EP,
    Development Document for Effluent Limitations Guidelines
    and New Source Performance Standards for the
    SOAP  AND  DETERGENT
    Manufacturing
    Point Source Category
                     APRIL 1974
                U.S. ENVIRONMENTAL PROTECTION AGENCY
    ^\|^, <            Washington, D.C. 20460

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  ^.
I

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                    DEVELOPMENT DOCUMENT

                              for


                EFFLUENT LIMITATIONS

                              and

              NEW SOURCE PERFORMANCE STANDARDS



              SOAP AND DETERGENT MANUFACTURING
                   POINT SOURCE CATEGORY
                       Russell  E.  Train
                        Administrator
                          James L. Agee
  Acting Assistant Administrator for Water and Hazardous Materials

                          Allen Cywin
            Director,  Effluent Guidelines  Division

                        Richard T. Gregg
                        Project Officer
                           ApHI, 1974

                  Effluent Guidelines Division
               Office  of Water and Hazardous Materials
              U.S. Environmental Protection Agency
                     Washington, D.C.  20460
For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20102 • Price $2.35

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                            ABSTRACT
This document presents the findings of an extensive study of  the
soap and detergent manufacturing industry by Colin A. Houston and
Associates  for  the  Environmental  Protection  Agency  for  the
purpose of developing effluent  limitations  guidelines,  Federal
standards  of  performance,  and  pretreatment  standards for the
industry to implement Sections 304, 306 and 307  of  the  Federal
Water Pollution Control Act Amendments of 1972.

Effluent  limitations guidelines recommended herein set forth the
degree of effluent reduction attainable through  the  application
of  the  best  practicable control technology currently available
and  the  degree  of  effluent   reduction   attainable   through
application   of   the  best  available  technology  economically
achievable, which must be achieved by existing point  sources  by
July  1,  1977, and July 1, 1983, respectively.  The Standards of
Performance for new sources recommended herein set the degree  of
effluent reduction which is achievable through application of the
best   available   demonstrated  control  technology,  processes,
operating methods, or other alternatives.

The development of  data  and  recommendations  in  the  document
relate  to the nineteen subcategories into which the industry was
divided on the basis of raw waste loads and  appropriate  control
and  treatment  technology.   Separate  effluent  limitations are
proposed for each subcategory on the  basis  of  raw  waste  load
control  and  end-of-pipe treatment achievable by suggested model
systems.

Supportive data and rationales for development  of  the  proposed
effluent  limitations guidelines and standards of performance are
contained in this report.  Potential approaches for achieving the
limitations levels and their associated costs are discussed.
                                iii

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                       CONTENTS


Section                                                        Page

I              CONCLUSIONS                                        1

                 General                                          1
                 Categorization                                   2
                 History and Source of Data                       3
                 Integrated Plants                                3
                 Potential Developments                           4

II             RECOMMENDATIONS                                    5

III            INTRODUCTION                                      13

                 Purpose and Authority                           13
                 Limitations Guidelines and Standards            l1*
                  of Performance
                 General Description of the Industry             15
                   Historical                                    15
                   Companies and Markets                         16
                   Industrial Cleaning Compounds                 18
                   Sales and Production                          19
                   Physical Plant                                19
                   Trade Practices                               19
                   Industry Problems                             20
                   Future Trends                                 20
                 Soap Process Descriptions                       20
                   Soap Manufacture by Batch Kettle              20
                   Fatty Acid Manufacture by Fat Splitting       2^
                   Soap From Fatty Acid Neutralization           26
                   Glycerine Recovery                            29
                   Soap Flakes and Powders                       31
                   Bar Soap                                      33
                   Liquid Soap                                   35
                 Detergent Process Descriptions                  37
                   Oleum Sulfonation/Sulfation                   38
                   Air-S03 Sulfation/Sulfonation                 38
                   S03_ SoTvent and Vacuum Sul fonati on            Ui
                   Sulfamic Acid Sulfation                       id
                   Chlorosulfonic Acid Sulfation                 Hi
                   Neutralization of Sulfuric  Acid Esters        U5
                     and Sulfonic Acids
                   Spray Dried Detergents                        U5
                   Liquid Detergents                             U7
                   Dry Detergent Blending                        U9
                   Drum Dried Detergents                         1*9
                   Detergent Bars and Cakes                      53
                 Formulations                                    53

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Section                                                        Page

IV             INDUSTRY CATEGORIZATION                           59

                 Introduction                                    59
                 Categorization                                  60

V              WASTE CHARACTERIZATION                            63

                 Introduction                                    63
                 Soap Manufacture by Batch Kettle                63
                 Fatty Acids by Fat Splitting                    65
                 Soap by Fatty Acid Neutralization               66
                 Glycerine Recovery                              66
                 Soap Flakes and Powders                         68
                 Bar Soaps                                       68
                 Liquid Soaps                                    69
                 Oleum Sulfonation and Sulfation                 69
                 Air-SOS Sulfonation and Sulfation               70
                 S03 SoTvent and Vacuum Sulfonation              71
                 SuTfamic Acid Sulfation                         72
                 Chlorosulfonic Acid Sulfation                   72
                 Neutralization of Sulfuric Acid Esters          73
                  and Sulfonic Acids
                 Spray Dried Detergents                          7U
                 Liquid Detergent Manufacture                    75
                 Detergent Manufacturing by Dry Blending         77
                 Drum Dried Detergents                           7T
                 Detergent Bars and Cakes                        77

VI             POLLUTANT PARAMETERS                              79

                 Introduction                                    79
                 Control Parameter Recommendations               79
                   Biochemical Oxygen Demand                     79
                   Chemical Oxygen Demand                        81
                   Suspended Solids                              81
                   Surfactants (MBAS)                            82
                   Oil and Grease                                82
                   pH                                            83
                 Parameters Omitted                              84
                   Nitrogen                                      84
                   Phosphorus and Boron                          84
                 Scope of Parameter Measurements -               85
                  By Process
                   Soap Manufacture by Batch Kettle              85
                   Fatty Acids by Fat Splitting                  86
                   Soap by Fatty Acid Neutralization             86
                   Glycerine Recovery                            86
                   Soap Flakes and Powders                       87
                   Bar Soaps                                     87
                   Liquid Soap                                   87
                                 vi

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Section                                                         Page

                   Oleum Sulfonation and Sulfation                88
                   Air-SOS Sulfation and Sulfonation              88
                   S03_ Solvent and Vacuum Sulfonation             88
                   Sulfamic Acid Sulfation                        88
                   Neutralization of Sulfuric Acid Esters
                    and Sulfonic Acids                            89
                   Spray Dried Detergents                         89
                   Liquid Detergents                              90
                   Dry Detergent Blending                         90
                   Drum Dried Detergents                          90
                   Detergent Bars and Cakes                       90
                   Industrial Cleaners                            90

VII              CONTROL AND TREATMENT TECHNOLOGY                 93

                   Introduction                                   93
                   Nature of Pollutants                           94
                   Discussion of Treatment Techniques             95
                     Oil and Grease Removal                       95
                     Coagulation and Sedimentation                98
                     Bioconversion Systems                        ^
                     Carbon Absorption Systems                    9c
                     Filtration for Removal of Suspended          98
                      Solids
                     Dissolved Solids Removal                     99
                     Other Treatment Technique Considerations     99
                   Special Operational Aspects of Control         IOC
                     Technology
                   Solid Waste Generation Associated with         103
                     Treatment Technology

VIII             COST, ENERGY AND NONWATER QUALITY ASPECTS        105

                   In-Plant Control                               105
                     Impurities Removal                           106
                     By-product/Degradation Product Control       107
                     Dilute Product from Cleanouts, Leaks         108
                       and Spills
                   End-of-Pipe Treatment                          l"p
                   Energy Requirements                            113
                   Nonwater Quality Aspects                       113
                   Implementation of Treatment Plans              114

IX               BEST PRACTICABLE CONTROL TECHNOLOGY              117
                   CURRENTLY AVAILABLE

                   Introduction                                   117
                   Soap Manufacture by Batch Kettle               118
                   Fatty Acid Manufacture by Fat Splitting        123
                   Fatty Acid Hydrogenation                       126
                   Soap from Fatty Acid Neutralization            126
                   Glycerine Recovery                             127
                   Soap Flake and Powders                         130

                                   vii

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Section                                                         Page

                   Bar Soaps                                    131
                   Liquid                                       133
                   Oleum Sulfonation and Sulfation              134
                   Air-S03_ Sulfation and Sulfonation            135
                   503 Solvent and Vacuum Sulfonation           137
                   SuTfamic Acid Sulfation                      138
                   Chlorosulfonic Acid Sulfation                139
                   Neutralization of Sulfuric Acid Esters        140
                     and Sulfonic Acids
                   Spray Dried Detergents                       142
                   Liquid Detergent Manufacture                 146
                   Dry Detergent Blending                       148
                   Drum Dried Detergents                        149
                   Detergent Bars and Cakes                      150

X                BEST CONTROL TECHNOLOGY ECONOMICALLY           153
                   ACHIEVABLE

                   Introduction                                 153
                   Modified Soap Manufacture by Batch Kettle    155
                   Fatty Acid Manufacture by Fat Splitting      155
                   Glycerine Recovery and Concentration         159
                   Bar Soaps                                    162
                   Air-S03_ Sulfation and Sulfonation            166
                   S03 Solvent and Vacuum Sulfonation           166
                   SuTfamic Acid Sulfation                      166
                   Chlorosulfonic Acid Sulfation                166
                   Spray Dried Detergents                       166
                   Liquid Detergents                            167
                   Detergent Bars and Cakes                      167

XI               NEW SOURCE PERFORMANCE STANDARDS               169
                   AND PRETREATMENT STANDARDS

                   Introduction                                 169
                   Soap Manufacture by Batch Kettle             171
                   Soap from Fatty Acid Neutralization          172
                   Bar Soap - Drying                            173
                   Solvent Process for Soap  Manufacture         173
                   Oleum Sulfation and Sulfonation              174
                   Air-S03_ Sulfation and Sulfonation            174
                   Pretreatment Requirements                    183
                     Fats and Oils                              183
                     Fats and Oils - Detergent Plants           184
                     Zinc                                       184
                     Industrial Cleaners                        134

XII              ACKNOWLEDGEMENTS                               187

XIII             REFERENCES                                     189

XIV              GLOSSARY                                       195
                                   Vlll

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                                 TABLES
                                                                Page
           Summary Value of Shipments at Manufacturers            17
           Level Soaps and Detergents SIC 2841
2          Treatment Methods Used in Elimination of Pollutants    96
3          Relative Efficiency of Several Methods Used            97
           in Removing Pollutants
4          Range of Water Use by Process                         105
5          Cost and Energy Requirements Associated with          109
           Various Treatment Methods
6          Cost of Sludge Conditioning and Disposal Operations   115
7-1        Best Available Technology Economically Achievable     153
           Guidelines Reflecting No Change From Best Prac-
           ticable Control Technology Currently Available
7-2        Best Available Technology Economically Achievable     154
           Guidelines Reflecting Changes From Best Prac-
           ticable Control Technology Currently Available
8          New Source Performance Standards Guidelines           170
                                 ix

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                                FIGURES
Number                           Title                          Page
1          Soap Manufacture by Batch Kettle                       2?
2          Soap Making                                            25
3          Fatty Acid Manufacture by Fat Splitting                2?
4          Soap From Fatty Acid Neutralization                    28
5          Glycerine Recovery                                     30
6          Soap Flakes and Powders                                32
7          Bar Soaps                                              3^
8          Liquid Soap Processing                                 36
9          Oleum Sulfation and Sulfonation                        39
           (Batch and Continuous)
10         Air-S03^ Sulfation and Sulfonation                      ^0
           (Batch and Continuous)
11         S03_ Solvent and Vacuum Sulfonation                     !»2
12         Sulfamic Acid Sulfation                                ^3
13         Chlorosulfonic Acid Sulfation                          M
14         Neutralization of Sulfuric Acid Esters                 H6
           and Sulfonic Acids
                                 XI

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Number                           Title                          Page
15         Spray Dried Detergents                                48
16         Liquid Detergent Manufacture                          50
17         Detergent Manufacture by Dry Blending                 51
18         Drum Dried Detergent                                  52
19         Detergent Bars and Cakes                              54
20         Composite Flow Sheet Waste Treatment                 101
           Soap and Detergent Industry
21         Sludge Solids Handling Soap and Detergent Industry   102
22         Waste Water Sources in Soap Manufacture              120
23         Fat Splitting                                        121
24         Fats Recovery System                                 125
25         Glycerine Concentration                              128
26         Soap Manufacture by Batch Kettle: Modified           156
27         Modified: Fatty Acid Manufacture by Fat Splitting    157
28         Fatty Acids Manufacture: Hydrogenation Step,         158
           If Carried Out
                                 xli

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Number                           Title                          Page

29         Glycerine Recovery                                     160

30         Concentration of 80% Glycerine to 99.5%                161

31         Continuous Detergent Slurry Processing Plant           176
           High-Active Alkylate Sulfonation with Oleum

32         Continuous Detergent Slurry Processing Plant           177
           Fatty Alcohol Sulfation with Oleum

33         Soap Manufacture by Continuous Saponification          178

34         Soap by Continuous Fatty Acid Neutralization           179
           and Neat Soap Drying:  For Bar Soaps

35         Combined Processes SOS Sulfonation/Sulfation-          180
           Continuous and Neutralization of Sulfonic or
           Alky! Sulfuric Acid Processes-Continuous

36         Fatty Alcohol Sulfation: With S03_                      181

37         Alpha-Olefin Sulfonation with S03_                      182
                                 xiii

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                            SECTION I

                           CONCLUSIONS

General

The manufacturing of soaps and synthetic detergents represents  a
minor source of water pollution.  The industry uses approximately
15,160  million  liters  a  year  (or 4 billion gallons a year) as
process water.  The pollutants  emanating  from  its  plants  are
nontoxic and readily responsive to treatment.  Some exceptions to
this  statement  exist  in the industrial surfactant area and are
discussed  in  this  report.   More  than  95  percent  of  plant
effluents  go  to  municipal  treatment  plants  with less than 5
percent classed as point sources.

Virtually all of the 5.8 billion kilograms (12.8 billion  pounds)
of  product  estimated  from these plants in 1973 is destined for
the nation's treatment plants and waterways; the  intricacies  of
the  manufacturing  processes  of  this  industry  warrant better
understand ing.

Soaps and detergents are performance  products.   (By  dictionary
definition  a detergent is a cleaning agent and includes ordinary
bar soap, which is classically based on natural fat.  In  popular
usage,   however,   the   term  detergent  excludes  soap,  being
restricted to the family of cleaning  compounds  derived  largely
from   petrochemicals.    This  report  follows  popular  usage.)
Literally thousands of chemical compositions  can  be  formulated
which  clean  a  surface.    Detergents  can  be  formulated  with
entirely different organic and inorganic chemicals to exhibit the
same cleaning power or have the same biodegradability. They  also
can be formulated to:

1.  Maximize cleaning power

2.  Maximize biodegradability

3.  Minimize eutrophication potential in a specific recei-
    ving water

U.  Maximize cleaning power/unit cost

5.  Minimize air or water pollutants and solid wastes
    arising from the manufacturing processes.

Guidelines  can be directed toward minimized water pollution from
manufacturing, but not to the extent of  excluding  consideration
of  other  factors.   It  is possible today to design formulas to
give almost zero discharge of pollutants from  the  manufacturing
process.  However, the imposition of such low pollutant discharge
limits  on  water from the plants of the industry might result in
forcing radical reformulations  with  adverse  effects  in  other
areas  of  environmental  concern.   For example, one formulation

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which would enable a zero discharge from  a  manufacturing  plant
was voluntarily discarded by the industry 10 years ago because of
its poor biodegradability.


Categorization

For  the  purpose  of establishing effluent limitation guidelines
and standards of performance, the soap and detergent industry can
be divided into 19 subcategories based on processes and products.

                        SOAP MANUFACTURE

                           PROCESS DESCRIPTION

      Soap Manufacture - Batch Kettle and Continuous  (101)
      Fatty Acid Manufacture by Fat Splitting  (102)
      Soap From Fatty Acid Neutralization (103)
      Glycerine Recovery  (104)
      Glycerine concentration (101A)
      Glycerine Distillation  (104B)
      Soap Flakes & Powders  (105)
      Bar Soaps (106)
      Liquid Soap (107)

                      DETERGENT MANUFACTURE

                           PROCESS DESCRIPTION

      Oleum Sulfonation & Sulfation (Batch & Continuous)  (201)
      Air S03_ Sulfation and Sulfonation  (Batch & Continu-
      ous) (202)
      S03 Solvent and Vacuum Sulfonation  (203)
      Sulfamic Acid Sulfation (20U)
      Chlorosulfonic Acid Sulfation (205)
      Neutralization of Sulfuric Acid Esters & Sulfonic
      Acids (206)
      Spray Dried Detergents  (207)
      Liquid Detergent Manufacture (208)
      Detergent Manufacturing By Dry Blending  (209)
      Drum Dried Detergents  (210)
      Detergent Bars & Cakes  (211)
The code numbers shown after the processes are used  to  identify
them throughout this report.

These  subcategories  cover the major unit operations of the  soap
and synthetic detergent industry as  it  is  established  in   the
Federal  Standard Industrial Classification Manual, Industry  Code
Number  2841.   Some  special  processes  in  the  production  of
surfactants have been omitted, namely:

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   Amine Oxides     Quaternaries             Isethionates
   Amides           Alkyl Glyceryl Ether     Hydrotropes
   Taurides         Sulfonates

The  categories  covered in this report allow the permit granting
authority to identify the unit operations in a soap and detergent
plant and the  important  measurable  effluents  associated  with
each.   Where  several  units  are present in the same plant, the
permit granting authority can  establish  a  maximum  permissible
effluent  standard  for  a  given  plant  by  adding the effluent
allowable from each unit.  Where a  large  number  of  units  are
grouped  together  in a single plant it is possible to reduce the
total permissible effluent that would be  arrived  at  simply  by
adding  the  individual  units in that site.  Techniques for such
reduction are covered in the body of this report.


HIgTORY_AND SOURCE OF DATA

When the study was initiated on January 16, 1973, there  were  no
detailed   effluent   studies  available  on  this  industry.   A
literature search including previous EPA and state  work  yielded
little  useful  data.  The Corps of Engineers permit applications
yielded little correlatable data  since  information  as  to  the
products produced and any relationship of product or processes to
effluent  flows  was lacking.  Another problem then arose when it
was found that the soap and detergent companies possessed  little
or  no  detailed  data  regarding  their  effluent  flows.   Most
effluent data from the companies turned out  to  be  on  combined
sewers (combining the effluent of three to ten process units) and
hence  were  of  limited  value.   Therefore,  the sample program
orginally conceived by the EPA and Contractor  as  a  program  to
verify  literature  and  company-provided  information  had to be
enlarged and turned into a  major  research  project.   Though  a
relatively sound data base was obtained, ideally such data should
be  obtained  by  composite  sampling  over a period lasting from
thirty days to a year.  Because of the great pressure to complete
this work to enable the EPA to  publish  guidelines  October  18,
1973,  as  called  for  in  the  Act,  Public  Law 92-500, it was
impossible to run any composite program longer than one week.   A
number  of  the  sample  programs  initiated  are being continued
voluntarily by the companies, and more sophisticated  information
has begun to come in.

For publication of this report, it was necessary to foreclose use
of  further  data  June  15,  1973.  The data flow is expected to
continue and, after collation, is being turned over to the EPA as
received.  A major conclusion stemming  from  this  work  is  the
recognition  of  the  necessity  of arranging for a long term EPA
depository for industry effluent  data  so  that  water  handling
problems can be fairly and inventively dealt with.

Integrated Plants

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An important, conclusion reached in this study was that integrated
plants having a group of several unit processes at the same plant
site  have  a  substantial advantage in their ability to minimize
pollution by cascading water and working off the by-products from
one process into another unit process  step.   Although  we  have
indicated  many places where we believe the permit writer should,
for this reason, apply more lenient standards to the small one or
two unit process plant, this is really an area  needing  case  by
case evaluation.

Potential Developments

This  report  is written around soaps and synthetic detergents as
formulated in 1973.  From a national treatment standpoint, and to
lessen the possible eutrophication impact of soap  and  detergent
formulas,  it  may  be  necessary  to  change  the  1973 formulas
considerably.  Such changes will result  in  different  effluents
from  the  production  units.   In  the soap and glycerine field,
changes in formulation are not likely to be very pronounced,  but
they  are  in  detergent  bars, powders and liquids.  Substantial
changes in effluents from  unit  processes  and  hence  detergent
plants  may be necessary to minimize ecological impact of the end
product in specific receiving watersheds.  Particularly  in  this
industry,  the  guidelines  need  to  be reviewed periodically to
adjust to improvements in formulas.

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                           SECTION II

                         RECOMMENDATIONS

As a  result  of  the  findings  of  this  report  the  following
recommendations are made:

1.  That the effluent limitations and standards of performance be
based  on  the  level of waste reduction attainable as an average
for a thirty day period with the following values established for
the designated segments of the industry.   (All values  are  given
in  terms of kilograms (kg) of pollutant per kkg of the anhydrous
product produced in the numbered process given.   As  all  values
express weight to weight ratios the units are interchangeable and
Ib  can  be substituted for kg.  For example, 0.6 kg BOD5 per kkg
of product is an identical ratio to 0.6 Ib BOD5 per  1000  Ib  of
product.)


     Best Practicable Control Technology Currently Available

                            Suspended                  Oil &
   Subcategory   BOD5  COD    Solids     Surfactants   Grease

Soap Manufacture 0.60  1.50   0.40           NA         0.10
Batch Kettle

Fatty Acid       1.20  3.30   2.20           NA         C.30
Manufacture By
Fat Splitting

Hydrogenation    0.15  0.25   0.10           NA         0.10

Soap From Fatty  0.01  0.05   0.02           NA         0.01
Acid Neutrali-
zation

Glycerine Con-   1.50  4.50   0.20           NA         0.10
centration

Glycerine Dis-   0.50  1.50   0.20           NA         0.10
tillation

Soap Flakes      0.01  0.05   0.01           NA         0.01
and Powders

Bar Soaps        0.34  0.85   0.58           NA         0.04

Liquid Soaps     0.01  0.05   0.01           NA         0.01

Oleum Sulfona-   0.02  .09    0.03          0.03        C.07
tion & Sulfa-
tion (Batch 6
Continuous)

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Air-S03 Sulfa-   0.30  1.35   0.03          0.30        0.05
tion S Sulfona-
tion (Batch &
Continuous)

SO3 Solvent G    0.30  1.35   0.03          0.30        0.05
Vacuum Sulfona-
tion Sulfamic

Acid Sulfation   0.30  1.35   0.03          0.30        0.05

Chlorosulfonic   0.30  1.35   0.03          0.30        0.05
Acid Sulfation

Neutralization   0.01  0.05   0.03          0.02        0.01
of Sulfuric Acid
Ester 8 Sulfonic
Acids

Spray Dried      0.01  0.05   0.01          0.02        0.005
Detergents
(normal)


Spray Dried      0.08  0.35   0.10          0.15        0.03
Detergents
(air restrictions)

Spray Dried      0.02  0.09   0.02          0.03        0.005
Detergents
(fast turnaround)*

Liquid Deter-    0.20  0.60   0.005         0.13        0.005
gent Manufacture

Liquid Deter-    0.05  0.15   0.002         0.04        0.002
gent Manufacture
(fast turnaround) **

Detergent Manu-  0.01  0.07   0.01          0.01        0.005
facturing by
Dry Blending

Drum Dried       0.01  0.05   0.01          0.01        0.01
Detergents

Detergent        0.70  3.30   0.20          0.50        0.02
Bars & Cakes

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 *  Allowance for each turnaround in excess of six in a 30-day period.
**  Allowance for each turnaround in excess of eight in a 30-day period.

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        Best Available Technology Economically Achievable

                               Suspended                Oil &
    Subcategory    BOD5   COD   Solids    Surfactants   Grease

Soap Manufacture   0.40   1.05   0.40         NA         0.05
Batch Kettle

Fatty Acid Manu-   0.25   0.90   0.20         NA         0.15
facture by Fat
Splitting

Hydrogenation      0.15   0.25   0.10          NA        0.10

Soap From Fatty    0.01   0.05   0.02         NA         0.01
Acid Neutrali-
zation

Glycerine Con-     0.40   1.20   0.10         NA         0.04
centration

Glycerine  Dis-    0.30   0.90   0.04         NA         0.02
tillation

Soap Flakes        0.01   0.05   0.01         NA         0.01
and Powders

Bar Soaps          0.20   0.60   0.34         NA         0.03

Liquid Soap        0.01   0.05   0.01         NA         0.01

Oleum Sul-         0.02   0.09   0.03        0.03        0.07
fonation &
Sulfation
(Batch &
Continuous)

Air-SO3 Sul-       0.19   0.55   0.02        0.18        0.04
fation and
Sulfonation
(Batch & Con-
tinuous)

S03 Solvent        0.10   0.45   0.01        0.10        0.02
and Vacuum
Sulfonation

Sulfamic Acid    0.10  0.45   0.01          0.10        0.02
Sulfation

Chlorosulfonic     0.15   0.75   0.02        0.15        0.03
Acid Sulfation

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Neutralization     0.01   0.05   0.03        0.02        0.01
of Sulfuric Acid
Esters 6 Sulfonic
Acids

Spray Dried        0.01   0.04   0.02        0.02        0.005
Detergents (normal)

Spray Dried        0.06   0.25   0.07        0.10        0.02
Detergents (air
restrictions)

Spray Dried        0.02   0.07   0.02        0.02        0.005
Detergents (fast
turnaround)
Liquid Deter-      0.05   0.22   0.005       0.05        0.005
gent Manufacture

Liquid Deter-    0.02  0.07   0.002         0.02        0.002
gent Manufacture
(fast turnaround)

Detergent Manu-    0.01   0.07   0.01        0.01        0.005
facturing by
Dry Blending

Drum Dried         0.01   0.05   0.01        0.01        0.01
Detergents

Detergent Bars     0.30   1.35   0.10        0.20        0.02
6 Cakes

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             Standards of Performance for New Sources

                                Suspended               oil &
     Subcategory    BOD5   COD   Solids    Surfactants  Grease

Soap Manufacture    0.40   1.05   0.40         NA        0.05
Batch Kettle

Fatty Acid          0.25   0.90   0.20         NA        0.15
Manufacture by
Fat Splitting

Hydrogenation       0.15   0.25   0.10         NA        0.10

Soap From Fatty     0.01   0.05   0.02         NA        0.01
Acid Neutralization

Glycerine Con-      O.UO   1.20   0.10         NA        O.OU
centration

Glycerine Dis-      0.30   0.90   0.04         NA        0.02
tillation

Soap Flakes &       0.01   0.05   0.01         NA        0.01
Powders

Bar Soaps           0.20   0.60   0.34         NA        O.C3

Liquid Soap         0.01   0.05   0.01         NA        0.01

Oleum Sulfonation   0.01   0.03   0.02        0.01       0.04
& Sulfation (Batch
& Continuous)

Air-S03 Sulfa-      0.09   0.40   0.02        0.09       0.02
tion 6 Sulfona-
tion (Batch &
Continuous)

SO3 Solvent &       0.10   0.45   0.01        0.10       0.02
Vacuum Sulfonation

Sulfamic Acid       0.10   0.45   0.01        0.10       0.02
Sulfation

Chlorosulfonic      0.15   0.75   0.02        0.15       0.03
Acid Sulfation
                                   10

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Neutralization of   0.01   O.OU   0.03        0.02       0.01
Sulfuric Acid
Esters 6 Sulfonic
Acids

Spray Dried         0.01   0.04   0.02        0.02       0.005
Detergents (Normal)

Spray Dried         0.06   0.25   0.07        0.10       0.02
Detergents (Air
restricted)

Spray Dried         0.02   0.07   0.02        0.02       0.005
Detergents (Fast
turnaround)


Liquid Detergent    0.05   0.22   0.005       0.05       0.005
Manufacture

Liquid Detergent    0.02   0.07   0.0002      0.02       0.002
Manufacture (fast
turnaround)

Detergent Manu-     0.01   0.07   0.01        0.01       0.005
facturing by
Dry Blending

Drum Dried          0.01   0.05   0.01        0.01       0.01
Detergents

Detergent Bars      0.30   1.35   0.10        C.20       0.02
6 Cakes

The pH of final discharge(s)  should be within the range of
6.0-9.0 at all times.


2.   For  purposes  of  monitoring  and  enforcement, periods and
values other than those for the 30-day average should be adopted.
Daily maximums 3 times  and  2  times  the  30-day  averages  are
recommended  as  reflecting  reliability of control and treatment
for best practicable and best available control


3.  A continuing effort is recommended to further study the waste
water  effluent  problems  of  the  soap  and  detergent   field,
particularly  detergents.   The technology is in a state of rapid
flux and merits close observation.

Basically two areas should be considered:

     (a)   Changes in detergent formulations and how they affect
          wastes associated with manufacture and the environmental
                                   11

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     impact  resulting from use by the consumer.

(b)   Control and treatment practices as they affect
     water pollution,  air pollution, and solid waste.
                              12

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                           SECTION III

                          INTRODUCTION

Purpose and Authority

Section 301 (b) of the Act requires the achievement by  not  later
than  July  I/   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  eco-
nomically  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 304(b)  of 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 limitations setting forth the degree of
effluent reduction attainable through the application of the best
practicable control technology currently available and the degree
of effluent reduction attainable through the application  of  the
best  control  measures  and  practices  economically achievable,
including   treatment   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 soap and
detergent industry.

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.  1624),  a
list   of   27   source  categories.   Publication  of  the  list
constituted announcement  of  the  Administrator's  intention  of
establishing,    under   Section  306,   standards  of  performance
applicable to new sources within the soap and detergent category,
which was included within the list published January 16, 1973.
                                   13

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Limitations Guidelines and Standards of Performance

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 waste characteristics 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 constituents
(including thermal)  of all waste waters including toxic constitu-
ents and other constituents which  result  in  taste,  odor,  and
color  in  water or aquatic organisms.  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  technologies  existing
within   each  subcategory  was  identified.   This  included  an
identification of each distinct control and treatment technology,
including both inplant and end-of-process technologies, which are
existent or capable of being designed for each  subcategory.   It
also  included  an  identification  in  terms  of  the  amount of
constituents (including thermal) and the chemical, physical,  and
biological  characteristics  of pollutants, of the effluent level
resulting from the application  of  each  of  the  treatment  and
control  technologies.  The problems, limitations and reliability
of  each  treatment  and  control  technology  and  the  required
implementation  time  was 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 air, solid waste, noise and radiation were  also  iden-
tified.   The  energy  requirements  of  each  of the control and
treatment technologies was identified as well as the cost of  the
application of such technologies.

The  information,  as outlined above, was then evaluated in order
to determine what levels  of  technology  constituted  the  "best
practicable   control   technology  currently  available,"  "best
available  technology  economically  achievable"  and  the  "best
available  demonstrated  control technology, processes, operating
methods,   or   other   alternatives."    In   identifying   such
technologies,  various  factors  were considered.  These included
the total cost of application of technology in  relation  to  the
effluent reduction benefits to be achieved from such application,
the  age  of  equipment  and  facilities  involved,  the  process
employed, the engineering aspects of the application  of  various
types  of  control techniques, process changes, non-water quality
environmental impact  (including energy  requirements)  and  other
factors.

-------
The  data  for  identification  and  analyses were derived from a
number  of  sources.   These  sources   included   EPA   research
information,   published  literature,  a  voluntary  industrywide
audit, an extensive industry  plant  effluent  sampling  program,
qualified   technical   consultation,   and  on-site  visits  and
interviews at exemplary  soap  and  detergent  processing  plants
throughout  the United States.  All references used in developing
the  guidelines  for  effluent  limitations  and   standards   of
performance  for  new  sources  reported  herein  are included in
Section XIII of this document.

General Description of the Industry

This industrial category is  covered  under  Standard  Industrial
Code  2841  and  includes establishments primarily engaged in the
manufacture of  soap,  synthetic  organic  detergents,  inorganic
alkaline  detergents,  or  any  combination.   Crude  and refined
glycerine from vegetable  and  animal  fats  and  oils  are  also
included.    Excluded   from  this  category  are  establishments
primarily engaged in manufacturing shampoos or  shaving  products
and  synthetic  glycerine.  Also excluded are specialty cleaners,
polishing and sanitation preparations.

Historical

The industry which produces products  for  cleaning  of  fabrics,
dishes,  and  hard  surfaces  goes  back to the earliest recorded
history.  Clay tablets found in ancient Mesopotamia  dating  back
to  the  third  millenium  B.C., gave a soap recipe calling for a
mixture of potash and oil to be used  in  the  making  of  cloth.
Modern  soap  and  synthetic  detergent formulations and business
practices were shaped by a series of events which started in  the
1930s.   These  include  the  introduction  of  synthetic surface
active ingredients in the mid 1930s.   There  followed  the  war-
induced  shortage of the natural ingredients for soap making such
as tallow and coconut oils and the consequent rapid increase then
in the use of synthetics.

The discovery of  polyphosphate  builders  followed,  which  made
synthetic  laundry  products suitable replacements for soap.  The
scramble of soap and  detergent  companies  for  the  housewives'
favor  occurred  during the 1950s and determined market shares of
companies in the household segment even  today.   Finally,  there
began the formulation of detergent products to meet environmental
considerations.

The  first  environmental  reformulation consisted of a voluntary
industry  switchover  to  more   biodegradable   linear   benzene
sulfonate  surfactants  to  replace the original highly branched,
poorly degradable  benzene  sulfonates  in  the  1960s.   Shortly
thereafter the use of phosphate builders in detergents came under
attack  from  environmentalists.  Of the 3 nutrients, phosphorus,
nitrogen  and  carbon,  which  cause  eutrophication  of   lakes,
phosphorus  appears  to be the only nutrient amenable to control.
                                   15

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A series of events led to  today's  confusing  and  indeterminate
situation  vis-a-vis  phosphate  builders.  Nitrilotriacetic acid
use  was  begun  and  then  stopped   because   of   fears   over
teratogenicity.   Detergents  built with carbonates and silicates
were introduced and then somewhat squelched because some  of  the
products  represented  alkalinity  hazards  and  there  were also
problems  such  as  interference  with  flame   retardancy,   and
deposition of hard water reaction products on clothes.  Today the
search  for  a  safe,  effective  builder  to  replace  phosphate
continues  in  full  swing  with  citrates  and   multifunctional
compounds  such  as  carboxy methylene oxy succinate getting much
research effort.  Other detergent ingredients have also been  the
subject  of  concern as to their safety and environmental impact.
Enzymes are an example, and sales of enzyme-containing detergents
suffered for a time as a result.

Companies and Markets

The household detergent industry  is  dominated  by  three  large
companies.   The  largest  U.S. company has about one half of the
U.S.  sales and production.  The next two companies in size  each
have  about  one  sixth  of  the  U.S.  market.  The remaining 17
percent of the business is shared by over  300  companies.   Very
few companies beyond the five largest produce and market products
across   the   country.    The   smaller  companies  captured  an
appreciable portion of the market share of  the  big  three  with
non-phosphate  detergents  before  bad  publicity put a damper on
sales of phosphate-free laundry detergents.

Laundry detergents are the largest category of products  made  by
the  soap  and  detergent industry.  The number one selling brand
has held about a 25 percent share of the U.S. market for over two
decades.  This brand is the industry standard for  this  category
of  product  and  the  market  leader fights hard to maintain his
level  of  sales  of  household  detergents.    Other   detergent
companies  constantly  search  for  improved  products containing
better ingredients so they can get a bigger share of this market.
The cost  of  the  search  for  new  and  improved  products  has
increased  greatly  because  of the more sophisticated safety and
environmental approaches now needed.

In considering other household  cleaning  products,  it  will  be
noted that the big three producers have a less dominant position.
Liquid hand dishwashing detergents are next to laundry detergents
in  importance.   Although the largest companies do dominate this
market there are many private label products sold by  supermarket
chains  and  also  quite  a  number of brands marketed by smaller
companies.  The  liquid  hand  dishwashing  detergent  market  is
static  in  growth  because  of  the  constant  shift toward home
automatic dishwashers.

Automatic dishwashing detergents are produced in sizable  amounts
by  medium  and small sized firms as well as the larger detergent
companies.  This category of product has grown very rapidly  with
                                   16

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                                            TABLE 1

                       SUMMARY VALUE OF SHIPlENrS AT MANUFACTURERS LEVEL

                                SOAPS AND DETERGENTS SIC 2841

                        AFTER 1967 CENSUS OF MANUFACTURERS  (ADJUSTED)
                         1963                         1967                       1973
                      (in millions)                 (in millions)              (in  millions)

               Kilogratis   Pounds  Dollars  Kilogiaiis Pounds  Dollars Kilograms  Pounds   Dollars
All Soaps         605.1    1332.a   355.U     553711240.3   383.9540.41190.4   415.1

Glycerine
  Natural          63.6     140.0    26.0      65.8    145.0    36.0     68.1    150.0     35.0

Alkali
  Detergents      519.0    1143,2   200.2     670.1   1476.0   279.6    887.6   1955.0   384.5

Acid Type
  Cleaners        156.1     343.8    35.2     256.1    564.0    61.7    398.6    878.0   100.7

Synthetic
  Ore. Det.
  Household      2098.7    4622.7  1029.4    2513.5   5536.4  1235.4   3169.9   6982.2   1565.0

Synthetic Ore.
  Det. Non-
  Household       287.2     632.6   115.3     357.5    787.4   141.1    443.1    976.0   167.0

Soap and Other
  Det. NSK         38.6      85.0    17.6     166.2    366.0    73.2    332.3    732.0   146.4

Grand Total
  Soaps and
  Detergents     3768.3    8300.1  1778.7    4592.3  10115.1  2210.9   5840.1 12863.6   2813.7

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the  proliferation of the home automatic dishwasher.  With only a
third of the nation's  households  having  automatic  dishwashers
great growth can be expected to continue.

Household  specialty  cleaners  of  all  types  are  produced  by
hundreds of companies in  successful  competition  with  the  big
three.   This  is  possible  because the specialties require less
capital investment than spray dried  laundry  detergents.   Also,
specialties  are  amenable to smaller and localized marketing and
advertising programs.

As opposed to the production of detergents,  the  soap  producing
segment  of  the  industry  is  now  concerned primarily with the
production of toilet bars.  A modest amount of soap  is  used  in
synthetic  household  detergent  manufacture,  both in heavy duty
solid formulations and in  combination  detergent  -  soap  bars.
There is a possibility of a moderate increase in the marketing of
laundry  soap  if  more  local  ordinances prohibiting the use of
detergents were to be passed.  For a number of economic  reasons,
for  example,  the  doubling of the cost of natural fats and oils
used in soap manufacture within the last  year  alone,  it  seems
unlikely  that  soap sales will increase significantly from their
present levels.

The largest sales of bar  soaps  are  again  made  by  the  three
largest  companies.   In general, other soap companies specialize
in private label, specialty soaps, and institutional sales.

Glycerine is an important product of the industry.  It is made as
a  by-product  of  soap  production,   and   synthetically   from
petroleum-derived  propylene.  Glycerine is an important cosmetic
and food intermediate and many soap and detergent  companies  are
also  in these businesses.  Synthetic glycerine competes with the
naturally derived product.  Its synthesis bears  no  relationship
to  the fat-derived product, but in composition it is essentially
identical.

Glycerine is a mature chemical whose use is presently growing  at
the  rate  of  3  percent  a year.  The total 1972 estimated U.S.
production was  158  million  kilograms  (3U8  million  Ib)  with
exceptionally  high  exports  accounting for 29 million kilograms
(64 million Ib).  Synthetic glycerine (not included in SIC  2841)
is  estimated  to  have  accounted  for  approximately 91 million
kilograms (200 million Ib) of the total production in  1972  with
natural  glycerine production accounting for 68 million kilograms
(150 million Ib).  There are 3 new  fat  splitting  plants  under
construction  in  the  U.S.  which will give 3 new sources of by-
product glycerine.

Industrial Cleaning Compounds

Industrial cleaning compounds are also an important part of  this
industry.    Compounds  are  made  for  metal  cleaning,  textile
processing, food sanitation, and a host  of  other  applications.
                                    18

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Total  dollar value of the non-household cleaning market was $263
million in 1967 and is estimated at $373 million for 1973.  There
are a host of small companies and divisions of large companies in
this business area.  Most  producers,  though,  serve  a  limited
market and a limited geographical area.

Sales and Production

Table  I gives an estimate of dollar values and poundage produced
for the products comprising SIC 2841.  It is interesting that the
oldest product, soap, still securely retains an important market;
that is, toilet and bath bars.  Automatic dishwashing  detergents
are  growing  rapidly  and  these  products are even more vitally
affected  by  the  phosphate   controversy   than   are   laundry
detergents.

Physical Plant

In  general,  the  soap and detergent industry has not integrated
backwards toward their raw materials.  Basic raw  materials  come
from  a  host of supplier companies.  Caustic, fats, and oils for
soap making  come  from  chemical  and  agricultural  processors,
although  some  companies  do own coconut plantations.   Detergent
alkylate, alcohols and non-ionic surfactants  usually  come  from
large   chemical   and  petrochemical  companies.   Some  anionic
surfactant is also produced by suppliers, but in general the soap
and detergent companies  do, most  of  their  own  sulfation  and
sulfonation.   The  inorganic  builders  and other additives come
exclusively from supplier companies.

