oride
Sodiim ThlosuifEte
Starrlc Oxide
(a) Dry Process
Solfur Dioxide
Zir£ Cadde
Zinc Suifate
(1; F"""P is trie sccr^viatlon for
'*',-': -~~ fY,- .= "" '' '~^~'fjc^> aril L*
no discharge of
no discharge of
no discharge of
TSS
Reserved
no discharge of
Nickel
TSS
Reserved
Oil and Grease
no discharge of
TSS
Sulfide
Iron
Barliin
Reserved
Silver
TSS
-Reserved
no discharge of
Reserved
Reserved
Fluoride
TSS
Reserved
no discharge of
Reserved
Reserved
no discharge of
process waste xab
-»^_^-^^'- • — .j.-i-«»-
*arj3ar^;-j ^ o *..-...*.
pwwp
pwwp
0.9
pwwp
0.002
0.032
0.001
pwwp
0.03
0.005
0.005
0.003
0.003
0.023
Pwwp
0.25
0.3
PW-P
pwwp
er pollutarts.
no disc^iarr.e of
no discharge of
no discharge of
TSS
Reserved
no discharge of
Nickel
TSS
Reserved
Oil ard Grease
no discharge of
TSS
Sulfide
Iron
Bar Inn
Reserved
Silver
TSS
Reserved
no discharge cf
Reserved
Reserved
Fluoride
TSS
Reserved
no discharge of
Reserved
Reserved
no discharge of
tc 9.0.
pwwp
pwwp
pwwp
0.36
pwwp
0.002
0.012
0.001
pwwp
0.011
0.0036
0.0036
0.0023
0.0015
0.023
pwwp
0.25
0.19
PWWP
no discharge of
no discharge of
no discharge of
TSS
Reserved
no discharge of
Nickel
TSS
Reserved
Oil and Grease
no discharge of
TSS
Sulfide
Iron
Barium
Reserved
Silver
TSS
Reserved
no discharge of
Reserved
Reserved
Fluoride
TSS
Reserved
no discharge of
Reserved
Reserved
no dlscnarge of
pwwp
pwwp
pwwp
0.36
pwwp
o.oo:
0.012
0.001
pwwp
0.014
O.OC3
0.003
O.D02
0.001
0.023
Pwwp
0.25
0.19
pwwp
pv.-p
Effljer.t ll-Itailar--. and standards listed are for the ave-rar? of
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SECTION III
INTRODUCTION
PURPOSE AND AUTHORITY
The United States Environmental Protection Agency (EPA) is
cnarged under the Federal Water Pollution Control Act
Amendments of 1972 with establishing effluent limitations
which must be achieved by point sources of discharge into
the navigable water of the United States.
Section 301(b) of the Act requires the achievement by not
later than July 1, 1977, of effluent limitations for point
sources, other than publicly owned treatment works, which
are based on the application of the best practicable control
technology currently available as defined by the
Administrator pursuant to Section 304(b) of the Act.
Section 301(b) also requires the achievement by not later
than July 1, 1983, of effluent limitations for point
sources, other than publicly owned treatment works, which
are based on the application of the best available
technology economically achievable which will result in
reasonable further progress toward the national goal of
eliminating the discharge of all pollutants, as determined
in accordance with regulations issued by the Administrator
pursuant to Section 30U(b) to the Act. Section 306 of the
Act requires the achievement by new sources of a Federal
standard of performance providing for the control of the
discharge of pollutants which reflects 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. Section 304 (b) of the Act requires the
Administrator to publish within one year of enactment of the
Act, regulations providing guidelines for effluent
imitations setting forth the degree of effluent reduction
attainable through the application of the best practicable
control technology currently available and the degree of
Affluent reduction attainable through the application of th-
-est control measures and practices achievable including
reatment techniques, process and procedure innovations,
operation methods and other alternatives. The regulations
proposed herein set forth effluent limitations guidelines
pursuant to Section 304 (b) of the Act for the inorganic
chemicals manufacturing point source category.
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Section 306 of the Act requires the Administrator, within
one year after a category of sources is included in a list
published pursuant to Section 306 (b) (1) (A) of the Act to
propose regulations establishing Federal standards of
performances for new sources within such categories. The
Administrator published in the Federal Register of January
16, 1973 (38 F.R. 162U), a list of 27 source categories.
Publication of the list constituted announcement of th*
Adnunxstrator's intention of establishing, under Section
3Qh, standards of performance applicable to new sources
within the inorganic chemical manufacturing point source
category, which was included within the list published
Oaiiuary 16, 1973.
SUMMARY OF METHODS USED FOR DEVELOPMENT OF EFFLUENT
LIMITATIONS GUIDELINES AND STANDARDS OF PERFORMANCE
The Environmental Protection Agency has determined that a
rigorous approach including plant surveying and verification
testing is necessary for the promulgation of effluent stand-
ards from industrial sources. A systematic approach to the
achievement of the required guidelines and standards
includes the following:
a) categorization of the industry and determination of those
industrial categories for which separate effluent limita-
tions and standards need to be set;
b) characterization of the waste loads resulting from dis-
charges within industrial categories and subcategories;
c) identification of the control and treatment technology
within each industrial category and subcategory;
dj identification of those plants having the best practical
technology currently available {exemplary plants); and
e) generation of supporting verification data for the best
practical technology including actual sampling of plant
effluents by field teams.
The culmination of these activities is the development of
the guidelines and standards based on the best practicaDle
current technology.
This report describes the results obtained from application
of the above approach to the inorganic chemicals industry.
Thus, the survey and testing covered a wide range of pro-
cesses, products, and types of wastes. Studies of a total
of 47 chemicals, listed in terms of products below, are
-------
summarized in this report. Twenty-five other major inor-
ganic products were covered in the first phase of this
study.
Selected Inorganic Chemicals with Production
Greater Than <&54 Metric Tons Per Year
(500 Tons Per Year)
aluminum fluoride
ammonium chloride
ammonium hydroxide*
barium carbonate*
borax
boric acid
bromine
calcium carbonate
calcium hydroxide
carbon dioxide*
carbon monoxide
chrome green
chrome yellow and orange
chromic acid
chromic oxide
copper sulfate
cuprous oxide*
ferric chloride
ferrous sulfate*
fluorine
hydrogen
hydrogen cyanide
iodine
*Reserved.
iron blues
lead oxide
lithium carbonate
manganese sulfate*
molybdate chrome orange
nickel sulfate
nitric acid (strong)*
nitrogen
oxygen
potassium chloride
potassium iodide
potassium permanganate*
silver nitrate
sodium bisulfite*
sodium fluoride
sodium hydrosulfide*
sodium hydrosulfite*
sodium silicofluoride
sodium thiosulfate*
stannic oxide
sulfur dioxide*
zinc oxide*
zinc sulfate
zinc yellow
The effluent limitations guidelines and standards of
performance proposed herein were developed in the following
manner. The point source category was first categorized for
the purpose of determining whether separate limitations and
standards are appropriate for different segments within a
point source category. Such subcategorization was based
upon raw material used, product produced, manufacturing
process employed, and other factors. The raw wastes charac-
teristics for each subcategory were then identified. This
included an analysis of (1) the source and volume of water
used in the process employed and the sources of waste and
waste waters in the plant; and (2) the significant
constituents of all waste waters which result in degradation
of the receiving water. The constituents of waste waters
-------
which should be subject to effluent limitations guidelines
and standards of performance were identified.
The full range of control and treatment tecnnologies
existing within each subcategory was identified. This
included an identification of each control and treatment
technology,, including both in-plant and end-of-process
technologies, which are existent or capable of being
designed for each subcategory. It also included an
identification of the amount of constituents (including
thermal) and the characteristics of pollutants resulting
from the application of each of the treatment and control
technologies. The problems, limitations and reliability of
each treatment and control technology were also identified.
In addition, the non-water quality environmental impact,
such as the effects of the application of such technologies
upon other pollution problems, including airr solid waste,
noise and radiation were also identified. The energy
requirements of each of the control and treatment
technologies were identified as well as the cost of the
application of such technologies.
Cost information contained in this report was obtained
directly from industry during exemplary plant visits, from
engineering firms and equipment suppliers, and from the
literature.
The information obtained from the latter three sources has
been used to develop general capital, operating and overall
costs for each treatment and control method. Costs have
been put on a consistent industrial calculation basis of ten
year straight line depreciation plus allowance for interest
at six percent per year (pollution abatement tax free money)
and inclusion of allowance for insurance and taxes for an
overall fixed cost amortization of fifteen percent per year,
This generalized cost data plus the specific information
obtained from plant visits was then used for cost
effectiveness estimates in Section VIII and wherever else
costs are mentioned in this report.
The data for identification and analyses were derived from a
number of sources. These sources included EPA research
information, published literature, qualified technical
consultation, on-site visits and interviews at numerous
inorganic chemical plants throughout the U.S., interviews
and meetings with various trade associations, and interviews
and meetings with various regional offices of the EPA. All
references used in developing the guidelines for effluent
10
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limitations and standards of performance for new sources
reported herein are included in Section XIII of this report.
Exemplary Plant Selection
The following exemplary plant selection criteria were
developed and used for the selection of exemplary plants.
a) Discharge effluent quantities
Plants with low effluent quantities or no discharge of
process waste water pollutants were preferred. This minimal
discharge may be due to reuse of water, raw material
recovery and recycling, or to use of either pond or forced
evaporation. The significant parameter was minimal waste
added to effluent streams per weight of product
manufacturered.
b) Water management practices
Use of good management practices such as water reuse, plan-
ning and in-plant water segregation, and the proximity of
cooling towers to operating units where airborne
contamination of water can occur were considered.
c) Air pollution and solid waste control
Exemplary plants must possess overall effective air and
solid waste pollution control where relevant in addition to
water pollution control technology. Care was taken to
insure that all plants chosen have minimal discharges into
the environment or have a waste treatment system.
d) Effluent treatment methods and their effectiveness
Plants selected generally have in use the best currently
available treatment methods, operating controls, and
operational reliability. Treatment methods considered
included basic process modifications which significantly
reduce effluent loads as well as conventional end-of-pipe
treatment methods.
e) Plant management philosophy
Plants were preferred whose management insists upon
effective equipment maintenance and good housekeeping
practices. These qualities are best identified by operation
at. a high percentage of capacity and plant cleanliness.
f) Raw materials
11
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Differences in raw material purities were given strong con-
sideration in cases where the amounts of wastes are strongly
influenced by the purity of raw materials used. Several
plants using different grades of raw materials were
considered for those chemicals for which raw material purity
is a determining factor in waste control.
g) Diversity of processes
On the basis that all of the above criteria are met, consid-
eration was given to installations having a multiplicity of
manufacturing processes. However, for sampling purposes,
the complex facilities chosen were those lor which the
wastes could be clearly traced through the various process
and waste treatment steps.
Sampling of Exemplary Plants
The details of how the exemplary plants were sampled and the
analytical techniques employed are fully discussed in
Supplement B of this report.
GENERAL DESCRIPTION OF .INDUSTRY BY PRODUCT
A brief description of production methods,, production
volumes, and product uses of the various inorganic chemicals
studied is presented below. The description is organized so
that each product chemical is discussed separately and in
alphabetical order.
The information on the various manufacturing processes
described herein was collected from industry personnel.
Some additional detail concerning production processes,
operating conditions, raw materials, etc., may be obtained
for many of the chemicals from References 1, 2, and 3. The
uses reported were determined from industry personnel, the
Merck Index(4), and various other sources. Specific
references to statements in the description are denoted by
superscripts.
Most of the production or sales figures stated were derived
from the Bureau of Census (U.S. Department of Commerce)
publications. These figures for all of the chemicals are
tabulated for convenience in Section 3.2, immediately after
the industry description of the 47 products.
Aluminum Fluoride
12
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Aluminum fluoride is produced by the reaction of hydrated
alumina with hydrogen fluoride. The overall equation for
the reaction is:
A1203.3H20 + 6HF = 2A1F3 * 6H2O.
The hydrated alumina and anhydrous (gaseous) hydrogen
fluoride are added to a reactor. The solid product is
cooled and readied for shipment. In some plants the
reaction takes place in aqueous solution, from which the
water must be driven off to effect recovery of the solid
product.
Production by other processes such as ammonium alum and
phosphate rock processing are not included in this study.
Aluminum fluoride is used as a raw material in the
production of cryolite (sodium f luoraluminate) , which in
turn is used in the production of aluminum. It is also used
as a metallurgical flux, in ceramics, as an inhibitor of
fermentation, and as a catalyst in organic reactions. Total
sales of aluminum fluoride in the United States during 1971
were 143,000 kkg (158,000 tons), but much more was produced
captively for use by aluminum manufacturers.
Ammonium Chloride
Ammonium chloride (sal-ammoniac) is produced by three
methods. Most of the production arises as a by-product in
the manufacture of sodium carbonate (soda ash) by the Solvay
(ammonia-soda) process. A second process produces ammonium
chloride by the reaction of gaseous hydrogen chloride with
liquid anhydrous ammonia. A third process uses aqueous
hydrogen chloride and anhydrous ammonia and is not covered
in this study.
The anhydrous hydrogen chloride, anhydrous ammonia process
is represented by:
H2. + C12 = 2HC1
HC1 + NH3 anhydrous = NH4C1.
:
-------
In the Solvay process used to manufacture soda ash, the
final brine (distiller waste liquor) may be evaporated to
recover sodium chloride. This leaves a 50 percent" by weight
solution of calcium chloride. This solution, together with
ammonia and carbon dioxide, is charged to an autoclave in
which the following reaction takes place:
CaC12 + 2NH3 + C02 + H2O = 2NHUC1 * CaCO3.
From this the precipitated carbonate is filtered, and the
sal-ammoniac is recovered by crystallization.
Alternatively, some of the filtrate feed to the ammonia
recovery still in the Solvay process may be diverted,
evaporated to recover sodium chloride, and then cooled to
crystallize ammonium chloride. This product is then puri-
fied by recrystallization.
A typical commercial product contains 0.5 percent sodium
chloride. Uses include pharmaceutical preparations, the
manufacture of dry cell batteries, dyeing, freezing
mixtures, electroplating, explosives, use as washing
powders, as a soldering flux, as a chemical reagent, and as
a medicinal additive to livestock feed. The estimated
production rate in the U.S. is 20,000 to 25,000 kkg/year
(about 25,000 tons/year).
Borax
The major source of borax in the world is the deposits near
Searles Lake and other nearby areas of southern California.
One production process utilizes sodium borate ores
containing 20 to 30 percent boric oxide in the form of
hydrated sodium tetraborate (borax) and the remainder
insolubles. The ore is crushed and conveyed to dissolvers
where water and recycled mother liquor are added to dissolve
the borax. The insolubles are settled out in ponds, and the
clarified borax solution (mother liquor) is fed to
crystallizers where a slurry of borax crystals in water is
formed. The borax is separated from the water by
centrifugation, dried, screened and packaged. The product
borax is a hydrated sodium tetraborate, Na2BfK>7.10H2O. For
boric acid manufacture the pentahydrate, Na.2jBjK)7.5H20, is
produced.
Borax is also made from Searles Lake (Trona) brines con-
taining borax concentrations as low as two percent in solu-
tion. The brine is concentrated by evaporation, and potas-
sium chloride is selectively crystallized out, leaving a
saturated solution of borax. Borax is then crystallized
14
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out, filtered, redissolved and crystallized again for
purification, centrifuged and dried.
Borax is used in the production of boric acid and borate
chemicals, as a laundry product, in the glass and ceramics
industries, as a flux, and in the manufacture of soaps and
agricultural chemicals. Total U.S. sales in 1971 were
525,400 kkg (579,000 tons).
Boric Acid
Most of the U.S. boric acid production results from acidifi-
cation of a saturated solution of borax:
Na2B4O7«5H2O + H2SO4 * 1OH2O = 4H3BO3 + Na2SO4 o 10H2O.
From the acidulator, the boric acid solution is fed to a
vacuum crystallizer,? where boric acid crystals are formed,
and then to a filter. The sodium sulfate is removed in the
filtratej, and the technical grade boric acid is dried and
packaged* The technical grade product can also be diverted
upstream of the final drying step, redissolved,
crystallized^ filtered, and dried to produce a higher purity
product* The yield from this process is about 90 percent
theoretical.
Boric acid is also obtained from Searles Lake well brines
and from weak end liquors from the process described above.
This process involves extraction of the boric acid and
borates with kerosene containing an appropriate chelating
agent. The organic phase is fed to a mixer-stripper and
contacted with dilute sulfuric acid, which forms boric acid
from borates by the reaction given above and also strips the
boric acid present from the organic phase. The two phases
are gravity-separated, and the kerosene is recycled., The
aqueous phase is treated with activated carbon to remove any
organics remaining and then is evaporated and the boric acid
crystallized. The boric acid crystals are centrifuged,
Iried, and packaged for sale.
Boric acid is a weak acid which is used medicinally as a
mild antiseptic. It also finds use in chromic oxide
manufacture, in the manufacture of glazes and enamels for
pottery and similar products, in weather proofing, textile
c?ber glass, heat resistant glass, and in atomic power
slants as a nuclear moderator. The total U.S. production
In 1971 was 95,400 kkg (105,000 tons).
Bromine
15
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Sromine is extracted from sea water, which typically
contains bromide ions at 65-70 mg/1 concentration. Fr<=>e
chlorine gas is added to the sea water to oxidize the
bromide to free bromine. The bromine is removed in an air
stream which is then treated with sulfurous acid to remove
bromine as hydrobromic acid. The acid solution is treated
with chlorine gas which reoxidizes the bromide back to free
bromine. The overall reaction scheme is as follows:
2NaBr + C12 = Br2 «• 2NaCl
Br2 + S02 + 2H20 = 2HBr + H2SO4
2HBr + C12 = Br2 + 2HC1.
After the second chlorine oxidation, the vapors (bromines
and water) are condensed, and the crude bromine is removed
from the bottom of a decanter. The product is stored,
packaged or transported to plant units which utilize it.
The overall efficiency of the recovery is 90 to 95 percent.
Bromine is also produced from well brines which contain bro-
mide in far greater concentrations than sea water. In this
process only one oxidation by chlorine is required. Crude
bromine is condensed, separated from the water present by
distillation, and dried.
Most of the U.S. bromine production is used to manufacture
ethylene dibromide, a constituent of "anti-knock" additives
to gasoline. It is also used in the manufacture of methyl
bromide, inorganic bromides, organic dyes, and flame-
retardant materials. The total amount of bromine shipped in
the U.S. during 1971 was 38,000 kkg (42,000 tons). This
excludes the bromine production used in-plant to produce
ethylene dibromide, which would appear to be most of the
total production.
Calcium Carbonate
Calcium carbonate is produced in the United States by three
processes. One process involves the hydration of lime to a
milk-of-lime solution and precipitation of the carbonate
through treatment with carbon dioxide. The precipitated
carbonate is filtered, dried, milled, and packaged for sale.
The overall reaction scheme starting with calcium oxide is:
CaO + H2O = Ca (OH) 2
Ca(OH)2 + C02 = CaC03 + H2O.
16
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The other two production processes involve the reaction of
sodium carbonate (soda ash) and sodium bicarbonate with
calcium chloride in solution to form the relatively
insoluble calcium carbonate. These reactions are:
Na2CO3 + CaCl2 = CaCO3 + 2NaCl
NaHC03 + CaC12 + NaOH = CaCO3 + 2NaCl + H2O.
In one of these processes, calcium chloride by-product from
soda ash manufacture is mixed with a soda ash-bicarbonate
mixture (derived from partial decomposition of crude sodium
bicarbonate, bicarbonate in spent liquors, and additional
soda ash solution from the soda ash plant) and caustic soda
in a we11-stirred reaction tank. The resulting calcium
carbonate slurry is thickened, filtered, washed, and dried
in a spray dryer. The dried particles are collected and
packaged. Ultra-fine calcium carbonate is produced in a
similar manner except that higher purity raw materials are
used and the final drying process utilizes a tunnel drier.
The third production process for calcium carbonate arises
from pretreatment of calcium chloride-containing brines to
remove calcium prior to use of the brines in chlor-alkali
production. Sodium carbonate addition to heated brine
causes precipitation of the calcium carbonate by the soda
ash-calcium chloride reaction shown above. The solids are
typically filtered out and treated as in one of the previous
processes.
Calcium carbonate is a very widely used chemical both in a
pure and an impure state. The impure state includes marble
chips and dust, pulverized and levigated limestone, and
whiting produced from natural chalk. The pure form,
produced by the three processes described above, finds its
major uses in the paint, rubber, pharmaceutical, cement, and
paper industries. Total D.S. production of pure calcium
carbonate in 1971 was 165,000 kkg (182,000 tons).
Calcium Hydroxide
The production process for calcium hydroxide (slaked lime)
involves simply the addition of water to chemical lime
(calcium oxide, or quicklime):
CaO * H2O = Ca(OH).2.
In the typical industrial process, fresh lime from the lime-
stone calcining kiln is cooled, milled, and introduced with
water into a water-cooled hydrator. When steam evolution
17
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has ceased, the product is sized and stored for aging or
packaged. of the lime sold on the open market, about 20
percent is hydrated or slaked lime, the remainder being
quicklime. Hydrated lime is used to a great extent in the
construction industry (mortar and other cements, plaster,
stucco, etc.). It is also used as a mild alkali in
industry, for removing hair from hides, for water softening,
in insecticides and other agricultural products, and in
kerosene purification. A solution of calcium hydroxide in
water is called limewater, and this is sometimes used
medicinally. The amount of calcium hydroxide sold as
calcium hydroxide in the United States during 1970 was
39,000 kkg (U2,000 tons). It is estimated that several
million metric tons per year are sold as slaked lime.
Another process is used for preparation of high purity
specialty grades of calcium hydroxide by use of calcium
chloride and sodium hydroxide as follows:
CaCl2 + NaOH = Ca (OH) 2 + NaCl.
This process is excluded from this study.
Carbon Monoxide
Carbon monoxide is produced as a by-product of hydrogen pro-
duction from methane (natural gas). The reaction is:
2CH4 + 02 = l»H2 + 2CO.
The resulting gas mixture is freed of carbon dioxide and
other impurities in ethanolamine scrubbers, and separated
into the two major components by liquefaction of the carbon
monoxide.
Carbon monoxide is an important raw material for the syn-
thesis of alcohols, diisocyanate, ethyl acrylate, and other
industrial organic compounds. It is very poisonous when
inhaled and must be handled carefully. Estimated U.S. sales
are about 135,000 kkg (150,000 tons) per year.
Chrome Green
This pigment, sold under various names, is a mixture or co-
precipitate of chrome yellow and Prussian (iron) blue pig-
ments. See the subsections on these two pigments for their
production processes. To make chrome green the two are
physically mixed prior to grinding or coprecipitated from
solution and then dried, ground, and packaged. Chrome green
18
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is used as a paint pigment, and 2,450 kkg (2,700 tons) was
produced in the U.S. during 1971.
Chrome Yellow and Orange
Chrome yellow pigments are the most widely used yellow pig-
ments in this country. They include a wide variety of
shades ranging to orange, which is also termed chrome
orange. Chrome yellow pigment is basically a mixture of
lead chromate, lead sulfate, and zinc sulfate, whereas
chrome orange pigment contains basic lead chromate and lead
sulfate. Various mixtures and proportions are used to
produce the range of shades.
The primary ingredient of chrome yellow pigment is lead
chromate, which is produced by the reaction of sodium
chromate or dichromate with lead nitrate or acetate. A
typical reaction used is:
Na2CrO4 + Pb(NO3_)2 = 2NaNO3 * PbCrO4.
The lead nitrate is often obtained in-plant by reacting lead
oxide (litharge) or pig lead with nitric acid. If zinc sul-
fate is to be in the pigment mixture, it is prepared by:
ZnO + H2SO4 = ZnSOj* + H2O,
If lead sulfate is to be in the pigment mixture, it is
formed by the addition of sodium sulfate to the reaction
vessel in which lead chromate is formed. The reaction with
the lead nitrate is:
Na2SO
-------
Chrorrlc Acid (Chromium Trioxide and Chromic Anhvdriell
Chromic acid, the conunercial name for chromium trioxide, is
produced by the acidification of sodium dichromate with sul-
fur ic acid:
Na2Cr207 + H2SO4 = 2Cr03 + Na23O£ + H2O.
Following this reaction, the sodium sulfate is removei by
filtration, evaporation, and crystallization. The saturated
chromic acid solution is then fed into another crystallizer ,
from which a slurry containing crystals of chromic acid is
discharged to a centrifuge for separation, while the mother
liquor is recycled. The chromic acid is dried and packaged
as technical grade or purified.
The process may also be carried out without the presence of
water, in which case the reactants are sodium dichromate and
fuming sulfuric acid. The reaction may be represented by:
Na2Cr207 + 2H2S04 = 2NaHSO4 + 2CrO3 + H2O.
The products are molten, and the heavier chromic acid is
removed, cooled, flaked and packaged or purified by r»-
crystallization.
Chromic acid is used as an oxidizing agent in organic syn-
thesis, but the major uses are for .netal treatment (chrome
plating, copper stripping, aluminum anodizing, and other
corrosion protection processes) . Most chromic acid is made
in plants that also produce sodium dichromate from which it
is made. Chromic acid produced in plants that do not also
make sodium dichromate is not covered in this study. Total
U.S. production of chromic acid in 1971 was 19,*400 kkq
(21,300 tons) . y
Chromic Oxide
The currently favored method of preparing chromic oxide is
by the calcination of sodium dichromate with sulfur or
carbon in a reverbatory furnace:
+ S = Cr2O3 + Na2SO4
Na2Cr207 + C = Cr2O3 * Na2CO3 + COI.
Sodium sulfate from the first reaction above or soda a~h
from the second is removed by washing, and the chromic oxide
is filtered, dried and packaged. Chromic oxide for pi.).nor,L-i
is made with sulfur; that for aluminothermic chromiu. is
20
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made with charcoal or some other low-sulfur carbonaceous
material.
Guignet's green (hydrated chromic oxide) is not a true
hydrate but a hydrous chromic oxide of approximate formula,
Cr2O3_.2H2O. It results from the tiring of a mixture of
potassium dichromate and boric acid at about 550°C. The
product is leached, filtered, washed, and dried. The
pigment product is about 81 percent chromic oxide, 17
percent water, and about 2 percent boric acid (formerly
considered necessary but now regarded as an impurity).
Chromic oxide is the most stable green pigment known, and is
used where chemical or heat resistance is important. Uses
include coloring of cement and ceramics (including granules
used in roofing materials) and paints (including camouflage
paints because of its reflectance spectrum). Anhydrous
chromic oxide is also valuable in the manufacture of
chromium metal and aluminum-chromium master alloys.
Guignet's green (hydrous chromic oxide) is a widely-used
pigment, particularly in automotive finishes. Total U.S.
sales of chromic oxide in 1971 were 6,000 kkg (6,600 tons).
Copper Sulfate
Copper sulfate, also called blue vitriol, is produced by the
reaction of sulfuric acid with copper shot (blister copper
from smelter) and air:
2Cu + 2H2SOU. + O2 = 2CuSO4 + 2H2O.
Either concentrated or dilute acid may be used. In general,
the resulting solution is evaporated and subjected to a
series of crystallization steps to obtain copper sulfate
crystals, which are then centrifuged, air-dried, screened,
and packaged for sale. Some manufacturers begin with copper
oxide instead of the metal, but the process is similar.
Other processes were not included in this study.
Copper sulfate, the most important compound of copper, has a
number of uses. It is a biocide, and uses associated with
this property include use as a mixture with milk of lime to
form Bordeaux mixture and addition to water reservoirs as an
algicide. It is widely employed in electroplating
operations, in wood preservation (with sodium chromate), and
for addition to copper-deficient soils. The total U.S.
production in 1971 was 30,500 kkg (33,700 tons).
F_erric Chloride
21
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Ferric chloride is made from steel pickling liquors
(containing ferrous chloride and hydrochloric acid) to whicn
are added iron, chlorine, additional hydrochloric acid, and
water. The ferric chloride solution so formed is sold at 40
percent ferric chloride, with or without filtration to
remove suspended solids. The overall reactions involved may
be represented by:
Fe + 2HC1 = FeC12 + H2
2FeC12 * C12 = 2FeC13.
Ferric chloride produced by other processes is not
in this study.
included
Uses of ferric chloride include photoengraving and photo-
graphy, manufacture of other iron salts, pigments, dyes, and
inks, as a reaction catalyst, in purification and de-
odorization of factory effluents and sewage, arid in chlo-
rination of silver and copper ores. Total U.S. sales in
1971 were 68,000 kkg (75,000 tons).
Fluoride
Elemental fluorine is produced by several types of anhydrous
electrolytic processes differing primarily in the
composition of the electrolyte used and the cell operating
temperature. The fluorine-containing species is either
anhydrous liquid hydrogen fluoride, or potassium acid
fluoride, and the respective reactions for these are:
elec
2HF = F2
H2
elec
2KHF2 = 2KF
F2 + H2.
In the former process the only species involved are hydrogen
and fluorine. The condensation of the fluorine yields a
pure product. In the latter process the potassium fluoride
is recycled through:
KF + HF = KHF2.
The gaseous products from the potassium acid fluoride elec-
trolysis are also separated by condensation of the fluoride.
Fluoride gas is costly and has relatively limited usage.
The two major uses are the production of uranium
hexafluoride used in uranium isotope separation and the
22
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production of sulfur hexafluoride used to insulate high
voltage components. Some is also used in fluorination of
organic compounds, but most fluorocarbon production utilizes
hydrogen fluoride instead of fluorine. Production figures
are not made available because of national security
implications.
Hydrogen
Hydrogen is derived commercially from hydrocarbons and/or
water. Commercial quantities are obtained as by-products
from petroleum refining operations, synthetic chemical manu-
facture, chlor-alkali manufacture, and coke oven gas, but
the major commercial production is by catalytic reforming of
hydrocarbons (typically methane) with steam. The reforming
processes are portions of the petroleum industry and were
thus not covered in this study, but a considerable amount of
the crude hydrogen from reforming is sold and is purified
elsewhere. This purification process, consisting of oxygen
removal, drying, and cooling in liquid nitrogen heat
exchanger plus further refrigeration to remove the last
traces of impurities, was made a subject of this program.
The other production process covered under this program is
partial oxidation of hydrocarbons. The hydrocarbon, ranging
from natural gas (mostly methane) to fuel oil, and oxygen or
air (plus steam if required) are preheated and introduced
i-ito a reforming reactor where the partial oxidation takes
place. The oxidation reaction for methane may be
represented by:
2CHU + 02 = 2CO + 4H2.
If carbon monoxide is to be the coproduct, the product gases
are treated to remove carbon and carbon dioxide, separated,
compressed and sold. If carbon dioxide is to be the
coproduct, steam is included in the reactor feed; and the
product gases from the reactor are introduced to a shift
converter in which the carbon monoxide reacts with the steam
to form carbon dioxide and additional hydrogen:
CO + H20 = H2 + C02.
These product gases are then separated, purified, and
prepared for sale.
The largest use of hydrogen is in the manufacture of ammonia
for agricultural and other uses. Other major uses include
methanol production, petroleum refining, ore reduction, an-
nealing of metals, and the hardening of oils for the food.
23
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soap, lubricant, paint, and textile industries. Other uses
include cooling of electrical equipment in welding, in oxy-
hydrogen welding, and as a fuel. About 140,000 kkg (154,000
tons) were sold in the U.S. during 1972, but more was prob-
ably produced and used on-site.
Hydrogen Cyanide
Hydrogen cyanide is produced commercially by two processes.
One process (Andrussow process) involves the reaction of
air, ammonia, and natural gas (methane) in a catalytic
converter:
2NH3 + 302 + 2CH4 = 2HCN + 6H2O.
This reaction occurs at elevated temperatures over a
platinum catalyst, and the yield of hydrogen cyanide is on
tne order of 75 percent of theoretical. Other products and
product contaminants include residual ammonia and organic
nitriles. Dnreacted ammonia is removed from the products by
scrubbing with sulfuric acid. The crude cyanide is then
further purified by scrubbing with water and distillation of
the aqueous solution. The purified product is compressed
and liquefied for sale.
The other commercial source of hydrogen cyanide is as a by-
product from the production of acrylonitrile. Propylene,
ammonia, and air are reacted over a platinum catalyst to
form acetonitrile, acrylonitrile, and hydrogen cyanide. The
hydrogen cyanide is distilled off, compressed, and liquefied
for sale.
Most hydrogen cyanide production is captive to the
manufacture of intermediates for synthetic fibers or
plastics. The next largest usage is in the manufacture of
acrylate and methacrylate esters. It is a dangerous poison,
and the compressed gas is used as a fumigant for rodents and
insects. The amount sold commercially in the U.S. during
1971 was 128,000 kkg (141,000 tons).
Iodine
Iodine production in the United States arises from treatment
of natural brines in Michigan and Southern California. The
western oil well brines contain on the order of 65 mg/1
iodide. The oxidation of iodide for both types of brines is
effected by the addition of chlorine to clarified brine:
2NaI + C12 = 2NaCl + 12.
24
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Tne free iodine is stripped from the chlorinated brine by an
air stream, and the brine is pumped back to its source.
Iodine is absorbed from the air stream and reduced to
hydrogen iodide by sulfurous acid and then is chlorinated
bacK to the element. The liberated solid iodine is settled,
filtered, melted under sulfuric acid, cast into pigs,
crushed, and packaged.
The major uses of iodine are in the manufacture of potassium
iodide and other inorganic and organic compounds containing
iodine. Other uses include catalysis, lubrication of hard
surfaces, medicine, photography, and as a reagent in
analytical chemistry. The current U.S. commercial annual
sales are estimated to be 1,000 kkg (900 tons).
Iron Blues
The various ferrocyanide pigments are known under the
general name of iron blues. These include Prussian blue,
Chinese blue, bronze blue, etc. The generalized production
process, which varies somewhat from plant to plant, involves
the precipitation of ferrous sulfate-ammonium sulfate
solutions with sodium ferrocyanide to produce ferrous
ferrocyanide, followed by oxidation of this product to
ferric ferrocyanide by sodium chlorate. The generalized
reaction scheme is:
2FeS04 + NaiFe(CN)6.10H2O = Fe2Fe(CN)6 + 2Na2SO4
3Fe2Fe(CN)6 «• NaC103 = Fe4 (Fe (CN) 6) 3 * NaCl + Fe203.
The precipitated pigment is filtered, washed, dried, and
surface-treated to enhance pigment properties, and packed.
Iron blues possess good color and stability properties and
are relatively transparent. They are used for dip-coating
of foils and other bright metallic materials, for coloring
granules used on asphalt roofing, and various other
pigmentation applications. The U.S. production in 1971 was
4,900 kkg (5,400 tons).
Lead Oxide
Lead oxide, or litharge, is produced by the air oxidation of
lead, mixtures of lead and partially oxidized lead, or lead
suboxide in a furnace. The reactions are:
2Pb + O2 = 2PbO
2Pb20 + 02 = 4PbO.
25
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The product is cooled quickly to prevent formation of red
lead, milled, and packaged.
Nearly half of the litharge produced in this country is used
in-house by storage cattery manufacturers. It is also used
as a yellow pigment for ceramics, in varnishes, in petroleum
refining, and in the rubber industry. The amount sold in
the U.S. during 1971 was about 125,000 kkg (138,000 tons).
Lithium Carbonate
Lithium carbonate is produced by recovery from spodumene (a
lithium aluminum silicate ore) and by extraction from the
Trona (Searles Lake) brines of Southern California. In the
spodumene process the ore is concentrated by and roasted in
a kiln at 1,100°C to convert the a-spodumene to the softer
b-spodumene form. Tnis ore is ground and then treated with
sulfuric acid to form lithium sulfate, which is subsequently
leached from the ore residue with water. Lime and soda ash
are added to remove magnesium and calcium, respectively.
The purified solution is filtered, treated with sulfuric
acid to remove traces of iron and aluminum impurities, and
concentrated by evaporation. The lithium sulfate in
solution is then reacted with soda ash to precipitate
lithium carbonate by:
Li2SOJ» + Na2C03 = Li2CO3 + Na_SO4.
The carbonate product is washed, centrifuged, dried, and
packaged for sale.
Lithium carbonate production from Trona brine utilizes crude
burkeite precipitated from the initial partial evaporation
of the brine. Dilithium sodium phosphate is recovered by
flotation, filtered, and dissolved with sulfuric acid. The
reaction scheme is:
2Li2NaP04 + 2H2SCW = 2H3PO4 + 2Li2SOq + Na2SO4.
The resulting solution is evaporated to a suspension of
sodium and lithium sulfate crystals in concentrated
phosphoric acid. The solids are filtered out, and the
phosphoric acid sold. The salts are redissolved, and soda
ash is added to precipitate lithium carbonate by:
Li2S04 •«• Na2CO3 = Li2CO3 + Na2SO4.
Lithium carbonate is the most widely used lithium compound.
It is used in the production of lithium metal, enamels,
lithium-based lubricants, and other lithium compounds. It
26
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is also an additive to cryolite used in primary aluminum
production. The annual U.S. production of lithium carbonate
is estimated to be 12,250 kkg (13,500 tons).
Molyfedate Chrome Orange
The pigment known as molybdate chrome orange (or molybdenum
orange) is a mixed crystal of lead sulfate, lead chromate,
and lead molybdate. In the production process, a mixture of
sodium chromate and sodium molybdate is added to a solution
of lead nitrate or acetate to produce the precipitate. As
an example:
Na2CrO^ + Na2mo04_ * 2Pb (NO3) 2 = PbCr04 + 4NaNO3.
The U.S. production of molybdate chrome orange in 1971 was
10,300 kkg (11,400 tons).
Nickel Sulfate
The raw materials for the production of nickel sulfate
include metallic nickel and nickel oxide powders, spent
nickel plating solutions, and spent nickel catalysts and
residues. Although the process varies slightly depending on
the raw material, it basically involves reaction of the feed
with sulfuric acid. The reaction scheme with nickel oxide
is:
NiO + H2ISO4 = NiSOU + H2O.
The resulting nickel sulfate solution (after filtration, if
required) is then treated with sulfides, lime, sulfuric
acid, etc., to remove metallic impurities, and the resulting
muds are filtered out. The filtrate is sold as solution,
used in-plant, or sent to a concentrator stage where water
is removed. The solid nickel sulfate is recovered in a
crystallizer, and the mother liquor is recycled. The
crystals of nickel sulfate hexahydrate are classified,
dried, screened, and packaged.
Nickel sulfate is used in nickel plating, as a mordant in
dyeing and printing fabrics, and in blackening zinc and
brass. Total U.S. sales in 1971 were 15,200 kkg (16,800
tons) .
Commercial oxygen is produced, along with nitrogen, by the
distillation of liquefied air. Air is filtered, compressed^
freed of carbon dioxide and water, cooled by heat exchange
27
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and expansion distilled in a liquefier-rectifier column.
The product is gaseous oxygen warmed by heat exchange with
the incoming air, although liquid oxygen may be withdrawn
from the column provided additional heat is removed from the
system. Oxygen produced by the Linde Process via sieves is
not included in this study,
Most of the U.S. oxygen production arises from "on-site"
plants providing gaseous "tonnage" oxygen for use in the
steel industry. High-purity oxygen (99.5 percent) is
generally favored for medicinal use, and production of
ammonia, acetylene, ethylene oxide, and missile oxidizers.
The use of liquid oxygen is rapidly increasing, but the
major use industries utilize the gaseous form because of the
more economical heat balance. Commercial oxygen production
for sale in the U.S. during 1972 totalled about 13,400,000
kkg (14,700,000 tons).
Potassium Chloride
Potassium chloride is obtained from the Trona brines of
California and from the sylvite (NaCl-KCl) ore deposits of
New Mexico. In the sylvite process the ore is mined,
crushed, screened, and wet-ground in brine to dissolve most
of the soluble salts. Clay is removed by settling, as are
the other undissolved materials in a separate step. The
brine, saturated in sodium chloride, is fed to a flotation
cell where air is passed through the solution (to which
flotation agents such as tallow amines, polyalkyl glycol,
starch, etc. have been added) in order to carry sodium
chloride into the froth. The potassium chloride brine is
then vacuum-crystallized, and the potassium chloride
crystals are centrifuged, dried, screened and packaged.
Trona brine and mother liquors from other processes in the
complex are filtered, heated, and evaporated to remove crude
sodium chloride and burkeite (see lithium carbonate). The
solution then primarily contains borax and potassium
chloride. The potassium chloride is removed by
crystallization and subsequent decantation of the borax
solution. The potassium chloride crystals are centrifuged,
dried, and packaged.
The Trona brines have been used to recover potassium
chloride for over 50 years, but the major U.S. production
comes from the Carlsbad (New Mexico) sylvite mines'. Over 90
percent of the U.S. production is sold for use as
fertilizer, and this is called muriate of potash. The
various grades are based on their potash (potassium oxide)
equivalent. Other uses include medicine (prevention and
28
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treatment of hypokalemia), as a sodium chloride substitute
for table use, and applications photography and in
analytical chemistry. The U.S. production in 1971 was
2,540,000 kkg (2,800,000 tons).
Potassium Iodide
Potassium iodide is produced by the reaction of iodine with
potassium hydroxide in solution according to:
12 + 6KOH = SKI + KIO3 + 2H2O.
The iodate precipitates out and is removed as a by-product.
The iodide solution is evaporated to dryness and fused in a
gas-fired furnace to decompose residual iodate. The fused
iodide is redissolved in distilled water, and barium carbo-
nate, hydrogen sulfide, ferrous iodide, and carbon dioxide
gas are added to precipitate impurities and adjust the pH of
the solution. The solution is filtered and fed to crystal-
lizers, from which the potassium iodide crystals are centri-
fuged, dried, screened, and packaged. The mother liquor
from the crystallizers is recycled.
Potassium iodide is used in photographic emulsions, in
animal feeds, and as an additive to table salt. It also has
a number of medical uses. The U.S. production in 1971 was
810 kkg (890 tons) .
Silver Nitrate
Silver nitrate is produced commercially by the treatment of
metallic silver with nitric acid. The generalized reaction
is:
2Ag + 2HNO3 = 2AgNO3 + H2.
However, in the production process, mixed oxides of nitrogen
also produced. These are air-oxidized to nitrogen dioxide
and then to nitric acid.
The silver nitrate solution from the dissolver is evaporated
and sent to a crystallizer where silver nitrate crystals are
recovered. The crystals are centrifuged, redissolved, and
recovered by evaporation, crystallization, and
centrifugation. The purified crystals are then dried and
packaged..
Silver nitrate has many uses even though it is not produced
in large quantities. These uses include photography, manu-r
facture of other silver salts, manufacture of mirrors,
29
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silver plating, inks, coloring porcelain, as a chemical
reagent, and in medicine as an antiseptic and astrinij£nt.
Sales from U.S. production totaled 3,100 kkg (3,400 ttms)
in 1971.
Sodium Fluoride
Sodium fluoride is produced in this country by reacting
hydrogen fluoride with soda ash and by reacting sodium sili-
cofluoride with caustic soda. The respective reactions for
those two processes are:
2HF + Na2C03 = 2NaF + H2O + CO2
Na2SiF6 •«• 6NaOH = 6NaF + Na2SiO3 + 3H2O.
In the first process listed, anhydrous hydrofluoric acid
(hydrogen fluoride) and soda ash are reacted, and hydrogen
fluoride fumes and carbon dioxide are scrubbed with a soda
ash solution. The product from the reactor is a slurry of
sodium fluoride which is vacuum filtered to recover the
fluoride. The product is then dried and packaged.
The second process typically involves a batch reaction in
aqueous solution. The sodium fluoride precipitate is fil-
tered out, dried, collected in a cyclone, and packaged for
sal«» ^
Perhaps the best known use of sodium fluoride is in the
fluoridation of drinking water to preserve teeth. Other
uses include insecticides and disinfecting agents, in
enamels and glasses, electroplating, in fluxes, paper
manufacture, and the frosting of glass. Commercial sales
from U.S. production in 1971 totaled 5,000 kkg (5,500 tons).
Sodium Silicofluoride
Sodium silicofluoride is produced by precipitation from
fluorosilicic acid through addition of sodium chloride or
soda ash. The fluorosilicic acid from phosphoric acid
manufacture is a typical raw material. The sodium chloride
source is rock salt or brine. The use cf soda ash instead
of sodium chloride is becoming more favored because of tne
waste disposal problems associated with hydrochloric acid
formation. Caustic soda may be used instead of soda ash.
Process equations using sodium chloride and soda ash
respectively, are:
H2SiF6 + 2NaCl = Na2SiF6 * 2HC1
30
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H2SiF6 + Na2CC3 = Na2SiF6 + H20 + CO2.
The precipitated sodium silicofluoride crystals from the
reactor are settled, filtered or centrifuged from the
product solution, washed, dried, and packaged.
Sodium silicofluoride is used in the production of sodium
fluoride (see sodium fluoride), as an insecticide, as a
laundry product, as a fluxing and opacitying agent, and as a
protective agent for light metals. Sales from O.S. produc-
tion in 1971 totalled 54,800 kkg (60,400 tons).
Stannic Oxide
Stannic oxide is produced by the reaction of tin metal with
caustic soda (and oxidation) to form sodium stannate. This
is followed by reaction of the stannate with sodium
bicarbonate to form stannic oxide hydrate, and dehydration
of this material to stannic oxide. The overall reaction
scheme is:
Sn + 2NaOH <• 02 + 2H2O = Na2Sn(OH)j>
Na2Sn(OH)6 + 2NaHCO3 = Sn (OH) 4 + 2Na2CO3 + 2H2O
Sn(OH)4 heat = SnO2 + 2H2O.
The tin raw material is either primary tin metal or scrap
tin (tin cans and bearing scrap). For the latter, the tin
can scrap is detinned in a caustic soda bath, and the steel
scrap is recovered,, washed, and sold. Various treatments
are used to remove impurities from the solution, including
removal of lead and zinc by sodium hydrosulfide,
precipitation of alumj num by sodium silicate, etc. The
sodium stannate evolution is then filtered. For either raw
material the remainder of the process is similar. The
solution is treated with sodium bicarbonate to form the
stannic oxide hydrate, neutralized with acid, and spray
dried to remove the hydrate. The hydrate is dehydrated in a
kiln, ground, and packaged for sale.
Stannic oxide is used to polish glass and metals, in the
manufacture of glass and other ceramics (coloring agent), in
printing and dyeing of fabrics, and in fingernail polishes.
The U.S. production of stannic oxide during 1971 was 415 kko
{458 tons) . ^
Zinc Sulfate
31
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Zinc sulfate is produced by the acidulation of zinc oxide
with sulfuric acid:
ZnO + H.2SO4. = ZnSOU + H20.
Tne raw material is zinc oxide produced as discussed in the
previous section, or bag house fujie (crude zinc oxide) from
primary lead production. The zinc oxide is leached with
sulfuric acid and filtered to remove insolubles. The solu-
tion is treated with zinc dust to precipitate metallic
impurities, filtered, evaporated to dryness, and sold as the
monohydrate.
Zinc sulfate is used in fabric printing, in preserving wood
and hides, in zinc electrodeposition, in paper bleaching,
and in the manufacture of other zinc salts. The U.S. sales
in 1971 were 38,300 kkg (42,300 tons). Zinc sulfate pro-
duction has been decreasing over the past few years.
Zinc Yellow
Zinc yellow pigment is a complex mixture whose composition
includes zinc, potassium, and chromium. Of the two types of
zinc yellow, the low chloride-sulfate type is prepared by
first reacting zinc oxide with potassium hydroxide, then
adding the chrornate as a solution of potassium
tetrachromate. High chloride zinc yellow is made by
reacting zinc oxide with hydrochloric acid and sodium
dichromate to produce a zinc yellow slurry. The solids are
removed by filtration, dried, milled, and packaged for sale.
Zinc yellow is most often used as a primer (inhibitive pig-
ment) for metals, particularly steel and aluminum. It is
also used in mixed paints. The U.S. production in 1971 was
5,050 kkg (5,600 tons).
Production of Selected Inorganic Chemicals
The production or sales figures were derived from the Bureau
of Census (U.S. Department of Commerce) publications (9,10) .
These figures are tabulated in Table 3.
32
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CO
CJ
TABLE 3
197! U.S. PRODUCTION OF SIGNIFICANT INORGANIC CHEMICALS (METRIC TONS)
Chemical Production Chemical Production
Aluminum Fluoride
Ammonium Chloride
Ammonium Hydroxide
Barium Carbonate
Borax
Boric Acid
Bromine
Calcium Carbonate
Calcium Hydroxide
Carbon Dioxide
Carbon Monoxide
Chrome Green
Chrome Yellow and
Orange
Chromic Acid
Chromic Oxide
Copper Sulfate
Cuprous Oxide
Ferric Chloride
Ferrous Sulfate
Fluorine
Hydrogen
Hydrogen Cyanide
Iodine
Iron Blues
143,000
25,000(est.)
41,000
55,000
525,000
95,400
38,000
165,000
38,000(1970)
,220,000(1972)
135,000(est.)
2,450
18,200
19,400
6,000
30,500
1,870
68,000
147,000
Unknown
140,000(1972)
128,000
1,000 (est.)
4,900
Lead Oxide
Lithium Carbonate
Manganese Sulfate
Molybdate Chrome
Orange
Nickel Sulfate
Nitric Acid (Strong)
Nitrogen
Oxygen
Potassium Chloride
Potassium iodide
Potassium Permanganate
Silver Nitrate
Sodium Bisulfite
Sodium Fluoride
Sodium Hydrosulfide
Sodium Hydrosulfite
Sodium Silicofluoride
Sodium Thiosulfate
Stannic Oxide
Sulfur Dioxide
Zinc Oxide
Zinc Sulfate
Zinc Yellow
125,000
12,250 (est.)
33,500
10,
15,
162,
6,100,
13,400,
2,540,
3.
45,
5,
27,
37,
54,
22,
86,
200,
38,
5,
300
200
000
000 (1972)
000 (1972)
000
810
000
100
400
000
000
000
800
800
415
500
000
300
050
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SECTION IV
INDUSTRY CATEGORIZATION
INTRODUCTION
For the purpose of establishing effluent limitations
guidelines for existing point sources and standards of
performance for new sources, the inorganic chemicals
manufacturing category has been segmented into subcategories
based on the specific inorganic product manufactured. In
cases where one chemical is produced by dissimilar
processes, the product subcategory has been further
subdivided. Although similar waste water constituents may
be generated from various product groupings and may be
treated to similar concentrations,, water requirements are
specific for each chemical manufacturing process.
Guidelines based on production volume must reflect this
difference.
INDUSTRY CATEGORIES
The separation of each product into individual subcategories
simplifies the application of the effluent guidelines and
standards of performance by providing unambiguous direction
as to the application of a standard to a given point source.
This is critical because of the great variety of product mix
in existing facilities. The substantial advantage of
clarity outweighs any technical advantages of product
grouping.
FACTORS CONSIDERED
In developing effluent limitations and standards of
performance, it was necessary to examine numerous factors to
determine whether additional segmentation of the industry is
justified. The factors considered include:
(a) Waste water constituents
(b) Treatability of waste waters
(c) Manufacturing process
(d) Plant age
(e) Plant size
(f) Product mix
(g) Raw materials
(h) Air pollution control devices
(i) Geographical location.
35
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A summary of the rationale employed in determining whether
these factors necessitate further subcategorization is
presented below.
(a) Waste water constituents.
The selected subcategorization scheme reflects gross
differences in the raw waste loads generated from different
chemical manufacturing processes. While it is recognized
that the character and quantities of waste water pollutants
may vary within a product subcategory, this difference is
not sufficient to justify additional segmentation. When two
different processes used to manufacture the same chemical
generate dissimilar waste water constituents, they have been
considered individually.
(b) Treatability of waste waters.
The treatability of waste water is determined largely by the
volume of waste water and by the type of pollutants present.
Thus, the above discussion on waste water constituents is
applicable here.
(c) Manufacturing process.
Establishing subcategories based on product manufactured
generally reflects differences between various manufacturing
processes. The product subcategories are further segmented
if two dissimilar manufacturing processes are commonly used.
(d) Plant age.
The relative age of plants within a product subcategory are
determined by obsolescence due to process or equipment
changes and not physical age. Hence, plant age is not an
appropriate basis for subcategorization. No correlation
between plant age and effluent quality is evident from plant
data.
(e) Plant size.
Plant size generally has little effect on the quality of
waste water generated from various chemical manufacturing
processes. Although treatment costs per unit of production
are somewhat lower when large quantities of water are
treated, this difference is not sufficiently great to
warrant further segmentation of the industry.
(f) Product mix.
36
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Chemical plants vary greatly in terms of the number and
types of products manufactured. More treatment options and
a greater reuse potential exist in plants manufacturing many
chemicals. However, treatment alternatives exist for small
and single-product plants, such that additional
subcategorization is unnecessary.
(g) Raw materials.
Different raw materials are obviously used to manufacture
different products. This difference is reflected in the
selected subcategorization scheme. However, within a
product subcategory raw materials of varying degrees of
purity are used. Because ore beneficiation and cleaning may
be used to treat impure ores, raw material quality does not
justify further segmentation of the industry. In certain
cases different raw materials do not alter the treatability
of the process effluent,
(h) Air pollution control devices.
The type of system used to control air pollution will have
an effect on the water treatment requirements of a given
plant. Wet scrubbing solutions are the only source of waste
water in some chemical manufacturing processes. In general,
scrubbing solutions may be treated and recycled or reused.
In some cases, this solution may be sold as a weak product
solution. Product recovery justifies conversion to a dry
bag collection system for some manufacturing processes.
Because of the options available to economically treat,
sell, recycle, reuse or eliminate scrubbing solutions, it
was considered unnecessary to subcategorize according to
methods of air pollution control.
(i) Geographical location.
Geographical location is important in analyzing the
feasibility of various treatment alternatives. Evaporation
ponds are functional only in areas where net evaporation
exceeds rainfall. The possibility of ground water
contamination may preclude the use of unlined holding and
settling ponds in many locations. The location of a plant,
therefore, is an important factor in selecting the
appropriate treatment technologies for a specific plant.
Because alternative treatment systems are available to
.ccommodate differences in climate, geology, etc.,
additional subcategorization based on plant location is not
justified.