The three largest companies in the household market  have  plants
in  major  metropolitan  areas  across the country.  Not only are
distribution costs  important,  but  also  the  large  volume  of
products  makes  it  possible for one company to build economical
sized plants in a number of locations.  There are about 30  major
plants  for  production  of  heavy duty laundry detergents in the
United States.

Trade Practices

It is fairly common for the  major  companies  to  contract  with
other  companies  for toll processing.  In these arrangements the
soap and detergent company will buy  synthetic  detergent  bases,
send  them to a second company for reaction, and have the product
returned  for  further  compounding.   For   example,   detergent
alcohols  may  be bought by a soap and detergent company and then
toll ethoxylated by a petrochemical company and returned  to  the
soap and detergent company for further processing.

Another  business  arrangement  is  the  production  of  packaged
detergents by private label producers which are then sold by  the
major food chains under their own brand names.
                                    19

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The  capital  requirements for a spray dried detergent bead plant
limit the number  of  these  units.   To  be  competitive,  these
complexes  produce  volumes  on  the  order of 13,620 kg per hour
(30,000 Ib per hour) and cost up to  10  million  dollars.   Soap
making  equipment can be fairly capital intensive, especially the
newer  fat  splitting  and  fatty  acid  purification  processes.
Production  of  light-duty  liquid  detergents  and  dry  blended
products  require  less  capital  and  consequently   many   more
producers  are  found.   Freight is an important consideration in
shipping liquids.

Industry Problems

Foremost in difficulty is the phosphate problem.  Large  sums  of
money  have  been  spent both by detergent companies and by their
suppliers  to  find  phosphate   replacements.    To   date,   no
replacement has been found which is entirely safe, effective, and
economically  feasible.   Generally,  companies are reformulating
with lower phosphate levels, substituting  nonionic  for  anionic
organic  surfactants,  and  using  additional amounts of alkaline
builders like sodium carbonate and sodium silicates.

New product development is not as frequent and fruitful as in the
past.  It is much more difficult to produce  new  products  which
meet  environmental  requirements,  so development money leads to
fewer products.

An appreciable portion of the waste load encountered in soap  and
detergent  manufacturing  is  attributable  to  general practices
within the industry.  The industry is strongly oriented to  sales
promotion,  with sales promotion frequently pitched to emotion or
aesthetic factors which have  little  or  no  affect  on  product
performance.   This  has  led  to great variety in things such as
color, scent and opacity which  produce  the  need  for  frequent
cleanouts  to  avoid cross contamination and result in generation
of added waste loads.

Future Trends

The industry is growing at a rate of 5 percent per year.   It  is
secure  in the knowledge that its products are vitally necessary.
The relative standing of various industry  members  depends  upon
how  successfully they solve environmentally actuated formulation
problems.

SOAP_PROCESS DESCRIPTIONS

Each of the following process descriptions are associated with  a
process  flow  sheet.   All of the expected waste water effluents
are identified in the flow sheet by  name  and  code  number  for
quick reference.

SOAP MANUFACTURE BY BATCH KETTLE (101)
                                  20

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Most  of  the soap made by this process finds its way into toilet
bar form for household usage.   This  use  demands  freedom  from
offensive  odors,  and displeasing colors.  In order to meet this
requirement, the starting fats and oils must be  refined.   There
is  a  direct  relationship  between  quality of the fats and the
quality of the finished soap.

Fat Refining and Bleaching

There are several ways in which fats are  refined.   One  of  the
most  frequently  used  methods employs activated clay as the ex-
traction agent.  Activated clay, having a large ratio of  surface
area  to  weight,  is agitated with warm oil and filtered.  Color
bodies, dirt, etc., are removed,  usually  through  a  plate  and
frame  press.   The  clay is disposed of as solid waste.  A small
amount of clay remains in the refined fat.

The clay is often "activated" by being given  an  acid  treatment
itself by the clay supplier and is a source of sulfate ion build-
up in some soap recycling streams.

Other  ways in which fats are refined include caustic extraction,
steam stripping and proprietary aqueous chemicals.

When soap accounted  for  the  major  portion  of  the  soap  and
detergent  market, the Solexol process of extraction found use in
refining of fats and oils.  The design  of  this  liquid  propane
extraction process is based on the diminishing solubility of fats
in  liquid  propane  with  increasing  temperature.  The fats are
completely  miscible  at  48.84  C   (120  F)  but  become  almost
insoluble  at  82.14  C   (180  F)  and  most  of the color bodies
precipitate.

Color bodies fall to the  bottom  of  the  treating  tower  while
decolorized  oils  dissolved in liquid propane sit on the solvent
(liquid propane)  layer and are  recovered  from  the  top.   This
process  is  not  now  used  in  the United States, but should be
reexamined since it offers a way to eliminate water use and  thus
could again become economical as discharges must be reduced.

Soap Boiling

Although  a  very  old process, kettle boiling still makes a very
satisfactory product and in several well integrated manufacturing
plants this process has a  very  low  discharge  of  waste  water
effluents.

Making  a  batch of neat soap (65 - 70 percent soap in water)  can
take as long as four to six days to complete.  A series of  large
steel  tanks are used in a counter current manner to "boil" soap.
Their capacity can  be  as  high  as  54,480  kilograms  (120,000
pounds)   of  ingredients.  Ever weakening caustic streams are met
by enriched fat so that the caustic is essentially  exhausted  in
the  presence  of  fresh  fat.   In actual practice the fat never
                                   21

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                            101 SOAP MANUFACTURE BY BATCH KETTLE
         1011
RECEIVING
STORAGE-TRANSFER
1012 FAT REFINING
   AND BLEACHING
                                                                          1013  SOAP BOILING
— STEAM
/• STEAM
NaOH 	
STEAM-
SALT 	
SALT.
~1
FATTY ACIDS
LOW GRADE
SOAP SALES
«^-
-*•
— »•

SOAP
BOILING
KETTLE
^
1
1




NIGRE
PROCESSING
1
1
rn
NEAT SOAP TO
*" PROCESSING
AND SALE
GLYCERINE TO
*" RECOVERY
^ LOW GRADE SOAP
LOW GRADE
FATTY ACID
O
c
pa
                WASHOUTS
                  101102
\
WASTEWATER I
101231 |

I
\
SOLID WASTE
101209

1
t
BAROMETRIC
CONDENSATE
101218
                                                          SEWER LYES
                                                          101319
                                         BRINE AND ACID
                                         WASTEWATER
                                         101320

-------
leaves the tank in which it starts until  it  is  converted  into
neat  soap.   Just  the aqueous caustic stream flows from tank to
tank.

A simplified process description for kettle boiling soap follows:
Step 1
weigh in
fats 6 oils
and alkali

Step 5
drain off
spent lye
and send to
recovery

Step 9
add water
and heat to
close soap
for filling
change
Step 2             Step 3
turn on            add salt and
steam and saponify boil for
                   graining
Step 6
add water to
kettle and
boil closing
Step 10
settle and
draw off
neat soap
Step 7
add strong
alkali to
closed soap
Step 11
recycle
bottom nigre
to Step 1
Step 4
turn off
steam and
settle

Step 8
settle
and run
off lye
to Step 1
Neat Soap
Step 1 - Fats and oils are weighed in.  The caustic  stream  from
the  "extreme  change"  of  step 7 is run in as well as the nigre
from step 11.

Step 2 - Live steam is customarily released into the kettle where
it not only heats up the materials but also performs the stirring
function.  About three or four hours are consumed in this step.

StejD_3 - Graining is the act of separating the newly formed  soap
from  the  exhausted lye solution.  An operator adds salt or salt
solution  until  a  sample  withdrawn  with  a  trowel  separates
distinctly  into  soap  and  lye.  About  10 - 12 percent Nad is
required.

Step 4 - About four hours are needed  to  completely  settle  the
contents into two layers.
Step  5  -  The spent lye contains 7 -
sent to the glycerine recovery unit.
                        8 percent glycerine and is
Step 6 - "closed soap" is now made by adding fresh water  to  the
kettle  and  heating  it  to  make  a continuous creamy material,
dissolving the remaining glycerine and salt.

Step 7 - The "strong change" is  carried  out  by  adding  fresh,
concentrated  lye which saponifies the last remnants of fat.  The
batch is brought to a boil again, water is added until  the  soap
                                 23

-------
is closed, then the lye is run in.  Since the soap is not soluble
in the strong alkali it becomes grainy.

Step	8  -  Steam is shut off and the batch allowed to settle for
three hours.  The lye is run off and added to a  beginning  batch
in the "extreme kill."

Step  9  - Heating is again begun and water run in until the mass
is closed and boiling is continued until the soap  removed  on  a
trowel can be poured off in a transparent sheet.

Step  10 - Heat is turned off and the batch is allowed to settle.
Neat soap is drawn off the top and run off to be  processed  into
one of many forms of soap products.  The lower layer is the nigre
which  contains the color bodies, dark soap, etc.  It contains as
much as 20 - 25 percent of the kettle contents  (30 -  UO  percent
soap).   When the nigre becomes heavily loaded with impurities it
can itself be salted out, making a low grade soap for sale.

Step._ll - Frequently the nigre is recirculated to the kettle  for
the start of a new batch.

An overall schematic of the soap-making process is as follows:


The waste water from kettle boiling is essentially from the nigre
stream.   The nigre is the aqueous layer which contains the color
bodies generated in the soap making process, mostly  dark  soaps.
They  are  often  marketed  as industrial lubricants or low grade
special purpose soaps.  Where such a market can be established  a
kettle  boil  soap  process  is  already  at  the  zero discharge
effluent level except for the oil refining step.

Salt_Usage

In order to maintain suitable solubility for  proper  processing,
salt is added to the soap making process to maintain the required
electrolytic  balance.  Most of the salt charged into the process
is ultimately returned to it  from  the  glycerine  concentration
step,  which  will  be discussed later.  Practically every kettle
boiling soap  manufacturer  concentrates  his  glycerine  stream,
although only a few go on to the distillation of glycerine.

FATTY ACID MANUFACTURE BY FAT SPLITTING (102)

By  means  of  fat  splitting  very  low  grade fats and oils are
upgraded to high value products by splitting the glycerides  into
their  two  components, fatty acids and glycerine.  Fat splitting
is an hydrolytic reaction which proceeds as follows:

                 Fat + Water —> Fatty Acid + Glycerine

Using a Twitchell catalyst (an aromatic sulfonic acid) and a long
residence  time,  fats  can  be  split  at   nearly   atmospheric
                                 21*

-------
       f
Kettle Boil
                     Nigre
            Dark soap
            to market
Spent lye
Evaporator!
Concentrated
glycerine
                         Salt
                     SOAP MAKING
                                        FIGURE   2

-------
pressures.   Today,  however, most fat splitting takes place in a
high pressure, high temperature tower operated at around  34  atm
and 260°C  (500 psig and 500°F).

Heated  fat,  254°C  (490°F)  and under pressure, is fed into the
bottom of the tower and  water,  204°C  (400°F)  and  also  under
pressure,  is  fed  into  the  top.  The two streams mix counter-
currently and hydrolysis takes place, often in the presence of  a
zinc  or tin catalyst.   At the high temperatures employed the fat
is soluble to the extent in 12 - 25 percent of  water,  depending
upon which fat is used.

In  about  90  minutes the splitting can be as high as 99 percent
complete.  The glycerine by-product can be produced at a  variety
of concentrations depending upon how complete a fat hydrolysis is
desired.   More  concentrated  glycerine  can be provided at some
expense of fatty acid yields.

The crude acids are  flashed  in  a  pressure  reducer  and  then
distilled  at  0.0026  -  0.0039  atm  (2-3 mm)  pressure.  The
resulting product may be subjected to an additional process  step
of flash hydrogenation to reduce the amount of unsaturated acids.

SOAP FROM FATTY ACID NEUTRALIZATION  (103)

Soap  making by fatty acid neutralization exceeds the kettle boil
process in  speed  and  minimization  of  waste  water  effluent.
Although widely used by the large soap producers, it is- also very
popular with the smaller manufacturer.

This  route  from  the  acids  is  faster, simpler (no by-product
dilute glycerine stream to handle)  and "cleaner" than the  kettle
boil   process.   Distilled,  partially  hydrogenated  acids  are
usually used.

The fatty acid  neutralization  process  has  several  additional
advantages  over  the kettle boiling process.  It does not have a
large salt load to recycle, and has a free  alkali  concentration
in  the  order  of  0.1  -  0.2 percent, contrasted with around 1
percent in the kettle boiling process.

The reaction that takes place is substantially:

           Caustic + Fatty Acid 	 Soap

Often, sodium carbonate is used in  place  of  caustic  with  the
attendant  evolution  of  carbon  dioxide.  When liquid soaps  (at
room temperature) are desired, the more soluble  potassium  soaps
are  made  by  starting  with potassium hydroxide.  The potassium
soaps are used in the familiar liquid hand  soap  dispensers,  in
many industrial applications, and often as lubricants.

As  in  kettle  boiling soap manufacture, the most popular mix of
acids for bar soap  is  in  the  ratio  of  20:80  20/80  coconut
                                  26

-------
                                    102 FATTY ACID MANUFACTURE BY FAT SPLITTING
                1021 RECEIVING
                   STORAGE-TRANSFER
1022 FAT PRETREATMENT
                        1023  FAT SPLITTING
                                                     1024 FATTY ACID DISTILLATION
ro
FATS AND
OILS
CLAY 	
CATALYST-







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W22OI








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VESSELS

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SOLID WASTE
W22O9
i
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REFINED FATS
AND OILS
STEAM 	
CATALYST —
FATTY ACIDS
- AND SOAPS

WASHINGS
102221


PRESSURE
r REDUCTION j
, REACTOR 	 I |
<
PRESSURE I
1 — REDUCTION
1
hATTY
ACIDS
STE/
HYDROGEN
CATALYST-


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CAUSTIC SODA 	
SULFURIC ACID-
fCBUDE
GLYCERINE
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PROCESS CONDENSATE
1O2322

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1



-, BAROMETRIC
CONDENSER
FATTY ACIDS
"! 	 .__ * 1
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— i 	
i
*
' HYDHO-
GENATION
MULSION BREAKINC
AT SEPARATION
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SLOWDOWN
W24O4

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-STEAM
REFINED
FATTY ACIDS
FATTY ACID
h PITCH AND
RESIDUES

BAROMETRIC
CONDENSATE
102418

SPENT CATALYST
AND WATER WASHINGS
102423




-------
ro
oo
                           103 SOAP FROM FATTY ACID NEUTRALIZATION
             1031 RECEIVING

                STORAGE-TRANSFER
                                        1032 SAPONIFICATION
                                                                    1033 RECYCLE-REPROCESSING


CAUSTIC SODA — —
SODA ASH





















x




'
1
LEAKS, SPILLS, STORM
RUNOFFS, WASHOUTS.
103102

















MIXER



*

L>
WASTEWATER BRINES
103224

WASHOUTS I
103202

SOAP TO
•»• STORAGE •




REACTOR
1
1
1
1
i
1
1
1
1
1
1
1
U-
1
\
1
l_
•*-•
•*—


OFF QUALITY SOAP
TO LANDFILL 103325


WASHOUTS
103302
- SCRAP SOAP
— CAUSTIC SODA
1
1
1
*
SEWER LYES
103326

                                              FIGURE

-------
oil:tallow  oil  derived  acids.   A number of distilled tall oil
soaps  (tall oil is  derived  from  the  waste  streams  of  paper
manufacture) are also made for industrial purposes.

In  some  cases, the soap making process is operated continuously
in tandem with a fat splitting  process.   The  fatty  acids  and
caustic  solution  are proportionated into a reactor continuously
by pumps having a common variable speed drive.   The  appropriate
amount  of  salt  is  also  programmed in to maintain the correct
electrolyte content.

The resulting neat soap will have about 30 percent moisture.

To clarify the soap solution, the soap stream coming out  of  the
reactor  is sometimes filtered with clay.  The spent clay creates
a certain amount of solid waste and the filter  press  is  washed
out occasionally.  Otherwise this is a "clean" process.

The   neat   soap  is  further  processed  into  bars  or  liquid
formulations in the  same  manner  as  the  product  from  kettle
boiling.


GLYCERINE RECOVERY (104)

Concentrat ion

The  kettle  boiling  soap  process  generates  an aqueous stream
referred to as sweet water lyes.  This stream will contain 8-10
percent glycerine, a heavy  salt  concentration  and  some  fatty
materials.   It is processed by first adding a mineral acid (HCl)
to reduce the alkalinity.  This is followed by  the  addition  of
alum   which   precipitates   insoluble   aluminum   soaps.   The
precipitate carries other impurities down with it.  If the stream
were not treated with alum, there would be severe foaming in  the
evaporators,  and  the  contaminant would be carried forward into
the glycerine.  The cleaned up glycerine solution is sent to  the
evaporators.

The  evaporators  (in some smaller plants there will be only one)
are  heated  under  reduced  pressure.   The  partial  vacuum  is
generated  by a barometric condenser.  They frequently operate at
0.13 to 0.07 atm (660 mm - 710 mm or 26 - 28" Hg of vacuum).

As the glycerine is concentrated the salt comes out  of  solution
and is removed from the evaporation kettle, filtered and returned
to  the  soap  making  process.   In  many plants this separating
function is performed continuously with  a  centrifuge  with  the
filtrate being returned to the evaporator.

The glycerine is usually concentrated to 80 percent by weight and
then either run to a still to be made into finished glycerine, or
stored and sold to glycerine refiners.
                                  29

-------
  uo
  o
104 GLYCERINE RECOVERY
1041  RECEIVING
    STORAGE-TRANSFER
                      1042  LYE TREATMENT
                                              1043 GLYCERINE EVAPORATION
                                               1044 GLYCERINE STILL
                                       TREATED
                                      .GLYCERINE
                                       LIQUOR
                                       RECYCLE
                                                                        STEAM
                                                                                                                 STEAM
                                                                       CRUDE
                                                                       GLYCERINE
                                                                       SALT RECYCLE
                                                                       TO SOAP
                                                                       MANUFACTURE
1 1 1
* 1 *
GLYCERINE
FOOTS
104428
\
I
1
1
SOLID WASTE
104409





BAROMETRIC
CONDENSATE
104418
                                                    FIGURE
                                                                                           COOLING TOWER
                                                                                           SLOWDOWN
                                                                                           104404

-------
The  sweet  water  glycerine  from  fat  splitting  is flashed to
atmospheric pressure, thereby releasing a considerable amount  of
water  very  quickly.   This can provide a glycerine stream of 20
percent glycerine or more going to the evaporators.  Since  there
is  no salt used in fat splitting there will be none in the sweet
water.

The water from the barometric  condenser  used  in  concentrating
will be slightly rich in BOD5 due to the carryover of glycerine.

Distillation

The concentrated glycerine  (80 percent)is run into a still which,
under  reduced pressure, yields a finished product of 98+ percent
purity.  Here again a barometric condenser is used to create  the
partial vacuum.

At  room  temperature,  the  still bottoms (also called glycerine
foots) are a glassy dark brown amorphous  solid  rather  rich  in
salt.   Water  is  mixed  with the still bottoms and run into the
waste water stream.  This particular stream is very rich in BOD5,
and readily biodegradable.  Many alternative methods of disposal,
including incineration, have  been  evaluated,  but  the  general
practice is disposal in a waste water stream.

The  other  waste  water  stream, the barometric condenser water,
will  also  contribute  to  the  total  BOD5/COD  load  from  the
glycerine still.


Some glycerine refining is done by passing the dilute stream over
ion  exchange  resin  beds,  both  cationic and anionic, and then
evaporating it to 98+ percent  glycerine  content  as  a  bottoms
product.   This  method  is  suitable  where  there  are  copious
quantities of water available and energy costs are very high.

In the backwash of the ion exchange process the organic suspended
solids are stripped from the system.  The regeneration  cycle  of
both  types  of beds will add a significant dissolved solids load
to the waste water system.

There are frequently three sets, in series, of  both  cation  and
anion  exchange  resins  used  in  this  process.   Each  step is
designed to reduce the input load by 90 percent.  Seme of the fat
splitting plants are equipped with this type of unit.

SOAP FLAKES AND POWDERS (105)

Neat soap (65 - 70 percent hot soap solution) may or may  not  be
blended  with  other  products before flaking or powdering.  Neat
soap is sometimes filtered to remove gel particles and run into a
crutcher for mixing with builders.
                                  31

-------
                                        105 SOAP FLAKES AND POWDERS
         105!  RECEIVING
             STORAGE-TRANSFER
                            1052 FLAKING
                                CRUTCHING-DRYING
  1053 SPRAY DRYING
                              1054 PACKAGING
NEAT SOAPS


BUILDERS


ADDITIVES
-d
 -D
              FILTER BACKWASH
              105129
                              LEAKS, SPILLS. STORM
                              RUNOFFS, WASHOUTS.
                              105202
WASTEWATER
1053O1

GASES
LEAKS, SPILLS, STORM
RUNOFFS, WASHOUTS.
1053O2
                                                                                                    SCRUBBER
                                                                                                    WASTEWATER
                                                                                                    1054O1
                                                                                                                  PACKAGED
                                                                                                                  SOAP TO
                                                                                                                  WAREHOUSE
                                                    FIGURE

-------
After thorough mixing, the finished formulation  is  run  into  a
flaker.   This unit normally consists of a two roll "mill" having
two steel rolls.  The small upper one is steam-heated  while  the
larger  lower  one  is chilled.  The soap solidifies on the lower
one and is slit into ribbons as it sheets off the roller.

The ribbons are fed into a continuous oven  heated  by  hot  air.
The  emerging  flakes  contain 1 percent moisture.  As all of the
evaporated moisture goes to the atmosphere,  there  is  no  waste
water effluent.

In spray drying, crutched, heated soap solution is sprayed into a
spray  tower,  or  flash-dried by heating the soap solution under
pressure and releasing the steam in the spray dryer under reduced
pressure.  In either case the final  soap  particle  has  a  high
ratio  of  surface area to unit of weight, which makes it readily
dissolvable in water.

Some operations will include  a  scrap  soap  reboil  to  recover
reclaimed  soap.  The soap reboil is salted out for soap recovery
and the salt water is recycled.   After  frequent  recycling  the
salt  water becomes so contaminated that it must be discharged to
the sewer.

Occasional washdown of the crutcher may be needed.  The tower  is
usually  cleaned  down' dry.  There is also some gland water which
flows over the pump shaft picking up any minor leaks.  This  will
contribute a very small, but finite, effluent loading.

BAR SOAP  (106)

The  procedure  for  bar soap manufacture will vary significantly
from plant to plant,  depending  upon  the  particular  clientele
served.  The following description typifies bar soap manufacture.

In  some  processes  additives  are mixed with the neat soap in a
crutcher before any drying takes place.  Another approach  is  to
begin  the  drying  process  with  the  hot neat soap going to an
"atmospheric" flash dryer followed by a vacuum  drying  operation
in  which the vacuum is drawn by a barometric condenser.  Soap is
then double extruded into short ribbons  or  curls  and  sent  to
plodders  for  further  blending or physical processing.  At this
point the soap  will  normally  have  8  -  14  percent  moisture
depending upon the previous course of processing.

Next,  a  milling  operation  affords the opportunity to blend in
additives as well as modify the physical properties of the  soap.
This  operation  has  much  more significance than just achieving
uniformity in the  mixing  of  further  added  ingredients.   The
physical  chemistry  of  soap is fairly complex.  Unless a bar of
soap is almost predominately left in the Beta phase, as  distinct
from  the  Omega phase, longrange solubility, warping resistance,
and lathering properties are poor.  Rapid chilling  of  the  soap
                                  33

-------
     U)
     jr-
                                             106 BAR SOAPS
       1061  RECEIVING
            STORAGE-TRANSFER
                          1062 CRUTCHING AND DRYING
                                                                     1063 SOAP MILLING
                                                                               1064  PACKAGING
NEAT SOAP
-HD-
ADDITIVES-»-i   \
FILTER
STRAINER
            FILTER BACKWASH
            1 06129
                                WATER
                       TO SOAP
                       MILLING
                                                                         WATER
                                                                                                                      SCRAP TO
                                                                                                                    -•-SOAP
                                                                                                                      RECYCLE
                                                                                                                 FINISHED SOAP
                                                                                                             —|-»-8ARS AND CAKES
                                                                                                                 TO WAREHOUSE
                                                        FIGURE   7

-------
 puts it predominantly  in Omega phase but successive milling  steps
 bring it back into Beta phase - hence the importance of milling.

 The  mill  consists  of  two polished rolls rotating at different
 speeds to maximize the shearing forces.  After milling, the  soap
 is cut into ribbons and sent to the plodder.

 The  plodder  operates much  like  a  sausage  grinder.  It thus
 extrudes and cuts the  soap into small chips, followed by  further
 mixing  in which all of the individual pieces are melted together
 into an homogeneous mass.  The plodder is  often  operated  under
 reduced  air  pressure so that any occluded air is removed in the
 blending process.  It  has a powerful screw that forces  the  soap
 through minute holes in a perforated plate.

 Plodding  completed,   the  soap  is  extruded  continuously  in a
 cylindrical form, cut  to size, molded into the desired form,  and
 wrapped  for  shipment.   Most  of the scrap in this operation is
 returned to the plodder.

 At times there will be soap scrap which has  become  too  dry  to
 process  properly  in  the  plodder  and  it  must be returned to
 earlier steps in the soap making process.

 The amount of water used in bar soap manufacture varies  greatly.
 In  many  cases  the entire bar soap processing operation is done
 without generating a single waste water stream.  The equipment is
 all cleaned dry, without any washups.  In  other  cases,  due  to
 housekeeping requirements associated with the particular bar soap
 process,  there  are   one  or  more  waste water streams from air
 scrubbers.

 Since we are dealing with a consumer product with  very  distinct
 (and important to the  consumer)  esthetic properties, all of these
 processes  can  claim  significance and essential character in the
 making of a particular bar.

 Occupying a very minor position in the soap market,  a  bar  made
 from  cold  frame  soap  may  be found.  After the saponification
 reaction, this soap is poured  directly  from  the  reactor  into
 molds.   Upon  cooling  and the completion of saponification, the
 molded soap is cut into bars.  The en-tire  operation  is  carried
 out without the generation of any waste water.

 LIQUID SOAP XI071

 Neat soap (often the potassium soap of fatty acids)  is blended in
 a  mixing tank with other ingredients such as alcohols or glycols
to produce a finished product, or with pine oil and kerosene  for
 a  product  with  greater  solvency  and  versatility.   The final
blended product may be, and  often  is,  filtered  to  achieve  a
sparkling clarity before being drummed.
                                 35

-------
                                        107 LIQUID SOAP PROCESSING
                 7077  RECEIVING
                     STORAGE-TRANSFER
                                                 1072 BLENDING
                                                                                 7073  PACKAGING
POTASSIUM SOAPS
ADDITIVES
SOLVENTS
                                                      WASH DOWNS;
                                                      HEELS. 707272
LEAKS, SPILLS, STORM
RUNOFFS, WASHOUTS.
707702
                                                                                      PACKAGING
                                                                                      EQUIPMENT
                                                                                    LI QUID SOAPS
                                                                                   •TO WAREHOUSE
WASHOUTS
107302
                                                     FIGURE    8

-------
In making liquid soap, water is used to wash out the filter press
and other equipment.  Waste water effluent is minimal.
DETERGENT PROCESS DESCRIPTIONS

The  first  modern  detergent  introduced in the United States in
1933 was an alkyl naphthalene sulfonate.  The primary reason  for
the  success  of detergents is their ability to overcome the hard
water behavior of soaps.  Even though the detergents  also  react
with  hard water minerals, the resulting compounds are themselves
soluble, or remain colloidally dispersed  in  the  water  system.
There are four main groups of detergents:

Anionics
Cationics
Amphoterics
Nonionics
Anionics  comprise  the most important group of detergents.  They
are usually the sodium salts of an organic sulfate or  sulfonate.
Sulfates  are made from long chain "fatty alcohols"  (of animal or
petroleum origin) .  Sulfonates generally are made from alkyl aryl
precursors.

By 1957 synthetic detergents took over 70 percent of  the  market
for soap- like products in the United States.
Cationic  detergents  are  known  as "inverted soaps" because
long chain ion is of the opposite charge to that of a  tr^c  soap
when dispersed in water.

This  class  of  detergents is made in quite small volumes.  They
are relatively expensive and somewhat harsh on  the  skin.   They
make  excellent  bacteriostats  and fabric softeners and are used
for this purpose.

Nonionic detergents are an increasingly popular active ingredient
of automatic washing machine formulations.   These  products  are
unaffected by hard water (they do not form ions) and are very low
foamers  (minimum  foam  when  agitated) .   They  are made by the
addition of ethylene oxide to an alcohol.

Amphoterics are those surface active agents which can  either  be
anionic  or cationic, depending upon the pH of the system wherein
they work.   An important class chemically, they account for  only
a very small portion of the detergent market.

DETERGENT MANUFACTURING PROCESSES
                                 37

-------
A  finished,  packaged detergent customarily consists of two main
components, the active ingredient (surfactant)  and  the  builder.
The function of the surfactant is essentially that of wetting the
substrate  to  be  cleaned.   The builder performs many functions
including buffering the  pH,  soil  dispersion,  and  soil  anti-
redeposition.   Both classes of materials are required for proper
detergent performance.

The  processes  described  under   this   heading   include   the
manufacture  of  the  surfactant  as  well  as preparation of the
finished detergent.  The  number  following  the  title  of  each
process refers to the process flow chart.

OLEUM SULFONATION/SULFATION (201)

One of the most important active ingredients of detergents is the
alcohol  sulfate  or  alkyl  benzene sulfonate - and particularly
those products made via the oleum route.

In  most  cases  the   sulfonation/sulfation   is   carried   out
continuously  in  a reactor where the oleum (a solution of sulfur
trioxide in sulfuric acid)  is brought into intimate contact  with
the  hydrocarbon  or  alcohol.  Reaction is rapid.  The stream is
then mixed with water and sent to a settler.

Prior to the addition of  water  the  stream  is  an  homogeneous
liquid.   With  the  addition  of  water,  two phases develop and
separate.  The dilute sulfuric acid  is  drawn  off  and  usually
returned  to  an  oleum  manufacturer  for reprocessing up to the
original strength.  The sulfonated/sulfated material is  sent  on
to be neutralized with caustic.

This  process  is  normally  operated  continuously  and performs
indefinitely without need of periodic  clean  out.   Pump  glands
occasionally  leak.  Anticipating this problem, a stream of water
is normally played over pump shafts to pick up such a leak is  it
occurs,  as  well  as  to cool the pump.  The flow of waste water
from this source is quite modest but continual.

AIR-S03 SULFATION/SULFONATION  (202)

This process  for  surfactant  manufacture  has  numerous  unique
advantages  and  is  used extensively.  In the oleum sulfation of
alcohols,  formation  of  water  stops  the  reaction  short   of
completion  because  it reaches a state of equilibrium, resulting
in low yields.

With SO3 sulfation, no  water  is  generated,  hydrolysis  cannot
occur and the reaction proceeds in one direction only.

The  absence  of  water  in  the  SO3  reaction  is  of  a lesser
importance in sulfonation.   What is particularly  troublesome  in
the  use  of  oleum for alcohol sulfation is that water cannot be
used for oleum separation due to the  potential  hydrolysis  that
                                 38

-------
201 OLEUM SULFATION AND SULFONATION (BATCH AND CONTINUOUS)
2011  RECEIVING
    STORAGE-TRANSFER
2012 SULFONATION

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    SEPARATION

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                                                                            SULFONIC ACID
                                                                            ANDSULFURIC
                                                                            ACID ESTER TO
                                                                            NEUTRALIZATION
                              FIGURE

-------
              202  AIR-SO, SULFATION AND SULFONATION (BATCH AND CONTINUOUS)
              2027  RECEIVING
                  STORAGE-TRANSFER
2022 SULFUR BURNING
                                                                           2023 SULFONATION-SULFATION
SULFURf
SO3 LIQUID
ALKYL BENZENE
ALCOHOLS
ETHOXYLATES
                                                                                                SULFONIC ACID AND
                                                                                              ^SULFURIC ACID ESTER
                                                                                                TO NEUTRALIZATION
                                                                                                AND SALES
                 LEAKS, SPILLS, STORM
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                 202/02
SULFURIC ACID
202309




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202302
                                               FIGURE   10

-------
would  take  place.   Even  if  this  were  not a worry, no phase
separation of the components takes place  with  the  addition  of
water to sulfated alcohols in oleum.

SO3.   sulfonation/sulfation  is  also  quite  amenable  to  batch
processing and in this  manner  can  produce  products  having  a
minimum  of sodium sulfate (all of the excess of SO^r or sulfuric
acid in the case of oleum sulfonation,  will  be  converted  into
sodium sulfate in the neutralization step with caustic) .  Another
advantage  of  the  SO3_  process  is  its ability to successively
sulfate and sulfonate an alcohol and a hydro-carbon respectively.

Care must be excercised in the SO3 process  to  control  reaction
conditions   -   particularly  temperature  -  to  minimize  char
formation and possible sulfonation of the  hydrocarbon  chain  of
the alcohol.

Because  of  this  reaction's  particular  tendency  to  char the
product, the reactor system  must  be  cleaned  thoroughly  on  a
regular  basis.   In  addition there are usually several airborne
sulfonic acid streams which must  be  scrubbed,  with  the  waste
water going to the sewer during sulfation.
     can  be  generated  at the plant by burning sulfur or sulfur
dioxide with air instead of obtaining it as a  liquid.   See  the
accompanying  flow  sheet for the process.  For further technical
information see Section X.

SO3 SOLVENT AND VACUUM SULFONATION  ( 203)

Undiluted SO3_ and  organic  reactant  are  fed  into  the  vacuum
reactor  through  a  mixing nozzle  (vacuum maintained at 0.06 atm
(5" Hg) .  Recycle is accomplished by running the flashed  product
through  a  heat  exchanger  back  into  the  reactor.   The main
advantage  of  the  system  is  that   under   vacuum   the   S
-------
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                     203 - SO3  SOLVENT AND VACUUM SULFONATION
              2031 RECEIVING
             STORAGE - TRANSFER
2Q32 SULFONATION
2033 SULFONATION

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AI rOHOL*!
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                                                                                           WATER



                                                                                           CAUSTIC
                                                                                           SULFONIC
                                                                                           ACID
                                         CONDENSATE
                                         203206
                 CONDENSATE
                 203217
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       203301
                                      1	
                                           WASHOUTS 203202
                               WASHOUTS 203302
                                            FIGURE   11

-------
                               204 SULFAMIC ACID SULFATION
ALCOHOLS-
ETHOXYLATES-
SULFAMIC ACID-
               2041  RECEIVING
                    STORAGE-TRANSFER
2042 SULFATION
                  LEAKS, SPILLS, STORM
                  RUNOFFS, WASHOUTS.
                  204102
                                                  SOLVENTS
                                                                                     "WATER

                                                                                     •CAUSTIC
                                                                                      AMMONIUM ALKYL
                                                                                      SULFATES
           WASTEWATER
           2O4201
                                                                WASHOUTS
                                                                2O42O2
                                             FIGURE   12

-------
                               205  CHLOROSULFONIC ACID SULFATION
                    205?  RECEIVING
                        STORAGE-TRANSFER
                                                                2052 SULFATION
CHLOROSULFONIC ACID
ALCOHOLS
ETHOXYLATES
                       LEAKS, SPILLS, STORM
                       RUNOFFS, WASHOUTS.
                       205?02
                                                                                        WATER

                                                                                        CAUSTIC
^ ALKYL SULFURIC ACID ESTER
  TO NEUTRALIZATION
                                               FIGURE  13

-------
water of sulfation and generates pratically  no  side  reactions.
It is a corrosive agent and generates HC1 as a by-product.

An  excess  of about 5 percent chlorosulfonic acid is often used.
It will yield an inorganic  salt  upon  neutralization  which  is
undesirable  in  some  applications  as  it  can  result  in salt
precipitation in liquid formulations, etc.
NEUTRALIZATION OF SULFURIC ACID_ESTERS
AND SULFONIC ACIDS "(206)

This step is essential in the  manufacture  of  detergent  active
ingredients;  it  converts  the acidic hydrophylic portion of the
molecule to a neutral salt.

Alcohol sulfates are somewhat more difficult to  neutralize  than
the  alkylbenzene  sulfonic  acids  due  to  the  sensitivity  to
hydrolysis  of  the  alcohol  derivative.    For   this   reason,
neutralization  is  usually  carried  out  at a pH above 7 and as
rapidly as possible.

This is not a  difficult  feat  for  those  who  neutralize  con-
tinuously,  but  it  is more of a problem for the batch processor
unless he has excellent stirring.

As a result of hydrolysis occurring in the  neutralization  step,
there  will  be some free alcohol generated which would be picked
up in the oil and grease analysis.  As a product this is not  all
bad  since  the  free  alcohol  can actually be considered a foam
stabilizer in some situations.  If used in heavy  duty  products,
the alcohol tends to be lost in the spray tower.

SPEAY DRIED DETERGENTS (207)

This  is another critical area of detergent manufacture.  In this
segment of processing, the neutralized sulfonates and/or sulfates
are brought to the crutcher where they are blended with requisite
builders and additives.  From here the slurry is  pumped  to  the
top of a spray tower of about 4.5 - 6.1 m (15 - 20ft) in diameter
by  45  -  61m (150 - 200 ft) high where nozzles, around the top,
spray  out  detergent  slurry   of   approximately   70   percent
concentration.

A  large  volume of hot air enters the bottom of the tower rising
to meet the falling detergent.  For low density products, hot gas
and powder flow concurrently downward.

This step is critical in that  the  detergent  particles'  shape,
size  and density are determined by all of the design preparation
made previously,  and the shape and  size  in  turn  will  largely
determine dusting and the solubility rate of the detergent itself
in the washing process.
                                45

-------
               206  NEUTRALIZATION OF SULFURIC ACID ESTERS AND SULFONIC ACIDS
                 206; RECEIVING
                     STORAGE-TRANSFER
206? LIQUID NEUTRALIZATION
                                                                           2063 DRY NEUTRALIZATION
ACIDS:
 SULFURIC ACID ESTERS
 SULFONIC ACIDS
BASES	

OTHER INGREDIENTS:
 WATER; SOLVENTS;
 HYDROTROPES.
 ADDITIVES
WATER ACIDS -
CAUSTIC
LIQUID PRODUCTS
AND SLURRIES TO
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206302

                                                FIGURE  14

-------
The  air  coming  from  the tower will be carrying dust particles
which  must  be  essentially  eliminated  to  meet  air   quality
standards.

Due  to  product  change and buildup of combustible deposits, the
spray towers  are  periodically  shut  down  and  cleaned.   This
practice  varies  from  two  or three times a week to once in two
weeks or longer.  One thing that all tower  operations  share  is
the  cleaning  process.   First,  the  easily  available material
sticking to the tower walls is scraped to be recycled if  at  all
possible, or sent to solid waste.

Men  are  sent into the tower with abrading equipment to continue
the dry cleaning process.  Here again,  the  product  is  usually
preserved for reuse or disposed of as a solid waste.

Finally,  the tower is thoroughly washed down by spraying streams
all over the inside surface.  The final step is  mandatory  since
the  detergent  manufacturers  must  be very careful to avoid any
mixing of any  phosphate-nonphosphate  formulations,  white  with
colored systems or anionic with nonionic formulations.

The  mixing  problem is compounded somewhat by the fact that some
detergent manufacturers custom process for a variety of marketers
which requires more frequent spray tower "turnaround".

Waste water streams are rather numerous  (see  accompanying  flow
sheet for process).  They include many washouts of equipment from
the  crutchers  to  the spray tower itself.  One waste water flow
which has high loadings is that of the air scrubber which  cleans
and  cools  the  hot gases exiting from this tower.  This is only
one of the several units  in  series  utilized  to  minimize  the
particulate matter being sent into the atmosphere.

All  of  the  plants  recycle  some of the waste water generated.
Some of the plants recycle all of the flows generated.

Due to increasingly stringent air quality  requirements,  we  can
expect  that  fewer  plants  will  be able to maintain a complete
recycle system of all water flows in the spray  tower  area.   In
the case of the fast "turnaround11 tower, they, too, are unable to
utilize all of their scrubber and other wash waters.

After the powder comes from the spray tower it is further blended
and  then  packaged.   Solid  wastes  from  this area are usually
recycled.

LIQUID DETERGENTS (208)

Sulfonated  and  sulfated  products,  as  produced  in  processes
described  in  201   - 206 are pumped into mixing tanks where they
are blended with numerous ingredients, ranging from  perfumes  to
dyes.   From  here,  the fully formulated liquid detergent is run
down to the filling line.