37
i
-------
The product snbcategories are shown below with process
subdivisions where required:
Aluminum Fluoride
Ammonium Chloride
(a) Anhydrous
(b) Solvay By-product
Ammonium Hydroxide*
Barium Carbonate*
Borax
Boric Acid
(a) Trona Process
(b) Ore Mined Borax
Bromine
Calcium Carbonate
(a) Milk of Lime Process
(b) Solvay Process
Calcium Hydroxide
Carbon Dioxide*
Carbon Monoxide and By-product Hydrogen
Chrome Pigments and Iron Blues
Chromic Acid
Copper Sulfate
(a) Pure Raw Material
(b) Recovery Process
Cuprous Oxide*
Ferric Chloride
Ferrous Sulfate*
Fluorine
(a) Liquid HF Electrolysis Process
(b) Fused Salt Electrolysis Process*
Hydrogen
Hydrogen Cyanide
(a) Acrylonitrile By-product
(b) Andrussow Process
Iodine
Lead Monoxide
Lithium Carbonate
(a) Trona Process
(b) Spodumene Ore Process
Manganese Sulfate*
Nickel Sulfate
(a) Pure Raw Materials
(b) Impure Raw Materials
Nitric Acid (Strong) *
Oxygen and Nitrogen
Potassium Chloride
Potassium Iodide
Potassium Permanganate*
Silver Nitrate
38
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Sodium Bisulfite*
Sodium Fluoride
Sodium Hydrosulfide*
Sodium Hydrosulfite*
Sodium Silicofluoride
Sodium Thiosulfate*
Stannic Oxide
(a) Dry Process
(b) wet Process*
Sulfur Dioxide*
Zinc Oxide*
(a) Dry Process
(b) Wet Process
Zinc Sulfate
*Reserved.
39
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SECTION V
WATER USE AND WASTE CHARACTERIZATION
I!fTRODUCTION
Phis section discusses the specific water uses in the
Significant Inorganic Products Segment of the Inorganic
Chemicals Manufacturing Industry, and the amounts of process
waste materials contained in these waters. The process
wastes are characterized as raw waste loads emanating from
specific processes used for the manufacture of the chemicals
involved in this study. The raw waste loads are given in
terms of kilograms per metric ton of product produced
(pounds per short ton). The specific water uses and amounts
are given in terms of liters per metric ton of product
produced (gallons per short ton) for each of the plants
contacted in this study. The treatments used by the
chemical plants studied are specifically described and the
amount and type of waterborne waste effluent after treatment
is characterized.
The historical data base which was utilized for this study
was verified through a verification sampling program
employing approved EPA analytical techniques.
ANALYTICAL LABORATORY WASTES
The effluent limitations guidelines do not contain
allowances for analytical laboratory wastes because they are
not related to a factor of production and because they
result from a planned, routine activity which lends itself
to proper disposal of pollutants. For example, the residual
samples can be returned to the process streams. The spent
analytical reagents may be disposed of in a similar manner
or routed to a form of disposal along with plant sludges,
solid wastes, or sanitary wastes. In any event, the
quantity of waste should be relatively insignificant when
Compared to the plant effluent waste loads.
SPECIFIC,WATER USES
Water is used in the inorganic chemical processing plants
/or six principal purposes tailing under three major
laracterization headings. The principal water uses are:
I) cooling water—noncontact cooling water
2) process water—contact cooling or heating water
41
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contact wash water
transport water
product and dilution water
3) auxiliary processes water.
The noncontact cooling water is defined as tnat cooling
water which does not come into direct contact with any raw
material, intermediate product, by-product or product used
in or resulting from the chemical production. The process
water is defined as that water v,nich, during the
manufacturing process comes into direct contact with any raw
material, intermediate product, cy-prcduct or product used
in or resulting from the chemical production.
Auxiliary process water is defined as that used for
processes necessary for the production of a chemical but not
contacting the process materials. For example, water
treatment regeneration is an auxiliary process.
The quantity of water usage for plants in this industry
generally ranges from 1,000 to 180,000,000 I/day (264 to
47,500,000 gal/day). In general, the plants using very
large quantities of water use it for once-through cooling,
barometric condensers or brine extraction.
Non-Contact Cooling Water
Many chemical processes operate more quickly or more
efficiently at high temperatures, or generate heat during
exothermic reactions. Cooling water is often used to
control or reduce these temperatures. If the water is used
without contacting the reactants, such as in a tube-in-shell
heat exchanger or trombone cooler, then the water will not
be contaminated with process waste water pollutants. The
water contacts the reactants, then contamination of the
water results and the waste load increases. Probably the
single most important process waste control technique,
particularly with regard to feasibility and economics of
subsequent treatment, is segregation of noncontact coolina
water from contact cooling and process water.
The noncontact cooling water in the industry is generally of
two types. The first type is recycled cooling water which
is cooled by cooling towers or spray ponds. The second type
is once-through cooling water whose source is generally a
river, lake or tidal estuary. This water is usually
returned to the source from which it was taken.
42
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Contact Cooling or Heating Water
This water comes under the general heading of process water
because it comes into direct contact with process reactants.
Primary examples of this type of water usage are quenching,
slurrying and use in barometric condensers. Water is
required in very large quantities for barometric condensers
which are used to provide,reduced pressure for the operation
of multiple effect evaporators. For a large triple-effect
evaporator such as that used for salt evaporation, flows of
3,800 to 41,600 cu m/day (1 to 11 mgd) are not unusual. A
waste effluent problem with the barometric condenser usage
arises from the product vapors and carryover from the last
effect (stage) of the evaporator which are entrapped in the
flow of condenser water. Because this condenser water is
normally used in high volume, it is usually discharged
without treatment.
Other direct contact cooling or heating water usage such as
that for contact steam drying, steam distillation, pump and
vacuum seals, etc., is generally of much lower volume than
the barometric condenser water and is generally easier to
treat.
Contact Wash Water
This water also comes under the heading of process water
because it comes into direct contact with either the raw
material, reactants or products. Examples of this type of
water usage are ore washing to remove fines, filter cake
washing to remove entrained particles, cleansing of
insoluble product vapors, and absorption process wherein
water is reacted with a gaseous material to produce an
aqueous solution. Waste effluents can arise from all these
washing sources due to the fact that the resultant solution
or suspension may contain impurities or may be too dilute a
solution to reuse or recover.
Transport Water
Water is often used in the inorganic chemical industry for
transporting reactants or products to various unit
operations either in solution, suspension or slurry form.
Examples of this are soda ash waste liquor and solution-
mined salt or brine. Water is pumped into a salt cavity at
the rate of 3900 1/kkg (936 gal/ton) of salt. The salt is
dissolved, and the resulting brine is forced to the surface
under pressure where it can be fed to evaporators to produce
dry salts or fed to extractors where it is used to produce
bromine and iodine. Wastes resulting from these types of
43
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operations are generally dilute solutions or suspensions
which could be reused upon concentration or could be
returned to the source. In cases where transport water is
carrying a solid product, it normally is separated from the
product by filtration, evaporation, or drying. The
resultant liquor or condensate generally contains dissolved
product, reactants or impurities, and often is discharged.
Product Water
The product water generally is that which comes in contact
with the product and stays with the product as an integral
part. Typical examples include acidulation water used for
nickel sulfate manufacture and water used in absorption
towers. Likewise, water may be added to a highly
concentrated product to form a more dilute product. The
source of these waters is generally fresh water supplies,
steam condensate, dilute product streams, or a combination
of these sources. In general, waste loads from this water
usage are minimal.
Miscellaneous Water Uses
These water uses vary widely among the plants with general
usage for floor washing and cleanup, safety showers and eye
wash stations, sanitary uses, and storm runoff. The
resultant streams are either not contaminated or only
slightly contaminated with wastes. The general practice is
to discharge such streams without treatment except for
sanitary waste. In instances where process residues—epllect
where they can be washed away by storm waters, as
example dusts on the exterior of process buildings, storm
water runoff can constitute a serious contamination problem.
Auxiliary Water
This water is used by the typical plant for auxiliary
operations such as ion exchange regenerants, make-up water
to cooling towers with a resultant cooling tower blowdown,
make-up water to boilers with a resultant boiler blowdown,
equipment washing, storage and shipping tank washing, and
spill and leak washdown. The water effluents from these
operations are generally low in quantity but highly
concentrated in waste materials.
The waste effluent from recycled cooling water would contain
water treatment chemicals in cooling tower blowdown. The
waste effluent from the once-through cooling water would
contain water treatment chemicals which are generally
discharged with the cooling water. The cooling water tower
44
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blowcown may contain phosphates, nitrates, nitrites,
3uifa~es, and chromates.
Water treatment chemicals may consist of alum, hydrated
li:ne, or alkali metal ions (sodium or potassium) arising
from ion exchange processes. Regeneration of the ion
exchange units is generally accomplished with sodium
chloride or sulfuric acid depending upon the type of unit
employed.
PROCESS WASTE CHARACTERIZATION
The chemical products are discussed in alphabetical order in
this section. For each chemical product the following
information is given:
—a short description of the differences in the
processes at the plants studied and pertinent
flow diagrams;
—raw waste load data per unit weight of product;
—water consumption data per unit weight of product;
— specific plant waste effluents found and the post-
process treatments used to reduce the effluent
contaminant load;
—significant differences from plant data where found
in verification measurements.
ALUMINUM FLUORIDE
Process waste information is presented herein for two plants
of roughly equivalent production. The production of this
material in the U.S. is geographically limited to the
Louisiana-Texas region. The two plants cited here account
for approximately three-fourths of the U.S. production. A
third plant of significant production is known to have no
process effluent.
Process Description
Hydrated alumina and hydrogen fluoride are reacted to form
alu-.inum fluoride, which is then cooled and conveyed to a
storage area for packing and shipment. The gases and dusts
from the reactor at plant 233 are treated first with dry
collection cyclones to recover product, which is recycled.
45
-------
and then by wet scrubbers. The process flowsheet is shown
in figure 1. The process reaction is :
A1203.3H20 + 6HF = 2A1F3 + 6H2O.
The process practiced at plant 230 differs in t'-at a
hydrogen fluoride production unit is integrated within" <-ne
process unit for production of aluminum fluoride and all of
the waste streams from the aluminum fluoride procr-s^ ^id-
are utilized in adjoining facilities.
At Plant 230, hydrogen fluoride gas is generated bv the
reaction of sulfuric acid with fluorspar (calcium fluorid-)
in a kiln reactor. The calcium sulfate and unreact-d
materials from the reactor are slurcied with water and cent
to a neutralization system where hydrated lime is used to
neutralize and precipitate excess sulfate and fluoride Trj9
tail gases from the hydrogen fluoride hi In reactor a-e
scrubbed with salt water and. discharged to the lim-=>
neutralization system along with scrubber wastes from th=
water scrubber on the fluorspar dryer. The wastes from the
neutralization treatment are sent to an artificial lagoon
tor settling and the overflow is then discharged. Up to
this point, the operation is fairly topical of" a
hydrofluoric acid plant without the associated unit
operations for cooling and purification of merchant grade
acid. r
The generated hydrogen fluoride gas is then introduced into
a reactor together with dried hydrated aluminum oxide (alum-
ina tnhydrate) . The product aluminum fluoride is recovered
from the reactor, cooled in a noncontact heat exchanger
then transported to a storage hopper for loading. The tail
gases from the aluminum fluoride reactor are scrubbed with a
sodium carbonate solution, which is subsequently used in an
adjoining facility. Water scrubbers are used on th«
hydrated aluminum oxide dryer and the aluminum fluoride
loading and packaging operations. The scrubber wastes are
also used in adjoining facilities. The process flowsheet
for this portion of the plant 230 process is shown in Figure
^ •
Raw Waste Loads
The main process reaction generates no by-product raw wast"
material. Process raw wastes are generated by the various
gas scrubbers and by leaks and spills. The average ani
range values for these two plants are:
46
-------
WATER
i
CYCI ONF ib ^PRIIRF
VENT
JER »•
t 1
HYPRATm Al HMiN A •">«... «KiM>|ia
HYDROGEN FLUORIDE: • * 93-
SCRUBBER WASTE WATER
PRODUCT
AND STORAGE
——fis* PRODUCT
•f *
NONJCONTACT
COOLING WATER
FIGURE i
ALUMINUM FLUORIDE MANUFACTURE AT PLANT 233
WATER VENT SOLUTIO^ VENT CONTACT COOLING WATER WATER VENT
i t * t 1 ........ i t
SHRI IRRFR .^-SCRUBBER orr»i inOFR ^
VACUUM '
PUMP
^ WATER
WASTE SCRUBBER
SCRUBBER
'^ WASTE
Ii > SCRjsBER A
HYDROGEN^ ^TAIL GAS WASTE T
FLUORIDE 1 •* NON- CONTACT COOLING WATER
HEAT
EXCHANGER '
LOADING
PACKAGING
in ••gi 'PRODUCT
FIGURE 2
ALUMINUM FLUORIDE MANUFACTURE AT PLANT 230
-------
waste material plant 233 plant 230
HF 20 (40)
H2SiF6 {as HF) 12 (24)
10-15 (20-30)
A1F3 9 (18) 30 (60)
6-12 (12-24)
H2S04 (as S04=) 60 (120) 50 (100)
45-90 (90-180)
A1203 9 (18) 20 (40)
6-12 (12-24)
spillage dusts 5 (10) not given
containing CaF,
A12O3 and A1F3
The raw waste values of A1F3_ given above for plant 233 does
not include an unknown amount from the wet scrubbers on the
loading operations. The si1icofluorides and sulfates
originate as impurities in the hydrogen fluoride raw
material stream,
Plant Water Use
Water is used in these plants for cooling, scrubbing, and
for vacuum pump seals. The water of hydration of the
alumina raw material plus the water generated in the process
reaction, in total amounting to 644 1/kkg of aluminum
fluoride (154 gal/ton) is evaporated in the reactor. The
various modes of water consumption at these two plants are:
1/kkg
of product (gals/ton)
consumption plant 233 plant 230
evaporated (calculated) 644 (154) 644 (154)
scrubbers 17,100 (4,100) 12,000 (2,500) est.
contact cooling (seals) - 12,400 (2,970)
noncontact cooling- 196 (47)
discharge
The use of a cooling tower and recirculation results in the
smaller noncontact cooling waste discharge of plant 233
compared to 230.
Haste Water Treatment
At plant 233 all scrubber waters are passed through a
settling lagoon prior to discharge. Cooling tower tlowdown
is directly discharged.
48
-------
At plant 230 the waste water streams attributable to
aluminum fluoride production require no treatment because
they are utilized in adjoining facilities.
Plant Effluents
The average combined scrubber discharges of plant 233 after
treatment are given as follows:
calculated kg per metric ton
concentration (mq/1) of product (lb/ton)
TSS 9 0.110 (0.221)
fluoride 1000 12.3 (24.6)
silica 300 3.7 (7.4)
The above calculated amount of fluoride is somewhat in
excess of the average raw waste load figure given. The pH
of this effluent is below 7 and the range of TSS values is
5-100 mg/1. No waste water effluents are discharged from
this operation at plant 230 because the plant enjoys the
unique advantage of having a complex where all the waste
streams can be utilized in adjoining facilities.
AMMONIUM CHLORIDE
Ammonium chloride is manufactured at one major facility from
Solvay process waste streams. The pertinent data for this
plant is given herein. Another process for the manufacture
of ammonium chloride involves the reaction of anhydrous
ammonia with hydrog*en chloride gas. This process uses no
water and therefore has no discharge of process waste water.
The rest of the U.S. production is by-product from processes
for other chemical products.
Process Description
Ammonium chloride-containing liquor from the Solvay soda ash
process is first filtered to remove suspended materials and
then partially evaporated to remove residual ammonia and
carbon dioxide. The liquor is cooled in a series of vacuum
flash coolers until ammonium chloride separates out by
crystallization. The product is recovered by
centrifugation. The mother liquor from which the material
was recovered as well as the evaporator condensates are
returned to the soda ash plant for recovery of residual
ammonium values. Figure 3 is a flow diagram of this process
as practiced at plant 333.
Raw Waste Loads
49
-------
FILTRATE FROV SCCA ASH
•*
PREHEAT
BACKWASH
FILTER
FLOOR
WASHINGS
I
EVAPORATE
11
I
FLASH COOL
J
1 — ^
SPENT
i ini IHR
i_iwuvjr\
STORAGE
"-i
j MOTHER LIQUOR'' 1
TO SODA ASH
PROCESS
DUST
COLLECTOR
«• — i
t
'AATER
FLASH DRYER
i
FLUID-BED
DRYER
4
OVERSIZE
'.VATER
*
DUST
COLLECTOR
SCREEN
t? '
PACK
1
PRCCUC
TO
SOOA ASH
PROCESS
CONDENSER
NCN -CONTACT
CONDENSATE
CONDENSERS
CONTACT
COOLING
WASTE
1
P'.O!
I ! "W
CHLORiDE
SODA A^
-------
The process raw wastes consist of ammonia from the condenser
discharges and unrecovered sodium and ammonium chlorides in
the mother liquor. Most of these wastes are returned to the
soda ash facility for recovery of ammonia values.
waste
material
ammonia
sodium
chloride
ammonium
ch lor ide
filter
muds
sludges
source
condenser
discharge
raw material
unrecovered
product
process
filters
tank
cleanings
kg per metric ton
(Ibs/tonl
av. 3.5 (7)
max. 4.5 (9)
av. 800 (1600)
av. 600 (1200)
not known
not known
disposition
discharge to flume
containing mill
water
recycle to soda
ash
recycle to soda
ash
to settling ponds
to settling ponds
Since the process consists of extraction of a soda ash pro-
cess waste material with recycle of the remainder back to
the soda ash process, no net process raw waste materials are
generated by this process, except for filter aids added
specifically for this process and the ammonia carry-over in
the barometric condenser discharge.
All the above raw wastes entered the process with the Solvay
waste stream raw material with the exception of the filter
aids.
Plant Water Use
Water is used for cooling in plant 333 at a rate of 226,000
1/kkg of ammonium chloride product (54,200 gal/ton) to a
maximum amount of 466,200 1/kkg (111,800 gal/ton). Of this,
the amount that has been involved in contact cooling is
171,000 1/kkg (40,900 gal/ton) on the average. Other water
intakes to the plant process include that from the raw
material Solvay filter liquor plus a total of 9,500 1/kkg of
municipal and river water (2,280 gal/ton). The consumption
of this is as follows:
consumption
contact cooling discharge
process water discharge
boiler feed
sanitary
ash and cinder sluice
liters per metric ton (gal/ton)
171,000(40,900)
930 (220)
5,560 (1,360)
220 (53)
1,780 (430)
51
-------
water purification muds m
cooling (noncontact) 2,690 (64 0)
The process wastes streams are returned to the soda ash pro-
cess for ammonia recovery. The contact cooling water dis-
charge, which contains ammonia, is sewered.
Waste Water Treatment
Process wastes are returned to the soda ash process. The
waste carryovers in the condenser streams consist of ammonia
and ammonium salts. The alkaline nature of this waste,
however, results in precipitation of salts contained in the
cooling water discharged by other portions of the complex
(common sewer system).
Effluent
The waste materials in the condenser effluent streams are
principally ammonia and ammonium salts. These wastes appear
in the cooling water effluent as ammonia and ammonium
compounds. The amounts of these wastes expressed as ammonia
(NH3) are 4.4 kg/kkg (8.8 Ib/ton). These wastes are only a
very small portion of the entire Solvay complex discharge
which contains large amounts of other inorganic chemical
wastes.
BORAX
The U.S. production of borax is carried out in the desert
areas of California by two processes: the mining and
extraction of borax ore and the Trona process. This latter
process is discussed in detail in the section on Trona. The
mining and extraction process accounts for about three-
fourths of the estimated U.S. production of borax.
Process Description
Borax is prepared by extraction from an ore which is an im-
pure form of sodium tetraborate decahydrate (borax). The
ore is crushed, dissolved in water and recycled mother
liquor. The solution is fed to a thickener where the
insolubles are removed and the waste is sent to percolation-
proof evaporation ponds. The borax solution is piped to
crystallizers and then to a centrifuge, where solid borax is
recovered. The borax is dried, screened and packaged and
the mother liquor is recycled to the dissolvers. A process
flow diagram is given in Figure 4.
Raw Waste Load
52
-------
BORAX ORE
I
CRUSHER
VYATER-
/ RECYCLE
/MOTHER
LIQUOR
man
WATCH
I
DISSOLVER
I
THICKENER
I
CRYSTALLIZER
I
CENTRIFUGE
I
DRYING
AND
SCREENING
VWTER
CONTACT COOLMG
-VENT
PRODUCTS
FIGURE 4
BORAX PRODUCTION FROM ORE
53
-------
Wastes from this process at plant 390 consist of 800 kkg of
insolubles/kkg of borax product (1,600 Ib/ton) from the ore.
This amount is independent of startup and shutdown
operation.
Plant Water Use and Treatment
Fresh water consumption at the plant 390 amounts to 2,840
1/kkg (680 gal/ton). An additional 835 1/kkg (200 gal/ton)
enters via the ore. Most of the cooling water is recycled
and all of the process waste waters are fed to evaporation
ponds. The consumption of water is:
liters per metric ton
water consumption of product (gal/ton}
process consumed 668 (160)
process waste discharge 1,627 (390)
contact cooling discharge 313 (75)
noncontact cooling discharge 104 (25)
boiler feed 296 (71)
sanitary 25 (6)
road conditioning 271 (65)
not otherwise allocated 367 (88)
total consumption 3,671 (880)
Waste Water Treatment
Present treatment consists of percolation-proof evaporation
ponds.
Effluent and Disposal
There is no plant effluent. The concentrations (in mg/1) of
pollutants in the intake water and the waste water sent to
the evaporation ponds are:
intake water to evaporation ponds
alkalinity (total) 188 10,830
hardness (total) 3.5 1,145
(CaCO3j
chloride 176 3,100
nitrogen (NO3-) 3.5 2.8
COD 5 480
BOD 5 81
BORIC ACID
54
-------
Boric acid is universally made by reacting borax and
sulfuric acid. The U.S. sources of borax production are the
desert areas of California. The boric acid production is
tnerefore located in that vicinity. Approximately 70
percent of the U.S. production of boric acid is based on
borax from mined ore. The rest is from borax extracted from
lake brines in the Trona process which is discussed in the
section on Trona. The discussion below is based on a large
plant producing boric acid from mined borax.
Process Description
Sodium borate pentahydrate and sulfuric acid are reacted and
the resulting slurry is vacuum filtered to recover boric
acid. The filtrate is used for recovery of by-product
sodium sulfate. The solid boric acid is dissolved in water,
filtered, recrystallized in air coolers, separated by
centrifugation, washed, dried and packaged. The mother
liquor is recycled with excess liquor wasted because of a
water imbalance. A process diagram for boric acid
manufacture and recovery of the sodium sulfate by-product is
shown in Figure 5. The overall process reaction is:
Na2B407-5H20 + H2S04
10H20 = Na2S04-10H20 + 4H3B03.
Raw Wastes
Wastes from the process consist of excess boric acid liquor,
unrecovered sodium sulfate by-product liquor, and the filter
aid and undissolved impurities from the filtration step.
These are as follows:
raw waste
material
sodium
sulfate
sodium
sulfate
sodium
borate
as (B)
arsenic
(as As)
source
Glaubers salt
recovery
Glaubers salt
recovery
BA mother 2',
liquor
kg per metric ton
cf product (Ib/ton)
average range
275 (550) not known
330 (600)
(40.5)
filter aid
and un-
dissolved
BA mother
liquor
filter
O.C36 (C.071)
(12)
62-870
(124-1740;
3.8-82
(7.7-163)
0.0018-
0.098
(0.0036-
0.197)
disposition
by-product
sale
discharged
discharced
dischargee
land filled
55
-------
1
WAS
LIGl
!
VA!
L..Q<
i
SUL
BOF
RECYCLE
.LIQUOR
^
r
»TE
JOR
RECYCLE
c-LIQUOR
r
5TE
jOR
BORIC
COOLER
!
SEPARATORS
L-CAKE
REPULPER
1
EVAPORATOR
1
CENTRIFUGE
I^S-CAKE
*
DRYER
FURIC ACID «^i
BORAX
f LIQUOR
m§TE
LIQUOR
msh ^
WATER ^
— ^VENT
WASH
WATER ^
REACTOR
1
FILTER
LcAKE
REPULPER
AND
REDISSOLVER
1
RLTER
AIR COOLER
1
CENTRIFUGE
1
DRYER
RECYCLE -^T~*-
LIQUOR
YVWSH
— ^DOWN
WASTE
\
i
WASTE
LIQUOR
^VErJT
i 1
SODIUM SULFATE TECHNICAL GRADE
BY -PRODUCT BCR1C ACID PRODUCT
FIGURE 5
ACID MANUFACTURE AT PLANT 269
56
-------
impurities
Plant Water Use
The largest volume of water use in plant 269 is for non-
contact cooling, which is 99 percent seawater. The rest of
the plant water used is high quality fresh water:
liters per metric ton of
consumption of water product (gal/ton)
process waste discharge 2,800 (673)
evaporated 2,790 (668)
boiler blowdown 3,660 (878)
noncontact cooling 109,320 (26,220)
sanitary 120 (29)
Haste Water Treatment
All of the noncontact cooling water and approximately 70
percent of the remaining municipally purchased process water
is discharged. Approximately one-half of the by-product
sodium sulfate is removed for sale.
Effluent
The effluent contains the raw wastes not sold as by-product
and not land-filled, amounting to:
kg per metric ton of product fib/ton!
vaste material average range
sodium sulfate 300 (600) 62-870 (124-1741)
sodium borate (as B) 20.2 (40.5) 3.8-82 (7.7-163)
arsenic (as As) 0.036 (0.071) 0.0018-0.098
(0.0036-0.197)
The process discharges and cooling water, which is
principally seawater, are combined and the resulting
effluent is of pH 7.8 to 8.9. Its composition compared to
the intake waters is:
Effluent (mg/ll Intake (ma/I)
average range Sea Fresh
total suspended 14.4 5.3-30.6
solids
sulfate 4,844 3138-7633
sodium 10,200
calcium 350
57
-------
arsenic 0.42 0.04-0.92
conductivity 35,000 - 32,000 1,288
(micromhos)
alkalinity (CaC03) 455 - 149
hardness 4,475 - 4,950 140-316
chloride 1,542 - 1,841 14-105
sulfite 2 - 2 -
dissolved oxygen 4.9 - 5.0 92-98
COD 49 - 50 -
800 2.3 - 1.6 0.8-1.4
phenol 0.004 - 0.004
oil and grease 1.9 - 1.0 o.l
The above effluent constituents are contributed by all the
various processes in the complex. The boric acid process
contributes no suspended solids, 90 percent of the arsenic
and 100 percent of the sulfate.
BROMINE
Bromine is produced from well brines or lake brines. The
production from lake brines by the Trona process amounts to
about 1 percent of the U.S. production. It is discussed in
the section on Trona. Data from two plants in two different
locations in the U.S. producing from well brines are given
below. The total production from these two plants amounts
to approximately seven-eighths of the U.S. production.
There are two other plants producing bromine by this
process.
Process Description
The brine stream after appropriate dilution and degassing is
extracted in a tower by debromination with chlorine and
steam. The steam and bromine stream is condensed,
separated, and distilled to obtain the bromine product. The
disposition of the spent brine depends on the individual
plant practice. The flow diagram of Figure 6 is generally
descriptive of both plants. The process chemical reaction
is:
2Br- + C12 = Br2 + 2C1-.
Raw Waste Loads
The raw wastes from the bromine extraction process include
all of the spent brines plus minor amounts of materials
added to the process stream. The amounts of the principal
raw wastes expressed in terms of the output of bromine are:
58
-------
en
WATER -1- CHLORINE
H2,S04
DHINE;
Cl ILORINE
STEAM —
I
mulling:
ABSORPTION
TOWER
NoOH UN NH3-|»
NON-CONTACT
COOLING WATER
If.
"T1**"
^
CRUDE BROMINE
SPENT BRINE
^
SEPARATOR
. BROMINE
jL^ DISTIL
DISTILLATION
BROMINE AND WATER
NBJTRAUZER
NON- CONTACT
COOLING WATER
1 T
CONDENSER
LEGEND;
•—»• WASTE BRINE TO OTHER USES OR DISPOSAL
PRODUCT
NOT PR£SENT AT
BOTH PLANTS
FIGURE 6
GENERALIZED FLOW DIAGRAM OF BROMINE MANUFACTURE
AT PLANTS 216 AND 374
-------
kg per metric ton of product (Ib/ton)
waste material plant 216 plant 374
spent brine solids 113,570 (227,140) 76,500 (153,000)
bromine (from leaks) not given nil
brine solids (from not given 0.5(1.0)
leaks and spills)
The brine solids consist principally of the chlorides of
calcium, sodium, magnesium and potassium at both plants.
The exact compositions are dependent on the composition of
the incoming brine raw material. The total amount of the
brine solids raw waste for a given plant depends principally
on the amount of bromide in the brine relative to the other
dissolved solids. The input brine at plant 216 contains
about 0.3 percent bromine,, while that at plant 374 about 0.4
percent. At both facilities the spent brine is eventually
returned to the brine fields.
Plant Water Use
Water is used in these plants for brine dilution, pump
seals, noncontact cooling and boiler feed. The consumption
of water by these uses is:
liters per metric ton of product (gal/ton)
consumption plant v216 plant 374
brine dilution 14,700 (3,530)
other process 370 (90) 9,740 (2,330)
water
boiler feed — 13,210 (3,170)
noncontact 1,770 (420) 57,030 (13,670)
cooling
The volume of water used for the various process purposes
differs widely between the two plants. However, total
process contact water is similar in both plants,
approximately 15,000 1/kkg (3,600 gal/ton) at plant 216 and
10,000 1/kkg (2,300 gal/ton) at plant 374.
Waste Water Treatment
All brine process waters at plant 216 are returned to the
brine cavity and only noncontact cooling water is dis-
charged. The waste brines are treated with lime to effect
neutralization before they are returned to their source.
At plant 374, the cooling water and boiler blowdown are
discharged without treatment. The spent brine and miscel-
60
-------
laneous process waste water (pu~.p seals, etc.) is
neutralized with ammonia and settled in ponds prior to
return to the brine cavity. Neutralization with ammonia is
unacceptable and a different neutralization agent should be
used.
Effluent
At both plants the neutralized brine and process water
wastes are returned to the brine cavity. Only cooling water
and boiler blowdown is discharged. These are noncontact
uses.
CALCIUM CARBONATE
The three plants described in this section account for over
90 percent of the U.S. production of precipitated calcium
carbonate. The mined or quarried grades of calcium
carbonate (limestone or marble dust) are not included in
this study.
Process Descriptions
At plant U77 slaked lime is reacted IT. slurry form with
carbon dioxide. The slurry is then screened and filtered.
The recovered product is dried, milled and packaged for
sale. The waste liquor from the filtration step is recycled
or discharged, depending on requirements. The coarse
materials recovered from the screening sxep are discharged.
A process flowsheet is shown in Figure 7.
The process at plant 382 is based on waste streams from the
Solvay process. A solution of sodium carbonate and sodium
bicarbonate from the soda ash plant is reacted with waste
calcium chloride liquor which has been treated through a
settler. The calcium carbonate produced together with by-
product sodium chloride and unreacted calcium chloride is
pumped to a thickener. The overflow from the thickener is
collected with plant drainage streams in a sump to which
soda ash finishing waste water is added, precipitating
calcium carbonate. This mixed stream then goes to waste
collection. The calcium carbonate underflow is filtered,
washed, atomized with steam, dried ir. a spray drier,
collected in a particle collector and pa^xa-ed for sale. A
process diagram is shown in Figure 8.
An ultrafine grade of calcium carbonate xs produced in a
similar manner to that described above with some additional
polish filtering, tunnel drying and milling.
61
-------
CARSON
WATER DIOXIDE
L i
WASH TOWER ^^
LIME
WASTE
WATER
SOLID —
WASTES
1 I
CARBONATOR
1
HOLDING TANK
1
SCREEN
FILTER
U^ SOLIDS
DRYER
1
MILLING
AND
FINISHING
1
WAS
D)SOi
PRODUCT
FIGURE 7
MANUFACTURE OF CAUCIUM CARBONATE
FROM SLAKED LIME
62
-------
NJHCO-* w
in IPMI pitrpoMOA^Ff?
:, --M I* DtUUIVlrUotn
IK-CH& !
i_:UCR j_£-Na2C03,NaHCC3
i1
*i- -IK ». DILUTION
,NaoCO, _ TANK SMALL
'^23 ^ i«rw\ AMOUNT
"oi uTiruM ^r^v;
jOLUMUN •• 1 NaOH
1 Na2C03 I
1 NaHC03 i CaCI2.
FLASH COOLER ( »| REACTOR *-^- SETTLER U
iuLTRAFINE I L- WASTE
CaCOs UNIT f f
JJggJ6 » BAROMETRIC ~mRS: TAMK WORKS WASTE
^TEAM » CONDENSER ^"^ TANK COLLECTION SUMP
• cqQ^
DBO
TO
—•» SETTLING
PONDS
11 FLOW WASHINGS f SODA ASH
IPLANT DRAINAGE ~~1 I~~ FINISHING DEPT.
WATER * fit WASTE WATER
TO SEWER PLANT WASTE
..^ TUirtfFNFn . ^ rv.«i-»i nmwtk
^ THICKtNCR j » COLLECTION SUMI
3
1 OVERFLOW' ^ILTER BACKmsn
r
c*i| TTR ^ .* • - Ftl TFR *
I/
WASH WATER
SPRAY DRYER
I
COLLECTOR
• WATER
PRODUCT
FIGURE 8
PROCESS DIAGRAM FOR CALCIUM CARBONATE
PRODUCTION AT PLANT 382
63
-------
Calcium carbonate at plant 369 is produced from four types
of raw materials generated as wastes in the Solvay process.
The first process uses a calcium hydroxide (milk of lime)
reaction with carbon dioxide in a process analogous to tnat
described earlier for plant 317:
Ca(OH)2 + C02 = CaCO3 + H2O.
The reaction mixture is filtered, while the filtrate waste
is combined with the soda ash distiller blowoff liquor. The
precipitated calcium carbonate is dried in a flash dryer and
packaged for shipment. The dusts from the drying operation
are collected in dry cyclones and mostly recycled to the
iryer. The gases from the dry cyclone are scrubbed with
water scrubbers and the effluent is recycled to the filter
wieel.
The second process recovers calcium carbonate values from
the precipitated brine muds from the brine treatment plant.
The waste stream is filtered, returning the soluble chlo-
rides to the brine plant. The solids from the filter are
sent to a storage tank where they are combined with a
solution of calcium carbonate containing some ammonium
chloride. At this point the mixture is carbonated with CO2
to precipitate any soluble calcium salts as calcium
carbonate and to dissolve any magnesium salts. The calcium
carbonate stream is then filtered, dried, screened and
stored. The fines from the screening operation are slurried
with water and recycled to the carbonating tank. The dusts
from the drying operation are collected in dry cyclones and
mostly returned to the dryer. The gases from the dry
cyclones are scrubbed and the scrubber waste is recycled to
the filter.
The third process involves the reaction of ammonium car-
bonate with calcium chloride liquor from the soda ash plant:
(NH4)2C03 + CaCl2 = CaCO3 + 2NHO.C1.
The ammonium carbonate is reacted with a calcium chloride
waste stream from the soda ash distillers, then settled and
decanted with makeup water. The decanted solution
containing ammonium chloride is returned to the soda ash
process. A portion of the calcium carbonate liquor is used
to dilute the calcium carbonate in the brine muds recovery
process. The remaining calcium carbonate liquor is filtered
and combined with the calcium carbonate from the brine muds
recovery process.
64
-------
The fourth process involves the reaction of a solution of
sodium carbonate with calcium chloride liquor from the soda
ash plant in a manner similar to that described earlier for
plant 382:
N3.2CO3 + CaCl2 = CaCO3 + 2NaCl.
The waste calcium chloride liquor from the soda ash
distillers is cooled in air-cooled heat exchangers, then
reacted with soda ash liquor from the soda ash plant. The
calcium carbonate is then filtered, washed, dried with a
flash dryer, milled and packaged for sale. The dusts from
the dryer are dry collected in cyclones and returned to the
dryer. The gases are scrubbed with water and the scrubber
effluent is recycled to the product filter.
Raw Waste Loads
Wastes at plant 477, which uses slaked lime raw material,
consist of inerts removed by the screening, and solutions
and suspensions of lime, limestone and calcium carbonate in
various waste waters:
wastes source kg per metric ton (Ib/ton)
lime inerts screening 5 (10)
carbonate inerts screening 10 (20)
lime and lime- wash tower 0.5 (1.0)
stone dust
calcium water filtrate 5 (10)
carbonate
At plants using Solvay process waste streams or process
streams as raw materials, many of the raw wastes are
attributable to the Solvay process since they are part of
the input stream. Below are listed all of the raw wastes
for plant 382 including several of those belonging to the
soda ash portion of the plant. The first four wastes listed
are due to clarification of soda ash wastes for process use
and are attributable to the Solvay operation. The last four
wastes listed are specific to the calcium carbonate
operation and would not exist in a Solvay plant unless this
product were made.
waste source kq/kkq (Ib/ton)
1. sodium distiller blowoff 908 (1,81?) ±10%
chloride liquor (DBO)
clarified through
Dorr settler
65
-------
2. calcium
chloride
DBO through
Dorr settler
2,068 (4,136) +10%
3. calcium
chloride
4. suspended
solids
5. sodium
chloride
6. suspended
solids (CaCO3)
7. calcium
carbonate
8. filter aid
and suspended
solids
overflow from
product thickeners
DBO through
Dorr settler
overflow from
product thickener
overflow from
product thickener
floor drainage
filter back wash
for wash H2O
filter
1,075 (2,150) + 10%
500 (1,000) ±10*
1,743 (3,U87) +10*
3.t (6.8) +10%
3.3 (6.5) +50%
0,3 (0.6) +10%
In the raw wastes listed above, wastes 1, 2, and 4 result
from the clarification of wastes from the soda ash plant
(CaCl2 brine) to convert them to a form usable in the
process. These wastes would be present if no calcium
carbonate plant were present.
Wastes 3 and 5 are from the product thickeners. Of these,
the calcium chloride is unreacted material from the original
soda ash waste stream. The sodium chloride is produced via
the reaction:
CaC12
Na2C03 = CaCO3
2NaCl
and represents, based on stoichiometric considerations, a 6
percent increase in dissolved solids loadings over the case
of where the CaC12_ stream from the soda ash is directly
discharged.
Thus, the raw wastes from the CaCOjJ production which add to
waste stream loadings can be retabulated as:
66
-------
waste amount
sodium 0.054 x stoichiometric quantity of CaCl2
chloride used in the reaction (this represents the
increase in dissolved solids loadings into
the waste stream)
calcium 6.7 kg/kkg from thickener overflows and floor
carbonate drainage (total) (13.3 Ib/ton)
filter aids 0.3 kg/kkg (0.6 Ib/tor.)
and
suspended
solids
The numbers presented above represent a differential raw
waste load (i.e., the wastes added to streams already con-
taining wastes from another process).
Below are listed the estimated suspended solids raw waste
loads for the entire calcium carbonate operation by all four
processes at plant 369, which is primarily a Solvay soda ash
production facility. The dissolved solids loads were esti-
mated. Some of the wastes listed are waste products from
the Solvay operation.
kg per metric ton of
calcium carbonate
waste source product (Ib/ton)
calcium lime process 2 (U)
carbonate filtrate
sodium waste brine 900 (1,800)
chloride muds filtrate
(recycled)
calcium brine muds 17 (3U)
carbonate calcium carbonate
filtrate
ammonium decant operation 1,100 (2,200)
chloride from ammonium
(recycled) carbonate process
calcium calcium carbonate 15 (30)
carbonate filtrate from
ammonium carbonate
process
67
-------
calcium calcium carbonate 1,050 (2,100)
chloride, filtrate from
sodium calcium chloride- 1,750 (3,500)
chloride, soda ash process
calcium 6 (12)
carbonate
Many of the above wastes would be present in the soda ash
complex if no calcium carbonate plant were present. The raw
wastes from the calciuir carbonate production which add to or
reduce the soda ash waste stream loads can be retabulated
as:
amount
0.054 times the stoichiometric quantity of
CaC12 used for the calcium chloride-soda ash
process represents the increase in dissolved
solids loadings into the waste stream.
NH4C1 25 kg per metric ton of calcium carbonate
(50 Ib/ton) was estimated as additional
waste due to the ammonium carbonate-
calcium chloride process
CaCO3_ 40 kg per metric ton of product calcium
carbonate (80 Ib/ton) is wasted from the
combined operation. However, the plant
recovers 425 kg/metric ton (850 Ib/ton) of
CaCO3 from the brine muds. This reduces the
net soda ash plant discharge by 385 kg/metric
ton (770 Ib/ton) of suspended solids.
The numbers presented above represent a differential raw
waste load (i.e., the wastes added to or subtracted from the
streams already containing wastes from the soda ash
process).
Plant Water Use
The principal water consumption at plant 477 is well water
averaging 15,200 liters per metric ton of calcium carbonate
product (3,640 gal/ton). A total of 76,400 1/kkg of calcium
carbonate product (18,300 gal/ton) is consumed at plant 382
and a total of 12,276 1/kkg of calcium carbonate product
(2,944 gal/ton) is consumed at plant 369. The allocation of
process-related water consumption is as follows:
liters per metric ton of product (gal/ton)
consumption plant U77 plant 382 plant 369
68
-------
evaporated 1,500 (360) 1,050 (252) 811-926
(194-222)
rrocess waste 13,350 23,350 7,880-10,1G1
discharge (3,200) (5,600) (1,890-2,44-)
contact cooling — 44,300(10,600) —
boiler feed 290 (70) not given not given
returned to N/A none 2,320 (556)
soda ash plant
The contact cooling at plant 382 is flash evaporation and
barometric condensers. Water recycling within plant 369
amounts to 3,474 1/kkg (833 gal/ton).
Haste Water Treatment
All process waste streams at plant 477 are fed into a set-
tling pond where suspended solids are removed prior to
discharge. Some polyelectrolyte is added to assist in
removal of suspended materials. The pond is used for
treatment of wastes from the entire complex.
The process waste stream at plant 369 is combined with the
distiller blowoff from the soda ash process. The combined
stream is settled in a settling pond, then resettled in a
retention basin with pH control and dilution with cooling
water.
Effluent
At plant 477 the dissolved and suspended solids loadings in
the effluent are:
TSS (mg/1) 34 (22-46)
TDS (mg/1) 450 (one sample)
pH 7.5 - 11.6
At plant 382 the waste stream after settling contains the
wastes from the entire conrplex. The discharge is quite
alkaline (pH 11-12) and high in dissolved solids. Most of
these wastes are due to the soda ash portion of the complex.
The suspended solids concentration from this pond average 25
to 30 mg/1 on a monthly average.
The effluent from the plant 369 is the combined discharge
from the soda ash plant and the calcium carbonate plant
diluted with cooling water and settled. The final effluent
69
-------
contains large amounts of dissolved solids and suspended
solids in the range of 60 mg/1.
It may be noted that there are only two plants in the U.S.
producing calcium carbonate from soda ash, and both have
been discussed here. Both of these are located in complexes
with Solvay process soda ash wastes. As could be seen from
the raw waste data, the wastes attributable only to CaCO3
production are dissolved chlorides and unrecovered CaCO3
product.
CALCIUM HYDROXIDE (HYDRATED LIME)
The plant analyzed in detail below (plant 385) has air
pollution abatement equipment installed and also has no
waterborne waste discharge. Plant 317 belonging to another
major manufacturer of hydrated lime and lime products and
located in another part of the country also has no discharge
of waterborne waste, although no internal process data. The
process described below is the general one used throughout
the U.S. industry to produce slaked lime.
Process Description
The first step in this process is the thermal decomposition
of limestone to lime in a kiln. Raw material limestone is
crushed and added to the kiln, wherein it is calcined to
effect decomposition. The resultant lime is then removed
from the kilns, and slaked by reaction with water to convert
the lime to calcium hydroxide. A process flowchart is given
in Figure 9 descriptive of the general process.
Raw Waste Load
The raw wastes produced from slaked lime manufacture at
plant 385 consist of fine dusts collected from the plant
kiln gas effluent by scrubbing systems. At this facility,
the dust removal is achieved by use of bag filters and other
dry particulate collection equipment. No wet scrubbing
techniques are employed. This raw waste dust amounts to 67
kg/kkg of product (133 Ib/ton). This amount applies also to
startup and shutdown modes of operation.
Plant Water Use
Municipal water is used without further treatment in this
plant for all plant consumptions of water. These are:
70
-------
LIMFSTONE — i 31 ,
KILN - -i - ii fi *
NATURAL GAS £fcu CO
C02, KILN GASLS VENT
INARTICULATE MATTER A
DRY BAG Mf
COLLECTORS vw
I COOLING WATER
MR - HAMMEF
OLER 1 —i MILL
' — «. HY
COOLING _jrl 1 4
WATER f
QUICKLIME
IKE -UP ^ COOLING
aER ^ TOWER
NON -CONTACT
COOLING
WATER
PROCESS
WATER
ORATOR LJ ™™%
IT l
DRY BAG
COLLEC 1 OH
HYDRATED
NU«* LIME.
PACKAGING
E
BULK
HYDRATED
LIME
STORAGE
\
SOLID
WASTES
FIGURE 9
PLOW DIAGRAM FOR CALCIUM HYDROXIDE MANUFACTURE AT PLANT 385
-------
consumption liters/kkq (gal/ton)
hydrator 555 (133)
cooling tower evaporation unknown
The cooling water flow in this plant amounts to
approximately 1,000 1/kkg (240 gal/ton), makeup to the
recycling cooling system being unknown. The only process
water is to the hydrator, which is consumed wholly in the
product; hence no waterborne process effluent.
Waste Water Treatment
There is no process contact waste water generated in this
facility.
Effluent
Because of the use of dry waste collection techniques, there
is no waterborne effluent from this plant. Plant 317 also
has no process waste water discharge.
CARBON MONOXIDE
The data analyzed in this section are from production
amounting to approximately two-thirds of the estimated U.S.
production of carbon monoxide for commercial use. The
process generates hydrogen as a by-product in an amount that
is at least three times that of the carbon monoxide on a
molar basis, and is variable due to market requirements.
For this reason, the data analysis is on a combined product
weight basis (carbon monoxide plus hydrogen) .
Process Description
Methane, air and water vapor are catalytically reacted at
elevated temperatures to form a mixture of hydrogen, carbon
monoxide, and carbon dioxide. The carbon dioxide is
scrubbed from the gas stream by the use of amines and the
hydrogen and carbon monoxide are then separated, purified
and compressed. A process diagram is given in Figure 10.
The overall process reactions at plant 220 are:
1) CH4 + H2O = CO * 3H2
2) CH«» + 2l20 - C02 + 4H2.
Reaction 1) applies when a H2 to CO product ratio of 3 to 1
is required. When the required H2 to CO product ratio is in
excess of 3 to 1, a combination of both reactions is used.
72
-------
AIR
METHANE <
REFORMER
WAFER
WATER
TREATMENT
HYDROGEN
MAKE-UP TO COMPRESSION
METHANOLAMINE AND SALE
I
METHANOLAMINE
SLUDGE
BOILER
SLOWDOWN
ION EXCHANGE REGENERANT£
HYDROGEN
CLEAN-UP
SYSTEM
LJ
CARBON MONOXIDf
TO COMPRESSION
AND SALE
CARBON
MONOXIDE
CLEAN-UP
COOLING
TOWER
COLLECTION
BOX
EEFLUENT
SEPARATED
• COMPRESSOR
WASTES
FIGURE 10
1YDROGEN AND CARBON MONOXIDE MANUFACTURE AT PLANT 220
-------
Raw Waste Load
Raw wastes from the process include ion exchange regener-
ants, boiler blowdowns, process condensates, compressor
condensates, cooling tower blowdowns, monoethanolamine
sludge, and carbon dioxide scrubber wastes. The specific
amounts and composition of each of these are estimated to
be:
kg per metric ton of combined
waste material product (Ib/tonl
carbon dioxide from scrubbers 145 (290)
monoethanolamine sludge 1 (2)
monethanolamine from condensate 1 (2)
oil from compressors 0.5 (1.0)
solids from blowdowns and 16 (32)
from regenerating ion
exchangers
Plant Water Oae and Treatment
Well water intake to plant 220 is an average of 11,700 1/kkg
ton of combined product (2,800 gal/ton) . The use is as
follows:
water consumption liters/kkg fgal/ton)
carbon dioxide scrubbers 1,130 (270)
cooling tower makeup 7,520 (1,800)
boiler feed 2,990 (717)
sanitary use 11 (3j
Waste Water Treatment
Waste water treatments include:
1. miniature activated sludge unit and chlorination
for sanitary sewerage.
2. oil separation for compressor condensate. The recov-
ered oil phase is removed from the plant by a private
contractor.
3. neutralization for ion exchange regenerant.
4. monoethanolamine sludge is removed from the plant b^
a private contractor.
5. process condensate containing monoethanolamine is
stored in underground tanks and removed from the plant
site for external treatment.
74
-------
Oil skimming of the final discharge is also practiced. The
various effluents are centrally collected and then dis-
charged. The maximum total combined discharge is 6,150
1/kkg of combined product (1,474 gal/ton).
Effluent
The average effluent composition after treatment is shown
below, it consists mostly of dissolved salts (NaCl, Na2SO4,
etc.) with only small amounts of organic materials present
and ranges in pH from 5.5 to 9.5.
con ce nt ra ti on,
mg/1
TSS 10
TDS 2,590
TVS 5
chloride
sulfate 1,400
phosphate (as P) 0.1
nitrate 0.02
sodium 280
alkalinity (as 230
CaC03)
turbidity 5
COD 40
BOD 10
calculated effluent amount,
kg per metric ton of
product (Ib/ton)
0.06 (0.12)
15.9 (31.9)
0.03 (0.06)
8.6 (17.2)
0.0006 (0.0012)
0.0001 ) (0.0002)
1.7 (3.4)
1.4 (2.8)
0.03 (0.06)
0.25 (0.49)
0.06 (0.12)
The temperature ranges given this effluent are:
summer: 37-41°c (98-105°F)
winter: 32-36°C (90-97°F)
CHROME PIGMENTS
This discussion covers the manufacture of a class of mineral
pigments based on chromate compounds. These several
materials are often made in the same facility either
simultaneously or sequentially, depending on plant practice
and the market requirements. The specific pigments covered
herein, the number of plants studied and the percent of
total U.S. production for specific pigments covered by them
*
no. of
plants
studied as
complexes
no. of
plants
studied
separately
estimated percent
of U.S. production
by the separately-
studied plants
75
-------
chrome yellow t» 3 80
and chrome
orange
molybdate 4 3 60
chrome orange
chrome green 11 26
chromic oxide 12 63
green and
Guignet's green
zinc yellow 2 2 100
The complexes and separately-studied plants represent
overall 80 percent of the U.S. non-captive production of
chrome pigments.
Chrome yellow and chrome orange are impure forms of lead
chromate. Molybdate chrome orange is a mixture of lead
chromate, lead molybdate and lead sulfate. Chrome green is
a mixture of chrome yellow (lead chromate) and iron blue
(ferric ferrocyanide). Chrome oxide green and Guignet's
green are anhydrous and hydrated forms of chromic oxide.
Zinc yellow is a complex material containing compounds of
zinc, potassium and chromium.
These individual pigments plants are parts of multi-product
inorganic and in some cases organic pigment facilities
except for one facility that produces only chromic oxides.
Because of the nearly universal characteristic that several
chrome pigments are made in a multi-plant facility, the data
analysis in this section will be carried out in two ways:
1) Four inorganic chrome pigment complexes will be analyzed
on a combined product basis.
2) Five chrome pigment types will be analyzed separately
insofar as their data can be separated within these
complexes; i.e., chrome yellow and orange, molybdate
chrome orange, zinc yellow, chrome green, and chromic
oxide green pigments.
Chrome Pigment Complexes
The four chrome pigment complexes discussed in this section
have different mixes of pigment products as follows:
76
-------
complex
pigment products
274
275
55
351
chrome yellow; molybdate chrome orange, and
zinc yellow
chrome yellow, chrome orange, and molybdate
chrome orange
chrome yellow, molybdate chrome orange, and
zinc yellow
chrome yellow, chrome orange, molybdate
chrome orange, chrome green, chromic oxide
and hydrated chromic oxide
A generalized flow diagram for chrome pigment complexes is
given in Figure 11, which is applicable to any one given
complex only in the broadest sense.
The interrelationships of pigment processes at pigment
complexes can be seen in the example plant complex shown in
Figures 12 and 13. This complex also manufactures iron
blues, which is an ingredient in chrome green as is shown in
Figure 13. The data from this complex are not analyzed in
this section.
Chrome Pigment Complex Raw Waste Loads
The process raw wastes from each of the four complexes are:
waste mate-
rial at
complex no.
sodium
acetate
sodium
chloride
sodium
nitrate
sodium
sulfate
potassium
chloride
kg per metric ton of combined product (Ib/ton)
326
65.5
(131)
198
(296)
96
(192)
120
(240)
4.1
(8.1)
present
present
hydrochloric 0
255
475
(950)
411
(823)
72.5
(145)
10.8
(21.6)
30.9
351
158
(316)
3
(6)
265
(530)
118.5
(237)
0
77
-------
WATER
1
RAW MATERIALS*
oo
WASH
WATER
VENT
WASTE WATER
(BY-PRODUCT SALTS,
UNREACTEO MATERIALS, ETC.)
NON-CONTACT
STEAM
WASH-DOWN
WATER
REACTOR
FILTER
DRYER
GRINDING
AND
SCREENING
MEf>
PIGMENT
PARTICIPATE
WASTES
PIGMENT
PRODUCTS TO
PACKAGING
FIGURE 11
GENERALIZED FLOW DIAGRAM OF CHROME PIGMENT COMPLEXES
-------
STEAM
¥
PIO 1 FAD «MmnniQ» u
DISSOLVE
ACETIC ACID §»»
NITRIC ACID ——••••«•». 1
>"— 1
SODIUM BICHROMATE— 0»J
STEAM WATER
1 WATER WA|ER ^ F|LTER
AND » AND
TRFAT 1 1 U/AQU .