-------
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                                                 207SPRAY DRIED DETERGENTS
  2071 RECEIVING
      STORAGE-TRANSFER
                                           2072 CRUTCHING
                                                                                  2073 SPRAY DRYING
                                                                                                                      2074 BLENDING AND PACKAGING
 ACTIVES:
   LAS SLURRY; ALCOHOL
   SULFATE SLURRY;
   ETHOXYLATES
  BUILDERS:
   PHOSPHATES: SILICATES:
   CARBONATES; SULFATES.
   BORATES
  ADDITIVES:
   AMIDES: SOAPS; FLOOR
   ESCENT WHITENESS;
   PERFUMES; DYES: PER-
   BORATE: CMC: ANTICAKING
   AGENTS: ENZYMES
        WASHOUTS
        207102
                                                                   FIGURE   15

-------
The filling line usually consists of a long conveyor which passes
many stations.  Each station  performs  a  given  task,  such  as
filling,  capping,  checking  weight, labeling, etc.  Often, soap
solutions are used to lubricate the conveyor so that the  bottles
flow smoothly past the various stations.

Whenever  the  filling  line is to change to a different product,
the filling system must  be  thoroughly  cleaned  out.   This  is
equally  true  of  the mixing equipment.  Properties of differing
products are often so contrasting that there  must  be  no  cross
contamination; otherwise the performance and other specifications
cannot  be  met.   To avoid this problem the mixing equipment and
all filling plumbing is thoroughly flushed with  water  until  it
runs clear.

PRYa DETERGENT BLENDING J209J

Fully  dried  "active"  (surfactant)  materials  are blended with
additives, including  builders,  in  dry  mixers.   In  the  more
sophisticated  plants  mixing  time is utilized to the maximum by
metering components into weighing  bins  prior  to  loading  into
mixers.   When  properly  mixed,  the  homogeneous dry product is
packed for shipment.

Normal operation will see many succeeding  batches  of  detergent
mixed  in  the  same equipment without anything but dry cleaning.
This procedure is followed  until  the  next  formulation  to  be
blended  must  not be contaminated with even an almost negligible
amount of the previously prepared  product.   At  this  time  the
equipment must be completely washed down.

For  this  reason, a modest amount of waste water is required for
the blender to maintain specification requirements.

The products fulfill a wide variety of industrial  cleaning  uses
from  dairy  cleaning  to box car washing.  They are also used to
some extent in household products.

DRUM DRIED DETERGENTS (210)

Drum drying of  detergents  is  an  old  process.   Much  of  the
equipment  still  in  use  is  well  over  thirty years old.  The
process yields a fairly friable product which  can  become  quite
dusty with any extensive handling.

There  are  several types of drum driers; those which have double
rotating heated drums with liquid  feed  coming  onto  the  space
above  and  between  the rolls, and a twin-drum dryer with dip or
flash feed.  The dip feed is a pan in which the "bottom"  of  the
roll or drum picks up material to be dried.

The  thin  layer  is  removed  continuously by a knife blade onto
conveyors.  The powder is substantially  anhydrous.   The  vapors

-------
                                     208 LIQUID DETERGENT MANUFACTURE
                       2081 RECEIVING
                           STORAGE-TRANSFER
           2082 BLENDING
                                              2083 PACKAGING
ACTIVES:
 LAS; SULFONIC ACID;
 ETHER SULFATES;
 OLEFIN SULFONATES;
 ETHER SULFONATES;
 AMINE OXIDES; AMIDES
BUILDERS:
 PHOSPHATES; SILICATES
ADDITIVES:
 HYDROTROPES;
 SOLVENTS; COLOR;
 PERFUME
WATER.
                                  BULK
                                 • DETERGENT
                                  SALES
                                                  PACKAGING
                                                  EQUIPMENT
 CASE GOODS
"TO WAREHOUSE
WASHDOWN
208212

HEELS
208213
                        FIGURE   16
               WASHOUTS
               2O8202
CONTAINER
WASHINGS
2O8310


SOLID WASTE
2083O9

LEAKS, SPILLS,
WASHOUTS
208302


-------
                           209 DETERGENT MANUFACTURE BY DRY BLENDING
                   2097
ACTIVES:
 LAS SLURRY; FLAKES;
 BEADS; SULFONIC ACID;
 AMIDES; ETHOXYLATES

BUILDERS:
 SILICATES; CARBONATES;
 PHOSPHATES; BORATES

ADDITIVES:
 CMC; ANTICAKING AGENTS;
 COLORS; PERFUMES;
 ABRASIVES; DIATOMACEOUS
 EARTH; PUMICE
                       RECEIVING
                       STORAGE-TRANSFER
2092 DRY BLENDING
                                                                                      2093 PACKAGING











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                                                           TO WAREHOUSE
                                                   SOLID WASTE
                                                   209209
                                           SOLID WASTE
                                           209309
                                                   WASHOUTS
                                                   209202
                                            WASHOUTS
                                            209302
                                               FIGURE   17

-------
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                                   210 DRUM DRIED DETERGENT
              2101 RECEIVING
                 STORAGE-TRANSFER
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                                 2103 PACKAGING

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                             210201
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210202
WASHOUTS
210302
                                           FIGURE  18

-------
coming  off  are often collected and removed through a vapor head
between the drums.

The rolls of a drum dryer are often 0.6-1.8m  (2  -  6  ft)  in
diameter  and 0.9 - 4.5 m (3 - 15 ft) long with revolution speeds
of 5 - 10 rpm.  About 6-15 seconds residence time  is  provided
the  slurry  on  hot metal surface which is short enough to avoid
degradation of heat-sensitive products.

As an example of the limitations of drying capacity, the capacity
of the drum varies between 4.5 and 48.8 kg  of  finished  product
per  sq meter of drying surface per hour (between 1 and 10 Ib per
sq ft per hour).

This operation should be essentially free of generation of  waste
water discharge other than an occasional washdown.

DETERGENT BARS AND CAKES (2111

In  answer  to  the  need  for a "bar soap" which performs satis-
factorily in hard water, the detergent industry manufactures  and
markets  detergent bars.  They constitute about 20 percent of the
toilet bar market.

There are two types  of  "detergent"  bars;  those  made  of  100
percent   synthetic   surfactant  and  those  blending  synthetic
surfactant with soap.   Most products are of the latter type.

Once the active  ingredients  have  been  manufactured  they  are
blended  in  essentially  the  same manner and in similar type of
equipment used for conventional soap.

Due to the sensitive nature of  the  surfactant  portion  of  the
detergent  bar,  fairly  frequent  cleanups,  including equipment
washdowns, are required.  Otherwise thermally degraded surfactant
will contaminate the bar leading to such  undesirable  properties
as stickiness and off-color.

FORMULATIONS


Soaps,  detergents,  and  cleaning  agents  -  some of the latter
containing specific ingredients for specified cleaning purposes -
contain a wide variety of chemical compounds  to  carry  out  the
functions of the cleaning process involved.  In the case of soap,
the  sodium  or potassium salts of a range of fatty acids, having
carbon numbers of 8 to 22,  constitute the principal surfactant or
cleansing agent.  In addition,  there is a certain amount of salt,
NaCl, included in soap to  perform  the  function  of  having  an
electrolyte   present,  which  increases  diffusion  and  surface
orientation, by ion reactions.   Glycerine,  itself, is often  left
in  the  soap,  or  purposely  added,  for  its general effect in
promoting a feeling of  softness  and  slipperiness,  the  latter
                                53

-------
                                  217 DETERGENT BARS AND CAKES
           2111 RECEIVING          2112 MIXING
              STORAGE-TRANSFER      WORKING-CONDITIONING
                                                                          2113  STAMPING-PACKAGING
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                                                                                211302
                                                                                                          BAR
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                                                                                                          TO
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                                                                                                          DETERGENT
                                                                                                          CAKES
                                                 FIGURE   19

-------
feature being one that leads the user to thoroughly wash off soap
residue, especially in personal use.

In  the  case  of  a  typical  all-purpose household detergent, a
general average of  approximately  ten  chemical  components  are
included  in  a  typical  formulation.   All these compounds have
definite  functions  to  produce  a  balanced   detergent.    The
principal   component,  of  course,  is  the  surfactant  itself,
typically an alkyl-aryl  sulfonate,  a  sulfate  salt  of  lauryl
alcohol, and various types of sulfates or sulfonates derived from
ethoxylated  alcohol  or  of  other aromatic compound sulfonates.
The  surfactant  itself  is   largely   effective   in   reducing
interfacial  tension  between  the surface to be cleansed and the
soil deposit itself.  Typically, detergents contain approximately
5-30 percent of such surfactant active-ingredient material.

An important  ingredient  in  detergents,  at  least  up  to  the
present,  is  the  radical phosphate, PCW, which is included in a
variety of forms, discussed later.  The function of the phosphate
is that of a disperser, a suspender, an emulsifier, and a  buffer
to reduce the general alkalinity of the surfactants and produce a
detergent  in  the  pH range of 7.0 - 9.0.  The phosphate ion has
been an important multiple functioning ingredient in  detergents.
If  it  is  reduced  by laws, these functions of a detergent will
have to be handled by  other  compounds  that  then  need  to  be
included  in  a  formulation.   Another major constituent of most
detergents is an  inorganic  salt.   Most  typically,  these  are
either  in  the  form of sodium sulfate and, occasionally, sodium
chloride or other added  inorganic  salts.   In  detergents  they
serve the purpose of diminishing the interfacial tension, partic-
ularly  that  between water, carrying the detergent, and the soil
deposition to be removed.  They also act for  this  reason  as  a
disperser of the soiling.  Additionally, an important function is
to  provide  an  electrolyte; i.e., an ion content which enhances
and  accelerates  the  interchange  and  surface  orientation  of
wetting  and  organic solubilizing portions of a molecule.  These
inorganics are usually present up to  about  20  percent  in  the
typical formulated detergent.

Methyl  cellulose,  in amounts of about 1 percent, are present in
many  detergent  formulations  to  reduce  redeposition  of   the
soiling,  once  it  has  been  removed  from  the soiled surface.
Silica, in various forms, but  usually  in  the  form  of  sodium
silicate,  to an extent of 5 percent or less, is included in many
formulations to minimize the corrosion  of  metals,  particularly
those  present  in  a  drum  liner  or  other  washing  container
surfaces.   Fatty  acids,  such  as  are   used   in   the   soap
manufacturing  process by neutralization, are added up to a range
of about 3  percent,  largely  to  enhance  foam  stability  and,
therefore, to prevent an over-use of the detergent in the washing
solution.   The  borates  are  also generally added, often in the
form of sodium perborate.  These borate compounds are added up to
an extent of 10 percent, and serve the  purpose  of  bleaching  a
fabric  and/or  removing  stain  deposits  of  soiling on textile
                                 55

-------
surfaces.  In  addition  to  these  components  there  are  often
perfumes  added,  as well as anti-oxidants.  Dyes are often added
as brighteners, even fluorescent dyes, so that  the  reflectivity
of  the surface is enhanced, making it look brighter.  Obviously,
the perfumes are to give a more pleasing  odor  and  aroma.   The
anti-oxidants  are added, particularly when there are fatty acids
in the composition, to avoid a noticeably rancid odor.

In general, cleaning compounds contain far more of the  inorganic
salt  compounds,  which  are  more efficacious in cleaning duties
against surfaces such as dishware, flooring, and in the  cleaning
of  machine  parts,  after  oil  has  been  used  during  lathing
operations.  Thus, a typical floor cleaning formulation  contains
as  much  as 60 percent of sodium silicate, as much as 10 percent
of  phosphates,  in  the   form   of   tri-polyphosphate,   also,
occasionally   the  tetravalent  potassium  pyro-phosphate.   The
surfactant in such cases is usually an  alkyl-aryl  sulfonate  to
make  up  the  balance  of  the  composition.   Hand  dishwashing
detergents contain active ingredients such as  amine  oxides  and
sulfated  ethoxylated  lauryl  alcohols.   The industrial machine
dishwasher products are compounded  as  high  as  50  percent  by
weight  sodium  tri-polyphosphate, another 25 - 50 percent sodium
metasilicate (anhydrous) and a minor amount 2-5 percent organic
surfactant.

Sodium  carbonate,  present  either  as   the   normal   divalent
carbonate,  or  as the sesqui-carbonate, in amounts ranging up to
10 percent, is commonly  used.   Again,  a  tri-polyphosphate  is
included  to the extent of UO percent or up to the balance of the
detergent, if it is a powder.

Of all the functions,  mentioned  earlier  with  respect  to  the
compound, illustrating the functions, the main purpose of a soap,
detergent  or cleaning agent must be to loosen occluded soils and
to suspend it so that it does not  redeposit.   Accordingly,  the
basic  principle  of  the surfactant, even as soap itself, is the
lowering  of  the  interfacial  tension   between   the   systems
consisting of the fabric or surface to be cleaned and the soiling
on   that   surface.    Frequently  the  surfactant  function  is
accomplished by components  which  also  reduce  the  interfacial
tension between the water in the system, and the air.  This leads
to  high  foaming  compositions  which are not useful in actually
cleaning and removing the soiling depositions.

In the case of soap, now used mostly for personal body care,  the
main  function  is  that  of  interfacial  separation,  from  the
epithelial or skin surface and the soiling, which can be produced
by the body  itself,  as  well  as  from  extraneous  particulate
matter,  oils and greases.  The main components of the body's own
soiling are  those  of  the  fatty  acid-esters  which  range  in
composition  from  carbon numbers C5 up to C37.  The compounds of
lower  molecular  weight  are  generally  the  fatty  acid  salts
themselves  or  the  fatty acid esters of these salts.  The other

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main soil components  ar
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                           SECTION IV

                     INDUSTRY CATEGORIZATION

Introduction

There  are  several ways in which the soap and detergent industry
could be categorized.   While  each  may  have  its  own  special
rationale,  the  search was for the system of categorization that
would best identify potential waste water sources  and  controls,
provide  a  permit  granting  authority  with  a way to analyze a
specific  plant  regardless  of  its   complexity,   and   permit
monitoring  for compliance without undue complication or expense.
The systems examined included  categorization  by  raw  materials
used,   wastes   discharged,   finished   products  manufactured,
processes employed, and plant size or age.

Systems based solely on raw materials used, wastes discharged, or
finished products manufactured are either overly complex, even if
based on generic chemical groups, or highly arbitrary if  greatly
simplified.   This  is true in respect to both categorization and
monitoring  for  compliance.    Furthermore,   they   take   into
consideration  only  the potentials for waste generation that are
inherent in the nature of the  materials  (e.g.,  boiling  point,
solubility, etc.) and ignore the potentials of other factors such
as processes employed.

The  operations  of  the  soap  and  detergent  industry  may  be
considered  to  consist  of  application  of  processes  to   raw
materials  for  production  of  intermediates,  which in turn are
subjected to further processing to  arrive  at  the  finished  or
marketed  products.   There  is  an  intimate relationship within
chains of raw materials, intermediates,  processes  and  finished
products  with  the processes employed being the key to obtaining
the finished products from the raw materials.  Thus, a system  of
categorization  based  on  processes  reflects all variables that
affect raw waste discharges.

Plants employing specific sets of processes tend  to  be  of  the
same  general age and the principal effect of age is reflected in
the processes utilized  (e.g.,  kettle  boiling  of  fats  versus
continuous  neutralization  of fatty acids for production of neat
soap), not in  the  level  of  raw  waste  load  generated  by  a
particular  set of processes.  Moreover, the determination of age
is complicated by extensive repair  and  replacement  of  process
units.   For  example,  what is the age of a large kettle boiling
facility originally constructed 50 years ago,  but  in  which  an
average  of one kettle has been reconstructed every two years for
the past thirty years?  What is the age of a spray  drying  tower
constructed  in 1930 for manufacturing soap granules, modified in
1946 for production of spray dried detergents, and  subjected  to
periodic  replacement  of  working  parts since modification?  In
view of the foregoing, age of plants is not considered  to  be  a
practical basis for categorization.
                                 59

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Plant  size  as  a  basis for categorization is even more complex
than evaluation of age.  Some independents have relatively  small
plants that in complexity of processes employed equal the largest
plants  of the major international companies.  A relatively small
operation consisting of a single process chain (e.g.,  production
of  bar  soaps  utilizing fatty acid neutralization) may equal in
size the comparable segment of the largest complex  plant.   Size
of  plant may be the result of difference in the physical size of
individual units of equipment or the number of units of the  same
physical  size.   Thus, categorization based on size would result
in an unmanageable welter of categories, with  many  representing
only one or a very few plants.

Though  plant  size  cannot  be  used  as  a  basis  for  orderly
categorization,  and  thus  is  not  reflected  in  the  proposed
guidelines  and standards, there are factors generally associated
with size that should be considered.  The complexity of  a  plant
(i.e., number of processes and products) is frequently associated
with  size,  the  small  plants  tending  to  be  more limited in
diversity.  This may curtail the ability of a small plant to work
off a by-product or waste as a feed material for other processes.
Similarly, the limited volume of a  waste  produced  in  a  small
plant   may   prohibit  installation  of  by-product  utilization
processes (e.g., use of nigre from kettle boiling for manufacture
of pet soaps and  soap-based  lubricants)  on  a  scale  that  is
economically viable.

Categorization

The  categorization  consists  of  two  major  categories  and 19
subcategories.  The major categories follow the natural  division
of  soap  manufacturing   (production  of  alkaline metal salts of
fatty acids derived from natural fats  and  oils)  and  detergent
manufacturing  (production  of  sulfated  and sulfonated cleaning
agents  from  manufactured  raw  materials,  primarily  petroleum
derivatives).    The   subcategories   are   based   on  discrete
manufacturing units employed by the industry  for  conversion  of
raw   materials  to  intermediated  products  and  conversion  of
intermediate   products   to   finished/marketed   products.    A
manufacturing unit may contain a single process  (e.g., continuous
neutralization   for  production  of  neat  soap  by  fatty  acid
neutralization)  or  a  number  of  processes  (e.g.,  crutching,
drying,  milling, plodding, stamping and packaging for production
of bar soaps from neat soap).

Several advantages result from the categorization.   It  accounts
for  the  variable effects on raw waste loads attributable to raw
materials, processes and finished product.  The potential sources
and natures of waste waters are readily discernible, as  are  the
potential  in-plant  control  measures.  It is amenable to use in
development of permits irrespective of the complexity of a plant.

The subcategories are as follows:
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                            SOAP MANUFACTURE

 Soap Manufacture by Batch Kettle  (101)*
 Fatty Acid Manufacture by Fat Splitting  (102)
 Soap Manufacture by Fatty Acid Neutralization  (103)
 Glycerine Concentration  (104A)
 Glycerine Distillation (104B)
 Soap Flakes and Powders  (105)
 Bar Soaps (106)
 Liquid Soap (107)

                           DETERGENT MANUFACTURE

 Oleum Sulfonation and Sulfation (Batch and Continuous)  (201)
 Air-SO3_ Sulfation and Sulfonation  (Batch and Continuous)  (202)
 SO3 Solvent and Vacuum Sulfonation (203)
 Sulfamic Acid Sulfation  (204)
 Chlorosulfonic Acid Sulfation (205)
 Neutralization of Sulfuric Acid Esters and Sulfonic Acids  (206)
 Spray Dried Detergent  (207)
 Liquid Detergent Manufacture  (208)
 Detergent Manufacturing by Dry Blending  (209)
 Drum Dried Detergents  (210)
 Detergent Bars and Cakes (211)

*The  numbers  shown  after  the   subcategories   are   used
throughout      the      report      to      identify     the
subcategories/processes.

Three of the subcategories have  been  further  segmented   in
recognition  of  the  added  waste generation that may result
from specific types of operations.   A  separate  segment  has
been   established  under  fatty  acid  manufacture  for  the
hydrogenation  of  the  fatty  acids  to  accommodate   those
facilities   employing   hydrogenation.   Under  spray  dried
detergents  three  segments  have  been  designated;   normal
operation,   air   quality   restricted  operation  and  fast
turnaround operation.  The latter two produce much more waste
water than the former and thus cannot effect the same  degree
of recycle of waste water to process.  A separate segment has
been  established within the liquid detergent subcategory for
fast turnaround operation involving automated fill  lines,  a
phenomenon  closely  associated  with  the  small producer  of
liquid household detergents.
                               6l

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                              SECTION V


                       WASTE CHARACTERIZATION

INTRODUCTION
Numerous organic and inorganic chemical compounds are used in the
manufacture of  soaps  and  detergents.   As  the  reactions  are
carried  out  some of these materials and their derivatives enter
the waste waters from the processing steps.  These materials  are
then  treated  as  contaminants  and  processed as waste water in
conventional  waste  treatment  units.   In  discussion  of   the
individual  unit processes that follow, the sources and nature of
waste waters are presented in some detail. The numbers associated
with the processes and waste streams are  keyed  to  the  process
flow sheets. Figures 1 through 19.

SOAP MANUFACTURE BY BATCH KETTLE —  (PROCESS 101)


Introduction

Effluents  of this process arise from three sources.  Handling of
fats and oils results in leaks and  spills  (streams  101102  and
101202).   These  are  usually  collected with water and the fats
skimmed.  Pretreatment of the fats or  oils  results  in  process
waste  waters  101321 and 101218.  Soap making results in two by-
products, 101319 and 101320, which generally are disposed  of  as
waste  waters.   These  streams  are  discussed  in detail in the
following sections.

Water and Waste Water Balance

Water for this process will usually come from  municipal  systems
since  the  plants  are  old  and  somewhat  isolated.   For  the
barometric condenser (101218)  surface  water  or  cooling  tower
water  will  be used.  Since steam is used for heating the fat in
both pretreatment  and  saponification,  some  process  water  is
introduced in this manner.

Kettle  boiling  soap  is  a  batch process and water use will be
intermittent.  Instantaneous flows of 0.12-18.9 I/sec  (2-300gpm)
will  be  experienced.    overall  water use can be limited to 623
1/kkg (75 gal/1000 Ib)  of soap, but as much as  2080  1/kkg  (250
gal/1000 Ib)  is used.

Water  reuse and recycle is not common in kettle boil soap plants
for process water.  Where a barometric condenser is used for  the
steaming  pretreatment  step,  recycle through a cooling tower is
sometimes used, but even  here  use  of  surface  water  is  more
common.    Except  for the barometric condenser, all water use can
be considered process water.
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With reasonable  water  conservation,  and  excluding  barometric
condenser  water,  total  waste water discharge should not exceed
2080-2500 1/kkg  (250-300 gal/1000  Ib)  for  all  steps  included
within  the subcategory.  Inclusion of barometric condensers with
recycle  through  cooling  towers  and  limited  blowdown   would
approximately double the volume of discharge.

Specific  waste  water  sources  and  constituents  are discussed
generally and specifically tabulated in the next section.

Wa s t e Water constituents

Leaks, spills and storm runoff or floor washing  (streams  1C1102
and  101202)  are  invariably  collected for recovery of fats and
oils by settling and skimming in fat traps.  The waste water will
contain some emulsified fats, since the skimmers and settlers  do
not operate at 100 percent efficiency.

The  fat  pretreatment  is carried out to remove impurities which
would cause color arid odor in the  finished  soap.    Acid  and/or
caustic  washing  may  be  used.  This results in sodium soaps or
sulfuric  acid  solutions  of  fatty   acids   (101231).    Other
pretreatment  steps  make  use  of  proprietary chemical formulas
which result in water containing the treatment  chemicals,  fatty
impurities  and emulsified fats.  Clay and carbon treatments give
solid wastes and do not directly result in aqueous effluents, but
steam is used for heating and the  condensate  must  be  removed.
Often  a  barometric condenser is used, and there is carryover of
low molecular weight fatty acids (101218).

Waste waters from the fat skimmer and from the pretreatment steps
each contribute about 1.5 kg of BOD5 per 1000  kg  of  soap  (1.5
lb/1000  Ib) .   Concentrations typically are 3600 mg/1 BOD5, 4267
mg/1 COD, 250 mg/1 of oil and grease with a pH of 5.

Saponification of the fats  and  oils  by  sodium  hydroxide  and
salting   out   of  the  soaps  (graining)  with  salt  does  not
necessarily lead to any effluent.  The  nigre  which  comes  from
washing  excess  salt  and  impurities  from  the  neat soap with
aqueous caustic is always recycled to some extent.    The  organic
portion consists of low grade soap.  In some plants, the nigre is
acidified to convert the soaps to fatty acids which are recovered
for  sale.   Although  acidification  removes much of the organic
contaminant, some  is  still  discharged   (101320).   Some  manu-
facturers' third alternative for the nigre is the sewer  (101319).

The  stream  referred to as sewer lyes (101319) arises most often
from the reclaiming of scrap soap.  The lye and salt water  added
to  separate the soap must be discarded because it contains paper
and other dirt.

Sewer lyes and nigre are  concentrated  waste  waters   (in  mg/1)
alkalinity  up  to  32,000,  BOD5  as  high  as 45,000, COD up to

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64,000, chlorides of 47,000 and a pH of 13.5.  Volumes,  however,
are small - 249 1/kkg of soap  (30 gal./1000 Ib).

FATTY ACIDS BY FAT SPLITTING— JPRQCESS 102)
Introduction

In  this  process, fats and oils are converted to fatty acids and
glycerine by hydrolysis with water.  In Section 103 conversion of
fatty acids to soap is considered  and  Section  104  deals  with
glycerine  recovery.   There  are  two  process condensates which
contain  organic  contaminants  -  (102322  and  102418).   Also,
treatment of the fatty acid still bottoms results in contaminated
water (1C2423).  Since streams from fat pretreatment (102221) and
leaks  and  spills  are essentially the same as analogous streams
(101102 and 101202) in Process 101, the discussion  will  not  be
repeated.

Fatty  acids  from the fat splitting frequently are given a light
hydrogenation (usually employing a nickel catalyst)  to  eliminate
polyunsaturation  in the acids.  The only waste water coming from
this step is that arising from equipment cleanouts.


Water and Waste Water Balance

In general fatty acid plants are relatively  new  and  contain  a
water  recycle  system.  The small amount of clean water required
will come  from  surface  water,  municipal  systems,  or  wells.
Although   operation   of   surface   condensers  and  barometric
condensers requires thousands of  gallons  per  minute,  blowdown
from fatty acid plants ranges from 3.2-12.6 I/sec (50-200gpm).

The other main contaminated stream is from treating still bottoms
(102423).  It is smaller, but highly contaminated.

Cleanouts of hydrogenation equipment are infrequent and the total
volume  of  water  is  small.   Potable water is used to preserve
cleanliness.

With adequate water conservation, including recycle of barometric
Condenser  water,  total  discharge  should  not  exceed  600-700
gal/1000 Ib of anhydrous product in contrast to the present range
of 400-23,000 gal/1000 Ib.
Waste Water ^constituents

See  Process  Section  101  for discussion of 102102, 102202, and
102402 which are  waste  waters  from  leaks,  spills  and  storm
runoff.   Also,  fat  pretreatment  wastes  102205 and 102224 are
covered under Process 101 for the analogous streams.

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Process condensate 102322 from fat splitting will be contaminated
with volatile  low  molecular  weight  fatty  acids  as  well  as
entrained  fatty  acids  and  glycerine  streams.  The barometric
condensate 102418 will also contain volatile fatty acids.   These
streams will be settled and skimmed to remove the insoluble fatty
acids  which  are  processed  for sale.  The water will typically
circulate through  a  cooling  tower  and  be  reused.   To  keep
emulsified and soluble fatty material at a reasonable level, part
of  the  stream  is  purged to the sewer.  This blowdown (102204,
102304, 102404) contributes about 10 kg of BODS and 18 kg of  COD
per  kkg  (10  Ib  BOD5  and  18  Ib  COD/1000~lb)  of fatty acids
produced plus some oil and grease.

Treatment of stream 102423 consists of acidification to break the
emulsion and skimming of insoluble fatty acid pitch.   The  waste
water  is  neutralized  and  sent to the sewer.  This waste water
will contain salt from  the  neutralization,  zinc  and  alkaline
earth  metal salts from the fat splitting catalyst and emulsified
fatty acids and fatty acid polymers.  One plant had about 0.6  kg
of  BODJ5  and  0.9 kg of COD/kkg  (0.6 Ib BOD5 and 0.9 Ib COD/1000
Ib)  of fatty acids from this source.

Fatty acids and a modest amount of nickel  soaps  constitute  the
bulk  of  contaminants from hydrogenation.  Very small amounts of
suspended nickel may be present.


SOAP BY FATTY ACID NEUTRALIZATION — (PROCESS 103)

Introduction

This process is relatively simple and high purity  raw  materials
are  converted  to  soap with essentially no by-products.  Leaks,
spills, storm runoff and washouts are absent.  There is only  one
waste  water  of  consequence.  It is 103326, the sewer lyes from
reclaiming of scrap.   Stream  103224  is  generally  nonexistent
since there is a net consumption of brine in the process.

Water and Waste Water Balance

Except  for  the small amount of water (258 1/kkg;  31 gal/1000 Ib
of soap)  used for reclaiming scrap and  resulting  in  the  sewer
lyes,  the  process  produces no other aqueous effluent.  Potable
water is fed into the process.

Waste Water Constituents

The sewer lyes (103326) will contain the excess caustic soda  and
the  salt  added  to grain out the soap.   Also, they will contain
some dirt and paper not removed by the strainer.  Typically 3  kg
of  BOD5  and  5.5  kg of COD/1000 kg (3 Ib of BOD5 and 5.5 Ib of
COD/1000 Ib)  of soap will be discharged.

GLYCERINE RECOVERY —  (PROCESS 104)
                                 66

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introduction

The feedstock for this unit process comes from soap  boiling  and
fat  splitting processes 101 and 102.  Both crude glycerines will
contain about 90 percent water, but that from soap kettle boiling
will contain a fair amount of salt and some NaOH.   Both  streams
will  contain  soap  or  fatty acids which must be removed in the
pretreatment section by precipitation with alum and filtration.

There are three waste waters of consequence  from  this  process;
two  barometric  condensates,  from evaporation of water (104318)
and from distillation of glycerine (104418), plus  the  glycerine
foots  or  still bottoms (104428).  Contaminant of the barometric
condensates is essentially  glycerine  with  a  little  entrained
salt.   The  glycerine foots are water soluble and are removed by
dissolving in water.

Glycerine can also be purified by use of ion exchange  resins  to
remove  the sodium chloride followed by evaporation of the water.
This process puts additional  salts  into  the  waste  water  but
results in less organic contamination.

Water, and Waste Water Balance

Compared  with  the  amount  of  water  used  in  the  barometric
condensers, water used for other purposes is negligible.

Installations not recirculating cooling water through  a  cooling
tower  use  from  698,000-1,540,000  1  of water per kkg (84,000-
185,000 gal. of water per 1000 Ib)  of glycerine produced.  With a
cooling tower, blowdown consumes 9975 1/kkg (1200  gal./1000  Ib)
glycerine.

The  ion  exchange  process  is  reported  to  use  449 1/kkg  (54
gal/1000 Ib) of glycerine for both backwashing and regeneration.

The source of water for glycerine  recovery  is  usually  surface
water.   Since it is used mainly for condensing steam, quality is
unimportant.  Typically, a  plant  will  withdraw  water  from  a
river, put it through the barometric condensers, and discharge it
into the river with no treatment.

As  mentioned  above,  water  used  for washout of the still, for
steam generation and  the  ion  exchange  process  is  relatively
small,  generally  less  than  200 gal/1000 Ib.  These water uses
require treated water, usually from municipal supplies.  No water
is produced or consumed  in  the  process.   Approximately  60-70
percent  of the total water used is associated with the glycerine
concentration operation.

Waste Water Constituents

The two barometric condensers streams (104318 and 104418)  become
contaminated  with glycerine and salt due to entrainment.  stream
                                 67

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104428 is a water soluble by-product  which  is  disposed  of  by
washing   into  the  sewer.   It  contains  glycerine,  glycerine
polymers, and salt.  The organics will contribute  to  BOD5,  COD
and  dissolved  solids.  The sodium chloride will also contribute
to dissolved solids.  Little or  no  suspended  solids,  oil  and
grease or pH effect should be seen.

From the glycerine evaporator barometric condenser about 30 kg of
COD and 15 kg of BOD5 per kkg (30 Ib of COD and 15 Ib of BOD5 per
1000  Ib) of product will be discharged.  The foots and glycerine
still contribute about equal amounts of BOD5 and COD, 2.5 kg (2.5
Ib) and 5 kg (5 Ib) respectively per kkg (1000 Ib)   of  glycerine
produced.  Because the barometric condensers use large amounts of
water, concentrations are low.  The foots are diluted only enough
to remove them from the still, and concentrations of organics and
salts are about 30,000-400,000 mg/1.

SOAP FLAKES AND POWDERS — (PROCESS 105)


Introduction

In  this  process  the  neat  soaps from processes 101 or 103 are
converted to flakes or powders for packaging and sale.  The  unit
processes  produce  the  dry  soap  in the physical form desired.
There are a number of possible effluents shown on the flow  sheet
for  process  105.   However,  survey of the industry showed that
most  operating  plants  either  recycled  any  waste  water   to
extinction,  or  used  dry cleanup processes.  Occasionally water
will be used for equipment cleanup.

In converting neat soap to flakes, powder  or  bars,  some  scrap
results.  The flow sheets show scrap reclaim in processes 101 and
103.   There  is  an  aqueous  effluent  - sewer lyes - from this
reclaim operation  (streams 101319 and 103326).  All existing soap
plants  both  make  and  process  soap.   Therefore,  the   given
categorization  will handle the effluent sewer lyes under process
101 or 103.  Should a plant start with neat soap, the  sewer  lye
guidelines should be applied to 105.

BAR SOAPS —(PROCESS 106)
Introduction^

To  produce  soap  bars, neat soap is dried and physically worked
prior  to  extrusion  and  stamping.   Some  plants  have  filter
backwash   (106129),  scrubber  waters or condensate from a vacuum
drier (106201) and water  from  equipment  washdown   (106202  and
106302).

Waste Water Balance
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Water  from  drying neat soap is vented to the atmosphere.  Water
use by plants producing dry soap varies from none to  6230  1/kkg
 (750 gal/1000 Ib) of soap made.  The largest quantity is required
when  a  barometric  condenser  is  used  on the drier.  In those
operations  employing  barometric  condensers,  both  volume   of
discharge and level of contamination can be reduced materially by
installation  of  an  atmospheric  flash  evaporator ahead of the
vacuum drier.

Waste Water constituents

The contaminant of all waste waters is soap which will contribute
primarily to BOD5 and COD.  Concentrations of BOD5  and  COD  are
typically  1600  mg/1  and 2850 mg/1 respectively in the scrubber
 (106201)i which is the major  source  of  contamination.   Driers
contribute  from  0.3 - 0.7 kg/kkg (0.3 - 0.7 lb/1000 Ib) of soap
to waste waters.  Washouts of the filter and of equipment account
for the remainder to give an average process total  of  2  kg  of
BOD.5. per kkg (2 lb/1000 Ib) of dry soap.

LIQUID SOAPS —  (PROCESS 107)


Introduction

Production   of  liquid  soaps  consists  of  a  simple  blending
operation followed by filling of rather large containers   (drums)
for  sale.  According to manufacturers interviewed, there is very
little aqueous effluent.  Leaks and spills  can  be  recycled  or
handled  dry.   Washout between batches is usually unnecessary or
can be recycled to extinction.

Water Balance

Some water is used as a part of  the  liquid  soap  formula,  and
small  amounts   (16.6  1/kkg  of  dry soap or 2 gal /1000 Ib) are
occasionally used for cleanup.

Waste Water Constituents

The liquid soaps will contribute  to  BOD5,  COD,  and  dissolved
solids.   However, amounts are very small (0.1 kg BOD.5 and 0.3 kg
COD/k kg of product)  (0.1 Ib BOD5 and 0.3 Ib COD /1000 Ib) .

OLEUM SULFONATION AND SULFATION — (PROCESS 201)


Introduction

The principle raw materials for synthetic  detergent  manufacture
are alkylbenzenes, fatty alcohols and alcohol ethoxylates.   These
are   converted  to  surface  active  agents  by  sulfonation  or
sulfation and  neutralization  with  sodium  hydroxide  or  other
bases.   There  are  no  process  waste  waters  from  the  oleum

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sulfonation and sulfa-tion reaction, leaks,  spills  and  washouts
result  in  some highly acidic wastes (streams 201102, 2C1202 and
201302).  The oleum tank breathing scrubber  which  collects  SO3
vapors  during filling of the tank also contributes sulfuric acid
to the waste waters (201101).  Although cooling water is used for
the sulfonation, it is indirectly used to  cool  Freon  or  brine
systems and doesn't become contaminated.

Although  the  amount  of  acids  released  are  small,  both the
sulfuric and sulfonic acids are strong acids  and  small  amounts
can  give  a  pH of 1 - 2; therefore, neutralization of spills is
imperative.  Also, the sulfonic  and  sulfuric  acid  esters  are
surface  active  (MBAS) and contribute to BOD^ and COD.  Some oil
and grease can be expected from spills of organic raw  materials.
The pH will be very low.

Water and Waste Water Balance

Usually  leaks  from  pump  packing  glands  will be flushed away
continuously with small streams of water.  Little water is  used.
Because the water use is small, 100 - 2740 1/kkg (12-330 gal/1000
Ib)  of  surfactant,  potable water is generally used,  since the
oleum tank scrubber will only be used  when  the  tank  is  being
filled, little water is used here.

Since  sulfonation  is highly exothermic and temperatures must be
kept low to avoid charring, the cooling water for sulfonation  is
a  large  stream.   Well  water  or  municipal water is preferred
because of their low temperatures making the refrigeration  cycle
more  economical.   In  the more efficient operations the cooling
water is recycled through a cooling tower and  the  discharge  is
limited to blowdown.

Haste Water Constituents

Since the source of contaminants is leaks and spills, all the raw
materials and products may be present.  These are fatty alcohols,
dodecylbenzene,  sulfuric acid, dodecylbenzene sulfonic acid, and
the esters of sulfuric acid and alchohols.  These chemicals  will
contribute  acidity,  sulfate ion, MBAS, oil, BOD5 and COD to the
waste water stream.

Concentrations of contaminants will depend on the amount of water
used for washdown.  Amounts of contaminants  average  0.2kg   (0.2
Ib)  BOD5,  0.6 kg  (0.6 Ib) COD and 0.3 kg (0.3 Ib) MBAS per  1000
kkg (1000 Ib) of sulfonated product. The pH will usually be  very
low  (1-2)  unless  the  sulfonation  wastes  are commingled with
neutralization wastes.

AIR-S03 SULFONATION & SULFATION (PROCESS 202)


Introduction
                                 TO

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Anhydrous SO3_ is used to sulfonate aklylbenzenes and  to  sulfate
alcohols  and  alcohol  ethoxylates  converting  them  to surface
active agents.  The acids produced  are  neutralized  with  NaOH,
ammonia and other bases as described in process 206.

Because  of  the  hazardous  nature of anhydrous SO3, the systems
designed for its use are  essentially  leak-free.   However,  any
leaks  and  spills  will  end  up  in the waste waters.  The main
source  of  contaminated  waste  waters  are  by-products.    The
incoming air-SO3_ stream will be scrubbed with H2S04 and the spent
acid  purged  (202309).   The  effluent  gas  contains  entrained
sulfonic acid, sulfuric acid and SO2 (202301).

Another sizable  source  (202302)  of  contamination  comes  from
startup  and shutdown.  Plants that run 7 days per week, 24 hours
per day will obviously have much  less  contamination  from  this
source than plants that shut down more frequently.

Water Balance

A   considerable   amount  of  water  is  used  for  cooling  the
sulfonation reactor.  This  is  usually  a  clean  water  stream.
Approximately  249  1/kkg  (30  gal/1000 Ib) of water is used for
disposing of by-products in continuous processes.  Water  use  in
batch  operations  will  be  several  times  as great for washing
reactors and filters.  All of this  water  usually  goes  to  the
sewer.

Waste Water Constituents

Stream  202303 which receives startup slop will contain unreacted
alcohols, alcohol ethoxylates,  and  alkylbenzenes.   These  will
show  up  as  oil  and grease as well as BOD5 and COD.  The other
contaminated streams  (202102, 202202, 202309~~and 202301) as  well
as  202303  will  contain  sulfonic  and  sulfuric  acids.  These
materials affect MBAS, acidity, SO.U, dissolved solids,  BOD5  and
COD.

Concentrations  from the process were observed to range from 380-
520 mg/1 of BOD5 and 920-1589 mg/1 of COD.  The pH ranged from  2
- 7.  Source of the contamination comes from three streams; leaks
and  spills - 15 percent, scrubbers - 50 percent and startup slop
- 35 percent.

S03 SOLVENT AND VACUUM SULFONATION — (PROCESS 203)
Introduction

Compared to  the  Air-SO3_  process,  these  techniques  are  used
infrequently.    Usually   they  will  be  batch  operations  and
relatively small.  Leaks, spills and washouts will  be  the  main
source of contamination.  No data specific to these processes was
obtained  or  submitted,  but  it  is believed that effluents and
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contaminants  will  be  essentially  the  same  as  for   Air-SO3
sulfonation. Process 202.

Waste Water Balance

No  direct process water will be used, but a small stream will be
used for cleanup of leaks and  spills.   Cooling  water  will  be
indirect.   It  is  possible  that  operators will use barometric
condensers to maintain the vacuum and to strip solvent, which  is
usually  SO2..   If  barometrics  are used, there could be a large
volume effluent with low concentrations of MBAS, oil and sulfite.

Waste Water Constituents

Leaks and spills will consist  of  raw  materials  and  products.
These   will  include  alkylbenzenes,  alcohols  and  ethoxylated
alcohols;  sulfonic  acids  and  sulfuric  acid  esters.    These
constituents   will  contribute  BOD5,  COD,  acidity,  dissolved
solids, sulfate, sulfite oil, and MBAS to effluent waste waters.

SULFAMIC ACID SULFATION — (PROCESS 20
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washout  will  be the main source of organic contaminants.  Since
HCl is a by-product it may be absorbed in water  or  caustic  and
sent to the sewer.

Water and Waste Water Balance

The  only process water used is for absorbing HCl.  Cooling water
is non-contact and should remain uncontaminated.

Contaminants found in leaks and spills will be  the  alcohols  or
alkylphenol  and  alcohol ethoxylates used for feedstocks.  Also,
chlorosulfonic acid hydrolysis products  (HCl and  H21SOU)  can  be
expected, plus the sulfated surfactants.  The same materials will
be in the other waste waters.

Since  it  is  not  necessary  to  clean  out the reactor between
batches, raw waste loads will be  similar  to  other  sulfonation
processes;  i.e., S03-Air.  An average of 3 kg (3 Ib) of BOD5 and
9 kg (9 Ib) of COD per kkg (1000  Ib)  of  sulfated  product" was
found.   Sizable  amounts  of  acidity and chloride  (5 kg/kkg) (5
lb/1000 Ib) can also be expected if the HCl is sent to the sewer,
but many plants recover it and sell it as muriatic acid.

NEUTRALIZATION OF  SULFURIC  ACID  ESTERS  &  SULFONIC  ACIDS  —
(PROCESS 2J361

Introduction

This  process  is  used  to  convert  the sulfated and sulfonated
alkylbenzenes and alcohols to neutral salts.  Various  bases  are
used  depending  on  the  required  characteristics  of the final
surface active agent.  The dry neutralization process   (2063)  is
infrequently  used in the United States to make consumer products
falling within SIC 2841.  However, some industrial products  will
be   made  in  this  manner.   Most  salts  are  made  by  liquid
neutralization (2062).  Plants making neutralized products  range
from a small batch kettle of a few thousand kilograms capacity to
several million kilograms per day continuous process units.

Water and Waste Water Balance

Waste  waters  from  these plants come almost entirely from leaks
and spills, with washouts occasionally contributing  (206102  and
206202).  Indirect cooling water is used since the neutralization
is exothermic, but contamination should be very rare.  No process
water is involved.

Waste Water Constituents

All  of  the  anionic  surface  active  agents  used in soaps and
detergents will  be  found  in  these  waste  waters.   Also  the
inorganic  salts,  such as sodium sulfate, from neutralization of
excess sulfuric acids will be  found.   Alkylbenzene  sulfonates,
ether  sulfates,  alcohol  sulfates,  olefin sulfonates, with the
                                 73

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ammonium, potassium, sodium, magnesium  and  triethanol  ammonium
cations will be represented.

These   constituents  will  contribute  to  BOD5  and  COD,  MBAS
dissolved solids, Kjeldahl ammonium  nitrogen,  sulfate,  acidity
and alkalinity.

The total amount of contaminants contributed from this process is
quite small.  The equipment used has stood the tests of time.  Of
course   there  will  always  be  occasional  leaks  and  spills.
Whether a plant recycles or discharges to a sewer determines  the
concentration  of  contaminants and water usage.  When recycle is
practiced, as little as 10.4 1/kkg (1.25 gal./1000 Ib)   of  water
is  used.   Concentrations  in this case were high - 6000 mg/1 of
BOD5 and 21,000 mg/1 of COD.  The other extreme was 4170 1   (1100
galT)  of water - a BODj> of 85 mg/1 and a COD of 245 mg/1.

Because of the variety of products made we observed quite a range
of  waste  loadings:   BODS  -  0.07  kg  -0.8 kg/kkg  (0.07 Ib -
0.81b/1000 Ib) of product,~COD - 0.2 kg - 2.3 kg (0.2  Ib  -  2.3
Ib) ,. MBAS - 0.1 kg - 3.1 kg (0.1 Ib - 3.1 Ib) .

SPEAY DRIED DETERGENTS —(PROCESS 207)

introduction

This  is probably the single largest volume unit process utilized
by the soap and detergent industry.  There is great variation  in
the  operation  of spray towers insofar as water use and reuse is
concerned.  These variations  result  from  different  processing
characteristics  of  product  formulas, influences of air quality
problems, standards and frequency  of  product  changeovers,  and
plant integration.

The  principal  sources of contaminated water are washdown of the
tower - 207312; scrubber waters - 207301 and  207330;  and  leaks
and spills - 207202 and 207302.

Water and Waste Water Balance

No  cooling  water  is  used  in this process.  All process water
which is added to the crutcher leaves the process as water  vapor
from  the spray tower (207308),  Therefore, all water used is for
various types of cleanup.  Some plants employ  total  recycle  of
cleanup  water  and  therefore have a very low rate of discharge.
Some plants discharge all waste waters to  the  municipal  sewer.
Most  plants  are  intermediate  and  specific  problems  must be
recognized to be able to understand water disposal practices.

To be able to maintain desirable air quality it may be  necessary
to use very large quantities of water for scrubbing organics from
spray  tower  vent  gases.   This  problem  is still under study.
Frequent  product  changeovers  for  smaller   plants   make   it
economically and physically impossible to collect and recycle all

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tower washouts.  Highly integrated plants have more opportunities
to recycle or use detergent-laden waste waters.

Typical  water  usage  associated  with  spray  tower  operations
include:  wet scrubbing of air  emissions,  30-200  gal/1000  Ib;
equipment washouts  (crutchers, spray towers, packaging, etc.), 5-
55  gal/1000  Ib; and clean-up of leaks and spills, 2-20 gal/1000
Ib.  Total waste water discharges encountered  ranged  from  less
than 5 gal/1000 Ib to as much as 250 gal/100 Ib.

Waste Water Constituents

All  of the streams will be contaminated with the detergent being
produced in the plant at  the  time.   The  various  surfactants,
builders  and  additives  are listed on the flow diagram entering
2071 Receiving Storage And Transfer.

These constituents will contribute to BODj>, COD, MBAS,  dissolved'
and suspended solids, oil and grease and alkalinity.

Average raw waste loads for the three types of operation of spray
towers  are  tabulated as follows (kg/kkg dry detergent) (lb/1000
Ib) :

                   BOD5   COD    Suspended               Oil and
                                   Solids  Surfactants   Grease

Few turnarounds &
no air quality
problem            0.1    0.3      0.1        0.2          nil

Air quality
problems           0.8    2.5      1.0        1.5          0.3

Fast turn-
around             0.2    0.4      0.2        0.4          0.03

LIQUID DETERGEtjT MANUFACTURE__-- (PROCESS 208)

Introduction

Manufacture of liquid light-duty hand dishwashing and  heavy-duty
laundry  detergents  requires  relatively  simple  equipment  for
blending the various ingredients.  Usually this is done batchwise
with the several surfactants being  added  by  weight,  and  then
thoroughly blended.

Filling  of  the  bottles  is  done  on  sophisticated high speed
filling lines.  This is a most critical and  difficult  operation
because of machine complexity, speed, and cost.

From the filling line, leaks, spills and overflows are sources of
water contamination (208302).  From both the blending and filling
operations,  purging  the lines between products produce slugs of
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detergent, contaminated water (208212, 208213 and 208302).   Also,
filled detergent bottles are sometimes washed (208310).

Contaminants  from  light-duty liquid detergents are very high in
surface active agents.  Heavy-duty liquid detergents, produced in
much lower volume, can result in some contamination with builders
(phosphates, carbonates).

Water and Waste Water Balance

Liquid detergents consume water as  the  major  solvent  for  the
product.  Little or no water is used for heating and cooling, but
large  amounts  of  water  are  used  for  washing  equipment and
packages.  Because very small amounts of  liquid  detergents  can
cause  extraordinary amounts of foam, it is necessary to use very
large volumes of water; and recycle or  reuse  of  water  becomes
impracticable.  Reported water usage was in the range of 625-6250
1/kkg  (75-750 gal/1000 Ib)  of detergent.

Waste Water Constituents

All of the effluent streams will contain the starting ingredients
of the products.  These are mainly:


ammonium, potassium S sodium  alkylbenzene sulfonates  (LAS)

ammonium, potassium & sodium  alcohol ethoxy sulfates  (ASS)

ammonium, potassium & sodium  alkylphenol ethoxy sulfates

ammonium, potassium & sodium  olefin sulfonates        (OS)

ammonium, potassium & sodium  toluene and xylene sulfonates
                               (hydrotropes)

ammonium, potassium & sodium  alcohol sulfates

Fatty acid alkanol amine condensates (amides)

Urea .(hydrotrope)

Ethanol  (hydrotrope)

Polyacrylates and polystyrene  (opacifiers)

Dyes & perfume

Phosphate & citrate builders

Silicate builders

These  constituents  will  contribute  to  alkalinity, BOD5, COD,
nitrogen, MBAS  (and undetected surfactants) and dissolved  solids.
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Raw waste loadings vary more in concentration than  total  amount
between plants.  The following were observed:

          kg/kkq of detergent        rnq/1

BOD5             0.5-1.8             65 - 3UOO

COD              1.0 - 3.1             120 - 7000

MBAS             0.4 - 1.1             60 - 2000

As  much  as 90 percent of the detergent can come from washout of
tanks and lines when changing products.  With fewer changes waste
loads will decrease, but the lower  levels  in  the  above  table
represent minimum with current practice.

DETERGENT MANUFACTURING BY DRY BLENDING — (PROCESS 209)

Introduction

Production  of  detergents  by this process requires no water for
processing and can be operated without using water for  washdown.
Dry   builders  and  surfactants  are  simply  mixed,  or  liquid
surfactants are sprayed into dry powders so that the entire  mass
stays  free flowing.  Some water may also be sprayed onto the dry
powders to produce more stable hydrates.

DRUM DRIED DETERGENTS — (PROCESS 210)

Introduction

In this detergent drying process, the aqueous slurry of detergent
is dried on steam heated rolls and recovered as  flakes.   Little
or no formulated household detergent is now made by this process.
Most  of  the  products  are  high  active  LAS  products for dry
blending of industrial detergent products.

Water and Waste Water Balance

The detergent slurry contains water added in  the  neutralization
process  No.  206.   This water is removed as steam and vented to
the  atmosphere  or  scrubbed  (201201).   Steam  condensate   is
generated   also,  but  this  should  be  free  of  contamination
(210203).

Waste Water Constituents

The only appreciable effluent will be similar to,  but  lower  in
concentration than the scrubber water from spray drying (207301) .
Surfactants, builders, and free oils can be expected.  These will
contribute  to  BOD.5, COD,  alkalinity,  MBAS,  dissolved solids and
oil and grease.

DETERGENT BARS AND CAKES — (PROCESS 211)
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This process is similar in operation to Process  106  Bar  soaps.
The  significant  difference arises in the more frequent washouts
required because of the heat sensitivity of the detergent  active
ingredient.  Wash waters will be similar in character to those of
spray dried detergents.

In  some  instances  soap  will  also be found in the waste water
since it is a part of the blend comprising some toilet bar soaps.
                                  78

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                           SECTION VI

                      POLLUTANT PARAMETERS
This section contains a discussion of the  specific  contaminants
which  were  selected  for  guidelines recommendations, and those
which were omitted.  Rationales for the decisions are  given  for
each pollution parameter.


Production  of  soaps  and  detergents  results in numerous waste
water streams and several types  of  contaminants  which  are  of
special concern.  Synthetic surface active agents not only create
a  BOD5  and  COD,  but  also  cause  water  to  foam and in high
concentrations  can  be  toxic  to  fish  and  other   organisms.
Nutrients,  particularly  phosphate,  are  of  concern because of
their contribution to eutrophication of lakes.   Soap  production
leads  to  waste waters with high alkalinity, high salt, and high
oxygen demand.  Spills of raw materials  contribute  to  oil  and
grease  levels.  Most of the suspended solids come from organics;
i.e., calcium soaps, and many are of  the  volatile  rather  than
non-volatile  type.   Since  strong acids and strong alkalies are
used, pH can be very high or very low in waste waters.

CONTROL PARAMETER RECOMMENDATIONS

To monitor the quality of the treated waste  water  flows  coming
from  soap  and  detergent plants as point source discharges, the
key  parameters  recommended  for  sampling  and   analysis   and
structure of guidelines are:


Biochemical Oxygen Demand

All  of  the organic active materials found in soap and detergent
formulations are biodegradable  in  varying  degrees.   Most  are
totally  and  rapidly  assimilated, and thus may adversely affect
the  oxygen  balance  of  receiving  waters.    Although   highly
criticized for its lack of reliability, the analytical method for
BOD5  is  still  the  only  generally accepted method for grossly
measuring   the   potential   impact    on    the    environment.
Unfortunately,  not  all  of the organic materials found in these
waste water flows contribute to the oxygen  demand  at  the  same
rate.   Some  may  inhibit the microorganisms which degrade these
contaminants, and others are incorporated into the cell tissue of
the microorganisms at different rates.  This leads to varying ra-
tios of BOD5 values when compared to the companion COD test.

There are a number of factors which tend to reduce reliability of
the BOD5 in actual  practice.   One  difficulty  stems  from  the
frequent  need  for  long  term  acclimation  of the biota to the
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special  unique  organic  substrates  encountered  in  the  waste
streams  from the manufacture of detergents.   Too often biota are
employed in the BOD5 tests which are totally unacclimated, or  at
best  only  partially  acclimated.   When  data derived from such
testing are viewed in isolation they  tend  to  indicate  that  a
large  quantity  of such organics are resistant to biodegradation
or are only slowly degraded.  However, detailed  studies  carried
out  with  thoroughly acclimated microbial systems do not support
this casual observation.  In fact, the vast bulk of the materials
now employed as synthetic detergents are  subject  to  rapid  and
complete  assimilation  by acclimated saprophytic microorganisms.
Industrial  surfactants  production  does  lead   to   a   higher
refractory component than the household surfactants.

The  use  of  the  BOD5  test is recommended.  However, it is es-*
sential that acclimated biota be maintained,  especially where the
concerned effluent originates from a plant  producing  industrial
cleaners.

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 production of noxious gases
such as hydrogen sulfide and methane.   Water  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
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algae blooms due to the uptake of degraded  materials  that  form
the foodstuffs of the algal populations.

Chemical Oxygen Demand

Chemical  oxygen  demand   (COD)  is  another  measure  of  oxygen
consuming pollutants in water.  COD differs from BOD, however, in
that COD is a measure of the total oxidizable carbon in the waste
and relates to the chemically-bound  sources  of  oxygen  in  the
water  (i.e.,  nitrate  which  is chemically expressed as NO3.) as
opposed to the dissolved oxygen.  Materials exerting COD are  not
readily  biodegraded   (as  is  the  case,  for  example, with the
complex chemicals, i.e., long chain fatty acids,  from  soap  and
detergent  manufacturing)  and  as  a result chemical balances in
streams are altered.  Since COD is usually encountered coincident
with BOD, the combined effect is highly deleterious.  Because  of
the  difficulty discussed in the preceding section concerning the
reliability of BOD5, it is recommended that the COD be used as  a
primary   parameter   for   characterizing  effluents  from  this
industry.  Special attention must be given to insure the complete
oxidation of these materials.
Total Suspended JSolids

Although the waste  water  sources  of  the  soap  and  detergent
industry  are  not  notably  heavy in suspended solids, suspended
solids should be monitored to insure that stream clarity  is  not
unduly  affected  or  sludge  deposits  formed on the stream bed,
particularly by some upset in the processing train.

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


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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 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.


Surfactants (MBAS)

Because  of their possible contribution to foaming in streams and
biological upset through surface effects or toxicity, measurement
and control of the organic  active  ingredient  in  effluents  is
necessary.   Not all organic active materials are measured by the
MBAS procedure,  soaps are  not  detected,  nor  are  non-ionics.
However,  both  of  the  latter  are measured by the EOD5 and COD
methods.

Oil and Grease

These materials which contribute to visual and olfactory esthetic
problems, exert oxygen demand, and interfere with  normal  oxygen
transfer from air to water need to be controlled.  The analytical
method  picks  up  not only the fatty oils and grease used in the
soap  making  process,  but  any  hydrocarbon  bodies  which  are
generated  from  the  synthetic  detergent  portion  of the plant
processes.  The test method does not distinguish between the  two
sources,   therefore,   the  results  must  be  interpreted  with
discretion.


Oil and grease exhibit  an  oxygen  demand.   Oil  emulsions  may
adhere  to  the  gills of fish or coat and destroy algae or other

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plankton.  Deposition of oil in the bottom sediments can serve to
exhibit normal benthic growths,  thus  interrupting  the  aquatic
food chain.  Soluble and emulsified material ingested by fish may
taint the flavor of the fish flesh.  Water soluble components may
exert  toxic  action  on  fish.   Floating oil may reduce the re-
aeration of the water surface and.in conjunction with  emulsified
oil   may   interfere   with   photosynthesis.   Water  insoluble
components damage the plumage and  costs  of  water  animals  and
fowls.   Oil and grease in a water can result in the formation of
objectionable  surface  slicks  preventing  the  full   aesthetic
enjoyment of the water.

Oil  spills  can  damage the surface of boats and can destroy the
aesthetic characteristics of beaches and shorelines.

pH, Acidity and Alkalinity

This is a pollutant characteristic important  for  control  since
there  are  occasional  upsets in those portions of the processes
which could potentially lead to highly acidic or alkaline  spills
and upset the normal regimen of the receiving waters.


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


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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.

Parameters Omitted

Among the parameters omitted is dissolved  solids.   While  there
will  be  times  of  high  concentrations of salts in some of the
waste water  flows  within  the  plant,  by  the  time  they  are
commingled  with  the  total  plant  effluent  they will be quite
dilute.  In addition, the salts themselves are not in a  toxicity
range  of  concern.   If  the  contamination  of  the  waters  by
dissolved solids could be damaging, the permit granting authority
should then issue specific guidelines  covering  that  particular
situation.

Nitrogen

Nitrogen,  although important in the general concern in regard to
the quality of the receiving waters, is omitted since there is at
this time very little use  of  products  derived  from  nitrogen.
Spot  checks of industrial effluents and contractor's analysis of
Corps   of   Engineers   permit   applications   confirmed   this
observation.

Phosphorus and,Boron

Phosphate  and  boron  levels found in the raw wastes and treated
effluents from plants  manufacturing  soaps  and  detergents  are
comparable to those encountered in the influents and effluents of
well  operated municipal treatment plants.  Moreover, measures to
control  the  selected  parameters   will   effectively   control
phosphate  and  boron levels.  While the importance of phosphorus
as a nutrient  (and a potential cause on nuisance aquatic growths)
is well recognized, it is questionable that complete  elimination
of  all  phosphates from point source discharges in this industry
would have a detectable affect on phosphorus levels  in  any  but
the most exceptional receiving waters.


During the past 30 years, a  formidable case has developed for the
belief  that  increasing standing crops of aquatic plant growths,
which often interfere with water uses and are nuisances  to  man,
frequently are caused by increasing supplies of phosphorus.  Such
phenomena   are    associated with  a  condition  of  accelerated
eutrophication or  aging of waters.  It  is  generally  recognized
that   phosphorus   is  not   the  sole cause of eutrophication, but
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there is evidence to substantiate that it is frequently  the  key
element in all of the elements required by fresh water plants and
is  generally  present  in  the  least  amount  relative to need.
Therefore, an increase in phosphorus allows use of other, already
present, nutrients for  plant  growths.   Phosphorus  is  usually
described, for this reasons, as a "limiting factor."

When a plant population is stimulated in production and attains a
nuisance  status,  a  large  number of associated liabilities are
immediately apparent.   Dense  populations  of  pond  weeds  make
swimming  dangerous.   Boating  and  water  skiing  and sometimes
fishing may be eliminated because of the mass of vegetation  that
serves  as  an  physical  impediment  to  such activities.  Plant
populations have been associated with  stunted  fish  populations
and  with  poor  fishing.   Plant  nuisances  emit vile stenches,
impart tastes and odors to water supplies, reduce the  efficiency
of  industrial  and  municipal  water treatment, impair aesthetic
beauty,  reduce  or  restrict  resort  trade,  lower   waterfront
property  values,  cause skin rashes to man during water contact,
and serve as a desired substrate and breeding ground for flies.

Phosphorus in the  elemental  form  is  particularly  toxic,  and
subject  to  bioaccumulation  in  much  the  same way as mercury.
Colloidal elemental phosphorus will poison marine  fish   (causing
skin  tissue  breakdown  and discoloration).  Also, phosphorus is
capable of being concentrated and will accumulate in  organs  and
soft  tissues.   Experiments  have  shown  that  marine fish will
concentrate phosphorus from water containing as little as 1 ug/1.

Scope of Parameter Measurements - By Processes

Each of the  individual  processes  of  the  soap  and  detergent
industry  are  reviewed  in  the following paragraphs in order to
relate the significance of the parameters chosen  for  guidelines
to  the  measurement of the contaminants contained in waste water
flows originating in each unit process.

The ways  in  which  effluent  discharge  can  be  monitored  are
suggested.
SOAP MANUFACTURE BY BATCH KETTLE  M 01)
          '  '  r T ~~ x           -   \  "

Significant  contaminants from this process are the fats and oils
used as raw material; unrecovered sodium chloride, sodium sulfate
and sodium hydroxide; soaps that are spilled  or  lost  and  dark
colored  by-product soaps.  Limits are proposed for BODf> and COD,
suspended solids, oil and grease and a range of 6  -  9  for  pH.
The  soaps,  fats  and  oils will be controlled by the first four
                            85

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tests.  A pH in the 6-9 range will insure against discharge  of
sodium hydroxide or strong acids.

Since  soap plant wastes can cause depletion of dissolved oxygen,
limitation is necessary. Oils and suspended solids cause esthetic
problems.  A very high or very low pH is  detrimental  to  almost
all organisms.

No  recommendation  has been made for specific limitations of the
two inorganic salts, NaCl and Na.2SO.jl.  These are relatively  non-
toxic  (Nad  10,000-20,000  mg/1  MLD;Na SO.  11,000-17,600 mg/1
MLD) , and most receiving waters are below the limits of dissolved
salts set by the United States Public Health Service.

FATTY ACIDS BY FAT SPLITTING  (102)

The organic compounds from this process are primarily fatty acids
although some unreacted fat and glycerine from spills  and  leaks
will  also  be  found.   The  total of the inorganics will be low
compared to the organics.  Sodium hydroxide  and  sodium  sulfate
from  fat  pretreatment  and  from treatment of still bottoms are
expected.

Total organics should be  controlled  by  setting  BOD5  and  COD
limits.   Free  fatty  acids  and  fats  should  be controlled by
setting oil and grease  and  suspended  solids  limits.   The  pH
should be controlled.

Contaminants  not  limited  are  the  generally  innocuous sodium
sulfate plus small amounts of zinc and alkaline earth metals used
as the fat splitting catalyst and nickel used as a  hydrogenation
catalyst.   These  metals ions are below harmful concentration in
commingled plant wastes and are  further  reduced  in  biological
treatment   processes   which   must   be  used  on  the  organic
contaminants.

SOAP BY FATTY ACID NEUTRALIZATION  (103)

Except for fats and oils the contaminants from this process  will
be the same as from the kettle boil soap process.  Concentrations
and loadings are much lower, however.

Control  of  discharge  is established by setting limits on BOD5,
COD, pH, suspended solids and oil and grease.

The small amount of sodium chloride relative to the production of
soap should not require regulation unless the receiving stream is
at a critical chloride  level.

GLYCERINE RECOVERY  (101\

Contaminants in waste waters  from this process are water  soluble
organics and two inorganic salts.  The organics are glycerine and
glycerine polymers.  The salts are NaCl and
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Organics  discharge is controlled by setting BODfj and COD limits.
Although pollutants affecting pH, suspended solids, and  oil  and
grease  are  minimal, limits have been set to guard against carry
over from previous processing steps.

Sodium chloride and  sodium  sulfate  should  not  be  restricted
unless  the  receiving stream is close to the specified limit for
chloride and sulfate ions.

SOAP FLAKES AND POWDERS  (105)

Effluents from this process are minimal.  Since almost pure  soap
is  processed,  the contaminants will be primarily soap with only
small amounts of free fatty matter, alkali and salt.

BOD5 and COD are used to limit discharge of soaps, and pH  is  to
be  kept to the 6-9 range.  Suspended solids and oil and grease
should be measured to guard against unusual contamination.

Although sodium chloride is not limited, its concentration should
be negligible.

BAR SOAPS  (106)

As with soap flakes and powders, waste  water  contaminants  from
this  process  will  be  mainly  soap.  Small amounts of salt and
alkali which are in the soap will also be found.  Some free fatty
matter and additives can be expected in the waste waters.

Assignment of BOD5 and COD limits will control the  discharge  of
soap.   Specifying  limits  for pH, oil and grease, and suspended
solids will handle unusual spills.

Inorganic contaminants  should  be  low  and  control  should  be
unnecessary.

LIQUID SOAP (107)

Liquid  soaps  are formulated products and will contain solvents,
builders, dyes and  perfumes  in  addition  to  potassium  soaps.
Almost all contamination will come from spills so the waste water
will be contaminated with all constituents of the formula.

BODS  and  COD limits will control overall discharge of organics.
Control of pH to the 6.0 - 9.0 level should  present  no  problem
since  the  product  will be in that range.  The suspended solids
and oil and grease tests will be more important  here  than  with
other  soaps since the formulated soaps often contain hydrocarbon
solvents.

Inorganic salts should be negligible from this process  and  thus
require  no  control.   Potassium  ion will be found here but the
level should be low enough to require no limitations.
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OLEUM SULFONATION AND SITUATION (201]|

In effluents from this process, one can expect to find  the  oily
raw  materials, sulfuric acid and surfactant sulfonic acids.  All
of these contaminants need to be treated before discharge.

Raw material spills should be limited by  setting  specifications
for  the  oil and grease and suspended solids.  The MBAS test can
measure surface active sulfuric acid esters and be used to  limit
their   concentration.    Total   organic  contamination  can  be
monitored and controlled by running the oxygen demand procedures,
BOD5 and COD.  Sulfuric acid and sulfonic acids are  very  strong
acids  and  must  be  neutralized  before discharge.  This can be
assured by specifying a pH of 6 - 9.

The only contaminant not limited is sulfate.   Most  streams  can
absorb  current  quantities  of  this  ion,  but if necessary the
regional permit officer can restrict discharge of sulfate.

AIR SO3 SULFATION - SULFONATION (202][

This process is identical to process 201  with  respect  to  con-
taminant  composition.   However, the levels of contamination are
higher.

Limitations have been set for BOD5, COD, pH. oil and grease, MBAS
and suspended solids.  Sulfate need not be limited for the  usual
receiving water.

see the discussion under Process 201 for the rationale.

VACUUM AND SOLVENT SULFONATION  (203)

This process is identical to process 201 insofar as contamination
is  concerned.  One exception is the possible presence of sulfate
in the waste water.  Levels should be similar to process 201.

Limits have been set for BODfi, COD, pH, oil and grease  and  sus-
pended solids.  Sulfate should generally be exempted.

For rationale see Section 201.

SULFAMIC ACID SULFATION  (204)

This  reaction  is  rather  limited in scope, but can have a high
discharge because of washdown  after  each  batch.   Contaminants
will  be  unsulfated  ethoxy alcohols, sulfamic acid and ammonium
ether sulfates.

The MBAS test and a limitation  for  the  process  will  be  most
useful  for  control.   Because  the  MBAS  test does not pick up
nonionic surfactants. BODjj and COD  are  needed  to  control  the
overall  organic load.  As usual, pH control will be needed since
sulfamic acid is a strong acid.


                             88

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Sulfamic acid hydrolyzes to ammonium acid  sulfate  in  water  so
that  no control is needed unless the receiving water is close to
its limit for nitrogen and sulfate.

The organic contaminants from this  process  will  be  feedstock,
fatty alcohols, alcohol ethoxylates and alkyl phenol ethoxylates.
Also,  the  sulfated  products and the final ammonium, sodium and
triethanol amine salts will be found.  Inorganics will be  hydro-
chloric and sulfuric acids plus ammonium and sodium ions.

Limitations   have   been   established  for  total  organics  by
specifying BOD5 and COD  values.  MBAS  should  be  measured  and
controlled.   Raw material spills can be controlled by specifying
suitable values for oil and  grease  and  suspended  solids.   As
usual, pH needs adjustment to the 6.0 - 9.0 level.

NEUTRALIZATION OF SULFURIC ACID ESTERS AND SULFQNIC ACIDS  (206}

In  this  process  the  organic  acids  produced by sulfation and
sulfonation are reacted with bases to produce the desired  salts.
Therefore, contaminants will be the products of processes  201,202
and  203.   In addition, the neutralized products and the  various
cations will be present.

The MBAS test, and a limitation thereon,  will  be  important  in
controlling  contamination  from  this  process.   BOD5  and  COD
allowances will  determine  overall  organic  contamination.   To
assure  a  neutral  waste water, pH adjustment will be necessary.
Oil and  grease  and  suspended  solids  should  be  minimal  but
specifications are needed for unusual spills.

Control of inorganic sulfate, potassium, sodium and ammonium ions
is believed unnecessary for most receiving streams.

SPRAY DRIED DETERGENTS J207)

Effluents  from  this  process  will  contain  all  of  the  many
ingredients used in dry detergent powders:  LAS, amide,  nonionic
and alcohol surfactants: sodium phosphate, carbonate and silicate
builders;  carboxmethyl  cellulose, brighteners, perborate, dyes,
fillers and perfumes.

An MBAS limit will handle anionic surfactants, but COD  and  BOD5
tests   are   needed  to  estimate  other  surfactants.    Careful
attention needs to be paid to BOD5/COD ratio  since  the   various
surfactants  can  inhibit  or react slowly with unacclimated BOD5.
cultures.                                                       ~

The suspended solids test will serve to limit insolubles and  the
oil  and  grease limit is needed for spill of oils from the spray
tower.

Specific  limits  have  not  been  recommended   for   carbonate,
silicate,  phosphate  and  sodium  ions.   The  condition  of the


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receiving stream should  be  determined  by  the  permit  officer
before limiting these contaminants.


LIQUID DETERGENTS (208)

These  products  are  made  by  simple blending so effluents will
contain the starting ingredients.  High levels of organic surface
active agents can be expected from washdown and cleanup.   Heavy-
duty  liquid  detergents  will  also contain potassium phosphate,
silicate   and   citrate   builders   and   solvents    (ethanol).
Hydrotropes  (sodium  xylene  sulfonate  and  urea)   will also be
found.

To control total organics the  BODjj  and  COD  levels  have  been
specified.   MBAS  limits  have been set to control the important
anionic surfactants.  Limits on pH, oil and grease, and suspended
solids have been set but control measures should be unnecessary.

Except for the generally innocuous inorganic  salts,  levels  for
all contaminants have been specified.

DRY DETERGENT BLENDING  (209)

This  process  usually  has  a  very  low  effluent  level.   Any
contaminants will be the same as those discussed in Section 207  -
spray dried detergents.  Our rationale for  limiting  BOD5,  COD,
pH, suspended solids, MBAS and oil and grease are the same also.

DRUM DRIED DETERGENTS  (210)

Almost  exclusively  devoted  to  the  manufacture  of industrial
detergent powders, this  process  uses  a  wide  variety  of  raw
materials.   They  find  their way into waste water flows through
spills and washouts.  BOD5, COD and surfactant  (MBAS) limits will
govern these sources, coupled with pH.

There should be no oil and grease appearing in  any  waste  water
from this process.

DETERGENT BARS AND CAKES  (211)

Processing  of detergent bars is almost identical with  soap bars.
However,  the  wastes   will   contain   synthetic   surfactants.
Therefore,  in  addition  to  setting  limits  on  BOD5, COD, pH,
suspended solids and oil and grease, it is necessary to specify  a
limit on MBAS.

The rationale for the limits and parameters will be  found  under
process 106.

Industrial Cleaners
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Industrial  cleaning compounds are also manufactured in plants of
the soap and detergent industry.  Insufficient data was  obtained
to  make  specific  recommendations on the multitude of compounds
employed but some guidance can  be  given.   Industrial  cleaners
make  up about 10 percent of the industry output.  The studies of
the Organic and Inorganic Chemicals Industries  are  expected  to
provide  much  useful  treatment  data on some of the more exotic
chemicals.  The phosphates,  silicates,  carbonates  and  caustic
alkalis  which are employed will create the same basic situations
as  are  discussed  in  processes  207,  208  and  209.   Similar
treatment procedures and guidelines also apply.

Other  material not sufficiently characterized but which might be
expected in the industrial waste waters  are  hydrogen  fluoride,
sulfamic  acid,  phenols  and  cresol,  chlorinated hydrocarbons,
complex organic and inorganic corrosion  inhibitors,  and  exotic
surfactants.   Fluorides  can  be  easily precipitated with lime.
Sulfamic  acid  and   cresol   are   readily   biodegradable   if
concentrations  are  kept  low.  The chlorinated hydrocarbons may
have to be removed by solvent extraction  or  carbon  absorption.
Some  corrosion  inhibitors used in acids for industrial cleaning
are complex organics which will require  individual  study.   The
exotic  surfactants  will include phosphoro-, fluoro- and silico-'
organo compounds  which  have  unknown  treatat>ility.   Nonionic,
amphoteric,   and   low  molecular  weight  wetting  agents  with
different treatability can also be expected.  The limits on BOD{>,
COD, suspended solids, surfactants, oil and grease and pH  should
effectively  control  industrial  cleaners  in  the subcategories
involved in their production, but the area of industrial cleaners
merits additional study.
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                           SECTION VII

                CONTROL AND TREATMENT TECHNOLOGY

Introduction

The  key  to great reductions in the pollution load from the soap
and detergent industry  is  lower  process  water  usage.   Those
processes  using  the most process water per unit mass of product
made are also the greatest contributors of pollutants.

One of the biggest improvements  would  be  either  changing  the
operating techniques associated with the barometric condensers or
replacing   them  entirely  with  surface  condensers.   Complete
replacement would reduce many fold  the  use  of  water  in  most
processes  and at the same time cut down greatly on the amount of
organics now being sent to sewer.  These organics normally have a
market value (when further purified)  which may provide a positive
payout on the improvement introduced.

Barometric condenser  operation  could  be  greatly  improved  by
recycling  the  water  through  a  fat  skimming operation (where
marketable fats and oils could be  recovered)   and  then  through
cooling  towers.   The  only  waste  would  be a continuous small
blowdown from  the  skimmer  to  keep  soluble  materials  within
acceptable   limits.    Fat   splitting   operations  which  have
barometric condensers equipped with  such  cooling  and  skimming
equipment   already   meet   the   recommended   guidelines  with
considerable ease.

Another area where a large reduction  in  water  usage  could  be
effected is in the manufacture of liquid detergents.  This can be
attained  by  installation of additional water recycle piping and
tankage and by the use of air  rather  than  water  to  blow  out
filling lines.   This latter change will also minimize the loss of
finished product.

One  of  the  large  integrated  plants  making  both  soaps  and
detergents has  achieved  almost  zero  discharge  of  pollutants
through  a  painstaking, ten-year effort.  One of the first tasks
which had to be undertaken, and still the  biggest  obstacle  for
most fairly old integrated plants, was identifying and untangling
the  waste  water  lines which now lead to the sewer.  Only after
such identification, monitoring and study could the effluents  be
managed better.

With  few  exceptions,  the contaminants in waste waters from the
soap and detergent  industry  are  really  saleable  products  in
disguise, especially those relating to distillation equipment and
entrainment  separators.  Wherever a distillation is carried out,
whether  on  a  batch  basis  or  by  multi-component  continuous
fractionation,   there  is  an entrainment of liquid droplets from
one tray of a tower to the tray  above.   This  is  essential  in
order  to accomplish good vapor-liquid contacting and to make the
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efficiency of the  physical  transfer  of  the  highest  possible
order.  However, it does result in carrying droplets of liquid by
the  vapor  from  the stage below to the stage above.  The use of
one or two additional special trays  in  a  distillation  column,
whether used in concentration as in glycerine manufacture or used
for  the  separation  of components as in fatty acid manufacture,
will not only eliminate carryover in the form of entrainment  but
will  lead  to  a more complete separation and a higher purity of
each component of a multi-component distillation feed.

NATURE OF POLLUTANTS

The soap and detergent industry produces  wastewaters  containing
both  conservative  and  nonconservative pollutants which must be
treated, removed from the waste stream, and  ultimately  disposed
of  under  controlled  conditions.  The important nonconservative
pollutants consist of organic raw materials, fats  and  oils  and
lost   portions   of  finished  product,  soap  and/or  synthetic
detergent.  Mineral solids, catalysts and builder materials  such
as  borate and phosphate also appear in the effluents in moderate
concentrations.  Some of these substances reach polluting concen-
trations in plant effluents which then have to be  treated.   The
pollutants  of  primary  concern, together with the concentration
ranges within which they are generally found in plant  raw  waste
effluents are as follows:

1.   Oils and greases (0-3400 mg/1)
2.   Suspended organic material other than oils and
     greases  (0-30,000 mg/1)
3.   Dissolved or finely dispersed colloidal organic
     substances which contribute to the chemical and
     biochemical oxygen demands.   (100-12,000 mg/1)
4.   Certain organics with surfactant properties.
      (0-1700 mg/1)

In  addition  to  pollutants per se, the alkalinity or acidity of
wastes is also a primary concern and may mandate the treating  of
a plant effluent.

Of secondary concern in raw wastes are the following pollutants:

1.   Boron or borates (less than 1 mg/1)
2.   Phosphates  (25-1000 mg/1)
3.   Dissolved mineral solids (0-250,000 mg/1)
4.   Zinc and barium (less than 1 mg/1)

It should be noted that the higher values in the ranges listed
above are representative of small individual waste streams and would not
be representative of the total raw effluent for a plant or even a subcategory.

Since  phosphate compounds are used in the manufacture of several
types of detergent, some of them inevitably find their  way  into
the  process waste streams.  The concentrations actually measured
vary widely and the data are not sufficiently  complete  to  make

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absolute  judgments  concerning  typical  levels  for many of the
operations  carried  out  in   the   industry.    However,   some
generalizations can be made.


    In   the   closely   controlled,  well  operated,  integrated
manufacturing facilities examined as a part of the present study,
where phosphoric acid type cleaners were not being produced,  the
concentrations  of phosphorus contained in the combined raw waste
was generally  under  25  mg/1  as  phosphorus.   In  those  same
facilities the average concentrations were typically 5-10 mg/1 as
phosphorus;  i.e.,  of the same order as is contained in domestic
sewage.

Table 2 indicates the treatment technology which can  be  applied
to   the  appropriate  waste  streams  for  removal  of  specific
pollutants of concern.

More specific  consideration  of  the  best  practicable  control
technology  currently available and the best available technology
economically achievable is contained in Sections VIII, IX and X.
DISCUSSION OF TREATMENT TECHNIQUES

The treatment technologies discussed are standard and in  routine
use.   Operating  and  design techniques are well established and
have  been  reported  upon   extensively   in   the   literature.
Therefore,  only  a  brief  discussion  of  such  operations  and
processes is included in  this  report.   A  list  of  the  major
pollutants  and treatment methods usually employed to handle them
are given in Table 2.  Removal efficiencies  for  some  of  these
treatment methods are given in Table 3.

Oil  and	Grease	Removal  -  This may be accomplished by the ap-
plication of any one, or a combination of three basic  separation
methods - gravity separation, physical filtration, or adsorption.
The  gravity  separators  are designed to handle loads of 20,500-
41,000 1/day/sq m (500-1,000 gpd/sq ft) of surface.  The  filters
are normally operated at 205-615 1 /min/sq m (5-15 gpm/sq ft).

Carbon  and  other  related  solid  phase  adsorption  operations
require approximately 0.15-0.68 kg (1.0-1.5 Ib) of adsorbent  per
O.U5  kg (1 Ib)  of oil removed.  Flotation operates very much the
same  as  the  sedimentation  operation  in  terms  of   over-all
efficiency.   Air rates are usually maintained around O.OOU-0.011
cu m/min/cu m (C.5-1.5  cu  ft/min/100  gal)   of  recycled  flow.
Chemical doses of FeC13, alum, or lime vary from 50-150 mg/1.
                              95

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                             TABLE 2
       Treatment Methods Used in Elimination of Pollutants
Pollutants

Free and emulsified
oils and greases
Suspended Solids
Dispersed Organics
Dissolved Solids
(Inorganic)
Unacceptable Acidity
or Alkalinity

Sludge obtained from
or produced in
process
Treatments

1.  Gravity separation
2.  Coagulation and sedimentation
3.  Carbon adsorption
U.  Mixed media filtration
5.  Flotation

1.  Plain sedimentation
2.  Coagulation-sedimentation
3.  Mixed media filtration

1.  Bioconversion
2.  Carbon adsorption

1.  Reverse osmosis
2.  Ion exchange
3.  Sedimentation
U.  Evaporation
1.  Neutralization

1.  Digestion
2.  Incineration
3.  Lagooning
4.  Thickening
5.  Centrifuging
6.  Wet oxidation
7.  Vacuum filtration
                               96

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                             Table 3

Relative Efficiency of Several Methods Used in Removing Pollutants

Pollutant and, Method            Efficiency  (Percentage of Pollutant Removed]_
Oil and Grease
API type separation
Up to 90 percent of free oils and greases.
Variable on emulsified oil.
Carbon adsorption
Up to 95 percent of both free and
emulsified oils.
Flotation
Without the addition of solid
phase, alum or iron, 70-80 percent of
both free and emulsified oil.
With the addition of chemicals,
90 percent
Mixed media filtration
Up to 95 percent of free oils.
ciency in removing emulsified
oils unknown.
 Effi-
Coagulation-sedimentation
with iron, alum or solid
phase  (bentonite, etc.)