^ TREAT | | WASH ^ r^AST
L
DRY —
STEAM — fri
•••
^WASTES
fwiVSTES
STEAM WATER 1
I TR I 1
"* STRIKE
AND — *i \W\SH — -*• FILTER — -^
mm TRFAT
^^*
^1
"*** k TO WASTE
_^ /TREATMENT
J
GRIND,
Rl FWn CHROME
PACK PRODUCT
1» \ TO WASTE
/TREATMENT
^WASTES **/
1
i
GRIND,
~~~ BLEND MOLYBDATE
PACK PRODUCT
FIGURE 12
CHROME YELLOW AND MOLYBDATE ORANGE MANUFACTURE AT COMPLEX 332
-------
COPPERAS
SULfURIO ACID
SODIUM FERROCYANIDE
AMMONIUM SULFATE
IRON BLUE
PRODUCT
LITHARGE
NITRIC ACID
OTHER
SODIUM
BICHROMATE
GRIND,
BLEND
AND
PACK
xTO WASTE
/TREATMENT
CHROME
YELLOW
AND/OR
CHROME
GREEN
PRODUCT
FIGURE 13
IRON BLUE, CHROME YELLOW AND CHROME GREEN MANUFACTURE
AT COMPLEX 332
-------
acid
(61.8)
soluble
chromiur.i
not
a i V'"> n
8.5
(17)
7.2
(14.4)
{ .3 or)
soluble
•zinc salts
(as Zn)
borates
silica
pi-iment
partic-
ula res
16
(32)
chrome
oxide and
hydroxide
lead
residues
(as Pb)
0.08
(0.15)
0.05
(0.10)
not
given
present
(12)
present 0.31
(0.62)
present 21.7
(43.4)
0.03
(0.06)
1.3
(2.6)
3.2
(6.4)
0.21
(0,42)
not
qiven
The borates (sodium borate and boric acid) in raw wastes are
associated only with a rrocess for hydrated chromic oxide
^ig. ent and v/Duld not appear unless this product were made.
Similarly, zinc salts in the raw waste are associated with
the production of zinc yeixow. Sodium acetate is rot
universally a raw waste in these complexes because lead
acetate or acetic acid are used as raw materials only by
some manufacturers. One- of the chief troublesome raw wastes
is the "pigment .;.arti culat es" wr.ich are slightly soluble
compounds of chromium, lead, zinc, molybdenum, etc.
Chi22!?- P-iqgient Goggle x Water Use
The pi^cess-related consumption of water for the four
compl "• .:es and the calculated average values on the basis of
their annual average productions and hydraulic loads are:
water con-
sumption at
compley no.
liters per metric ton of combined product (gal/ton)
326 275 255 351 average
81
-------
process
waste
contact
cooling
non-
contact
coolina
33,200
(7,960)
U,910
(1,180)
est.6t»,850 66,030 102,070 66,520
(15,540) (15,800) (2«*,460) (15, 940)
0
very
little
0
7,340
(1,760)
0
1,024
(245)
0
4,430
(1,060)
evaporated
and/or
consumed
in product
boiler feed
total
consumption
2,950
(706)
6,550
(1,570)
47,610
(11,410)
unknown
not
given
80,580
(19,310)
9,170
(2,700)
5,500
(1,320)
88,240
(21,140)
3,800
(910)
not
given
106,890
(25,620)
5,310
(1,270)
6,025
(1,440)
80,830
(19,370)
Quantitative data was not available for complex 275, except
for total consumption. The estimated value of process waste
hydraulic load is based on the total less the average values
for the other types of consumption. Process waste discharge
water seems highly variable and the average value calculated
above is close to the values for complexes 275 and 255. The
total consumption values for these two complexes are also
close to the average.
Waste Water Treatment at Chrgme Pigment Complexes
At complex 326 the treatments for the pigments are separable
to the extent that they can be discussed on an individual
picrment basis. This information is presented in subsequent
sections dealing with the individual pigments.
At complex 275 the chrome pigment wastes are treated by a
settling basin prior to discharge. The settled solids
consist of lead chromates.
At complex 255 all plant effluents are collected and
processed through a chemical treatment step. The stream is
then filtered. At times the filters are unable, because of
the nature of the feed (metal hydroxides) and mechanical
problems, to handle the entire plant flow. Consequently,
some portion of the total flow is bypassed around the filter
area to the effluent line joining the flow from the filters.
This condition is exaggerated during periods of zinc
chromate manufacture when, because of the nature of the raw
82
-------
waste load (large volumes of metal hydroxides), less of
total flow to the filter area can be handled.
the
303 the chrome pigment wastes combined with
an associated iron blue pigment plant are
At complex
wastes from
treated by equalization, neutralization with lime, and
clarification prior to discharge. This treatment does not
remove sodium nitrate, sodium acetate, sodium sulfate,
sodium borate, or ammonium sulfate. However, lead,
chromium, iron and cyanide are reduced by 90 to 95 percent.
?ffluents From Chrome Pigment Complexes
The effluents froir complex 274 are discussed separately for
each specific pigment in later sections.
Th° effluent stream from complex 275 is discharged at pH in
the range of 5.5 to 8.5. No further data were obtained
since the treatment at this facility is rudimentary,
consisting essentially of the settling of solids. The
effluent consists of all the soluble raw wastes plus some
fraction of the insolubles. The solubles are sodium
sulfate, zinc sulfate, and sodium nitrate. The insolubles
are lead chroirate and lead molybdate,
The effluent data available from complex 255 are the
treatment discharge stream after it has been mixed with a
larger discharge stream from a different plant process,
which has principally organic materials as wastes. The
composition of this effluent stream and the amounts of
wastes where attributable in part to the chrome pigments
complex are:
kg per metric ton of chrome pigments
(Ib/ton)
TSS
TDS
BOD
COD
chlorides
copper
chromates
(as Cr)
388 (142-700)
9800 (7000-12000)
105
166
1500 (700-2000)
9.4 (0.05-42)
6.5 (1.0-257)
30
760
(60)
(1520)
116
0.73
0.5
(232)
(1.5)
(1.0)
83
-------
manganese
arsenic
mercury
(umg/1)
lead
zinc
3.5 (0.01-25)
0.05 (0.01-3.5)
0.6 (0.01-3.0)
4.4 (0.2-32)
0.2 (0.01-1.5)
0.27
0.004
0.34
0.015
(0.54)
(0.008)
(0.68)
(0.03)
The temperature of this effluent averages 38°C (100°F) with
a range of 21-49°C (70-120°F). The pH of this effluent
averages 7.6 with a range of 7.3 to 8.2 The lead content of
the above stream is nearly the same as that given in the raw
waste. The zinc and chromium contents, however, are
markedly reduced over the raw wastes; over 99 percent
reduced for the zinc and 94 percent reduced for chromate.
The effluent of complex 351 includes the treated effluent
from an iron blue pigment plant. The average composition of
the present total effluent after tretment is given below
from COE permit application data. Also given are the
calculated values of quantity of several wastes attributable
to the chrome pigments, based on the average chrome pigment
production.
TDS
TSS
ammonia
nitrate
phosphates (as P)
turbidity
total hardness
sulfate
chloride
cyanide
concentration.
(mg/11
6000
30
100
200
0.1
20
1000
1000
300
0.2
kg per metric ton of
chrome pigments (lb/tgn)^
1,805 (3,610)
8 (16)
53
(106)
265
265
80
(530)
(530)
(160)
84
-------
boron 2 0.5 (1)
total chromium <4 1 (2)
copper 0.5
iron U
lead 2 0.5 (1)
zinc 0.2 0.05 (0.1)
BOD 400
COD 500
The TDS quantity is higher than expected from the raw waste
load, presumably because of the other process effluent com-
bined with it. The boron quantity is similar to that in the
raw waste load of borates. The apparent reduction in
chromium over the raw wastes is about 86 percent. The
presence of zinc in this effluent cannot be accounted for,
since no zinc yellow is made in this complex, no zinc raw
materials are used in the other pigments including iron
blue, and no zinc raw waste values were given. The pH of
this effluent ranges from 6 to 8.
Chrome Yellow and Chrome Orange Plants
Chrome orange is made with chrome yellow, when it is made.
At the facilities studied, only one manufactures chrome
orange (plant 351). The data below are combined for these
two pigments at that facility.
Chrome Yellow and Chrome Orange Process Descriptions
At plant 326 lead oxide is dissolved in nitric or acetic
acid. This solution is reacted with sodium dichromate
solution and the resulting suspension is fed to a
development tank to allow the reaction to proceed to
completion. The product is then recovered from the solution
by filtration and is washed, dried, milled and packaged. A
process flowsheet is given in Figure 14.
At plant 351 chrome orange is made by the chrome yellow
process by adjusting the pH of the dichromate solution. The
process is similar to the above except that lead nitrate is
also involved. At plant 255 the lead is made soluble by
in nitric acid solely.
85
-------
LEAD OXIDE
WATER
NITRIC OR
ACETIC ACID"
DISSOLVING
TANK
DISSOLVING
TANK
1=
SODIUM
BICHROMATE
WKTER
MIX TANK
I
DEVELOPMENT
TANK
SOLIDS
TO
LANDFILL
WASTE
TREATMENT
, L
SOUDS
REMOVAL
i •
EFFLUENT
FILTRATION
AND
WASHING
I
DRYER
1
MILLING
AND
PACAGING
PRODUCT
FIGURE 14
CHROME YELLOW MANUFACTURE At PLANT 326
86
-------
Chrome Yellow and Chrome Orange
The raw waste values for three separable plants are:
waste material
at
plant no.
sodium acetate
sodium chloride
sodium nitrate
sodium sulfate
soluble chromium
salts (as Cr)
lead salts (as Pb)
pigment
participates
Chrome Yellow and
kq/metric ton of chrome yellow & oranqe
326
137 (273)
12 (23)
247 (495)
not
given
Chrome Oranqe
(lb/tonl
351
250 (500)
250 (500)
5.7 (11.3)
2.1 (U.2)
not
given
Plant Water Use
255
625
150
7
25
(1,250)
(300)
(14)
(50)
The hydraulic loads for the three separable plants are:
water consumption liters/metric ten of chrome yellow & prang
at (gal/ton)
plant no. 326 351 2.55
process waste
noncontact
cooling
consumed in
product or
evaporated
boiler feed
43,900
(10,500)
6,600
(1,600)
1,760
(420)
11,000
(2,600)
121,900
(29,200)
3,340
(800)
not given
35,000
(8,300)
3,090
(740)
1,000
(240)
not given
Chrome Yellow Plant Waste Water Treatment
Treatment of the waste streams at plant 326 includes
chemical treatment and settling prior to discharge.
Specifically, all process waste streams are first treated
with either sodium sulfite, sodium bisulfite or sodium
hydrosulfite in an acidic medium to reduce chromates present
to trivalent chromium. This waste stream is then further
treated with lime to remove the acidity and precipitate
chromium and lead salts. The insolubles formed are then
s:
-------
removed in a settling lagoon prior to discharge. The solids
recovered from the lagoon are landfilled on the plant site.
The wastes from plants 351 and 255 are treated combined with
the wastes from other pigment processes in their respective
pigment plant complexes, discussed earlier.
Chionie_Yellow_Plant_ Effluent
The effluent composition estimated as contributed to the
overall plant effluent from plant 326 as given in tne COE
permit application together with calculated average amounts
of wastes are:
concentration.
Iffla/lL kg per metric ton of chrome
average range yellow (Ib/ton)
12
280
300
240
160
3
3
70
0.1
10
0-50
100-7,770
100-3,300
0-3,100
0-3,000
0-100
0-100
1.6
37
40
32
21
0.4
0.4
9.3
0.01
1.3
(3.2)
(74)
(80)
(64)
(«)
(0.8)
(0.8)
(19)
(0.02)
(2.6)
chloride
sulfate
sodium
calcium
acetate
chromate*
lead*
alkalinity (total) 70
phosphates
COD
*present as suspended materials.
The pH of the effluent ranges from 5.5 to 8.0. The sulfate
content of the raw waste was obviously lowered by the lime
treatment.
Molybdate Chrome Oranqe_Plants
Data from three separable plants are given below. One plant
operates both batch and continuous operations for this
pigment.
88
-------
Chrome Orange Process Descriptions
At plant 326 molybdic oxide is dissolved in aqueous sodium
hydroxide and sodium chromate is added to the resulting
solution. This solution is mixed and reacted with a
solution of leai oxide in nitric acid. The reacting
solution is tnen fed to a holding tank, wherein the reaction
goes to completion. The resulting suspension is filtered
and the recovered product is washed, dried, milled and
packaged. A. process diagram is given in Figure 15. Plants
255 and 351 are the same in all essential details.
Molybdate Chrome Orange Raw Waste Loads
The data from three seoarable clants are as follows:
waste material
at plant no.
sodium chloride
sodium nitrate
sodium sulfate
soluble chromium
salts (as Cr)
chromium hydroxide
lead salts (as Pb) 5 (10)
silica
key/metric ton of molybdate orange (lb/ton)
255 (batch) 2_55_lcont}_ 326
351
200
(400)
650
(1,300)
125
(250)
1
(2)
125
(250)
550
(1,100)
50
(100)
8
(16)
23
(46)
568
(1,135)
76
(151)
17.5
(35)
500
(1,000)
5 (10)
3.4 (6.8)
1.25 (2.
pigment
particulates
20 (40)
20 (40)
not
given
not
given
The chief difference between batch and continuous processes
is in the greater amount of by-product salts in the raw
waste of the former.
Molybdate Chrome Orange Plant Water Use
The hydraulic loads given for these three plants are:
water consumption
at
liters/metric ton of molybdate orange
jqai/ton)
89
-------
WOLYBD:C OXIDE«
CAUSTIC SODA-
WATER
DISSOLVER
soniuu ^
W/VTFR ^
MIX TANK
DISSOLVER
LEAD OXIDE
NITRIC ACID
MIXER
CHEMICAL
TREATMENT
i
SLUDGE
SEPARATION
1
HOLDING TANK
1
FILTRATION
AND
WASHING
1
DRYER
I
EFFLUENT
SOLiOS
TO
LANDFILL
MILLING
AND
PACKAGING
PRODUCT
FIGURE is
MOLYBDATE ORANGE MANUFACTURE AT PLANT
90
-------
plant no.
orocess waste
noncontact
cooling
consumed in
product, or
evaporate?.
boiler feed
255 (batchl 255 (contl 326
25,000
(6,000)
8,340
(2,000)
2,080
(500)
37,400
(8,960)
1,740
(417)
434
(104)
40,351
(9,670)
0
not given not given
P,350
(2,000)
3,500
(830)
109,000
(26,100
0
3,500
(840)
not give
At plant 326 ice is used in the process as part of the
reactor water, diminishing the cooling requirement.
Molybdate Chrome Orange Plant Waste Water Treatment
Treatment at plants 255 and 351 are
combined pigment complex treatments.
described earlier in
The waste waters at plant 326 are collected and acidified
and their hexavalent chromium content is then reacted with
sulfites or hydrosulfites to reduce to trivalent chromium.
Also, sodium sulfate is added to precipitate lead as the
sulfate. The effluent is further treated with lime to
precipitate chromium hydroxide and residual lead salts and
is fed to a settling lagoon where the solids settle out.
The solids are recovered and landfilled and the treated
effluent is then discharged. Future plans include the
installation of filters and clarifiers at the end of the
treatment system to further reduce concentrations of
suspended materials.
Molybdate Chrome Orange Plant Effluent
The estimated (by manufacturer) contribution of the plant
439 effluent to the complex discharge is given below
together with the calculated average quantities of each
waste material.
concentration.
(mcr/1^ kg/metric ton of molybdate
average range orange (Ib/ton)
chloride
sulfate
25
95
0-100
10-7,000
5
19
(10)
(38)
91
-------
sodium
calcium
chromate*
lead*
300
240
3
3.5
10-3,300
0-3,100
—— _
60 (120)
50 (100)
0.6 (1.2)
0.7 (1.4)
alkalinity (total) 0.70 0.14 (0.28)
phosphates 0.1 0.02 (0.04)
COD 10 2 (4)
TOC 10 2 (4)
*present mostly as suspended insolubles.
The above represents an apparent reduction over the raw
waste load of 80 percent for lead and roughly 90 percent for
chromate.
Zinc Yellow Plants
Two separable plants are analyzed below.
Zinc Yellow Process Descriptions
Zinc oxide, hydrochloric acid, sodium dichromate and
potassium chloride are reacted to give a zinc yellow slurry.
This slurry is then filtered, washed, dried, milled and
packaged for sale. The filtrate is treated in ion exchange
columns to recover chromates which are recycled back to the
reactor and the filtrate is then treated with soda ash and
filtered to recover zinc carbonate as a coproduct. The
filtrate from this step is then discharged. This material
is then dried and packaged. A process diagram is given in
Figure 16 for plant 326.
Zinc Yellow Raw Waste Loads
The data from the two separable plants are:
waste material kg per metric ton of zinc yellow fib/ton^
at plant no. 255 326
hydrochloric acid 100 (200)
sodium chloride 300 (600) 281 (562)
92
-------
"'IMP (Y'inr ^
HYDROCHLORIC ACID ^
SODIUM DICHRCMATE **
pfiTft^^iiiM rni nrrinr ^>
COLOR
MAKING
TANK
^
r
FILTER
DRYING
MILLING
PACKAGING
vo
CO
t
WASH
WATER
~ FILTRATE
HOLDING
TANK
CHROMATE
RECYCLE
ION
EXCHANGERS
I
ZINC
REMOVAL
FILTER
HYDROCHLORIC ACID TO ADJUST pH
REGENERATION CHEMICALS
SODA ASH
EFFLUENT
ZINC CARBONATE CO-PRODUCT
FIGURE 16
ZINC YELLOW MANUFACTURING FLOW DIAGRAM AT PLANT
-------
potassium chloride 35 (70) 8 (16)
soluble chromium 12 (24) 18 (36)
salts (as Cr)
soluble zinc salts 19.5(39) 32 (63)
(as Zn)
pigment particulates 20 (10) not given
Zinc Yellow Plant Water Use
The hydraulic loads are:
water consumption liters/metric ton of zinc yellow (gal/tony
at plant no. 255 326
process waste 20,000 (4,800) 18,800 (4,500)
noncontact cooling 0 6,300 (1,500)
consumed in product 1,000 (240) 800 (200)
or evaporated
boiler feed not given «T200 (1,000)
Zinc Yellow Plant Waste Water Treatment
Treatment at plant 255 is discussed earlier in pigment
complex treatments. At plant 326 treatment consists of two
ion exchange columns used to recover chromate values. The
ion exchange regenerants are returned to the process.
Further treatment involves addition of soda ash to the
effluent from the ion exchange system. This effects
precipitation of zinc salts as the carbonate, which is then
recovered as a coproduct for sale. The effluent after zinc
salt recovery is then discharged.
Zinc Yellow Plant Effluent
The effluent composition from plant 326 is shown below
together with the calculated average quantities of wastes
discharged.
concentration.
(mg/1) kg/metric ton of product
average range (Ib/ton)
TDS 28,000 526 (1,053)
94
-------
chloride 11,000 207
sodium 17,000 320 (640)
chromate l.C 0-3.0 0.02 (0.04)
zinc 1.0 0-5.0 0.02 (0.04)
COD 20 -—
BOD 20 —
The pH of the effluent averages 6.8. The treatment
apparently results in removal of most of the chromium and
zinc present in the raw waste. The discharged material is
essentially a sodium chloride brine solution. The amounts
of effluent as dissolved solids, as calculated from reported
data, are higher than the raw waste total of 289 kg/kkg (576
Ib/ton) of potassium and T:.aium chlorides by, presumably,
the addition of solubles released from the ion exchange
reaction raising tne soluble waste quantitv to 526 ka/kka
(1,053 Ib/ton). ' y
Chrome Green__Plants
Only one separable chrome green plant was available for
analysis.
Chrome Green Process Description
Chrome green is produced by mixing slurries of chrome yellow
and iron blue picjrr.cnts. Tiie presence of an iron blue
pigment plant >n-site has been found in all instances of
chrome green manufacture. The manufacture of iron bi^e is
analy2ei in a later section. The slurry mixtures a<->
filtered e collier Fiquve i.~. for. a fiov, c'i.-- im
within a complex. At plant 313 the chrome yellow pigment
used is simply lead chromace made from the lead nitrate
starting material.
Chrome Green Raw_wa_ste_Loa_ds
The raw waste data from plant 351 are:
waste material kg/metric ton of_cjhrcjne_gxeen_.llb/tonV
sodium nitrate 400 (800)
95
-------
pigment particulates not given
Chrome Green Plant Water Use
The hydraulic loads at plant 351 are:
water consumption liters/metric ton of chrome green(gal/ton)
process waste
non contact cooling
consumed in process
48,400
0
1,540 -
(11,600)
(370)
or evaporated
boiler feed not given
Chrome Green Plant Waste Water Treatment
and Effluent
No separate waste water treatment or effluent data were
available. All treatment data for this pigment are given
earlier in combined form with the pigment complexes.
Chromic Oxide Pigments
The two chromic oxide green pigments, anhydrous chromic
oxide and hydrated chromic oxide (Guignet's green) are made
at two plants analyzed below. At both, the production of
the anhydrous is approximately ten times the production of
the hydrated chromic oxide.
Chromic Oxide Process Description
1) Anhydrous Chromic Oxide at Plant 351
Sodium dichromate, sulfur and wheat flour are mixed with
water in a blender and the resultant slurry is heated in a
kiln to react. The material recovered from the kiln is then
slurred with water, filtered, washed, dried, ground to size,
screened and packaged. A process diagram is given in Figure
17. The overall process reactions are:
Na2Cr207 + S = Cr2O3 + Na2SO4
Na2Cr2O7 + 1/3C6H10O5 = Cr2O3 + CO2 + CO + 2NaOH + 2/3H2O
Hydrated Chromic Oxide (Guiqnet's Greeni at Plant 351
96
-------
SODIUM
DICHROMATE «
WATER
SULFUR
WHEAT FLOUR-
NON-CONTACT
COOLING WATER
WATER -
WATER-
NON-CONTACT
STEAM
BLENDER
I
KILN
1
SLURRY
TANK
I
FILTER
I
DRYER
I
GRIND,
SCREEN,
PACKAGE
I
PRODUCT
C02,CO VENT
WASH WATER
•VENT
FIGURE i?
ANHYDROUS CHROMIC OXIDE PIGMENT
MANUFACTURE AT PLANT 351
-------
Sodium dichromate solution and boric acid are mixed in a
blender and heated in an oven. The reacted material is
slurried with water and washed. Most of the washwater from
the process is treated with sulfuric acid to recover boric
acid. A waste stream containing boric acid and sodium
sulfate leaves the boric acid recovery unit. The overall
process reactions are:
Na2Cr207 + 4H3BO3 = Cr2O3.2H2O * 3/2G2 + Na2B4O7 + UH2O
Na2B407 + H2SO4 + 5H2O = 4H3BO3 + Na2SOf».
The product with some of the final wash water is filtered,
rewashed, dried, ground, screened and packaged. A process
diagram is given in Figure 18.
Plant 349 differs from the above in that sulfur solely is
used as a reducing agent.
2) Process Description at Plaiv^3a9
Sodium chromate, sodium dichromate, caustic soda and sulfur
are blended with water in a mixer and the resultant slurry
is calcined to react. The material recovered from the kiln
is then slurried with water, leached with sulfuric acid,
filtered, washed, dried, ground to size and packaged. A
process flow diagram is given in Figure 19. The overall
process reaction is:
Na2CrOU + 2Na2Cr207 + 6S = 2Cr203 + 2Na2S2O3
The sodium thiosulfate is oxidized to sodium sulfate with
either oxygen in the kiln or with1 an excess of sodium
dichromate and caustic.
Chromic Oxide Raw Waste Loads
The raw waste load data combined for both anhydrous and
nydrated chromic oxide are:
waste material kg/metric ton of ^both_ghrgm-i ^ oxides Ub/ton»
at plant no. 349 §5^ * L
sodium sulfate 1,750 (3,500) 811 (1,622)
sodium borate and gg (160)
boric acid
soluble chromium 3 (6)
salts (as Cr+6)
98
-------
SODIUM ^
DiCHROMATE^^^
BORIC ACID »
WATER ^
BLENDER
1
OVEN
1SULFURK
ACIC
SLURRY
TANK
1
WASH
1
FILTER
1
DRYER
1
GRIND.
SCREEN^
PACKAGE
c— BORIC ACID
J> RECYCLE
^ DUSTS.
^ OXYGEN
BORIC ACID
• to nrrrftfTRY ^VKASTE
) HL.UUVIJTT ^uteTFe
UNIT WATER
I
fc» VENT
PRODUCT
FIGURE is
HYDRATED CHROMIC OXIDE PIGMENT
MANUFACTURE AT PLANT 35!
QG
-------
SODIUM CHROMATE/
SULFUR
WATER
RECYCLE TREATMENT
FILTER CAKE
SULFUWC ACID
WASH YWTER -
REDUCTION
CALCINATION
I
WASHING
(LEACHING)
1
FILTRATION
1
DRYING
MILLING
AND
PACKAGING
I
PRODUCTS
WASTE WATER
TO TREATMENT
FILTRATE TO
TREATMENT
VENT
FIGURE 19
CHROMIC OXIDE MANUFACTURE AT PLANT 349
IOC
-------
pigment participates 2.8 (5.6) 0.73 (1.5)
(as chromic oxide)
reaction gases 77 (154)
(CO2, CO, 02)
The use of only sulfur as a reducing agent in plant 349 both
increases the sulfate raw waste and eliminates the CO2, CO
and O2 byproducts and the borate raw wastes present at the
other plant.
Chromic Oxide Plant Water Use
The water use data combined for both products are given
below:
water consumption liters/metric ton of both chromic oxides
at tqal/topl
Plant no. 349 351
process waste 27,820 (6,670) 31,020 (7,430)
noncontact 318 (83) 4,660 (1,120)
cooling
consumed in product 4,170 (1,000) 2,030 (490)
or evaporated
boiler feed 1,740 (417) not given
The process wast : discharge hydraulic load in both cases is
quite similar.
Chrogig-Oxide_Plant_Waste Water Treatment
The present treatment system at plant 349 consists of a
sulfur dioxide scrubber process for reduction of hexavalent
chromium to trivalent chromium, precipitation with caustic
soda to produce chromic oxide, and filtration with the
filter cake returned to the process. The effluent from the
chromium treatment system is then fed to a thickener and
finally combined with other plant water streams containing
filter wash water, miscellaneous process and washdown water,
and cooling water. These effluents are currently disposed
or in percolation ponds.
In the near future, the plant plans to improve the chemical
system for reduction of hexavalent chromium with
precipitation and solid recovery. The percolation ponds
101
-------
will be replaced with impervious lined ponds for treatment
and settling with effluent discharged to the river. The
soluble salts will not be removed by this treatment.
The treatment at plant 351 is integrated with a pigment com-
plex and consists of equalization, neutralization with lime,
and clarification. This treatment is reported to be 90-95
percent effective in removing lead, chromium, iron and
cyanides. Soluble salts are not removed.
Chromic Oxide Plant Effluent
At the present time, plant 349 has no discharge to a
waterway but disposes of the waterborne wastes in seepage
ponds. This disposal method is scheduled to be replaced in
the near future with extensive treatment and an effluent
discharge to the river.
At plant 351, the only effluent waste material that can be
unequivocally attributed to chromic oxide manufacture from
the complex effluent is its boron content, which amounts to
4.0 kg per metric ton of both chromic oxide products (7.9
Ib/tcn). This is approximately one-third the boron content
of the raw wastes and is present in the form of soluble
borates.
CHROMIC ACID
The data analyzed in this section are from production
amounting to approximately 40 percent of the U.S. production
of chromic acid. There are four chromic acid plants in the
U.S., two of which are attached to sodium dichrornate
operations.
Process Description
Sodium dichrornate liquor from the dichrornate manufacturing
operation is reacted with sulfuric acid, the solution is
filtered to recover impure chromic acid, and the mother
liquor, containing sulfuric acid and sodium sulfate, is
returned to the dichromate operation for reuse. The recov-
ered chromic acid is fed to a melter in which the sodium
bisulfate liquifies and is separated from the chromic acid.
The bisulfate is returned to the dichromate operation and
the chromic acid is resolidified, flaked and packaged for
sale. Plant 336 produces chromic acid from approximately 30
percent of its dichromate production. The reuse of sulfate/
sulfuric acid streams appears to be the rule rather than the
exception. A process flow diagram is given in Figure 20.
102
-------
SULFURIC ACID«
SODIUM
DICHROMATE
LIQUOR
CHROMIC
ACID
REACTOR
FILTER
MELTER
FLAKER
• PRODUCT
o
CO
SULFURIC ACID
LIQUOR TO
DICHROMATE
PLANT
LIQUID SODIUM
BISULFATE TO
DICHROMATE
PLANT
FIGURE 20
CHROMIC ACID MANUFACTURE
-------
Raw Waste Load
The only wastes not recycled to ana used by the dichrornate
portions of the plants are spills, washdowns and cooling
tower and boiler blowdowns associated with the chromic acid
portion of the plant. The amounts of these are unknown, but
are relatively small and are already included in the whole
waste of the sodium dichromate facility as analyzed in an
earlier program. Further attribution of wastes to chromic
acid production would be redundant and misleading, since
they are covered by the dichromate production in instances
where chromic acid is produced in a dichromate operation.
Plant Water Use
In this facility the only process water used is in the
dichromate portion of the operation, which can be considered
a preliminary step in the chromic acid process. The amount
of cooling water, boiler feed, waste treatment water (if
any), and sanitary water have been already covered in the
sodium dichromate process analysis. The water used in
boiler feed is softened and the well water is filtered,
softened and chlorinated before use at plant 336.
Waste Water Treatment
The treatment of waste water is associated with sodium
dichromate production and consists of adding pickle liquor
to effect reduction of chromates present and then lagooning
all effluent waters to settle out suspended solids. This
treatment removes 99 percent of the hexavalent chromium and
the discharae contains less than 0.01 mg/1. When full, the
lagoon discharges to a nearby river.
Chromate waste control in this plant is excellent. All
rainwater, washdowns, spills and minor leaks in the part of
the plant which handles hexavalent chromium are captured in
the area's sumps and used in the process. Storage
facilities are provided to contain a heavy rain and return
the water either to the process or to treatment. Separate
rainwater drainage is provided for areas not handling
hexavalent chromium. Sewers are continuously monitored".
Even cooling tower and boiler blowdowns ao through the
process waste treatment, as do all waste sludges. A batch
system is used in the treatment process. Each batch is
treated and analyzed before release to the lagoon.
Effluent
104
-------
This is essentially a zero discharge system insofar as
chromic acid production from sodium dichromate liquor is
concerned. The effluent at plants of this sort is due
essentially to the dichromate production and has been so
attributed in the earlier study.
COP PERSULFATE
There are four known significant plants producing cooper
sulfate. The two analyzed in this section account'for
approximately 70 percent of the total U.S. production. They
are located in different regions of the U.S. The chief
process difference between the two that impacts on the waste
load is the use of pure copper raw material at one and an
impure copper source at the other.
Process Description
At plant 302, copper, 93 percent sulfuric acid, water and
air are introduced into a steam heated oxidizing tower. The
reaction product, copper sulfate solution, is sent first to
a settling tank and then to an atmospheric crystallizing
tank. The weak liquor from the crystallizing tank is
recycled. The concentrated crystals from the atmospheric
crystallizer are fed to a centrifuge, where the product is
separated and dried for sale. The liquor from the
centrifuge is recycled. The weak liquor in the vacuum
crystallizer is concentrated to a slurry, which is then
further concentrated. The product is separated by
centrifugation, dried and packaged for sale. All mother
liquors from this step are also recycled. A process diagram
is given in Figure 21.
The process reaction is:
Cu + 1/2 02 + H2S04 + UH20 = CuSO4.5H2O.
The process used at plant 299 is a combination of a by-
product recovery from an adjacent copper refinery and a
waste abatement procedure. A waste stream from the refinery
containing 35 percent copper, 18 percent sulfuric acid and
about 0.2 percent nickel is fed to an oxidizer tank where it
is reacted with copper shot, live steam and air. The
resultant solution is sent to noncontact steam heated
evaporators for concentration and then through filters where
slimes are collected and sent out for precious metals
recovery. The filtrate goes to a series of crystallizers
which utilize once-through noncontact cooling water. The
crystals of copper sulfate are separated by centrifugation,
screened, dried and packaged. Part of the centrifugate and
105
-------
1 -----—--—-—-— -—-—-^
TO OTHER
PROCESS
f
SULRJRIC ACID -^
ANDVftTER •*• SETTLING
COPPER SHOT— -fr REACTOR — •> TANK "^
COMPRESSED AIR-H^
SLUDGE
•
WATER *»
IH STEAM pi
r
F
COPPER SULFATE M)
CRYSTALLIZING
TANK
I
MOTHER
1 IQLJOR
TANK
1
VACUUM
CRYSTALLIZER
1
VACUUM
SYSTEM
_^ CENTRIFUGE — » DRYER pi PRODUCT
^WATER
1GURE 21
UIUFACTURE AT PLANT 302
-------
wash waters are recycled to the oxidizer tank and
evaporators and part is wasted to prevent a buildup of
nickel impurities. This waste stream is used to make
another product. A process diagram is given in Figure 22.
Raw Waste Loads
Raw wastes from the process at plant 302 include 35 to 45
kg/kkg (70 to 90 Ib/ton) of copper sulfide as sludges from
filtration of the oxidation tower material and an un-
specified amount of copper sulfate lost by spills and
washdowns. These copper sulfate wastes are totally
recycled.
The process raw wastes at plant 299 consist of spent mother
liquor used to make another product, slimes sent to another
facility to recover precious metal values, and washdown
waters are treated prior to discharge:
source
mother
liquor
oxidizer
slimes
floor
wa shdown
water materia1
soluble copper
soluble nickel
soluble selenium
soluble sulfate
insoluble copper
insoluble nickel
insoluble selenium
soluble copper
soluble nickel
soluble sulfate
kg per metric ton of product
(Ib/tonl
53.5
0.145
0.0005
64.5
5
0.0315
0.06
0.11
0.0003
0.17
(107)
(0.29)
(0.001)
(129)
(10)
(0.063)
(0.12)
(0.22)
(0.0006)
(0.34)
Plant Water Use
On the average, a total of 5,300 1/kkg of product (1,270
gal/ton) is consumed and discharged at plant 299. This
includes 463 1/kkg of ground water leakage into the plant
facilities (111 gal/ton) that must be treated prior to
discharge because of contamination by process chemical«
The disposition of the water at both plants is as follows-""
water consumption
at plant no.
liters/metric ton of product (gal/ton)
302 299
evaporated
product water of hydration
mother liquor process wastes
not given
300 (72)
none
1,900
380
463
(456)
(91)
(HI)
107
-------
COPPER
SULFUR
VWSTE
COPPEF
STEAM
SULFATE/ 1
1C ACID «——•*!
SOLUTION
m— *
, RECYCLE
/ LIQUOR
WASH _..
WATER w
WATER
TO OTHER
PRODUCT
MANUFACTURE
COPPER S
£
OXIDIZER
1
EVAPORATOR
1
FILTER
1
CRYSTALLIZER
1
CENTRIFUGE
1
SCREENING
AND
DRYING
^ VENT
^ NON-CONTACT STEAM
^. SOLIDS TO PRECIOUS
^ METAL RECOVERY
^ NON- CONTACT
^COOLING WATER
^VENT
PRODUCT
TO PACKAGING
FIGURE 22
JULFATE MANUFACTURE
J PLANT 299
108
-------
ground water leakage
contact cooling
noncontact cooling
discharge
noncontact steam
condensate
sanitary
boiler feei
none
0
21,800
(5,220)
not given
3,590 (860)
463
0
463
1,350
280
(111)
(111)
(324)
(67)
No process waste waters are discharged at plant 302. The
only waters discharged are boiler blowdowns, noncontact
cooling water, and waters emerging from the barometric
condenser on the vacuum crystallizer. These waters contain
no copper salts. The condensed vapors of the crystallizer
amount to 17,900 1/kkg (4,300 gal/ton).
Waste Water Treatment
At plant 302 there are no process contact streams other than
barometric condensers. These are not treated because they
contain no copper salts.
At plant 299 there are essentially three process waste
streams emanating from the process. The mother liquor waste
stream is totally used on-site to produce another product.
The slimes are recovered and sent for reclamation of
precious metal values. The ground water leakage wastes
containing the floor washings are sumped and treated with
lime to precipitate heavy metals. The precipitates are
settled and the waste water is then discharged.
The noncontact cooling discharge and noncontact steam con-
densate are discharged without treatment.
Effluent
As all process waters at plant 302 are either recycled
lost by evaporation, there is no process water effluent.
or
Plant 299 effluent consists of the discharge of the washdown
and ground water leakage treatment system. The effluent
after neutralization and settling, achieved over a 9-day
period, consisted of an average copper content of 0.48 mg/1
with a range of 0.14 to 1.25 mg/1 and a nickel content of
less than 0.5 mg/1 for eight of the nine days. The pH of
these discharges ranged from 7.3 to 11.1. No analytical
data for selenium content is available, but a 30-day monthly
material balance on the plant for this material shows less
than 0.0005 kcr/kkg (0.0010 Ib/ton) not accounted for in the
product or in the oxidizer slimes. These values were
109
-------
mq/ror nickel.treatment ^ ^ ^/l °f C°Pper and 159
FERRIC CHLORIDE
* * PlantS in three locations in the U.S.
one-half^ol ^l ?, section Together they account for
one half of the U.S. production of this material. Four
five1 lants pr°ducers are known with a total of at least
Process Description^
li?f°r- ±S Preheated and reacted with iron, chlorine
and hydrochlonc acid to produce a ferric chloride solution.
The solution is either filtered and sold as such or filtered
and evaporated to recover a solid product. A process
™ag4an 1S S^T? "/Jsure 23 for plant 422. At plants 464
and 410 no additional hydrochloric acid is used over that in
* SOlution
-------
STEAM
P5CKLE LIQUOR*
PREHEATER
HYDROCHLORIC ACID
ill
BEACTOR
FERRIC
CHLORIDE
30U«10li
FIGURE 23
SOLUTION GRADE FERRIC CHLORIDE PRODUCTION AT PLANT 422
-------
At plants 464 and 410, there are no water borne raw wastes.
The data on sludges from the filtration step were not
available. These would be solid wastes.
Plant Water Use
At plant 422 water ia used for process sludge discharge, for
product dilution, for washdowns, and for pump seals. At
plants 464 and 410, no water other than that in the pickle
liquor is used in the process. The water use data for these
plants are:
liters/ me trie ton of ferric chloride
water consumption igal/tonl
at plant n,Qi __ 422 464 and T410
discharged with 25 (6) not given
filtration sludge
washdown 51 (12) none
seals 3,660 (878) none
consumed in product 300 (73) no additional
water
evaporated not given not given
Haste Water Treatment
At plant 422 the reactor sludge discharge is landfilled.
The filtration sludges, washdown and seal waters are treated
by settling and pH adjustment prior to discharge. A system
is planned for installation in 1974 for total water recycle,
wherein the sludges and washdown waters would be sent to a
sump to recover solids for landfill and for recycle of the
supernatant.
At plants 464 and 410 there are no waterborne wastes and
hence no waste water treatment.
At present, the effluent from plant 422 goes to a central
treatment facility for the entire complex. Due to the large
variety of products manufactured, the ferric chloride
process contribution to the total effluent cannot be
assessed. Within one year, the ferric chloride unit will
employ a closed-loop recycle system and have no effluent.
112
-------
There is no waterborne effluent from plants 464 and 410.
FLUORINE
The information on total U.S. production of fluorine is not
available because of its use in the atomic energy industry.
Proces s_Des cr ipt ion
All fluorine production is based on electrolysis from
hydrogen fluoride raw material. Two different electrolysis
processes are practiced: direct electrolysis of liquid
hydrogen fluoride (one plant) and electrolysis of fused
salts containing potassium acid fluoride, which is
regenerated with hydrogen fluoride. The latter process is
the one used for fluorine production for atomic energy,
although a new plant using the direct electrolysis of liquid
hydrogen fluoride is planned for this purpose.
Fluorine is produced at plant 203 by electrolysis of liquid
hydrogen fluoride. The hydrogen gas formed at one electrode
is vented tc the atmosphere. The fluorine formed at the
other electrode is compressed and packaged in cylinders for
sale. A process flowsheet is given in Figure 24 as it is
carried out there.
Raw Waste Loads
For the liquid hydrogen fluoride electrolysis process, there
are no solid or waterborne raw wastes produced. The process
generates a hydrogen raw waste, however, amounting to 53
kg/kkg of fluorine (106 Ib/ton) . An estimated 0.5 kkg (1.0
Ib/ton) of hydrogen fluoride gas is carried along with the
hydrogen raw waste, and is recovered by cooling to -78°C (-
108°F) and recycled to the process. A similar amount is
carried along with the fluorine stream and removed by
similar refrigeration followed by scrubbing.
Plant Water Use
No process water is used at plant 203 and there is no water-
borne effluent. The hydrogen coproduct is vented at this
facility. Non-contact cooling water is used in an amount of
9,600 to 19,200 1/kkg of fluorine (2,300-4,600 gal/ton) for
cooling purposes for the compressors. Jacket cooling only
is used and there is no effluent.
The tail gases from the process at plant 203 are treated in
the following manner:
113
-------
H
LIQUID HYDROGEN FLUORIDE*™
FLUORINE MANUFAC
FREON
NON-CONTACT
COOLING
J t
CONDPN^FR 2l
F RECYCLE T Hg.HF
_J ELECTROLYSIS F2,HF
..,
1
CAUSTIC
JftflSfSL HYDROGEN
SOLUTION VENT
—_ »^n. .nnP.n» SPENT CAUSTIC
^ oCRUBBERS • — -^ 10 tVAPORATION PONDS
f"
LIQUEFACTION
NON- CONTACT
COOLING
WATER
FIGURE 24
3TURE BY ELECTROLYSIS OF LIQUID HYDROGEN FLUORIDE
-------
1) the hydrogen liberated is cooled by noncontact methods
to -1UO°F to recover hydrogen fluoride which is recycled.
2) both the hydrogen tail gas and the tail gas separated
from the fluorine stream are scrubbed with caustic potash
solution. The caustic is recirculated several times in
the scrubber systems until nearly spent. The waste solu-
tions are then sent to an evaporation pond, from which
solids are recovered and given cff-site disposal by a
private contractor. No data has been provided on the
quantities of caustic solution used.
3) there is an emergency by-pass system for use during up-
sets in which the fluorine gas 3.3 fed into packed
columns of solid limestone,
There is no waste process contact water from the liquid HF
electrolysis process (plant 203) .
Effluent
At plant 203 (liquid HF electrolysis) there is no waterborne
process effluent. Hydrogen „ amounting to the raw waste
load, is vented.
HYDROGEN
Hydrogen is presently produced chiefly by purifying refinery
by-product gas and as a coproduct in the manufacture of
carbon monoxide. For an analysis of the latter process see
the earlier section on carbon monoxide. The plant
representing the refinery by-product process analyzed in
this section accounts for over one-third of the U.S.
hydrogen production that is not used captively.
groces s Des cr ipt ion
Crude hydrogen produced as a refinery by-product is passed
through a catalytic bed to remove oxygen and a drier to
remove the water formed by the catalytic reaction. The gas
stream is then passed through cooled gas exchangers into a
low temperature, liquid-nitrogen-cooled exchanger, through
absorbers to remove nitrogen and other impurities, and
through converters to change ortho hydrogen to the para
form. The hydrogen is then passed through a noncontact cold
helium column to liquefy it and is fed to a liquid hydrogen
storage tank, A process flowsheet is given in >igure 25.
115
-------
BY-PROOUCT FEED
NITROGEN GAS
LIQUID NITROGEN
LIQUID NITROGEN
LIQUID HYDROGEN"
CATALYST
1
DRYER
HEAT EXCHANGER
HEAT EXCHANGER
ADSORBERS
I
REFRIGERATION
RECOVERY EXCHANGER
ADSORBER
HYDROGEN CONVERTER
I
COOLER
HYDROGEN CONVERTER
COOLER
I
DISTILLATION COLUMN
I
LIQUID HYDROGEN STORAGE
METHANE GAS
'NITROGEN GAS
HELIUM GAS
FIGURE 25
HYDROGEN MANUFACTURE
BY PURIFICATION OF REFINERY BY-PRODUCT
116
-------
Raw Waste_Load
The raw wastes consist of methane and oil and grease. The
amounts, sources, and disposition of these are given below:
oil &
grease
source
absorber
com-
pressor
kg per metric ton of
product (Ib/ton)
1.65 {3.3)
1.6 x 1C-5 (3.2 x 10~5)
disposition
burned
discharged in
cooling water
Plant Water Use
The principal plant water use is for noncontact cooling
This water is the carrier of the oil and grease raw waste:
noncontact cooling
discharge
noncontact cooling
evaporated
boiler feed
sanitary
27 (6.4)
936 (224)
27 (6.4)
80 (19.2)
There is no process contact water.
down is discharged directly.
Effluent
The coolina water blow-
There is no process waste water effluent. The cooling water
blowdown average discharge is as follows:
quantity, kg per
metric ton of
product
BOD
COD
TDS
TSS
TVS
ammonia (as N)
nitrate
chloride
18
322
10
48
0,1
0.6
29
0.00012
0,00048
0.0087
0.00027
0.0013
0.000003
0.000016
0.00078
(0.00024)
(0.00096)
(0.0174)
(0.00054)
(0.0026)
(0.000005)
(0.000032)
(0.00156)
117
-------
zi (0.00216,
phenols n"L 0.000068 (0.000135,
0.00077 (0.0015U,
The chromates and zinc salts are cooling water o
inhibitors. The average PH of this discharge is 7. S
th^An^ ,Cyanide is "anufactured in the U.S. principally by
th,» Andrussow process, but also is recovered as a by-product
from acrylonitrite production. Data from two Andrussow pro-
cess plants analyzed in this section represent about one-
u one-
L of the estimated total captive and merchant production
of hydrogen cyanide in the U.S. The by-product plan?
In the Andrussow process, natural gas, ammonia and air are
reacted xn the presence of a catalyst to yield a hydrogen
e Containin9 so^ unreacted ammonia In2
pr^ss ^^ ^^ ' The —all main
2CH« + 2NH3 + 302 = 2HCN + 6H2O.
At plant 462 the residual ammonia is removed by a patented
phosphoric acid treatment as ammonium phosphates, which are
then decomposed, and the ammonia is recycled to the
catalytic reactor. The crude hydrogen cyanide is further
purifzed to remove nitriles and residual ammonia, and is
then li.quefxed and stored. This process is shown in Figure
At cj.artt 321 the residual ammonia is removed by scrubbing
wz::n sultunc acid generating a waste acid stream that is
used to maKe other products. The purification system con-
sirt-.s of a water scrubber and distillation column to remove
organic nitriles and any other impurities left after the
dcxct scrubbing. This system is shown in Figure 27.
Propylene, ammonia and air are reacted in the presence of a
catalyst to produce acetonitrile, acrylonitrile, and
nydrogen cyanide. The products are separated and the hydro-
gen cyanide is then purified, compressed, and liquefied for
118
-------
AIR
PHOSPHORIC
ACID
JRAL GAS n|>
CATALYTIC
REACTOR
1 AMMONIA
RECYCLE
AMMONIA
RECYCLE
UNIT
SULFUR
DIOXIDE
PHOSPHORIC
ACID
WATER
i
i
PURIFIER
T
WASTE
WATER
WASTE
WATER
PRODUCT
FIGURE 26
HYDROGEN CYANIDE MANUFACTURE BY THE ANDRUSSOW PROCESS
-------
T '
STEAM
'.HLrJRIC
A3ID
VWSTE
6AS
1
L WASTE
PACID
„ ACID
WASTE ACID
TO ANOTHER
PROCESS
HCN
"*i
v"^ ADSOR3ER U»»-$J DISTILLER
r J 1
T
hCN AMD I Pf.v*vr| F WWdTFR
m» wi^ L '**- "* ' v*h.s_ WH i tn
' 1
DISTILLER
WASTES
FIGURE 27
SIMPLIFIED FLOW DIAGRAM OF HYDROGEN CYANIDE
MANUFACTURE AT PLANT 321
*fic»>ucT
-------
sale. A process flowsheet is given in Figure 28 as it is
practiced at plant 229.
Raw Waste Lgads
-a
passing from the reactor.
The data tor plant 321 are given below in comparison to the
IvLaae data for plant U62 to show the impact on raw waste
load of ?he deferent purification schemes for the Andrussow
process:
waste material
21
hyaro?en cyaniae 0.60 (1 2, 1 . (2.8,
ammonia ,A ,on? 1 75 (3
"
phosphates
ammonium sulfatfi If 250 (2,500) —
hydroqon cyanide 0-3 (0.6)
For the acrylonitrile by-product process, there are no solid
or waterborne wastes generated. All tail gas streams are
burned to destroy hydrogen cyanide before venting to the
atmosphere.
£lant_Wate£_ Use
The two Andrussow process plants consume the following aver-
age amounts of water:
water consumption
total consumption 17,000 (4,070) 58.600
process waste 4,500 (1,080) ™l*** 0("'
ncontact cooling 5,920 (1,420) 7,9/0 (1,910)
121
-------
ro
ro
REFRIGERATED BRME
(NON-CONTACT)
M
IMPURE HYDROGEN
CYANIDE FEED-,
(BY PRODUCT) \
7. ACRYLONITRILE Jl ^JT,
AMMONIA ««=«««J^ PLANT B«B"™|£3
PROPYLENE «™»g^
ACETONITRILE
ACRYLONITRILE
CONDENSER
^TO FLARE
^-REFUIX
PURIFICATION
TOWER
NON-CONTACT
SEAL WKTER STEAM
TT n
it*— PI t*i£T* •• tTa RFBfMI F R
Krj[ RETURN TQ
PR2S£fr ACRYLONITRILE
LKHJD ^T
FIGURE 28
HYDROGEN CYANIDE PROCESS FLOW DIAGRAM FOR PLANT 229
-------
Table A. Raw Waste Loads in Kilograms per Metric Ton of Product
(Ib/ton) from Andrussow Process at Plant 462
INi
00
Waste
Products
Plant 462:
hydrogen
cyanide
ammonia
nitriles
(BOD)
sulfates
phosphates
Operation
average range
1.4 0.7-2.1
(2.8) (1.5-4.1)
5.8
(11.5)
1.75
(3.5)
12.5
(25.0)
0.5
(1.0)
4.2-15.2
(8.4-30.3)
0.8-2.6
(1.5-5.1)
5.1-25
(10.2-50)
0.25-1.3
(0.5-2.5)
Start Up Shut
average
0.75
(1.5)
20
(40)
0.5
(1.0)
range
0.5-1.0
(1.0-2.0)
15.2-25.3
(30.4-50.5)
0.25-1.0
(0.5-2.0)
average
3.0
(6.0)
11.3
(22.5)
2.0
(4.0)
2.8
(5.6)
22.5
(45)
Down
range
2.6-4
(5.1-8.0)
5-20
(10-40)
1-3
(2-6)
1.5-3.5
(3-7)
10-30
(20-60)
-------
boiler feed
evaporation
washings
1,230 (296)
U,030 (965)
87 (21)
not given
not given
At both plants, rioncontact cooling water flow is 98-99
percent recycled. The above values are the makeup, not the
total flow. About 2,000 liters of water per kkg of hydrogen
cyanide (U80 gal/ton) are generated by the chemical reaction
in this process and are part of the above process water.
At the acrylonitrile by-product plant (229) no process water
is used, and the noncontact cooling water and pump seal
water are totally recycled.
Ha,ste Water Treatment
All of the wastes from the Andrussow process and other
cyanide-containing streams from other plant 462 processes
are fed into a treatment pond, where sodium hydroxide and
chlorine are added to oxidize the cyanide present to
cyanate, and to remove suspended materials. After this
chlorination treatment, the waste waters are discharged.
At plant 321, the distillation bottoms are sent to the plant
complex treatment system. This consists of API oil separa-
tion, neutralization, biological oxidation, chemical floccu-
lation, clarification and filtration. As there are no solid
or liquid wastes at plant 229, no water treatment is
required.
Bf fluent
The composition of the Andrussow process waste stream before
and after treatment, in mg/1, where appropriate, is:
Concentrat ion,
mg/ \,f_ where apEropriate
Process Raw Final
Waste Stream Effluent
Calculated
Average
Quantity of
Effluent
Material
kg/metric
ton__(lb/tonl_
TSS
TDS
pH
chloride
20 (15-50)
1000 (900-
1300)
2.7 (2.5-3.5)
2 (0-U)
20 (15-50) 1.0 (2.0)
1000 (500- 50.6 (101)
1200)
9.1 (8.5-
9.5)
300 (50-
400)
15.2 (30
124
-------
sulfate 250 (100-400) 150 (20- 7.6 (15.2)
500)
sodium 0-4
iron 3.0 (2-4) 0.15 (0.3)
copper 0.07 (0- 0.004
0.2) (0.007)
acidity (total) 200-400
chlorine 0.4 0.02 (0.04)
phosphates 10-30 1 (2)
oxidizable cyanide 27 (13-41) 0.01 0.0005
(0.001)
total cyanide 28 (14-42) 2.0 0.05 (0.1)
ammonia 4.3 (8.6)
Effluent pH is in the 8-9.5 range. The slight alkalinity is
due to the need for alkaline conditions to safely destroy
HCN with chlorination.
The complex effluent for plant 321 is at pH 6-9. The
treatment system removes about 80 percent of the COD waste
load and 80 percent of the organics.
There are no waterborne or solid effluents for the by-
product process at plant 229. The combustion products of
the tail gas flare are an airborne effluent.
IODINE
Two plants in different locations in the U.S. manufacture
iodine from iodide-containing brines. These account for all
of the U.S. production. Both plants use the same general
process. The analysis in this section is based on the
details of one of these plants. At plant 239 the process
for manufacture of iodine is based on extraction from
chloride brines containing about 0.004% iodine.
Process Description
The brine is acidified with hydrochloric acid and fed into
an extraction unit where chlorine is passed through the
brine. In this step iodine is liberated. The free iodine
is stripped from the brine by a current of air, which is
then passed through a column of water containing dissolved
sulfur dioxide. The resulting iodide solution is again
treated with chlorine to liberate iodine as a solid, which
is collected by filtration and sent to a melting kettle.
There it is melted under sulfuric acid and recovered from
the acid, crushed and packaged for sale. An overall process
diagram for the iodine recovery system for this facility is
shown in Figure 29.