Suspended Solids

Mixed media filtration

Coagulation-sedimentation
Up to 95 percent of free oil.
90 percent of emulsified oil.
70-80 percent

50-80 percent
Up to
Chemical Oxygen Demand

Bioconversions (with final
clarifier)
60-95 percent or more

Up to 90 percent
Carbon adsorption

Residual Suspended Solids

Sand or mixed media filtration  50-95 percent

Dissolved Solids

Ion exchange or reverse osmosis Up to 99 percent
                                97

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Coagulation  and  Sedimentation  -  These  units  are designed to
provide between 30 and 60 minutes of  coagulation  time  and  are
normally  designed  for  surface  loading  rates of 16,400-61,500
I/day sq m (400-<1500 gpd/sq ft) depending upon the nature of  the
waste.

Bioccnyersign  Systems  - Bioconversion is a biological method of
removing pollutants from waste water.  Its use  involves  one  or
more of the following:

1.  Aerated lagoons
2.  Extended aeration
3.  Activated sludge
4.  Contact stabilization
5.  Trickling filters

While   both   aerobic   and   anaerobic   sludge  digestion  are
bioconversion processes, they are not used to  remove  pollutants
directly  from  the  waste  stream  but  rather  to further treat
materials already removed or currently being generated as a  part
of the treatment operation.  Bioconversion units based on the use
of activated sludge or one of the basic modifications thereof are
designed  on  the basis of 90-363 mg (0.2-0.8 Ib) of COD per 0.45
kg (1 Ib)  of dry biomass.   Depending  upon  the  nature  of  the
organics, this loading will provide average removals in excess of
80-90  percent  with daily maximum discharges not exceeding three
times  the  average  discharge.   Trickling  filter  systems  are
designed  in  a  more  empirical  fashion  using  one of the many
formulae in the literature relating efficiency to a real  loading
depth, recycle rate and hydraulic load.

Carbon Adsorption Systems - These are of two general types; those
which  use  a  more or less fixed carbon bed, and those which use
powdered carbon and recover the spent carbon in  an  accompanying
clarifier.   The  carbon  is  usually loaded at rates of 45-227 g
(0.1-0.5 Ib)  of pollutant per 0.45  kg  (1  Ib)   of  carbon.   At
conventional  surface  loadings,  spent powdered carbon is easily
recovered in a clarifier after coagulation with  inorganic  salts
or organic polyelectrolytes.

Carbon  regeneration  is  a  comparatively  new  art.  While some
regenerative type systems do exist, they are neither  common  nor
completely  satisfactory,   In  carbon  regeneration, there are a
number of technological questions  still  to  be  answered.   For
example,  movement of the carbon to the furnace, attrition rates,
control of oxygen to prevent explosion.  All of  these  questions
should  be  carefully  examined  prior  to  entering upon a major
program utilizing the carbon adsorption waste treatment  process.
However,  if  the  nature  of  the  wastes  to be treated clearly
indicate  the  desirability  of  using  the  process,  the  above
considerations should not be viewed as absolute deterrents.

Filtration  for  Removal  of Suspended Solids _ See discussion of
oil"removal.
                               98

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Dissolved Solids Removal - The design of systems for this purpose
varies widely with the manufacturer.  They are evaluated  on  the
basis  of efficiency, water recovery, and the tendency to foul in
the presence of suspended material.   Most  systems  require  the
removal of most of the suspended solids prior to treatment.  Some
require  virtually  complete removal of both suspended solids and
dissolved organic solids.  Over-all water recovery tends to  vary
from  65-90 percent depending upon the particular system employed
and the nature of the waste.

Other Treatment Technique Considerations - In a good part of  the
soap  and detergent industry, the conversion of raw materials and
the recovery of reaction by-products is carried out  on  a  batch
rather than a continuous basis.  This results in effluent streams
which  flow  sporadically and vary greatly in content and volume.
Because of this, most soap and detergent plants have devised ways
of offsetting such irregular performance and  obtaining  effluent
streams  of  a  more  constant  nature, usually by providing some
system capacitance, frequently in the  form  of  an  equalization
basin.

while  it  is not recommended that provision be made specifically
for the control of phosphorus, it is recognized  that  a  certain
amount of phosphorus is normally degraded in the normal course of
waste  treatment.   The  following  discussion  is  presented  to
indicate how this occurs.

When in the coagulation and sedimentation waste treatment process
lime, alum, or a combination of iron salts is used as the primary
coagulant for the removal of suspended or colloidal material, the
removal of phosphorus may be carried out concomitantly by  making
minor  adjustments  in  the mode of operation and the handling of
the sludge.  In many cases, a high  degree  of  removal  will  be
obtained  with no change in the standard operating practices.  It
depends upon the pH levels employed in lime coagulation  and  the
level  of  aluminum  or  iron  salts  employed in polyelectrolyte
coagulation.  In general, this procedure will produce  phosphorus
levels  well  under  1 mg/1 and under 0.5 mg/1 where an extremely
high level of sedimentation performance is obtained.

In the above mentioned waste treatment process,  some  phosphorus
is  removed as the phosphate salt of the metal cation employed in
the coagulation step.  In the  case  of  lime  precipitation,  pH
values  in  excess of 9.5 are generally required for a high level
of removal.  The actual value depends on the  background  calcium
in  the  waste  stream and the level of removal required.  In the
case of ferric or aluminum phosphate precipitation, 1-3 times the
stochiometric quantity will be required  for  a  high  degree  of
removal.   As  can  be  seen, these quantities of material do not
represent a major  addition  to  the  chemical  requirements  and
indeed  a  high  level  of phosphate removal may be incidental to
suspended and colloidal solids removal.  Where phosphorus removal
is practiced as a part of an over-all waste  treatment  operation
which  includes  bioconversion,  a sufficient level of phosphorus
                               99

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must remain in the stream flowing to  the  biological  system  to
support  microbial  action.  On a weight basis, this is generally
of the order of 200 units of COD for each unit of phosphorus.

To facilitate an understanding of the  relationship  between  the
various  unit  processes involved in the over-all waste treatment
process, the former have been arranged in the  approximate  order
in  which  they  might  occur in a composite waste treatment flow
chart in Figure 20.  A similar chart for sludge  solids  handling
is presented in Figure 21.

SPECIAL OPERATIONAL ASPECTS OF CONTROL TECHNOLOGY

The  nature of the treatment scheme proposed herein, coupled with
certain basic characteristics of the industry itself,  calls  for
special  design  and  operating  techniques  in  order to achieve
satisfactory waste control.  The factors involved  are  discussed
briefly in the following paragraphs.

The  industry employs many batch operations which tend to produce
waste of variable character  and  quantity.   As  a  consequence,
there  is  often  a need for some way of obtaining a more uniform
waste stream from the standpoints of both composition  and  flow.
Traditionally this has been done by installing mixed equalization
tanks  through  which the wastes pass prior to being subjected to
the principal treatment.   However,  these  units  often  present
operating problems of their own.  For example:

1.   If  the  waste  is  not  at biostatic concentrations when it
reaches the treatment plant, some bacterial growth will occur  in
the  equalization unit producing solids and tending to reduce the
oxidation potential of the  system  to  ineffective  levels  with
accompanying odors and nuisance status.

2.   It  is  necessary  to  provide  a  minimum of 0.8 kw/cum (40
hp/1000 gal) to be sure that the wastes in the equalization  tank
are completely mixed and that sedimentation will not occur.

On  the other hand, if an equalization unit is not provided, unit
operations  and  processes  which  are  regulated  by  flow   and
concentration  will  be  adversely  affected.   In  minimizing or
eliminating the adverse effects of influent surges, the following
should be considered:

1.   Installation  of  clarification  units  which  can  be  kept
uniformly  over  4  m (12 feet) side water depth.  Deep units are
much less subject to upsets by variations in surface loading than
are shallower units of 3 m  (10 ft) or less.

2.   If  a  completely  mixed  first   stage   activated   sludge
bioconversion  system  is  to be employed it should be understood
that the effluent quality will vary with  the  influent  strength
surges.   Effluent  quality  variations  can be handled either by
equalization, or by providing a second activated sludge stage  of
                               TOO

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                                      COMPOSITE FLOWSHEET
                                        WASTE TREATMENT
                                   SOAP & DETERGENT INDUSTRY
                                                           TO REGENERATION
                                                                                       BRINE
RAW
WASTE'
COAGULATION

SEDIMENTATION
BYCONVERSION
                                                   SLUDGE-RECYCLE
               GREASE & OIL RECOVERY
                                                SLUDGE CONDITIONING
                                                      AND
                                                     DISPOSAL
SAND OR
MIXED MEDIA
FILTRATION
                                               FIGURE   20

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                SLUDGE SOLIDS HANDLING
                SOAP & DETERGENT INDUSTRY
SLUDGE FROM OILY
WATER TREATER
       SLUDGE FROM
COAGULATION & SEDIMENTATION
       OVERFLOW TO
       PROCESS
                                   OVERFLOW TO
                                        PROCESS
                                     WASTE SLUDGE
                                     FROM BIOCONVERSION
                                     SYSTEM
                                                THICKENING
                          THICKENING
                                                    \r
                         DEWATERING
                         VACUUM FILTER
                         OR CENTRIFUGE
                              T
                                              TO LAGOON


                                                OVERFLOW TO
                                                PROCESS
                                            HEAT
                                            TREATMENT
                                             LAGOON
                                             DISPOSAL
                       CAKE TO INCINERATION
                       OR GROUND DISPOSAL
      GROUND
           1
      DISPOSAL
      ASH TO LANDFILL
      OR GROUND DISPOSAL
                                             INCINERATION
102
                          FIGURE  21

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the   plug   flow   type.    Since  the  energy  per  unit/volume
requirements for either option are roughly comparable, the latter
procedure is generally the most cost effective means  of  dealing
with this problem.

If  carbon adsorption is to be employed instead of bioconversion,
an equalized feed stream will be necessary.  Regardless of  other
considerations,  an  upstream system capacitance must be provided
if maximum efficiency is  to  be  obtained  from  the  treatment.
Whenever  the waste entering a coagulation and sedimentation unit
tends to be highly biodegradable, troubles with  gasification  in
high  solids  systems may be anticipated if neutral pH values are
employed for coagulation.  Therefore, it is necessary to evaluate
the residence or holdup of solids that can be employed, prior  to
deciding  upon a treatment system.  Plant shutdown for turnaround
or under emergency conditions, particularly if  operations  cease
for  more  than  two to three days, can result in a diminution in
the effectiveness of bioconversion  systems  on  startup.   Under
such circumstances, the advantages of having an equalization unit
of  substantial  size  ahead  of  the  bioconversion  unit become
apparent.   During  turnaround,  the  equalization  unit  may  be
drained   and  cleaned,  thereby  providing  the  food  materials
necessary to sustain the  resident  biota  in  the  bioconversion
portion of the system.  If this is not possible, provision should
be  made  for  the  discharge of stored concentrated waste to the
biocenversion unit during plant shutdown.

The equipment associated with the treatment steps proposed herein
does not have  extraordinary  maintenance  requirements.   Normal
once per year examination, along with routine maintenance, is the
standard requirement,  consideration should be given to providing
unit  by-passes  or the utilization of design concepts which will
permit  routine  maintenance  without  taking  the  unit  out  of
service.   It  should  be  generally  possible  to  by-pass  each
individual unit without taking the plant off the line or markedly
changing the over-all operational efficiency.

Waste treatment  works  must  be  well  managed  to  avoid  their
becoming public nuisances.  If not handled properly, lagoons, the
incineration  of  sludge,  or  the  regeneration  of  carbon  may
generate objectionable odors.  This problem may be eliminated  or
controlled  by  proper  location  of the units and the use of gas
emission control equipment.   In  the  case  of  lagoons,  proper
operation of the preceding waste treatment units is essential.


Solid Waste Generation Associated with Treatment Technology

Depending  on  the  precise  nature of the over-all waste stream,
solid waste may orginate at any one  of  several  points  in  the
waste  treatment  process.   Please  refer to the composite waste
treatment flow sheet.  The principal sources of solid waste are :
                                103

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1.  Sludge from the under flow  of  a  gravity  type  oily  water
treater.  This sludge would normally be combined with other waste
solids from the process.

2.   Sludge withdrawn from the coagulation and sedimentation unit
and combined with other waste sludges or processed separately.

3.  Waste sludge which is normally generated in  a  bioconversion
facility  although  the units can be designed to approach virtual
steady state between  new  sludge  production  and  the  loss  of
resident sludge over the weir and through endogenous respiration.

Process  sludges  are  treated  by  one  or  more  of the methods
outlined in Figure  21.   In  rough  chronological  order,  steps
leading to the ultimate disposal or sludge include the following:

1.   As  a  first  step,  the  sludge  is  thickened in a gravity
thickener or a centrifugal  device.   In  either  case,  effluent
solid  concentrations varying from 3 percent to 10 percent may be
anticipated..   The  difference  arises   from   the   substantial
differences in the characteristics of the sludges.

2.  After thickening, biological sludges may be treated to reduce
moisture  content  of  the  ultimate  cake.   The  sludge is then
subjected to heat and pressure to reduce the size and  complexity
of  the  protein  and  carbohydrate  cellular material.  This, in
turn,  releases  bound  water.   In  some  cases  the  sludge  is
discharged to a lagoon after this step.

3.   In  the  next  step,  the sludges are dewatered, either on a
vacuum filter or in a solid bowl centrifuge.  In  some  instances
sludges  will have to be conditioned with either organic polymers
or inorganic polyelectrolytes prior to dewatering.

4.  Following the dewatering step the sludge may be  disposed  of
directly  or  incinerated for the removal of virtually all of the
residual organic matter.

5.  Following incineration the  ash,  which  constitutes  from  5
percent to 10 percent of the initial mass, is disposed of as land
fill.
                              104

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                          SECTION VIII

           COST, ENERGY AND NON-WATER QUALITY ASPECTS
There  are fewer than a dozen plants associated with the soap and
detergent manufacturing industry  which  are  point  source  dis-
chargers  into navigable waters.  Of these plants, only one has a
complete primary-secondary treatment plant  comparable  to  those
found  in  a  good  municipal sewage treatment system.  There are
several aerated and non-aerated lagoons which experience  varying
degrees  of  success in their ability to reduce the incoming load
to acceptable levels.

Because of the highly variable nature of the wastes  which  makes
individual  treatment  prohibitively  expensive,  most  small and
medium-size  plants  will  continue  their  current  practice  of
sending  their wastes to municipal or regional systems.  For this
reason emphasis in this  section  has  been  placed  on  in-plant
controls rather then end-of-pipe treatment.

IN-PLANT CONTROL

There  are  essentially three sources of in-plant contaminants of
the waste water effluent streams.  They are:

     1.  Impurities removed from raw materials
     2.  By-products or degradation products made
         in the process
     3.  Very dilute product (in aqueous solution)
         resulting from leaks and spills and the
         clean out of equipment.

These are discussed in the succeeding paragraphs.


                             TABLE 4

                  Range of Water Use by Process
                 (gal/1000 Ib Product Produced)
                 (liters/119kg Product Produced)

Batch Kettle Soap                                25 - 2345

Fat Splitting                                   203 - 23,200

Soap Via Fatty Acid Neutralization               31 - 1750

Glycerine Concentration                          80 - 120,000

Glycerine Distillation                           40 -  65,000

Bar Soap                                          9 - 2300
                                 105

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Oleum Sulfonation                                12 - 90

Air/303 Sulfonation                               1 - 240

Chlorosulfonic Acid Sulfonation                 184 - 330

Neutralization                                    2 - 1100

Spray Dried Detergents                           14 - 228

Liquid Detergents                                75 - 185

Drum Dried Detergents                           265 - 400

Detergent Bars & cakes                          circa 25


Impurities Removal

There are two  main  sources  of  impurities  which  concern  the
manufacturers  of  soaps and detergents.  They are the light ends
and color bodies in the fats and oils used in the manufacture  of
soap,  and  the  light  ends  (usually low molecular weight fatty
acids)  removed in the flashing and/or distillation of fatty  acid
produced  from  the  fat  splitting  process.   In both cases the
processes  having  high  effluent  loadings   employ   barometric
condensers.   Replacement  of  barcmetrics  by surface condensers
would appreciably reduce the amount  of  contamination   (approxi-
mately  80  percent)  and, of course, all but eliminate the entire
hydraulic loading.  The capital cost of  this  replacement  would
amount  to  approximately  $2,00-$3,00/1000 Ib annual capacity of
fatty acid in a plant capable of making 100  million  pounds  per
year  having  other  capital cost about $60-$70/1000 Ib of annual
capacity.  This, however, is  not  the  only  way  in  which  the
effluent  problem  could  be  minimized.   An  alternative  is to
install an extractive step ahead of the barometric leg where  the
light ends are picked up in an oil film to be later distilled for
the  recovery  of  the  valuable  low molecular weight acids.  An
installation  of   this   type   has   been   proven   successful
commercially.   It  has  a  two  year payout.  An initial capital
investment of approximately $7-9/1000 Ib annual capacity of fatty
acid produced would be required for a  20  million  Ib  per  year
plant.    A  reduction  in  raw waste loadings of approximately 85
percent would be attained.

Still another method of handling the problem is the  installation
of  a  cooling  tower  with recirculation of condenser water, and
employing a fat skimmer.  A periodic blowdown of the  skimmer  to
sewer   would  dispose  of  accumulated  solubles,  and  the  fat
recovered would assist in the  payout.   The  cost  for  such  an
installation  would  be  approximately  $10-12/1000  Ib of annual
capacity for a 40 million Ib per year plant.   Reduction  of  raw
waste  loadings of approximately 75 percent would be anticipated.
Improved performance (approximately 90S removal of both  floating
                                   106

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and  emulsified  oil  and  grease) of skimmers can be attained at
modes costs by providing chemically  assisted  flotation.   While
this  will  not  improve  removal  of emulsified coconut oils, it
should be borne in mind that coconut oils constitute 20% or  less
of the feedstocks.

Although  not strictly an impurity, glycerine is carried overhead
into  the  barometric  condenser  water   in   the   process   of
concentrating  and  subsequently  distilling  the  product out of
dilute feeds.  It is estimated that the  cost  of  replacing  the
barometric  legs  with  surface condensers and appropriate vacuum
equipment would amount to about $21/1000 Ib  annual  capacity  of
glycerine  and  would reduce raw waste loads by about 90 percent.
This compares with a total cost  of  around  $40/1000  Ib  annual
capacity  for  installation of concentrators utilizing barometric
condensers.  The payout for the  surface  condenser  installation
(based  on the additional product recovered) is around 10+ years.
These estimates apply to a plant having a 10 million Ib per  year
glycerine capacity.

Unfortunately,  installation  of  a  recirculating  cooling water
system would have no effect upon the effluent  loadings  in  this
case  since  glycerine is soluble in water in all proportions and
recirculation would only result in higher concentrations in lower
volumes of water.  This could be offset by operating the  cooling
tower  as  a  biological  tower to reduce organics.  Further, the
reduced hydraulic load can be treated at  lower  costs  and  with
greater   efficiency   in   the  typical  end-of-pipe  biological
treatment systems.

By-product/Degradation Product Control

The dark colored soap (nigre)  recovered from  batch  kettle  soap
making  can in some instances, constitute a disposal problem.  In
the larger, more integrated plants there is usually a market  for
the  material  (e.g.  pet soap and industrial lubricants) so that
the disposal of the material is not  a  total  liability.   where
this  is  not  the case a modest investment would need to be made
for an accumulator tank where these materials could be acidulated
to break the soap, the fats being  recovered  and  sold  and  the
balance  of  the  aqueous  layer  being  sent  to  disposal.   An
investment of about $2 - $4/1000 Ib annual capacity of soap would
be needed for this operation.    This  is  not  an  inconsiderable
amount  when  related  to an already fully amortized older plant,
but it would result in about 75 - 80  percent  reduction  in  raw
waste load.  If the fat is recovered, an ultimate payout could be
realized.

Degradation  of product occurs most abundantly in the sulfonation
processes, particularly in the start up of an air-sulfur trioxide
unit.  In large integrated plants this causes only minor problems
since they can often work off  the  relatively  small  amount  by
blending it into a large volume material.  The small scale custom
sulfonator is the one of concern.   He has no economic alternative
                                 107

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but  disposal  to  sewer.   Use of a batch countercurrent process
with improved agitation can give improved heat transfer  as  well
as  increased contact of reactants.  This can be achieved with an
almost undiscernible cost.  In this case, the added capital  cost
would  amount to about $2.20/million kg  ($l/million Ib) of annual
capacity.  Utilities consumption  would  increase  less  than  10
percent  from utilization of a recycling loop for the neutralized
sulfonic acid product stream.

Dilute Product From Cleanouts, Leaks & Spills

Liquid detergent manufacture at present accounts for one  of  the
higher  waste  water  effluent loadings in the industry.  This is
related to the need to clean out the  mixing  tanks  and  filling
lines  thoroughly  when  making  a  product change in the filling
operation.  If steam or air  (rather than water)  were used to blow
the lines clean, the product could be directly reused, or in  the
case of steam the more concentrated solutions could be stored and
either reused or disposed of more easily.  The cost to the larger
highly  integrated  plants (50 million Ib per year with a capital
cost of $25-30/1000 Ib of annual capacity) would amount to  about
$2  -  $3/1000  Ib annual capacity of anhydrous product produced.
Resulting raw waste loads reduction on the order of 50 percent or
greater should be realized.

Additional major sources of dilute product streams are  detergent
spray  towers'  air  scrubbers and tower clean outs.  A suggested
way  in  which  this  could  be  reduced  involves  incorporating
concentrated  and dilute scrubbing streams in series to chill and
scrub the exit gases from  the  tower.   The  concentrated  first
stage  scrubber  stream would be recycled to the crutcher and the
dilute second stage scrubber stream used  for  the  first  stage.
The  capital  cost  would  amount  to  about $1.00/1000 Ib annual
capacity for spray towers capable of producing 100 million Ib per
year.  This includes cooling  facilities  to  keep  the  scrubber
water  down  to  an  effective  chilling  temperature.  Raw waste
reduction should be approximately 65 percent.

END OF PIPE TREATMENT

Waste water streams from soap and detergent processes are readily
biodegradable, but they do not have uniform flows nor  are  their
concentrations  constant.   In  most  cases there are significant
surges having varying strengths of  contaminants.   This  set  of
conditions  is  very detrimental to the successful operation of a
treatment system.  For this reason, small scale operators  having
intermittant  streams of 10,000 - 50,000 gallons per day of waste
water are almost without alternative to utilization of  municipal
sewer systems.

Packaged,  off the shelf units, at a cost approximating $600/1000
gal/day, could indeed handle the load for a  small  plant  if  it
were  consistent  in  quality,  concentration, and flow.  None of
these conditions, however, describe the waste  waters  associated

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                                              Table 5

                                 Cost and Energy Requirements Associated

                                      With Various Treatment Methods
o
to
       Treatment Procedure
                    Costs
                       Power Requirements
                          Capital
                          Operational
Oil & Grease
  Removal

Hand skimmed
   tanks      $26-79/1000 1
             ($100-300/1000 gal.)

Mechanically
cleaned tanks $13-18/1000 1
             ($50-70/1000 gal.)

Mixed media
filtration    $21-66/1000 1
             ($80-250/1000 gal.)
        Flotation


        Carbon
        adsorption
 $11-37/1000  1
($49-140/1000 gal.)
 $26-210/1000 1
($100-800/1000 gal.)
                                           $5.00/day
                                             None
 $0.008-0.026/1000 1   0.19-0.57 kw/1000 cu m/day
($0.03-0.10/1000 gal.) 1-3 hp mgd


 $0.032-0.105/1000 1   1.52-2.85 kw/1000 cu m/day
(0.12-0.25/1000 gal.)  8-15 hp/mgd

 $0.03-0.11/1000 1     1.14-2.85 kw/1000 cu m/day
($0.12-0.40/1000 gal.) 6-15 hp/mgd
 $0.22-0.66/kg oil
($0.10-0.30/lb oil)
                                                          0.95-1.9 kw/1000  cu m/day
                                                          5-10 hp/mgd

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                                    Table 5
                                    (cont'd)
Treatment Procedure
                    Costs
                       Power Requirements
                   Capital
                          Operational
Carbon Adsorption
System

Fixed carbon
in column     $26-79/1000 1
             ($100-300/1000 gal.)

Powdered car-
bon fed prior
to coagulation
& sedimentation
void
              $6-26/1000 1
             ($25-100/1000 gal.)

Final
Clarification $13-40/1000 1
             ($50-150/1000 gal.)
Effluent
Filtration
 $21-69/1000 1
($80-260/1000 gal.)
Reverse Osmosis
Systems£79-158/1000 1
             ($300-600/1000 gal.)
                       $0
                      ($0
   ,04-0.132/1000 1
    15-0.50/1000 gal.)
                   0.95-1.9 kw/1000 cu in/day
                   5-10 hp/mgd
                       $0.
                      ($0,
                       $0,
                      ($0,
 $0.
($0.
                       $0,
                      ($0,
    04-0.132/1000 1
    15-0.50/1000 gal.)
    008-0.019/1000 1
    03-0.07/1000 gal.)
013-0.040/1000 1
05-0.15/1000 gal.)
    079-0.269/1000 1
    30-1.00/1000 gal.)
                   0.95-2.85 kw/1000 cu m/day
                   5-15 hp/mgd
                   0.19-0.57 kw/1000 cu m/day
                   1-3 hp/mgd
0.95-1.9 kw/1000 cu m/day
5-10hp/mgd
                   190 kw/1000 cu m/day
                   1000 hp/mgd

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                                    Table  5      (cont'd)


Treatment Procedure       	Costs  	     	 Power Requirements
                   Capital             Operational

Suspended Solids
Removal

Coagulation &
sedimentation $13-40/1000 1         $0.013-0.024/1000 1   0.19-0.57 kw/cu m/day
             ($50-150/1000 gal.)    ($0.05-0.09/1000;gal.) 1-3 hp/mgd

Chemical
addition                            $0.003-0.013/1000 1
                                    ($0.01-0.05/1000 gal.) Fractional mgd

Mixed Media
Filtration & Flotation - See Oil & Grease Removal

Bioconvers ion
Systems

Activated
sludge        $29-73/1000 1         $0.013-0.039/1000 1   19-95 kw/1000 cu m/day
             ($110-275/1000 gal.)   ($0.05-0.15/1000 gal.) 100-500 hp/mgd

Aerated Lagoons
              $28-53/1000 1         $0,016-0.029/1000 1   19-95 kw/1000 cu m/day
             ($70-2000/1000 gal.)   ($0.04-0.12/1000 gal.) 100-500 hp/mgd

Extended
aeration      $21-79/1000 1         $0.013-0.053/1000 1   19-95 kw/1000 cu m/day
             ($80-300/1000 gal.)    ($0.05-0.20/1000 gal.) 100-500 hp/mgd

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                               Table 5 (cont'd)


-Power  cost taken at $0.01 KWH
-Attendance @ $5.00/hour
-Manufacturer data used for power requirements
-Plant  sizes are generally across 0.01-0.19 kw/1000 cu m/day  (0.1-1.0 MGD)  to show
 cost variation and economy of scale.

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with  operations  of  the  conventional small or large plant.  An
alternative could be the installation  of  a  large  equalization
basin,  but  it  would  be  prohibitively  expensive  for a small
operation.  Further, the typical plant is usually  located  in  a
metropolitan  area where the availability of enough land poses an
insurmountable problem.

In plants having  daily  flows  of  about  500,000  gallons,  the
capital cost for end of the pipe treatment can be expected to run
around $2,000,000 with an operating cost approaching $900/million
gallons.   Best practicable control treatment currently available
would most likely include chemical precipitation and equalization
followed by an activated sludge unit and final clarification.   A
viable  alternative  for small plants is an aerated lagoon.  Such
lagoons  should  have  40-50  hp  aeration  per  million  gallons
capacity  and  some  provision  for  clarification  of  the final
effluent with return of the sludge to the lagoon.

Best   available   technology   economically   achievable   would
incorporate  a  final  polishing  operation,  such as mixed media
filtration or carbon absorption,  or  a  second  stage  activated
sludge  unit  with  plug  flow  operation.  Incorporation of such
polishing steps should result in at  least  50-75%  reduction  of
pollutants   contained   in  the  effluent  from  the  biological
treatment and reduce variability in the quality of discharge.

ENERGY REQUIREMENTS

With the  introduction  of  surface  condensers  to  replace  the
barometrics,  utility  costs  (including  power)   will  increase.
Generally, in  those  processes  requiring  capital  modification
because of guideline recommendations, the utility costs will rise
an average 222/1000 Ib of product manufactured.  About It of this
is  due  to direct power needs, the rest being for steam, cooling
water, etc.

As might  be  expected,  the  processes  impacted  the  most  are
glycerine  concentration  and distillation which amounts to about
$7,80/1000 Ib.

NON-WATER QUALITY ASPECTS

There is  very  little  non-waterborne  waste  generated  in  the
production  of soaps and detergents.  Almost all (99+ percent)  of
the raw materials entering the soap and detergent  processes  end
up  as  packaged products for sale to the household or industrial
consumer.  Modest amounts of solid  wastes  end  up  in  sanitary
landfill operations.

In  the  operation  of  dry  filling  lines  there are infrequent
problems with the mechanical equipment  that  result  in  damaged
cartons.   This same problem applies with many of the operations,
including  warehousing.   Wherever  possible,  the   product   is
recycled  back  into  the manufacturing process unless it becomes

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excessively contaminated.  At  most,  one  would  expect  several
hundred  pounds  per day of solid wastes being sent to a sanitary
landfill for disposal from a large plant.

During spray drying tower cleanouts, there often will  be  caked,
charred  material  unsuitable  for recycle.  This would amount to
about 1000 Ib per week from  a  very  large  plant;  again,  this
material would be sent to a sanitary landfill.

Sludge  from  waste  water  treatment  will also be an input into
sanitary landfill operations.  One system in operation pumps  the
sludge  from  the  biotreater  into the chemical treater where it
precipitates with the addition of lime.  The settled  precipitate
is  pumped  to  a  settling basin where the sludge builds up to a
depth worthy of disposal, whereupon the "solids" are  then  taken
to the landfill.

Conversion   of  air  contamination  problems  into  waste  water
problems is on the increase in the soap and  detergent  industry.
Soap  dust  from bar soap manufacture, and fines in exit air from
the detergent spray tower are being dissolved in  scrubber  water
to be ultimately treated in sewage systems.  This is an ideal way
to   maximize   the  disposal  alternatives.   The  products  are
biodegradable and readily handled in  already  existent  standard
treatment facilities.

IMPLEMENTATION OF TREATMENT PLANS

The  equipment  required  for  implementing  the waste treatments
discussed in the preceding sections of this report are  available
as  off-the-shelf  items  or  they may be found in manufacturers'
catalogs.  In the present economy the  construction  manpower  is
generally  available,  although  short  term  local variations in
availability are to be expected.  However, virtually all  of  the
work  required  would  be  carried  out by the general contractor
normally involved in the construction of  sewage  and  industrial
waste treatment works.

Depending  upon the waste treatment employed and the precise unit
process under consideration, the land requirements will vary from
as little as one-half acre to as much as three or four acres.  It
is likely that, for the industry as a whole,  a  good  mean  land
requirement  would  be  of the order of 0.4 to 0.8 ha (one to two
acres).

The basic costs and relative efficiencies of the waste  treatment
processes  outlined  in  the composite waste treatment flow chart
have been summarized in Table 5.  The capital and operating costs
were derived from  actual  plants  which  have  been  constructed
within  the  past  few years.  The higher range costs and capital
are applicable to waste water flows of 50,000 -  100,000  gallons
per  day.  The lower end of the range is applicable to volumes of
2-3 million gallons per  day.   The  data  in  the  table  were
adjusted upward and expressed in terms of 1972 dollars.

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Regarding  operational  costs, the figures cited are direct costs
only.  They do not include any administrative,  overhead,  fringe
benefits  or directly charged laboratory support.  If these costs
were to be included, the total would be roughly double.

Sludge conditioning  and  disposal  costs  are  highly  variable,
depending  upon  the  nature  of  the  sludge  and the procedures
followed.  The cost brackets for the sequences outlined in Figure
20 are shown in Table 6.  It is assumed that  land  is  availabl
for lagoon and landfill disposal of sludge and ash.
                                 115

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                                     Table 6

                      Cost of Sludge Conditioning and Disposal Operations
Procedure
                                Costs
                          Power Requirements
1.  Thickening-
    influent at
    5000 mg
2.   Lagooning

3.   Heat Treatment
                      Capital
                                             Operational
                  $1800-6400/metric ton
                  ($2000-7000/ton)
    $1.60-6.40/metric ton   Fractional/tpd
   ($1.80-7.00/ton)
                  Depends upon land cost entirely
                  $13,640-45,400/metric
                 ($15,000-50,000/ton)
ton $4.50-13.60/metric ton
   ($5-15/ton)
181-454 hp/tntpd
200-500 hp/tpd
Dewatering

4.
Vacuum Filtration $103-297/m2
                 (95-275/sq ft)
5.   Centrifugation
6.   Incineration
                  $455-909/mtpd
                 ($500-1000/tpd)

                  $136,400-681,800/mtpd
                 ($150,000-750,000/tpd)
    $7.30-31.80/metric ton
   ($8-35/ton)

    $4.55-22.70/metric ton
   ($5-25/toh)

    $4,55r22.70/metric ton
   ($15-50/ton)
22.7-68.2 hp/mtpd
22-75 hp/tpd

45.5-90.9 hp/mtpd
50-100 hp/tpd

182-273 hp/mtpd
200-300 hp/tpd

17.2-68.9 1 of
fuel oil/metric
ton (5-20 gal.
fuel oil/ton)

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                           SECTION IX

               BEST PRACTICABLE CONTROL TECHNOLOGY

                       CURRENTLY AVAILABLE

Introduction

One  of  the first steps in the development of guidelines was the
determination of raw waste loadings in the waste water flows  for
each  subcategory in terms of kg/kkg (Ib of pollutant/1000 Ib) of
anhydrous product produced in that subcategory.   The  raw  waste
loading  to  be expected from the best practicable technology was
established and the  guidelines  values  defined  as  appropriate
reduction  of  the raw waste load, e.g., reasonable expectancy of
any treatment  plant  having  a  biological  secondary  treatment
process to attain 90 percent reduction of BOD5.

Wherever appropriate, attention was given to in-plant controls to
minimize  the  raw  waste  load.   Thus, best practicable control
technology may  be  defined  as  good  current  in-plant  control
followed   by   an  end-of-pipe  system  consisting  of  adequate
equalization,  efficient  biological  treatment  (e.g.,  extended
aeration)  and final clarification.

For  several  soap and detergent processes a negligible discharge
has been achieved by most manufacturing plants.  Best practicable
control technology currently available guidelines  give  each  of
these  processes  a  very  small  but  finite  effluent allowance
because of one or more of the following reasons:

1.  The product in the effluent stream is so degraded it would
    be unsuitable for incorporation in the final product and must
    thus be disposed of.
2,  The waste water source is so dilute as to require undue amounts
    of heat energy to recover the dissolved solids content.
3.  The material in the waste water is quite biodegradable; there-
    fore,  it is readily handled by the receiving treatment plant.

In  those  categories  where  the  guidelines   have   been   set
particularly  low,  the  permit  writer  should  be  alert to the
occasional need to make spot increases in these  limits.   Upsets
and  mechanical  problems  requiring  cleanouts may crop up, rare
though they may be.  This will be particularly critical for small
plants (under $500,000 in gross proceeds).  The larger integrated
plants have sufficient flexibility in their  ability  to  recycle
the  contents  of  waste  streams to minimize their need for spot
increases.

In a few processes there are some relatively heavy discharges  of
salt and sodium sulfate.  No limit has been established for these
very low toxicity materials since (1)  they will be highly diluted
by  other process effluents before becoming a point discharge and
(2) the permit writer  will  undoubtedly  want  to  evaluate  the
                                   117

-------
background  levels  in  the  receiving
levels, if any, should be established.
waters and determine what
No maximum delta  temperature  was   established   since  the  dif-
ferential  between inlet and outlet  process water temperatures is
quite modest, at most around 17°C  (30°F),  and much  of  the  heat
would be dissipated in the waste treatment process.

The  interrelationship of air and water  pollution problems became
quite  apparent  in  this  study.    Increasingly   stringent   air
emission  standards  have set performance  requirements beyond the
ability of dry recovery  systems  available  on   detergent  spray
towers.  Wet scrubbers have been employed  which now  allow the air
effluent  to  meet  those  standards, but  result  in  a substantial
water flow and a correspondingly higher  water pollutant loading.

In every instance in the following   guidelines,   the  pH  of  the
point  source  discharge  is  required to  be between 6.0 and 9.0.
With but few exceptions this  requirement  will   be   met  by  the
mingling  of  individual  raw  waste streams  in the  treatment
facilities and will not require special  pH adjustment.

SOAP MANUFACTURING

101 - SOAP MANUFACTURE BY KETTLE BOILING

General

This ancient art has been carefully  scrutinized   by   all  of  its
practitioners   to  minimize  cost   and  the  avoidable  loss  of
marketable products where the installed  capital permits.  Even in
the area of very high quality soaps  there  still appears to  be  a
preference for this well established process.

There  are  essentially two main streams carrying away waste from
this source (in actual practice  there   may  be   more  subsidiary
sources).   They  are  typified  by  the  blocks  indicated in the
simplified flow diagram given below:
                               r	=>	Neat Soap
Fats &
Oils

->--
Solid
Waste
Pre
Treatment
— 1 ^,
Liquid
Waste


->-
Kettle
Boil
J, L
Spent
Lye
•I

*— ^Rec)
v
rcle 1

[Nigre U_

Glycerine
Recovery




Refining [,.
>
t
Dark Soaps
to Market
Soap Scrap
Recycle

                                   Liquid Waste



                  WASTEWATER SOURCES IN SOAP MANUFACTURE

                            FIGURE 22
                                118

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The liquid waste from fat pretreatment will normally be a fat  in
water  emulsion  of modest BOD5_, with perhaps some clay and other
organics.  However, the stream from nigre processing, often  just
a  purge,  will  be  very  rich  in  BOD5 and contain some sodium
chloride and sodium sulfate.  Some soap manufacturers do not,  at
present,  completely  process  their nigre but run it directly to
sewer.  This is  a  point,  for  some,  to  improve  in  effluent
control.

Raw Waste Loading

The  following  are  the  expected  thirty  day average raw waste
loadings which would be entering a waste treatment plant:

BOD5 - 6 kg /kkg    (6 lb/1000 Ib) anhydrous soap

COD - 10 kg /kkg    (10 lb/10001b) anhydrous soap

Suspended Solids - 4 kg /kkg    (U lb/1000 Ib)  anhydrous
                   soap

Oil and Grease - 0.9 kg /kkg    (0.9 lb/1000 Ib)
                 anhydrous soap


Best^Practicable Control Technology Currently Available Guidelines

On a thirty day average basis the following parameter values  are
recommended:

BOD.5 - 0.60 kg/kkg (0.60 lb/1000 Ib) anhydrous soap

COD - 1.50 kg/kkg  (1.50 lb/1000 Ib) anhydrous soap

Suspended Solids - O.40 kg/kkg  (O.UO lb/1000 Ib)
                   anhydrous soap

Oil and Grease - 0.10 kg/kkg (0,10 lb/1000 Ib)
                 anhydrous soap

pH  6.0 - 9.0

In  the event of upset in either process or treatment, startup or
shutdown procedure, a value of three times that  indicated  above
should  be  considered,  provided  that over any given thirty day
period the recommended average is maintained.

Best^Practicable Control Technology Currently Available

In many soap plants there are no access points in  the  floor  to
the  sewer.  This makes good housekeeping unavoidable.  All leaks
and spills are promptly  attended  to  and  recycled  within  the
process.
                                119

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The guidelines limitations can be attained by the production (and
marketing)  of  low  grade  soap from the nigre, recovery of fats
from acidulated sewer lyes and nigre, and secondary  (biological)
treatment of the resulting waste.

Rationale and Assumptions

Fat  saponification  is  carried  out counter-currently where the
aqueous caustic stream is exhausted  in  a  final  reaction  with
fresh  fat.   At  the  other  end of the process the nearly fully
saponified fat is completely reacted by coming into contact  with
fresh  caustic.   Salt  recycle  becomes automatic in that energy
required  to  concentrate  the  glycerine  stream   automatically
concentrates  the  salt.   Filtration  of  the evaporator product
provides the recycle salt.  There is still a  substantial  amount
of salt that goes to the sewer via the bleed of the nigre.