125
-------
CHLORINE
PURIFIED __
BRINE
AIR
1 JI
HYDROCHLORIC ACID
BLOW-OUT
TOWER
STRIPPED BRINE TO
OTHER PLANT USE
OR WASTE
COOLING WATER
E
AIR PLUS IODINE VAPOR
COOLER
IODINE
ABSORPTION
TOWER
WATER
SULFUR DIOXIDE-
TREATING
TANK
CHLORINE
FILTER
SULFURIC ACID
1
KETTLE
COOLING
COOLER
i
FILTER
CRUSHER
PRODUCT
STRIPPED AIR
SOLUTION TO BRINE
PURIFICATION SYSTEM
OR OTHER PLANT USE
SOLUTION TO BRINE
.PURFICATION SYSTEM
OR OTHER PLANT USE
FIGURE 29
IODINE MANUFACTURE
126
-------
Raw_Waste_Loads
are:
£aw_ waste _jnat gjcial s
spent brine solids ''I77?!™ <13'555'2°0)
brine solids from leaks not qiven
and spills
Th,.«o waatPM are passed t.o another procosfi that extracts
Snor component and' is then Bent to t matrn.nt and dxsponal.
W^ter is used principally for two process purposes: brine
dilution and noncontact cooling:
brine dilution 888 000 (213,000,
other process water 23,00 0 ( 5.000)
noncontact cooling 275,000 ( 66rOUO,
m Addition to this, 16,870,000 1/kkg of product (U, 040, 000
'al/tonj enter the proems as the brine from the wells.
enH waters are panned on to another extraction
t
their Bourne .
include installation of a system for
to allow for repairs.
Only noncontact cooling water is discharged.
TRQN BLUES
127
-------
As a rule, iron blues pigments are manufactured in inorganic
pigment complex facilities and part of the output is used
internally to manufacture mixed pigments such as chrome
green, which was covered in the Chrome Pigments section.
Iron blues pigments are discussed separately because their
wastes are quite different chemically from those of the
chrome pigments. The information in this section is based
on the analysis of three iron blues plants which account for
the U.S. production of this material. The two principal
chemical forms of the pigment are ferric ferrocyanide and
ferric ammonium ferrocyanide.
Description of Processes
At all three plants ferrous sulfate is reacted with sodium
ferrocyanide in the presence of ammonium sulfate. The white
precipitate thus formed is oxidized to the blue pigment in
the presence of sulfuric acid generally with sodium
chlorate. Product separation and washing is universally
carried out with a filter press. This process as integrated
in an inorganic pigments plant is shown in an earlier
section in Figure 13.
Raw Waste Loads
The raw wastes from iron blues manufacture originate from
the filtering and washing operations and from washdown of
pigment particulates from grinding and packaging areas. The
data as given from these plants are:
kg per metric ton of product (Ib/ton)
279 370 467
present
not given
not given
present
not given
not given
present
1,090 (2,180)
unknown
214 (428)
50 (100)
1,000 (2,000)
not given
300 (600)
20 (40)
waste material
at plant no.
sodium sulfate
sodium chloride
ammonium sulfate
ferrous sulfate
or iron residues
(as Fe)
sulfuric acid
hydrochloric acid
iron blues pig-
ment particulates
*When sulfuric acid is used, hydrochloric is not and vice
versa.
Chloride raw waste loads which must result from the
oxidation of ferrous ferrocyanide by sodium chlorate were
not given as such by the plants claiming the use of sodium
543 (1,086)
unknown
330 (660)*
320 (640) *
not given
128
-------
chlorate. Similarly, pigment particulates (product pigment)
must be present at least as occasional spills and cleanups,
but were not given as such. The pigments particulate raw
waste load at iron blues plants is estimated to be 25 Jcg/kkg
of product (50 Ibs/ton) .
Plant Water Use
The principal consumption of process- related water at iron
blues plants is for process waste water discharge. The
valuer, of the several uses are:
water consumption ^iterspejr metric ton (gal/ton)
279 ~ 570 467
process waste not not 72,800
separable separable (17,450)
gas scrubber — 26,000
discharge (6,300)
evaporated not not 6,350
separable separable (1,520)
contact cooling none none none
noncontact cooling none none none
The hydraulic loads for iron blues at plants 279 and 370 are
not separable from the chrome pigments complex to which the
plants are attached except for the value given for the off-
qas scrubber at plant 370.
Waste, water Treatment
At plant 279 the iron blues wastes are treated with slaked
lime to raise the pll and precipitate sulfate as gypsum.
This is settled by ponding. The pigment particulates were
not well settled out ac> determined by visual observation of
the pond and overflow, which is common to the whole pigment
complex.
At plant 370 the waste streams are also neutralized with
lime and fed to a settling lagoon prior to discharge.
Planned further treatment here is installation of clarifiers
and filters to further remove suspended materials, with
landfill of solids. This treatment system is also a pigment
complex combined system.
At plant 467, a similar pigment complex, treatment involves
equalization, neutralization with lime and clarification.
This is 90 to 95 percent effective in removing lead,
chromium, iron and cyanide.
129
-------
Effluents
At plant 279 no effluent data is available except for the pH
range of 5.5 to 8.5.
At plant 370 the complex effluent has a pH range of 6.5 to
9.0 and an iron content of 0.2 to 2.0 mg/1, with an average
value of 1.0 mg/1. This amounts to an estimated 0.3 kg/kkg
of iron blues production (0.6 Ib/ton), which is over a 95
percent reduction of the raw waste load.
At plant 467, the treated pigments complex effluent per the
COE permit application data has an iron discharge equivalent
to less than 3 kg/kkg of iron blues production (6 Ib/ton).
If this is all attributable to the iron blues process, the
treatment reduction in iron was 85 percent. Probably some
minor quantities of iron come from other sources.
LEAD MONOXIDE (LITHARGE)
The data analyzed in this section are from two plants that
use the same basic process, the furnace oxidation of lead,
but have some significant differences in their operations.
These account for an estimated 40 percent of the total U.S.
production of litharge. The two plants differ in size by a
factor of roughly 4. This, however, does not affect the
presence or nature of pollutants in the effluent.
Process Descriptions
At plant 3U1 lead suboxide (Pb2O) is first prepared by the
Barton Oxide Process which involves the injection of molten
lead into an atomizer with air and the collection of the 1-
40 micron sized particles (3-6 micron average) of suboxide
in a series of cyclones and settling chambers. Dusts are
controlled by dry bag collectors. The suboxide is then fed
to a reverberatory type furnace operated at approximately
649°C (1200°F) where it is oxidized to litharge (PbO). The
furnace is discharged through a water cooled screw conveyor
dropping the temperature of the material to below 300°F to
prevent the formation of red lead (Pb3O4_) . The cooled
material discharged from the furnace is collected to a
storage hopper, milled to size and stored for shipment.
Dusts are controlled throughout the process by the use of
cyclones and dry bag collectors. No process water is used.
Indirect cooling water is used for cooling the oxide in the
furnace discharge conveyor as noted above. A process
diagram is given in Figure 30.
130
-------
MOLTEN LEAD <
AIR mtumtmmm
ATOMIZER
CYCLONE
PRODUCT
COOLING
1
SETTLING
CHAMBER
FURNACE
I
I
STORAGE
BIN
I
MILL
CYCLONE
CYCLONE
F
5XIDE
SUBOXIDE
PRODUCT
STORAGE
1
¥
BAG HOUSE
VENT
BAG FILTER
PR
VENT
OXIDE PRODUCT
(LITHARGE)
FIGURE 30
LITHARGE MANUFACTURING PROCESS
AT PLANT 341
131
-------
At plant 367 a mixture of powdered lead and partially
oxidized powdered lead is melted and oxidized with air in a
furnace to form lead monoxide directly. This is discharged
by a water cooled screw conveyor to the milling operation.
The product is discharged through a bag collector for
storage, use, sale or further processing into a superfine
grade. Washdown of dusts from plant surfaces is practiced
at this plant, whereas, at plant 341, floor dust is dry
vacuumed. A process diagram for plant 367 is given in
Figure 31.
Raw Waste Loads
The raw wastes at these plants for this process are the
plant surface dusts consisting of lead oxides. The data
given are:
waste material kg per metric ton of litharge_jlb/tonl.
at plant no. __ lii
lead oxides (PbO, not known 10 (20)
Pb304)
Plant Water Use
At both plants the screw conveyors are noncontact water
cooled. There is no water involved in the process itself.
The other use of water is for washdown of plant surfaces at
plant 367:
water consumption lj±gr^!!!!g±rin *"on of litharge (gal/ton)
at plant no. __ 341
washdowns none unknown
noncontact cooling 6.5 (1.6) est. 2,400 (10,000)
discharge
The washdown water at plant 367 is sent to a sump for
settling.
Waste Water Treatment
There is no process contact water for plant 341, so no
treatment is necessary.
At plant 367 the sumped washdown water is combined with
waste waters from other lead chemicals manufacture and sent
to a settling pond. This stream contains sulfate, which
precipitates soluble lead as lead sulfate. This overall
132
-------
PIG LEAD
AIR
COOLING WATER
MILL
ROTARY
OXIDIZING
FURNACE
COOLER
MILL
COLLECTOR
AND
STORAGE
"VENT
•^PRODUCT POWDER
HIGH SPEED
MILL
COLLECTOR
AND
STORAGE
PRODUCT
( ULTRA FINE POWDER)
VENT
FIGURE 31
LEAD MONOXIDE PRODUCTION AT PLANT 367
133
-------
treatment is reported to be 85-90 percent effective in
reducing the lead waste content«
Effluent
At plant 341 there is no waterborne effluent. Airborne dust
wastes are removed by the dry bag collection devices and re-
used. There are no solid wastes requiring disposal.
At plant 367 the composition of the complex effluent stream
as given by the data from the COE permit application and the
quantities of materials discharged on the basis of the total
production of lead chemicals are:
quantity of waste material,
. kg per metric ton of total
concentration, lead chemicals production
mq/1 (Ib/ton)
TSS 3 0.04 (0.09)
TDS 941 14 (27)
lead 1.0 0.015 (0.029)
sulfate 31 0.45 (0.90)
chloride 447 6.5 (13)
The pH of this effluent is 9.9.
LITHIUM CARBONATE
Lithium carbonate production in the U.S. is from two
sources: production from the Trona process and a single
plant that produces from spodumene ore. The former is
discussed in the section on the Trona process. This section
discusses the latter plant and process.
Process Description
Plant 273 is the only plant using this process. While the
data from this plant is minimal, the following gives the
essential process information (2) .
"In this process, spodumene is reacted with sulfuric acid to
form lithium sulfate, according to the patent of Ellestad
and Leute. Since natural a-spodumene is essentially
unattacked by sulfuric acid, the first step is the
conversion of the ore to the more reactive b-spodumene by
heating to 1075-1100°C in a kiln 250 ft long. The kiln
discharge is cooled, ball-milled to minus 100 mesh, and
mixed with 66° Be sulfuric acid (93%) equivalent to the
lithium, plus a moderate excess. This mixture is heated in
134
-------
a kiln to approx 200-250°C for a brief period, causincr a
chemical reaction in which hydrogen ion replaces the lithium
ion in the mineral, forming soluble lithium sulfate, but
leaving the ore residue virtually insoluble.
The acid-roasted ore is leached with water and the excess
acid is neutralized with ground limestone. Filtration
results in an impure lithium sulfate solution, saturated
with calcium sulfate. Treatment with hydrated lime and soda
ash removes calcium and magnesium. The purified solution is
adjusted to a pH of 7-8 with sulfuric acid, followed by
concentration in a five-effect evaporator to about 200-250
g/liter of lithium sulfate. Moderate amounts of sodium
sulfate and lesser amounts of potassium sulfate are also
present. After filtration, lithium carbonate is
precipitated at 90-100°C by the addition of a strong soda-
ash solution. The precipitated lithium carbonate is centri-
tuqed, washed, and dried. Approximately 15^ of the lithium
remains in the mother liquor, together with large amounts of
sodium sulfate. Cooling to 0°C precipitates the greater
part of the sodium sulfate as the decahydrate (Glauber's
salt), which is converted to the anhydrous salt, and sold as
a by-product. The mother liquor from the Glauber's sa14:,
containing the unrecovered lithium, is recycled to the ore-
leach system."
This process is shown in Figure 32.
Raw Waste Load
The raw wastes consist of sultates of calcium, lithium, and
sodium, and ore residues.
Plant Water_Use
The process contact waters for this process average approxi-
mately 36,000 1/kkg of product (8,600 gal/ton). Other plant
water uses are noncontact.
Waste water Treatment
The process contact water is combined with other process
waters from other on-site processes and treated by limestone
neutralization and settling prior to discharge.
Effluent
The plant effluent attributable to this process contains
suspended solids and dissolved solids at pH 7.0 to 7.a.
135
-------
CONCENTRATED
SPOOUMENE ORE
SULFUR 1C AC ! D
WATER AND
LIMESTONE
WATER
CALCIUM
HYDROXIDE
SODA ASH
SODA ASH
KILN
KILN
I
COOLER
GRINDING
1
ACID MIXER
NEUTRALIZATION
I
LEACH
i
F!LTER
FILTER
EVAPORATOR
FILTER
I
VENT
DUST
COLLECTOR
ACID ROASTER ^ SCRUBBERS j
WASTE
ORE
RESIDUES 1
MEUTRALIZATION
WASTE
VENT
ALUMINUM
HYDROXIDE
PRECIPITATION TANKJ
WASTE LAGOONS
SOLIDS
CENTRIFUGE
. OUUI
ft
MIXING TANK
CENTRIFUGE
CRYSTALLIZERJ
*
EVAPORATOR
DRYER
SODIUM
SULFATE
t
VENT
LITHIUM CARBONATE PRODUCT
FIGURE 32
PRODUCTION OF LITHIUM CARBONATE FROM
SPODUMENE ORE
136
-------
Four plants are responsible for the U.S. production of
nickel sulfate. The two whose data are included in this
rinalysis produce at least 50 percent of this. One of the
remaining two plants produces only reagent grade in
relatively small quantities (less than 5 percent of U.S.
production).
Process Descrii
Nickel sulfate at plants 213 and tt!9 is produced from two
types of raw materials:
1) pun- nickel or nickel oxide;
2) impure nickel-containing materials; e.g., spent nickel
catalysts or nickel carbonate made by addition of soda
ash to spent nickel plating solutions.
In the first case, the metal or oxide is digested in
sulfuric acid and the solution is then filtered and either
packaged for sale or further processed to recover a solid
material, the hexahydrate. The sludges recovered by
filtration can be sent to the second process to produce more
nickel sulfate.
In the second case, the raw materials are also digested in
sulfuric acid. However, the resulting solutions have to be
treated in series with oxidizers, lime and sulfides to
precipitate impurities. These solutions are filtered and
marketed aa such or further processed to recover a solid
product. The recovered sludges from filtration are treated
as solid waste.
To recover solid product, the nickel sulfate solutions are
first concentrated, then filtered and fed to a crystallizer.
The resjlting suspensions are fed to a classifier where
solid product is recovered. This material is then dried,
cooled, screened and packaged for sale. The recovered
solids from the filtration step and mother liquor from the
classifiers are recycled to an earlier part of the process.
A generalized process flowsheet for plant 213 is given in
Figure 33. It is similar to plant 419.
Raw Waste Loads
Raw wastes given for plant 213 consist of various filtration
muds and the filtrates from digestion and soda ash treatment
of spent plating solutions:
137
-------
NICKEL
POWDER <
NICKEL-
OXIDE
SOLUTION
PRODUCT
DIGESTOR
I
STEAM
• SULFURIC
ACID
SPENT NICKEL
STEAM
ACID
STEAM
AIR
LIME
SULFIDE
_M * * l.rrt ,^.?
151 DIGESTOR LJ ""
i
TREATING TANK g
. I**"" '
j FILTER | m
H- * ,
_J3 TREATING TANK
t ,__
^
FILTER
SPENT PLATING SOLUTION
SODA ASH
QC LAB
LIQUOR
IT NICKEL
RESIDUES
EFFLUENT
SULFURIC ACID
OXIDIZER
CALCITE
> SLUDGE
> SLUDGE
CONCENTRATOR
STEAM
FILTER
WrfEVAPORATICIN TANK
CRYSTALLIZER
COOLING
WATER
CLASSIFIER
HOLDING TANK }
i
DRYER
DUSTS
1
COOL, SCREEN,
PACKAGE
SCRUBBER
DUSTS
f
SOLID PRODUCT
STEAM
WATER
FIGURE 33
GENERALIZED PROCESS FLOW DIAGRAM FOR
NICKEL SULFATE PRODUCTION AT PLANT 213
138
-------
waste material
kg ger metric ton of product (Ib/tonS
0.052 (0.103) expressed
as nickel
muds of heavy metal 243 (486)
salts from purification
treatment filters
nickel carbonate and
miscellaneous salts
from filtrate of soda
ash treatment of spent
plating solutions
The latter raw waste exists primarily when spent plating
solutions are used as raw material.
The raw waste information for plant 419 is that the wastes
from purification of spent plating solutions contain
dissolved nickel, suspended solids, dissolved solids, and
small amounts of organics.
Plant Water Use
Plant water consumption at plant 213 includes an average of
24,500 of municipal water/kkg of nickel sulfate product
(expressed as the hexahydrate) (5,860 gal/ ton) plus such
water which enters with the raw materials. The water is
consumed on the average in the following ways:
water consumption
at plant no.
liters/metric ton of product (gal/ton)
213 419
process evaporation and
consumed in product
process waste discharge
from plating solution
treatment
QC lab and miscellaneous
discharges
noncontact cooling and
tower blowdown
cooling tower evaporation
boiler feed
barometric condenser
water
Plant Water Treatment
2,450 (590)
1,150 (280)
3,250 (780)
12,290 (2,945)
3,600 (860)
1,730 (410)
not given
present
not given
present
present
present
The primary process wastes discharged from both plants are
from the pretreatment of spent plating solutions. If such
139
-------
raw materials were not employed, there would be little
process discharge.
Treatment of the process waste waters at plant 213 consists
of pH adjustment to precipitate nickel salts followed by
sand filtration to remove the precipitates. The treatment
achieves 79 percent reduction of nickel content of the waste
stream. After the sand filtration system, the waste stream
is then combined with other plant waste streams, all of
which are discharged via a single outfall,
Effluent
The pH and nickel content at plant 213 of the intake water,
the untreated process waste water stream and the stream
emerging from the sand filtration systems are, respectively:
pH: 7.0, 8.2, 10.2
nickel (mg/1) : 0.01, 12.2, 3.0
Plant 419 has no discharge when using raw materials other
than spent plating solutions.
NITROGEN AND OXYGEN
The data from three plants producing nitrogen and oxj^an uv
liquefying from air are analyzed in this section. In total
they produce annually approximately 590,000 kkg of oxygen
and nitrogen (650,000 tons). This amounts to approximately
5 percent of the U.S. commercial sales of nitrogen and 2
percent of the commercial sales of oxygen. There are 139
plants in the U.S. using this process.
Process Descriptions
This process is based on the distillation of liquefied air,
hence, both oxygen and nitrogen are produced. Air is com-
pressed, cooled in countercurrent heat exhangers and then
separated into nitrogen and oxygen by distillation. Both
products are usually sold as liquefied material. A process
diagram is given in Figure 34. The process at the two other
plants is essentially the same. At plant 289 nitrogen and
oxygen are produced in equal quantities by weight and at
plant 457 in nearly equal quantities.
Raw Waste Loads
The raw wastes from the process consist of cooling tower
blowdowns, cooling tower filter backflush, compressor
condensate, boiler blowdown and water softener regenerants
140
-------
AIR
1
BACKWASH
i
COLD BOX
CONDENSATE
WATER 1
FILTER
WATER
COOLING
TOWER
... . . ..
1 i
RECYCLE
PRODUCTS.
NITROGEN
OXYGEN
SLOWDOWN
FIGURE 34
FLOW DIAGRAM FOR MANUFACTURE OF OXYGEN AND NITROGEN AT
PLANT 289
-------
normally associated with treatment of toiler water. The
values for the waste materials from these sources at the
three plants are:
waste
material
at plant no.
oil & grease
minerals
source
289
296
and O2 (Ib/ton)
457
caustic
comcrassor
cooling
tower
blow-down^
filter
backwanh
air
scrubber
quantity 0.011 (0.022)
unknown
0.5 (1.0)
Plant Water Use
Water used in plant 289 amounts to an a-orage of 2,340 1/kkg
of combined product (560 gal/ton) , obtained fior municipal
water. In addition, water is obtained as condensate from
the air compression, averaging 38.4 1/kkg (9.2 gal/ton).
The use of municipal water is in noncont~ct cooling and in
boilers.
At plant 296 nor.contact cooling consumes 21,900 1/kkg of
product (5,240 gal/tern)- There is also approximately 7.6 of
condensate/kkg of product (1.8 gal/ton) .
Water use at plant U57 is for nonconta^t err ling and for
sucker plant air scrubber solution. The quantities
summarized with thos?-: of the other plants are:
water consumption
atplant no.
cooling tower
blowdown and
filter backwash
cooling tower
evaporation
and windage
boiler blowdown
per metric ton of product (Ib
~ ' 296
(ICO)
21,900
(5,240)
:.,S30 (438) none
20 (5)
U57
54 (13)
1,455 (349)
142
-------
sodium 225
turbidity 0.5
color 10
total alka- 28
linity
(as CaCO3)
phosphate 0.2
(as P)
tempe ra ture 85
(OF)
COD 30
BOD 1
sulfite 2
338
72
0.5
5
98
0.1
0
2
2
0.103 (0.206)
0.013 (0.026)
0.00009(0.0002)
0.014 (0.028)
0.0005 (0.0009)
0.0009 (0.0018)
At plant 296, the effluent from the oil trap system contains
6 to 9 mg/1 of oil. This amounts to from 0.09 to 0.14 kg of
oil/kkg of product (0.18 to 0.28 Ib/ton).
The only discharge from plant 457 is the cooling tower blow-
down which, as given in the COE permit contains chromium
and zinc. These are the residues of cooling water treatment
chemicals.
POTASSIUM CHLORIDE
Potassium chloride is produced in the U.S. by two principax
processes: extraction from sylvite ore and extraction fro."
lake brine (Trona process). For a description of tn^
latter, see the section concerning the Trona process. The
sylvite ore process is restricted geographically, the six
plants using it being located in New Mexico. The two given
herein are currently producing a total of approximately
700,000 kkg/yr (770,000 tons) which is an estimated 45
percent of the production from this source. The plants are
roughly similar in output.
Prpcess Description
Sylvite ore is a combination of potassium chloride and sod-
ium chloride. The ore is mined, crushed, screened, and wet-
ground in brine to facilitate its liberation. The ore is
separated from clay impurities in a desliming process and
the clay impurities are fed to a gravity separator which
removes some of the sodium chloride precipitated from the
leach brine and insolubles for disposal as waste. After
desliming, the ore is chemically treated in preparation for
a flotation process, where potassium chloride is separated
from sodium chloride. The tailings from the flotation step
are wasted and the resulting potassium chloride slurries are
144
-------
steam
scrubbing
nolut ion
65 (16)
none
nont1
condens.ite 38.4 (9.2) 7.6 (1.8)
Waste Water Treatment
4 (1)
not
At plant 289 the cooling tower blowdown and compressor con-
densates are discharged from the plant into a stream without
treatment. Boiler blowdown and water softener regenerants
are directed to a small pond. There is no process contact
water other than the compresssor condensate.
At plant 296 a stream of 15,200 1/kkg of product (3,640
gal/ton) composed of condensate, oil, and some cooling ^ater
IB sent through a aeries of ponds arid weir darns to trap the
oil. The rer.t of the hydraulic load is diacharged directly.
At plant 457 the cooling tower blowdown is discharged
without treatment. The air scrubber solution is collected
in tanks and sold for itu caustic content. The oil and
grease from the compressors is collected in drums and hauled
away by a contractor.
Effluent
At plant 289, the compressor condensate amounts to 38.a
1/kkg (9.2 gal/ton) and contains no solids c. OL er
materials. The discharge from the plant contains this flow
plus cooling tower blowdown and filter backwash, totalling
459 liters per kkg (110 gal/ton) on the average. The
composition of this effluent compared to intake water
composition in shown below as given in the COE permit
application data. The principal changes in water
composition are an increase in disnolved solids and an
increase in ron duo to water treatment with organic
chemicals.
constituents
(mg/1 where
appropriate)
TSS
TDS
PH
chloride
sulfate
effluent
avg.
10
1142
6.7
380
120
intake
water
15
1715
7.4
570
180
4
236
7.3
165
6
calculated
effluent quantity,
kg per metric ton
lib/ton)
0.0046 (0.0092)
0.524 (1.05)
0.17
0.055
(0.35)
(0.11)
143
-------
centrifuged to recover potassium chloride. The product is
then dried, screened and packaged. The liquors from the
centrifuge are recycled to the flotation circuit. A
generalized process flowsheet appears as Figure 35.
Raw Waste Loads
The raw wastes consist largely of sodium chloride and insol-
uble impurities (clay, silica, etc.) present in the sylvite
ore. Below is a comparison of the raw wastes of two plants.
Raw material differences between the two plants account
largely for the differences in the clay, magnesium sulfate
and potassium sulfate raw wastes.
waste material kg ,per metric ton of product (Ib/ton)
Slant 474 plant_280
Nad (solid) 3,750 (7,500) 2,500 (5,000)
NaCl (brine) 1,400 (2,800) 1,000 (2,000)
KC1 (brine) 75 (150) J18 (635)
MgS04 640 (1,280) 75 (150)
K2SO4 440 (880)
Clays 75 (150) 235 (470)
A small portion of the wastes at plant 474 are sold.
Plant Water Use
Water use at both plants is principally as process water:
water input;
liters per metric ton of product jgaI/ton)
plant 474 Elarvt_2<8J)
fresh water 6,420 (1,540) 1,750 (421)
brine water ^ 3,160 1760)
total water input 6,420 (1,540) 4,910 (1,180)
water use:
process, recycled 34,600 (8,310) LI,900 (2,860)
process, waste 6,420 (1,540) 4,710 (1,130)
boiler feed none 205 (50)
contact cooling 0 o
noncontact cooling 0 o
total water consumption 6,420 (1,540) 4,915 (1,180)
145
-------
-p.
en
SYLVITE
ORE
1°T£ BRINE RECYCLE
1
CRUSHING
AND
GRINDING
— *»
WATER
I T
DESL1MING
AND
SEPARATION
— »i
FLOTATION I
CHEMICALS 1
FLOTATION
_ »i
^
DEWATERING
SLIMES
1 TO WASTE
BRINES
TO WASTE
OR TO RECYCLE
LEGEND:
NOT PRESENT AT BOTH PLANTS
TAILINGS
WASTE
AND
BRINE
VENT
DRYING
SCREENING
\
PRODUCTS
FIGURE 35
GENERALIZED PROCESS DIAGRAM FOR POTASSIUM CHLORIDE MANUFACTURE
FROM SYLVl'iE ORE
-------
Plant Waste Treatment
All waste streams from the process are disposed of on the
ground surface with the exception of the wastes sold from
plant
Plant Effluent
There is no effluent discharged from the plants to
waterways. The geographical location of the raw materials
used in this process establishes the discharge criteria for
this process.,
POTASSIUM IODIDE
Two plants account for the total U.S. production of
potassium iodide. The data from both have been analyzed and
that of one cited in detail below. The other resembles in a
general way the one used at the described plant.
Procggs_Degcription
At plant 368, iodine crystals, potassium hydroxide and
distilled water are mixed in a reactor, wherein potassium
iodide and iodate are formed. The iodate precipitates out
and is further processed as a by-product. The iodide
solution is evaporated to dryness and fused in a gas fired
furnace to decompose residual iodates and any organic
matter. The iodide is redissolved in distilled water and
treated with small amounts of barium carbonate, potassium
carbonate, hydrogen sulfide, ferrous iodide and carbon
dioxide for pH adjustment and to precipitate trace
impurities. The solution is filtered into a second treating
tank, given a second pH adjustment, if necessary, refiltered
and piped to a series of steam heated crystallizers. The
slurry leaving the crystallizers is centrifuged and the
potassium iodide crystals are dried, screened and packaged
for sale. The mother liquor from the centrifuge is recycled
to the initial treatment tank. The process diagram for the
manufacture of both potassium iodide and iodate is shown in
Figure 36.
At plant 196 iodine and caustic potash solution are the raw
materials also.
Raw Waste Loads
Raw wastes from the plant 368 iodide process include a solid
waste consisting of precipitated impurities and filter pads
147
-------
IODINE .-.-..—
CAUSTIC POTAS'i
PISTiLLED
REACTOR
^ _^-™™,,^j5^
agjj '••••i I
i L
IODATE
REDISSOLVER
IODIDE
SOLUTION
SEDISSQLViNG •
WATI:R
FUSING POT
TOR PH
K2CCo 1 ADJUSTMENT
F,"j(>
"
f IMPURITY
! PRECIPITATION
TREATING TANK
SOLID
SOL:J> w/ STE «o-
STEAM —
(RECYCLED)
FILTER
TREATING TANK
FILTER
cc
O
g
.j
K
?
5
CRYSTALLIZER
CENTRIFUGE
V
>
DRYER
PRODUCT
FILTER
DRYER
POTASSIUM
IODATE
CO-PRODUCT
1
•»
SOLID WASTE
BRINE COOLING
SYSTEM
FIGURE 36
POTASSIUM IODIDE PROCESS FLOW DIAGRAM
AT PLANT 368
148
-------
amounting to 15 kg/kkg (30 Ibs/ton) of product and a waste
water stream of about 125 to 167 1/kkg of product (30 to 40
gal/ton of product) containing less than 0.5 kg/kkg (1.0
Ib/ton) of dissolved potassium iodide and iodate resulting
from the washdown of product spills.
Plant ffater Use
At plant 368 the total water input from the municipal water
supply averages 6,420 1/kkg (1,540 gals/ton) of product.
Most of this (up to 6,300 1/kkg) is lost to the atmosphere
by evaporation, after having been used as boiler feed and
the resultant steam condensate being as process water for
dissolving. The waste water strean» from washdown of spills
is 125 to 167 1/kkg (30 to 40 gal/ton).
Plant 496 has a significant noncontact cooling use of water,
as well as evaporation and washdown discharge. This latter
is larger than that given for plant 368. Also waste water
is discharged with purification sludges. Process waste
water discharged is 1,200 1/kkg (290 gal/ton) .
Waste Water Treatment
At plant 368 the only waste water is the washdown which is
discharged to an evaporation pond without treatment. The
solid wastes are not treated, but are removed by a
commercial solid waste disposal contractor.
At plant 469 the process waterborne discharges consisting of
shutdown washes and purification sludges are discharged
without treatment.
Effluent
All waterborne wastes at plant 368 are sent to an
evaporation pond. There is no waterborne effluent from this
pond, the location being a low rainfall region. Sanitary
wastes are sent to the municipal sewer. Boiler blowdowns
are discharged to the evaporation pond. The process waste
water discharge to the evaporation pond consists of the
washdowns of product spills containing an estimated average
based on the raw waste:
concentration, kg per metric ton
constituent mg/1 of product
KI + KIO3 3,400 0.5 (1.0)
149
-------
The effluent from plant 469 contains both the washdown raw
wastes and the purification sludges.
Three significant plants produce silver nitrate in the U.S.
Two of these are discussed in this section and they account
for over 9GS of the U0S. production of this material,
At plant «v21 pure silver is dissolved in distilled nitric
acid aad the resulting solution is fed to a steam heated
evaporator. The NOx gases from the dissolver are mixed with
air ar.d converted to nitrogen dioxide which is used to
remake nitric acid for the process. The tail gases from the
nitric acid recovery unit are scrubbed with a caustic
solution prior to venting to the atmosphere. The
concentrated mother liquor from the evaporator is sent to a
crystalj.izer and the crystals formed are centrifuged and
wash^rt vith demineralized water. The mother liquor and wash
water from the centrifuge is recycled to the evaporator
after treatment to remove heavy metal impurities. The
silver nitrate crystals from the centrifuge are redissolved
in low pressure steam, recryatallized, recentrifuged,
rewashedr dried and packaged. The mother liquor from the
second crystallizer is sent to another steam heated
evaporator for concentration and recycled to both
crystallj.zers. Simplified process chemical reactions are:
A,g + 2HNO3 = AgNO3 + NO2 + H2O
3Ag * I&HN03 = 3AgNO3 * NO + 2H2O.
The process at plant 421 is shown in Figure 37.
The process used at plant 329 is the same as that described
above witt the exception that extensive use is made of
stream recycling as can be seen from the diagram in Figure
37, There are several differences:
1) The gasaous NOx products from the reactor in plant 329
are entirely reconverted to nitric acid which is recycled.
This eliminates the need for a gas scrubber and the re-
sultant nitrate-bearing scrubber wastes.
2) The raw wastes consist mostly of filter wastes (metal
oxides of copper, lead, etc., precipitated by the addi-
tion of silver oxide). There are also possible wastes
arising from the evaporator barometric condenser. These
150
-------
CAUSTIC g^
SOLUTION ^
NITRIC ACID -J— ^
SILVER •— — HH
WASH fc
WATER ' ^
WATER •*
STEAM •»
rVAPQUATOR
COND/NIATC
WASTE
WASH .^
P
SCRUBBER
t
NITRIC ACID
RECOVERY
SPENT
•*•> SCRUHKR
SOLUTION
9 TAIL GASES
REACTOR
1
EVAPORATOR
1
CRYSTALLIZER
|
1
CENTRIFUGE
1
REDISSOLVER
I
CRYSTALLIZE*
1
CENTRIFUGE
, 1
DRYER
IgJiONOiNMffI
•• 1
CAurric
SOLUTION
u
1W CHEMICAL
1
f
DISCHAROI
TO RBCOVERY
VENT
to BAG FILTER
PTODucr wtio
LANT 421
WATER —
NITRIC
ACID
WATER —
OXYGEN -
SOLIDS
•ILVIR _
0X101
WASH
WATER
WAI Kit -
WASH
WATER
— to| ABSORBER
^
"^j MIXER
-*, *
— H REACTOR
-v 1
| AUXILIARY REACTOR
1
.- ., FIITFR
*
"""^CHEMICAL TREATMENT
^ *
| FILTER
*
| ALUMINA COLUMN
»
^1 EVAPORATOR
^| CRYSTALLIZER
_ »
^^ CENTRIFUGE
*
pij REDISSOLVE TANK
— *^
| FILTER
j
«• — j CRYSTALLIZER
\
V**H CENTRIFUGE
— —^f >iin ,
DRYER
"* — i
TAIL
CASES
fc »OLIO
^ WASTE
^^ TO
^RECOVERY
1 ^ SOLID
| ^ WASTE
PRODUCT
PLANT 329
FIGURE 37
SILVER NITRATE MANUFACTURE
151
-------
are probably the same as those shown for the other silver
nitrate plant.
3) All silver-bearing waste streams are sent to a recovery
unit, where metal values are recovered.
NOTE: The above information on plant 329 was obtained from
the literature (Chemical Engineering, 70, p. 80-88,
August 1963). No additional details are available as
the plant owners have declined to participate in the
study.
Raw Wa s te Lqa d $
The amounts of various waste materials formed by scrubbing
of tail gases, evaporator carryovers, and heavy metals
removed by purification of the mother liquor at plant 121
evaporator
condensate:
scrubber:
chemical
puri f icat ion
W-i ste material
Agt
HN03
other metal ions
kg [»er metric ton
tloor washing:
bag t i 1 to r:
All of the above
go to the silver
Pj^ant Water Use
NaNO2
Ag*
NaN03
Cd
Aq2O
Cu
Fe
Ph
Bi
Sri
Hq
MM
AqNO3
AqNO3
NaNO3
approx.
0.012 (0.024)
21.9 (43.8)
0.0005 (0.001)
29.4 (58.8)
Not given
47
0.0032
1.32
0.013
0.006
0.001
O.OQOfj
0.00OS
(0.0064)
(2.64)
(0.026)
(0.012)
(0.002)
(0.001)
(0.001)
0.000016 (0.000032)
0.0001 (0.0002)
unknown small amount
0.08
(0.16)
raw wastes except the evaporator condensate
recovery system.
152
-------
The principal uses of water in plant U21 are for noncontact
cooling and for process water- Water for the latter is
purified before use. The consumption of water is:
wator consumption liters /met rig ton _of _Eroduct_j^a 1/tonj
process waste discharge 1,470 (353)
noncontact cooling discharge 17,700 (4
A considerably larger amount of water is recirculated
through the crystallizer coolers than the above discharge,
Waste Water Treatment
The evaporator condensate waste stream goes directly to the
plant complex waste treatment facility. The scrubber dis-
charge is intermittent and goes to the silver recovery
plant. The waste flow from the chemical purification system
also goes to silver recovery, as does the floor washings
water. After silver recovery, the discharge goes to the
plant complex treatment facility. This facility consists of
trickling filters in series with activated sludge treatment,,
followed by neutralization, clarification and chlorination.
Greater than 99 percent of the soluble silver is recovered
in the silver recovery treatment and 75 percent of the
remainder is removed in the plant waste treatment.
Effluent
The effluent from the plant complex waste treatment is at pH
7.5 to 8.0. An estimated 0.013/kg of silver/kkg of product
(0.026 Ib/ton) from the silver nitrate production passes
through the silver recovery system to the plant waste
treatment. An estimated 0.003 kg of silver/kkg (0.006
Lb/ton) of this is in turn discharged with the plant
zreatment effluents. The plant effluent contains less than
j.5 mg/1 of suspended solids.
SODIUM FLUORIDE
Tie plants analyzed in this section account for the known
U,,s. production volume of sodium fluoride. The two
pj.-ocesses described are both wet processes but the amounts
and, to a degree, the kinds of waste materials are
dd f f erent.
£l ocess Descriptions
153
-------
At plant 3U3 anhydrous hydrofluoric acid is reacted with
soda ash in a stirred reactor. The hydrofluoric acid fumes
and carbon dioxide gas produced are scrubbed with a soda ash
solution prior to venting to the atmosphere. The scrubber
solution is reused and then discharged to the reactor. The
product solution from the reactor is passed through a series
of surge tanks and fed to a vacuum filter where the product
sodium fluori.de is recovered. The mother liquor is recycled
from this step. The recovered product is mixed with dry
sodium fluoride and fed to a dryer. A process diagram is
given a.n wigure 38. The overall process"reaction is:
2HF * Na2CO3 = 2NaF <• H2O + CO.2.
At plant HQH sodium si licof luoricie is reacted with a
solutior of caustic soda and water in a batch reactor. The
product, a mixture of sodium fluoride, sodium silicate, and
water, is sent to a multi-stage separator, where the sodium
fluoride is separated from the soluble sodium silicate. The
sodium fluoride product is washed, dried and collected in a
dry cyclone for packaging. The wash water from the
separator is recycled -to the reactor. Soluble sodium
silicate and sodium fluoride in an alkaline solution
constitute the by-product waste stream from this process. A
recycle wet scrubber used to remove sodium fluoride dusts
from the vent on the dry collector is blown down to the
silicate vaste effluent. The reaction for the process is:
6NaOH + Na2SiF6 = 6NaF + Na2SiO3 + 3H2O.
A process diagram is shown in Figure 39.
Raw Waste Loads
Process wastes at plant 343 consist of filtrate mother
liquors, washdown waters and product dusts from the
packaging operation. All of these wastes are recycled:
kg per metric ton of product
wa s t e mat e r ia 1 source (Ib/tonj
soda ash and mother liquor 0.42 (0.84)
sodium fluoride
solution
soda ash and washdown not known
sodium fluoride
sodium fluoi:ide dust collection not known
154
-------
SODA
ASH WATER
;\NHYC?OUS HYDROFLUORIC ACID
SCO4 ASH "'I
HOLDING TANK
LIQUOR
SODIUM FLUORIDE
(FROM PRODUCT STREAM)
REACTOR
T
SCRUBBER
VACUUM
CRYSTALLJZER
USED !N
SODIUM I
BIFLUORIDE '
PRODUCTION
ONLY
SURGE TANK
FILTER
SOLIDS
MIXER
STEAM
IU
r
STORAGE
AND
PACKAGING
\
DUST COLLECTOR
I
PRODUCT
FIGURE 38
SODIUM FLUORIDE MANUFACTURE
AT PLANT 343
-155
-------
WATER RECYCLE
WASH
WATER
VENT
WATER
50%
CAUSTIC
SODiUM
SILICOFLUORIDE'
1
BATCH
REACTOR
SEPARATOR
t
DRYER
DRY
COLLECTOR
PRODUCT
WATER
RECYCLE
BATCH SCRUBBER SLOWDOWN
WET
SCRUBBER
•VENT
WASTE
WATER
FIGURE 39
SODIUM FLUORIDE PRODUCTION
FROM CAUSTIC SODA AND SODIUM SILICOFLUORIDE
-------
Process wastes at plant 404 consist of separated silicate
liquors containing soluble sodium fluoride, wet scrubber
blowdown, product wash water and product dusts from the
packaging operation. The product dusts and product wash
water are recycled to the reactor. The other wastes are
combined with wastes from other parts of the complex.
kg per metric ton of product
waste material source jib/ton^
sodium fluoride separator 121.5 (243)
sodium oxide separator 238.5 (477)
silica separator 286.5 (573)
sodium fluoride wet scrubber 18 (36)
sodium fluoride dust collection not known
The considerably higher raw waste load at plant 404 than
plant 343 is due principally to the use of a different raw
material.
Slant _Wa£e£_JJjse
Plant 343 water consumption averages 2,300 of municipal
water/kkg of sodium fluoride product (550 gal/ton). This is
used ;:or boiler feed. The only plant discharge is boiler
blowdown. Steam condensate from the process dryer is
recycled.
Plant 404 has an average intake of 3,860 1/kkg of sodium
fluoride product (925 gal/ton). This water is used for
dilution of the caustic soda, washing the product, and wet
scrubbing. No cooling water or steam is used in the
process, in addition, the process reaction produces 217 of
water/kkg (52 gal/ton). The water consumed for the plant is
as follows:
consumption liters per metric ton of product (qa^/ton)
evaporation 618 (148)
process waste 2,984 (715)
wet scrubber 476 (114)
waste Water Treatment
157
-------
At plant 343 there is no plant process contact water waste,
so no treatment is necessary. The process effluent at plant
404 contains soluble sodium silicate as sodium oxide and
silica along with soluble sodium fluoride. The volume of
the effluent is 2,984 1/kkg of sodium fluoride product (71S
qals/ton) plus the intermittent scrubber blowdown. This
waste r.tredm is combined with other plant wastes and piped
to a solids retention pond where neutralization and settling
take place. This retention pond has an average runoff of
1,128,200 1/kkg (298,080 gals/day) which would be expected
to contain the soluble wastes from the sodium fluoride
production. However, this runoff is variable ranging from 0
to 1,330 gal/min. The solids retention pond does have an
effluent recycle system to the plant complex but because of
insufficient surge capacity the aforementioned runoff occurs
primarily due to precipitation.
At the time of the field study, plant 404 was discharging
the retention pond runoff due to precipitation to the river,
but in mid-1974 the plant installed a surge pond to retain
the runoff and recycle all the effluent from this pond to
the plant complex. This control technique allows the plant
to achieve no discharge of its waste from the sodium
fluoride operation. This control and treatment approach
should be considered feasible only for those plant complexes
where a favorable water balance exists. Also this control
approach would be sensitive to any extended operational
shutdown of the plant complex.
Effluent
Since all process waters are recycled at plant 313 there is
no effluent. The facility has no discharge of process
wastes. The only waters released are used boiler water
which goes to a sewer.
Final effluent at plant 404 from the current discharge of
the wastes from the solids retention pond which are attribu-
table to the sodium fluoride operation would approximate the
following:
waste component kg per metric ton of product (Ibs/ton)
NaF 139.5 (279)
Na20 238.5 (477)
Si02 266.5 (573)
SODIUM SILICOFLUORIDE
158
-------
Data from three plants are given in this section. Their
aggregrate annual production is approximately 48,600 kkg/yr
(53,500 tons). This is nearly 90 percent of current annual
production in the U.S, They are located in the vicinity of
wet process phosphoric acid plants, since this is the source
of one raw material, fluosilicic acid.
Process Description
Two of these plants, 226 and 247, use fluosilicic acid re-
covered from the phosphoric acid production and react it
with sodium chloride in water, precipitating sodium silico-
fluoride. The reaction mixture is settled, che solid pro-
duct separated,, washed, dried, classified and packaged.
Recycle of liquids from separation Fteps is practiced. The
simplified flow diagrams for these two plants, which differ
slightly in details of process, are given in Figures 40 and
41, These show the sources of the process waste streams.
The process reaction is:
2NaCl + H2SiF|> = Na2SiF6 + 2HC1«,
The process practiced at plant 446 differs in that the
source of the fluosilicic acid raw material is an impure
phosphoric acid stream from an on-site phosphoric acid plant
rather than a recovered fluosilicic acid. After refiltering
to remove gypsum, the impure acid stream is treated with
soda ash to precipitate the sodium silicofluoride. This is
separated,. washed, dried, and classified in preparation for
sale, The phosphoric acid after extraction of the sodium
silicofluoride, is returned to the phosphoric acid plant
with essentially all the water that came in with it. " The
gypsum and washings from the filter are returned to the
gypsum disposal system. The process flow diagram is given
in Figure 42. The main process reaction is:
H2SiF6 -5- Na2C03 = Na2SiF6 + H2O + CO2.
Saw_Was:jbe Loads
The raw wastes from these two processes include the
coproducts from the process reactions (HC1 and CO2J , excess
reactants (Nad), impurities and other materials carried in
the raw material streams (phosphates and gypsum), and minor
process additives. The values of these are:
kg per metric__ton_of_prQduct Lib/ton)
process sodium chloride- soda ash-
flli2§ili£i£_acicl phosphoric acid
plant no, 226 247 446
159
-------
FILTRATE WATER
FLUOSILICIC ACID
SODIUM CHLORIDE*
WATER
1
REACTOR h—*H SETTLER U-*J FILTER h—^J KILN
'PRODUCT
WASTE
LIQUOR
TO
TREATMENT
FIGURE 40
SODIUM SILICOFLUORIDE MANUFACTURE AT PLANT 226
-------
WATER —
SOLIDS
/
SODIUM. || IS
CHLORIDE—— >M .„.«-« SETTLER /
(CRY^f LI2ER) h-^H ™» r-+ CENTRIFUGE
11% FLUOS1LIOC ^ vCKYSTALLIZERM CLASSIFIER
ACID ^ j j
f LKXHD UOUID-^1
! RECYCLE COVERS 1
^ _ , 1 „ „_. 5Q
•_. 'tFTTI Ft) -
f oc. i i LJLn
VENT
» SCRUBBER »*!S?ER
SOLIDS ]
f em DRYER n » PRODUC^
LJDS
WASTE
LIQUOR
FIGURE 4i
SODIUM SILICOFLUORIDE MANUFACTURE AT PLANT 247
-------
to
IMPURE
PHOSPHORIC
ACID
SODA ASH
WATER VENT
SCRUBBER
SC
PHOSPHORIC ACD
RETURN TO STORAGE
WATER
SOLIDS
I WASH
WATER
i t
CRYSTALLIZER
U-
£
GASES
*
DRYER
CLASSIFIER
WASTE WATER
•PRODUCT
FIGURE 42
SODIUM SILICOFLUORIDE MANUFACTURE FROM AN IMPURE
PHOSPHORIC ACID STREAM
-------
t.ot.al chloride S^OJilOO; 66J([.U2CJ)
HC1 '450(900} 425(851}
fluoride 30(60) 61(122) 58 ([116)
phosphate (as P) '1.5 f 9) not given
phosphoric acid - - 18,615(37^230)
(as P205J
gypsum - - not given
carbon dioxide - - 234(468)
TDS 500(1000) not given not given
TSS 100 (200) not given not given
surfactant - 0-4( 0,7)
The principal impact of the soda ash process on the raw
waste load is that no acidity is generated in the process
and there are no chloride raw wastes. The large quantity of
phosphoric acid "raw waste" at plant 'Hi6 is, of course, the
phosphoric acid plant product that is returned to that plant
directly after removal of the sodium silicofluoride. The
cypsum rcaw ivaste, which is a left-over from the phosphoric
acid production, also returns to the phosphoric acid plant
with this stream. The CO2 by-product is vented. The
fluoride raw waste, which is generated by the washing of the
sodium silicofluoride, is the only waste that is discharged
xc'.th the process water from this plant.
The suspended solids figure given for plant 226 consists in
pert of sodium chloride crystals. in both plants, the
chloride that is not HC1 is NaCl excess reactant. All of
the raw wastes listed for plants 226 and 247 are due to
process waters, scrubbers arid washdovms.
Pl<»nt_Watgr_...U3g
Water i.s us^d at i-hose plants as a medium for tha process
reaction, for washing the solids from the process, for
scrubbing dryer vent streams, for cooling in some casesf and
for miscellaneous purposes such as sanitary and air
conditioner cooling., In general„ the process waste water
discharges consist of water used for product washing and
scrubbing as well as ivashdown of leaks and spills. The
detc ils of typical amounts of process-related water consumed
at the three plants are as follows:
plant no. 226 247 446
process water and 6,910 £1,655) 16^70(3,950) 10,150-17,750
washdown discharge J2, 340-4,250)
return to phosphoric none none 13,450(3,220)
-------
acid plant with
gypsum
process noncontact - 330(80)
cooling
There is no difference due to the type of process in process
water discharge at these plants that can be seen by
comparing plant 446 with the other two. The lower amount of
process water discharge at plant 226 is attributable in part
to the lack of a vent scrubber at this plant. The average
plant process water discharge of these three is 12,440 1/kkg
(2,980 gal/ton).
Plant Waste Treatment
At plant 226 all of the waste waters are sent to a settling
pond, where presumably the 100 kg of suspended solids /kkg
(200 Ib/ton) settle out, and the liquid overflow is injected
into a deep well.
Treatment at plant 247 consists of neutralization with lime
and settling prior to discharge. This converts the hydro-
chloric acid present in the raw waste stream to calcium
chloride and removes fluosilicates via the reaction:
Na2SiF6 + 3Ca(OH)2 = 3CaF2 + SiO2 + 2NaOH + 2H20
The effect of this treatment is to reduce the fluoride con-
tent of the waste water to the solubility level of calcium
fluoride and r.o precipitate silica.
The plant central treatment system, it may be noted, also
treats wastes from a number of other processes in the com-
plex which manufactures mineral acids in addition to the
f luosilicate.
At plant 446 the process effluent is combined with other,
much larger, wciste flows from the plant complex and neutral-
ized with lime, clarified, cooled and discharged. The aver-
age amount of the effluent from this process is greater than
15,200 1/kkg of product (3,650 gal/ton) and contains, prior
to treatment, the 58 kg of fluoride/kkg (116 Ib/ton) from
product washing plus whatever materials are picked up in the
washdowns, presamably some phosphates, fluorides and soda
ash.
Therefore the typical treatment prior to discharge from
these processes is liming, settling and decantation.
Plant Effluents
164
-------
There is no discharge from plant. 226 since its process waste
waters are disposed of into an on~site well. The liquid
qoinq to the well consists of the raw wastes in the process
water with undieiiolved solids settled out- The solution is
.u:l
-------
VENT
t
CTl
TIN
OR OXYGEN———^
1
SOLIDS
FURNACE
BAG
COLLECTOR
fj- GASES
CYCLONE
SOLIDS
PACKAGING
L—-
PRODUCT
FIGURE 43
DRY PROCESS FOR STANNIC OXIDE PRODUCTION
-------
The dry process has no waterborne wastes and no solid
wastes.
TRQNA PROCESS
Five of the chemicals of this study, borax, boric acid,
bromine, lithium carbonate and potassium chloride, are
manufactured from lake brine at two highly integrated
facilities located at Trona, California under conditions
which are atypical of the rest of this industry. The
recovery processes and raw material are unique to this
location. These processes are carried out in a desert area
immediately adjacent to Searles Lake, a large residual
evaporate salt body filled with saline brines. These brines
are the raw material and are pumped into the processing
facilities where the valuable constituents are separated and
recovered. The residual brines, salts and end liquors,
including added process waters, are returned to the salt
body to maintain the saline brine volume and to permit the
recycle solution mining of the valuable constituents. There
is no "discharge to navigable waters" since the recycle
liquors are actually the medium for producing the raw
material for the processes. Total brine into plant 395 is
about 11,355 cu m/day (3 mgd) with about a quarter being
lost by evaporation. The total recycle back to the salt
bod^ is the same volume, including added process waters.
The salt body is actually two deposits separated by a layer
of muds such that each deposit contains brine of different
typical compositions:
Upper Structure Lower Structure
Kf'l a. 90 3,50
Na2C<3 U. 7 5 6_5Q
NaHCC3 0.15
Na2BU07 1.5 8 j. 5S
Na2B_204 — 0 75
Na2S04 6.75 *6.00
Na2S 0.12 0.30
Na3AsOU 0.05 0 05
Na3POU 0.14 0.10
Nacl 16..10 15.50
H2!O (by difference) 65.46 65.72
w°l 0,008 0.005
Br 0.085 0.071
1 0.003 0.002
F. 0.002 o.OOl
0,018 0.009
167
-------
The percent of total U.S. production of the five chemicals
of interest from the Searles Lake deposit by the Trona
process is estimated as:
borax (merchant) 17%
boric acid 29%
bromine 1%
lithium carbonate 10%
potassium chloride
Below are given descriptions for processes involving each of
the five chemicals. Figures 44 through 47 are process
diagrams for the various portions of the plant 395 facility
at Trona.
Borax and Potassium Chloride (Agricultural Grade]^
Process Description
The only process for recovering potassium chloride, and the
principal process for recovering borax, is a cyclic evapora-
tion-crystallization system in which about 16,350 cu m/day
(4.32 mgd) of saline brine is evaporated to nominal dryness.
The brine, plus recycle mother liquor, is concentrated in
triple-effect steam evaporators to produce a hot concentra-
ted liquor high in potassium chloride and borax. As the
concentration proceeds, large amounts of salt (NaCl) and
burkeite (Na2CO3«Na2SO4) are crystallized and separated.
The former i:5 returned to the salt body while the latter,
which also contains dilithium sodium phosphate, is
transported to another process for separation, ultimately
into soda ash (Na2CO3) , salt cake (Na2SO4) , phosphoric acid
and lithium carbonate.