Phase  relationships  of  electrolyte,  soap  and caustic content
largely govern their concentration and  use  to  maintain  proper
soap  solubility.   Within  these  constraints good manufacturing
management will minimize the total constituents going to sewer.

At present, this process can be brought  close  to  no  discharge
only  at the expense of the smaller soap manufacturers who do not
exhaust their nigre.  The recommended  settling  and  acidulation
tank will go a long way toward attaining this goal.

Most kettle boil soap making equipment is several decades old and
represents fully amortized capital.  The soap market is not noted
for its dynamic expansion.

102 - FATTY ACID MANUFACTURE BY FAT SPLITTING

General

The  waste  water  effluents  for  disposal come from essentially
three sources; pretreatment of the fat, light ends  emitted  from
the  fat  splitter and the fat still, and the water solubles left
in the acidulated still bottoms after the  recycleable  fats  are
removed and recovered.

The  light  ends mentioned above are found in the condensate from
the barometric condenser and include short chain fatty acids  and
unsaponifiables.   One  of  the  minor contaminants in the stream
coming from the still bottoms is the catalyst.   It  can  be  the
sulfate salt of zinc, or other alkaline earth metals.

A  simplified  schematic is given for the process to indicate the
approximate location of waste water streams.
                               120

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Fatal \


Light
Ends
Fat
Splitter
•^
Glycerine
to
Recovery
t—^—t
-distill
	 ?— '
\
— •) 	
iBottomsl j


f
Fatty Acid
to Market

Acidulation
& Settling

»
a-
To
Strea
/
ving
m
V

Hater Solubles
& Metals Salts


[Fats Recovery]
FAT SPLITTING
  FIGURE  23
     121

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The following raw waste loading can be expected:

BOD5 - 12 kg /kkg   (12 lb/1000 Ib) anhydrous acid

COD - 22 kg /kkg  (22 lb/1000 Ib)  anhydrous acid

Suspended Solids - 22 kg /kkg  (22 lb/1000 Ib)  anhydrous
                   acid

Oil and Grease - 2.5 kg /kkg  (22 lb/1000 Ib)  anhydrous
                 acid

Included in  this  loading  are  waste  water  flows  from:  fats
treatment,  fats  splitting,  fatty  acid  distillation and still
bottoms disposal.

Best Practicable Control Technology Currently Available Guidelines

On a thirty day  average,  the  following  parameter  levels  are
recommended:

BOD5 - 1.20 kg/kkg  (1.20 lb/1000 Ib)  anhydrous acid

COD - 3.30 kg/kkg (3.30 lb/1000 Ib) anhydrous acid

Suspended Solids - 2.20 kg / kkg   (2.20 lb/1000 Ib)
                   anhydrous acid

Oil and Grease - 0.30 kg/1000 Ig  (0.30 lb/1000 Ib)  anhydrous
                 acid

pH  6.0 - 9.0

No  additional  provision  need  be made for startup, shutdown or
upsets.  Allowance should be made for  a  threefold  increase  to
account  for  variability  of  treatment  over  a 24 hour period,
providing that during a thirty day period,  which  includes  this
day of high loading, the recommended average is maintained.

Best Practicable control Technology Currently Available

Essential   to  the  proper  performance  of  the  plant  is  the
incorporation  of  appropriate  fat  traps.   Indicative  of  the
technology  involved  is  the  flow chart'of a condenser/recovery
unit which could handle the load.   Note that the only effluent is
blowdown of the fat settler which handles cooling tower waters.


Due to the high temperatures maintained in the fat splitter,  fat
solubility  and  reaction rate are high so that 99 percent hydro-
lysis can be expected.  This makes separation of the  condensates
a   relatively   simple  problem,   well  within  the  engineering
capabilities of the industry.  As noted in the above  discussion.
                                 122

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it is reasonable to expect that the only materials to be disposed
of are light ends and bottoms.

Rationale and Assumptions

A  fats  recovery unit for treating fatty acid still bottoms will
help  minimize  loadings  of  effluent.   This   equipment   plus
biological  secondary  treatment  will bring the loadings down to
the guidelines level.

102 - FATTY ACID HYDROGENATION

General

As an example of the depth to which  some  technological  studies
have  been  conducted,  the  details  of fatty acid hydrogenation
processing are presented.  Due to the advanced state of the  art,
guidelines recommended are to cover all levels.

Technology for AllrLevels

Hydrogenation  of  fatty  acids  intended for soap manufacture is
regarded as an additive effluent loading  to  the  fat  splitting
operation.

The  principal  raw  materials for the manufacture of fatty acids
used in  soap  making  are  coco  and  tallow  fats.   These  are
generally  used  in  the  ratio  of about 80 percent tallow fatty
acids to 20 percent coco fatty acids in soap making.

This blend contains in the order  of  15  percent  of  the  mono-
unsaturated  oleic  acid  and  around 3-4 percent of the doubly
unsaturated linoleic acid.  There is very little  of  the  triply
unsaturated  linolenic  acid.   Twenty  percent unsaturated fatty
acids in soap is often excessive, consequently the tallow portion
of the fatty acids going  into  soap  manufacture  are  partially
hydrogenated.    This  is  particularly  necessary  since  tallow
contains up to 50 percent oleic acid esters  and  as  much  as  3
percent linoleic esters.

The  usual process of making fatty acids and the hydrogenation of
them is given in the schematic flow diagram for  the  fatty  acid
manufacture  subcategory.   The  hydrogenation process is usually
carried out batch wise, particularly for fatty acids destined for
soap making.

The hydrogen source for this process depends upon plant location.
When near a petroleum refinery the hydrogen  is  often  available
from  cracking operations and subsequently requires purification.
Hydrogen is also available from electrolytic cells  dedicated  to
electrolysis of salt for production of sodium and chlorine.

Another   common   source  of  hydrogen  is  that  from  the  de-
hydrogenation of isopropyl alcohol to make acetone.  Whatever the
                                 123

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source of hydrogen there will usually be some  alkane  impurities
that  will build up in the recycle use of hydrogen; consequently,
a bleed is necessary and is usually disposed of by burning.   This
disposition  carries  no  water  effluent  and  consequently   is
disregarded in the guidelines.

The  hydrogenation  process  requires  a catalyst.  There are two
well-known catalyst systems.   One  involves  the  deposition  of
nickel  as  nickel  formate  onto  a  pumice  or kiesselguhr or a
synthetic product  such  as  Celite.   The  other  commonly  used
catalyst  is  Raney-nickel.  Both catalysts are usually suspended
in the liquid to be hydrogenated and subsequently  filtered  out.
When  Raney-nickel is used, the spent catalyst is often recovered
and returned to the manufacturer for reprocessing.

Complete saturation of the fatty acids is not desirable  since  a
modest  amount of cross linking by oxidation helps to make a firm
soap and gives the bar good feel or hand.   Though  not  strictly
true,  the  hydrogenation  of  coco  and  tallow  fatty  acids is
described as if the same in nature.

Hydrogenation is usually carried out with the catalyst  suspended
in  the  liquid  fatty  acids  in  a  batch  process  heated to a
temperature of approximately 175 - 200 C (347 -  392  F)   as  the
hydrogen   passes  through  the  reactor.   When  the  degree  of
saturation desired is achieved (as measured by iodine number) the
reaction is terminated.  Recovered hydrogen is removed  and  sent
back to storage via a booster system.

During  the  hydrogenation  process  a  number  of side reactions
occur, some of  which  cause  significant  waste  water  effluent
contamination.   Isomerization of the double bond along the chain
does  not  cause  any  difficulty.   However,  occasional   chain
scission occurs, resulting in the formation of short chain length
olefins  and  short  chain  fatty acids not desirable in the soap
making process.  As a result of the fatty acid pre-heating  prior
to  hydrogenation  there  is  a tendency for some oxidative cross
linking to occur, resulting in a  modest  amount  of  polymerized
fatty  acids.   Storage  of  the fatty acids at high temperatures
also accelerates this polymerization  reaction.   some  of  these
undesirable reactions result in added waste water contamination.

The  same  raw  waste  loadings can be expected for all levels of
technology.

Raw Waste Loadings - All Levels

The following raw waste loadings are expected:

BOD5 - 1.5 kg/kkg (1.5 lb/1000 Ib) anhydrous acid

COD - 2.5 kg/kkg (2.5 lb/1000 Ib) anhydrous acid

Suspended Solids - 1.0 kg/kkg (1.0 lb/1000 Ib)
                                 124

-------
Fatty Acid
Vapors
(Light Ends)
Barometric
Condenser
                                 Slowdown to
                                 Stream
      FATS RECOVERY SYSTEM

            FIGURE 24
                 125

-------
                   anhydrous acid

Oil and Grease- 1.0 kg/kkg (1.0 lb/1000 Ib)
                anhydrous acid


On a thirty day  average  basis,  the  following  guidelines  are
recommended:

BOD5 - 0.15 kg/kkg (0.15 lb/1000 Ib)  anhydrous acid

COD - 0.25 kg/kkg (0.37 lb/1000 Ib)  anhydrous acid

Suspended Solids - 0.10 kg/kkg  (0.10 lb/1000 Ib)
                   anhydrous acid

Oil and Grease - 0.10 kg/kkg (0.10 lb/1000 Ib)
                 anhydrous acid

pH - 6.0 - 9.0

There is little or no need for an upset allowance in addition to that +-•:
account for variability of treatment.


Rationale and Assumptions

It  may  be  noted that hydrogenation steps in the manufacture of
fatty acids from fats is considered as a  supplemental  allowance
in  view  of  the  occasional  use of this process in the general
manufacturing  system  for  soap  manufacture.    The  levels   of
effluents  suggested  and  their nature have been outlined above,
based upon a reasonable allowance by careful practice of the  art
of hydrogenation and by a careful control and maximum recovery of
effluent streams.  There is no particular discernible addition in
the way of capital requirements or utility and power requirements
that  would  be more than marginal for these effluent limitations
guidelines requirements.

                FATTY ACID NEUTRALIZATION
General

This method of neat soap manufacture is  a  clean  process.   The
major  starting  material, fatty acid, has already been subjected
to a severe refining step.  During the oil splitting process  the
volatile acids and color bodies have been removed.

Neutralization  is  frequently  carried  out with soda ash, which
results  in  the  evolution  of   carbon   dioxide.    In   large
installations,  the  neutralization  may be a continuous process.
Batch operations utilizing stoichiometric amounts of fatty  acids
and alkalis may be employed.
                                  126

-------
Raw Waste Loading


The following raw waste loading can be expected:

BOD5 - 0.1 kg /kkg  (0.1 lb/1000 Ib) anhydrous soap

COD - 0.25 kg /kkg  (0.25 lb/1000 Ib) anhydrous soap

Suspended Solids - 0.2 kg /kkg  (0.2 lb/1000 Ib)
                   anhydrous soap

Oil and Grease - 0.05 kg /kkg  (0.05 lb/1000 Ib)
                 anhydrous soap

B£§£   Practicable   Control   Technology   Currently   Available
Guidelines

On a thirty day average basis the following parameter limits  are
recommended:

BOD5 - 0.01 kg /kkg   (0.01 lb/1000 Ib) anhydrous soap

COD - 0.05 kg/kkg (0.05 lb/1000 Ib) anhydrous soap

Suspended Solids - 0.02 kg /kkg  (0.02 lgs/1000 Ib)
                   anhydrous soap

Oil and Grease - 0.01 kg / kkg  (0.01 lb/1000 Ib)
                 anhydrous soap

pH 6.0 - 9.0

There is little or no need for an additional upset allowance.


Best Practicable control Technology currently Available

Secondary  biological  treatment  will very adequately handle the
effluent from this process.

Rationale, and Assumptions

This process is carried out using  stoichiometric  quantities  of
all  reactants  so that the entire content of the reactor is sent
in  total  to  the  next  processing   step;   bar   soap,   soap
flakes/chips,  or  liquid  soap.    The  product  is  neat soap at
approximately 70 percent concentration.

Leaks from pump and other packing glands should be  gathered  and
returned to the process.

104 - GLYCERINE RECOVERY
                                  127

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General

The  character of the waste water  streams  from glycerine recovery
will be determined by the  source of the  dilute streams which  are
concentrated.   There  are two  sources of  dilute glycerine; one
from the processing of sweet water lyes  of  kettle  boiling  soap
and the other from fat splitting.

In  the case of the soap making source,  a  stream which contains 8
- 15 percent glycerine, salt and miscellaneous organic matter  is
run  to  a  batch evaporator and concentrated  to 60 -  80 percent.
In glycerine concentration the 80  percent  product is removed as a
bottoms product  and  therefore  contains  all  of  the  original
impurities  (less a lot of the original  salt), but in  a much more
concentrated form.  At this point  the  stream is either sold to  a
glycerine  refiner  or  again  batch handled in a glycerine still
where the product is taken overhead.

The dilute glycerine stream from   fat  splitting  can   be  varied
significantly  in concentration.   It all depends upon  how the fat
splitter is operated.  Glycerine is a  bottoms   product  from  the
splitter.  A fairly concentrated glycerine can be obtained if the
yield  of  fatty  acid  is sacrificed  or the production rate is
diminished.

As the glycerine stream  comes  from   the  fat  splitter,  it  is
normally  flashed  to  atmospheric pressure,   thereby gaining an
immediately increased concentration of product.
A simplified flow chart of
process is as follows:
the  concentrating  and  distillation
                                ICondensate to Waste
                                            ^
                              Concentrated
                              Glycerine
                              60 - 807.
              Glycerine
f. 	
Salt filtered
or centrifuged


              To Soap
              Manufacture

                     GLYCERINE CONCENTRATION

                           FIGURE 25
Raw Waste Loading

The  glycerine concentration and glycerine distillation should be
handled  separately.   Quite  often  the   glycerine    which   is
                                  128

-------
concentrated  to  60  or  80  percent is sold to another firm for
further distillation to an assay of 98+ percent glycerine.

Raw waste characteristics are expected to average as follows:

Glycerine Concentration

BOD5 - 15 kg /kkg  (15 lb/1000 Ib) anhydrous glycerine

COD - 30 kg /kkg  (30 lb/1000 Ib) anhydrous glycerine

Suspended Solids - 2 kg /kkg  (2 lb/1000 Ib) anhydrous
                   glycerine

Oil and Grease - 1 kg/kkg (1 lb/1000 Ib) anhydrous
                 glycerine

Glycerine Distillation

BODji - 5 kg /kkg  (5 lb/1000 Ib) anhydrous glycerine

COD - 10 kg /kkg  (10 lb/1000 Ib) anhydrous glycerine

Suspended Solids - 2 kg /kkg  (2 lb/1000 Ib)
                   anhydrous glycerine

Oil and Grease - 1 kg/kkg  (1 lb/1000 Ib) anhydrous glycerine

Best Practicable Control Technology Currently Available Guidelines

Separate guidelines should be established  for  the  waste  water
effluents  for  the  glycerine  concentration  step and the final
glycerine distillation since, in many cases, these two operations
are not carried out at the same geographical location nor by  the
same   manufacturer.    In   the  event  both  concentration  and
distillation are conducted at the same  location,  the  parameter
values  of each operation should be combined for a final effluent
allowance.

On a thirty day average basis, the following effluent  guidelines
are recommended:


Glycerine concentration

BOD5 - 1.50 kg /kkg (1.50 lb/1000 Ib)  anhydrous glycerine

COD - 4.50 kg/1000 Ig (4.50 lb/1000 Ib) anhydrous glycerine

Suspended Solids - 0.20 kg/kkg   (0.20 lb/1000 Ib)
                   anhydrous glycerine

Oil and Grease - 0.10 kg /kkg   (0.10 lb/1000 Ib)  anhydrous
                 glycerine
                                    129

-------
pH  6.0-9.0

Glycerine Distillation

BOD5 - 0.50 kg /kkg (0.50 lb/1000 Ib) anhydrous glycerine

COD - 1.50 kg /kkg (1.50 lb/1000 Ib) anhydrous glycerine

Suspended Solids - 0.20 kg / kkg  (0.20 lb/1000 Ib)
                   anhydrous glycerine

Oil and Grease - 0.10 kg /kkg  (0.10 lb/1000 Ib)  anhydrous
                 glycerine

pH  6.0 - 9.0

Little  or  no  upset  allowance is justifiable and it should not
affect the thirty day average for either glycerine  concentration
or  distillation.   Therefore,  the  allowance for variability of
treatment is sufficient to cover these subcategories.

Best Practicable control Technology Currently Available

Much of the glycerine concentrating equipment in soap  plants  is
fairly  old.  It is operated in a batch manner and apparently the
vapors carry a fair amount of entrainment, as is evidenced by the
amount of salt carryover in the condensate.  The  long  residence
time  in  the  concentrators helps to build up glycerine polymers
and degrades other heavy ends leading to high  BOD5  loadings  in
the resulting waste water stream.

Where  the  barometric  condenser  is  continued  in use, the in-
stallation of a  biological  cooling  tower  with  the  attendant
recycle  of  barometric water can materially reduce the raw waste
load.

Rationale and Assumption

In almost all cases observed there has been  a  significant  BOD5_
loading  in  the  barometric condenser water, which is due to the
glycerine escaping the condensing system.   Apparently this is not
now regarded as a worrisome economic loss; it does  constitute  a
high  biochemical  loading.   The  employment  of  more efficient
condensers, eliminating the barometric leg, is one way  in  which
effluent   loadings  can  be  reduced.   Another  method  is  the
employment of column  reflux  in  the  glycerine  evaporators  to
reduce glycerine loss.

105 - SOAP FLAKES AND POWDERS

General
                                  130

-------
Nea-t  soap  is  either chill roll, air or spray dried.  In either
case, the waste water loading is minimal.  There  are  occasional
washdowns and cleanups required, though rare.

Raw Waste Loading

The  leaks,  spills  and pump gland cooling water will contribute
the following loadings:

BOD5 - 0.1 kg /kkg   (0.1 lb/1000 Ib) anhydrous soap

COD - 0.3 kg /kkg   (0.3 lb/1000 Ib) anhydrous soap

Suspended Solids - 0.1 kg /kkg  (0.1 lb/1000 Ib)
                   anhydrous soap

Oil and Grease - 0.1 kg /kkg  (0.1 lb/1000 Ib)
                 anhydrous soap

Best   Practicable   Control   Technology   Currently   Available
Guidelines

On  a  thirty  day  average  basis, the parameter levels are rec-
ommended to be:

BOD5 - 0.01 kg /kkg  (0.01 lb/1000 Ib) anhydrous soap

COD - 0.05 kg /kkg   (0.05 lb/1000 Ib) anhydrous soap

Suspended Solids - 0.01 kg /kkg  (0.01 lb/1000 Ib) anhydrous soap

Oil and Grease - 0.01 kg /kkg   (0.01 lb/1000 Ib) anhydrous soap

pH  6.0 - 9.0

The permit authority may find an occasional situation meriting  a
spot   increase  above  these  values  for  unforeseen  equipment
washouts in addition to the allowance for treatment variation.

Best Practicable Control Technology Currently Available

Manufacture of flakes and powders  has  been  optimized  well  to
minimize  losses.   The  systems  are  maintained  dry  in normal
practice, thereby no continuous waste water is  generated.   Only
where  there is associated soap reboil (to recover scrap soap) is
there any appreciable amount of effluent generated.

Incineration of scrap soap is one way in which effluents could be
reduced, where applicable  and  economically  feasible.   In  any
event,  biological  secondary treatment will appropriately reduce
the waste loadings to acceptable levels.

106 - BAR SOAPS
                                  131

-------
General

Starting with neat soap (approximately 70 percent  soap  solution
in  water)  the  processes for making bar soaps are quite varied.
The major differences occur in the drying  technique.   Soaps  in
bar  form  will  have  a  final  moisture  content varying from 8
percent  to  over  15  percent,  depending  upon  the  particular
properites desired.

Depending   upon  the  particular  products  made  and  processes
employed, situations encountered range from those with  no  waste
water  effluents  of  any  kind generated to those having several
scrubber water effluents.   Washouts may  be  a  minor  source  of
pollution,  both  in  terms  of  effluent  volume  and  pollutant
loadings.

Raw Waste Loading

The following waste water effluent concentrations are regarded as
an average expectation:

BOD5 - 3.4 kg /kkg   (3.4 lb/1000 Ib) anhydrous soap

COD - 5.7 kg /kkg  (5.7 lb/1000 Ib) anhydrous soap

Suspended Solids - 5.8 kg/kkg  (5.8 lb/1000 Ib) anhydrous soap

Oil and Grease - 0.4 kg/kkg  (o.4 lb/1000 Ib) anhydrous
                 soap.
Best Practicable Control Technology Currently Available Guidelines

On a thirty day average basis the following parameter values  are
recommended:

BOD5 - 0.34 kg/kkg  (0.34 lb/1000 Ib) anhydrous soap

COD - 0.85 kg/kkg  (0.85 lb/1000 Ib) anhydrous soap

Suspended Solids - C.58 kg/kkg  (0.58 lb/1000 Ib)
                   anhydrous soap

Oil and Grease - 0.04 kg/kkg (0.04 lb/1000 Ib)  anhydrous soap

pH  6.0-9.0


Little or no allowance for upset is required.

Best Practicable Control Technology Currently Available
                                  132

-------
There  is  concerted effort within the  industry to minimize water
use  in  this  particular  operation.   One  of  the   unresolved
questions  is  whether  air quality restrictions will force other
"dry" operators to incorporate  scrubber systems  for  picking  up
elusive soap dust.

The  levels specified in the guidelines are readily achievable by
the collection and recycle of soap dust (via dust  collectors  or
scrubbers) or by secondary biological treatment.

Ratjgnale^and Assumptions

Without  much  more  detailed   analysis of  the  bar soap making
operation it is very difficult  to discern  just how close to  zero
discharge all processes could come without seriously jeopardizing
the product performance, hence  the relatively broad allowances.

107 - LIQUID SOAP

general

Neat soap  (approximately 70 percent soap and 30 percent water) is
run  into  a  mixing  tank  to  be blended  with other ingredients,
filtered if required, and drummed.  There  may  be  need  for  an
occasional equipment washout and a frequent filter cleanout.

Constituents going into these blends are quite varied since their
functions range widely.  This kind of business is close to custom
blending  due  to  the  high  performance  nature of many of their
products.

Raw Waste Loading

On the basis of a thirty day  average   the  following  raw  waste
loadings can be expected:

BOD5 - 0.1 kg/kkg (0.1 lb/1000  Ib) anhydrous soap

COD - 0.3 kg/kkg (0.3 lb/1000 Ib) anhydrous soap

Suspended Solids - 0.1 kg/kkg (0.1 lb/1000 Ib)  anhydrous soap

Oil and Grease - 0.1 kg/kkg (0.1 lb/1000 Ib)  anhydrous soap
  §£   Practicable   Control   Technology   Currently   Available
Guidelines           "~

As a thirty day average the following effluent  parameter  values
are recommended:

BOD5 - 0.01 kg/kkg  (0.01 lb/1000 Ib) anhydrous soap

COD - 0.05 kg/kkg (0.05 ;bs/1000 Ib) anhydrous soap
                                 133

-------
Suspended Solids - 0.01 kg/kkg (0.01 lb/1000 Ib)  anhydrous soap

Oil and Grease - 0.01 kg/kkg (0.01 lb/1000 Ib)  anhydrous soap

pH  6.0-9.0

There may be an occasional need on the part of some manufacturers
to  exceed  these  limits  due  to  a  highly  varied product mix
requiring washouts more frequently than allowed above.

Best Practicable Control^Technology Currently Available

Secondary biological treatment is adequate  to  meet  the  levels
proposed.

Rationale and Assumptions

This  processing  step  is essentially clean, requiring only rare
washouts  to  prevent  cross  contamination  of   widely   varied
performance  products.   Many  of these same processors blend dry
detergents  requiring  comparable  frequency  of   washouts.    A
biological  secondary  treatment  is  expected  to be adequate to
handle the effluents.

201 - OLEUM SULFONATION/SULFATION

General

This chemical process has been optimized in that it is close to a
"push button"  operation.   It  is  practically  troublefree  and
requires  washdowns  only  when there is to be maintenance of the
operating equipment.  The  leaking  pump  glands  are  a  problem
typical  of  this  kind  of  equipment,  but  modest  in  nature.
Normally an operator can quickly observe a significant  leak  and
repair it promptly.

Raw Waste Loading

An average expected raw waste loading is:

BOD5 - 0.2 kg/kkg  (0.2 lb/1000 Ib) anhydrous product

COD - 0.6 kg/kkg  (0.6 lb/1000 Ib) anhydrous product

Suspended Solids - 0.3 kg/kkg (0.3 lb/1000 Ib)  anhydrous
                   product

Oil and Grease - 0.3 kg/kkg (0.3 lb/1000 Ib) anhydrous product

Surfactant - 0.7 kg/kkg  (0.7 lb/1000 Ib) anhydrous product

Best   Practicable   control   Technology   Currently   Available
Guidelines
                                   134

-------
The following thirty day  average  recommendations  for  effluent
loadings  are  made with the understanding that there may be some
firms  on  some  occasions  requiring  additional  loadings   for
washouts  of  equipment.   Further, during any 24 hour period the
limits could be allowed to slightly exceed 3 times the average as
long as the thirty day average meets the guidelines.   This  will
account for both variability of operation and treatment.

BOD5 - 0.02 kg/kkg (0.02 lb/1000 Ib) anhydrous product


COD - 0.09 kg/kkg  (0.09 lb/10CO Ib) anhydrous product

Suspended Solids - 0.03 kg/kkg  (0.03 lb/1000 Ib) anhydrous
                   product

Oil and Grease - 0.03 kg/kkg  (0.03 lb/1000 Ib) anhydrous product

Surfactant - 0.07 kg/kkg (0.07 lb/1000 Ib) anhydrous product

pH  6.0 - 9.0

Some  small scale batch operated plants may have great difficulty
in reaching these levels.  Consideration should be given  by  the
permit  writing  authority  for modest relaxation of these levels
where circumstances clearly warrant them.

Best Practicable Control Technology Currently Available

As indicated in  the  general  discussion  this  process  can  be
operated  continuously  in  essentially  a  trouble-free  manner.
There is little room for improvement.

Other than the gland leakage and very  occasional  washouts  this
process  has  no effluent.   Gland leakage around pump shafts is a
universal problem  wherever  liquids  are  handled,  particularly
corrosive liquids.  Because of the corrosive nature of the oleum,
thorough  washouts  are mandatory prior to maintenance work being
carried out on the equipment.

Integrated plants will have little difficulty meeting the  levels
of  the  guidelines.   The washwater can be recycled and the leaks
and spills run to the neutralization unit.

Biological secondary treatment will handle  the  residual  wastes
when they occur.

202 - AIR-S03 SULFATION/SULFONATION

General

This  process  is  in  as widespread use as the oleum sulfonation
(201), particularly for the sulfation  of  alcohols  and  ethoxy-
lates.   Although continuous and automatic, the Air - S03 process
                                  135

-------
is much more inclined to cause product degradation than the oleum
unit.

Whenever  the  process  is  started  up  some  material  must  be
discarded  due  to  low  sulfonation  making  the  material below
specification.  Promptly upon shutdown  a  thorough  washdown  is
required  to  keep  char  formation to a minimum.  There are mist
knockdown scrubbers which will also  contribute  to  waste  water
loadings.

Raw Waste Loading

Average expected raw waste loadings are:

BOD5 - 3 kg/kkg (3 lb/1000 Ib) anhydrous product

COD -  9 kg/kkg (9 lb/1000 Ib) anhydrous product

Suspended Solids - 0.3 kg/kkg (0.3 lb/1000 Ib)
                   anhydrous product

Surfactant - 3 kg/kkg (3 lb/1000 Ib)  anhydrous
             product

Oil and Grease - 0.5 kg/kkg (0.5 lb/1000 Ib)
                 anhydrous product
       Practicable   Cgntrpl   Technology   Currently
Guidelines

Thirty day average recommendations are made on a similar basis as
those for  Subcategory  201  -  Oleum  Sulfonation.   Because  of
product changes or mechanical failures some plants may, at times,
have  to exceed established effluent limits.  Such cases have not
been provided for in suggested guidelines.  Therefore, regulatory
agencies may wish to extend special consideration in  such  cases
and write appropriate limitations into any permits they issue.

BOD5 - 0.30 kg/kkg (0.30 lb/1000 Ib)  anhydrous product

COD - 1.35 kg/kkg (1.35 lb/1000 Ib) anhydrous product

Suspended Solids - 0.03 kg/kkg (0.03 lb/1000 Ib)
                   anhydrous product

Surfactant - 0.30 kg/kkg (0.30 lb/1000 Ib) anhydrous
             product

Oil and Grease - 0.05 kg/kkg (0.05 lb/1000 Ib) anhydrous
                 product

pH 6.0 - 9.0
                                    136

-------
Best Practicable control Technology Current.lv Available

This  process  -too  has  received  much  research and development
attention leaving little to be expected in the short term in  the
form of process improvement.

In-plant  practices  can  significantly aid in reducing raw waste
loads by handling much of the cleanup dry, or  blending  off  the
material   into   industrial   cleaners,  provided  the  firm  is
sufficiently integrated.

Rationale and Assumptions

In small plants particularly, there must  be  accommodation  made
for  the disposal of these rather minimal wastes, in that the off
specification product could seriously impact the product  quality
if incorporated in that stream.

The  raw  waste  loading has been structured higher than that for
oleum sulfonation to acknowledge the  product  degradation  which
takes  place  when  sulfonated  material  remains in the reaction
area, requiring thorough washouts.

203 - SQ3 SOLVENT ANP_yA.CUUM.SULFONATION

General

Other than an occasional washout,  this  process  is  essentially
free of waste water generation.

Raw Waste Loading

The following raw waste loading is expected:

BOD5 - 3 kg/kkg (3 lb/1000 Ib) anhydrous product

COD - 9 kg/kkg (9 lb/1000 Ib) anhydrous product

Suspended Solids - 0.3 kg/kkg  (0.30 lb/1000 Ib)
                   anhydrous product

Surfactant - 3 kg/kkg (3 lb/1000 Ib) anhydrous
             product

Oil and Grease - 0.5 kg/kkg  (0.5 lb/1000 Ib) anhydrous
                 product


Best^ Practicable Control._Technology Currently Available Guidelines

On a thirty day average basis, the following parameter levels are
recommended:

BOD5 - 0.30 kg/kkg (0.30 lb/1000 Ib) anhydrous product
                                  137

-------
COD - 1.35 kg/kkg  (1.35 lb/1000 Ib) anhydrous product

Suspended Solids - 0.03 kg/kkg  (0.03 lb/1000 Ib)
                   anhydrous product

Surfactant - 0.30 kg/kkg  (0.30 lbs/1000 Ibs) anhydrous
             product

Oil and Grease - 0.05 kg/kkg (0.05 lb/1000 Ib) anhydrous
                 product

pH  6.0 - 9.0

No additional allowance above that for variability of treatment need be
made for startup, shutdown
or upset conditions.

Best^Practicable Control Technology Currently Available

Secondary biological treatment will adequately handle the
wastes from this process.

Rationale

As in other categories, there will be some occasions when
washouts will be required.

20t - SULFAMIC^ACID SULFATION

General

Washouts are the only waste water effluents from this pro-
cess.


Raw Waste Loading

The following raw waste loading is expected:

BOD5 - 3 kg/kkg  (3 lb/1000 Ib)  anhydrous product

COD - 9 kg/kkg (9 lb/1000 Ib) anhydrous product

Suspended Solids - 0.3 kg/kkg (0.3 lb/1000 Ib)
                   anhydrous product

Surfactant - 3 kg/kkg  (3 lb/1000 Ib) anhydrous
             product

Oil and Grease - 0.5 kg/kkg  (0.5 lb/1000 Ib) anhy-
                 drous product
                                  138

-------
Best   Practicable   Control   Technology   Currently   Available
Guidelines                                  "

On a thirty day average basis, the following parameter levels are
recommended:

BOD5 - 0.3 kg/kkg  (0.3 lb/1000 Ib) anhydrous pro-
   ~~   duct

COD - 1.35 kg/kkg  (1.35 lb/1000 Ib) anhydrous product

Suspended Solids - 0.03 kg/kkg (0.03 lb/1000 ib)
                   anhydrous product

Surfactant - 0.3 kg/kkg (0.3 lb/1000 Ib) anhydrous
             product

Oil and Grease - 0.05 kg/kkg (0.05 lb/1000 Ib) anhy-
                 drous product

pH  6.0-9.0

No startup, shutdown or upset allowance is recommended.

Best Practicable Control Technology Currently Available

In order to comply with these guidelines the  operator  would  be
obliged to recycle the most wash water rather than sewer it.

Rationale

This  reaction  is  normally  carried out in batches.  Reasonable
housekeeping would permit the recycle via a holding tank for most
of the washwater.  As in other processes,  this  one  can  either
accumulate  unusable  amounts of dilute washwater or occasionally
have off-specification material to  be  disposed  of.   Unlike  a
large  integrated  plant, the.firm using this process is unlikely
to have any alternative other than disposal.

205 - CHLOROSULFONIC ACID SULFATION

General

This specialized process is  another  route  to  a  high  quality
surfactant produced uniquely under mild reaction conditions.  The
by-product   HCl   is   a   significant  distinction  from  other
sulfcnation processes.  It is usually scrubbed out in  a  caustic
solution  with  the  formation  of salt or dissolved in water for
sale as muriatic acid.

Raw Waste Loading

The following values can be expected on a thirty day basis:
                                 139

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BOD5 - 3 kg/kkg (3 lb/1000 Ib) anhydrous product

COD - 9 kg/kkg (9 lb/1000 Ib) anhydrous product

Suspended Solids - 0.3 kg/kkg (0.3 lb/1000 Ib)
                   anhydrous product

Surfactant - 3 kg/kkg  (3 lb/1000 Ib) anhydrous pro-
             duct

Oil and Grease - 0.5 kg/kkg  (0.5 lb/1000 Ib) anhydrous
                 product

Best Practicable Control Technology Currently Available Guidelines

As a thirty day average the following parameter levels are
recommended:

BOD5 - 0.3 kg/kkg (0.3 lb/1000 Ib) anhydrous product

COD - 1.35 kg/kkg (1.35 lb/1000 Ib) anhydrous product

Suspended Solids - 0.03 kg/kkg (0.03 lb/1000 Ib)
                   anhydrous product

Surfactant - 0.30 kg/kkg (0.30 lb/1000 Ib) anhydrous
             product

Oil and Grease - 0.05 kg/kkg  (0.05 lb/1000 Ib) anhy-
                 drous product

pH  6.0 - 9.0

No upsets, startup or shutdown allowances are recommended.

Best mPracticable Control TechnologY^Currently Available

This important, moderately  used  process  is  optimized  to  the
extent reasonably expected.
The  effluent  washouts  are  minimal  and  the required loadings
reasonable in relationship to  the  other  processes.   Recycling
washouts   can   materially  aid  in  meeting  these  guidelines.
Biological secondary treatment is adequate to handle the expected
raw waste load.

206 - NEUTRALIZATION OF SULFURIC ACID ESTERS AND SULFQNIC ACIDS

General

Neutralization is the essential step which converts the  sulfonic
acids  or sulfuric acid esters into neutral surfactants.  It  is  a
                                 140

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potential source of some oil and grease  generation  due  to  the
possible hydrolysis of the sulfates.  Occasional leaks and spills
around  the  pump,  valves, etc., are the only expected source of
waste water contamination.

Raw Waste Loading

The following loadings can be expected:

BOD§ - 0.10 kg/kkg  (0.10 lb/1000 lb) anhydrous product

COD - 0.3 kg/kkg  (0.3 lb/1000 lb) anhydrous product

Suspended Solids - 0.3 kg/kkg (0.3 lb/1000 lb) anhy-
                   drous product

Surfactant - 0.2 kg/kkg  (0.2 lb/1000 lb) anhydrous
             product

Oil and Grease - 0.1 kg/kkg (0.1 lb/1000 lb) anhydrous
                 product

Best_Practicable Control Technology Currently Available Guidelines

On a thirty day average basis the following parameter values  are
recommended:

BOD5 - 0.01 kg/kkg  (0.01 lb/1000 lb) anhydrous product

COD - 0.05 kg/kkg  (0.05 lb/1000 lb) anhydrous product

Suspended Solids - 0.03 kg/kkg  (0.03 lb/1000 lb) anhy-
                   drous product

Surfactant - 0.02 kg/kkg (0.02 lb/1000 lb) anhydrous
             product

Oil and Grease - 0.01 kg/kkg (0.01 lb/1000 lb) anhydrous
                 product

pH  6.0 - 9.0

No startup, shutdown or upset allowances are recommended.

Best Practicable Control Technology Currently Available

This  process step is quite simple and usually continuous when in
tandem with a continuous sulfonator.  The biotreater in secondary
treatment  processing  can  accommodate  the  load.   Recycle  is
probably the best way to eliminate waste loads.

Rationale
                                141

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In a large volume operation of this type there will be occasional
inadvertent  leaks  of  valve  and  pump  packing,  spills due to
maintenance disruption  of  piping,  and  occasional  cleanup  to
repair  the equipment, all necessitating the generation of dilute
waste water streams.  These streams are usually  too  dilute  for
recycle  back  into  the  process, but by use of small amounts of
water, recyle is practical.  By storage and recycle some of  this
washout  water  could  diminish  the  problem and lead to product
recovery later in the finishing process.

207 — SPRAY DRIED DETERGENTS

General

This unit operation is one of the most critical - and the largest
- as well as the most important of the detergent industry.  Here,
the final detergent particles are  formed  which  must  have  the
appropriate  physical  characteristics  for solubility, packaging
and storage.

Tower cleanliness is essential so that  degradation  products  or
material  significantly  different  made in an earlier run do not
contaminate the currently processed product.  In such a case, the
spray tower is  put  through  a  multi-stage,  thorough  cleaning
process.

After  the  large  dry "chunks" of adhering detergent are knocked
down by hand, the tower walls are  abraded.   Finally,  water  is
played  over  the  surface  to  finish the cleaning process.  The
frequency of tower "turnaround" varies considerably in  practice.
Some  towers  operate for many weeks before shutdown and washing.
Others may have a tower  changeover  sixteen  times  in  a  given
month.   In  many cases there are product changeovers made on-the-
fly requiring neither  stoppage  of  spray  tower  operation  nor
cleanout.

Among many of the towers which have extended runs on one product,
there  is  minimal discharge as waste water effluent.  All of the
dry product is recycled or sent to  solid  waste  disposal.   The
washwater  and  scrubber  water is all sent back into the process
and recycled to extinction.

There  are  numerous  possible  sources   of   water   containing
contaminants   originating   in  this  process.   They  encompass
crutcher cleanouts, packaging equipment cleanouts,  storage  area
washouts, vent scrubbers, etc.

Characteristics of the exit air coming out of the spray tower are
largely   determined   by   the   composition  of  the  detergent
formulation being dried.  The increasing use of alcohol  sulfates
and  ethoxylated  alcohols  as  active  ingredients has increased
plume generation in this air  stream  which  is  not  effectively
eliminated   by   mechanical   and  electrostatic  methods,  thus
                                  142

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resulting  in  a  significant  volume  of  scrubber  water  being
employed.

The total volume of scrubber water and washouts becomes too great
to  te recycled to extinction in some spray tower operations when
they have to meet source air standards.  Consequently, some waste
water is expected to be sent to the sewer under these conditions.

A similar problem is faced by those who operate spray towers on a
fast turnaround basis.  They end up with much more washout  waste
water than they can handle via recycle.

In  both  cases  cited  above, the other immediately apparent al-
ternative is to reuse  all  of  the  water,  forcing  the  solids
concentration  of the tower slurry from around 70 percent to some
lower value.  This is not a  suitable  alternative,  particularly
from   an   environmental   viewpoint,   since  excessive  energy
consumption would be required to drive off the additional water.

Raw Haste Loading

Under normal spray tower operation,  a  thirty  day  average  raw
waste loading can be expected to reach:

BOD5 - 0.1 kg/kkg (0.1 lb/1000 Ib)  anhydrous product

COD - 0.3 kg/kkg (0.3 lb/1000 Ib) anhydrous product

Suspended Solids - 0.1 kg/kkg (0.1 lb/1000 Ib) anhy-
                   drous product

Surfactant - 0.2 kg/kkg (0.2 lb/1000 Ib) anhydrous product

In towers facing particularly stringent air quality problems, the
following waste water loadings can be expected:

BOD5. - 0.8 kg/kkg (0.8 lb/1000 Ib)  anhydrous product
COD~- 2.5 kg/kkg (2.5 lb/1000 Ib) anhydrous product

Suspended solids - 1.0 kg/kkg (1.0 lb/1000 Ib) anhy-
                   drous product

Surfactant - 1.5 kg/kkg (1.5 lb/1000 Ib) anhydrous
             product

Oil and Grease - 0.3 kg/kkg (0.3 lb/1000 Ib)  anhydrous
                 product


In  spray towers having fast turnarounds (more than 6 per month),
for each added turnaround, the following additional  waste  water
loadings can be expected:

BOD5 - 2.0 kg/kkg (2.0 lb/1000 Ib)  anhydrous product
                                  143

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COD - 6.0 kg/kkg  (6.0 lb/1000 Ib) anhydrous product

Suspended Solids - 2.0 kg/kkg (2.0 lb/1000 Ib) anhydrous
                   product

Surfactant - 4.0 kg/kkg  (1.0 lb/1000 Ib) anhydrous
             product

Oil and Grease - 0.3 kg/kkg  (0.3 lb/1000 Ib) anhydrous
                 product

Best_Practicable Control Technology Currently Available Guidelines

For normal spray tower operation the following thirty day average
parameter values are recommended:

BOD5 - 0.01 kg/kkg (0.01 lb/1000 Ib) anhydrous product

COD - 0.05 kg/kkg  (0.05 lb/1000 Ib) anhydrous product

Suspended Solids - 0.01 kg/kkg  (0.01 lb/1000 Ib) anhy-
                   drous product

Surfactant - 0.02 kg/kkg (0.02 lb/1000 Ib) anhydrous
             product

pH - 6.0 - 9.0

No special startup, shutdown or upset allowances are recommended.