The hot concentrated liquor is cooled rapidly in vacuum
crystallizers and potassium chloride is filtered from the
resulting slurry. Most of the potassium chloride is dried
and packaged while a portion is refined and/or converted
into potassium sulfate. The cool liquor, depleted in
potassium chloride, is held in a second set of crystallizers
to allow the mora slowly crystallizing borax to separate and
be filtered away from the final mother liquor which is
recycled to the evaporation-concentration step to complete
the process cycle. The borax, combined with borax solids
from the separate carbonation-ref rigeration process, is
purified by recrystallization, dried and packaged.
A second process for recovering borax is a
carbonation-refrlgeration system operating on a separate
brine stream drawn from the salt body at about 4,150 cu
m/day (1.1 mgd). This brine is carbonated with carbon
168
-------
HEAT EXCHANGER
I
TRIPLE EFFECT EVAPORATORS
AMMONIA
COOLING
I
CRYSTALLIZER
1
SALT SEPARATOR
T
VACUUM COOLER j
SOLIDS
TO OTHER
PROCESSES
WATER-
STEAM •
CONE SETTLER
AND FILTER
BORAX
LIQUOR
j CRYSTALLIZER j
I DORR THICKENER j
*—————
FILTER
DISSOLVER j
1
FILTER
1
VACUUM CRYSTALLIZER
1
CENTRIFUGE
DRYER
.KCI TO OTHER
PLANT USE
\
DEPLETED LIQUOR
KCI PRODUCT
DEPLETED LIQUOR
RETURN TO
'BRINE SOURCE
DRYER
CRUDE
"BORAX
FIGURE 44
CRUDE POTASSIUM CHLORIDE AhJD
BORAX MANUFACTURE AT PLANT 395
169
-------
MOIST
CRUDE KCI
STEAM
1
CHLOI
COLLECTION L
TANK p^
1
VACUUM
CRYSTALUZER
1
CONE
SEPARATOR
1
CENTRIFUGE
1
-*• STEAM
DISSOLVER
1
STORAGE
TANK
*INE 1 1 [
1 BROMINE 1
""1 TOWER
BROMINE
VAPOR
BROMIDE
PLANT
PRODUCT BROMIDES
KCI SOLUTION
TO OTHER
PLANT USE
STEAM
DRYER
T
REFINED
KCI PRODUCT
NON-CONTACT
COOLING
; t
CONDENSER
I
DISTILLER
BROMINE PRODUCT
FIGURE 45
REFINED POTASSIUM CHLORIDE AND
BROMINE MANUFACTURE AT PLANT 249
170
-------
CUIFURIC
ACID
FINE
BORAX
REACTION
TANK
I
TANK
CPCNT LIQUOR
TO OTICR
PLANT USE!
WATER VAPOR
t
CRYSTALLIZER
SPENT LIQUOR
WATER•
STEAM-
DRYER
CRUDE
»BORIC ACID
PRODUCT
DISSOLVER
RECRYSTALLIZER
REFINED PRODUCT
FIGURE 46
BORIC ACID MANUFACTURE AT PLANT 314
-------
ro
DISSOLVER
BURKEITE LIQUOR
FILTRATE TO
EVAPORATION - CONCENTRATION
FOR PHOSPHORIC ACID *
PRODUCT
FROTH
FLOTATION
E
FROTH
FROTH
FILTRATION
AND
DRYING
E
DILITHIUM SODIUM PHOSPHATE
LITHIUM SULFATE
LITHIUM
SULFATE
CRYSTALLIZATION
AND
CENTRIFUGATION
T
BURKEITE LIQUOR TO
BOTHER PROCESSES FOR
SODA ASH AND SALT CAKE
j- FILTRATE
LITHIUM
CARBONATE
CRYSTALLIZATION
AND
CENTRIFUGATION
T
SULFURIC ACID
SODA ASH SOLUTION
LITHIUM
CARBONATE
PRODUCT
FIGURE 47
LITHIUM CARBONATE MANUFACTURE AT PLANT 442
-------
dioxide and sodium bicarbonate is crystallized, filtered
from the brine and refined to soda ash. The filtrate is
cooled and borax is crystallized, filtered from the final
brine, and transferred to the borax recrystallization
process (above) to be refined, dried and packaged.
Raw Waste Loads
The only wastes from the basic evaporation-crystallization
process, including the processes for potassium chloride,
borax, soda ash and salt cake, are weak brines made up of
process waters, waste salts and end liquors. These are
returned to the salt body in an amount essentially equal to
the feed rate to the process—about 16,350 cu m/day (4.32
mgd). The recycled liquors enter both the upper and lower
structures of the salt body. In the case of the
carbonation-refrigeration system, the entire brine stream,
.depleted in sodium carbonate and borax, is recycled to the
salt body to continue the solution mining.'
Treatment and Effluent
As the evaporation-crystallization process involves only
recovery of salts from natural saline brines with addition
of only process waters there are no wastes to be treated.
Depleted brines and end liquors are returned to the salt
body. There is no plant discharge to surface waters. The
same considerations apply to the carbonation-refrigeration
process.
Bromine and Refined Potassium Chloride
Process Description
A portion of the potassium chloride is dissolved to make a
hot liquor from which bromine is stripped by using a stream
of chlorine and steam. The bromine is condensed, dl~stilled
and collected as a liquid for sale or other plant use.
The bromine-free liquor is cooled in a vacuum crystallizer
and pure, refined potassium chloride is centrifuged from the
slurry, dried and packaged. The liquor is recycled to
dissolve more crude potassium chloride while a side stream
is used to make potassium sulfate and is ultimately returned
to the principal evaporation-crystallization process.
Raw Waste Loads
173
-------
There are no wastes associated with the production of high
grade potassium chloride and bromine. All liquors are
recycled to this or other processes.
Treatment and
As there are no waste streams generated by this process,
there are no wastes to be treated. No water-borne wast-
effluent is discharged to surface waters.
Boric Acid
Process Description
Boric acid is produced from a liquid-liquid solvent
extraction-evaporative crystallization process operating or.
a separate brine stream drawn from the salt body at about
6rOOO cu m/day (1.58 mgd) . The brine is contacted with an
organic extractant which removes boron, sodium and potassiun
values. The residual brine is recycled directly to the salt
body. The boron, sodium and potassium values are removes
from the organic extractant by washing with aqueous sulfuric
acid. The extractant is recycled while the aqueous solution
of boric acid and sodium and potassium sulfates is
evaporated to nominal dryness in a double effect evaporator
crystallizer. Boric acid is crystallized, centrifuged'
dried and packaged, while a mixture of sodium and potassium
sulfates is crystallized, centrifuged and transferred to
another process for conversion into potassium sulfate.
Raw Waste Loads
The only waste from the process is the brine from which the
boron, sodium and potassium values have been extracted.
This brine is recycled directly to the salt body, in an
amount at least equal to the feed.
Treatment and Effluent
As this process has no effluent to surface waters, no
treatment is required.
Lithium Carbonate
Process Description
Lithium carbonate is recovered from the burkeite which is
separated, as a solid, during the evaporation-
crystallization operations leading to production of
potassium chloride and borax. The burkeite is dissolved in
174
-------
water and the resulting liquor is fed to a froth flotation
system from which a froth containing dilithium sodium
phosphate is removed, filtered and dried. The dried
material is reacted with aqueous sulfuric acid and solid
lithium sulfate is separated. The remaining liquor is
concentrated and sold as crude phosphoric acid. The lithium
sulfate is reacted with soda ash solution and lithium
carbonate is crystallized, centrifuged, dried and packaged.
The filtrate is sent to another process for sodium sulfate
recovery.
Raw Waste Loads
All by-product materials involved in the system are
processed elsewhere in the plant. There are no waterborne
wastes.
Treatment and Effluent
As there is no discharge to surface waters, no treatment is
required.
Miscellaneous Information
There are a large number of vacuum evaporators and
crystallizers used in the Trona operations. Steam is used
in these systems and all water leaving the crystallizers is
in the form of steam.
All brines and process waters used for cooling water,
washings, and other plant uses are returned to the salt body
of the lake. The total complex has no discharge to surface
waters.
The information presented in this section was supplied from
several sources. These are:
(1) Data and process flow charts provided by plant 395.
(2) J.V. Hightower, "The Trona Process", Chemical Engineering,
McGraw-Hill, August, 1951.
(3) J.V. Hightower, "New Carbonation Technique", Chemical
Engineering. McGraw-Hill, May, 1951.
(4) C.R. Havighorst, "AP&CC's New Process Separates Borates
From Ore by Extraction", Chemical Engineering, McGraw-
Hill, November, 1963.
(5) R.N. Shreve, "Chemical Process Industries", McGraw-Hill,
1967, pp. 286-299.
(6) J.E. Teeple, "Industrial Development of Searles Lake Brines",
The Chemical Catalog Co., 1929.
(7) United States Mineral Resources, Prof. Paper 820, pp. 197-
175
-------
216, Supt. Doc., 1973.
(8) Kirk and Othmer, "Encyclopedia of Chemical Technology",
Vol. 3, pp. 631-635; Vol. 16, pp. 380-381, p. 399.
ZINC SULFATE
Zinc sulfate is produced by reaction of sulfuric acid with
various crude zinc starting materials, such as crude zinc
oxide from brass mill fumes, zinc metal residues from
various sources, and zinc carbonate by-product from sodium
hydrosulfite manufacture. In all plants making this
material the same basic steps are followed: reaction of
crude zinc-containing raw material with sulfuric acid,
filtering of solids, treating to precipitate metals,
refiltering of solids, and either evaporation of filtrate
product to dryness or sale of solution grade. Three of the
plants studied in this section are completely separate from
other processes in the facilities they occupy. A fourth
plant is integrated with sodium hydrosulfite manufacture and
so has a complex waste effluent and treatment situation.
From the sulfuric acid reaction step onward it is the same
process as the other three plants.
The four plants whose data are analyzed in this section
account for nearly 90 percent of the total D.S. production.
There is a fifth U.S. plant that is not included, but is
similar in process to the four in this section.
Process Description
Zinc sulfate is synthesized by dissolving zinc metal or zinc
oxide in sulfuric acid. At plants 478 and 479 crude zinc
oxide is reacted vfith sulfuric acid in a leach tank and
decanted. At plant 478, part of the liquor is sent to
granulating kilns to produce granular zinc sulfate and par-t
to a series of treatments to separate manganese as the
dioxide and heavy metals. The filter cakes are solid waste
materials. The mother liquor is concentrated and spray
dried for product. All liquid waste streams are recyled.
Leach tank insolubles are washed, settled out and dried.
The process is shown in Figure US.
At plant 479, the solution resulting from dissolving the
crude zinc oxide is filtered and the filtrate chemically
treated to remove cadmium, lead and copper impurities. The
refiltered solution is evaporated to dryness. The filter
residues are either sold or land stored for future use.
Plant 310 uses zinc residues as the raw material and the
process is generally similar to the above.
176
-------
*
st
WATER
ZINC
OXIDE'
SULFURIC.
ACID
LEACH
TANK
INSOLUBLES
I
WASH
AND
DECANT
I
SETTLE
I
DRY
J^
Tj
KILN
OXIDIZING
AGENT
GEN
AND
FILTER
A
MANGANESE
DIOXIDE
SOLID WASTE
GRANULAR ZINC SULFATE
TREATMENT
CHEMICALS
MIC
H
TREAT»
«FTTLP
-4
LEAD SULFATE
COPPER SPONGE
SOLID WASTE
»INSOLUBLES STOCK- PILE
DRY
SULFATE
PRODUCT
FIGURE 48
ZINC SULFATE MANUFACTURE AT PLANT 478
-------
At plant 202 zinc salt residues recovered from sodium hydro-
sulfite manufacture are first washed with water to remove
sodium salts. The washwaters are sent to the central waste
treatment facility and are really COD-producing wastes
attributable to the hydrosulfite process. The zinc salts
are digested in sulfuric acid and the resulting solution is
filtered to remove insoluble matter and partially
evaporated. The solution is centrifuged to recover the
solid product, which is dried and packaged. The process is
shown in Figure 49.
Raw Waste Loads
The data for plant 310 indicates that no raw waste materials
are produced. The data given for plant 202 include the
sulfite wastes attributable to sodium hydrosulfite
manufacture. Specific amounts of these were not available.
The data for plants 478 and 479 are:
waste material kg per metric ton of product (Ib/ton)
at plant no. 478 479
lead sulfate 34 (67)
lead residues 167-200 (334-400)
cadmium residues <10 (20)
copper sponge 13 (26)
manganese dioxide 1.3 (2.5) none
zinc sulfate (washdowns) not known not given
All of the above except the last material are solid wastes.
The latter liquid raw waste is recycled at plant 478. The
amounts of the solid raw wastes are not affected by startup
or shutdown of operation.
Plant Water Use
The average consumption of water at these three plants
ranges from 2,900 to 9,010 1/kkg of zinc sulfate product
(690 to 2,160 gal/ton). The modes of consumption are:
water liter per metric ton of product (gal/ton)
consumption 3_10 478 479 202
consumed in 3,340 2,250 9,010 not given
product or (800) (540) (2,160)
178
-------
LEAKS AND
SPILLS
WASH I
/WATER f
BY - PRODUCT
CARBONATE
WATFR ~— -
SULFURIC ^___^
ACID —1
WASH mTER |»
RECYCLE \
WASH
TANK
/ WASTE TREATMENT
TANK "
JVENT 1
/GASES t ^!TE
REACTOR
1
FILTER
1 T
EVAPORATOR
1
CENTRIFUGE
1 T
DRYER
to TO
/ GAS COMPLEX
^ INCINERATOR TOATMOn
... ,- — •fc.'tfsf IITION PRfl!illt*T
1W&TER VENT
DUSTS ^ J ^_J
PACKAGING
— i»» SCRUBBER
DRY pfoDUCT WASTE WATER
FIGURE 49
ZINC SULFATE MANUFACTURE AT PLANT 202
179
-------
evaporated
boiler feed 10U (25) 250 (60) not given not given
noncontact none est.UOO none none
cooling (100)
raw material none none none est.20,900
washings (5,000)
There is no process water discharge at any of the first
three plants. Plant 202, which is combined with a sodium
hydrosulfite plant, has a zinc carbonate raw material wash
discharge that is atypical and is attributable to the wastes
of the hydrosulfite process.
Waste Water Treatment
There are not process contact discharges to be treated at
any of the three isolated plants. The solid waste materials
are stockpiled, sold or used as raw materials. The
treatment of the raw material wash water at plant 202
consists of adding soda ash or caustic to precipitate metal
hydroxides. This treated water then passes to the plant
complex treatment.
Effluent
The only discharge at the isolated plants is noncontact
cooling at one plant. There are no process waterborne
discharge wastes, except at plant 202 which is integrated
with a sodium hydrosulfite plant and uses its by-product
zinc carbonate as a raw material. The sulfite and COD
material brought along with this by-product from the
hydrosulfite process is an artifact of the practice of
incomplete washing and drying of the by-product. These wash
wastes should not be attributed to zinc sulfate manufacture.
180
-------
SECTION VI
SELECTION OF POLLUTANT PARAMETERS
INTRODUCTION
The waste water constituents of pollutional significance for
this segment of the inorganic chemicals industry are based
upon those parameters which have been identified in the
effluents from each subcategory of this study. The waste
water constituents are further divided into those that have
been selected as pollutants of significance with the
rationale for their selection, and those that are not deemed
significant with the rationale for their rejection.
The basis for selection of the significant pollutant para-
meters was:
1) toxicity to humans, animals, fish and aquatic organisms;
2) substances causing dissolved oxygen depletion in streams;
3) soluble constituents that result in undesirable tastes and
odors in water supplies;
U) substances that result in eutrophication and stimulate un-
desirable algae growth;
5) substances that produce unsightly conditions in receiving
water; and
6) substances that result in sludge deposits in streams.
SIGNIFICANCE AND RATIONALE FOR SELECTION OF POLLUTION
PARAMETERS
Ammonia
Ammonia is a common product of the decomposition of organic
matter. Dead and decaying animals and plants along with
human and animal body wastes account for much of the ammonia
entering the aquatic ecosystem. Ammonia exists in its non-
ionized form only at higher pH levels and is the most toxic
in this state. The lower the pH, the more ionized ammonia
is formed and its toxicity decreases. Ammonia, in the
presence of dissolved oxygen, is converted to nitrate (NO3)
by nitrifying bacteria. Nitrite (NO2), which is an
intermediate product between ammonia and nitrate, sometimes
occurs in quantity when depressed oxygen conditions permit.
Ammonia can exist in several other chemical comninations
including ammonium chloride and other salts.
181
-------
Nitrates are considered to be among the poisonous
ingredients of mineralized waters, with potassium nitrate
being more poisonous than sodium nitrate. Excess nitrates
cause irritation of the mucous linings of the
gastrointestinal tract and the bladder; the symptoms are
diarrhea and diuresis, and drinking one liter of water
containing 500 ng/1 of nitrate can cause such symptoms.
Infant methemogloblnemia, a disease characterized by certain
specific blood changes and cyanosis, may be caused by high
nitrate concentrations in the water used for preparing
feeding formulae. While it is still impossible to 'state
precise concentration limits, it has been widely recommended
that water containing more than 10 mg/1 of nitrate nitrogen
(NO3-N) should not be used for infants. Nitrates are also
harmful in fermentation processes and can cause disagreeable
tastes in beer. In most natural water the pH range is such
that ammonium ions (NH4+) predominate. In alkaline waters,
however, high concentrations of un-ionized ammonia in
undissociated ammonium hydroxide increase the toxicity of
ammonia solutions. In streams polluted with sewage, up to
one-half of the nitrogen in the sewage may be in the form of
free ammonia, and sewage may carry up to 35 mg/1 of total
nitrogen. It has been shown that at a level of 1.0 mg/1 un-
ionized ammonia, the ability of hemoglobin to combine with
oxygen is impaired and fish may suffocate. Evidence
indicates that ammonia exerts a considerable toxic effect on
all aquatic life within a range of less than 1.0 mg/1 to 25
mg/1, depending on the pH and dissolved oxygen level
present.
Ammonia can add to the problem of eutrophication by
supplying nitrogen through its breakdown products. Some
lakes in warmer climates, and others that are aging quickly
are sometimes limited by the nitrogen available. Any
increase will speed up the plant growth and decay process.
Arsenic
Arsenic is found to a small extent in nature in the
elemental form. It occurs mostly in the form of arsenites
of metals or as pyrites.
Arsenic is normally present in sea water at concentrations
of 2 to 3 mg/1 and tends to be accumulated by oysters and
other shellfish. Concentrations of 100 mg/kg have been
reported in certain shellfish. Arsenic is a cumulative
poison with long-term chronic effects on both aquatic
organisms and on mammalian species and a succession of small
doses may add up to a final lethal dose. It is moderately
182
-------
toxic to plants and highly toxic to animals especiallv as
AsH3.
Arsenic trioxide, which also is exceedingly toxic, was
studied in concentrations of 1.96 to 40 mg/1 and found to be
harmful in that range to fish and other aquatic life. Work
by the Washington Department of Fisheries on pink salmon has
shown that at a level of 5.3 mg/1 of As2O3 for 8 days was
extremely harmful to this species; on mussels, a level of 16
mg/1 was lethal in 3 to 16 days.
Severe human poisoning can result from 100 mg
concentrations, and 130 mg has proved fatal. Arsenic can
accumulate in the body faster than it is excreted and can
build to toxic levels, from small amounts taken periodically
through lung and intestinal walls from the air, water and
food. . . .
Arsenic is a normal constituent of most soils, with
concentrations ranging up to 500 mg/kg. Although very low
concentrations of arsenates may actually stimulate plant
growth, the presence of excessive soluble arsenic in
irrigation waters will reduce the yield of crops, the main
effect appearing to be the destruction of chlorophyll in the
foliage. Plants grown in water containing one mg/1 of
arsenic trioxides showed a blackening of the vascular
bundles in the leaves. Beans and cucumbers are very
sensitive, while turnips, cereals, and grasses are
relatively resistant. Old orchard soils in Washington that
contained H to 12 mg/kg of arsenic trioxide in the topsoil
were found to have become unproductive.
Barium
Barium is a harmful substance encountered in the production
of barium compounds and zinc oxide (wet process). The per-
missible criterion for barium in public waters is 1.0
mg/1 (15) .
Biochemical Oxygen Demand
Biochemical oxygen demand (BOD) is a measure of the oxygen
consuming capabilities of organic matter. The BOD does not
in itself cause direct harm to a water system, but it does
exert an indirect effect by depressing the oxygen content of
the water. Sewage and other organic effluents during their
processes of decomposition exert a BOD, which can have a
catastrophic effect on the ecosystem by depleting the oxygen
supply. Conditions are reached frequently where all of the
oxygen is used and the continuing decay process causes the
183
-------
production of noxious gases such as hydrogen sulfide and
methane. Mater with a high BOD indicates the presence of
decomposing organic matter and subsequent high bacterial
counts that degrade its quality and potential uses.
Dissolved oxygen (DO) is a water quality constituent that,
in appropriate concentrations, is essential not only to keep
organisms living but also to sustain species reproduction,
vigor, and the development of populations. Organisms
undergo stress at reduced DO concentrations that make them
less competitive and able to sustain their species within
the aquatic environment. For example, reduced DO
concentrations have been shown to interfere with fish
population through delayed hatching of eggs, reduced size
and vigor of embryos, production of deformities in young,
interference with food digestion, acceleration of blood
clotting, decreased tolerance to certain toxicants, reduced
food efficiency and growth rate, and reduced maximum
sustained swimming speed. Fish food organisms are likewise
affected adversely in conditions with suppressed DO. Since
all aerobic aquatic organisms need a certain amount of
oxygen, the consequences of total lack of dissolved oxygen
due to a high BOD can kill all inhabitants of the affected
area.
If a high BOD is present, the quality of the water is
usually visually degraded by the presence of decomposing
materials and algae blooms due to the uptake of degraded
materials that form the foodstuffs of the algal populations.
Chemical Oxygen Demand (COD)
Certain waste water components are subject to aerobic bio-
chemical degradation in the receiving stream. The chemical
oxygen demand is a gross measurement of organic and
inorganic material as well as other oxygen-demanding
material which could be detrimental to the oxygen content of
the receiving water.
Chromium
Chromium, in its various valence states, is hazardous to
man. It can produce lung tumors when inhaled and induces
skin sensitizations. Large doses of chromates have
corrosive effects on the intestinal tract and can cause
inflammation of the kidneys. Levels of chromate ions that
have no effect on man appear to be so low as to prohibit
determination to date.
184
-------
The toxicity of chromium salts toward aquatic life varies
widely with the species, temperature, pfl, valence of the
chromium, and synergistic or antagonistic effects,
especially that of hardness. Fish are relatively tolerant
of chromium salts, but fish food organisms and other lower
forms of aquatic life are extremely sensitive. Chromium
also inhibits the growth of algae.
In some agricultural crops, chromium can cause reduced
growth or death of the crop. Adverse effects of low
concentrations of chromium on corn, tobacco and sugar beets
have been documented.
Copper
Copper salts occur in natural surface waters only in trace
amounts, up to about 0.05 mg/1, so that their presence
generally is the result of pollution. This is attributable
to the corrosive action of the water on copper and brass
tubing, to industrial effluents, and frequently to the use
of copper compounds for the control of undesirable plankton
organisms.
Copper is not considered to be a cumulative systemic poison
for humans, but it can cause symptoms of gastroenteritis,
with nausea and intestinal irritations, at relatively low
dosages. The limiting factor in domestic water supplies is
taste. Threshold concentrations for taste have been
generally reported in the range of 1.0-2.0 mg/1 of copper,
while as much as 5-7.5 mg/1 makes the water completely
unpalatable.
The toxicity of copper to aquatic organisms varies
significantly, not only with the species, but also with the
physical and chemical characteristics of the water,
including temperature, hardness, turbidity, and carbon
dioxide content. In hard water, the toxicity of copper
salts is reduced by the precipitation of copper carbonate or
other insoluble compounds. The sulfates of copper and zinc,
and of copper and cadmium are synergistic in their toxic
effect on fish.
Copper concentrations less than 1 mg/1 have been reported to
be toxic, particularly in soft water, to many kinds of fish,
crustaceans, mollusks, insects, phytoplankton and
zooplankton. Concentrations of copper, for example, are
detrimental to some oysters above .1 ppm. Oysters cultured
in sea water containing 0.13-0.5 ppm of copper deposited the
metal in their bodies and became unfit as a food substance.
185
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Cyanide
Cyanides in water derive their toxicity primarily from
undissolved hydrogen cyanide (HCN) rather than from the
cyanide ion (CN-). HCN dissociates in water into H+ and CW-
in a pH-dependent reaction. At a pH of 7 or below, less
than 1 percent of the cyanide is present as CN-; at a pH of
8, 6.7 percent; at a pH of 9, 42 percent; and at a pK of 10,
87 percent of the cyanide is dissociated. The toxicity of
cyanides is also increased by increases in temperature and
reductions in oxygen tensions. A temperature rise of 10°C
produced a two- to threefold increase in the rate of the
lethal action of cyanide.
Cyanide has been shown to be poisonous to humans, and
amounts over 18 ppm can have adverse effects. A single dose
of 6, about 50-60 mg, is reported to be fatal.
Trout and other aquatic organisms are extremely sensitive to
cyanide. Amounts as small as .1 part per million can kill
them. Certain metals, such as nickel, may complex with
cyanide to reduce lethality especially at higher pH values',
but zinc and cadmium cyanide complexes are exceedingly
toxic. ^ J
When fish are poisoned by cyanide, the gills become
considerably brighter in color than those of normal fish
owing to the inhibition by cyanide of the oxidase
responsible for oxygen transfer from the blood to the
tissues.
Fluorides
As the most reactive non-metal, fluorine is never found free
in nature but as a constituent of fluorite or fluorspar,
calcium fluoride, in sedimentary rocks and also of cryolite
sodium aluminum fluoride, in igneous rocks. Owing to their
origin only in certain types of rocks and only in a"few
regions, fluorides in high concentrations are not a common
constituent of natural surface waters, but they may occur in
detrimental concentrations in ground waters.
Fluorides are used as insecticides, for disinfecting brewery
apparatus, as a flux in the manufacture of steel, for
preserving wood and mucilages, for the manufacture of glass
and enamels, in chemical industries, for water treatment.
and for other uses.
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Fluorides in sufficient quantity are toxic to humans, with
doses of 250 to 450 mg giving severe symptoms or causing
death.
There are numerous articles describing the effects of
fluoride-bearing waters on dental enamel of children; these
studies lead to the generalization that water containing
less than 0.9 to 1.0 mg/1 of fluoride will seldom cause
mottled enamel in children, and for adults, concentrations
less than 3 or 4 mg/1 are not likely to cause endemic
cumulative fluorosis and skeletal effects. Abundant
literature is also available describing the advantages of
maintaining 0.8 to 1.5 mg/1 of fluoride ion in drinking
water to aid in the reduction of dental decay, especially
among children.
Chronic fluoride poisoning of livestock has been observed in
areas where water contained 10 to ' 15 mg/1 fluoride.
Concentrations of 30-50 mg/1 of fluoride in the total ration
of dairy cows is considered the upper safe limit. Fluoride
from waters apparently does not accumulate in soft tissue to
a significant degree and it is transferred to a very small
extent into the milk and to a somewhat greater degree into
eggs. Data for fresh water indicate that fluorides are
toxic to fish at concentrations higher than 1.5 mg/1.
Hydrogen Sulfide
Hydrogen sulfide may be found in significant quantities from
the manufacture of barium carbonate and sodium hydrosulfide.
This parameter is of concern because of its deletrious
effects to aquatic organisms and animals as well as the
taste and odor problems created with public water supplies.
Complete absence as a desirable criterion are the FWPCA's
Committee on Water Quality Criteria recotrunendations for
public waters(13).
Manganese
Manganese may be present in significant amounts in the waste
water from the manufacture of carbon dioxide from the
ammonia by-product process, manganese sulfate, and potassium
permanganate. A permissible criterion of 0.05 mg/1 has been
proposed for public waters(15).
Nickel
Elemental nickel seldom occurs in nature, but nickel
compounds are found in many ores and minerals. As a pure
metal it is not a problem in water pollution because it is
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not affected by, or soluble in, water. Many nickel salts,
however, are highly soluble in water.
Nickel is extremely toxic to citrus plants. It is found in
many soils in California, generally in insoluble formf but
excessive acidification of such soil may render it soluble,
causing severe injury to or the dedth of plants. Many
experiments with plants in solution cultures have shown that
nickel at 0.5 to 1.0 mq/1 is inhibitory to growth.
Nickel salts can k I] ;, fish dn. v«>ry low concentrations. Data
for the fathead minnuw <*how death occurring in the raisge ot
5-153 mg, depending on the alkalinity of the u*ater.
Nickel is present in coastal and open ocean concentrations
in the range of 0.1 - 6.0 ug/1, although the roost common
values are 2-3 ug/1. Marine animals contain up to 400
ug/1, and marine plants contain up to 3,000 ug/1. The
lethal limit of nickel to some marine fish has been reported
as low as 0.8 ppm. Concentrations of 13.1 mg/1 have been
reported to cause a 50 percent reduction of the
photosynthetic activity in the giant kelp (Macrocystis
pyrifera) in 96 hours, and a low concentration was found to
kill oyster eggs.
lodate
lodate is harmful substance(11) which may be found in
significant amounts from the manufacture of potassium
iodide.
Iron
Iron is considered to be a highly objectional constituent in
public water supplies (16), the permissible criterion has
been set at 0.3 mg/1(15). iron is found in significant
quantities from the manufacture of iron salts, chrome
pigments and lithium carbonate.
Lead
Lead may be present in significant amounts in the waste
water from the manufacture of chrome pigments and lead
oxide. Because lead and its compounds are highly
objectionable (11), a permissible criterion of 0.05 mg/1 and
complete absence was recommended by the FWPCA(13).
£H, Acidity and Alkalinity
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Acidity and alkalinity are reciprocal terms. Acidity is
produced by substances that yield hydrogen ions upon
hydrolysis and alkalinity is produced by substances that
yield hydroxyl ions. The terms "total acidity" and "total
alkalinity" are often used to express the buffering capacity
of a solution. Acidity in natural waters is caused by
carbon dioxide, mineral acids, weakly dissociated acids, and
the salts of strong acids and weak bases. Alkalinity is
caused by strong bases and the salts of strong alkalies and
weak acids.
The term pH is a logarithmic expression of the concentration
of hydrogen ions. At a pH of 7, the hydrogen and hydroxyl
ion concentrations are essentially equal and the water is
neutral. Lower pH values indicate acidity while higher
values indicate alkalinity. The relationship between pH and
acidity or alkalinity is not necessarily linear or direct.
Waters with a pH below 6.0 are corrosive to water works
structures, distribution lines, and household plumbing
fixtures and can thus add such constituents to drinking
water as iron, copper, zinc, cadmium and lead. The hydrogen
ion concentration can affect the "taste" of the water. At a
low pH water tastes "sour". The bactericidal effect of
chlorine is weakened as the pH increases, and it is
advantageous to keep the pH close to 7. This is very
significant for providing safe drinking water.
Extremes of pH or rapid pH changes can exert stress
conditions or kill aquatic life outright. Dead fish,
associated algal blooms, and foul stenches are aesthetic
liabilities of any waterway. Even moderate changes from
"acceptable" criteria limits of pH are deleterious to some
species. The relative toxicity to aquatic life of many
materials is increased by changes in the water pH.
Metalocyanide complexes can increase a thousand-fold in
toxicity with a drop of 1.5 pH units. The availability of
many nutrient substances varies with the alkalinity and
acidity. Ammonia is more lethal with a higher pH.
The lacrimal fluid of the human eye has a PH of
approximately 7.0 and a deviation of 0.1 pH unit from the
norm may result in eye irritation for the swimmer.
Appreciable irritation will cause severe pain.
Selenium
Selenium may be present in significant amounts in the waste-
waters from the manufacture of copper sulfate by the copper
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refinery waste process. The permissible criterion for sele-
nium is 0.01 mg/1 in public water supplies(15) .
Silver
Silver may be present in significant quantities in tne
wastewater from the manufacture of silver salts. The
reconmended permissible criterion for silver in public water
supplies is 0.05 mg/1 (16).
Total Suspended Solidg
Suspended solids include both organic and inorganic
materials. The inorganic components include sand, silt, and
clay. The organic fraction includes such materials as
grease, oil, tar, animal and vegetable fats, various fibers,
sawdust, hair, and various materials from sewers. These
solids may settle out rapidly and bottom deposits are often
a mixture of both organic and inorganic solids. They
adversely affect fisheries by covering the bottom of the
stream or lake with a blanket of material that destroys the
fish-food bottom fauna or the spawning ground of fish.
Deposits containing organic materials may deplete bottom
oxygen supplies and produce hydrogen sulfide, carbon
dioxide, methane, and other noxious gases.
In raw water sources for domestic use. State and regional
agencies generally specify that suspended solids in streams
shall not be present in sufficient concentration to be
objectionable or to interfere with normal treatment
processes. Suspended solids in water may interfere with
many industrial processes, and cause foaming in boilers, or
encrustations on equipment exposed to water, especially as
the temperature rises. Suspended solids are undesirable in
water for textile industries; paper and pulp; beverages;
dairy products; laundries; dyeing; photography; cooling
systems, and power plants. Suspended particles also serve
as a transport mechanism for pesticides and other substances
which are readily sorbed into or onto clay particles.
Solids may be suspended in water for a time, and then settle
to the bed of the stream or lake. These settleable solids
discharged with man's wastes may be inert, slowly
biodegradable materials, or rapidly decomposable substances.
While in suspension, they increase the turbidity of the
water, reduce light penetration and impair the
photosynthetic activity of aquatic plants.
Solids in suspension are aesthetically displeasing. When
they settle to form sludge deposits on the stream or lake
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bed, they are often much more damaging to the life in water,
and they retain the capacity to displease the senses.
Solids, when transformed to sludge deposits, may do a
variety of damaging things, including blanketing the stream
or lake bed and thereby destroying the living spaces for
those benthic organisms that would otherwise occupy the
habitat. When of an organic and therefore decomposable
nature, solids use a portion or all of the dissolved oxygen
available in the area. Organic materials also serve as a
seemingly inexhaustible food source for sludgeworms and
associated organisms.
Turbidity is principally a measure of the light absorbing
properties of suspended solids. It is frequently used as a
substitute method of quickly estimating the total suspended
solids when the concentration is relatively low.
Sulfide
Sulfides may be present in significant amounts in the waste-
waters from the manufacture of barium carbonate and sodium
hydrosulfide. Concentrations in the range of 1.0 to 25.0
rag/1 of sulfides may be lethal in 1 to 3 days to a variety
of fresh water fish(14).
Sulfite
Sulfites may be present in significant amounts in the waste-
waters from the manufacture of sodium hydrosulfite and
bisulfite. The sulfite is an intermediate oxidative state
of sulphur, between sulfides and sulfates and exerts a
chemical oxygen demand on the receiving stream and,
therefore, will show up in a COD test.
Tin
Tin may be present in significant amounts in the waste
waters from the manufacture of stannic oxide by both the wet
and dry processes. Tin has been found to be toxic to fish
and aquatic organisms in certain concentrations(14).
Zinc
Occurring abundantly in rocks and ores, zinc is readily
refined into a stable pure metal and is used extensively for
galvanizing, in alloys, for electrical purposes, in printing
plates, for dye-manufacture and for dyeing processes, and
for many other industrial purposes. Zinc salts are used in
paint pigments, cosmetics, Pharmaceuticals, dyes,
insecticides, and other products too numerous to list
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herein. Many of these salts (e.g., zinc chloride and zinc
sulfate) are highly soluble in water; hence, it is to be
expected that zinc might occur in many industrial wastes
On the other hand, some zinc salts (zinc carbonate, zinc
oxide, zinc sulfide) are insoluble in water and consequently
it is to be expected that some zinc will precipitate and be
removed readily in most natural waters.
In zinc-mining areas, zinc lias been found in waters in
concentrations as high as 50 mg/1 and in effluents from
metal-plating works and small-arms ammunition plants it may
occur in significant concentrations. in most surface and
ground waters, it is present only in trace amounts. There
is some evidence that zinc ions are adsorbed strongly and
permanently on silt, resulting in inactivation of the zinc.
Concentrations of zinc in excess of 5 mg/1 in raw water used
for drinking water supplies cause an undesirable taste which
persists through conventional treatment. Zinc can have an
adverse effect on man and animals at high concentrations.
In soft water, concentrations of zinc ranging from 0.1 to
1.0 mg/1 have been reported to be lethal to fish. zinc is
thought to exert its toxic action by forming insoluble
compounds with the mucous that covers the gills, by damage
to the gill epithelium, or possibly by acting as an internal
poison. The sensitivity of fish to zinc varies with
species, age and condition, as well as with the physical and
chemical characteristics of the water. Some acclimatization
to the presence of zinc is possible. it has also been
observed that the effects of zinc poisoning may not become
apparent immediately, so that fish removed from zinc-
contaminated to zinc-free water (after 4-6 hours of exposure
to zinc) may die US hours later. The presence of copper in
water may increase the toxicity of zinc to aquatic
organisms, but the presence of calcium or hardness may
decrease the relative toxicity.
Observed values for the distribution of zinc in ocean waters
vary widely. The major concern with zinc compounds in
marine waters is not one of acute toxicity, but rather of
the long-term, sub-lethal effects of the metallic compounds
and complexes. From an acute toxicity point of view
invertebrate marine animals seem to be the most sensitive
organisms tested. The growth of the sea urchin, for
example, has been retarded by as little as 30 mg/1 of zinc.
Zinc sulfate has also been found to be lethal to many
plants, and it could impair agricultural uses.
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SIGNIFICANCE AND RATIONALE FOR REJECTION OF POLLUTION
PARAMETERS
A number of pollution parameters besides those selected were
considered, but were rejected for one or several of the
following reasons:
1) insufficient data on degradation of water quality;
2) not usually present in quantities sufficient to cause
water quality degradation;
3) treatment methods do not currently exist to "practicably"
reduce the parameter; and
4) simultaneous reduction is achieved with another parameter
which is limited.
Aluminum
Aluminum may be present in significant amounts in the waste-
water from the manufacture of aluminum chemicals, ore
processing or smelter wastes. Soluble aluminum in public
water supplies is not considered a health problem and
therefore was not included in the Public Health Service
Drinking Water Standards (12) .
Bromide
Bromides could be present in the waste waters of bromine
production but are not present in quantities sufficient to
cause water quality degradation.
Calcium
Although calcium does exist in quantities in the waste
waters of a number of inorganic processes, there is no
treatment to practicably reduce it.
Carbonate
There is insufficient data for dissolved carbonate to
consider it a harmful pollutant.
Chloride
Although chloride is present in sufficient quantities in
process waste waters, there is no treatment to practicably
reduce it.
Iodide
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Iodides could be present in the waste water from iodine and
potassium iodide production but not in quantities sufficient
to cause water quality degradation.
Lithium
There is insufficient data for dissolved lithium to consider
it a harmful pollutant,,
Magnesium
There is insufficient data for dissolved magnesium to
consider it a harmful pollutant.
Mercury
Although mercury is a hazardous pollutant, it was not found
to be present in quantities sufficient to cause water
quality degradation.
Phosphates
Phosphates, reported as total phosphorus (PJ, contribute to
eutrophication in receiving bodies of water. However, they
were not found in quantities sufficient to cause water
quality degradation.
Potassium
Although potassium does exist in quantity in the waste
waters of a number of inorganic processes, there is no
treatment to practicably reduce it.
Silicates
Silicate may be present in the waste waters from the
manufacture of sodium silieofluoride, but it is
' 'multaneously reduced with another parameter which is
: -ited.
*"ifchough sodium does exist in quantity in the waste waters
c a number of inorganic processes, there is no treatment to
i. cticably reduce it.
& jiids. Dissolved
T e total dissolved solids is a gross measure of the amount
c soluble pollutants in the waste water. It is an
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important parameter in drinking water supplies and water
used for irrigation. A total dissolved solids content of
less than 500 mg/1 is considered desirable. From the
standpoint of quantity discharged, IDS could have been
considered a harmful characteristic. However, energy
requirements, especially for evaporation, and solid waste
disposal costs are usually so hign as tc preclude limiting
dissolved solids at this time.
Sulfate
Although sulfate does exist in quantity in the waste waters
of a number of inorganic processes, there is no treatment to
practicably reduce it.
Temperature
Temperature is a sensitive indicator of unusual thermal
loads where waste heat is involved in the process. Excess
thermal load, even in noncontact cooling water in the
inorganic chemical industry, has not been and is not
expected to be a significant problem.
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SECTION VII
CONTROL AND TREATMENT TECHNOLOGY
INTRODUCTION
The majority of waterborne wastes from the inorganic
chemicals industry are dissolved solids mainly as low-valued
materials such as sodium chloride, calcium chloride, and
sodium sulfate but often containing smaller quantities of
hazardous or toxic substances. Control and treatment
technology for dissolved solids is well-known; in fact, the
handling, isolation and recovery of dissolved solids is
basic to inorganic chemicals manufacture.
The other component of the inorganic chemicals industry's
waterborne waste load, suspended solids, is usually smaller,
simpler and more economical to deal with than dissolved
solids.
Although the control and ^treatment practices for the water-
borne wastes from the manufacturing of the inorganic
chemicals covered in this report are similar to those
encountered in the major inorganic chemicals effluent
guidelines study (Contract No. 68-01-1513), there are some
differences or trends that are worthy of mention:
1) Overall waste loads are smaller for the chemicals of
this study as compared to the wastes of the major
inorganic products. This follows frojt the fact that the
chemicals of this study are produced in smaller volume.
Below are listed typical waterborne raw waste loads for
some chemicals studied:
chemical
lithium
carbonate
sodium sili-
cofluoride
chrome
pigments**
manganese
sulfate
iron blues
raw waste***
production product
metric tons/yr kg/kkg
(tons/year) (tons/ton!
12,250(13,500) est.7.3(11.6)
54,800(60,418) 0.5(1.0)
42,000(46,261) 0.28(0.55)
33,500(36,971)
4,890(5,387)
0. 22 (0. 44)
0.95(1.9)
raw waste
metric tons/yr
(tons/year)
179,000(197,000)
54,000(60,000)
22,500(25,000)
14,600(16,000)
9,000(10,000)
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barium 54,900(60,513) 0.05(0.1) 5,400(6,000)
carbonate
calcium 164,900(181,765) 0.01(0.02) 3,200(3,600)
carbonate
potassium 11,000(12,144) 0.08(0.15) 1,600(1,800)
permanganate
sodium 22,800(25,113) 0.014(0.028) 630(700)
thiosulfate
sodium 27,200(29,988) 0.010(0.019) 510(570)
hydrosulfide
tin oxide 415(458) 0.6(1.2) 490(540)
All production figures except lithium carbonate were taken
from: U.S. Bureau of the Census, Current Industrials
Reports, Series M28A(71)-14, Inorganic Chemicals 1971,
Washington, D.C., 1972.
*Over 80% of the raw waste is land stored ore residue.
Non-ore residue wastes are 33,000 tons/yr (2.4 tons/ton
product) .
**Included pigments are zinc yellow, chrome yellow, molyb-
date chrome orange, chrome green, and chrome oxide green.
***Typical raw waste loads were estimated from information
supplied from manufacturers of the given chemicals.
2) In some instances, several completely different
manufacturing processes, wastes, and wastes treatments
were encountered for a given chemical covered in this
study.
3) Municipal sewers are used with greater frequency for
disposal of waterborne wastes from the manufacture of
these chemicals than the major inorganic chemicals.
4) Since these chemicals are of lower production volume,
they may be made in a large complex and have their
waterborne wastes consolidated with those of the entire
complex for treatment. This consolidation makes both
identification of these wastes and evaluation of the
effects of treatment performance more difficult than is
the case for isolated plants.
5) The wastes for these chemicals are more complex than
those for the major inorganic chemicals which were
mainly from production of low-cost, high-volume
chemicals consisting of sodium, calcium, chlorides and
sulfates. The wastes from production of these chemicals
include copper, zinc, silver, lead, chromium, tin,
manganese, barium, lithium, bromine, iodine and other
expensive components as well as the full gamut of low-
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value wastes together with toxic materials such as
cyanides and arsenic compounds.
6) Since both the products and the waterborne wastes often
have high recovery value and/or toxicity, control and
treatment technology is more widely applied and more
complex than was the case for most of the major
inorganic chemicals.
GENERAL METHODS FOR CONTROL AND TREATMENT PRACTICES
Waste abatement for the inorganic chemicals industry is
accomplished by a variety of methods. These methods may be
divided into in-plant control and containment practices and
water waste treatment operations. In many cases the control
and containment practices are more important than subsequent
treatments as far as feasibility and costs of waste
abatement are concerned,
In-Plant Control and Containment Practices
Control of the wastes include in-process abatement measures,
monitoring techniques, safety practices, housekeeping, con-
tainment provisions and segregation practices.
Raw Materials
Purity of the raw materials used in the manufacturing
process influences the waste load. Inert or unusable
components entering the process are discharged as waste.
Economics and availability, however, necessitate use of
impure ores and technical grade reactants.
Control of these impurities can be exercised in many
instances. Ores can be washed, purified, separated,
beneficiated or otherwise treated to reduce the waste coming
into the process. An important facet of this approach is
that this treatment can often be done at the mining site
where such operations may be contained or handled on the
premises without waste water effluents.
Reactions
Except in rare cases, chemical reaction is involved in the
manufacture of inorganic chemicals. Sometimes the reactants
are stoichiometrically balanced, but more often than not an
excess of one or more of the reactants is used. The
purposes of the excess vary but include:
1) certainty that the more expensive reactants are completely
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utilized;
the reactio« ^ the desired
reactant be
shortening reaction time.
Excess reactants must be recovered for recycle or else they
become part of the waste load. Y
Separations, Purifications and Recoveries
Products' by-products, impurities,
, ,
^ r materials Present need to be separated,
are carried out by
di"erences « boiling points, freezing points?
2nd reactivity to separate produces froi
Sines: ^ ^^ ™* *^*^ of theae
1) the fraction of product that is lost as waste or has to be
recycled;
2) the purity of the product;
3) control of air pollutants;
<») the recovery and/or disposition of by-products and wastes.
The more complete the separation into recovered product, raw
materials that can be recycled, and wastes, the smaller the
waste load from the process. The degree of separation
actually achieved in the process depends on physical,
chemical and economic considerations.
Cooling water and steam are used in large quantities in the
separation and purification steps. Indirect heating and
cooling may, in many instances, virtually eliminate
waterborne wastes.
Segregation
Probably the most important waste control technique,
particularly for subsequent treatment feasibility and
economics, is segregation.
Incoming pure water picks up contaminants from various uses
and sources including:
1) contact cooling water;
2) process water;
3) washings, leaks and spills;
U) incoming water treatments;
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5) cooling tower blowdowns; and
6) boiler blowdowns.
If wastes from these sources are segregated logically, their
treatment and disposal may sometimes be eliminated entirely
through use in other processes or recycle. in many
instances, the treatment costs, complexity and energy
requirements may be significantly reduced. In general,
plant effluents can be segregated into:
1) Non-contaminated cooling water. Except for leaks, non-
contact water has no waste pickup. It is usually high
volume.
2) Process water. Usually contaminated but often small
volume.
3) Auxiliary streams. Ion exchange regenerants, cooling
tower blowdowns, boiler blowdowns, low volume but often
contaminated.
Although situations vary, the basic segregation principle is
donft mix large uncontaminated cooling water streams with
process and auxiliary streams prior to full treatment and/or
disposal. Aside from economic and energy considerations,
the removal limits of dissolved and suspended pollutants by
treatment are usually influenced by concentration and time
factors, as illustrated by the following examples:
1) It is much more feasible to remove suspended pollutants
in a small volume process stream down to 10 mg/liter and
then dilute 100 to 1 in the overall plant discharge to
0.1 ing/ liter final pollutant concentration than it is
to achieve 0.1 mg/liter suspended pollutant
concentration by treatment of the entire system.
2) Solubility limits are commonly employed to remove
pollutants. For example, lead, mercury, copper and
other heavy metals are removed by precipitation as
relatively insoluble sulfides or hydroxides, fluorides
as calcium fluoride and chromates as lead salts. The
removal level is directly proportional to involved waste
water volume. As an example, removal of soluble
fluoride from a 454 kg quantity of leaks and spills by
lime precipitation would produce calcium fluoride^
mostly insoluble but still soluble to approximately 20
mg/1. Dilution after treatment of 1000 to 1 in the
final plant effluent gives 0.02 mg/1 soluble calcium
fluoride. Similar dilution followed by treatment of the
entire effluent gives 20 mg/1 soluble calcium fluoride.
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3) Tine, as well as concentration, can be important for
such treatment operations as settling of suspended
solids and air oxidations. Since settling time for
suspended solids is largely a matter of particle
characteristics, settling ponds tanks and vessels are
sized on waste water volume. Small segregated waste
water volumes require small ponds or vessels. Large
diluted waste water volumes require large ponds or
vessels (and large land areas). Air oxidations are
slow, relatively inefficient operations. Oxidation
efficiency increa&es with residence time. Small
segregated waste water volumes make long residence
treatment times feasible.
Monitoring Techniques
Since the chemical process industry is among the leaders in
instrumentation practices and application of analytical
techniques to process monitoring and control, there is
rarely any problem in finding technology applicable to waste
water analysis. The relative degree of acidity or
alkalinity are detected by pH meters, often installed for
continuous monitoring and control.
Dissolved solids may be estimated by conductivity
measurements, suspended solids from turbidity, and specific
ions by wet chemistry and colorimetric measurements. Flow
meters of numerous varieties are available for measuring
flow rates.
Monitoring and control of toxic materials such as chromates,
mercury, arsenic and cyanides is often so critical that
batch techniques are used. Each batch is analyzed before
dumping. This approach provides absolute control of all
wastes passing through the system.
Housekeeping and Containment
Containment and disposal requirements may be divided into
several categories:
1) minor product spills and leaks;
2) major product spills and leaks; and
3) upsets and disposal failures.
(a) Minor Spills and Leaks
There are minor spills and leaks in all industrial inorganic
chemical manufacturing operations. For example, pump seals
leak, hoses drip, washdowns of equipment, pipes and
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equipment leak, valves drip, tank leaks occur, solids spill
and so on. These are not going to be eliminated. They can
only be minimized and contained.
Reduction techniques are mainly good housekeeping and atten-
tion to sound engineering and maintenance practices. Pump
seals or type of pumps are changed. Valves are selected for
minimizing drips. Pipe and equipment leaks are minimized by
selection of corrosion-resistant materials.
Containment techniques include drip pans under pumps,
valves, critical small tanks or equipment, and known leak
and drip areas such as loading or unloading stations.
Solids can be cleaned up or washed down. All of these minor
leaks and spills can then go to a containment system, catch
basin, sump pump, or other area that collects and isolates
all of them from other water systems. They should go from
this system to suitable treatment facilities.
(b) Major Spills and Leaks
These are catastrophic occurrences with major loss of
product: tank and pipe ruptures, open valves, explosions,
fires, and earthquakes.
No one can predict, plan for, or totally avoid these happen-
ings; but they are extremely rare. Probably the most common
of these rare occurrences is tank or valve failures. These
can be handled by adequate dikes able to contain the tank
volume. All acid, caustic or harmful material tanks should
be diked to provide this protection. Other special
precautions may be needed for flammable or explosive
substances.
(c) Upsets and Disposal Failures
In many processes there are short term upsets. These may
occur during startup, shutdown or during normal operation
These upsets represent a very small portion of overall
production but they nevertheless contribute to waste loads
Hopefully, the upset products may be treated, separated and
largely recycled. In the event that this cannot be done
they must be disposed of. Disposal failures require
emergency tanks and/or ponds cr seme other expediency for
temporary holding or disposition.
Waterborne Waste Treatment Operations
After the control practices discussed in the previous
section have been utilized, treatment is usually required
203
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for the contaminated streams. In general, these streams nay
be divided into three categories: cooling water, process
water, and ancillary water.
Cooling water, either once-through or recycled by means of a
cooling tower, should be relatively free of wastes. Any
contaminants present would come from leaks or recycle
buildups (cooling tower) which are handled as ancillary
water blowdowns. in either event, cooling waste
contributions are small and treatment should not normally be
needed.
Process and ancillary waterborne wastes usually require
treatment. The type, degree and costs involved will depend
upon specific circumstances unique for each chemical.
Suspended Solids Removal
Suspended solids occur as part of the waterborne waste load,
both from the process and as a result of air and water waste
treatments.
Many of these suspended materials are hazardous or toxic and
need to be removed to levels of 1 mg/liter or less; others
are relatively inert. In either event, most of the
suspended solids removed prior to waste water disposal
eventually wind up as land-disposed solid waste.
(a) Settling Ponds
Settling ponds are the major mechanism used for reducing the
suspended solids content of water waste streams coming from
the plant. Their performance depends primarily on the
settling characteristics of the solids suspended, the flow
rate through the pond and the pond size. Settling ponds can
be used over a wide range of suspended solids levels. Often
a series of ponds is used, with the first ponds collecting
the heavy load of easily settleable material and the
following ones providing final polishing to reach a desired
final suspended solids level. Sludge removal and disposal
from the settling ponds is often a major solid waste
problem. Rarely is there any suspended solids treatment
after the final settling pond. In most cases the suspended
solids level from the final pond ranges from 10 to 30 mg/1,
but for some the values range up to 100 mg/1.
(b) Clarifiers and Thickeners
An alternate method of removing suspended solids is through
the use of clarifiers and thickeners. Commercially, these
204
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units are listed as clarifiers or thickeners depending on
whether they are light or heavy duty. Clarifiers and
thickeners are essentially tanks with internal baffles,
compartments, sweeps and other directing and segregating
mechanisms to provide efficient concentration and removal of
suspended solids in one effluent stream and clarified liquid
in the other. Usually the stream containing most of the
suspended solids is either sent to a second thickening
vessel or sent directly to a centrifuge or filter for
further concentration to sludge or cake solids.
(c) Filtration
Filtration is the most versatile method for removal of
waterborne suspended solids, being used for applications
ranging from dewatering of sludges to removal of the last
traces of suspended solids to give clear filtrates.
Filtration is accomplished by passing the waste water stream
through solids—retaining screens, cloths, or particulates
such as sand, gravel, coal or diatomaceous earth using
gravity, pressure or vacuum as the driving force.
Filtration equipment is of various designs, including plate
and frame, cartridge and candle, leaf, vacuum rotary, and
sand or mixed media beds. All of these types are currently
used in the treatment of waterborne wastes in the inorganic
chemical industry.
(d) Centrifuging
When the force of gravity is not sufficient to separate
solids and liquids to the desired degree or in the desired
time, centrifugal force can be utilized. Although there are
many types of centrifuges, most industrial units can be
broken down into major categories—solid bowl and perforated
bowl. The solid bowl centrifuge consists of a rapidly
rotating bowl into which the waste stream is introduced.
Centrifugal action of the spinning bowl separates the solids
from the liquid phase and the two are removed separately.
The perforated bowl centrifuge has holes in the bowl through
which the liquid escapes by centrifugal force. The solids
are retained inside the bowl and removed either continuously
or in batch fashion.
Centrifuges are not widely used for inorganic chemical waste
streams when compared to settling ponds, thickeners, or
filters.
(e) Coagulations
205
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Suspended solids often settle slowly or not at all due to
their small particle size and electrical charges. Addition
of a flocculant or coagulant neutralizes these charges,
promotes coagulation of particles and gives faster settling
rates and improved separation.
Coagulants, such as alum, ferric chloride and polymeri^
electrolytes, also aid in the settling cf other suspended
solids that may be present.
Dissolved Materials Treatment
Treatment for dissolved materials consists of either
modifying or removing the undesired materials. Modification
techniques include chemical treatments such as
neutralization and oxidation-reduction reactions. Acids,
alkaline materials, cyanides, chromates, sulfides and other
toxic or hazardous materials are examples of dissolved
materials modified in this way. Removal of dissolved solids
is accomplished by methods such as chemical precipitation,
ion exchange, carbon adsorption, reverse osmosis and
evaporation.
(a) Chemical Treatments
Chemical treatments for abatement of waterborne wastes are
widespread. Included in this overall category are such
important subdivisions as neutralization, pH control, oxida-
tion-reduction reactions, coagulations, and precipitations.
(i) Neutralization
Many of the waterborne wastes of this study are either
acidic or alkaline. Before disposal to surface water or
other medium this acidity or alkalinity needs to be
controlled. The most common method is to treat acidic
streams with alkaline materials such as limestone, lime,
soda ash, or sodium hydroxide. Alkaline streams are treated
with acids such as sulfuric. Whenever possible, advantage
is taken of the availability of acidic waste streams to
neutralize basic waste streams and vice versa.
Neutralization often produces suspended solids which must be
removed prior to waste water disposal.
(ii) pH Control
The control of pH may be equivalent to neutralization if the
control point is at or close to pH7. Sometimes chemical
addition to waste streams is designed, however, to maintain
a pH level on either the acidic or basic side for purposes
206
-------
1)
2)
3)
4)
5)
6)
Cr+3
Fe+3
Mn+2
Zn +
Ni+3
Cu +
* 30H-
+ 3OH-
+ 20H-
20H- =
+ 3OH-
20H- =
= Cr(OH)3;
= Fe(OH)3;
= Mn(OH)2
Zn(OH)2;
= Ni(OH)3;
Cu(OH)2.
= Mn02
and
of controlling desired reactions or solubility as shown bv
Figure 50 (2U) . 7
Examples of pH control being used for precipitatina
undesired pollutants are:
2H+ + 4e-;
Reactions (1) and (2) are used for reiroval of chromium and
iron contaminants involved with chromate reductions.
Reaction (3) is used for removing manganese from
permanganate and manganese sulfate waterborne wastes.
Reactions (4), (5), and (6) are used on waste water from
nickel sulfate, copper salts and zinc salts of this study.
(iii) Oxidation-Reduction Reactions
The modification or destruction of many hazardous wastes is
accomplished by chemical oxidation or reduction reactions.
Cyanides can be oxidized with chlorine or ozone to less haz-
ardous cyanates or to final destruction to innocuous
materials; hexavalent chromium is reduced to the less
hazardous trivalent form with sulfur dioxide or bisulfites.
Sulfites, with large COD values, can be oxidized with air to
inert sulfates. These examples and many others are basic to
the modification of inorganic chemicals waterborne wastes to
make them less troublesome.
Cyanides
The two most common methods of treating cyanides are: (1)
single or two-stage alkaline chlorination and (2)
hypochlorite oxidation.
Alkaline Chlorination
Stage 1
11.5 PH
NaCN * C12 * 2NaOH = NaCNO + 2NaCl + H2O (fast)
Stage 2
2NaCNO + 3C12
QNaOH
7.5 to 9.0 pH
N_ + 2C02 + 6NaCl + 2H20
207
-------
8 9 10
SOLUTION, pH
II
12
FIGURE so
SOLUBILITY OF COPPER, NICKEL,
CHROM1NUM AND ZINC AS A
FUNCTION OF pH
208
-------
(slow)
The stage 1 cyanat.es are stable and less toxic than cyanides
(21) . Stage 2 completes the destruction to nitrogen and
carbon dioxide, but considerably more chlorine and caustic
are required for the overall 2-stage process than for the
single-stage oxidation to cyanate. The reaction is also
slower.
Hypochlorite Oxidation
2NaCN * Ca(OCl)2 = 2NaCNO + CaCl2
2NaCN + 2NaOCl = 2NaCNO + 2NaCl
Either calcium or sodium hypochlorite can be used depending
on economics and availability. For small plants or small
cyanide waste water loads, the recently developed electrical
hypochlorite generators may be useful.
Best practicable control technology for control of total
cyanide and oxidizable cyanide is chlorination. This
technology is capable of achieving effluent concentrations
of 0.5 mg/1 for total cyanide and 0.05 mg/1 for oxidizable
cyanide. This concentration is being achieved for total
cyanide in the electroplating industry at plant numbers 33-
20, 36-1, 20-7, 11-8, 36-12, 15-3, 20-24, 33-24, 33-2, 15-1,
12-6, 33-15, 12-8, 13-1, 6-7, 20-17 and 30-21. This
concentration is being achieved for oxidizable cyanide in
the electroplating industry at plants 33-20, 36-1 and 20-7.
Transfer of technology from the electroplating industry is
the basis for use of these concentrations in establishing
limits in this industry.
Ozone has also been used for oxidation of cyanides(22).
Other methods include boiling and peroxide
decomposition(19).
Complex cyanides are much more resistant to oxidation or re-
moval than simple cyanides. Soluble complex cyanides may
often be removed by chemical precipitation with iron salts
(such as ferrous sulfate) or other heavy metal ions (zinc or
cadmium). Ferro- and ferricyanides as well as other complex
cyanides may be destroyed by either ozone or chlorine
oxidation in acid solution. Ozone appears to be the best
choice(18) .
Complex cyanides are less toxic than oxidizable cyanides and
are stable except to ultraviolet light (sunlight).
209
-------
The proposed mechanism is:
-------
Inorganic sulfur compounds range generally with degree of
oxidation from the very harmful hydrogen sulfide to the
relatively innocuous sulfate salts such as sodium sulfate.
Intermediate oxidation steps include sulfides, thiosulfates,
hydrosulfites, sulfites and finally sulfates.
Oxidation is accomplished with air, hydrogen peroxide,
chlorine and other oxidizing agents.
a) Sulfides (20)
Sulfides are readily oxidizable with air up to the
thiosulfate level. Thiosulfates are less harmful than
sulfides (of the order of 1000 to 1} and approach the
innocuousness of sulfates:
US- + 302 = 25203=
Reaction level is 90-95 percent complete.
b) Thiosulfates
Thiosulfates are difficult to oxidize further with air(23).
They can, however, be oxidized to sulfates with powerful
oxiding agents such as chlorine and peroxides:
5203= + C12 = 2SO4=
52)3= + H202 = 2. ;ft=
Reaction level should be 95-99 percent complete,
c) Hydrosulfites
Hydrosulfites can also be oxidized by oxidizing agents such
as C12 and peroxide, and perhaps with catalyzed air
oxidation:
S2O4= + C12 = 2SO4.
SKM£= + H2O2 = 2SO(t=
Reaction level should be 90-99 percent complete.
d) Sulfites
Sulfites are readily oxidized with air to sulfates at a 90-
99 percent completion level. Chlorine and peroxides would
be expected to perform similar oxidation:
211
-------
2SO3 + O2 = 2SO4
(a) Precipitations
The reaction of two soluble chemicals to produce insoluble
or precipitated products is the basis for removing many
undesired waterborne wastes. The use of this technique
varies from lime treatments to precipitate sulfates,
fluorides, hydroxides and carbonates to sodium or ferrous
sulfide precipitations of copper, lead and other toxic heavy
metals. Precipitation reactions are particularly
responsible for heavy suspended solids loads. Removal of
these suspended solids is accomplished by means of settling
ponds, clarifiers and thickeners, filters, and centrifuges.
The following are examples of precipitation reactions used
for waste water treatment:
1) SO4= + Ca(OH)2 = CaSCW + 2OH
2) 2F- + Ca(OH)2 = CaF2 + 2OH
3) Na2SiF6 + 3Ca(OH)2 = 3CaF2 + SiO2 * 2NaOH + 4H2O
4) BaS * FeSOi = BaSOU + FeS
5) Zn++ + Na2CO3 = ZnCO3 * Na+
6) CrO4= + Pb+2 = PbCrO4_
7) Cu++ + Na2S = CuS + 2Na+
(b) Ion Exchange
Removal of an undesirable dissolved solid in the ionized
form is accomplished through exchange with a more desirable
ion contained in a contacting bed of ion exchange resin.
Example of a widely used application is water softening
where calcium and magnesium ions are removed and replaced
with sodium ions. If the dissolved ions are replaced with
hydrogen and hydroxyl ions from the ion exchange resin, then
the water is "demineralized" of all dissolved solids. When
the resins are loaded with exchanged ions they must be
regenerated with salt, acid, base or other regenerant to be
returned to their original status. Wastes from this
regeneration often constitute a major portion of the
waterborne waste from the process.
Ion exchange techniques are used for removal of chromates,
metallic ions, ammonia, nitrates and other undesirable
212
-------
dissolved materials. Since the removed materials are in
highly concentrated form (often up to 10 percent by weight)
in the regenerant waste, they can often be recovered and
reused or sold profitably.
Demineralization yields water containing very little in the
way of dissolved solids (less than 2-3 mg/liter). This high
quality water is used in boilers, cooling towers, critical
processes and other applications demanding purity.
(c) Carbon Adsorption
On the rare occasions that inorganic chemicals waste streams
contain organic materials, one of the appropriate treatments
to remove organic components is carbon adsorption. When
waste streams containing organic contaminants are passed
through activated carbon beds, the organic material is
adsorbed. When the carbon bed is saturated with this
organic substance, the bed may be regenerated by burning off
the adsorbed organic and returning the carbon to service.
(d) Reverse Osmosis
Essentially, when a semi-permeable membrane separates a pure
liquid and solution of dissolved material in the same
liquid, there is a net migration of the pure liquid to the
solution, driven by the free energy difference between the
two sides of the membrane. Equilibrium is reached only when
the liquids on each side of the membrane are of the same
composition or sufficient additional pressure is applied on
the solution side of the membrane to counterbalance the
osmotic driving force. Application of additional pressure
on the solution side reverses the direction of osmotic flow
through the membrane and results in concentration of the
solution and migration of additional pure liquid to the pure
liquid side. Reverse osmosis may also be looked at as
pressure filtration through a molecular pore-sized filter.
The small pore size of the reverse osmosis membrane is both
its strength and its weakness. Its strength comes from the
molecular separations that it can achieve. Its weakness
comes from the criticalness it has to blinding, pluaging,
and chemical attack. Acidity, suspended solids
precipitations, coatings, dirt, organics and other
substances can make it inoperative. Membrane life is
critical and unknown in many mediums.
The reverse osmosis membranes used commercially are
generally one of two types—flat sheet or hollow fiber For
maximum membrane area in the smallest space, various sheet
213
-------
configurations have been devised including tubes, spiral
winding, and sandwich-type structures. Sheet membranes have
been largely cellulose acetate, while hollow fibers have
been largely polyamides. The type selected depends upon the
specific application.
(e) Evaporation Processes
Evaporation is the only method of general usefulness for tne
separation and recovery of dissolved solids in water. All
others either involve merely concentration (reverse osmosis)
or introduce contaminations for subsequent operations
(demineralizer regenerants and chemical precipitations) .
The evaporation process is well known and well established
in the inorganic chemical industry. Separations, product
purifications and solution concentrations are commonly
accomplished by evaporative techniques. In-depth technology
for handling the common dissolved solids in water waste
streams has been developed in the soda ash, salt, calcium
chloride, and sea water chemical industries. In addition,
numerous desalination plants producing fresh water from
brackish or sea water are scattered all over the world and
have been in operation for a number of years. Sea water
generally has approximately 35,000 ppm dissolved solids (3.5
percent by weight) while brackish water has 2,000 to 25,000
ppm depending on location. Some southwestern U.S. water
supplies contain dissolved solids above 2,000 ppm and have
to be treated similarly to brackish water.
On the other hand, evaporation is a relatively expensive
operation. To evaporate one kilogram of water,
approximately 550 kilogram-calories of energy is required
and the capital cost for the evaporating equipment is not
low. For these reasons, industrial use of evaporation in
treating waste water has been minimal. As the cost of pure
water has increased in portions of the United States and the
world, however, it has become increasingly attractive to
follow this approach.
Almost always, the treatment of waste water streams by
evaporation has utilized the principle of multi-effects to
reduce the amount of steam or energy required. Thus, the
theoretical limitation of carrying out the separation of a
solute from its solvent is the minimum amount of work
necessary to effect the particular change, that is the free
energy change involved. A process can be made to operate
with a real energy consumption not greatly exceeding this
value. The greater the concentration of soluble salts, the
greater is the free energy change for separation, but, even
214
-------
for concentrated solutions, the value is much lower than the
550 kg-cal per kilogram value to evaporate water. Multi-
effect evaporators use the heat content of the evaporated
vapor stream from each preceding stage to efficiently (at
low temperature difference) evaporate more vapor at the
succeeding stages. Thus, the work available is used in a
nearly reversible manner, and low energy requirement
results. However, a large capital investment in heat
transfer surface and pumps is required. The interaction of
the capital equipment costs versus energy or operating costs
will be discussed in detail in the treatment costs section.
(f) Drying
After evaporative techniques have concentrated the dissolved
solids to high levels, the residual water content must still
be removed for either recovery, sale or disposal. Water
content will range from virtually zero up to 90 percent by
weight. Gas or oil fired dryers, steam heated drum dryers
or other final moisture-removing equipment can be used for
this purpose. Since this drying operation is a common one
in the production of inorganic chemicals themselves,
technology is well known and developed. Costs are mainly
those for fuel or steam.
Containment
Rainwater runoff of suspended or dissolved wastes is of
concern for a number of inorganic chemicals plants. Ore
piles, ore residues, and solid wastes as well as airborne
wastes which settle as dusts and mists on buildings and
grounds are contributors. Several plants now contain and
treat rainwater runoff from practically the entire property,
thiough a diking-ditching collection system. Several others
are actively planning for such treatment.
Onlined ponds are the most common treatment facility used by
the inorganic chemical industry. Ponds are often used in
closed loop or zero discharge systems. In dry climates
the pond may serve as disposal basins.
Containment failures of ponds occur because they are
unlined, or they are iirproperly constructed for containment
in times of heavy rainfall.
Unlined ponds may give good effluent control if dug in
impervious clay areas or poor control, if in porous, sandy
soil. The porous ponds will allow effluent to diffuse into
the surrounding earth and water streams. Plastic pond
linings are being increasingly used to avoid this problem.
215
-------
In times of heavy rainfall, many ponds overflow and much of
the pond content is released into either the surrounding
countryside or, more likely, into the nearest body of water.
Good effluent control may be gained by a number of methods,
including:
1) Pond and diking designed to take any anticipated rainfall
-smaller and deeper ponds used where rainfall is heavy.
2) Construct ponds so that drainage from the surrounding
area does not inundate the pond and overwhelm it.
3) Substitution of smaller volume (and surfaced) treatment
tanks, coagulators or clarifiers to reduce rainfall influx
and leakage problems.
Disposal Practices
Disposal of the waterborne wastes from inorganic chemicals
manufacture represents the final control exercised by the
waste producer. A number of options are available, some at
zero or low cost, others at high cost.
Low-cost options include discharge to surface water—river,
lake, bay or ocean—and where applicable, land disposal by
running effluent out on land and letting it soak in or
evaporate.
At somewhat higher costs, wastes may be disposed of into the
municipal sanitary system or an industrial waste treatment
plant. Treatment and reuse of the waste stream can also be
practiced. In dry climates, unlined evaporation ponds, if
allowed, would involve moderate costs.
High-cost disposal systems include lined evaporation ponds.
Such a method is used for wastes which cannot be disposed of
otherwise. These wastes contain strong acids or alkalies,
harmful substances, and/or high dissolved solids content.
Dnlined Evaporation Ponds
TWO requirements must be met for an unlined evaporation pond
to be successfully utilized. First it must be located in an
area in which unlined ponds are allowed, and secondly, the
rainfall in that area must not exceed the evaporation rate.
This second requirement eliminates most of the heavily
industrialized areas. For tne low rainfall areas,
evaporation ponds are feasible with definite restrictions.
Ponds must be large in area for surface exposure. The
216
-------
volume of water evaporation per year can be determined by
the following formula:
Volume = 0.00274 x D x area.
Where D = difference between meters of water evaporated per
year and meters of rainfall per year.
Evaporation of large amounts of waste water requires large
ponds. The availability and costs of sufficient land place
another possible restriction on this approach.
Lined Evaporation Ponds
The lined evaporation ponds now required in some sections of
the country have the same characteristics as developed for
the unlined ponds—large acreage requirements and a
favorable evaporation rate to rainfall balance. They are
significantly higher in cost than an unlined pond. Such
costs are developed in a later section. Reduction of the
evaporation load prior to its ponding is a significant
advantage. For this reason, plus the short supply and high
cost of water in much of the southwestern United States,
distillation and membrane processes are beginning to be
used—either alone or in conjunction with evaporation ponds-
-in these regions.
Municipal Sewers
Although the waterborne wastes from the large volume
inorganic chemicals plants were almost always treated on-
site, the selected segment study revealed a number of plants
that dispose of their wastes to municipal sewer systems.
Disposal by Contractors
Increasing numbers of commercial disposal facilities are be-
coming available. As yet, the inorganic chemicals industry
does not seem to have made significant use of these
services, except for minor amounts of solids, organics
disposal, and small quantities of concentrated hazardous
solutions and sludges.
217
-------
SECTION VIII
COST, ENERGY AND NON-WATER QUALITY ASPECTS
COST AND REDUCTION BENEFITS OF TREATMENT
AND CONTROL TECHNOLOGIES
SUMMARY
Costs for the treatment and control of waterbome pollutants
for inorganic chemicals included in this study have been
developed, for the most part, on a compilation and summation
of costs for individual plants rather than a statistical
projection based on a small fraction of existing plants.
This approach was necessary because many of the chemicals
are made in only a very few plants in the U.S., most or all
of which were studied.
A summary of cost and energy information for attainment of
no discharge of pollutants in process waste waters is given
in Table 5 as developed from the specific chemical overall
cost benefit analyses given later in this section.
For the inorganic chemicals covered^ in this study, treatment
and disposal investment capital already spent is estimated
as $18,000,000. Much of this money has been spent to reach
the minimum treatment level. A fair portion has been spent
for best practicable or best available technology levels.
It is estimated that approximately twice the amount of total
additional capital expenditure is needed to achieve no
discharge of pollutants in process waste water at all
facilities in these industries.
Additional energy required for attaining no discharge of
pollutants in process waste water is estimated to be 1,100
billion kg cal/yr (4,1*00 billion BTU/yr) . This is of the
order of less than 0.05 percent of the energy currently used
in the inorganic chemical industry as a whole. The total
additional capital investment to achieve this level is
estimated to be $27,000,000.
The following chemical subcategories are estimated to
require additional costs for treatment to no discharge of
pollutants in process waste water of more than 4 percent of
their selling prices overall:
boric acid
calcium carbonate
chrome pigments and iron blues
hydroaen cyanide
219
-------
TABLE 5. SUMMARY OF COST AND ENERGY INFORMATION FOR NO DISCHARGE OF HARMFUL POLLUTANTS IN PROCESS WASTE WAIER
SUECATECOKT
? "AX
"RTC ACID
.'I.fTC' CPV.?Q'. \TE
* CT' i'VOT)* IDr
'".HO1- ' >°XJ>'.It'£
hr.OME PICXE.STS
HKO'IIC ACID
:rP::s til FA IE
~rnc c> "GRIDE
T~%x,r:; CYA:.-IL£
^r.-F^/t.',. ,T.
4^4--A^C.VYCLS
:'• i' i:~ii
-, . • . . -A . E
. - - - ^ -
;;• ' ;• ~'~:>rn',' :rr-
-1.; . •- . -t"(-)jj 'rClhcsl
".'A ?'t:r.ss
.:;_; .S-L.'-ATE
CAPITAL SPF3iT
(Collort.)
ecy.o ) i
J50,'. ))
35.'i • i
^50,0 ) 1
3Po oor>
10J.COO
3.700.000
0
25,000
0
0
3,400,000
o
63.000
3,301 CO
7G'>, 00
7, ','0
40, 00
lO./JO
] .500. COO
0
0
0
ADDITIONAL CAPITAL
NEEDED
(Dollar*)
i.ono
0
30.000
3^200,000
] 30, 000
1,500,000
6,900,000
0
100,000
60.000
0
3,800,000
3.000
230, UuO
2. 700. COO
600.000
0
14 . 000
/50.000
8.000
" 600.000
0
0
10.000
ADDITIONAL ENERGY
(Million* kg C«l/y*(MUlieni BTU/y»»
o
_ 0 ._ ...
iotyno_L ''Oj.ogojL
o _ . ..
185,000( 740,000)
. _2jor irooo)
63.000( 249,000)
190.000( 760.000)
n . . .
8.000( 32,000)
0
0
500,000(2,000,000)
0
0
0 ...
0
5oo( 2,000;
500( 2.000!
0
53.00I.K 210.000)
_. _0
o
-0
CURRENT COITS
(ColUi*/M*trie Ton(Doll*»/8hcct Ton)]
— i.SJ'/iJij
1 o.ii'W.W
2^33 "(2.12
0.18 (8.35
0
2,29 (2.08)
0,52 (0.47)'
0
22.33 (20.30)
- - . 0 . .
0
0
0
0
0
0.09 (0.08)
5TZT7OT5
o
0.14 (0.13)
0
0
O.Vii (0,71)
7. 711 (?. 06)
0
'0
6
ADDITIONAL COIT1
(Dollati/Hacrlc Ton(Doll«r«/Jhort Ton)
Ji/3 13.H11
- .... - 0 .
?«.!•• UM.»6)
O.lil (0.7i)
9.8V (H.99)
0 77 (0 70J^
5.49 (4.93)
52.62 (47.84)
0 "
2.2B (?.07)
?.4« (2.21!)
0
3(1.9) (J'j. J9J
o.S.' (o.;5J " '
2.41 (2. IV)
48.77 (/i.'i,Jj)
0 . 0 / ( y 0£)
0
10. ;i (9. 10)
nii.y'j (/ii.4Q
0. 10 CO.//J
y
0
0./5 (6.68>
j
TOTAL
ADDITIONAL COST-! !
(Doll«t«/rr) |
J36 ODD '
PI 3 000
, it — "7,"^^* "
, .l^<(,'yfii_. 1
L ..
rt 1
-------
lithium carbonate (from spodiiBene ore)
stannic oxide (wet process)
rhermal pollution problems were not encountered in this
study nor was noise or other types of pollutions.
In general, plant size and age have only a nominal effect in
influencing the waste effluents and the costs for their
treatment and disposal. Although large plants and complexes
have lower treatment cost per ton of chemical produced when
the same methods are used, the small plants can often use
municipal sewers, land seepage, commercial disposal and
other methods not available or economic to the larger
producers. Plant age indirectly influences treatment and
disposal costs through the effects of isolation and control
of wastes and space limitations and cost. If treatment and
disposal space is available and waste streams are isolatable
then age usually makes little difference.
Geographic location is often a critical factor for waste
treatment and disposal costs. Availability of solar
evaporation is an economic advantage. Also the western
United States has more economic incentive to recover and
reuse water than the East.
Removal of dissolved solids is expensive. The disposal of
soluble solids once they have been removed from the waste-
water is another difficult problem. New plants have more
options in solving these problems economically than do
existing plants. New source facilities with heavy dissolved
solids effluents and/or heavy solid waste loads may avoid
costly waste water treatments by geographical location. A
favorable balance of climatic evaporation to rainfall eases
these problems. Land storage or landfill space should be
available for solids disposal,
New plants being built can avoid major future waste abate-
ment costs by inclusion of: 1) dikes, emergency holding
ponds, catch basins and other containment facilities for
leaks, spills and washdowns, 2) piping, trenches, sewers,
sumps, and other isolation facilities to keep leaks, spills
and process water separate from cooling and sanitary water,
3) noncontact condensers for cooling water, 4) efficient
reuse, recycling and recovery of all possible raw materials
and by-products, 5) closed cycle water utilization whenever
possible. Closed cycle operation eliminates all waterborne
wastes to surface water.
Cost References and Rationale
221
-------
Cost information contained in this report was obtained
directly from industry, from engineering firms, equipment
suppliers, government sources, and available literature.
Whenever possiole, costs are based on actual industrial
installations or engineering estimates for projected facili-
ties as supplied by contributing companies. In the absence
of such information, costs estimates have been developed
from either plant-supplied costs for similar waste treatment
installation at plants makina other inorganic chemicals or
general cost estimates for treatment technology.
In the Cost Analysis tables, the values of invested capital
and annual costs given are the cost to plants that do not
have the specified technology in place now.
Costs have been uniformly calculated oased on 10 percent
straight line depreciation. There is an additional amount
of interest at 6 percent of the depreciated value per year
(pollution-abatement tax-free money). These, plus the costs
of insurance and taxes, yield a total overall annualized
fixed cost of 15 percent per year.
All costs have been adjusted to 1971 values and are q-aoted
as such unless otherwise noted.
Definition of Levels of Treatment and Control
Cost Development
Costs are developed for various levels of technology as
described in Level Descriptions. The A level is the least
stringent of the levels. B, C, D, and E levels are other
levels of treatment that were evaluated.
Treatment and Disposal Rationales Applied to
Cost Developments
The following treatment rationales are employed in the cost
development:
1) All noncontact cooling water is exempted from treatment
(and treatment costs) provided that no pollutants are
introduced.
2) Water treatment, cooling tower and boiler blowdown dis-
charges are not considered process waste water.
3) Disposal considerations are covered in cost development,
including evaporation ponds, land spoilage and solid
wastes handling.
222
-------
INDIVIDUAL CHEMICAL WASTEWATER TREATMENT AN1 BISPOSAL COSTS
Aluminum Fluoride
The wastes from the production of aluminum fluoride include
calcium sulfate, fluorides and fume scrubber contributions.
In plants that use captive production of hydrofluoric acid
to produce aluminum fluoride the wastes from the acid
process are also included.
Pond treatment without neutralization is the minimum level.
Lime treatment of waterborne wastes precipitates fluorides,
silicates and sulfates. Pond settling of precipitates
leaves calcium sulfate and fluoride dissolved to the limits
of their solubility. Recycle and reuse possibilities exist
(in fact have been cited for hydrofluoric acid production in
an earlier study) using several options, but existing plants
still have effluent. Costs for closed-loop systems are
included in the cost-effectiveness development. Additional
expenditures to reach closed-loop status are estimated to be
$3.75/kkg. A cost summary is given in Table 6.
Additional energy requirements even for reuse systems are
small since chemical treatments and pond settling are the
major treatment techniques.
Ammonium Chloride
Ammonium chloride is produced by taking a side stream from
the Solvay soda ash process. Ammonium chloride is also
produced by a no-discharge dry process and as a by-product
of processes to which all wastes are attributable.
For Solvay process by-product, the filter muds and sludges
are returned to the soda ash process. The ammonia waste is
due to contact cooling. New sources would eliminate this by
surface condensers and vacuum pumps. Free ammonia
discharges can be eliminated by neutralization with mineral
acid. An alternative, but more costly, means to remove
ammonia from the existing plant is to completely replace
contact cooling with surface condensers and vacuum pumps.
This alternative would cost S6.67 additional capita1/kkg for
a total of $10.00/kkg and $2.09 additional operating
costs/kkg.
Additional energy requirements for the neutralization
options are small. A cost summary is given in Table 7.
Borax
Borax is produced in the western United States. As such,
the large wastes from the process are disposed of by re-
223
-------
CHEMICAL
TABLE 6
COST ANALYSIS
Aluminum Fluoride
TOTAL PRODUCTION 143,200
METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PROOOCTtON)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
AUDI I U/wAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
fluoride
pH
LEVEL
A
100
11.90
11.90
0
2.55
2.55
0
.15
12
B
65
19.00
11.90
7.10
5.05
2.55
2.50
.43
.34
6-9
c
25
25.00
11.90
13.10
6.30
2.55
3.75
0
0
-
D
LEVEL DESCRIPTIONS:
A = settling pond
B = lime neutralization plus settling pond
C = B plus recycle of scrubber water
i
224
-------
TABLE 7
COST ANALYSIS
CHEMICAL Amronixm Chloride
TOTAL PRODUCTION
16,500
METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
AUDI i iCNAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
antnonia (as N)
PH
LEVEL
A
100
3.33
3.33
0
.56
.56
0
4.4
6-9
B
0
10.00
3.33
6.67
2.65
.56
2.09
0
c
0
3.64
3.33
.31
.67
.56
.11
4.4
6-9
D
LEVEL DESCRIPTIONS:
A = return sodixm chloride and arcnonium chloride to soda ash and replace or
barcmetric condenser.
B = replace all barometric condensers
C = A plus neutralization
225
-------
turning to the source brine lakes or try land storage. Brine
lake return is assumed to be zero cost. The cost of the
land storage option is accounted for in Table 8. Treatment
and disposal of wastes for borax illustrate several coints
discussed elsewr.ere: ^verai points
1) Costs for wastes cannot be treated statistically for manv
chemicals of this study. Brine lake disposal cos^s ar- '
zero, whereas there are disposal costs for land disposal,
2) Wasuewater treatment economics and land disoosal costs
nre aifrerent in the West than in the East/ Solar
evaporation is economically feasible in much of the West.
Kaintail, land cost and availability and value of re-
claimed water are all factors influencing treatment and
disposal options. Distillation of water for reuse in
the water-short parts of the West is often economically
feasible. J
J-lff';l1 costs for borax waste treatment and storage are
S1.87/k
-------
TABLE 8
COST ANALYSIS
CHEMICAL Borax (°re mini
TOTAL PRODUCTION 360,000
METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
{DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
AUDI i iCNAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
COD
LEVEL
A
100
0
0
0
0
0
0
B
100
5.52
5.52
0
2.33
2.33
0
0
0
c
0
13.20
5.52
7.68
4.20
2.33
1.87
0
0
D
LEVEL DESCRIPTIONS:
A = no treatment
B = lined evaporation ponds
C = distillation
227
-------
CHEMICAL
TABLE 9
COST ANALYSIS
••
Boric Acid (non-Trona)
TOTAL PRODUCTION
70,800
METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
ADDITIONAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
arsenic
pH
LEVEL
A
100
1.93
1.93
0
.38
.38
0
B
0
2.95
1.93
1.02
1.29
.38
.91
.07
.0036
6-9
c
0
45.20
1.93
43.27
24.53
.38
24.15
0
0
-
D
LEVEL DESCRIPTIONS:
A = clarification
B = A plus arsenic removal
C = evaporation of wastes and reuse of water
228
-------
are not additional costs since all bromine facilities
already have incurred them. Additional costs for the plants
that do not have this treatment now are $0.83/kkg (See Table
10).
Energy requirements are negligible.
Calcium Carbonate
Calcium carbonate is made by several processes from
different raw materials. Anticipated additional costs to
achieve no discharge of pollutants and for two intermediate
levels are given in Table 11.
Since the intermediate treatments are chemical treatment,
pond settling and filtration, energy requirements are small.
Substantial energy is required for total evaporation as
shown in Table 5. Total evaporation is required to
eliminate suspended solids unless recycle uses for the
treated waste water can be found in the plant complexes.
Calcium Hydroxide
Calcium hydroxide wastes are small ana involve only kiln
dust scrubbing. If scrubber waste costs are assessed to
calcium oxide (quick lime) production then waterborne waste
treatment cost for calcium hydroxide is essentially zero.
The estimated costs presented in Table 12 are only for
calcium hydroxide, not slaked lime, which is an agricultural
product. Additional energy requirements are negligible.
Carbon Monoxide
Carbon monoxide production wastes consist of oils, organics
and scrubber wastes and they are small in volume. Other
wastes are dissolved solids from blowdowns and ion exchange
regenerations but they are not included since they either do
not have other pollutants or can be modified to have none.
Cost breakdowns are given in Table 13. Additional energy
requirements are negligible.
Chrome Pigments and Iron Blues
Chrome pigments of this study included zinc yellow, chrome
yellow, molybdate chrome orange, chrome green and chromic
oxide. Iron blues are included in this analysis because
they are always made in chrome pigment complexes, and are
used in part to make chrome green. The waterborne wastes
from chrome pigments manufacture contain a variety of
hazardous materials and the wastes from these plants are
229
-------
TABLE 10
COST ANALYSIS
CHEMICAL
Brondne
TOTAL PRODUCTION
41,SCO
METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRO-jCT'CN)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/ METRIC TON PRODUCED)
TOTAL
NOW SPENDING
ADD] 1 IwlNAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
harmful pollutants
LEVEL
A
100
0
0
n
c
0
0
0
0
c
B
36
3.36
0
3.36
.83
C
.83
0
0
C
D
LEVEL DESCRIPTIONS;
A = return to brine source (considered part of process)
3 = A plus spill, leak isolation and return to brine source
230
-------
TABLE 11
. ' . • .
: COST ANALYSIS
CHEMICAL Calcium Carbonate (precipitated)
TOTAL PRODUCTION 181,500 METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
AUDI i iGNAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
pH
LEVEL
A
100
5.4!
5.4J
0
2.29
2.29
0
B
36
6.83
5.45
1.38
3.44
2.29
1.15
0.28
6-9
C
0
10.86
5.45
5.41
5.45
2.29
3.16
0.17
6-9
D
0
25.58
5.45
20.13
12.18
2.29
9.89
0
LEVEL DESCRIPTIONS;
A = pond settling
B = A plus neutralization
C = B plus polish filtration
D = B plus evaporation
231
..1
-------
TABLE 12
COST ANALYSIS
CHEMICAL Calcium Hydroxide
TOTAL PRODUCTION
58,400
METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
ADDITIONAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
LEVEL
A
0
0
0
0
0
0
0
B
50
5.76
2.88
2.52
1.19
.59
.60
25ppm
c
40
6.30
2.52
3.78
1.29
.52
.77
0
D
LEVEL DESCRIPTIONS;
A = no dust scrubbers or bag collectors
B = wet dust scrubbers
C = dry bag collectors
232
-------
TABLE 13
CHEM'CAL Carbon Monoxide & Hydrocer
TOTAL PRODUCT.ON CO-14C.GCO
METRIC TCNS PER YEAR
nc -;su,uuu
~:'RCZNT OF INDUSTRY AT LEVEL
!: .'VESTED CAPITAL COSTS
U-l.t-J-A^S/METRiC "sCii CF ANNUAL rTODUCTICN)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
/DC'_LAPS/.ViETRIC TCN1 PRODUCED}
TOTAL
HO\V SPENDING
ADDITIONAL
WASTE LOAD PARAMETERS
'< _C3~.*-Vj/VETHiC TON OF PRODUCT)
TSS
COD
pH
i
LEVEL
A
60
.75
0
.75
.15
0
.15
0.06
D.25
6-9
B
0
10.97
0
10.97
5.49
0
5.49
0
0
C
0
1.10
0
1.10
0.22
0
0.22
0.017
0.065
6-9
D
A = oil seoaration, nejtralizaticn, sludge disposal
B = evaporation
C = segrecation of wastes pljs '
233
-------
complicated further by the manufacture in the same
facilities of iron blue and its contribution of cyanide
wastes.
Soluble chromates such as sodium and potassium have to be
treated for chromate reduction and precipitation. Zinc
salts have to be precipitated. Insoluble chromates, such as
lead salts, are removed by precipitation and removal as sus-
pended solids. Cyanide wastes have to be oxidized to
cyanate. Dissolved solids are very high (approximately
20,000 mg/liter). Costs are given in Table 14.
Chromic Acid
Chromic acid is produced from sodium dichromate. Since
chromic acid is produced in the same facilities as the di-
chromate, treatment and disposal of any leaks and spills or
other waste are handled in the same system. The wastes from
chromic acid are relatively small and are already included
in the whole waste of the sodium dichromate facility as
analyzed in an earlier program,, Further attribution of
wastes or cost to treat chromic acid production would be
redundant and misleading, since they are covered by the
dichromate production in both instances of U.S. production.
New facilites by this process would be essentially covered
by the same analysis.
Copper Sulfate
The high value of copper justifies treatment and recovery of
most wastes and minimizing the metal content in the water
effluent. Tables 15 and 16 summarize costs for treatment
facilities for processes starting with pure copper or with
recovered copper raw materials- Present treatment reduces
pollutants to a low value. Small additional funds or energy
requirements will be needed.
Ferric Chloride
Wastes from the ferric chloride process are sludges, leaks
and spills. Disposal of solid waste sludges plus recycle of
leaks and spills costs $2.48/kkg. Additional energy
requirements will be small. Table 17 summarizes the cost
information.
Fluorine
Fluorine is used principally in classified operations of
the Atomic Energy Commission(AEC). The only non-AEC
facility has no waterborne discharge because of a process
234
-------
235
(THIS PAGE BLANK INTENTIONALLY)
-------
TABLE 15
COST ANALYSIS
CHEMICAL Copper Sulfate (pure raw material)
TOTAL PRODUCTION 12,250 METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
ADDITIONAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
copper
pH
LEVEL
A
0
.80
0
.80
.16
0
.16
0.0002
6-9
B
C
D
LEVEL DESCRIPTIONS:
A = recycle of all process water, leaks and spills and washdowns.
236
-------
TABLE 16
COP-"*" .*,***' V "^ ^
Ui; ;.,.;u_!C^-
CHEMICAL Copper Sulfate (recovery process)
TOTAL PRODUCTION 16»400 VIVC TONS FI
L£
PERCENT OF INDUSTRY AT LEV,:.L
INVESTED CAPITAL COSTS
(DOLLARS/VETSiC TON OF ANNUAL PRODcCTiD'i)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DC_LARS/' ET^C TON PRODUCED)
TOTAL
NOW SPEI;D:NG
ADDITIONAL
WASTE LOAD PARAMETERS
{KILCoRAMS/YiTR'C TON OF PRODUCT)
TSS
copper
nickel
selenium
pr
> !
H ;
90
.61 !
0 i
.61
.7?
«
u
.7C
0.023
0.0005
0.0005
0.0005
6-9
LEV
B j
0
6.78
0
6.78
2.28
0
2.28
0
0
0
0
.
i
i
c
1.22
0
1.22
0.79
0
0.79
i
!
r-i
U
3.15
0
3.15
1.7P; .
0
1.78
0.0046
0.0046_
o.oc-c
0.0023
F.Q
i rr\/r; nc-^^^'.
L. i— V i_ L_ L/: iy~l.
\ =• line, settle, filter
C = evaporation
C = nond lirin^ plus /
2 = / olus water urilance centre]
237
-------
TABLE 17
COST ANALYSIS
CHEMICAL Ferric Chloride
TOTAL PRODUCTION
75,000
METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
ADDITIONAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
iron compounds
LEVEL
A
10
.83
0
.83
1.78
0
1.78
0
0
B
10
.83
0
.83
2.48
0
2.48
0
0
c
D
LEVEL DESCRIPTORS;
A = closed system
B = A plus sludge disposal
238
-------
difference, namely electrolyzing the liquid hydrogen
fluoride rather than the fluoride fused salt electrolyte.
The estimate of the amount of total fluorine produced in the
U.S. that is non-AEC is 10 percent.
The effluent limitations contained herein apply to the
liquid hydrogen fluoride electrolysis process only. No
additional costs or energy are required for the liquid
hydrogen fluoride electrolysis process.
Hydrogen
Hydrogen is made chiefly from two sources: purification of
refinery by-product gases and as a coproduct in the manu-
facture of carbon monoxide. The latter accounts for an
estimated 21 percent of the total U.S. production of
hydrogen (30,000 kkg/yr) . The costs to treat this material
have been allocated totally to carbon monoxide manufacture.
For refinery by-product gas (estimated 110,000 kkg/yr) there
are no process contact waters. There are only cooling tower
and boiler blowdowns. The additional costs and energy to
treat process contact waters are therefore zero.
Hydrogen Cyanide
There are no attributable wastes or costs to hydrogen
cyanide manufacture as a by-product from acrylonitrile
production. The wastes from the Andrussow process
manufacture of hydrogen cyanide include residual oxidizable
cyanides, complex cyanides, ammonia and ammonium salts,
acids and organics. The removal of residual ammonia is
carried out by two different means at various facilities: a
patented phosphoric acid absorption and regeneration, and a
sulfuric acid scrubbing. For the latter, the waste acid is
sold to other processes. Table 18 gives costs for two
different treatment approaches—one biological and the other
chemical. Both are reported to destroy oxidizable cyanides
to very residual levels. Complex cyanides are not affected
by either system.
Overall average treatment costs are given in Table 18. The
costs to arrive at no discharge of pollutants depend greatly
on whether or not the spent sulfuric acid from ammonia
scrubbing can be used elsewhere.
Iodine
As for bromine, iodine is extracted from brines taken from
wells or sea water. Depleted brines are returned to source.
239
-------
TABLE 18
12€,OGG
Vr.T.Tir.
TO'-: FrLH YFJ.H
r
f
i
1
--• - •-.- OF INDUSTRY /.".' LEVEL
in, £1 TED CAPITAL COSTS
(Cr. .-"/MTR1C TON OF ANNUAL Fr.CZXTiCN)
TOTAL
SPENT
ADDITIONAL
~ - .. ;.v.r..'U'!. COSTS
TOTM
NOW SPC;D,;.G
ADDITIONAL
,<' •'- /i/-'- TRIG TCN OF PriC^CT)
TSS
ammonia (as 11}
cvanide
cyanide A
I BCD5
! pii
i
A
54
12.60
0
12.60
4.05
C
4.05
B
21
49.50
0
49.50
ILdl
0
15.43
1.2
0.18
0.05
fUXOS-
1.8
6-9
1
C
o
13^
0
13.86
4,60
0
4.60
1.2
0.18
0.05
0.0015
1.8
6-9
D
C
115.00
0 .
115.00
IP en
0
38.93
0
0
o
Q
?
-
E
o i
53.00
,,.0
53.00
16.57
0
16.57
0.45
j 0.016
0.0023
o.oon?.il
0.096 |
6-9
ettlinc, oil seraraticr 5 rputrc.lizaticn, aeration,
Verification, sludge cp'v
nc>":pation, anmonia recovery unit, settling1
j.v eve r
f!o"! reduction
240
-------
The only waterborne wastes are from leaks and spills. Iso-
lation of these leaks and spills is estimated to cost
$0.82/kkg additional. Additional energy requirements are
negligible.
Table 19 summarizes the cost effectiveness information.
Iron Blue
The manufacture of iron blue is done in complexes that also
produce chrome pigments. As such, the treatment systems are
common for the two types of materials. Costs are combined
with those for chrome pigments.
Lead Monoxide
One process of lead oxide uses no water. Another process
has washdowns and some water effluents which need to be
treated. Summaries of cost effectiveness are given in Table
20. Additional overall average costs for waste treatment to
achieve no discharge of pollutants are $2.41/kkg.
Additional energy requirements are negligible.
Lithium Carbonate
Lithium carbonate is produced from western brine lakes and
from ore. Brine lake processes return wastes to the lake
without treatment and require no additional costs for treat-
ment. Ore processes have water effluent containing
primarily calcium and sodium sulfates as dissolved solids.
These solids can be reduced by distillation processes and
storage of solid calcium sulfate on land, but the cost is
high (estimated $50/kkg).
Table 21 summarizes the cost effectiveness data, including
the solids reduction option discussed above.
Without reduction of dissolved solids the additional treat-
ment costs are low, as are the additional energy
requirements.
Nickel Sulfate^
Nickel sulfate waste water volumes are small but contain
hazardous nickel salts. The nickel from these salts is
removed by precipitation of the hydroxide. This technique
is very pH-sensitive. The precipitate is then removed by
filtration. Table 22 summarizes the treatment costs
involved. Additional energy requirements are small to get
241
-------
TABLE 19
COST ANALYSIS
CHEMICAL
Iodine
TOTAL PRODUCTION
990
METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
ADDITIONAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
harmful pollutants
LEVEL
A
100
*
B
0
3.27
0
3.27
.82
0
.82
0
c
D
LEVEL DESCRIPTIONS:
A = return wastes to brine cavity, leaks discharged
B = contain leaks and spills and return to brine cavity
*Cests are considered part of the manufacturing process
242
-------
TABLE 20
COST ANALYSIS
CHEMICAL Lead Monoxide
TOTAL PRODUCTION
137,000
METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
AUDI 1 iuNAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
lead
LEVEL
A
100
.13
.13
0
.09
.09
0
0.04
0.04
B
20
3.43
.13
3.30
1.20
.09
1.11
0.04
O.C02
c
20
10.30
.13
10.17
2.50
.09
2.41
0
0
D
LEVEL DESCRfPT/ONS;
A = ponding
B = lead precipitation, settling, filtration
C = reuse of washdown water
243
-------
TABLE 21
COST ANALYSIS
CHEMICAL Lithiun Carbonate (from Spodumene Ore)
TOTAL PRODUCTION 12,250 METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
AuumONAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
pfl
LEVEL
A
100
11.70
11.70
0
2.43
2.43
0
.9
6-9
B
0
248.00
11.70
236.30
51.20
2.43
48.77
0
0
c
0
20.00
11.70
8.30
3.75
2.43
1.32
.54
6-9
D
LEVEL DESCRIPTIONS:
A = neutralization and settling
B = A plus evaporation
C = A plus filtration
244
-------
TABLE 22
COST ANALYSIS
CHEM|CAL NickelSulfate_
TOTAL PRODUCTION
15,200
METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
*uui j iUNAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
nickel ion
pH
LEVEL
A
50
1.63
0
1.63
1.88
0
1.88
0.11
0.013
6-9
B
0
4.90
0
4.90
2.74
0
2.74
0.11
0.013
6-9
c
0
68.50
0
68.50
50.28
0
50.28
0.11
0.013
6-9
D
0
32.31
0
32.31
19.75
0
19.75
0
0
-
LEVEL DESCRIPTIONS;
A = precipitation and filtration for a large unit that is part of a cccplex
B = precipitation, filtration and clarification for a large unit that is
not part of a complex
C = precipitation and filtration for a stall plant (1 ton per day)
D = evaporation
245
-------
to a low concentration of nickel in the effluent, but to
have no discharge are substantial as shown in Table 5.
Nitrogen and Oxygen
These two chemicals are produced together. As is common for
industrial gases, the wastes are small. Oil separators are
the only treatment facilities required.
Table 23 gives the cost effectiveness values. An overall
average additional $0.07/kkg cost is estimated. Additional
energy requirements are negligible.
Potassium Chloride
Potassium chloride is another chemical produced only in the
arid part of the West. Soluble wastes are disposed of by
land evaporation and storage. As such disposal costs are
very low. No additional money or energy should be required
beyond what is now being done.
Table 2U summarizes the cost effesctiveness information. In
the event that disposal regulations should require lined
evaporation ponds in the future, costs would increase
significantly.
Potassium Iodide
Treatment and disposal costs for potassium iodide wastes de-
pend on the technology used. One plant, in a dry climate,
has no discharge to surface water. Wastes are collected in
an evaporation pond. Another plant discharges directly
without treatment into a municipal sewer.
Cost effectiveness values are shown in Table 25. Additional
overall average costs of $10.23/kkg for no discharge of
pollutants.
Silver Nitrate
Considering the high value of silver, wastes containing only
small amounts of silver compounds can be economically
treated. Recovery values of the silver more than pay for
treatment costs. Since most of the industry already has
notable treatment facilities, only a small additional cost
of $1.11/kkg is anticipated (see Table 26) to recover all
but a very small amount of the silver, and negligible
additional energy is required.
246
-------
TABLE 23
COST ANALYSIS
CHEMICAL Nitrogen & Oxygen
TOTAL PRODUCTION 6,100,000 (N|)
METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF AMMUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
ADDITIONAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
oil and grease
LEVEL
A
100
.50
.50
0
.11
.11
0
6-9ppm
B
2
.82
.50
.32
.18
.11
.07
0
c
D
LEVEL DESCRIPTIONS:
A = oil separators/ pond
B = isolation of oil-containing vater, separation, and disposal
247
-------
CHEMICAL
TABLE 24
COST ANALYSIS
Potassium Chloride
METRIC TONS PER YEAR
TOTAL PRODUCTION 2,540,000
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
AuDiTiOnAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
harmful pollutants
LEVEL
A
100
.26-. 47
.26-. 47
0
.11-. 17
.11-. 17
0
0
0
B
c
D
LEVEL DESCRIPTIONS;
A = evaporation ponds
248
-------
TABLE 25
COST A;.VV.VS!S
i r t<..ssnir ;r en :'c
TOTAL SJRODUC
:, _rr;'C T- •;.: PER YEA;;
LEVEL
1
P-TVN7 Or i"^...;~. Y ~ '...TVcl.
i
: * iv - t^'Y'^'T^ /"' f ' ^ ' " * ! i'v.^ C*r C
i,.vc.biL.u ( •- . 1 1 :.. Cwiii>
{DOLLARS/METRIC ION C~ A\i\UA_ F,->0:.CT!ON)
TOTAL
SPENT
ADDITIONAL
TCTAL AiviJU/L COSTS
(DCLi A\S/f.iETWC TGN i--';; .ID'
i TOTAL
NOV/ SPEN:.:NS
ADDiTif-: .L
\<"-zi~~ i r\f\r\ C',"' ~ ' ^ '^"r^^o
\i,~>.^> i C. H.JMU ri-ii\.-i ; •— i i— i\o
[K!'_C '-•-.' ;V?-^TRIC T0\: C.~ \-T?VCT)
T1S
sulfide
iron
bariur-
PH
)
, 1
"
23
6.00
0
6.00
3 .03
,1
3 . OL
. <- ,1-3 . _
0.005
O.OOb
0.003
f-9
|
i
[
b
33
27.30
0
27.30
10.23
0
10.23
0
0
0
Q
-
c
0
15.30
0
15.30
4.6C
0
4.cO
C.oK
0.0036
0.003f
0.0023
C-9
D !
»
!
t
j
i
" = chenical rrecipitaticn, clarification
L = evaporation
C = A olus in-process .vaste water flo.v reduction
249
-------
TABLE 26
COST ANALYSIS
CHEMICAL Silver Nitrate
TOTAL PRODUCTION 3'100
METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
AUDI i lONAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
silver
PH
LEVEL
A
63
11.76
0
11.76
4.11
0
4.11
0.020
0.003
6-9
B
0
235.00
0
235.00
82.45
0
82.45
0.020
0.003
6-9
c
0
235.00
0
235.00
86.25
0
86.25
0
0
D
LEVEL DESCRIPTIONS:
A = biological treatment, silver reoovery unit, neutralization and
clarification in a complex
B = same as level A for an isolated plant
C = A plus evaporation of filtrate ard
of solids
250
-------
Value of recovered silver is approximately $270/kkg of
silver nitrate produced. The costs to attain no discharge
of pollutants is also shown in Table 26 and the energy
required is shown in Table 5.
Sodium Fluoride
Conversion of the sodium fluoride process to closed- loop re-
cycle status is a distinct possibility. Additional overall
average costs are $Q.30/kkg. Additional energy costs are
negligible. Table 27 details these costs am? an additional
option of evaporation of waste water.
The v;aste water from the sodium silicof ." •.?;>ri<3e plants
contain residual product, hydrochloric acid, and • >diun
chloricle-"all in large quantities, Treatrr-en{ and disrcta 1
techljiques differ--one plant deep well 12 all wast- w-,tox ,
another treats rind discharges to salt wattri „ while j rhir;
treats and discharges to hraekinh wat'-r.
~;\/i;
Table ?° gives cost effectiveness values. I
r.Q*-e-j that large quantities of money have oirr,:: j\ h-r er spt'
to :«-ach the pr*.L-ent levels.. Addition;-; I er:^t_y t *. ^uii >' ii.en
t.o achieve <\o 5jscharqe ot roLlutants a4 < • ', t -.ciliti-" ? c •
?h(JW3i in Table b.
-------
TABLE 27
COST ANALYSIS
CHEMICAL Sodium Fluoride (silioo fluoride process)
TOTAL PRODUCTION 6,400 (all processes)METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTiON)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
ADDITIONAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
fluoride
&
LEVEL
A
100
2.04
2.04
0
0.38
0.38
0
25HTO
20ppm
6-9
B
0
5.74
4.15
1.59
1.08
.78
.30
0
0
_
c
D
LEVEL DESCRIPTIONS:
A = neutralization in complex treatment system
B = entire complex recycle
252
-------
TABLE 28
COST ANALYSIS
- CHEMICAL
Sociurr. Silicofluoride
TOTAL PRODUCTION
r4,3CC
N'ETR'C TONS PER
• -
. PERCENT OF !\DUSTRY AT LEVEL
> INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDITIONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
ADDITIONAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
fluoride
pH
„
-
LEVEL
A
ICC
22.32
22.32
0
7.7E
7. 78
0
0.3
0.25
6-9
B
67
38.76
22.32
16.44
12.86
7.78
5.08
0
0
-
c
»
D
LEVEL DESCRIPTIONS:
* A = lime neutralization and settling
B = evaporation and land disposal
253
-------
COST ANALYSIS
CHEMICAL zjnc Sulfate
TOTAL PRODUCTION 38,300
METRIC TONS PER YEAR
PERCENT OF INDUSTRY AT LEVEL
INVESTED CAPITAL COSTS
(DOLLARS/METRIC TON OF ANNUAL PRODUCTION)
TOTAL
SPENT
ADDI I lONAL
TOTAL ANNUAL COSTS
(DOLLARS/METRIC TON PRODUCED)
TOTAL
NOW SPENDING
AuUJiiONAL
WASTE LOAD PARAMETERS
(KILOGRAMS/METRIC TON OF PRODUCT)
TSS
LEVEL
A .