For  spray towers operating under stringent air quality problems,
the   thirty   day   average    parameter    loading    guideline
recommendations are:

BOD5 - 0.08 kg /kkg  (0.08 lb/1000 Ib) anhydrous product

COD - 0.37 kg /kkg  (0.37 lb/1000 Ib) anhydrous product

Suspended Solids - 0.10 kg /kkg  (0.10 lb/1000 Ib) an-
                   hydrous product

Surfactant - 0.15 kg/kkg (0.15 lb/1000 Ib) anhydrous
             product

Oil and Grease - 0.03 kg/kkg  (0.03 lb/1000 Ib) anhy-
                 drous product

pH - 6.0 - 9.0

For  spray  tower  operation  with fast turnaround, the following
additional allowance should be made for each turnaround  above   6
per month:

BOD5 - 0.02 kg/kkg  (0.02 lb/1000 Ib) anhydrous product



                                 144

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COD - 0.09 kg/kkg   (0.09 lb/1000 Ib) anhydrous product

Suspended Solids - 0.02 kg/kkg   (0.02 lb/1000 Ib) an-
                   hydrous product

Surfactant - 0.04 kg/kkg   (O.OU lb/1000 Ib) anhydrous
             product

Oil and Grease - no additional allowance

pH - 6.0 - 9.0

This is in essence an upset allowance for shutdown and startup.

No other special upset allowances are recommended for spray tower
operations in general.

Best Practicable_Control Technology Currently Available

It  is  expected  that the levels of effluent constituents can be
met readily if the  equivalent  of  cyclone  scrubbers  are  used
before electrostatic precipitators in the air stream exiting from
the spray tower.  Since the function of the water scrubbing is to
chill the air as well as remove particulate matter, a significant
step toward reduced effluent loading can be taken by substituting
cooled recycle water for that used on a once through basis.

With  the water recycled, a sufficient concentration can be built
up in the water flow to  make  return  to  the  detergent  making
process   possible.    Foaming  is  avoided  by  maintaining  the
surfactant concentration at a  sufficiently  high  level  in  the
recycled  scrubber water.  Though only a possible option for best
practicable  technology,  this  approach  should   be   seriously
considered for best available technology.

Ultimately,  the  secondary  biotreater  will  have no difficulty
processing the waste load from the spray tower area.

Rationale

The demands for clean air and clean water come into  conflict  in
spray tower operation.  In order to meet the increasingly tighter
air pollution regulations while producing products which are more
environmentally  compatible,  tower  operation  problems develop.
These newer formulations contain increasing amounts  of  nonionic
surfactants  which  are  prone  to  produce an aerosol plume that
persists in the exit tower gas.

A  system  of  dry  cyclone  dust  collectors  followed   by   an
electrostatic   precipitator   is   suitable   for  removing  the
particulate matter present, but it does not influence  the  plume
since it is a vapor.
                                 145

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By inserting a wet scrubber in between the cyclone dust collector
and  the  electrostatic  precipitator  the  particulate matter is
further reduced and the organic aerosol vapors are  condensed  so
that they can then be removed by the electrostatic precipitator.

Introduction of this scrubber water flow now converts a potential
air   contamination  into  a  waste  water  problem.   Since  the
materials  removed  in  the  scrubber   are   biodegradable   and
essentially  the  same  product  as  that  which  is put into our
sanitary sewers throughout the country, this  is  a  satisfactory
method of minimizing the environmental impact.

Additional  study is needed in this area, particularly concerning
the economics of installing sufficient tankage to enable the fast
turnaround towers to approach total recycle.

208 — LIQUID DETERGENT MANUFACTURE

General

There are numerous liquid  detergent  products  made  and  it  is
likely  that  they  are  going  to  become  more abundant as more
emphasis is placed upon nonphosphate  products.   Many  products,
including  heavy-duty detergents, are more amenable to convenient
use and manufacture in the liquid form than as a dry powder.

The  term  "liquid  detergents"  embraces  a  large  variety   of
formulations  which  fulfill  an  equally large spectrum of uses.
The ingredients used  to  formulate  the  products  have  a  wide
response  to  such tests as BOD5.  Consequently, the statement of
any single raw waste loading could cause a significant problem to
a given manufacturer.

In the process of preparing the liquid detergent, there  are  two
main  sources  of  waste  water  effluent,  mixing  equipment and
distribution system washouts and filling equipment cleanup.  Most
operators recycle as much diluted product as possible, but, as in
the case of spray tower operation, the total water volume  cannot
be economically recycled to extinction.

Raw Waste Loading

On  a  thirty day average basis, the following raw waste loadings
will be experienced:

BOD5 - 2 kg/kkg (2 lb/1000 Ib)  anhydrous product

COD - 4 kg/kkg (U lb/1000 Ib)  anhydrous product

Surfactant - 1.3 kg/kkg (1.3 lb/1000 Ib) anhydrous product

However, when observing smaller firms, the raw waste loadings may
get to:
                              146

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BOD5 - 5 kg/kkg  (5 lb/1000 Ib) anhydrous product

COD - 7 kg/kkg   (7 lb/1000 Ib) anhydrous product

Surfactant - 3.3 kg/kkg   (3.3 lb/1000 Ib) anhydrous
             product

This latter case is  associated  with  the  high  use  of  common
transfer  lines  for  moving the product to filling lines, losses
resulting from breaking hose  connections  and  relatively  short
filling runs.

Best Practicable Control Technology Currently Available Guidelines

On a thirty day average basis, the following parameter levels are
recommended:

BOD5 - 0.2 kg/kkg  (0.2 lb/1000 Ib) anhydrous product

COD - 0.6 kg/kkg   (0.6 lb/1000 Ib)  anhydrous product

Surfactant - 0.13 kg/kkg   (0.13 lb/1000 Ib)  anhy-
             drous product
pH - 6.0 - 9.0

There should be some accommodations made for the smaller operator
where  his  loadings  are  marginally  greater  than those shown.
Basically, this accommodation should  be  in  the  nature  of  an
allowance  for  the  number of product changes requiring complete
purging and cleaning of filling lines.  Another  exception  which
should  be  noted  is  that the COD/BOD^ ratio may rise to 5:1 or
more due to  the  use  of  some  relatively  bio-hard  industrial
cleaner  ingredients  such  as orthodichlorobenzene, hydrochloric
acid, or chromic acid,  such compounds can  upset  the  biota  in
BOD5 tests, as well as giving a refractory residue.  No allowance
need be made for the suspended solids or oil and grease since the
products  marketed are normally clear, filtered fluids, devoid of
suspended particles.

Best Practicable Control Technology Currently Available

Secondary biological treatment will adequately handle  the  waste
water  effluents  from  this  process if good in-plant control is
practiced to limit the amount of refractory materials.

Rationale

With an industry very much aware of market demands, there will be
a continually changing array of formulations to meet new consumer
preferences and environmental  performance  demands.   There  are
generally  two different markets for liquid detergents; household
and industrial.  In this latter  market,  many  moderately  sized
operators  supply a wide variety of special purpose detergents to
                              147

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meet very specialized needs.  Often fairly "exotic" materials are
used.

Relatively  small  operators  do  not  have  the  flexibility  of
operation   of  the  large  manufacturers.   This,  coupled  with
numerous small batches of product, creates  special  waste  water
problems,  since  there  is no place to hold or recycle numerous,
varied spills, leaks and washouts associated with  the  automated
filling lines.  The cut-off point in allowances becomes critical,
then,  since  it could have severe economic consequences for some
manufacturers.  There are  other  special  problems  relating  to
analytical  results  of  effluent  evaluations.   Due to the wide
variety of products used in liquid formulations, fully acclimated
cultures may not be available for gaining results  which  reflect
the actual technical conditions.

209 - DRY DETERGENT BLENDING

General

Many  different  dry detergent blends are made for a multiplicity
of industrial uses.  The product is usually marketed in drums.

The customary practice is for many successive batches to be  made
in a given mixer before a wet washdown is required.

Raw Waste Loading

An average thirty day waste water loading would be:

BOD5 - 0.1 kg/kkg  (0.1 lb/1000 Ib) anhydrous pro-
   ~~   duct

Suspended Solids - 0.1 kg/kkg (0.1 lb/1000 Ibs) anhydrous product


COD - 0.5 kg/kkg   (0.5 lb/1000 Ib) anhydrous product

Surfactant - 0.1 kg/kkg  (0.1 lb/1000 Ib) anhydrous product

Best Practicable Control^Technology Currently^Available Guidelines

Based upon a thirty day average, the recommendations of parameter
loadings are:

BOD5 - 0.01 kg/kkg  (0,01 lb/1000 Ib) anhydrous pro-
       duct

COD - 0.08 kg/kkg  (0.08 lb/1000 Ib) anhydrous pro-
      duct

Suspended Solids - 0.01 kg/kkg   (0.01 lb/1000 Ib)
                   anhydrous product
                                   148

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Surfactant - 0.01 kg/kkg   (0.01 lb/1000 Ib) anhy-
             drous product

pH - 6.0 - 9.0

No  additional  allowance  need be made for startup, shutdown, or
upsets.

Best Practicable Control Technology Currently Available

Biological secondary  treatment  is  adequate  for  the  effluent
involved.

Rationale

A  wide variety of materials are formulated dry.  Although little
water is used, that which is required for the infrequent washings
is critical.  It will be very  dilute  and  diverse  in  content,
unsuitable for recycling.

210 - DRUM DRIED DETERGENTS

General

This  well  established  process  produces  no effluent, but some
provision must be made for those periods  of  mandatory  washdown
due to equipment failure or critical formulation change.


Raw Waste Loading

The average raw waste load which could be expected is:

BOD5 - 0.1 kg/kkg  (0.1 lb/1000 Ib) anhydrous pro-
       duct

COD - 0.3 kg/kkg  (0.3 lb/1000 Ib)  anhydrous pro-
      duct

Suspended Solids - 0.1 kg/kkg  (0.1 lb/1000 Ib)  anhy-
                   drous product

Surfactant - 0.1 kg/kkg  (0.1 lb/1000 Ib)  anhy-
             drous product

Oil and Grease - 0.1 kg/kkg  (0.1 lb/1000 Ib)  an-
                   hydrous product

Best Practicable Control Technology Currently Available Guidelines

On a thirty day average basis, the following parameter levels are
recommended:

BOD5 - 0.01 kg/kkg  (0.01 lb/1000 Ib)  anhydrous



                                   149

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       product

COD - 0.05 kg/kkg   (0.05 lb/1000 Ib) anhydrous
      product

Suspended Solids - 0.01 kg/kkg  (0.01 lb/1000 Ib)
                   anhydrous product

Surfactant - 0.01 kg/kkg  (0.01 lb/1000 Ib) anhy-
             drous product

Oil and Grease - 0.01 kg/kkg   (0.01 lb/1000 Ib)  an-
                 hydrous product

pH - 6.0 - 9.0

No  startup,  shutdown  or upset allowances are required.  Due to
the low values recommended, a total of three  times  the  average
should  be  allowed over any 2H hour period as long as during any
thirty day period the guidelines are maintained.

Best Practicable_Control Technology Currently Available

secondary  biological  treatment  can   adequately   handle   the
constituents.

Rationale

Even  though  the process is essentially dry, the slurry pans and
other equipment will require  an  infrequent  but  necessary  and
thorough washout.

211 - DETERGENT BARS AND_CAKES

General

In the manufacture of detergent bars there is need for meticulous
cleaning  of  equipment to insure that any product which may have
been degraded due to adhering to hot process equipment is removed
and disposed of.

The approximately 160 million pounds of synthetic toilet bar soap
used in the U.S. is significant, yet modest when compared to  the
600 million pounds of "natural" soap used in toilet bars.

Raw Waste Loading

The following raw waste load can be expected:

BOD5 - 7 kg/kkg   (7 lb/1000 Ib) anhydrous product

COD - 22 kg/kkg   (22 lb/1000 Ib) anhydrous product

Suspended Solids - 2 kg/kkg  (2 lb/1000 Ib) anhy-
                                   150

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                   drous product

Surfactant - 5 kg/kkg  (5 lb/1000 Ib) anhydrous
             product

Oil and Grease - 0.2 kg/kkg   (0.2 lb/1000 Ib) anhy-
                 drous product

Best Practicable control Technology Currently Available Guidelines
On  the  basis  of  a thirty day average, the following parameter
levels are recommended:

BOD5 - 0.7 kg/kkg   (0.7 lb/1000 Ib) anhydrous pro-
       duct

COD - 3.3 kg/kkg (3.3 lb/1000 Ib) anhydrous product


Suspended Solids - 0.2 kg/kkg   (0.2 lb/1000 Ib) an-
                   hydrous product

Oil and Grease - 0.02 kg/kkg  (0.02 lb/1000 Ib) an-
                 hydrous product

pH - 6 - 9

No additional allowance is recommended for startup,  shutdown  or
upsets.  During any thirty day period an allowance of three times
the  average  should be allowed over a 24 hour duration, provided
that throughout the entire  thirty  day  period  the  thirty  day
average is not exceeded.
                                    151

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                            SECTION X

        BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE

Introduction

Best  available technology economically achievable is expected to
involve both improvement in the manufacturing process as well  as
adoption  of  the  best  available  treatment  technology that is
within reason economically.

Not all of the processes identified in best  practicable  control
technology  currently  available  are  expected to discharge less
effluent by 1983.  Several of these processes will  have  reached
an  optimum  raw  effluent  reduction in compliance with the best
practicable control  technology  currently  available,  attaining
pollution  levels so low that it is not feasible to reflect minor
improvements in reduced guideline values.  Only those  which  are
expected  to  attain  a  significantly  lower  effluent level are
discussed in detail in this section.

Improved  end-of-pipe  treatment  is  anticipated   for   further
reduction  of both the level of waste discharge and the variation
of treatment efficiency from one day to the next.  In recognition
of the latter, it is recommended  that  the  maximum  single  day
values  not  be more than two times the thirty day averages.  For
those plants having treatment facilities that  attain  discharges
consistent   with   the   limitations   applicable  to  the  best
practicable control, addition of sand or mixed  media  filtration
should  be  considered.   Plants with no treatment facilities, or
grossly  inadequate  facilities,  should   consider   two   stage
activated sludge, with one stage of the plug flow type, as a more
cost  effective  alternative  to  equalization  and  single stage
activated sludge.


                            TABLE 7-1

Best Available Technology Economically Achievable Guidelines Reflecting
No Change From Best Practicable Control Technology Currently Available

Note:  All values are reported as thirty day averages  in  kg/kkg
(lb/1000  Ib)  of anhydrous product made in that subcategory.  The
pH for all subcategories is the range of 6.0 - 9.0.

                        BOD5   COD       Suspended                 Oil &
                                          Solids    surfactant     Grease

Fatty Acid by Fat
Splitting-Hydrogenation
Allowance Only          0.25   0.20        0.20        0.00         0.15

Soap From Fatty Acid
Neutralization          0.01   0.05        0.02        0.00         0.01
                                  153

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Soap Flakes and
Powders                 0.01   0.05        0.01        0.00         C.C1

Liquid Soaps            0.01   0.05        0.01        0.00         0.01

Oleum Sulfonation/
Sulfation               0.02   0.09        0.03        0.03         0.07

S03 Solvent and
Vacuum Sulfonation      0.10   O.U5        0.01        0.10         0.02

Neutralization of
Acids                   0.01   0.05        0.03        0.02         0.01

Detergent Dry
Blending                0.01   0.08        0.01        0.01         0.005

Drum Dried
Detergents              0.01   0.05        0.01        0.01         0.01
                            TABLE 7-2

Best Available Technology Economically Achievable Guidelines Reflecting
Changes From Best Practicable Control Technology Currently Available

Note:  All values are reported as thirty day averages  in  kg/kkg
(lb/1000  Ib)  of anhydrous product made in that subcategory.  The
pH for all subcategories is the range of 6.0 - 9.0.
Batch Kettle Soap

Fatty Acid by
Fat Splitting

Glycerine Concentration 0.40

Glycerine Distillation  0.30

Bar Soaps

Air-SO3 Sulfation/
Sulfonation

Sulfamic Acid
Sulfation

Chlorosulfonic
Acid Sulfation
BOD5
0.40
0.25
0.40
0.30
0.20
0.19
0.10
0.15
COD
1.05
0.90
1.20
0.90
0.60
0.60
O.l»5
0.75
Suspended
.Solids
0.40
0.20
0.10
0.04
0.34
0.02
0.01
0.02
Surfactant
0.0
0.0
0.0
0.0
0.0
0.18
0.10
0.15
Oil 6
Grease
0.05
0.15
0.04
0.02
0.01
0.04
0.02
0.03
                                  154

-------
Spray Dried
Detergents
   Normal               0.01   0.08        0.01         O.C2        O.C05
   Air Quality
       Restricted       0.08   0.35        0.10         0.15        O.C3
   Fast
       Turnaround       0.02   0.09        0.02         0.03        0.005

Liquid Detergents       0.05   0.23        0.005        0.05        C.OC5

Detergent Bars
and Cakes               0.30   1.35        0.10         0.20        0.02


101 - MODIFIED SOAP MANUFACTURE BY BATCH KETTLE

Best Available Technology Economically Achievable and Rationale

A significant reduction of waste water contamination  volume  can
be  made  in  the  fat  pretreatment  step of kettle boiling soap
manufacture by replacing the barometric condenser used in  vacuum
bleaching  by  a surface condenser.  Such replacement would allow
removal of volatile low molecular weight  undesirables  from  the
effluent.  These can be destroyed by burning or perhaps recovered
for  sale  by  refining.   This change is shown in Figure 26.  An
alternative  approach  for  elimination  of  the  pollutant  load
entrained  in  barometric  condensates  is  use  of a liquid film
extraction unit ahead of the barometric  condenser  as  currently
practiced by one company within the industry.

Raw Waste Loading

The expected raw waste load is:

BOD5 - U kg/kkg  (« lb/1000 Ib) anhydrous soap

COD - 7 kg/kkg  (7 lb/1000 Ib) anhydrous soap

Suspended Solids - H kg/kkg   (<* lb/1000 Ib) anhy-
                   drous soap

Oil and Grease - 0.5 kg/kkg   (0.5 lb/1000 Ib) an-
                 hydrous soap

Best Available Technology Economically Achievable Guidelines

Please refer to guidelines in Table 7-2 at beginning of this Section.

102 - FATTY ACID MANUFACTURE BY FAT SPLITTING

Best Available Technology Economically Achievable and Rationale

Referring  to  the schematic flow diagram 102, there are two ways
of diminishing further the effluent streams from this unit.   The


                                  155

-------
                                                          SECTION X
                                                    LEVEL II TECHNOLOGY
                                                        •


                                      101 - SOAP MANUFACTURE BY BATCH KETTLE : MODIFIED
Wll DECEIVING
   STORAGE-TRANSFER
101! FAT REFINING
   AND BLEACHING
                                                                                                                    1013 SOAP BOILING
                                                                                                                                  NEAT SOAP TO
                                                                                                                                     BUNG
                                                                                                                                  AND SALE

                                                                                                                                  GLYCERINE TO
                                                                                                                                  RECOVERY

                                                                                                                                  LOM GRADE SOAP
                                                                                                                                  LOW GRADE
                                                                                                                                   Arrv ACID
                                                        FIGURE   26

-------
                                        SECTION X and SECTION XI
                                         LEVEL II TECHNOLOGY
                                                 and
                                         LEVEL III TECHNOLOGY

                         102 Modified: FATTY ACID MANUFACTURE BY FAT SPLITTING
ton RECEIVING
   STOflAGE-TRANSFER
                102; FATPRETREATMENT
 IWASTEWATER I
 102X1     I
SOLID WASTE
102209
WASHINGS
W2721
                                                                                                                 FATTY AGIOS
                                                                                                                 TO SALES.
                                                                                                                 NEUTRALIZATION
                                                                                                                 OR HYDROGENATION
                                                     FIGURE   27

-------
                                               SECTION* and XI
                                             LEVEL II TECHNOLOGY
                                                    and
                                             LEVEL III TECHNOLOGY

               SCHEMATIC - 102-H: FATTY ACIDS MANUFACTURE : HYDROGENATION STEP, IF CARRIED OUT.
   RECYCLE -«	
   TO:
   DISTILLATION
   OF FATTY ACIDS
in
CD
  FATTY ACIDS

  FEED TO
  HYDROGENATION
  FROM:
  102-M
                       CATALYST
                       BED
                          OR
SUSPENDED
CATALYST
WITH
TRAYS
                                                             COMPRESSOR
    FROM
    STORAGE
                                                                       HYDROGENATED
                                                                       FATTY ACIDS TO:
                                                                       SALES OR
                                                                       NEUTRALIZATION
                                                        HYDROGENATED
                                                        FATTY ACIDS
                   HYDROGEN:
                   FROM SUPPLIER
BLEED
IMPURITIES
TO SUPPLIER
OR VENT:
TO STACK
SPENT
CATALYST
AND
POLYMERS

-------
first of these is in-process recycle of the process condensate to
the  maximum extent possible.  Secondly, the barometric condenser
of the fatty acid distillation process can  be  replaced  with  a
surface  condenser  thereby  reducing by approximately 80 percent
the amount of light ends going into the waste water stream during
acid separation  and  purification.   These  light  ends  can  be
recovered  for  sale.  The water stream can be then recycled back
into the fat splitting process.  The overall  process  (including
hydrogenation)   is  shown  in Figures 27 and 28.  Use of a liquid
film extraction unit ahead of the barometric  condenser  is  also
applicable to this subcategory.

Raw Waste Loadings

The following raw waste loadings can be expected.

BOD5 - 2.5 kg/kkg (2.5 lb/10CO Ib) anhydrous fatty acid

COD - 6.0 kg/kkg  (6.0 lb/1000 Ib) anhydrous fatty acid

Suspended Solids - 2.0 kg/kkg  (2.0 lb/1000 Ib) anhydrous
                   fatty acid

Oil and Grease - 1.5 kg/kkg  (1.5 lb/1000 Ib)  anhydrous
                 fatty acid

Best Available Technology Economically Achievable Guidelines

Please  refer  to  guidelines  in  Table 7-2 at beginning of this
Section.
   ^- GLYCERINE RECOVERY AND CONCENTRATION

Best Available Technology Economically Achievable and Rationale

Replacement  of  the  barometric  legs  in  both  the   glycerine
concentration  and  distillation processes would reduce glycerine
losses and waste water loadings substantially.  These changes are
shown in Figures 29 and 30.

Raw Waste Load

The following average raw waste load is expected:

Glycerine Concentration

BOD5 - 4.0 kg/kkg (4.0 lb/1000 Ib)  anhydrous glycerine

COD - 8.0 kg/kkg (8.0 lb/1000 Ib)  anhydrous glycerine

Suspended Solids - 1.0 kg/kkg ( 1.0 lb/1000 Ib) anhydrous
                   glycerine

Oil and Grease - 0.4 kg/kkg (0.4 lb/1000 Ib) anhydrous
                                 159

-------
                                                        104 GLYCERINE RECOVERY
1041 RECEIVING         1042  LYE TREATMENT        'O43 GLYCERINE EVAPORATION TO 80% CONCENTRATION
   STORAGE TRANSFER
                                                            SOAP MAKING
                                                            SOLUTION MAKE UP
                                                                                                                                     80% GLYCERINE TO CONCENTRATOR
                                                                                                                                     HEAVY ENDS TO FOOTS STILL
                                                                FIGURE    29

-------
                 1044 GLYCERINE STILL
                                104-B: CONCENTRATION OF 80% GLYCERINE TO 99.5%
 80%GLYCERINE
 from 104 A
HEAVY ENDS
from 104 A
FOOTS TO FLARE
OR WASH TO SEWER


STILL
CHARCOAL

1
1
1
1
1
1 1
• 1 i
GLYCERINE | SOLID WASTE
FOOTS - ,0440s
1O4423 '
FOOTS STILL \
\
COOLING TOWER!
R SLOWDOWN
1
99.5% G
TO SAL
1 	 ' 	 1
1st STAGE
SURFACE
CONDENSOR , 	
REFINED GLYCERINE ^ Op.iona, ^ 1 ™MOSPHERE




	 •- CONDENSOR VACUUM
J 	 1 	 ' PUMP
Optional )



GCONDENSATE
RECEIVER



LYCERINE U C PUMr
s
Dry C,u»,,c Soda WASH j LIQUID
CAUsTtc BLEED: TO FLARE
""**" SODA
Dry Salt

SALT
1 . F
'• s
, F
                                                                                                                  HEAVY ENDS TO
                                                                                                                  FOOTS STJLL
                                                                                                                 RECYCLE SALT TO:
                                                                                                                 SOAP MAKING
                                                                                                                 RECYCLE CAUSTIC
                                                                                                                 TO: SOAP MAKING
                                                     FIGURE   30

-------
                 glycerine

Glycerine Distillation


BOD5 - 3.0 kg/kkg  (3.0 lb/1000 Ib) anhydrous glycerine

COD - 6.0 kg/kkg (6.0 lb/1000 Ib) anhydrous glycerine

Suspended Solids - 0.4 kg/kkg (0.4 lb/1000 Ib) anhydrous
                   glycerine

Oil and Grease - 0.2 kg/kkg (0.2 lb/1000 Ib) anhydrous
                 glycerine

Best Available Technology Economically Achievable Guidelines

Please refer to guidelines in Table  7-2  at  beginning  of  this
Section.

PROCESS 106^- BAR.SOAPS

Best Available Technology Economically Achievable and Rationale

By  1983  there is an expectancy that the current relatively high
BOD5 waste load from air  scrubbing  will  be  improved  to  more
closely  match  those  operations which now are experiencing very
low  discharge  rates.   Installation  of  an  atmospheric  flash
evaporation  unit  ahead  of  the  vacuum drying unit, if such is
employed, will materially reduce  both  carryover  and  utilities
requirements.

Raw Waste Load

The following average raw waste load is expected:

BOD5 - 2.0 kg /kkg (2.0 lb/1000 Ib)  anhydrous soap

COD - 4.0 kg/kkg (4.0 lb/1000 Ib) anhydrous soap

Suspended Solids - 3.4 kg/kkg (3.4 lb/1000 Ib) anhydrous
                   soap

Oil and Grease - 0.3 kg/kkg (0.3 lb/1000 Ib) anhydrous


Begt Available Technology Economically Achievable Guidelines

Please  refer  to  guidelines  in  Table 7-2 at beginning of this
Section.

202 - AIR - SO3 SULFATION AND SULFONATION
                                 162

-------
Best Available Technology Economically Achievable Guidelines S Rationale

When vapor phase sulfur  trioxide  is  used  in  sulfonation  and
sulfation  processes,  regardless of whether or not the vapor S03
is diluted with nitrogen or air, three distinct types of feed and
reactions for the application  of  sulfur  trioxide  need  to  be
considered.    The  three  feed  stocks  involved  are  1)  alkyl
benzenes; 2) alpha or branched  chain  olefins;  and  3)  lauryl,
fatty  and/or  ethoxylated alcohols.  Please refer to figures 35-
37.

The sulfur trioxide used in these three processes using different
reactants may be prepared  in  three  different  ways.   Althouth
other methods of preparation are also possible, the following are
those  used commercially.  The first process for producing sulfur
trioxide is that of sulfur burning.  In  this  process  a  liquid
sulfur  is  vaporized and burned, usually in two stages, with air
to form a sulfur trioxide-air mixture which can be  fed  directly
in vapor form to the sulfonation/sulfation unit.

Another  source  of  sulfur  trioxide  is  that derived from high
strength oleum.  In this process,  65-70  percent  oleum  is  the
purchased  feed  component.  It is heated in a reboiler operation
to produce anhydrous vapor S03, as the concentration of the oleum
is reduced to a 20 percent or even a lower level.  The SO3  vapor
is  then  diluted  with air or nitrogen as the feed stream to the
reactor.  The sulfuric acid remaining is then sold or transferred
to a sulfuric acid manufacturer for reconstitution to the  higher
65-70 percent oleum level.

A  third  way  of  obtaining  sulfur  trioxide  is  by purchasing
stabilized  liquid  sulfur  trioxide.   This  source  of   sulfur
trioxide  can be brought in by tank cars or by an over- the-fence
arrangement.  It is of 99 percent  or  higher  purity  and  in  a
stabilized form of one of its phases.  It is stored over an inert
gas,  usually  nitrogen,  in  order  to preserve its stability in
storage while in the liquid state.

For  the  purpose  of  costing,  S03  has  been  assumed  to   be
manufactured by burning sulfur.  It was further assumed that this
does  not  add to the water effluent waste loading, since most of
the losses from carrying out the preparation of S03 would  be  in
the  vapor  phase  and  therefore concerned only with problems of
waste blowing into the atmosphere, if any.

In a sense, the purchase of sulfur  trioxide  in  its  stabilized
form  would  lead to no different degree of air or water effluent
waste.  In the case  of  sulfur  trioxide  production  from  high
concentrations  of oleum, then a reboiler reactor, which produces
the SO3 vapor, does lead to a liquid  stream  of  sulfuric  acid.
However, as stated earlier, this is generally sent over the fence
or  even  shipped  for  reconcentration  to the original strength
oleum.  It thus presents no added water effluent flow except  for
spills and accidental incidents.
                                 163

-------
 When   an   alkyl-benzene   is   employed  as  the  raw  material for
 reaction with  sulfur trioxide, as well as in the other  reactants
 mentioned    above,  there are  side  reactions  which  occur   if
 sufficient heat  removal  and   close  temperature  control  is  not
 attained.    Therefore,   generally  useful,  is the recycle of the
 cooled intermediate state alkyl-benzene  sulfonic  acid  or  the
 alkene sulfonic acid   or  the lauryl alcohol sulfuric acid back
 into the staged  reaction loop, after cooling.  In  this  way  and
 with good  temperature control, preferably in the range of 60-80 C
 (140-176 °F),  high yield of the desired products may be obtained.

 In  the case  of  alkyl-benzene  as  a feed stock, it is desired
 principally to obtain the para-substituted  product  rather  than
 those   in  other  positions on  the  benzene  ring.   If  high
 temperatures at  the surface of contact are unfortunately reached,
 there  is a strong tendency for both disproportionation  and  ring
 isomerization  in  the   case  of  alkyl-benzene  feed  stock.   In
 addition to the  desired  mono-substituted  alkyl-benzene  sulfonic
 acid,   a   fair  amount   of  anhydrides  of sulfonic acid are also
 obtained.    These  are    essentially   the   anhydride   of   two
 alkyl-benzene  sulfonic  acid  molecules.  These anhydrides must  be
 hydrated with  water or otherwise reacted,  in  order  to  produce
 alkyl-benzene  sulfonic   acid of good quality.  This reaction  to
 produce the anhydrides is the result of the affinity  for  sulfur
 trioxide   in  the liquid phase to react with water, extracting  it
 from combined  hydrogen and  hydroxyl  groups,  to  form  sulfuric
 acid.   The sulfuric  acid in the water phase cannot be reverted
 but must instead be decomposed by the dilution or hydration  with
 added  water in a separate step.

 When   either  an alpha olefin or a branched chain olefin is to  be
 sulfonated, several  side reactions  occur  which  diminish  the
 product quality and  result in by-products which must be dealt
 with.   The principal reaction besides that of the sulfonation   of
 the  olefin to  produce the  alkene-sulfonic acid in the terminal
 bond position  of the olefin,  is that of bond migration where  the
 sulfur trioxide reacts and moves  along the chain, so that  no
 longer does one  obtain a terminal sulfonic acid product  but  one
 which   is   branch  chained at the position of the sulfur trioxide
 addition.

 Another reaction forming undesirable by-products that occurs with
 sulfur trioxide  and  an   olefin  is  that  of  the  formation   of
 sultones,   which are  a cyclyzed  form  of the thiolone.  These
 appear generally in three of  their most stable  forms,  that  is,
 alkyl-  propane  sultone,   alkyl-butane   sultone   and   also
 octane-alkyl sultone, all of  which must first be destroyed before
'a useful product can be  obtained.

 The conversion of sultones is accomplished  by  direct  reaction
 with   caustic  soda or sodium  hydroxide, which produces the sodium
 hydroxy-sulfonate of the alkene product together  with  a  sodium
 alkene sulfonate  in  stoichiometric  proportions.   The  normal
 reaction   product,  alkene  sulfonic  acid,   is   simultaneously
                                  164

-------
neutralized  with  caustic soda to form the desired sodium alkene
sulfonate and water.

In the case of  sulfation  reactions  in  which  an  alcohol,  an
ethoxylated   alcohol  or  an  ethoxylated  phenol  is  used  for
sulfation with sulfur trioxide, the product formed is an  organic
sulfuric  acid.   In this case, the same by-products can occur as
with oleum sulfation.

The reaction products from the alpha olefin  or  branched  olefin
must  first  be  neutralized to produce the desired sodium alkene
sulfonates before further hydration, whereas in the case  of  the
direct  reaction  of  sulfur  trioxide  with  alkyl-benzene,  the
neutralization can follow hydration steps.  Of course, an organic
sulfuric acid requires no hydration.

In all cases of these three reactions there is usually a  holding
tank  after  a cyclone separation of vapor SQ3 that is unreacted,
and the liquid streams of product and sulfuric  acid.   For  this
reason  the  holding  tank provides not only additional residence
time for the completion of the formation  of  sulfonic  acids  or
alkyl alcohol sulfuric acid, but completes the reaction so that a
recycle  stream  can  be  returned  to the sulfonator or sulfator
stage in order to get increased heat transfer  and  diminish  the
possibility of double substitution of a sulfonic acid group.

Some of these reactions are carried out simultaneously in certain
instances  because  alkyl benzene sulfonate and the fatty alcohol
sulfates are both often blended for a better balanced  detergent.
This blending can best be done after the reaction loop but before
the  hydration  and  neutralization  steps, and leads to superior
blended products.

The neutralization of the reaction can be carried  out  with  any
alkaline  neutralizing  agent depending upon the product desired.
For example, caustic soda, as earlier  described,  aqua  ammonia,
which  will lead to the formation of an ammonium salt; potassium,
or even ethanol amines can be used.   In  addition,  when  liquid
detergents  are  being  made,  substances  such  as low molecular
weight  alcohol,  urea,  toluene  and/or  xylene  sulfonates  for
hydrotropic  agents  can  be  also  simultaneously made in tandem
operations and blended before hydration and neutralization.

The most feasible means of decreasing water effluent contaminants
and simultaneously of increasing the quality of the  product,  as
it  applies  either  to a batch or a continuous system assumed in
BPCTCA technology, is the addition of dilution  in  the  reaction
step, increased agitation to diminish temperature elevations as a
result  of  the  exothermal  nature  of  the  reaction, or better
contact between the vapor sulfur trioxide and the liquid reactant
phases.  Additionally, a batch  counter-current  process  can  be
installed  by  utilizing two or more reaction loops, in which the
fresh sulfonic acid in the form of sulfur trioxide, is introduced
into the stream to the completion stage or holding stage  of  the
                                 165

-------
reaction  in  counter- cur rent  to the feed of the alkyl- benzene,
the  olefin,  or  a   fatty   acid   alcohol.    Such   a   batch
counter-current  arrangement  is  easily  feasible  and should be
economically viable by the addition of one or more small reaction
loops for a second and even third stage of the process.

Raw Waste Loadings

The following average raw waste loadings can be expected:

BOD5 - 1.9 kg/kkg (1.9 lb/1000 Ib) anhydrous product

COD - 3.7 kg/kkg (3.7 lb/1000 Ib)  anhydrous product

Suspended Solids - 0.2 kg/kkg (0.2 lb/1000 Ib) anhydrous product

Surfactant - 1.8 kg/kkg (1.8 Ib. 1000 Ib) anhydrous product

Oil and Grease - 0.4 kg/kkg (0.4 lb/1000 Ib) anhydrous product

Best Available Technology Economically Achievable Guidelines

Please refer to guidelines in Table 7-2 in this section.

PROCESS 203 - S03 SOLVENT AND VACUUM SULFONATION

PROCESS 204 - SULFAMIC ACID SULFATION

PROCESS 205 - CHLOROSULFONIC ACID SULFATION

Best Available Technology Economically Achievable

Improved process control should reduce the waste loading.

Raw Waste Load

The following average raw waste loads are  expected   (all  values
given in kg/kkg, lb/1000 Ib of product produced) .

       BQD5    COD    Suspended    Surfactant   oil &
       ~~                                        Grease
203    1.0     3.0      0.1          0.1         0.2
204    1.0     3.0      0.1          0.1         0.2
205    1.5     5.0      0.2          1.5         0.3

Best Available Technology Economically Achievable Guidelines
Please  see  guidelines  in  Tables  7-1  and 7-2 at beginning of
Section.

PROCESS 207 - SPRAY DRIED DETERGENTS
                                166

-------
 (AIR QUALITY RESTRICTION OPERATION)

Best Available Technology Economically Achievable and Rationale

As discussed in Section VII, installation of tandem chilled water
scrubbers   (one  with   high   and   one   with   low   detergent
concentration)  to  scrub  the  plume  will  enable  meeting  air
pollution  restrictions  while  materially  reducing  the   water
effluent load.

Raw Waste Load

The following average raw waste load is expected:

BOD5 - 0.6 kg/kkg  (0.6 lb/1000 Ib) anhydrous product


COD -2.5 kg/kkg (2.5 lb/1000 Ib) anhydrous product

Suspended Solids - 0.7 kg.kkg (0.7 lb/1000 Ib) anhydrous
                   product

Surfactant - 1.0 kg/kkg (1.0 lb/1000 Ib) anhydrous product

Oil and Grease - 0.2 kg/kkg  (0.2 lb/1000 Ib) anhydrous
                 product

Best Available Technology Economically Achievable Guidelines

Please  refer  to  guidelines  in  Table 7-2 at beginning of this
Section.

PROCESS 208 - LIQUID DETERGENTS

PROCESS 211 - DETERGENT BARS AND CAKES

Best^Available Technology Economically,Achievable and Rationale

Guidelines recommendations for both processes were reduced on the
basis of expected greater control over product losses in  washups
and  general  manufacturing,  including  employment of technology
covered under Bar soaps.

Raw Waste Load

The following raw waste loads are expected  (all values  given  in
kg/kkg, lb/1000 Ib of anhydrous product.)

            BOD5    COD    Suspended    Surfactant   Oil.6
                            Solids                   Grease

208         0.5     1.5      	          0.5        	
211         3.0     9.0      1.0           2.0        0.2
                                 167

-------
Best Available Technology Economicallv Achievable Guidelines

Please refer to guidelines in the Table 7-2 at the beginning of this
section.
                                168

-------
                           SECTION XI

                NEW SOURCE PERFORMANCE STANDARDS

                   AND PRETREATMENT STANDARDS

Introduction

New  source  performance standards (NSPS), being that which would
be employed in a new source of manufacture, offers an opportunity
to  start  afresh  in  the  design  of   production   facilities.
Reviewing   candidate   processes  for  minimized  effluents  has
produced no great surprises.  Soap and detergent making is a well
established  art.   Still,  a  number  of  relevant,  substantive
concepts for improvement have emerged as well as a few fairly far
from  commercial  realization.   Bearing in mind the necessity of
being very practical, in the discussion of all newer developments
for NSPS, particular note has been made of the  degree  to  which
each   technique   has  been  reduced  to  acceptable  commercial
practice.  The  technology,  in  most  categories,  reflects  the
improvements  developed in best available technology economically
achievable.  The guidelines for many of these subcategories  will
be  the same for the two groups of technology.  To simplify study
of the recommendations, the guidelines are  reported  in  tabular
form  with  the  processes  given  new  limitations  and  special
consideration in the text noted by an asterisk.  The  sign  a)  in
the  table  indicates that the 1983 and new source guidelines are
identical.   Please  refer  to   the   corresponding   guidelines
discussion in SECTION X for extensions and exceptions recommended
for the guidelines.  These exceptions are applicable to both sets
of guidelines.