66
4.57
0
4.57
0.75
0
0.75
0
B
C
D
-
1
L
P
LEVEL DESCRIPTIONS:
A = recycle of all process water, leaks and spills
254
-------
TABLE 30
ESTIMATED JUNE 1973 U..S. MARKET PRICE OF SIGNIFICANT INORGANIC CHEMICALS
— (IN DOLLARS/TOR) ~
ro
en
Chemical
Aluminum Fluoride
Ammonium Chloride
Ammonium Hydroxide
Barium Carbonate
Borax
Boric Acid
Bromine
Calcium Carbonate
Calcium Hydroxide
Carbon Dioxide
Carbon Monoxide
Chrome Green
Chrome Yellow and
Orange
Chromic Acid
Chromic Oxide
Copper Sulfate
Cuprous Oxide
Ferric Chloride
Ferrous Sulfate
Fluorine
Hydrogen
Hydrogen Cyanide
Iodine
Iron Blues
Selling Price
Range
270 - 350
380
80
120 - 160
60- 100
HO-200
300 - 360
20-60
20
30
250
1,000- 1,240
800 - 1,000
575 - 765
1,000-1,200
430 - 500
1,300- 1,800
80
14-24
32,000
650
230
4,100-4,500
1,250
Chemical
Lead Oxide
Lithium Carbonate
Manganese Sulfate
Molybdate Chrome
Orange
Nickel Sulfate
Nitric Acid (Strong)
Nitrogen
Oxygen
Potassium Chloride
Potassium Iodide
Potassium Permanganate
Silver Nitrate
Sodium Bisulfite
Sodium Fluoride
Sodium Hydrosulfide
Sodium Hydrosulfite
Sodium Silicofluoride
Sodium Thfosulfate
Stannic Oxide
Sulfur Dioxide
Zinc Oxide
Zinc Sulfate
Zinc Yellow
Selling Price
Range
1,000
1,100
90-110
1,000
700-1,000
900- 1,600
20
18
20-35
4,000-5,200
730
12,000-50,000
130
360 -460
110-160
450 - 600
160 - 180
110-220
4,000
60
380
140 - 260
700-830
-------
either from the U.S. Bureau of Census 1971-1972 data (7, 8),
from the Chemical Marketing Reporter, June 1973, or were
obtained directly from the manufacturers. Generally, where
a range is shown, the lower value represents census data and
the higher value is from the Chemical Marketing Reporter.
256
-------
SECTION IX
EFFLUENT REDUCTION ATTAINABLE THROUGH THE
APPLICATION OF THE
BEST PRACTICABLE CONTROL TECHNOLOGY
CURRENTLY AVAILABLE
The effluent limitations which must be achieved by July 1,
1977, are based on the degree of effluent reduction attain-
able through the application of the best practicable control
technology currently available. For the inorganic chemical
industry, this level of technology was based generally on
the average of the best existing performance by plants of
various sizes, ages, and chemical processes within each of
the industry«s subcategories. Each chemical subcategory
will be treated separately for the recommendation of
effluent limitations guidelines and standards of
performance.
Best practicable control technology currently available
emphasizes treatment facilities at the end of a
manufacturing process tout also includes the control
technology within the process itself when it is considered
to be normal practice within an industry. Examples of waste
management techniques which were considered normal practice
within the inorganic chemicals industry are:
a) manufacturing process controls;
b) recycle and alternative uses of water; and
c) recovery and/or reuse of waste water constituents.
Consideration was also given to:
a) The total cost of application of technology in relation
to the effluent reduction benefits to be achieved from
such application;
b) The size and age of equipment and facilities involved;
c) The process employed;
d) The engineering aspects of the application of various
types of control techniques;
e) Process changes; and
f) Non-water quality environmental impact (including energy
257
-------
requirements) .
The following is a discussion of the best practicable
control technology currently available for each of the
chemical subcategories, and the proposed limitations on the
pollutants in their effluents.
General Water Guidelines
Process water is defined as any water contacting the
reactants, intermediate products, by-products or products of
a process including contact cooling water. All values of
guidelines and limitations presented below are expressed as
a 30-day average in units of kilograms of pollutant per
metric ton of product (pounds of pollutant per ton of
product) produced. The daily maximum limitation is double
the monthly average in most cases. However, the maximum for
any one day limit based on BPCTCA is three times the 30 day
average for the following batch processes: chrome pigments,
copper sulf ate, lithium carbonate (spodumene ore) , nickel
sulfate, potassium iodide and silver nitrate. All process
water effluents are limited to the pH range of 6.0 to 9.0.
PROCESS WASTE WATER GUIDELINES AND LIMTTATTnN.g *T>g_T
SIGNIFICANT INORGANIC CHEMICALS POINT SOURCE SUBCATEGORIES
The twelve subcategories (aluminum fluoride, boric acid,
calcium carbonate, carbon monoxide, chrome pigments, copper
sulfate, hydrogen cyanide, lithium carbonate, nickel
sulfate, potassium iodide, silver nitrate and sodium
silicofluoride) which specify total suspended solids as a
regulated parameter for 1977 utilize settling ponds or
clarifiers and, in some cases, filtration systems as the
basis for the best practicable control technology currently
available. Proper design and operation of treatment systems
will achieve 15 mg/1 TSS with settling or clarification and
easily less than 10 mg/1 with filtration. To achieve these
levels requires skilled operation and time to develop these
skills. Correspondingly, the 1977 guidelines are based on
the Agency's best engineering assessment of the effluent
reduction attainable by this technology by 1977 and are
generally set at 25 mg/1 TSS except for the carbon monoxide
and by-product hydrogen subcategory which utilizes 10 mg/1
TSS as the guideline basis to reflect currently attained
levels of treatment by the industry and for the silver
nitrate subcategory which utilizes 15 mg/1 TSS to reflect
current levels of treatment.
ALUMINUM F-LUQRIDE Production Subcategory
258
-------
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is:
_..,.- ^ Effluent Limitation -
Effluent Characteristic *2468
aluminum 0< 17 (0.34)
The above limitations were based on an average process
wastewater discharge of 17,000 liters per metric ton (4,100
gallons per ton) of product.
Best practicable control technology currently available for
the manufacture of aluminum fluoride by the hydrated alumina
hydrogen fluoride process is lime treatment of the scrubber
waste followed by removal of the precipitated calcium
fluoride in settling ponds or clarifiers.
To implement this technology at plants not already using the
recommended control techniques would require the
installation of lime treatment tanks, the necessary piping
and pumps to transport the scrubber waste and the
construction of a settling pond or installation of a
clarifier.
Reason for Selection
The BPCTCA was recommended because it effectively controls
pollutants from this segment of the industry in a reasonably
economical and efficient manner by a technically feasible
system.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $450,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately 0.8 percent
of the selling price of this product.
Approximately 65 percent of this industry subcategory is
presently achieving this level of pollutant discharge by
various methods.
259
-------
Age and Size of Equipment and Facilities
The data obtained on the aluminum fluoride subcategory
represents plants with ages ranging from 8 to 11 years with
similar production capacities.
The best control technology currently available is
practicable regardless of the size or age of plants since
the use of existing technologies is not dependent on these
factors. Also, the similarities in processes used and waste
water characteristics in this production subcategory
substantiate the practicality of these technologies.
Process Employed
The general process employed in the aluminum fluoride
production subcategory involves the reaction of hydrogen
fluoride with hydrated alumina to form aluminum fluoride and
water.
The processes used by the chemical plants in this
subcategory are very similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in the aluminum fluoride production subcategory
because two of the three known plants are already achieving
the recommended effluent limitation guidelines and the re-
maining plant should be able to meet the guidelines with the
installation of a lime treatment facility.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control techno-
logies are presently being used by plants in this production
subcategory.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents wnich could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
260
-------
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy
requirements for the implementation of the recommended
treatment technologies,
AMMONIUM CHLORIDE Production Subcateqory
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available for
ammonium chloride recovery from sodium carbonate is:
Effluent Limitation
Effluent Characteristic kq/kkcr (lb/ton>
Ammonia (as N) 4.1 (8.8)
The above limitations were based on an average process waste
water discharge of 173,700 liters per metric ton (44,500
gallons per ton) of product.
No discharge of process waste water pollutants to navigable
waters in the limitation for ammonium chloride production by
the reaction of anhydrous ammonia with hydrogen chloride
gas.
Identification of BPCTCA
Best practicable control technology currently available for
the manufacture of ammonium chloride as a by-product of the
Solvay process is to neutralize ammonia-containing
barometric condenser cooling water with a mineral acid
before discharge. All other wastes from this process are
attributable to and returned to the Solvay process.
Ammonium chloride by the anhydrous hydrogen chloride and
anhydrous ammonia process is a no discharge process.
Ammonium chloride by the aqueous hydrogen chloride and
ammonia process is not covered in this study.
To implement this technology at plants not already using the
recommended control techniques would require the
installation of mineral acid metering equipment and stream
monitoring instrumentation (Solvay by-product only).
Reason for Selection
261
-------
The neutralization of entrained ammonia in contact cooling
water by a mineral acid such as hydrochloric would eliminate
free ammonia and prevent the formation of suspended solids
in the discharge. The one plant presently using this
process generates approximately 23 kilograms of suspended
solids per metric ton of product (46 Ibs/ton) by allowing
the ammonia-containing condenser water to react with the
high calcium content of the complex's cooling water stream
(Solvay byproduct only) .
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $5,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to less than 0.1 percent of
the selling price of this product.
Approximately HO percent of this industry subcategory is
presently achieving this level of pollutant discharge.
Age and Size of Equipment and Facilities
The data obtained on the manufacture of ammonium chloride as
a Solvay by-product represents a single plant that is
approximately 12 years old.
Process Employed
The general process employed in the manufacture of ammonium
chloride as a Solvay by-product involves the recovery of
part of the dissolved solids waste generated by the Solvay
process. Ammonium chloride is crystallized from a Solvay
process liquor containing ammonium chloride, sodium chloride
and free ammonia. Residual mother liquor is returned to the
Solvay process waste recovery and treatment systems.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in the manufacture of ammonium chloride as a
Solvay by-product because the single plant which
manufactures ammonium chloride by this process passes all
condense: water containing entrained ammonia through a hot
well prior to discharge to the main complex cooling water
stream. A mineral acid metering system could be installed
at the hot well controlled by a pH monitoring device
downstream of the well.
262
-------
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. This type of control
technology is presently being used by other plants in the
inorganic chemicals industry.
Non-Water Quality Environmental Impact
There appear to be no major non-water quality environmental
impacts or major energy requirements for the implementation
of the recommended treatment technologies.
BORAX (ORE MINING) Production Subcategory
Based on the information contained in Sections III through
VITI, a determination has been m^c that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of pollu^nts in process waste water.
Identification of BPCTCA
Best practicable control technology currently available for
the manufacture of borax from ore mining is containment of
process waste waters in percolation-proof evaporation ponds.
Reasons for Selection
The recommended technology is currently in use at an
existing plant.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory ac a whole would not have to invest
additionally to achieve limitations presc-ibed herein.
There is no anticipated increase in the operating costs.
All of this industry subcategory is presently achieving this
level of pollutant discharge.
Age and Size of Equipment and Facilities
The data obtained on the borax (ore mining) subcategory
represents a plant that is 16 years old.
The best control technology currently available is
practicable regardless of the size or age of plants since
the use of existing technologies is net dependent on these
factors.
263
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Process Employed
The general process employed in the borax (ore/mining) pro-
duction subcategory involves the mining, crushing, and dis-
solving of borax ore followed by the separation of the
product from the ore impurities.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in the borax (ore mining) production subcategory
because the ore deposits are located in the arid regions of
California and the existing plant utilizing this technology
accounts for over 70 percent of the total U.S. production of
borax. The remaining 30 percent is produced by Trona.
Process Changes
The recommended control technologies would not require any
changes in the manufacturing process.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category.
There appear to be no major energy requirements for the
implementation of the recommended treatment technologies.
BORIC ACID Production Subcateqory
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation -
Effluent Characteristic kg/metric ton(lbs/ton)
TSS 0.070 (0.1«)
arsenic 0.0014 (0.0028)'
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The above limitations were based on an average process
wastewater discharge of 2,800 liters per metric ton (673
gallons per ton) of product.
Identification of BPCICA
Best practicable control technology currently available for
the manufacture of boric acid by the acidulation of borax is
the reduction of the arsenic in the waste water by chemical
precipitation and coagulation followed by settling and
filtration to remove suspended solids generated by the
treatment.
To implement this technology at plants not already using the
recommended control techniques would require the segregation
of process waste waters, the installation of tanks for
chemical precipitation, coagulation and settling, and
filters to remove suspended solids.
Reason for selection
The boric acid plant studied produces over 70 percent of the
total boric acid production in the U.S. and presently has
plans to implement the recommended technologies. The
remainder is produced at Trona.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $80,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately 0.8 percent
of the selling price of this product.
Approximately 29 percent of this industry subcategory is
presently achieving this level of pollutant discharge.
Age and Sige of Equipment and Facilities
The data obtained on the boric acid (borax acidulation) sub-
category represents a plant that is approximately 50 years
old.
Process Employed
The general process employed in this production subcategory
involves the acidulation of borax with sulfuric acid.
Engineering Aspects
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From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in this production subcategory because the only
plant having a discharge plans to utilize these control
technologies.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by others in the inorganic
chemicals industry to reduce arsenic levels in process
wastewater.
Non-Water Qua litv Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the treated process waste waters. These
solids »ay sometimes contain harmful constituents which
could be detrimental to the soil system in the area of
disposal or possibly contaminate ground waters due to
rainwater runoff and percolation through the soil. Solid
waste disposal from inorganic chemical plants will be
considered by the EPA as a separate category. There appear
to be no major energy requirements for the implementation of
the recommended treatment technologies.
BROMINE Production Subcategory
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of pollutants in process waste water.
Identification of BPCTCA
There is no control technology needed for the manufacture of
bromine by brine well extraction. All process water and
spent brine is returned to the brine well.
CALCIUM CARBONATE Production Subcateqorv
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available for
the milk of lime process, is:
266
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Effluent Characteristic
TSS
Effluent Limitation -
kg/metric ton(Ibs/ton)
0.28 (0.56)
The above limitations were based on an overall average proc-
cess waste water discharge of 11,200 liters per metric ton
(2,690 gallons per ton) of product.
For the Solvay process, the degree of reduction based on the
best practicable control technology currently available is:
Effluent Characteristic
TSS
Effluent Limitation
kg/kkq (Ibs/ton)
0.58
(1.16)
The above limitation is based on an average process waste
water discharge of 23,400 liters per metric ton (5,600
gallons per ton) of product.
Identification of BPCTCA
Best practicable control technology currently available for
the manufacture of calcium carbonate by the carbonation of
lime or from the Solvay process wastes is good process water
management, the neutralization of process waste water and
settling of suspended solids before discharge.
To implement this technology at plants not already using the
recommended control techniques would require good process
water management including segregation, neutralization and
settling of suspended solids.
Reason for Selection
All three of the plants studied, accounting for over 90
percent of the U.S. production of precipitated calcium
carbonate, use portions of this treatment technology. One
plant that accounts for over one-third of the total
production is applying the recommended technology. The
effluent from this plant is a combined effluent from the
Solvay process complex and the apparent attributed wastes
are close to the guidelines. The treated effluent data
presented in Section V (3U mg/1 TSS for one plant and 25 to
30 mg/1 TSS for another plant with combined treatment of
several processes), indicates a need for improvement of
operation and/or design of the settling system in order to
meet the 1977 limitations.
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Total Cost of Application
Basea upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $150,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately 3 percent of
the selling price of this product.
Approximately 36 percent of this industry subcategory is
presently achieving this level of pollutant discharge.
Age and Size of Equipment and Facilities
The data obtained on the calcium carbonate subcategory
represents plants with ages ranging from 20 to U5 years and
production capacities ranging from about 100 to 200 metric
tons per day (110 to 220 tons per day).
The best control technology currently available is
practicable regardless of the size or age of plants since
the use of existing technologies is not dependent on these
factors. Also, the similarities in processes used and waste
water characteristics in this production subcategory
substantiate the practicality of these technologies.
Process Employed
The general processes employed in the calcium carbonate pro-
duction subcategory involve the carbonation of quicklime or
the reaction of waste streams from the Solvay process with
soda ash.
The processes used by the chemical plants in this
subcategory are very similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in this production subcategory because all three
of the major producers already have portions of the
treatment facilities required. Closer control of process
water quantities will have to be implemented.
Process Changes
268
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The recommended control technologies would not require major
changes in the manufacturing process. These control
technologies are presently being used by plants in this
production subcategory.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category.
There appear to be no major energy requirements for the
implementation of the recommended treatment technologies.
CALCIUM HYDROXIDE Production Subcategory
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of ef-
fluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of pollutants in process waste water.
Identification of BPCTCA
Best practicable control technology currently available for
the manufacture of calcium hydroxide by the lime slaking
process is the use of dry bag collection to control air
pollution.
To implement this technology at plants not already using the
recommended control techniques would require the
installation of dry bag collectors and associated duct work.
Reason for Selection
Dry bag collection techniques are presently being used
successfully throughout the U.S. in this production
subcategory as well as in other segments of the inorganic
chemicals industry.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
269
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to an estimated maximum of $150,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately 3.9 percent
of the selling price of this product.
Approximately 40 percent of this industry subcategory is
presently achieving this level of pollutant discharge.
Age and Size of Equipment and Facilities
The data obtained on the calcium hydroxide subcategory
represents plants with ages ranging from 17 to 20 years.
The best control technology currently available is
practicable regardless of the size or age of plants since
the use of existing technologies is not dependent on these
factors. Also, the similarities in processes used and the
lack of waste water in this production subcategory
substantiate the practicality of these technologies.
Process Employed
The general process employed in the calcium hydroxide pro-
duction subcategory involves the thermal decomposition of
limestone to quicklime followed by slaking of the quicklime
to the hydrate.
The processes used by the chemical plants in this subcate-
gory are very similar in nature and their raw wastes are
also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best control technology currently available is
practicable in the calcium hydroxide production subcategory
because it is a readily available and proven technology.
Process Changes
The recommended control technology would not require major
changes in the manufacturing process. This control tech-
nology is presently being used by plants in this production
subcategory.
Non-Water Quality Environmental Impact
270
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There appear to be no major non-water quality environmental
impacts or major energy requirements for the implementation
of the recommended treatment technology.
CARBON MONOXIDE and By-Product HYDROGEN Production
Subcateqorv
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of ef-
fluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation -
Effluent Characteristic kg/metric ton(lbs/ton)
TSS 0.06 (0.12)
COD 0.25 (0.50)
The above limitations were based on an average process
wastewater discharge of 6,150 liters per metric ton (1,480
gallons per ton) of product.
Identification of BPCTCA
Best practicable control technology currently available for
the manufacture of carbon monoxide and hydrogen by the re-
forming process is to collect all process waste water and
separate oil and grease before neutralization. Remove mono-
ethanolamine sludge from process waste water.
To implement this technology at plants not already using tne
recommended control techniques would require the installa-
tion of oil skimmers, neutralization tanks and collection
tanks for organic sludges.
Reason for Selection
One plant, accounting for over two-thirds of the total U.S.
production of carbon monoxide, is presently using the re-
commended technologies.
Total Cost of Application in Relation to Effluent Reduction
Benefits
Based upon the information contained in Section VIII of this
report, this subcategory would have to invest an additional
$14,000 to achieve the limitations prescribed herein. The
increased operating cost would be approximately 0.06 percent
of the selling price of this product.
271
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Age and Size of Equipment and Facilities
The data obtained on the carbon monoxide and by-product
hydrogen subcategory represents one plant that is
approximately 5 years old.
The best control technology currently available is practi-
cable regardless of the size or age of plants since the use
of existing technologies is not dependent on these factors.
Process Employed
The general process employed in this production subcategory
involves the reaction of methane, air and steam to form
carbon monoxide, hydrogen and carbon dioxide.
The processes used by the chemical plants in this subcate-
gory are very similar in nature and their raw wastes are
also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in the carbon monoxide and by-product hydrogen
production subcategory because most of the industry is
currently using the treatment technology.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in this produc-
tion subcategory.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of tne
environment is the potential effect of land disposal of the
sludges removed from the process waste waters. These
sludges may sometimes contain harmful constituents which
could be detrimental to the soil system in the area of
disposal or possibly contaminate ground waters due to
rainwater runoff and percolation through the soil. Solid
waste disposal from inorganic chemical plants will be
considered by the EPA as a separate category.
There appear to be no major energy requirements for the
implementation of the recommended treatment technologies.
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CHROME PIGMENTS AND IRON BLUES Production Subcategory
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of ef-
fluent reduction attainable through the application of the
best practicable control technology currently available is:
Cone. Effluent Limitation -
Effluent Characteristic Basis(mg/1) kg/metric ton(lbs/ton)
TSS 25 1.7 (3.4)
total chromium 0.5 0.034 (0.068)
chromium 6* 0.05 0.0034 (0.0068)
lead 2 0.14 (0.28)
zinc* 4 X(0.27) (X(0.54))
oxidizable cyanide** 0.05 0.0034 (0.0068)
total cyanide** 0.5 0.034 (0.068)
iron** 4 0.27 (0.54)
*Present only in complexes producing zinc yellow, X equals
zinc yellow fraction of inorganic pigment production at that
complex.
**Present only in complexes producing iron blues.
The above limitations were based on an average process
wastewater discharge of 67,000 liters per metric ton (16,100
gallons per ton) of product.
Identification of BPCTCA
Best practicable control technology currently available for
the manufacture of chrome pigments and iron blues by the
standard process is removal of metal ions by multistage
chemical precipitation and separation; and if cyanides are
present, oxidation of cyanide by alkaline chlorination or
biological digestion.
To implement this technology at plants not already using the
recommended control techniques would require the installa-
tion of the necessary treatment tanks, clarifiers, filters,
etc., to accomplish the reduction of pollutants in the dis-
charged process waste water.
Reason for Selection
At present, about 15 percent of the chrome pigment industry
is using the recommended technologies and by mid-1974 this
will increase to about 50 percent. The selected limitations
effectively control pollutants from this segment of the
273
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industry by efficient application of technologies now being
used.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $2,500,000 to achieve limitations
prescribed herein. There are additional costs amounting to
approximately two percent of the average selling price of
these products.
Age and Size of Equipment and Facilities
The data obtained on the chrome pigments and iron blues sub-
category represents plants with ages ranging from 25 to 58
years and production capabilities of similar magnitudes.
The best control technology currently available is
practicable regardless of the size or age of plants since
the use of existing technologies is not dependent on these
factors. Also, the similarities in processes used and waste
water characteristics in this production subcategory
substantiate the practicality of these technologies.
Processes Employed
The general processes employed in this production
subcategory are described in Section V of this report.
The processes used by the chemical plants in this
subcategory are very similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in the chrome pigments and iron blues production
subcategory because by mid-197H about one-haIf of the
production capacity of the industry will be utilizing these
technologies.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control
technologies are presently being used by plants in this
production subcategory.
274
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Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste 3isposal from
inorganic chemical plants will be considered by the EPA as a
separate category.
There appear to be no major energy requirements for the
implementation of the recommended treatment technologies.
CHROMIC ACID Production Subcategory
Based upon the information contained in Sections III through
VIII, a determination has been made that for chromic acid
produced in a plant with sodium dichromate, the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of pollutants in process waste water.
Identification of BPCTCA
There is no control technology needed for the manufacture of
chromic acid in plants also producing sodium dichromate.
Process wastes are attributable to the dichromate process
which has its own treatment facilities. The dichromate
effluent guidelines were covered elsewhere.
COPPER SULFATE (PURE_RAW MATERIAL) Production Subcateqorv
Based upon the information contained in Sections III through
VIII, a determination has been made fie* the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation
Effluent Charactertic kg/kkg (Ibs/ton)
Copper 0.0002(O.OOOU}
The above limitations are intended to control the carry-over
of pollutants into the barometric condenser water, even
though the available data does not indicate the presence of
copper salts.
Identification Qf_BPCTCA
275
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Best practicable control technology currently available for
the manufacture of copper sulfate using pure copper as a raw
material is total recycle of all process water including
spills and washdowns.
To implement this technology at plants not already using the
recommended control techniques would require the
construction of floor dikes, suitable plumbing and sumps,
and mother liquor recycle piping with associated pumping
equipment.
Reason for Selection
A copper sulfate plant presently uses this technology.
There is no discharge of pollutants in process waste water
at this facility which accounts for approximately 35 percent
of the U.S. production of copper sulfate by both methods.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, this subcategory would have to invest $10,000 to
achieve the limitations prescribed herein. The increase in
operating cost would be approximately 0.03 percent of the
selling price of this product.
Age and Size of Equipment and Facilities
The data obtained on the copper sulfate (pure raw material)
subcategory represents a plant that is approximately 53
years old.
The best control technology currently available is
practicable regardless of the size or age of plants since
the use of existing technologies is not dependent on these
factors. Also, the similarities in processes used and waste
water characteristics in this production subcategory
substantiate the practicality of these technologies.
Process Employed
The general process employed in the copper sulfate (pure raw
material) production subcategory involves the reaction of
pure copper metal with air, water and sulfuric acid.
The processes used by the chemical plants in this
subcategory are very similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
276
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Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best control technologa.es currently available is
practicable in the copper sulfate (pure raw material) pro-
duction subcategory because the technology exists and is
presently being used by a major producer.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech'
nologies are presently being used by plants in this produc -
tion subcategory.
Non- Water Quality Environmental Impact
There appear to be no major non-water quality environmental
impact or major energy requirements for the implementation
of the recommended treatment techologies.
COP PE_R_ SULFATE (RECOVERY PROCESS! Production Subcateqory
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation -
Effluent Characteristic kg/metric ton Jlbs/tgnj
TSS 0.023 (O.OU6)
copper 0.001 (0.002)
nickel 0.00? (0.004)
selenium 0.0005 (0.001)
The above limiLt, -cirt.'.o were1 basf-d on an average process
wast«water discharge of 930 liters per metric ton (220
gallons per ton) of product.
:MgI*±if icaticn af
Best practicable control technology currently available for
the manufacture of copper sulfate by the recovery process is
collection of waste mother liquor and process spills, wash-
downs, etc., and treatment with lime tc precipitate metal
ions followed by settling of suspended solids and
filtration.
277
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To implement this technology at plants not already using the
recommended control techniques would require the
installation of dykes, sewers, a treatment tank, a settling
tank and filter presses and associated equipment.
Reason for Selection
A major copper sulfate recovery process presently uses this
technology and is meeting the recommended effluent
limitations guidelines for copper, nickel and selenium.
Total suspended solids data were not obtained for this
subcategory, however, the available data for other
subcategories using similar treatment technology indicates
Sn ^h?r0peJiY desi?"ed and wel1 operated treatment system
can achieve the specified TSS limitation.
Total_CQgt of Application
Based upon the information contained in Section VIII of this
r^°ftf the Subcate9°ry as a whole would not have to invest
additionally to achieve limitations prescribed herein
Ninety percent of this industry subcategory is presently
achieving this level of pollutant discharge for the metal
parameters. Increase in the operating costs for that part
of the industry not achieving this level is less than 0 2
percent of the selling price of this product.
Age and Size of Equipment
The data obtained on the copper sulfate (recovery process)
subcategory represents a plant that is approximately 50
Ga
The best control technology currently available is practi-
cable regardless of the size or age of plants since the use
of existing technologies is not dependent on these factors.
Also, the similarities in processes used and waste water
characteristics in this production subcategory substantiate
the practicality of these technologies.
Process Employed
The general process employed in the copper sulfate (recovery
process) production subcategory involves the use of an
impure waste stream from a copper refinery as a raw material
along with additional copper metal, sulfuric acid, air and
water to form a solution of the product chemical The
processes used by the chemical plants in this subcategory
are very similar in nature and their raw wastes are also
278
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quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Asperi-s
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in this production subcategory because a major
plant, which accounts for approximately 35 percent of the
total U.S. production of copper sulfate by both methods,
presently uses this treatment technology.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process.
Non-Water Quality Environmental_Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal of
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category.
There appear to be no major energy requirements for the
implementation of the recommended treatment technologies.
FERRIC CHLORIDE Production Subcategory
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of pollutants in process waste water.
Identification of BPCTCA
Best practicable control technology currently available for
the manufacture of ferric chloride by the pickle liquor re-
covery process is to sump all sludges and process water
remove solids for landfill and recycle suoernatant liquor to
the process. " ^
To implement this technology at plants not already using the
recommended control techniques would require the
279
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installation of the necessary plumbing, sumps, solid-liquid
separators and recycle piping.
Reason for Selection
Of the three plants studied, which account for approximately
50 percent of the total U.S. production of ferric chloride,
two are presently on total recycle and the other is planning
to be on total recycle by the end of 1974. The recommended
BPCTCA. is the technology being used to achieve total recycle
of process water.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $60,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately 3.1 percent
of the selling price of this product.
Approximately 10 percent of this industry subcategory is
presently achieving this level of pollutant discharge.
Age and Size of Equipment and Facilities
The data obtained on the ferric chloride subcategory repre-
sents plants with ages ranging from 1 to 30 years and
production capacities ranging up to 75 metric tons per day
(83 tons per day) .
The best control technology currently available is practica-
ble regardless of the size or age of plants since the use of
existing technologies is not dependent on these factors.
Also, the similarities in processes used and waste water
characteristics in this production subcategory substantiate
the practicality of these technologies.
PjIQggss Employed
The general process employed in the ferric chloride
production subcategory involves the reaction of pickle
liquor with iron, chlorine and hydrochloric acid. The
sludges are landfilled and the solution of ferric chloride
is eitner sold as such or further processed to a dry
product.
The processes used by the chemical plants in this
subcateaory are very similar in nature and their raw wastes
280
-------
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in this production subcategory because the tech-
nology is an existing one, employed or contemplated by at
least half of the industry subcategory.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in this produc-
tion subcategory.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy
requirements for the implementation of the recommended
treatment technologies.
HYDROGEN (REFINERY BY-PRODUCT) Production^ ubcategory
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of pollutants in process waste water. There
are no waterborne pollutants generated by this process.
Identification of BPCTCA
There is no control technology needed for the manufacture of
hydrogen by the refinery by-product process. This is a
gaseous process which uses no water except for noncontact
cooling purposes. For hydrogen produced as a coproduct with
carbon monoxide, all wastes and treatment costs are totally
allocated to the carbon monoxide product.
281
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CYANIDE fACRYLQHITRILE BY-PRODUCTS Pro-action
Sabcateqory
Based upon the information contained in Sec^ons III through
Ifl, f determination has been made : net the degree of
effluent reduction attainable through thr application of the
best practicable control technology" cur-
-------
The two plants studied, accounting for approximately one-
half of the total U.S. captive and merchant production of
this chemical, are presently using portions of one or the
other methods of treatment technologies recommended.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $140,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately 0.2 percent
of the selling price of this product.
None of this industry subcategory is presently achieving
this level of pollutant discharge.
Age and Size of Equipment and Facilities
The data obtained on the hydrogen cyanide (Andrussow
process) subcategory represents two plants with similar ages
and production capacities.
The best control technology currently available is
practicable regardless of the size or age of plants since
the use of existing technologies is not dependent on these
factors. Also, the similarities in processes used and waste
water characteristics in this production subcategory
substantiate the practicality of these technologies.
Process Employed
The general process employed in the hydrogen cyanide
(Andrussow process) production sutcategory involves the
reaction of natural gas, ammonia and air.
The processes used by the chemical plants in this
subcategory are very similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Asjjectg
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in this production subcategory because the tech-
nologies exist and the important portions are in use in two
major plants.
Process Changes
283
-------
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in this produc-
tion subcategory.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy
requirements for the implementation of the recommended
treatment technologies.
IODINE Production Subcategory
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of
the best practicable control technology currently available
is no discharge of pollutants in process waste water.
Minimal costs of less than $1,000/year and 0.02 percent of
the selling price are needed for return of leaks and spills
to the brine cavity.
Identification of BPCTCA
There is no control technology needed for the manufacture of
iodine by the brine well extraction process. All process
water and spent brine are returned to the brine well.
IRON BLUES
See Chrome Pigments and Iron Blues.
LEAD MONOXIDE (LITHARGE) Production Subcategory
Based upon the information contained in Sections III through
VTII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of pollutants in process waste water.
Identification of BPCTCA
284
-------
Best practicable control technology currently available for
the manufacture of lead monoxide by the standard process is
to use dry vacuuming to pick up lead oxide spills or dust.
In the event washdown water is used, this water should be
impounded to settle out suspended solids and reused as wash-
down water.
To implement this technology at plants not already using the
recommended control techniques would require the segregation
of washdown water from other plant complex water flows,
installation of a suitable sump, and water circulating
pumps.
Reasons for Selection
Dry vacuuming of lead oxide dust is presently being done.
Since no water is used in the process, other than noncontact
cooling water, there is no discharge of pollutants. In
plants where washdown is used to clean up product dust, the
recommended segregation of wash water and its reuse after
removal of suspended solids would also result in no
discharge of pollutants.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $230,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately 0. 1 percent
of the selling price of this product.
Approximately 83 percent of this industry subcategory is
presently achieving this level of pollutant discharge.
Age and Size of Equipment and Facilities
The data obtained on the lead monoxide subcategory
represents two plants with ages ranging up to 95 years and
production capacities in a ratio of about 4 to 1.
The best control technology currently available is
practicable regardless of the size or age of plants since
the use of existing technologies is not dependent on these
factors. Also, the similarities in processes used and waste
water characteristics in this production subcategory
substantiate the practicality of these technologies.
Process Employed
285
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The general process employed in the lead monoxide production
subcategory involves the oxidation of molten lead in
furnaces. There is no water, other than noncontact cooling
water, used in the process.
The processes used by the chemical plants in this
subcategory are very similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in the lead monoxide production subcategory be-
cause the majority of plants producing lead monoxide are
presently using the recommended treatment technologies and
are not discharging process water containing pollutants to
navigable waters.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in this produc-
tion subcategory.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect cf land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy
requirements for the implementation of the recommended
treatment technologies.
LITHIUM CARBONATE (SPODUMENE ORE) Production Sufccateqory
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation -
Effluent Characteristic kg/metric ton (Ibs/ton)
286
-------
TSS
0.9
(1-8)
The above limitations were based on an average process
wastewater discharge of 36,000 liters per metric ton (8,600
gallons per ton) of product.
Identification of BPCTCA
Best practicable control technology currently available for
the manufacture of lithium carbonate by spodumene ore
extraction is neutralization of all process water followed
by settling to reduce suspended solids in the plant
effluent.
Reason for Selection
There is only one plant using this process and it is
presently using this treatment technology. Total suspended
solids data were not obtained for this subcategory, however,
the available data for other subcategories using similar
treatment technology indicates that a properly designed and
well operated treatment system can achieve the specified TSS
limitations,
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would not have to invest
additionally to achieve limitations prescribed herein.
There would be no anticipated increase in the operating
cost.
Age and Size of Equipment and Facilities
The data obtained on the lithium carbonate (spodumene ore)
subcategory represents one plant that is 19 years old.
The best control technology currently available is practi-
cable regardless of the size or age of plants since the use
of existing technologies is not dependent on these factors.
Process Employed
The general process employed in the lithium carbonate
(spodumene ore) production subcategory involves the reaction
of sulfuric acid with spodumene ore followed by reaction
with soda ash.
Process Changes
287
-------
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by the only plant in this
production subcategory.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by EPA as a
separate category.
There appear to be no major energy requirements for the
implementation of the recommended treatment technologies.
NICKEL SULFATE Production Subcategory
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of ef-
fluent reduction attainable through the application of the
best practicable control technology currently available is:
No discharge of pollutants in process waste water when
process employs pure raw materials. When plating solutions
are used as raw materials in the process:
Effluent Characteristic
TSS
nickel
Effluent Limitation -
kg/metric ton (Ibs/ton)
0.032
0.002
(0.064)
(O.OOU)
The above limitations were based on an average process
wastewater discharge of 1,170 liters per metric ton (280
gallons per ton) of product.
Identification of BPCTCA
Best practicable control technology currently available for
the manufacture of nickel sulfate using pure raw materials
is recycle of all process water. When the process employs
impure plating solution as the raw material the BPCTCA is
treatment of process waste water with caustic to precipitate
nickel followed by sand filtration to remove suspended
solids. The basis for the nickel guidelines is 2 mg/1 which
requires an improvement over the present treated effluent of
288
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3 mg/1. However, it should be noted that a similar
treatment scheme is utilized within the copper sulfate
production industry to achieve a treated nickel
concentration of 0.5 mg/1.
To implement this technology at plants not already using the
recommended control techniques would require the
installation of caustic treatment tanks and associated
plumbing, sand filtration equipment and pH control
equipment.
Reason for Selection
This technology is presently used at one plant accounting
for over 40 percent of the total U.S. production of nickel
sulfate and is believed to be in use at another similar size-
facility.
Total Cost of Application
Based upon tne information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $10,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately 0.1 percent
of the selling price of this product.
Approximately 85 percent of this industry subcategory is
presently acnieving this level of pollutant discharge,
Age and Size of Equipment and Facilities
The data obtained on the nickel sulfate subcategory repre-
sented plants with similar ages.
The best control technology currently available is practi-
cable regardless of the size or age of plants since the use
of existing technologies is not dependent on these factors.
Also, the similarities in processes used and waste water
characteristics in this production subcategory substantiate
the practicality of these technologies.
Process Employed
The general processes employed in the nickel sulfate
production subcategory involve the reaction of either pure
nickel-containing raw materials or impure nickel-containing
raw materials such as spent plating solutions with sulfuric
acid. The processes used by the chemical plants in this
subcategory are very similar in nature and their raw wastes
289
-------
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in the nickel sulfate production subcategory
because at least one plant accounting for over UO percent of
the total U.S. production of this chemical is presently
using the technologies recommended.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in this
production subcategory.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. However, most solids generated by this
process are usually recovered for their nickel values.
There appear to be no major energy requirements for the
implementation of the recommended treatment technologies.
NITROGEN AND OXYGEN Production_SubcategQry
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of ef-
fluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation -
Effluent Characteristic kg/metric ton (Ibs/ton)
Oil and Grease 0.001 (0.002)
The above limitations were based on an average process waste
water discharge of 39 liters per metric ton (9.3 gallons per
ton) of oroduct.
290
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Identification QjL_ BPCTCA
Best practicable control technology currently available for
the manufacture of nitrogen and oxygen by the air reduction
process is isolation of oil-containing water and separation
of oil before release.
Reason for Selection
Separation of oil from the process wastes is practicable for
this pollutant and is consistent with the practices of the
plants studied.
_cgst_of _Ap_p_lication
Baaed upon the information contained in Section VIII of this
report, t he subcategory as a whole would have to invest up
i-o .in estimated maximum of $600,000 to achieve limitations
prr-tcribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately O.U percent
of the soiling price of this product.
The data obtained on the nitrogen and oxygen subcategory
represents plants with ages ranging from 5 to 31 years and
production capacities ranging from 450 to 700 metric tons
per day (500 to 770 tons per day) of combined product.
The best control technology currently available is practi-
cable regardless of the size or age of plants since the use
of existing technologies is not dependent on these factors.
Also, the similarities in processes used and waste water
characteristics in this production subcategory substantiate
t h" prnc-t ieal ity ot these technologies.
The general process employed in the nitrogen and oxygen
production cubcategory involves the liguefaction and distil-
lation ot air.
The processor used by the chemical plants in this subcate-
gory are very similar in nature and their raw wastes are
also guite similar. These similarities will enhance the
application of the recommended treatment technologies.
291
-------
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in the nitrogen and oxygen production sub-
category because it has been demonstrated that oil removal
and disposal can be accomplished with minimal cost.
The recommended contx r I technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by olants in this
production sutr.i'.e j-jry,
.- Water _£ual it _£ J>j[i rjfnm^ntaj^. Impact
appear to be ro ;i,ajor non-water quality environmental
or major wrov requirement 3 tor the implementation
ot the recommended t,/; -a at: Tent technologies.
Based upon the inf ,>c inahion contained in Sections III through
VIII, a determination has been made that the degree of ef-
fluent reduction <*tt. suable through the application of the
best practicable control technology currently available is
no discharge of pDiJutanto in process waste water.
Pollutants dfc£iii,tri for this production subcategory are
suspended solids.
There is no ccn*r<-.t technology needed for the manufacture of
potassium ch3ori.1e f..o»ft Sylvite ore. This production sub-
category is located j.,- an area close to the ore deposits and
the locale ia conducive to the disposal of process wastes to
surface evaporation. iround water contamination is not a
problem since the beat, ground water, in the area of the
plants, already contains a high concentration of sodium
chloride.
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of ef-
fluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation -
j£g/?Betr ic_ ton (Ibs/ton)
292
-------
T8S 0,03 (0.06)
barium 0.003 (0.006)
iron 0.005 (0.01)
sulfide 0.005 (0.01)
The above limitations were based on an average process
wastewater discharge of 1,200 liters per metric ton (290
gallons per ton) of product.
Best practicable control technology currently available for
the manufacture of potassium iodide by either process is to
collect all process waste water and precipitate heavy metals
as the sulfide and barium as the sulfate followed by
settling and clarification. For the process which generates
iodate ion as a waste, treatment with excess thiosulfate is
recommended to reduce the iodate ion to iodide.
Rea s_Qn f or Se jlect ion
Neither plant employs any treatment technology for their
wastes. One plant does not have to because of its
geographical location. All waste water is evaporated. The
effluent limitations guidelines are for the other plant and
are based on solubility limits of the various precipitated
impurities in the waste water.
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $3,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
operating cost equivalent to approximately 0.07 percent of
the 1971 selling price of this product.
Approximately 33 percent of this industry subcategory is
presently achieving at least this level of pollutant
discharge.
Age and Size of Equipment and Facilities
The data obtained on the potassium iodide subcategory repre-
sents plants with ages ranging from about 20 to 12 years.
The best control tachnology currently available is practi-
cable regardless of the size or age of plants since the use
of existing technologies is not dependent on these factors.
Also, the similarities in processes used and waste water
293
-------
characteristics in this production subcategory substantiate
the practicality of these technologies.
Process Employed
The process employed in the potassium iodide production sub-
category involves the reaction of iodine with water and
potassium hydroxide.
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in the potassium iodide production subcategory
because one plant already has no discharge of pollutants in
process water because of its geographical location. There-
fore, only one plant in the production subcategory needs to
install the necessary treatment facilities.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by other plants in the in-
organic chemicals industry.
Non-Water^Suality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy
requirements for the implementation of the recommended
treatment technologies.
SILVER^ NITRAT E Product ion Subcat eqory
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation -
Effluent Characteristic kg/metric ton fibs/ton}
294
-------
TSS 0.023 (0.046)
silver 0.003 f 0.006)
The above limitations /;oi.; oaseci on an. average process
wastewater discharge of 1,500 liters per metric ton (350
gallons per ton) of r.ro.-lnc-t „
if iC iono i
Best practicable contvsS ! <--r:•'.»; ;j;,> ;;roce-':5 w^r-t^r, through a
silver T <•=<.. --'•*.•-.- i';* a at .-ai I-')'.-: r..1 hy trick?. Ina filters in
r^ri-:^ >-in and cl arif ics
One planrr arcotinhir- - •" ,v o'/f---; f>0 percent of the total U.S.
production of "ilvr-r nitrv>t--., is presenMy using this
"
rss ti^^jr?: * *".'• 7 itn •"> I n c.- Trained in Section VIII of this
report, ^h^ nnhc-t* '---lorv ,j-3 o whole would have to invest up
to an est-.im.-ti: «->'."; maxi^m;. >-f $K!,-,()0'1 to achieve limitations
presrrihod l;^r^i ?K Thf-t •:> is also an anticipated increase in
the oprr. -\i-ir.-j *-,5i-t .-'.-si> v.*j i>ni. ho approximately 0.11 percent
of th«* M«*A li»f,t uricr of i-rsin
Approxim,^«.l y ?> '• o^-i .-«.-».»- .,-i thin indu-s-ry suhcateqory is
1y .-v-»n«vir\.v thi= lr-,/r.]. Of pollutant dif? charge.
3 nd _Hi z < * _, ot. _ Fy u x p 51 *> s •-_ L _ 5«i d__ £' 'a c i j,. i jt ie n
The data ohtaimrl .-HI ^hs sU Ivor nitrate suhcategory
reprer;enj:s- plant: H wit)! /, •<" t,-. -; ! ?. t -yge*j,
The hfsst. control t.-::i-ir,olcviy currently available is
practicahlo r^octrdlosw of the size or age of plants since
tho u~' of^^xir?.in.5f t.---1-.f..ilo7Les is not dependent, on these
factor;-:, At^o, tho -:.:'> I. rfiriesi in processes used and waste
water characteristic-. in this production subcateaory
substantiate th^> practicality ot theso technologies.
-------
The general process employed in the silver nitrate
production subcatagory involves the reaction of pure silver
with distilled nitric acid.
Tno procrsi.es is rd -y tne chemical plants in this
subcategory are ver/ -similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
appli.cat3.on of the reo:.:i..r.=nded treatment technologies.
Froas an engineer Ir.a ^*,,»uapoi'tt , the implementation of the
recommended U-..-,t cor:^,j.i technologies currently available is
practicable m t,h€ -.liver nitrate production subcategory be-
aetion subcategory presently uses the
cause rv.%st, of tt,
The r«*corv.,en
-------
Best practicable control technology currently available for
the manufacture of sodium fluoride by the anhydrous?
neutralisation process is complete recycle of all process
water.
Best practicable control technology currently available for
the manufacture of sodium fluoride by the sodium silico-
fluoride process is to pond and totally recycle all waste-
waters.
To implement this technology at plants not already using the
recommend od : ntrol techniques would require construction of
adequate pcadts to held normal rainwaters and process waters
from siiicoiiaorivle process plants.
Reason ..for_. Se 1 ecti on
Only ori'3 plant is using the anhydrous neutralization process
in the U.3, and it totally recycles process water with no
discn&rce cf waterborne pollutants.
Only ^;'"if ^ant in the U.S. if, using the sodium
silicc«£l",iu^ Irte process and the complex it is in has a
favorable wav-ei balance for using the recycle waters.
To t a 1 _Cot?t
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $10,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately 0.1 percent
of the selling price of this product.
Approximately 57 percent of this industry subcategory is
presently achieving this level of pollutant discharge.
Age and Size of Equipment and Facilities
The best control technology currently available is
practicable regardless of the size or age of plants since
the use of existing technologies is not dependent on these
factors,
Process Employed
The general processes employed in this production
subcategory involves:
1) the reaction of anhydrous hydrogen fluoride with soda
-------
ash, or
2) the reaction of sodium silicofluoride with caustic soda
solution.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in this production subcategory because the
existing plant practicing the sodium silicofluoride process
is in a complex having a favorable water balance for total
recycle by this process.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing processes.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of dispoal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy
requirements for the implementation of the recommended
treatment technologies.
SODIUM SILICOFLUORIDE Production Subcategorv
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation -
Effluent Characteristic kg/metric ton (Ibs/tonl
TSS 0.3 (0.6)
fluoride 0.25 (0.5)
The above limitations were based on an average process
wastewater discharge of 12,500 liters per metric ton (3,000
gallons per ton) of product.
Identification of BPCTCA
298
-------
Best practicable control technology currently available for
the manufacture of sodium silicof luoride is to treat all
process waste water with lime and settle the suspended
solids before discharge.
£_c>r__.£. elect ton
The recommended technologies are the industry standard to
reduce fluoride and suspended solids in process waste water.
All of the production subcategory not using deep well
disposal eapl ,v.-;. these technologies.
Base-i upon thfc Information contained in Section VIII of this
report, the subcategory as a whole would not require an
appreciable additional investment: to achieve limitations
presented herein. There is also no anticipated increase in
the operating co?t«
Ail of tiiio inunctry aubcategory is presently achieving this
level of pelli.ra^f, discharge.
. Facilities
The data obtained on the sodium silicof luoride subcategory
represents plants with ages ranging from 16 to 36 years and
production capacities with a seven-fold range.
The best .-ontrol technology currently available is
practicable regardless of the size or age of plants since
the use of existing technologies is not dependent on these
tactors. Also, the similarities in processes used and waste
water characteristics in this production subcategory
substantiate the practicality of these technologies.
Process Employjed
The general process employed in the sodium silicof luoride
production subcategory involves the reaction of fluosilicic
acid with sodiatn chloride or soda ash.
The processes used by the chemical plants in this
subcategory are very similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Enq i neer ing_A
299
-------
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in the sodium silicofluoride production
subcateqory because all the plants in the subcategory
discharging process water are already using the
technologyen.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. The control
technologies are presently being used by plants in this
production subcategory,
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy
requirements for the implementation of the recommended
treatment technologies.
, FPQCSSS)
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of pollutants in process waste water.
There is no control technology necessary for the manufacture
of stannic oxide by the dry process.
No process water is used and therefore no water borne wastes
are generated. About half of the U.S. production of stannic
oxide is made at one plant by this process.
gTANNIC__gXIDE_iWET_^RQCESgi Production SubcategorY
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
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effluent reduction attainable through the application of the
best practicable control technology currently available is:
Effluent Limitation -
Effluent Characteristic kg/metric ton^ (lbs/ton]|
TSS 1.6 (9.2)
The above limitations were based on an average process
wastewater discharge of 185,300 liters per metric ton
(44,000 gallons per ton) of product.
Identification of BPCTCA
Best practicable control technology currently available for
the manufacture of stannic oxide by the wet process is
treatment to break the oil emulsion, flotation, filtration,
and carbon absorption or activated sludge treatment.
Reason for Selection
The selection of BPCTCA was based on the standard method of
reducing organics and suspended solids in a waste stream.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $120,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately 3.2 percent
of the selling price of this product.
None of this industry subcategory is presently achieving
this level of pollutant discharge.
Age and Size of Equipment and Facilities
The data obtained on the stannic oxide (wet process)
subcategory represents the only plant in the production
subcategory. Therefore, these criteria are not applicable.
Process Employed
The general process employed in this production subcategory
is proprietary.
Engineering Aspects
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From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in the stannic oxide (wet process) production
subcategory because there is only one plant using this pro-
cess and is presently discharging into a municipal sewer.
Process Changes
This plant plans a process change which will eliminate
organics from the waste stream and lower the hydraulic load.
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
organic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy
requirements for the implementation of the recommended
treatment technologies.
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available is
no discharge of pollutants in process waste water. Possible
pollutants generated in the manufacture of borax,, boric
acid, bromine, lithium carbonate and potassium chloride by
the Trona process are suspended solids, BOD, COD, organics
and arsenic.
Identification of BPCT^R
There is no control technology needed for the manufacture of
borax, boric acid, bromine, lithium carbonate and potassium
chloride by the Trona process. All process water and spent
brine is returned to Searles Lake to maintain brine levels.
The process is specific to this region and discharges only
to the source.
.ZINC_SULFATE Pro duct in
Based upon the information contained in Sections III through
VIII, a determination has been made that the degree of
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effluent reduction attainable through the application of the
bast practicable control technology currently available is
no discharge of pollutants in process waste water.
Identification of BPCTCA
Best practicable control technology currently available for
the manufacture of zinc sulfate is total recycle of all
process water.
T . implement this technology at plants not already using the
a ,. ommended control techniques would require the
installation of suitable pumps and piping.
F£ 1 s,on_ tor_ S e 1 ect_i on
Tbn>-Me of the four plants studied are presently on total re-
cycle of process water. The fourth plant has to recycle its
wet scrubber wastes and to recycle its raw material cleanup
•.-.-ft-.tes back to the hydrosulfite process to achieve total re-
rv~!.e. These four plants account for approximately 90
i.-accent of the total U,S. production of zinc sulfate.
Tota1^Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $60,000 to achieve limitations
prescribed herein. Anticipated increase in the operating
cost is 0,,'U percent.
Approximately 66 percent of this industry subcategory is
presently achieving this level of pollutants discharge.
Age and Size_gf_S3ui2ffl§St_§nd_£ac_ilities
The data obtained on the zinc sulfate subcategory represents
plants with ages ranging from 13 to 50 years and production
capacities having a three-fold range.
The best control technology currently available is
practicable regardless of the size or age of plants since
the use of existing technologies is not dependent on these
factors. Also, the similarities in processes used and waste
water characteristics in this production subcategory
substantiate the practicality of these technologies.
.E mployed
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The general process employed in the zinc sulfate production
subcategory involves the reaction of sulfuric acid with
various crude zinc starting materials such as crude zinc
oxide, zinc metal residues and crude zinc carbonate by-
product from sodium hydrosulfite manufacture.
The processes used by the chemical plants in this
subcategory are very similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best control technologies currently available is
practicable in the zinc sulfate production subcategory be-
cause the plants already on total recycle account for over
one-half of the total U.S. production.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in this produc-
tion subcategory.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy
requirements for the implementation of the recommended
treatment technologies.
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SECTION X
EFFLUENT SEDUCTION ATTAINABLE THROUGH THE
APPLICATION OF THE BEST AVAILABLE
TECHNOLOGY ECONOMICALLY ACHIEVABLE
The effluent limitations which must be achieved by July 1,
1983 are based on the degree of effluent reduction attain-
able through the application of the best available
technology economically achievable. For the inorganic
chemical industry, this level of technology was based on the
very best control and treatment technology employed by a
specific point source within each of the industry's
subcategories, or where it is readily transferable from one
industry process to another. Each chemical subcategory will
be treated separately for the recommendation of effluent
limitations guidelines and standards of performance.
The following factors were taken into consideration in
determining the best available technology economically
achievable:
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 application of BATEA; and
f. non-water quality environmental impact (including
energy requirements).
In contrast to the best practicable technology currently
available, best available technology economically achievable
assesses the availability in all cases of in-process
controls as well as control or additional treatment
techniques employed at the end of a production process. In-
process control options available which were considered in
establishing these control and treatment technologies
include the following:
a. alternative water uses
b. water conservation
c. waste stream segregation
d. water reuse
e. cascading water uses
f. by-product recovery
g. reuse of waste water constituents
h. waste treatment
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i. good housekeeping
j, preventive maintenance
k. quality control (raw material, product, effluent)
1. monitoring and alarm systems.