Following the discussion of specific process improvements for new
source  performance  standards  is  a review of process chemistry
developments which deserve further continuing study for  ultimate
improvements  in  low  effluent level products.  As with all such
"far  out"  developments,  some  of  the  concepts  have  greater
probability  for  success  than others.  They are offered for the
different perspectives they offer to this  sophisticated  art  of
soap and detergent manufacturing and formulating.
                               169

-------
                             TABLE 8

           New Source Performance Standards^Guidelines

Note:   All  values  reported  are  in  kg/kkg  (lb/1000  Ib)   of
anhydrous product made in that category.   For all categories  the
guidelines pH is 6 - 9.
                                        Suspended                  Oil 6
                          BODJ5   COD      Solids     Surfactant   Grease

   Batch Kettle and
     Continous Soapa      0.40   1.05     0.40           —       0.05
   Fatty Acid By Fat
     Splitting®           0.25   0.90     0.20           —       0.15
   Soap From Fatty
     Acid Neutrali-
     zations              0.01   0.05     0.02           —       O.C1
   Glycerine Recovery
      Concentration®      0.40   1.20     0.10           --       0.04
      Distillationa       0.30   0.90     0.04           —       0.02
   Soap Flakes And
     Powders®             0.01   0.05     0.01           —       0.01
   Bar Soaps®             0.20   0.60     0.34           —       0,03
   Liquid Soapa           0.01   0.05     0.01           —       0.01
   Oleum Sulfation/
     Sulfonation*         0.01   0.03     0.02          0.01      C.04
   Air-SO3 Sulfa-
     tion/Sulfonation*    0.09   0.40     0.09          0.09      C.02
   SO3. Solvent and
     Vacuum Sulfona-
     tiono)                0.10   0.45     0.01          0.10      0.02
   Sulfamic Acid
     Sulfationa           0.10   0.45     0.01          0.10      0.02
   Chlorosulfonic
     Acid Sulfationa      0.15   0.75     0.02          0.15      0.03
   Neutralization
     Of Acidsa            0.01   0.05     O.C3          0.02      0.01
   Spray Dried
   Detergents
    Normal®               0.01   0.08     0.01          0.02      0.005
    Air Quality
       Restricted®        0.08   0.35     0.10          0.15      0.03
    Fast
     Turnaround®          0.02   0.09     0.02          0.03      0.005
   Liquid Deter-
     gents®               0.05   0.23     0.005         0.05      0.005
   Detergent Dry
     Blendinga            0.01   0.08     0.01          O.C1      0.005
   Drum Dried
     Detergents®          0.01   0.05     0.01          O.C1      0.01
   Detergent Bars
     and Cakes®           0.30   1.35     0.10          0.20      0.02

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PROCESS DISCUSSION

SOAP MANUFACTURE_BY_BATCH_KETTLE

Soap Manufacture lay Continuous Counter-Current^Process

There  appears  to  be  little  economic  driving  force  for the
construction  of  a  totally   new   batch   soap   manufacturing
installation,  from  fats  and  oils, in the United States in the
foreseeable future.  There will be replacement of some pieces  of
equipment  as  maintenance demands.  Soap use is expected to hold
constant  at  best.   Particularly  in  toilet  bars,  there   is
continuing  loss of soap volume to synthetic detergent bars where
the hard water problems are severe.

A totally new installation, starting with  fats  and  oils,  will
most  likely  be  a  continuous  manufacturing process.  Although
initial capital investment and operating  costs  are  the  lowest
attainable,  use  of  a  continuous unit entails the sacrifice of
some manufacturing flexibility.   For  example,  changeovers  are
accomplished  more  conveniently and/or economically with a batch
kettle when it is desired to make  a  number  of  different  base
soaps,  each  of  which  requires  different  fatty raw materials
input.

Technically, a continuous unit possesses  two  major  advantages.
It  uses  very little water, thus minimizing the problem of waste
water disposal.  Secondly, as the nigre is formed entirely  in  a
solid  state, its handling is greatly simplified.  In areas where
there is little or no market for  the  dark  soaps  derived  from
nigre,  this  is a distinct advantage.  Please refer to Figure 33
for process details.

Manufacturing operations still require preliminary  fat  refining
and  bleaching, as shown in section 1012 of the schematic diagram
for soap manufacture  by  batch  kettle.   Therefore,  the  waste
streams  from  this  process  can be minimized only to the extent
described in best available technology  economically  achievable.
The volume of waste water currently generated by the batch kettle
process  can be reduced about 80 percent.  Utilities are expected
to run no more than 0.4U0 to 0.660/kkg (0.20 to 0.30/1000 Ib)   of
neat   soap.   Electricity  use  is  somewhat  increased  by  the
requirements of the turbo-disperser  motors  and  those  for  the
centrifuge  operations.   This  added cost would be. approximately
0.220/kkg (0.10/1000  Ib)   of  soap  product  according  to  best
estimates.

A  significant  reduction  in operating cost would be expected in
the substitution of the continuous processing for a batch  kettle
from  reduced  labor requirements.  Instead of labor in the range
of eight to ten men per shift for a kettle plant of  circa  9  to
13.6  M kg (20 to 30 M Ib)  capacity per year or higher, it should
                                   171

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be no more than two  or  possibly  three  men  per  shift  for  a
continuous  unit,  representing  a  striking  reduction  in labor
costs.  Through labor savings alone,  capital  investment  for  a
continuous soap process should be recovered within ten years.

Realizing  that  improvements  in  the  clay treatment and vacuum
bleaching  of  the  feed  oils  and  fats  are  limited  to   the
replacement  of  a  barometric  condenser  by a two-stage surface
condenser, and that only good operating cleanliness  can  further
reduce  the  raw  waste  load,  the  best  available demonstrated
control technology guidelines  consider  a  small  allowance  for
wastes  from  fats and oils pretreatment but essentially none for
the continuous saponification process.

By  the  use  of  centrifugation,  the  soaps  or  fats  can   be
effectively  separated from the salt and lye.  Thus, all of these
materials can be reprocessed and it would appear that recommended
guideline levels that could  easily  be  met  in  the  continuous
saponification  plant  are:  BODS, 0.20 kg/kkg; COD, 0.60 kg/kkg;
suspended 'solids, 0.20 kg/kkg; and oil and grease, 0.05 kg/kkg.

Raw Waste Load

The following average raw waste load can be expected:

BOD5 - 2 kg/kkg (2 lb/1000 Ib) anhydrous soap

COD - 4 kg/kkg (4 lb/1000 Ib) anhydrous soap

Suspended Solids - 2 kg/kkg  (2 lb/1000 Ib) anhydrous soap

Oil and Grease - 0.5 kg/kkg  (0.5 lb/1000 Ib) anhydrous soap

SOAP FROM FATTY ACID NEUTRALIZATION

General

In BADTC  technology  the  manufacture  of  soap  by  fatty  acid
neutralization  is  regarded  as  the norm for the preparation of
neat soap.  It is depicted in Figure 3U.  Data reported here is a
combination of field visits and contractor's  engineering  design
parameters.  Data from two installations has been integrated with
additional information found in the literature.

BADTC Technology - Soap Manufacture

The  continuous  process  makes  use  of proportioning pumps with
interlocks and main control-interlocks for absolute rate of feeds
flow,  very  similar  to  that   outlined   in   the   continuous
saponification process.  In this process turbodispersers are used
which greatly enhance the contacting efficiency between the water
and fatty acid or oil phases of the reactants.  The reaction time
is  reduced  to  a  matter  of  10 to 15 minutes total within the
reactor and separation systems.
                                   172

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The quality of product made from such a continuous  operation  is
equivalent  to  or improved over that from the batch kettle.  For
example, the batch kettle  process  will  result  in  an  average
content  of free alkali, measured as Na20, of 0.5 percent to 0.75
percent.  In the case of the continuous  manufacturing  operation
(representing  an  average  range of all contractors' claims) the
free alkali is reduced tenfold to approximately 0.05  percent  to
0.075  percent.   Similarly,  the  salt content is reduced from 1
percent to  0.5  percent.   The  neat  soap  produced  from  this
reaction  needs  to  be dried from approximately 35 percent water
content to the desired level.  The drying process  is  considered
separately.

Battery  limit  capital investment, including appropriate tankage
for the reactants, will cost  approximately  $500,000  for  a  20
million  pound  per  year  plant.   Direct  operating  labor will
approximate  $60,000  per  year  using  standard   labor   costs.
Appropriate  maintenance and administration costs would equal the
direct labor costs.  It is estimated that steam consumption  will
amount    to   approximately   $6,000   per   year;   electricity
approximately $10,000 per year, and cooling  water  approximately
$2,000 per year for a, 20 million pound per year installation.  It
must  be emphasized that this covers only the neutralization step
for production of neat soap from fatty acids.

BAR SOAP - DRYING

The  drying  operation  is  no  different  than  that  in   BATEA
guidelines  for  solid bar soap manufacture.  A surface condenser
is indicated for use in place of the normal barometric  condenser
now  generally  utilized  for soap drying, especially when vacuum
drying operations are carried out for clear soaps.

The  capital  cost  for  the  above  drying  operation  (for  the
production  of a bar soap extrudate)  is estimated at $200,000 for
9 M kg (20 M Ib)  per year of anhydrous soap capacity.   Operating
steam,  electric  and  cooling  water costs are the same as those
shown for best available technology economically achievable.

SOLVENT PROCESS FOR SOAP MANUFACTURE

A process developed in the  1940's  requires  no  water  to  make
anhydrous soap and dynamite glycerine.

In the Kokatnur process fats or oils dissolved in heated kerosene
(260-290C)   (500-554F)   are  mixed  under pressure with anhydrous
caustic soda.   The  reaction  takes  place  in  ten  minutes  and
produces   dynamite  grade  glycerine.   After  drawing  off  the
glycerine,  the remaining mixture is released  into  an  expansion
chamber  where evaporation of the kerosene yields anhydrous soap.
The process has the following advantages:

1.  Very short reaction time.
                                   173

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2.  Use of kerosene prevents charring.

3.  Absence of water reduces heat requirement.

U.  Dynamite grade glycerine and anhydrous soap are obtained directly.

One major defect of the process is  that  there  is  no  refining
stage  and  traces  of  kerosene  are left in the soap, making it
impossible to market the product for  toilet  bar  use.   without
further   refinement  the  soap  is  suitable  only  for  limited
industrial uses.

201!..r_-QLEUM SyLFATION^AND_SULFONATION

Extensive contractor data indicates that, with  good  engineering
design  of  the  reactor  and  a  minimum residence time prior to
neutralization, the levels proposed for raw  waste  load  can  be
readily met by a continuous process plant.

Compared  to  those for batch or semi-batch reverse feed systems,
capital investments for a continuous process are estimated to  be
lower  by  $66/kkg ($30/1000 Ib) of annual capacity.  Operational
savings are possible in the form of reduced  labor  costs,  lower
consumption  of  utilities,  and  higher conversion of feedstocks
(0.8 to 1.0 percent)  to products.

The  continuous  process  is  adaptable  to   almost   any   size
installation from 90C thousand kg (2 million Ib)  per year upward.
Please refer to Figure 35.

Raw Waste Loadings

The following average raw waste load can be expected:

BODJ5 - 0.1 kg/kkg (0.1 lb/1000 Ib) anhydrous product

COD - 0.2 kg/kkg (0.2 lb/1000 Ib) anhydrous product

Suspended Solids - 0.2 kg/kkg (0.2 lb/100C Ib) anhydrous
                   product

Surfactant - 0.1 kg/kkg (0.1 lb/1000 Ib) anhydrous product

Oil and Grease - 0.4 kg/kkg (O.U lb/10CO Ib) anhydrous
                   product

S02_AIR;S03 gULFATIQN_AND^SyLFONATION


BADTC guideline recommendations are based on process chains shown
in  Figures  35,  36  and  37.   The  process  chain involves the
reaction,  hydration,  neutralization  and  finishing  steps  for
production of alkylated aromatics.
                                 174

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Neutralization

NSPS   guideline   recommendations   are  based  upon  technology
illustrated in Figures 35-37 related  earlier,  each  covering  a
separate feed stock, i.e., alkyl aromatics, olefins and alcohols.
The  process  variations reflect the particular chemical reaction
characteristics of the feed stocks.

In an integrated plant utilizing products containing  derivatives
of  all  three feed stocks, superior blended products can be made
by combining the reaction products after the  reaction  loop  but
prior  to the hydration and neutralization steps.  This procedure
is  particularly  applicable  to  the  blends  of  alkyl  benzene
sulfonate with fatty alcohol sulfates.

Performance   of   a   new  installation  based  upon  continuous
sulfonation/sulfation is expected to be improved moderately  over
already  installed  batch  or batch counter current systems.  The
form of sulfur trioxide used  will  not  influence  the  effluent
water quality.


The  cost  depicted  and  guaranteed  by a supplier shows utility
demands as follows; electricity 0.9 to 1.1£/kg (0.4 - 0.50/lb) of
active material from the reaction; cooling water requirements  of
0.1  -  0.22/kg (0.05 - 0.100/lb) of active product.  The initial
capital cost for this installation relates  of  course  to  plant
size  with economy of scale favoring large plants.  For plants in
the size range of 13.6M kg per year (30M Ib per year)   of  active
ingredient,  and  based  upon a 92 percent stream factor, capital
amounts  to  $88-110/kkg  ($40-50/1000   Ib)    annually   product
capacity.

Use  of  stabilized liquid sulfur trioxide is assumed.  If sulfur
trioxide is produced by sulfur burning, this is considered to  be
a  separate unit, and the economics and the justification covered
in the water effluent.
Raw Waste Load

The following raw waste load can be expected:

BOD5 - 0.9 kg/kkg (0.9 lb/1000 Ib) anhydrous product

COD - 2.7 kg/kkg (2.7 lb/1000 Ib) anhydrous product

Suspended Solids - 0.9 kg/kkg (0.9 lb.1000 Ib)  anhydrous
                    product

Surfactant - 0.9 kg/kkg (0.9 lb/1000 Ib)  anhydrous product

Oil and Grease - 0.2 kg/kkg  (0.2 lb/1000 Ib)  anhydrous
                    product
                                 175

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                                              SECTION X and XI

                                            LEVEL II TECHNOLOGY
                                               and
                                            LEVEL III TECHNOLOGY

                                        SCHEMATIC FLOW DIAGRAM - 2O1 and 206

                             CONTINUOUS DETERGENT SLURRY PROCESSING PLANT

                             HIGH-ACTIVE ALKYLATE SULFONATION WITH OLEUM : FEED A_

                                              LOWNa2S04 CONTENT
                                                                                                206-A: Neutralization
Modified 201 A: SULFONATION
NEUTRALIZED
DETERGENT
SLURRY
                                              FIGURE

-------
                                              SCHEMATIC FLOW DIAGRAM— 201 MODIFIED

                                    CONTINUOUS DETERGENT SLURRY PROCESSING PLANT

                                       FATTY ALCOHOL SULFATION WITH OLEUM : FEEDS B and C
FATTY ALCOHOL
FROM STORAGE
OLEUM
FROM
STORAGE
                    PROPORTIONING
                    PUMP
                                                                                                              NEUTRALIZED
                                                                                                              DETERGENT
                                                                                                              SLURRY
                                                                ALKALI
                 Modified: 201-B and C : SULFATION
                                                                       201-B and C : NEUTRALIZATION
                                            FIGURE   32

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                                                     SECTION XI
                                               LEVEL III TECHNOLOGY

                                   108: SOAP MANUFACTURE BY CONTINUOUS SAPONIFICATION
toil RECEIVING
   STORAGE-TRANSFER
toil FAT REFINING
  AND BLEACHING
	 3

31 LS
ED
OILS
OILS
IDS
SIM
DFATS

k




^



1ft STAGE
KILL
1 LJ=
TURBO
DISPER
SER
t


SI
G
t





i

2nd STAGE
STRONG
CHANGE
1
TURBO
DISPER
SER




*ENT LVE AND
LVCERINE



;*-

1

>d STAGE
WEAK
CHANGE

L
TUHBO
DISPER
(SEW
_4_
1

*
I

4rt> STAGE
FITTING:
BALANCE


1 ,




-1 	 ,
CENTRIFUGE | 	


	 -»* T0
                                                                                                                                        NEAT SOAP
                                                                                                                                        FROM
                                                                                                                                        REACTION
                                                                                                          LEAKS. SPILLS. DRAINS.
                                                                                                          CONCKNSATES. STEAM

-------
                                                   SECTION XI
                                              LEVEL III TECHNOLOGY
           103 Modified: SOAP BY CONTINUOUS FATTY ACID NEUTRALIZATION
FEU RECYCLE   I

 t_«4_
 1    FATTY ACM* -
rvACto
r ;
&. 	 [
n> RECCrVMG
STOHAGf TRAMWE1

INTERLOCKED
rROPORTtONING PUMPS MASTER
A t



puwr

A
-d



r


>]
J-
•|_
—
3 r
•u



b
SEQUENTIAL
-., 	 Ofl _
/ TANDEM
VENT 0««*"0"
M STAGE
REACTION
TOWER


1

rURBO
DISPERSE R
-


PU
^ »
:
•\

!•>
Cvton
O»xid«
«A«
V*M
t
<*>,
SEM-
T^;10" sss«|-
i .1. •
                                                                                            Section 1062-Modified:

                                                                                   NEAT SOAP DRYING: FOR BAR SOAPS
                                                                                                                    TO
                                                                                                                    ATMOSPHERE

                                                                                                             LIGHT ENDS
                                                                                                             RECYCLE OR
                                                                                                             FLARE
o
c:
8
u>

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                                                                  SECTION XI


                                                            LEVEL III TECHNOLOGY




                                                                COMBINED PROCESSES


                                       Modified 202 : SOg - SULFONATION / SULFATION PROCESSES - CONTINUOUS



                                                                       AND


                                       Modified 206 : NEUTRALIZATION OF SULFONIC OR ALKYL SULFURIC ACID PROCESSES - CONTINUOUS
                                                             TO SCRUBBERS
        202A and 2O6A : SCHEMATIC FLOW DIAGRAM


        Modified ALKYL BENZENE SULFONATION



        Reaction: 202 A Section
HI
1-1
o
                      SULFONATION
                                                                              DIGESTOR
                                                                            DIGESTION
                                                                                                   HYDRATOR
    NEUTRALIZATION: 206 A Section
                                                                                                                                                    PRODUCT
                                                                                                                                 ->  PUMP
                                                                                                                WATER
                                                                                                  HYDRATION
CAUSTIC SODA

NEUTRALIZATION

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                                                                SECTION XI

                                                          LEVEL III TECHNOLOGY


                                                          SCHEMATIC FLOW DIAGRAM

                                                      202 C and 206 C: Modified - Combined

                                                  FATTY ALCOHOL SULFATION : WITH SO,
                            Reaction : 202 C  Section
                                                                                                 Neutralization : 206-C  Section
no FATTY
—• ALCOHOL
    S03-AIR
                                                               TO SCRUBBER
O
CO
cr>
                                                                                                                            PRODUCT

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                                                        SECTION XI
                                                  LEVEL III TECHNOLOGY

                                         SCHEMATIC FLOW DIAGRAM - COMBINED 202B and 206B

                                           ALPHA - OLEFIN SULFONATION WITH SO,
                             Reaction: 202 B Section
                                                                                Neutralization : 206 B Section
   ALPHA
   OLEFIN
00
ro
O

I
                                                                                                                    •> PRODUCT

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PRETREATMENT REQUIREMENTS

In this section of the report those pollutants  capable  of  dis-
rupting,  or likely to disrupt, the operation of a publicly owned
waste water treatment  plant  are  cited.   It  should  be  fully
understood  that  it is not the intent to provide limits or other
standards which would in effect supplant any sewer use  ordinance
developed  and  now  being  enforced  by a central authority.  In
fact, every authority that owns a collection and treatment system
should have an up-to-date sewer use ordinance which would  enable
it  to  regulate  the  types  and  quantity  of industrial wastes
admitted to its system.  The purpose of this section is to  point
out  possible  problem  areas  and  indicate  applicable  control
measures.

With  the  exception  of  dissolved  mineral   salts   there   is
essentially  no  pollutant  in the wastes from soap and detergent
manufacturers that cannot be removed at high levels of efficiency
in a central plant.

Fats and Oils

Fats and oils from soap plants are readily degradable.   whenever
excessive  fats,  oils  or  greases are discharged, or whenever a
safeguard against such a discharge is required, the waste  should
be  passed through a gravity type separator prior to discharge to
the central system.  This type of pretreatment serves  to  remove
up to 90 percent of the free oils which are the primary source of
problems in both sewers and the treatment plant.

As previously discussed, the well-designed fat trap is similar to
a  primary  clarifier  in a municipal plant.  An appropriate size
for a large soap plant would be rated  2078  1/day/l  sq  m  (600
gallons/day/square foot).  Residence time should be about 1 hour.
Such  a  fat  trap, with a radial flow to the perimeter discharge
weir and a rotating scraper arm which  moves  the  fat  layer  in
front of the arm and thence into a well, will do an excellent job
and provide essentially complete removal.

The  underflow  from  such  a fat trap will have a high treatable
concentration of biodegradable organics.   In  one  of  the  soap
plants  observed  in  this  study  a  reserve of the underflow is
retained in tanks to be used as a feed for the biological treater
when only a few units of the plant are operating.

If the pollutant is a low molecular weight mineral solvent  which
has  a  low  water solubility the same treatment mechanism can be
employed.  The captured material should be  burned  or  processed
for  reuse.   The  non-flotables  and  the liquid phase should be
passed on to the central treatment plant.

The efficiency of the fat trap must  be  maintained  and  routine
inspections should be made by the proper authorities.
                                 183

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Fats and Oils - Detergent Plants

Detergent plants will have oil and grease effluents more like the
hydrocarbons   encountered  in  the  organic  chemical  industry;
namely, they will be of fossil or petroleum  origin  rather  than
from  natural  fats.   These  hydrocarbons  are  not  as  readily
degraded as those originating from  the  soap  plant.   The  only
analytical  method,  as  described  in Standatd Methods, makes no
differentiation between the two  types  of  hydrocarbons.   Until
such  a  test can be devised it would be unfair to set a standard
based  on  the  least  degradable  product  and  make  the   more
degradable product conform to it.  Additionally, from am economic
standpoint  it  is  most  important  to make a differentiation in
treatability.  The problem is accentuated in that the  industrial
detergents  will  probably contain more hydrocarbons extracted in
the hexane extractable test that are difficult  to  degrade  than
will the household detergents.

Zinc

Concentrations  of  zinc  which  could  lead  to  problems at the
central facility have not been found in the waste water  examined
or  in  the  data analyzed.  The best information available would
indicate that zinc concentrations of between 5 and  100  mg/1  in
the  biological  portion of the central plant could slow the rate
of assimilation.  Therefore, any concentration of not more that 5
mg/1 would appear to be a satisfactory  process  effluent  level.
The observed values have been less than U mg/1.  The relationship
of  zinc to the activity of nitrifying bacteria is under study in
EPA.  The results could have an effect on this standard.

Should a zinc  problem  arise,  pretreatment  employing  alkaline
precipitation is the most effective means of reducing zinc levels
to  satisfactory concentrations in process effluent.  This should
be  carried  out  at  pH  values  between  8.5  and  9.5  in  the
coagulation unit and at surface loadings of 1627 1 - 20377 1/sq m
(400-5000  gpd/sq  ft)   in  the  sedimentation  unit.  The sludge
should be dewatered and incinerated or dried prior to disposal as
a solid waste.
Industrial and Institutional Cleaners

A number of soap  and  detergent  manufacturers  studied  produce
industrial  cleaners  which  contain  phosphoric and hydrofluoric
acids;  and  organics  such   as   chlorinated   benzenes.    The
implication  of  the  first  two substances is clear and whenever
they are used, strict in-house control steps should be excercised
to control their discharge.  The problem of  chlorinated  organic
discharge  is  potentially more serious.  These materials used in
such applications as acid cleaners are moderately to highly toxic
to man and may have  a  deleterious  effect  on  waste  treatment
plants and on receiving waters.  It is expected that treatability
of   these   compounds   is   being  studied  by  the  industries
                                  184

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manufacturing them.  It is suggested that further  definition  of
their  impact,  and  discussions  of  in-house  and  pretreatment
control measures await the completion of those studies.

Many  insitutional  cleaners  may  have  biocidal  or   biostatic
materials incorporated in their formulation, and relatively large
amounts  of  such  materials  in a discharge could interfere with
normal operation of biological treatment systems.  As in the case
of  industrial  cleaners,  strict  in-house  control  should   be
exercised to control discharge of these materials.

Should  pretreatment  be necessary for industrial and institution
cleaners, it would have to be in the nature of  chemical-physical
treatment designed to remove the specific materials involved.
                                 185

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                           SECTION XII

                        ACKNOWLEDGEMENTS

The  Environmental  Protection  Agency  wishes to acknowledge the
contributions to the project by Colin A.  Houston  6  Associates,
Inc., Mamaroneck, New York.  Messrs. Colin A.  Houston, Frederick
C.  Herot,  Charles H. Daniels and Ms. Susan M. Weisman, with the
able assistance of their consultants Mr. George c. Feighner,  Dr.
Allen  W.  Fleer  and  Mr. Robert W. Okey, conducted the detailed
technical study and drafted the  initial  report  on  which  this
document is based.

Because  of  the  wide-ranging  scope  of  the  study,  there was
occasion to call upon  many  individuals  and  organizations  for
assistance  in  the  course  of  bringing it to completion.  Many
people,  both  as  individuals  and   as   members   of   various
organizations, responded with the utmost courtesy and generosity.
We  regret  that space does not permit their individual citation,
but the debt owed to each and every one  of  them  is  gratefully
acknowledged.

Throughout the country, soap, detergent and fatty acid producers,
large   and  small,  graciously  assisted  in  providing  process
information and opening up their plants  to  detailed  study  and
sampling.   Three  trade  associations performed valuable liaison
functions in making the project a truly cooperative one; the Soap
and Detergent Association, the Chemical Specialties Manufacturers
Association, and the International Sanitary Supply Association.

Special help was  received  from  members  of  the  Environmental
Protection  staffs  in  Regions  II,  IV,  V, VI and VIII.  As an
example, Mr. William Cloward, Chief,  Industrial  Waste  section,
Region  IV,  actively  contributed  to all stages of the project,
including participation in the in-plant sampling  program.   Many
of  the  accomplishments of the sampling program are attributable
to the  assistance  and  analytical  support  received  from .the
laboratory  of the Division of Water Pollution Control, Louisiana
Wildlife and Fisheries Commission, Baton Rouge, Louisiana and the
following   Environmental   Protection    Agency    laboratories:
Analytical  Quality  Control Laboratory, Cincinnati, Ohio; Robert
S. Kerr Water Research center, Ada, Oklahoma;  and  the  Regional
Laboratories  in Athens, Georgia; Evansville, Indiana; Annapolis,
Maryland and Kansas City, Kansas.

A  lasting  indebtedness  is  acknowledged  to   those   in   the
Environmental  Protection Agency who assisted in the project from
inception of the study through  preparation  and  review  of  the
report.   Especially  deserving  recognition are:   Ms. Jan Beale,
John  Ciancia,  Ms.  Patricia  Dugan,  Ernst  Hall,   Ms.  Frances
Hansborough,  Richard  Insinga, Thomas Kopp, Ray McDevitt, Ronald
McSwinney, David Mears, John Riley, Ms.  Jaye Swanson  and  George
Webster.
                                 187

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                          SECTION XIII

                           REFERENCES

 1.  Adams, Roger, et al. Organic Reactions.  Vol. IV.
     John Wiley and Sons (1948).

 2.  Air Plastics, Inc.  c^pj-nnatif Ohio.  Pollution
     Control Equipment.  Brochure No. 7201A.January 22
     (1973)

 3.  Air Pollution Control District, County of Los Angeles,
     California.  Concentration and Flow Rates of Particu-
     late Matter; Tests at Plant G.  March 16, (1973)

 4.  Altman, Philip L. and Dittmer, Dorothy S.  Environ-
     mental Biology.  Federation of American Societies for
     Experimental Biology.Bethesda, Maryland.(1966)

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10.  Ballestra, M.  Sulfonic Acids Neutralization with Sodium
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                                189

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14.   B}.ack, J. F. Radio-chemical Production of Sulfonates
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15.   Black, J. F. Radiation source for Sulfonation Using
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16.   Blakeway, et al.  Jet Reactor for Sulfonation.
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17.   Blinoff, V.  Sulfate Neutralization with _Sodluni  Bi-
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18.   Ballestra, SPA.  Manufacture of Synthetic Detergents.
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19.   Bord, R. S. A Study of Sludge Handling and Disposal.
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20.   Brooks. R. J. and B. J.  Use of Stabilized Sulfur
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21.   Brooks, R. J.  Improved Process for Sulfonation  Using
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22.   Bureau of the Census.   1967 census of Manufactures.
     Concentration Ratios in Manufacturing, Part  3;   Emiploy-
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23.   California Water Quality Control Board.  Detergent
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24.   ARCO chemical Company.  Description of Process  for
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25.   Chemical Engineers Handbook.  McGraw Hill Company.
     4th  Edition.    (1963)
                                190

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i!»5.   Chemiton Corp.  Oleum Sulfonation Process Equipment.
     Brochure.  Seattle Washington.   (1968)

27.   Chemithon Corp.  S03 Detergent Process Equipment.
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28.   Chemical Week.  197^3 Buyers1 Guide Issue.  McGraw
     Hill.  October 25  (1972)

29.   cross, C. F. and Dreyfuc, C.  Low Temperature  Catalytic
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30.   Cutler and Davis.  Deterqentry,  Theory and Test  Methods.
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32.  Davidson, A.  Detergents Powders via  New Process.
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                                 191

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                               192

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56.  Mills, V.  Continuous Countercurrent Hydrolysis of Fats.
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                               193

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                                 194

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                           SECTION XIV

                            GLOSSARY
ABS - An abbreviation applied to a family of closely related
branched side-chain benzene compounds formerly used as sur-
factants in household detergents.  ABS is an acronym for al-
kyl benzene sulfonate.

Act - The Federal Water Pollution Control Act Amendments
of 1972, Public Law 92-500.

Aerobic - Growing only in air or free oxygen.

Aerobic Bacteria - Bacteria  which require the presence of
free  (dissolved or molecular) oxygen for their metabolic
processes.  Oxygen in chemical combination will not support
aerobic organisms.

Alkalinity - A quantitative measure of the capacity of li-
quids or suspensions to neutralize strong acids or to re-
sist the establishment of acidic conditions.  Alkalinity
results from the presence of bicarbonates, carbonates,
hydroxides, volatile acids, salts and occasionally borates,
terms of the concentration of calcium carbonate that would
have an equivalent capacity to neutralize strong acids.

Amalgamator - A large horizontal mixer used to blend per-
fume, dyes, fillers (titanium dioxide for whitening), and
other materials in the manufacture of soap.

Anaerobic Bacteria - Bacteria that do not require the pres-
ence of free or dissolved oxygen for metabolism.  Strict
anaerobes are hindered or completely blocked by the presence
of dissolved oxygen and in some cases by the presence of
highly oxidized substances such as sodium nitrate, nitrites,
and perhaps sulfates.   Facultative anaerobes can be active in
the presence of dissolved oxygen but do not require its
presence,  see also aerobic bacteria.

Anaerobic Decomposition - Reduction of the net energy level
and change in chemical composition of organic matter caused
by microorganisms in an  anaerobic environment.

Antioxidants - Phenolic and amino compounds which inhibit
oxidation of organic compounds.

Atmosphere - Unit of pressure.  One atmosphere is normal
atmosphere pressure.
                                195

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Barometric Condenser - A system of both chilling vapors
into the liquid state from a gaseous state and reducing
flowing down a vertical pipe with considerable velocity.
Identical to the laboratory aspirator, which depends upon
the Venturi effect to create a vacuum.

Battery Limits - In considering plant construction and
costs, an arbitrary boundary between essential process
units and supporting facilities.  Customarily within bat-
tery limits are reactors, stills, mixers, driers, and
fabricators.  Usually outside battery limits are power
plants, cooling towers, sewage and water treatment, raw
material and product storage, laboratory and office buildings
and roads.

Best Available Demonstrated^ Control Technology (BADCTL -
Treatment required for new sources as defined by Section
306  (a) (2) of the Act.  Level III.

Treatment required by July 1, 1983 for industrial discharges
to surface waters as defined by Section 301 (b)  (2)  (A) of
the Act.  Level II.

Best Practicable Control Technology Currently Available
(BPCTCA) ~ Treatment required by July 1, 1977 for industrial
discharges to surface waters as defined by Section 301  (b)
(1)  (A) of the Act.

Biological Cooling Tower - A cooling tower which is seeded
with microorganisms and fed with nutrients in which biological
degradation of organics occurs.

Biological Oxidation - The process whereby, through the
activity of living organisms in an aerobic environment,
organic matter is converted to more biologically stable
matter.

Biological Stabilization - Reduction in the net energy level
of organic matter as a result of the metabolic activity of
organisms.

Biological Treatment - Organic waste treatment in which bac-
teria and/or biochemical action is intensified under con-
trolled conditions.

Blowing^Tower - See spray tower.
                               196

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BOD5 - Biochemical oxygen demand.  An indirect measure of the
concentration of biologically degradable material present in
organic wastes.  It is the amount of free oxygen utilized by
aerobic organisms when allowed to attack the organic matter
in an aerobically maintained environment at a specified
temperature  (20°C) for a specific time period (five days).
It is expressed in milligrams of oxygen utilized per liter
of liquid waste volume  (mg/1) or in milligrams of oxygen per
kilogram of solids present (mg/kg=ppm=parts per million parts)

Builders - Inorganic salts (usually) which augment the
cleansing or dirt-suspending power of a soap or detergent;
i.e., sodium silicate, sodium carbonate, carboxy methyl
cellulose, phosphates, etc.

Capital Costs - Financial charges which are computed as the
control.  The cost of capital is based upon a weighted aver-
age of the separate costs of debt and equity.

Caustic - Sodium hydroxide, caustic soda.

Changes - Those separate and identifiable steps taken in the
manufacture of kettle boiling soap.

Chemical Oxidation - Oxidation of organic substances without
benefit of livingTorganisms.   Examples are by thermal combus-
tion or by oxidizing agents such as chlorine.

Clay - Alumino silicate minerals.

Closed Soap - That single phase of soap and water having a
creamy consistency while in the hot, agitated state.

COD - Chemical Oxygen Demand.  An indirect measure of the
biochemical load exerted on the oxygen assets of a body of
water when organic wastes are introduced into the water.

Cold Frame soap - A type of soap produced by solidification
by cooling and slicing into bars.

Condensate - The product resulting from a vapor condensing.

Cooling Water Slowdown - Whenever cooling water is reused
and run over atmospheric contactors (in turn cooled by am-
bient air)  there is a buildup of contaminants.  Periodically
it is necessary to dilute them or treat the cooling water to
"blow down" or rid the system of the concentrated contaminants.
                              197

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           & cylindrical vessel of 681 - 2270 kg (1500 -
5000 Ib) capacity in which soap or synthetic surfactants
are mixed with builders prior to drying.  It is often steam
jacketed.

De-aerator - A piece of equipment for removing air dissolved
or suspended in a fluid.

Detergent - Technically, any cleaning agent, including ordi-
nary soap, the new "synthetic" granules and liquids, many
alkaline materials, solvent, or even sand when used for
scrubbing, whether used in the home or in industry.  In
popular speech, the term "detergent" is generally applied
to packaged cleaning products based on a surface active
ingredient such as ABS or LAS.  Its cleaning power is re-
tained in hard water, contrary to the performance of soap.

Dissolved Oxygen - The oxygen dissolved in sewage,  water,
or other liquid, usually expressed as milligrams per liter
or as per cent of saturation.

Effluent - The outflow of a sewer; a waste waterstream from
a manufacturing process or plant.

EyaEprator - A unit in which liquids are converted to gas.

Fat - Glycerol esters of long chain fatty acids of animal
or vegetable origin.

Fat Refining - Purification of fats by treatment with clay,
caustic, etc.

Fat ^Splitting - Various processes for hydrolysis of fatty
triglycerides to fatty acids and glycerine.

Fatty Acid - Naturally occurring straight chain carboxylic
acids which usually occur as triglyceride esters (fats).

Fatty Oil - Triglycerides which are liquid at room temperature.

£it£i£2_£3;i§G2§ ~ Also called pitching or finishing change,
is the final step in soap making in which clear water is
mixed with the soap to separate the neat soap from the
nigre.

Foots - The residue of refining fats or oils which contain
color bodies, insolubles, suspended matter, etc.

Full Boil^Process - Soap making where the neat soap is com-
pleted in the kettle and the by-product glycerine drawn off.
                                198

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.Heels - The residue remaining from any processing unit
after drawing.

Killing Change - The first step in soap manufacture where
fresh fat is brought into contact with a lye solution.
The start of the saponification process.

LAS - A new surfactant in which a straight chain hydro-
carbon has been joined to the benzene ring.  It has a high
rate of biodegradability.

Low Grade Fatty Acids - These are contaminated fatty acids
derived from recovery of scrap, acidification of nigre, and
contaminated fatty acid raw materials.

Mazzonj Process - A proprietary process for manufacture of
soap.

rng/l - Milligrams per liter.

Neat Soap - An intermediate, completely saponified and puri-
fied soap containing about 20 - 30 percent water, ready for final
formulation into finished product.

New Source - Any building, structure, facility or installa-
tion from which there is or may be a discharge of pollutants
and whose construction is commenced after the publication of
the guidelines.

Nigre - The bottom layer which separates out in the last wash-
ing step of kettle boiling soap which contains the impurities
leading to poor color, odor, etc.  Often contains 20 - 25 percent of
the kettle contents at that stage of the soap making and
possesses a soap content of 30 - 40 percent.  The nigre can be
concentrated and salted out to yield a low grade colored
soap for sale.

No Discharge of Pollutants - No net increase (or detectable
gross concentration if the situation dictates)  of any para-
meter designated as a pollutant to the accuracy that can be
determined from the designated analytical methods.

Oil - Fats found in liquid form at room temperature. Gly-
cerol esters of long chain fatty acids.

Oleum - A solution of SO3_ in sulfuric acid.

Operations and Maintenance Costs - Those required to operate
and maintain pollution abatement equipment.  They include
labor,  material, insurance, taxes, solid waste disposal, etc.
                               199

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JDH - a measure of the relative acidity or alkalinity of
water.  A pH of 7.0 indicates a neutral condition.  A
greater pH indicates alkalinity and a lower pH indicates
acidity.  A one unit change in pH indicates a tenfold change
in acidity and alkalinity.

Phenol - Class of cyclic organic derivatives with the basic
formula C6H5OH.

Pjl odder - A powerful homogenizer which resembles a sausage
grinder in design; used for the final processing of bar
soap wherein the occluded air is removed (under partial
vacuum) and the individual soap particles melded into one
continuous homogenous whole prior to being cut up into bar
stock.

Polj.ution - The presence in a body of water (or soil or air)
of substances of such character and in such quantities that
the natural quality of the body of water (or soil or air) is
degraded to a point where the water is rendered useless or
offensive to the senses of sight, taste or smell.  Contami-
nation may accompany pollution.  In general, a public health
hazard is created, but in some cases only economy or esthetics
are involved as when waste salt brines contaminate surface
waters or when foul odors pollute the air.

Pretreatment - Treatment provided prior to discharge to a
publicly owned treatment works.

Process Water - In the manufacture of soap and detergent,
all waters that come into direct contact with the raw mater-
ials, intermediate products, final products or contaminated
waters or air.

Refractory BOD5- Organic substances which are slowly or
incompletely degraded by microorganisms.

Saponification - The hydrolysis of an ester into its
corresponding alcohol and soap.

Secondary Treatment - Biological treatment provided beyond
primary clarification, usually aerobic activated sludge,
trickling filters or lagoon systems.

Semi-boil Process - That soap making process wherein the
exact  (stoichiometric) amount of caustic is added to fat
for saponification, and the soap is then run off into frames
or further processed without the benefit of removal of by-
product glycerine.
                              ZUO

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Sewage - Water after it has been fouled by various uses.
From the standpoint of source it may be a combination of
the liquid or water-carried wastes from residences, office
buildings and institutions together with those from indus-
trial and agricultural establishments, and with such ground-
water, surface water and storm water as may be present.

Sewer Lyes - Waste sodium hydroxide from reclaiming of scrap
soap.

Silicates - A chemical compound containing silicon, oxygen,
and one or more metals.  In soaps and detergents, sodium
silicates are added to provide alkalinity and corrosion
protection.

Soap Boiling - The process of heating a mixture of fats/oils
with caustic solution until the fatty ester is split and
the alkaline metal salt formed, glycerine being released in
the process.  The step where saponification takes place.

Soda Ash - Sodium carbonate.

Spray Drying Tower - A large vessel in which solids in
solution or suspension are dried by falling through hot gas.

Stabilizgrg - An additive which gives physical and/or
chemical stability to a formulation.

Still - A distillation apparatus.

Strong Change - That step in the soap making process where
virgin, strong lye is added to the already saponified fat
to finally complete saponification of remnants of fat.

Surface Waters - Navigable waters; the waters of the U.S.
including the territorial seas.

Sweet Water - By-product aqueous glycerine from soap manu-
facture.

Synthetic Detergent - chemically tailored cleaning agents
soluble in water or other solvents.  Originally developed
as soap substitutes.  Because they do not form insoluble
precipitates, they are especially valuable in hard water.
They are generally combinations of surface active agents
and complex phosphates to enhance detergency.

TDS - Total dissolved solids.
                              201

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