Those plant processes and control technologies which at the
pilot plant, semi-works, or other level, have demonstrated
both technological performances and economic viability at a
level sufficient to reasonably justify investing in such
facilities were also considered in assessing the best avail-
able technology economically achievable. It has been demon-
strated to be capable of being designed for plant scale
operation up to and including "no discharge" of pollutants.
Although economic factors are considered in this
development, the costs for this level of control are
intended to be for the top-of-the-line of current technology
subject to limitations imposed by economic and engineering
feasibility. However, this technology may necessitate some
industrially sponsored development work prior to its
application.
Based upon the information contained in Sections III through
IX of this report, the following determinations were made on
the degree of effluent reduction attainable with the
application of the best available control technology
economically achievable in the various subcategories of the
inorganic chemical .industry.
GENERAL WATER
Process water is defined as any water contacting the react-
ants, intermediate products, by-products or products of a
process including contact cooling water. All values of
guidelines and limitations presented below are expressed as
§ maximum monthly ayj-rage in units, of. kilograms of pollutant
per metric ton of product (pounds of pollutant per ton of.
productL produced. The daily maximum limitation is double
the monthly average:„ except as noted. All process water
effluents are limited to~the pH range of 6.0 to 9^0 unless
otherwise specified.
In the chemical industry, cooling and process waters are
sometimes mixed prior to treatment and discharge. In other
situations, only cooling water is discharged. Based on the
application of best available technology economically
achievable, the recommendations for the discharge of such
cooling water are as follows.
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An allowed discharge of all. noncontact cooling waters pro-
vided that the following conditions are met:
a) Thermal pollution be in accordance with standards to be
set by EPA policies. Excessive thermal rise in once
through noncontact cooling water in the inorganic
chemical industry has not been a significant problem.
b) Ail noncontact cooling waters should be monitored to
detect leaks from the process. Provisions should be made
for treatment to the standards established for the process
v-\ste water discharges prior to release,
c) Kc- untreated process waters be added to the cooling waters
p.-:ior to discharge.
The above noncontact cooling water recpmmendations shouId be
£9Jl§.id§£§£l §.§. iQferJEiffif since this type of water plus blow-
downs from water treatment, boilers and cooling towers will
be regvilated by EPA at a later date as a separate category.
PAQ£ES^WA^TEjjATER_GUIDELINES_AND LIMITATIONS FOR J?HE
SIGNIFICANT,JLNgRGANIC_CHEMICALS_PQINT SOURCE SUBCATEGORIES
The following industry subcategories were required to
achieve no discharge of process waste water pollutants to
navigable waters based on best practicable control
technology currently available:
Ammonium chloride (anhydrous ammonia and hydrogen chloride
gas process)„ borax (ore-mined borax and Trona process),
boric acid (Trona process)„ Bromine (brine-mining and Trona
process), calcium hydroxide, chromic acid, ferric chloride,
hydrogen, hydrogen cyanide (acrylonitrile by-product),
iodine,, lead monoxide (litharge) , lithium carbonate (Trona
process), potassium chloride (mining and Trona processes),
sodium fluoride, stannic oxide (dry process) and zinc
sulfate.
The same limitations guidelines are required based on best
available technology economically achievable.
The 1983 guideline basis for total suspended solids is a
properly designed and well operated treatment system
achieving 15 mg/1 TSS using settling or clarification and 10
mg/1 with added filtration systems. As discussed in Section
IX, the same technology formed the guideline basis for the
1977 limitations, but did not require optimization of
process discharges and treatment operation until 1983 in
3C7
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order to determine the optimum operating conditions and to
train skilled operators.
ALUMINUM FLUORIDE Production Subeateqory
Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available control technology economically achievable
is:
Effluent Limitation -
Ef f luent_Cha^§cterisr.i<7
Fluoride 0.034 (0.068)
TSS 0.026 (0.052)
Aluminum tl.017 (o.o34)
I de n ti f icat i on_jof__BATgA
Best available technology economically achievable for the
manufacture of aluminum fluoride by the hydrated
alumina-hydrogen fluoride process is lime treatment of the
scrubber water followed by removal of the precipitated
materials and recycle of r.hese waters to the scrubber.
To implement this technology ^t plants not already using the
recommended control techniques would require the
installation of the necessary piping and pumps to recycle
the scrubber water.
The effluent limitations provide for a ten percent blowdown
from the recycled scrubber water (1,700 1/kkg or 410 gal/ton
of product}„ This allows dilution of the recycled scrubber
water to ai'oid potential saturation concentrations and
possible plugging of scrubbers.
Reason for Selection.
The recommended technology is presently being used elsewhere
in the inorganic chemical industry for the recycle of
treated fluoride-containing process water.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $2,300,000 to achieve limitations
prescribed herein, There is also an anticipated increase in
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the operating cost equivalent to approximately 1.2 percent
of the selling price of this product.
Approximately 25 percent of this industry subcategory is
presently achieving this level of pollutant discharge.
Aae flfld Size of Equipment and Fa9iJti^jes
The data obtained on the aluminum fluoride subcategory
represents plants with ages ranging from 8 to 11 years and
similar production capacities.
The best available technology is economically achievable
regardless of the size or age of plants since the use of
existing technologies is not dependent on these factors.
Also, the similarities in processes used and waste water
characteristics in this production subcategory substantiate
the practicality of these technologies.
The processes used by the chemical plants in this
subcategory are v»ry similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
Prom an engineering standpoint, the implementation of the
recommended best available technology is economically
achievable in the aluminum fluoride production subcategory
because two of three known plants are already achieving the
recommended effluent guidelines by various means. The use
of recycle technology and equipment is readily available in
the industry.
Process Ghanaqg
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in other
production subcategories.
I39J3rHateiL.QuajJ.tyL Environmental Imoac^
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
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inorganic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy
requirements for the implementation of the recommended
treatment technologies.
Aja}OljIUM_CHLORlpE_PrQduct Ion Subcategory
Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best practicable control technology currently available for
ammonium chloride recovery from sodium carbonate is no
discharge of process waste water pollutants to navigable
waters.
8«st available technology economically achievable for the
manufacture of ammonium chloride as a by-product of tho
Solvay process includes replacement of all barometric
condensers with noncontact condensers.
Ammonium chloride production by the reaction of anhydrous
ammonia with hydrogen chloride gas is a no discharge process
as described in Section IX. Ammonium chloride production by
the reaction of aqueous hydrogen chloride and ammonia is not
covered in this study.
To implement this technology at plants not already using the
recommended control techniques would require the
installation of noncontact condensers (Solvay by-product
only) .
Replacing the barometric condensers with noncontact
condensers eliminates the source of contamination of the
effluent.
IS&aL-Co2t_oi_AjDp_l 4sation
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $35,000 to achieve the
limitations prescribed herein.
&gg-and_slze_of_SgvjiBment and Facilities
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The above limitations were based on an average process
wastewater discharge of 2,800 liters per metric ton (673
gallons per ton) of product.
Identification of BATEA
Best available technology economically achievable for the
manufacture of boric acid by the acidulation of borax
process is identical to best practicable control technology,
i.e., the reduction of arsenic in the process waste water by
chemical precipitation and coagulation followed by settling
and filtration to remove suspended solids generated.
To implement this technology at plants not already using the
recommended control techniques would require the segregation
of process waste waters, the installation of tanks for
chemical precipitation, coagulation and settling, and
filtration to remove suspended solids.
Reason for Selection
One plant producing over 70 percent of the total boric acid
production is planning to implement the recommended technol-
ogies. The remainder of boric acid production occurs at
Trona.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would not require an
appreciable additional investment to achieve the limitations
prescribed herein.
Age and Size of Equipment and Facilities
The data obtained on the boric acid (borax acidulation) sub-
category represents a plant approximately 50 years old.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best available technologies is economically
achievable in the boric acid (borax acidulation) production
subcategory because the major producer (over 70 percent)
plans to implement these treatment technologies.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
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nologies are presently being used by plants in other produc-
tion subcategories.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the treated process waste waters. These
solids may sometimes contain harmful constituents which
could be detrimental to the soil system in the area of
disposal or possibly contaminate ground waters due to
rainwater runoff and percolation through the soil. Solid
waste disposal from inorganic chemical plants will be
considered by the EPA as a separate category. There appear
to be no major energy requirements for the implementation of
the recommended treatment technologies.
CALCIUM CARBONATE Production Subcategory
Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable for the
milk of lime process is:
Effluent Characteristic
TSS
Effluent Limitation -
kg /metric ton (Ibs/ton)
0.11
(0.22)
The above limitations were based on an overall average
process waste water discharge of 11, 200 liters per metric
ton (2,690 gallons per ton) of product.
For the Solvay process, the degree of reduction based on the
best available technology economically achievable is:
Effluent Characteristic
TSS
Effluent Limitation -
kg /metric ton
0.23
(O.U6)
The above limitations were based on an average process waste
water discharge of 23,400 liters per metric ton (5,600
gallons per ton) of product.
Identification of BATEA
Best available technology economically achievable for the
manufacture of calcium carbonate by the carbonation of lime
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or from the Solvay process wastes is good process water man-
agement, the neutralization of process waste water, settling
of suspended solids followed by polish filtration.
To implement this technology at plants not already using the
recommended control techniques would require good process
water management including segregation, neutralization,
settling, and polish filtration.
Reason for Selection
All three of the plants studied are presently using portions
of this treatment technology and the other technology is
being used in other portions of the inorganic chemical
industry. The apparent attributed wastes from the Solvay
waste product process from one plant are within the
guidelines.
Cost of Application
Based upon the information contained in Section VIII of this
report, the subcateqory as a whole would have to invest up
to an estimated maximum of $980,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately 8.0 percent
of the selling price of this product.
None of this industry subcategory is presently achieving
this level of pollutant discharge.
Age and Size of Equipment and Facilities
The data obtained on the calcium carbonate subcategory
represents plants with ages ranging from 20 to 45 years and
production capacities ranging from about 100 to 200 metric
tons per day (110 to 220 tons per day).
The best available technology economically achievable is
practicable regardless of the size or age of plants since
the use of existing technologies is not dependent on these
factors. Also, the similarities in processes used and
wastewater characteristics in this production subcategory
substantiate the practicality of these technologies.
The processes used by the chemical plants in this subcate-
gory are similar in nature and their raw wastes are also
quite similar. These similarities will enhance the applica-
tion of the recommended treatment technologies.
Engineering Aspects
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From an engineering standpoint, the implementation of the
recommended best available technologies is economically
achievable in the calcium carbonate production subcategory
because all three of the major producers already have por-
tions of the treatment facilities installed. The remaining
portions of the treatment facilities are practiced widely in
the inorganic chemical industry.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in this
production subcategory.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy re-
quirements for the implementation of the recommended treat-
ment technologies.
CARBQN^MQNQXIDE AND BY-PRODUCT HYDROGEN Production
Subcateqory
Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is:
Effluent Limitation -
Effluent Characteristic kg/metric ton fibs/ton)
COD 0.065 (0.13)
TSS 0.017 (0.03U)
The above limitations were based on an average process
wastewater discharge of 1,130 liters per metric ton (270
gallons per ton) of product.
Identification of BATEA
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Best available technology economically achievable for the
manufacture of carbon monoxide and by-product hydrogen by
the reforming process is to isolate, collect and separate
oil and grease prior to mixing with other waste water.
Segregate the process wastewater from the boiler blowdown,
water treatment, cooling tower, and sanitary wastes. The
wastewater is then neutralized. The process water
containing monoethanolamine sludges is isolated, contained
and disposed of.
To implement this technology at plants not already using the
recommended control techniques would require the installa-
tion of oil and grease segregation facilities,
neutralization tanks and collection tanks for organic
sludges.
Reason for Selection
Most of the technologies described are currently in use at
one of the major (over 66 percent) U.S. producers. The
remaining technology is well known and being used in other
portions of the inorganic chemical industry.
Tgta.L_Cgsjt__gf Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $61,000 over that required for
best practicable control technology to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately 0. 1 percent
of the selling price of this product.
Age and Size of Equipment and Facilities
The data obtained on the carbon monoxide and hydrogen by-
product subcategory represents one plant five years old.
The best available technology economically achievable is
practicable regardless of the size or age of plants since
the use of existing technologies is not dependent on these
factors. Also, the similarities in processes used and waste
water characteristics in this production subcategory
substantiate the practicality of these technologies.
The processes used by the chemical plants in this subcate-
gory are very similar in nature and their raw wastes are
also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
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Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best available technologies is economically
achievable in the carbon monoxide and hydrogen by-product
production subcategory because most of the production sub-
category is currently using portions of the recommended
technology.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in other produc-
tion subcategories.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. The energy requirements for the
implementation of the recommended treatment technologies are
negligible.
CHROME PIGMENTS AND IRON BLUES Production Subcategory
Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is:
Effluent Characteristic
TSS
total chromium
chromium(6+)
lead
zinc*
oxidizable cyanide**
total cyanide**
iron**
Effluent Limitation -
kg/metrie ton jibs/ton)
0.33
0.017
0.0017
0.033
0.067
0.0017
0.017
0.067
(0.66)
(0.034)
(0.0034)
(0.066)
(0. 13)
(0.0034)
(0.034)
(0.13)
*Present only in complexes producing zinc yellow
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**Present only in complexes producing iron blues.
The above limitations were based on an average process
wastewater discharge of 33,400 liters per metric ton (8,000
gallons per ton) of product.
Identification of BATEA
Best available technology economically achievable for the
manufacture of chrome pigments and iron blues by the
standard process is removal of metal ions by multistage
chemical precipitation and separation; and if cyanides are
present, oxidation of cyanide by alkaline chlorination or
biological digestion.
To implement this technology at plants not already using the
recommended control techniques would require the installa-
tion of the necessary treatment tanks, clarifiers, filters,
etc., to accomplish the reduction of pollutants in the dis-
charged process waste water.
Reason for Selecti on
At present, none of the chrome pigment industry is using the
recommended technologies, but by mid-1974 this will increase
to about 33 percent when at least two facilities will have
completed installation of the equipment required to achieve
these levels.
Based up)on the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $3,000,000 to achieve limitations
prescribed herein. There are additional costs amounting to
approximately two percent of the average selling price of
these products.
None of this industry subcategory is presently achieving
this level of pollutant discharge, but by the end of 197U,
one-third of the industry production will be at the
recommended levels.
Age and Size of Equipment and Facilities
The data obtained on the chrome pigments and iron blues sub-
category represents plants with ages ranging from 25 to 58
years and production capabilities of similar magnitudes.
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The best available technology is economically achievable
regardless of the size or age of plants since the use of
existing technologies is not dependent on these factors.
Also, the similarities in processes used and waste water
characteristics in this production subcategory substantiate
the practicality of these technologies.
Processes Employed
The general processes employed in this production
subcategory are described in Section V of this report.
The processes used by the chemical plants in this
subcategory are very similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of these
recommended best available technologies is economically
achievable in the chrome pigments and iron blues production
subcategory because by the end of 1974 about one-third of
the production capacity of the industry will be utilizing
these technologies.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control
technologies are presently being implemented by plants in
this production subcategory.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category.
There appear to be no major energy requirements for the
implementation of the recommended treatment technologies.
COPPER SULFATE Production Subcategory
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Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable for the
production of copper sulfate from pure raw materials is:
Effluent Limitation -
kg/metric^ ton (Ibs/ton)
0.0002 (0.0004)
Copper
The above limitations are intended to control the carry-over
of pollutants into the barometric condenser water, even
though the available data does not indicate the presence of
copper salts.
For the production of copper sulfate from
process, the degree of effluent reduction is:
the recovery
TSS
Copper
Nickel
Selenium
Effluent Limitation -
kg/metric ton
0.0046
0.00046
0.00046
0.00023
(0.0092)
(0.00092)
(0.00092)
(0.00046)
The above limitations were based on an average process
wastewater discharge of 463 liters per metric ton (111
gallons per ton) of product.
_ BATEA
Best available technology economically achievable for the
manufacture of copper sulfate by the recovery process is
identical to best practicable control technology currently
available collection of waste liquor, process spills and
wash downs, treatment with lime, settling and filtration.
To implement this technology at plants not already using the
recommended control techniques would require the installa-
tion of collection facilities, a treatment tank, a settling
tank and filter presses.
Reason for Selection
A major copper sulfate (recovery process) plant presently
uses most of these technologies.
aljCgst^gf Application
320
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Based upon the information contained in Section VIII of this
report, the subcategory as a whole would not require an
appreciable additional investment to achieve the limitations
prescribed herein.
Age and Size of Equipment and Facilities
The data obtained on this subcategory represents a plant
that is approximately 50 years old.
The best available technology is economically achievable re-
gardless of the size or age of plants since the use of
existing technologies is not dependent on these factors.
Also, the similarities in processes used and waste water
characteristics in this production subcategory substantiate
the practicality of these technologies. The processes used
by the chemical plants in this subcategory are very similar
in nature and their raw wastes are also quite similar.
These similarities will enhance the application of the
recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best available technologies is economically
achievable in their production subcategory because a major
plant accounting for approximately 35 percent of the total
U.S. production of copper sulfate presently uses all of the
technology.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in other produc-
tion subcategories.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category.
FLUORINE Production Subeateqory
321
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Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is no
discharge of pollutants in process waste water from the
liquid hydrogen fluoride electrolysis process.
For the fused salt electrolysis process, no determination
has been made at this time because data is incomplete.
Identification of BATEA
Best available technology economically achievable for the
manufacture of fluorine by the fused-salt electrolysis
process is to treat all cell washdown with lime, filter and
evaporate. All scrubber water is recycled. To implement
this technology at plants not already using the recommended
control techniques would require collection facilities, a
treatment tank, filters, evaporation equipment and pumps and
associated equipment necessary for scrubber recycle.
No treatment technology is necessary for the liquid hydrogen
fluoride electrolysis process since the only plant that uses
this process has no process water discharge.
Reason for Selection
One plant studied has plans to install the recommended tech-
nologies except for evaporation.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $85 per metric ton to achieve
limitations prescribed herein. There is also an anticipated
increase in the operating cost equivalent to approximately
0.06 percent of the selling price of this product.
None of this industry subcategory is presently achieving
this level of pollutant discharge.
Age and Size of Equipment and Facilities
The data obtained on this subcategory represents plants up
to 3 years old.
The best available technology is economically achievable re-
gardless of the size or age of plants since the use of
existing technologies is not dependent on these factors.
322
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Also, the similarities in processes used and waste water
characteristics in this production subcategory substantiate
the practicality of these technologies. The processes used
by the chemical plants in this subcategory are very similar
in nature and their raw wastes are also quite similar.
These similarities will enhance the application of the
recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best available technologies is economically
achievable in the fluorine production subcategory because
these technologies are commonly used elsewhere in the
inorganic chemicals industry.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in other produc-
tion subcategories.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. There are energy requirements for imple-
mentating evaporation, but the quantities are unknown
because of AEC security.
HYDROGEN CYANIDE (ANDRUSSOW PROCESS)
Production Subcategory
Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is:
Effluent Characteristic
TSS
oxidizable cyanide
Effluent Limitation -
kg/metric ton (Ibs/ton)
0.045
0.00023
(0.090)
(0.00046)
323
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total cyanide 0.0023 (0.0046)
BOD5 0.096 (0.19)
ammonia (as N) 0.016 (0,032)
The above limitations were based on an average process
wastewater discharge of 4,500 liters per metric ton (1,080
gallons per ton) of product.
Identification of
Best available technology economically achievable for the
manufacture of hydrogen cyanide by the Andrussow process is
either: (1) send waste acid to other processes, oil separa-
tion, ammonia stripping, neutralization, biological
oxidation, f loeculation, clarification and filtration, or
(2) treatment with caustic and chlorine followed by
neutralization ard settling of suspended solids.
Reason for £e lection
The two plants stjdied, accounting for approximately one-
half of the total U,S, captive and merchant production of
this chemical, are presently using portions of one or the
other methods of treatment technologies recommended,
Total Cosjt of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $140,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately 2.0 percent
of the selling price of this product. It is concluded that
the benefits of the reduction of the discharge pollutants by
the selected control technology outweigh the costs. None of
this industry subcategory is presently achieving this level
of pollutant discharge.
The data obtained on the hydrogen cyanide (Andrussow
process) subcategory represents two plants with similar ages
and production capacities.
The best control technology available is economically
achievable regardless of the size or age of plants since the
use of existing technologies is not dependent on these
factors. Also, the similarities in processes used and waste
water characteristics in this production subcategory
substantiate the practicality of these technologies.
324
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Proc ess Employed
The processes used by the chemical plants in this
subcategory are very similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best control technologies economically achieva-
ble is practicable in this production subcategory because
the technologies exist and the important portions are in use
in two major plants.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in this produc-
tion subcategory.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These - solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy
requirements for the implementation of the recommended
treatment technologies .
MgHIUM_CARBQNATE_jSPODUMENS ORE) _Production_Subcateqory
Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is:
Effluent Limitation -
Effluent Characteristic kg /metric ton
Tss 0.36 (0.72)
325
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The above limitations were based on an average process
wastewater discharge of 36,000 liters per metric ton (8,600
gallons per ton) of product.
Identification of BAT$A
Best available technology economically achievable for the
manufacture of lithium carbonate from Spodumene ore is
neutralization, settling and polish filtration. To
implement this technology at plants not already using the
recommended control techniques would require the addition of
polish filtration.
Reason for Selection
The required technology is being used with the exception of
polish filtration which is necessary to reach this level of
suspended solids.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would have to invest up
to an estimated maximum of $20,000 to achieve limitations
prescribed herein. There is also an anticipated increase in
the operating cost equivalent to approximately less than 0.1
percent of the selling price of this product.
None of this industry subcategory is presently achieving
this level of pollutant discharge.
Age and Size of Equipment and Facilities
The data obtained on this subcategory represents one plant
19 years old.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best available technologies is economically
achievable in the lithium carbonate Spodumene ore extraction
production subcategory because it only requires the addition
of polish filtration.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. Most of these control
technologies are presently being used by the only plant in
this production subcategory.
326
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Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy
requirements for the implementation of the recommended
treatment technologies.
NICKEL SULFATE Production Subcateqory
Based upon the information contained in Sections III
through IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is no dis-
charge of pollutants in process waste water when the process
employs pure raw materials. When plating solutions are used
as raw materials in the process, the degree of effluent
reduction attainable is:
Effluent Limitation -
Effluent Characteristic kg/metric ton (Ibs/ton)
TSS 0.012 (0.024)
Nickel 0.002 (0.004)
The above limitations were based on an average process
wastewater discharge of 1,170 liters per metric ton (280
gallons per ton) of product.
Identification of BATEA
Best available technology economically achievable for the
manufacture of nickel sulfate using pure raw materials is
recycle of all process water. When the process employs
impure plating solution as the raw material, the BATEA is
treatment of process waste water with caustic to precipitate
nickel followed by sand filtration to remove suspended
solids. The basis for the nickel guideline is 1 mg/1 which
requires an improvement over the present treated effluent of
3 mg/1. However, it should be noted that a similar
treatment scheme is utilized in the copper sulfate
production industry to achieve a treated nickel
concentration of 0.5 mg/1.
327
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To implement this technology at plants not already using the
recommended control techniques would require the
installation of caustic treatment tanks, sand filters and pH
control.
Reason for Selection
The technology recommended is being used by at least one
plant accounting for over UO percent of this industry's
production.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would not require an
appreciable additional investment to achieve the limitations
prescribed herein.
Age and Size of Equipment and Facilities
The data represent plants with similar ages and production
capacities over a 20 to 1 range.
The best available technology is economically achievable
regardless of the size or age of plants since the use of
existing technologies is not dependent on these factors.
The similarities in processes used and waste water
characteristics in this production subcategory substantiate
the practicality of these technologies.
The processes used by the chemical plants in this
subcategory are very similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best available technologies is economically
achievable in the nickel sulfate production subcategory
because at least one plant accounting for over <40 percent of
the production uses most of the technologies specified.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in this
production subcategory.
328
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Non- Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category.
NITROGEN AND OXYGEN Production Subcateggry
The BATEA limitations are identical to those presented in
Section IX for BPCTCA.
POTASSIUM IODIDE Production SubcateaorY
Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is:
Effluent Limitation -
Effluent Characteristic kg/metric ton (Ibs/ton)
0.01U (0.028)
barium 0.0023 (0.0046)
ircm 0.0036 (0.0072)
sulfide 0.0036 (0.0072)
The above limitations are based on an average process
wastewater discharge of 900 liters per metric ton (215
gallons per ton) of product.
Identification of BATEA
Best available technology economically achievable for the
manufacture of potassium iodide by either process is
identical to best practicable control technology currently
available, i.e., collection of all process wastewater and
precipitation of heavy metals as the sulfide and barium or
the sulfate followed by settling and clarification. For the
process which generates iodate ion as a waste, treatment
with excess thiosulfate is recommended to reduce the iodate
ion to iodide.
Reason for Selection
329
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Neither plant employs any treatment technology for their
wastes. One plant does not have to because of its
geographical location. All waste water is evaporated. The
effluent limitations guidelines are for the other plant and
are based on solubility limits of the various precipitated
impurities in the waste water.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would not require an
appreciable additional investment to achieve the limitations
prescribed herein.
Age and Size of Equipment and Facilities
The data obtained on this subcategory represents plants with
ages ranging from 30 to 42 years.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best available technologies economically
achievable is practicable in the potassium iodide production
subcategory because one plant already has no discharge and
the treatment.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in other produc-
tion subcategories.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy
requirements for the implementation of the recommended
treatment technologies.
SILVER NITRATE Production Subcateqory
330
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Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is:
Effluent Limitation -
Effluent Characteristic kg/metric ton jibs/ton)
TSS 0.023 (0.046)
silver 0.0015 (0.0030)
The above limitations are based on an average process
wastewater discharge of 1,500 liters per metric ton (360
gallons per ton) of product).
Identification of BATEA
Best available technology economically achievable for the
manufacture of silver nitrate by the standard process is
identical to BPCTCA, i.e., to process all silver-containing
wastes through a silver recovery plant, followed by
trickling filters in series with activated sludge treatment,
neutralization and clarification.
Reasons for Selection
One plant accounting for over 60 percent of the total U.S.
production of silver nitrate is presently using this
treatment technology.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would not require an
appreciable additional investment to achieve the limitations
prescribed herein.
Age and Size of Equipment and Facilities
The data obtained on this subcategory represents plants with
similar ages.
The best available technology is economically achievable
regardless of the size or age of plants since the use of
existing technologies is not dependent on these factors.
Also, the similarities in processes used and waste water
characteristics in this production subcategory substantiate
the practicality of these technologies.
331
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The processes used by the chemical plants in this
subcateqory are very similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best available technologies is economically
achievable in the silver nitrate production subcategory
because most of the production subcategory presently uses
the technology.
Process Changes
The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in this produc-
tion subcategory.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect on land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the solid system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category. There appear to be no major energy
requirements for the implementation of the recommended
treatment technologies.
SODIUM SILICOFLUORIDE Production Subcateqory
Based upon the information contained in Sections III through
IX, a determination has been made that the degree of
effluent reduction attainable through the application of the
best available technology economically achievable is:
Effluent Limitation -
Effluent Characteristic kg/metric ton (Ibs/ton)
TSS 0.19 (0.38)
fluoride 0.25 (0.50)
The above limitations are based on an average process
wastewater discharge of 12,520 liters per metric ton (3,000
gallons per ton) of product.
332
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Identification of BATEA
Best available technology economically achievable for the
manufacture of sodium silicofluoride is identical to BPCTCA,
i.e., liming, settling or clarification.
Reason for Selection
The recommended technologies are the industry standard to
reduce fluoride and suspended solids in process waste water.
All of the production subcategory not using deep well
disposal employs these technologies.
Total Cost of Application
Based upon the information contained in Section VIII of this
report, the subcategory as a whole would not require an
appreciable additional investment to achieve the limitations
prescribed herein.
Age and Sige of Equipment and Facilities
The data obtained on this subcategory represents plants with
ages ranging from 16 to 36 years and production capacities
with a seven-fold range.
The best available technology is economically achievable re-
gardless of the size or age of plants since the use of
existing technologies is not dependent on these factors.
Also, the similarities in processes used and waste water
characteristics in this production subcategory substantiate
the practicality of these technologies.
Process Employed
The processes used by the chemical plants in this
subcategory are very similar in nature and their raw wastes
are also quite similar. These similarities will enhance the
application of the recommended treatment technologies.
Engineering Aspects
From an engineering standpoint, the implementation of the
recommended best available technologies is economically
achievable in the sodium silicofluoride production
subcategory because all the plants in the subcategory
discharging process water are already using the
technologies.
Process Changes
333
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The recommended control technologies would not require major
changes in the manufacturing process. These control tech-
nologies are presently being used by plants in other
portions of the inorganic chemical industry.
Non-Water Quality Environmental Impact
The single major impact on non-water quality factors of the
environment is the potential effect of land disposal of the
solids removed from the process waste waters. These solids
may sometimes contain harmful constituents which could be
detrimental to the soil system in the area of disposal or
possibly contaminate ground waters due to rainwater runoff
and percolation through the soil. Solid waste disposal from
inorganic chemical plants will be considered by the EPA as a
separate category.
334
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SECTION XI
NEW SOURCE PERFORMANCE STANDARDS
AND PRETREATMENT STANDARDS
This level of technology is to be achieved by new sources.
The term "new source" is defined in the Act to mean "any
source, the construction of which is commenced after the
publication of proposed regulations prescribing a standard
of performance". This technology is evaluated by adding to
the consideration underlying the identification of best
available technology economically achievable, a determina-
tion of what higher levels of pollution control are
available through the use of improved production processes
and/or treatment techniques. Thus, in addition to
considering the best in-plant and end-of-process control
technology, new source performance standards are how the
level of effluent may be reduced by changing the production
process itself. Alternative processes, operating methods or
other alternatives were considered. However, the end result
of the analysis identifies effluent standards which reflect
levels of control achievable through the use of improved
production processes (as well as control technology), rather
than prescribing a particular type of process or technology
which must be employed.
The following factors were considered with respect to
production processes which were analyzed in assessing the
best demonstrated control technology currently available for
new sources:
a) the type of process employed and process changes;
b) operating methods;
c) batch as opposed to continuous operations;
d) use of alternative raw materials and mixes of raw
materials;
e) use of dry rather than wet processes (including substitu-
tion of recoverable solvents for water); and
f) recovery of pollutants as by-products.
In addition to the effluent limitations covering discharges
directly into waterways, the constituents of the effluent
discharge from a plant within the industrial category which
would interfere with, pass through, or otherwise be
incompatible with a well designed and operated publicly
owned activated sludge or trickling filter waste water
treatment plant were identified. A determination was made
335
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of whether the introduction of such pollutants into the
treatment plant should be completely prohibited.
EFFLUENT_RE]DUCTION_ ATTAIN ABLE BY THE APPLICATION OF THE BEST
AVAILABLE DEMONSTRATED CONTROL TECHNOLOGIES. PROCESSES,
OPERATING METHODS OR"oTHER ALTERNATIVES^
Based upon the information contained in Sections III through
X of this report, the following determinations were made on
the degree of effluent reduction attainable with the
application of new source standards for the various
chemicals of the Significant Inorganic Products Segment of
the Inorganic Chemicals industry.
The process water, cooling water and blowdown guidelines for
new sources are identical to those based on best available
technology economically achievable. In addition, a process
water impoundment should be designed, constructed and
operated so as to contain the precipitation from the 25-
year, 24-hour rainfall event as established by the Office of
Hydrology of the National Weather Service, NOAA, for the
area in which such impoundment is located. it may discharge
that volume of process waste water which is equivalent to
the volume of precipitation that falls within the
impoundment in excess of that attributable to the 25-year,
24-hour rainfall event, when such event occurs.
The following industry subcategories were required to
achieve no discharge of process waste water pollutants to
navigable waters based on best available technology
economically achievable: ammonium chloride; borax;
bromine; calcium hydroxide; chromic acid; ferric chloride;
fluorine; hydrogen; hydrogen cyanide (acrylonitrile by-
product) ; iodine; lead monoxide; lithium carbonate (Trona
process) ; nickel sulfate (pure raw materials process) ;
potassium chloride; sodium fluoride; stannic oxide and zinc
sulfate. The same limitations guidelines are required as
new source performance standards.
The following industry subcategories are required to achieve
specific effluent limitations as given in the following
paragraphs.
Aluminum Fluoridg
Same as BATEA
Boric Acid
Same as BATEA
336
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Calcium Carbonate
Same as RATEA
Carbon Monoxide
Same as BAT FA
Chrome Pigments and Iron Blues
Same as BATEA
Copper Sul fate
Same an BATEA
Sri mo 4H HATEA
Same as BATEA
Nltrpgeo and Oxvggn
Same as BATEA
Iodide
as BATEA
,\s HA'I'KA
Sodi ^nj_si li cq^liaor Ide
Same as BATEA
Recommended pretreatment guidelines for discharge of plant
waste water into public treatment works conform in general
with EPA Pretreatment Standards for Municipal Sewer Works as
published in the July 19,1973 Federal Register and "Title UO
337
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- Protection of the Environment, Chapter 1 - Environmental
Protection Agency, Subchapter D - Water Programs - Part 128
- Pretreatment Standards" a subsequent EPA publication. The
following definitions conform to these publications:
a. Compatible Pollutant
The term "compatible pollutant" means biochemical oxygen
demand, suspended solids, pH and fecal coliform bacteria,
plus additional pollutants identified in the NPDES permit if
the publicly ovmed treatment works was designed to treat
such pollutants, and, in fact, does remove such pollutants
to a substantial degree. Examples of such additional
pollutants may include:
chemical oxygen demand
total organic carbon
phosphorus and phosphorus compounds
nitrogen and nitrogen compounds
fats, oils, and greases of animal or vegetable
origin except- as defined below in Pro-
hibi fed
b,_ln,eompat j blf\ Pollutant-
The term "incompatible pollutant" means any pollutant which
is not a compatible pollutant as defined above.
c. Joint Treatment Works
Publicly ovmed treatment works for both non-industrial and
industrial waste water.
d. Major Contributing industry
A major contributing industry is an industrial user of the
publicly owned treatment works that: has a flow of 50,000
gallons or more per average work day; has a flow greater
than five percent of the flow carried by the municipal
system receiving the waste; has in its waste, a toxic
pollutant in toxic amounts as defined in standards issued
under Section 307 (a) of the Act; or is found by the permit
issuance authority, in connection with the issuance of an
NPDES permit to the publicly owned treatment works receiving
the waste, to have significant impact, either singly or in
combination with other contributing industries, on that
treatment works or upon the quality of effluent from that
treatment works.
e. Pretreatment
338
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Treatment of waste waters from sources before introduction
into the joint treatment works.
Prohibited Wastes
No waste introduced into a publicly owned treatment works
shall interfere with the operation or performance of the
works. Specifically, the following wastes shall not be
introduced into the publicly owned treatment works:
a. Wastes which create a fire or explosion hazard in the
publicly owned treatment works;
b. Wastes which will cause corrosive structural damage to
treatment works, but in no case wastes with a pH lower
than 5.0, unless the works are designed to accommodate
such wastes;
c. Solid or viscous wastes in amounts which would cause ob-
struction to the flow in sewers, or other interference
with the proper operation of the publicly owned
treatment works, and
d. Wastes at a flow rate and/or pollutant discharge rate
which is excessive over relatively short time periods so
that there is a treatment process upset and subsequent
loss of treatment efficiency.
Pretreatment for Incompatible Pollutants
In addition to the above, the pretreatment standard for in-
compatible pollutants introduced into a publicly owned
treatment works by a major contributing industry shall be
best practicable control technology currently available;
provided that, if the publicly owned treatment works which
receives the pollutants is committed, in its NPDES permit,
to remove a specified percentage of any incompatible
pollutant, the pretreatment standard applicable to users of
such treatment works shall be correspondingly reduced for
that pollutant; and provided further that the definition of
best practicable control technology currently available for
industry categories may be segmented for application to
pretreatment if the Administrator determines that the
definition for direct discharge to navigable waters is not
appropriate for industrial users of joint treatment works.
Recommended Pretreatment Guidelines
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In accordance with the preceding Pretreatment Standards for
Municipal Sewer Works, the following are recommended for
Pretreatment Guidelines for the waste water effluents:
a. No pretreatment required for removal of compatible
pollutants - biochemical oxygen demand, suspended
solids, pH and fecal coliform bacteria;
b. Suspended solids containing pollutants such as heavy
metals, cyanides and chromates should conform to be
restricted to those quantities recommended in the
guidelines;
c. Pollutants such as chemical oxygen demand, total organic
carbon, phosphorus and phosphorus compounds, nitrogen
and nitrogen compounds and fats, oils and greases need
not be removed provided the publicly owned treatment
works was designed to treat such pollutants and will
accept them. Otherwise levels should be at or below
BPCTCA Guideline Recommendations;
d. Dissolved solids such as sodium chloride, sodium
sulfate, calcium chloride and calcium sulfate should be
permitted provided that the industrial plant is not a
"major contributing industry";
e. Plants covered under the "major contributing industry"
definition should not be permitted to discharge large
quantities of dissolved solids into a public sewer even
though they might be at the BPCTCA Guideline Recommenda-
tions of this report. Each of these cases would have to
be considered individually by the sewer authorities;
f. Discharge of all other incompatible hazardous or toxic
pollutantsj from the chemical plants of this study to
municipal sewers should> conform to BPCTCA guidelines
levels for discharge to surface water.
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SECTION XII
AC KNOWLEDGMENTS
This report was prepared by the Environmental Protection
Agency on the basis of a comprehensive study performed by
General Technologies Division of Versar Inc., under Contract
No. 68-01-1513. Dr. Robert G. Shaver, Project Manager,
assisted by Mr. E. F. Abrams, Mr. L. C. McCandless, Dr. C.
L. Parker, Mr. D. H. Sargent, and Mr. R. C. Smith, Jr. ,
prepared the origional (Contractor's) report.
This study was conducted under the supervision and guidance
of Mr. Elwood E. Martin, Project Officer for inorganic
chemicals, assisted by Mr. Elwood H. Forsht, Mr. James A.
Hemminqer, Mr. Joseph S. Vitaiis and Dr. Lamar Miller.
ll quidrtnee nnd excellent, aHaistance wan provided by
th«» author 'B anaociatoa la th«< Eftluent Guidelines Division,
particularly Messrs. Allen Cywin, Director, Ernst P. Hall,
Deputy Director, and Walter J. Hunt, Branch Chief.
The cooperation of manufacturers who offered their plants
for survey and contributed pertinent data is great fully
appreciated. The operations and the plants visited were the
property of the following companies:
Air Products and Chemicals Corporation
Airco Corporation
Aluminum Company of America
Allied Chemical Corporation
American Chemets Corporation
American Cyanamid Corporation
Aqua-Chem
Arkansas Chemical Company
At I an Powder Company
AVCO
BASF Wyandotte Corporation
Bird Machine Company
Bl aw- Know
Cabot Corporation
Calgon Corporation
Carus Chemical Company
Chemicals and Pigments Corporation
Chemical Products Corporation
Chemicals Separations Corporation
Chemtech Corporation
Cities Service Company
Conservation Chemical Company
341
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Copper Chemical Corporation
Cochrane Division, Crane Company
Deepwater Chemical Corporation
Diamond Shamrock Chemical Company
Dorr Oliver
Dow Chemical Company
E. I. duPont de Nemours and Company, Inc.
Duval Corporation
Eagle-picher Industries, Inc.
Eastman Kodak Company
Eimco
Envirogencis Company
Essex Chemical Corporation
Ferro corporation
FMC
Gardinier, Inc.
Goslin Birmingham, Inc.
Greenback Industries, Inc.
Gulf Environmental Systems Company
Harshaw Chemical Company
Hercules, Inc.
Hooker Chemical Corporation
International Minerals and Chemical Corporation
Kaiser Aluminum and Chemical Corporation
Kerr-McGee Corporation
Liquid Carbonic Corporation
Lithium Corporation of America
Mallinckrodt Chemical Works
Mineral Pigments Corporation
Mississippi Lime Corporation
M S T Chemicals, Inc.
National Lead Industries (N-L Industries)
New Jersey Zinc Company
Nichols Engineering Research Corporation
Occidental Petroleum
Office of saline1 Water, U.S. Department of the Interior
Olin Chemicals
Pennwalt Corporation
Ptizer, Inc.
Phelps Dodge Refining Corporation
Potash Institute of America
PPG Industries, Inc.
Resources Conservation Company
Rice Engineering and Operating, Inc.
Rohm and Haas Corporation
Sherwin Williams chemicals
Union carbide corporation
U.S. Atomic Energy Commission
U.S. Borax Corporation
U.S. Bureau of Mines, Reno Research Center
342
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U.S. Lime, Division Flintkote Company
Virginia Chemicals, Inc.
Vistron Corporation
Water Services Corporation
Wellman Powergas, Inc.
Wilson Engineering Company
Acknowledgment and appreciation is also given to Ms. Kaye
Starr, Ms. Nancy Zrubek, Ms. Alice Thompson, and Ms.
Ernestine Christian of the Effluent Guidelines Division
secretarial staff and to the secretarial staff of Versar
Inc., for their efforts in the typing of drafts, necessary
revisions, and the final preparation of this and the
contractor's draft document.
Thanks are also given to the members of the EPA working
group/steering committee for their advice and assistance.
They are:
Mr. Walter J. Hunt, Effluent Guidelines Division,
Chairman
Mr. Elwood E. Martin, Effluent Guidelines Division
Dr. Lamar Miller, National Field Investigation Center,
Cincinnati, Ohio
Dr. Murray Strier, Office of Permit Assistance
Ms. Judith Nelson, Office of Planning and Evaluation
Mr. Alan W. Eckert, Office of General Counsel
Mr. Joseph Davis, Region III
Mr. Richard B. Tabakin, Office of Research and
Development, NERC-Corvallis, Edison, New Jersey.
343
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SECTION XIII
REFERENCES
1. Faith, W.L., D.B. Keyes, and R.L. Clark, "Industrial
Chemicals", 3rd ed.r John Wiley and Sons, Inc., New York,
N.Y. (1965),
2. "Encyclopedia of Chemical Technology", 3rd ed., R. Kirk
and D.F. Othmer, eds. McGraw-Hill'Book Company, New York,
N.Y. (1965).
3. Shreve, R.N., "Chemical Process Industries", 3rd ed.
McGraw-Hill Book Company, New York, N.Y. (1967) .
4. "The Merck Index", 8th ed,, edited by P.G. Stecher, et al.
Merck and Co., Inc, Rahway, K.J. (1968).
5. Personal Communication, Pennwalt Corporation, 11/73.
6. Taylor, A.H,, "Industrial Gases: Industry's Workhorses",
Chem. Engr., 1973 Deskbook Issue, pp. 27-31 (October 8,
1973) .
7. "New Mexico Potash", Publication of New Mexico Potash
Industry^ Carlsbad, N.M. 88220, No date.
8. Personal Communication, Allied Chemical Corporation,
12/73.
9. "Current Industrial Reports - Inorganic Chemicals, 1971",
Bureau of the Census, U.S. Department of Commerce,
Series: M28&(72)-14 (October, 1972).
10. "Current Industrial Reports - Industrial Gases, 1972",
Bureau of the Census, U.S. Department of Commerce,
Series: M28C(72)-14 (July, 1973).
11. Sax, N. Irving, Dangerous Properties of Industrial Materials,
Van Nostrand Reinhold Co., New York, N.Y. 1968.
12. U.S. Public Health Service, Drinking Water Standards.
Revised 1962, U.S. Department of HealthT Education and
Welfare.
13. Report of the Committee on Watpr Quality Criteria^
Federal Water Pollution Control Administration, April 1968.
14. "Detection and Measurement of Stream Pollution," Contained
345
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in BiQ^oqy of Water Pollution. Federal Water Pollution
Control Administration, 1967.
15. Lund, Herbert F. , Industrial Poljj,u1^on Control Handbook.
McGraw Hill Book Co., New York, N.Y.
Metals in Caters o| the Un,ifr^fl s^ateg. Federal Water
Pollution Control Administration, 1967.
17. Handbook for Monitoring Industrial Wastewater, U.S.
Environmental Protection Agency, August 1973.
18. Environmental Protection Technology Series, Report No.
EPA-R2-73-269 (June 1973) - "Treatment of Complex Cyanide
Compounds for Reuse or Disposal", Office of Research and
Monitoring, U.S. Environmental Protection Agency,
Washington, D.C. 20460.
19. Unpublished Communications, "Cyanide Treatment with
Hydrogen Peroxide", Or. P. R. MucenieJcs, Research Labora-
tories, FMC Chemicals, Princeton, New Jersey.
20. Unpublished communications, "Sulfide Treatment with
Hydrogen Peroxide", Dr. P. R. Mucenieks, Research Labora-
tories, FMC Chemicals, Princeton, New Jersey.
21. Unpublished Communications, Chemical Research Laboratories,
E. I. DuPont Company - Cyanide Treatments.
22. Unpublished Communications, Calgon Corporation, Pitts-
burgh, Pa. - Cyanide Treatment.
23. Unpublished Communications, Allied Chemical Corporation,
Chemicals Division, Morris town,, New Jersey.
24. "Development Document for Proposed Effluent Limitations
(Juidt>lin«R «in
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26. Appendix to the Respondent's Brief (Organic Chemicals),
Nos. 74-1459, 74-1488, 74-1489, 74-1714, 74-1725, 74-1829,
74-1830, 74-1831, 74-1854, 74-1855, 74-1870 in the United
States Court of Appeals for the Fourth Circuit, Union Carbide
Corporation et. al.r Petitioners vs. Russell E. Train as
Administrator of the Environmental Protection Agency.
27. "Water Quality Criteria 1972", National Academy of
Sciences and National Academy of Engineering for the
Environmental Protection Agency, Washington, D.C. 1972
(U.S. Government Printing Office Stock No. 5501-00520).
347
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SECTION XIV
GLOSSARY
Acidity
The total titratable hydrogen ion content of the solution is
defined as th.e acidity. Acidity is expressed in ppm of free
hydrogen ion.
Adsorption
Condensation of the atoms, ions or molecules of a gas,
liquid or dissolved substance on the surface of a solid
called the adsorbent. The best known examples are gas/solid
and liquid/solid systems.
Air Pollution
The presence in the atmosphere of one or more air contami-
nants in quantities injurious to human, plant, animal life,
or property, or which unreasonably interferes with the com-
fortable enjoyment thereof.
Alkalinity
Total titratable hydroxyl ion concentration of a solution.
In water analysis, alkalinity is expressed in ppm (parts per
million) of calcium carbonate.
Ash
The solid residue left after incineration in the presence of
oxygen.
Bag Filter
A dry collection device for recovery of particulate matter
from gas streams.
Barometric Condenser
Device, operating at barometric pressure, used to change
vapor into liquid by cooling.
Barytes
A crude barium sulfate ore used as a starting material for
the production of barium chemicals.
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Biochemical Oxygen Demand, BODS
The BOD test is an empirical bioassay-type procedure which
measures the dissolved oxygen consumed by microbial life
while assimilating and oxidizing the organic matter present.
Standard test conditions include dark incubation at 20° for
a specified time period (usually 5 days).
Slowdown
A discharge from a system, designed to prevent a buildup of
some materials, as in a boiler to control dissolved solids.
An aqueous salt solution.
Calcination
The roasting or burning of any substance to bring about
physical or chemical changes; e.g., the conversion of
limestone to quicklime.
Carbonation
Treatment with carbon dioxide gas.
Catalytic Converter
A unit containing a packed or fluidized bed or catalyst.
Caustic
Capable of destroying or eating away by chemical action.
Applied to strong bases and characterized by the presence of
hydroxyl ions in solution.
Centrifuge
A device having a rotation container in which centrifugal
force separates substances of differing densities.
Chemical Oxygen Demand, COD
Its determination provides a measure of the quantity of
dichromate ion required to oxidize the organic matter (or
other oxidizable matter) in a waste sample, under specific
conditions of oxidizing agents, temperature and time. The
general method is applied to waste samples having an organic
carbon concentration greater than 15 mg/1.
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Coke
The carbonaceous residue of the destructive distillation
(carbonization) of coal or petroleum.
Conditioning
A physical and/or chemical treatment given to water used in
the plant or discharged.
Conductivity, Electrical
The ability of a material to conduct a quantity of electric-
ity transferred across a unit area, per unit potential
gradient per unit time. In practical terms, it is used for
approximating the salinity or total dissolved solids content
of water.
Cooling Water
Water which is used to absorb waste heat generated in the
process. Cooling water can be either contact or noncontacto
Copperas
Ferrous sulfate»
Cyclone Separator
A mechanical device which removes suspended solids from gas
streams.
Pennine ralization
The removal from water of mineral contaminants usually
present in ionized form. The methods used include ion-
exchange techniques? flash distillation or electrodialysis.
Digester
A pressure vessel or autoclave used to effect dissolution of
raw materials into aqueous solutions.
Effluent
The waste water discharged from a point source to navigable
waters.
Effluent Limitations
351
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A maximum amount per unit of each specific constituent of
the effluent that is subject to limitations in the discharge
from a point source.
Electrostatic Precipitator
A gas cleaning device using the principle of placing an
electrical charge on a solid particle which is then
attracted to an oppositely-charged collector plate.
Filtrate
Liquid after passing through a filter.
Filtration
Removal of solid particles from liquid or particles from air
or gas stream through a permeable membrane.
Floeculation
The combination or aggregation of suspended solid particles
in such a way that they form small clumps. The term is used
as a synonym for coagulation.
Flotation
A process used to separate ingredients in ores which is
based on density and surface chemistry differences among ore
constituents.
Fluidized Bed Reactor
A reactor in which finely divided solids are caused to
behave like fluids due to their suspension in a moving gas
or liquid stream.
Ganque
The worthless rock or other material in which valuable
minerals occur.
Gas Washer lor__wet_Scrubber]_
Apparatus used to remove entrained solids and other
substances from a gas stream.
Hardness (T
352
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The characteristic of water generally accepted to represent
the total concentration of calcium and magnesium ions,
usually expressed as ppm of calcium carbonate.
Heavy Metal
One of the metal elements not belonging to the alkali or
alkaline earth group. In this study, the classification
includes titanium, vanadium, iron, nickel, copper, mercury,
lead, cadmium, and chromium.
Ion Exchange
A reversible chemical reaction between a solid and a fluid
by means of which ions may be interchanged from one
substance to another. The customary procedure is to pass
the fluid through a bed of the solid, which is granular and
porous and has a limited capacity for exchange. The process
is essentially a batch type in which the ion exchanger, upon
nearing depletion, is regenerated by inexpensive salts or
acid.
Kiln (Rotary)
A large cylindrical mechanized type of furnace used for cal-
cination.
Membrane
A thin sheet of synthetic polymer, through the apertures of
which small molecules can pass, while larger ones are
retained.
Mother Liquor
The solution from which crystals are formed.
Multi-Effect Evaporator
In chemical processing installations, requiring a series of
evaporations and condensations, the individual units are set
up in series and the latent heat of vaporization from one
unit is used to supply energy for the next. Such units are
called "effects" in engineering parlance as, e.g., a triple-
effect evaporator.
Oleum or Fuming Sulfuric Acid
A solution of sulfur trioxide in sulfuric acid.
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2H
Is a measure of the hydrogen ion concentration of a
solution. A pH value of 7.0 indicates a neutral condition;
less than 7 indicates a predominance of acids, and greater
than 7, a predominance of alkalis. There is a ten-fold
increase (or decrease) from one pH unit level to the next;
e.g., ten-fold increase in alkalinity from pH 8 to pH 9.
Plant Effluent or Discharge after Treatment
The waste water discharged from the industrial plant. In
this definition, any waste treatment device (pond, trickling
filter, etc.) is considered part of the industrial plant.
Point Source
A single source of water discharge such as an individual
plant.
Pretreatment
The necessary processing given to materials before they can
be properly utilized or treated in a process or treatment
facility.
grocess Effluent or Discharge
The volume of waste water emerging from a particular use in
the plant.
Process Water
Water which is used in the internal plant streams from which
products are ultimately recovered, or water which contacts
the raw materials or product at any time.
Reverse Osmosis
A method involving application of pressure to the surface of
a saline solution forcing water from the solution to pass
from the solution through a membrane which is too dense to
permit passage of salt ions. Hollow nylon fibers or
cellulose acetate sheets are used as membranes since their
large surface areas offer more efficient separation.
Sedimentation
The falling or settling of solid particles in a liquid, as a
sediment.
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Settling Pond
A large shallow body of water into which industrial waste
waters are discharged. Suspended solids settle from the
waste waters due to the large retention time of water in the
pond.
Sintering
The agglomeration of powders at temperatures below their
melting points. Sintering increases strength and density of
the powders.
Slaking
The process of reacting lime with water to yield a hydrated
product.
Sludge
The settled mud from a thickener clarifier. Generally,
almost any flocculated, settled mass.
Slurry
A watery suspension of solid materials.
Solute
A dissolved substance.
Solvent
A liquid used to dissolve materials.
Thickener
A device or system wherein the solid contents of slurries or
suspensions are increased by evaporation of part of the
liquid phase, or by gravity settling and mechanical
separation of the phases.
Total Dissolved Solids (TDSL
The total amount of dissolved solid materials present in an
aqueous solution.
Total Organic Carbon
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A measurement of the total organic carbon content of surface
waters, domestic and industrial wastes, and saline waters.
Total Suspended Solids (TSS)
Solid parti culate matter found in waste water streams which,
in most cases, can be minimized by filtration or settling
ponds.
Turbidity
A measure of the opacity or transparency of a sediment -con-
taining waste stream. Usually expressed in Jackson units or
Formazin units which are essentially equivalent in the range
below 100 units.
Waste Discharged
The amount (usually expressed as weight) of some residual
substance which is suspended or dissolved in the plant
effluent.
Waste Generated (Raw Waste)
The amount (usually expressed as weight) of some residual
substance generated by a plant process or the plant as a
whole. This quantity is measured before treatment.
Water Consumption
The sum of all water consumed in the process: water of
product hydration, water of product solution, process waste
discharge, evaporation, cooling water discharge and cooling
tower windage and evaporation.
Water Recjrculation or Recycling
The volume of water already used for aom^ purpose in the
plant which is returned with or without treatment to be used
again in the tame or another process.
The total volume of water applied to various ueee in the
plant. It ii tht §um of water reoireuletion and water
withdrawal.
Wattr Withdrawal or Intake
3S6
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The volume of fresh water removed from a surface or
ground water source by plant facilities or obtained from
some source external to the plant.
Wet Scrubbing
A. gas cleaning system using water or some suitable liquid to
entrap particulate matter, fumes, and absorbable gases.
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