EPA 440/1-74/022
          DEVELOPMENT DOCUMENT  FOR
   PROPOSED EFFLUENT LIMITATIONS GUIDELINES
   AND NEW SOURCE  PERFORMANCE  STANDARDS
                    FOR  THE
               TEXTILE  MILLS
               POINT SOURCE CATEGORY
                    ^ 	
                   &  ^m  •£
                            LU
          UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
                    JANUARY 1974

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              DEVELOPMENT DOCUMENT

                      for

    PROPOSED EFFLUENT LIMITATIONS GUIDELINES

                      and

        NEW SOURCE PERFORMANCE STANDARDS

                    for the

                 TEXTILE MILLS

             POINT SOURCE CATEGORY
                 Russell Train
                 Administrator

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

                James D. Gallup
                Project Officer
                  January 1974

          Effluent Guidelines Division
        Office of Air and Water Programs
      U.S. Environmental Protection Agency
            Washington, D.C.  20460
             U.S. Environmental r-yfcection
             ->.-lion 5, Library t^L-^
              «."0 S. Dearborn          ••

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                                ABSTRACT

This  document  presents  the  findings  of  a  study  of  the   textile
manufacturing  industry  for  the  purpose  of  developing  waste  water
effluent limitation guidelines and Federal standards of performance  for
new  sources in order to implement Section 304 (b)  and 306 of the Federal
Water Pollution Control Act Amendments of 1972 (the "Act").   This  study
covers approximately 7,000 plants in S.I.C. 22.

Effluent limitations guidelines are set forth for the degree of effluent
reduction  attainable  through  the application of the "Best Practicable
Control  Technology  Currently  Available",  and  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"  set forth the degree of
effluent reduction which is achievable through the  application  of  the
best  available  demonstrated  control  technology,  processes, or other
alternatives.

The proposed regulations  for  July  1,  1977,  require  in-plant  waste
management  and  operating  methods,  together  with  the best secondary
biological treatment technology currently available for  discharge  into
navigable  water  bodies.  This technology is represented by preliminary
screening, primary treatment  (wool scouring only),  coagulation   (carpet
mills only), and secondary biological treatment.

The  recommended  technology  for  July  1,  1983,  and  for  new source
performance standards, is  in-plant  waste  management  and  preliminary
screening,  coagulation  (carpet mills only), primary sedimentation (wool
scouring only) , biological secondary treatment  and  advanced  treatment
such as multi-media filtration or activated carbon adsorption.

Supportive  data  and rationale for development of the proposed effluent
limitation guidelines and standards of performance are contained in this
report.

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                                 CONTENTS


Section                                                             Pa%

I              CONCLUSIONS                                           1

II             RECOMMENDATIONS                                       3

III            INTRODUCTION                                          7

                 Purpose and Authority                               7
                 Methodology                                         8
                 General Description of the Industry                 9
                 Profile of Manufacturing Processes                 17
                   Wool Fiber and Fabric Finishing Operations       17
                   Cotton Fiber and Fabric Finishing Operations     19
                   Synthetic Fiber and Fabric Finishing Operations  21
                   Process Description by Subcategory               22

IV             INDUSTRY CATEGORIZATION                              33

                 Previous Approaches                                33
                 Categorization                                     35
                   Economic Considerations                          42

V              WASTE CHARACTERISTICS                                46

                 Subcategory 1 - Raw Wool Scouring                  46
                 Subcategory 2 - Wool Finishing                     48
                 Subcategory 3 - Greige Mills                       51
                 Subcategory 4 - Woven Fabric Finishing             52
                 Subcategory 5 - Knit Fabric Finishing              63
                 Subcategory 6 - Carpet Mills                       64
                 Subcategory 7 - Yarn Dyeing and Finishing          65

VI             SELECTION OF POLLUTANT PARAMETERS                    66

                 Waste Water Parameters of Major Significance       66
                                    iii

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                           CONTENTS (Continued)
Section
VI
VII
VIII
  Rationale for Selection of Major Parameters         66
    Biochemical Oxygen Demand                         66
    Suspended Solids                                  67
    pH                                                67
    Chemical Oxygen Demand                            67
    Fecal Coliforms                                   67
    Grease and Oil                                    68
  Rationale for Selection of Minor Parameters         68
    Total Dissolved Solids                            68
    Alkalinity                                        68
    Ammonia Nitrogen and Other Nitrogen Forms         68
    Phosphates                                        68
    Temperature                                       69
    Color                                             69
    Chromium                                          69
    Other Heavy Metals                                69
    Phenols                                           70
    Sulfides                                          70
    Toxic Organic Chemicals                           70

CONTROL AND TREATMENT TECHNOLOGY                      72

  In-Process Control                                  72
  New Process Technology                              75
  Specific In-Process Changes                         78
  Biological Treatment Technology                     79
  Performance of Biological Treatment Systems         87
  Advanced Waste Water Treatment Technology           91

COST, ENERGY, AND NON-WATER QUALITY ASPECTS          112

  Cost and Reduction Benefits of Alternative         112
    Treatment and Control Technologies

  Basis of Economic Analysis                         112

  Cost Effectiveness of Treatment Alternatives       126

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                           CONTENTS (Continued)
Section
VIII
IX
  Impact of Waste Treatment Alternatives on
    Finished Product

  Alternative Treatment Systems

  Electrical Energy Requirements

  Thermal Energy Requirements

  Solid Wastes

EFFLUENT REDUCTION ATTAINABLE THROUGH THE
  APPLICATION OF THE BEST PRACTICABLE CONTROL
  TECHNOLOGY CURRENTLY AVAILABLE EFFLUENT
  LIMITATIONS GUIDELINES

  Introduction
  Effluent Reduction Attainable Through the
    Application of Best Practicable Control
    Technology Currently Available

  Identification of Best Practicable Control
    Technology Currently Available

Rationale for the Selection of Best Practicable
  Control Technology Currently Available

Age and Size of Equipment and Facility

Total Cost of Application in Relation to
  Effluent Reduction Benefits

Engineering Aspects of Control Technique
  Applications

Process Changes

Non-Water Quality Environmental Impact

Factors to be Considered in Applying Level I
  Guidelines
Page

 127


 142

 142

 142

 143

 144
                                                                     144
                                                                     145
                                                                     149


                                                                     160


                                                                     160

                                                                     160


                                                                     161


                                                                     161

                                                                     161

                                                                     161

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                           CONTENTS (Continued)
Section                                                             Page
X              EFFLUENT REDUCTION ATTAINABLE THROUGH THE             162
                 APPLICATION OF THE BEST AVAILABLE TECHNOLOGY
                 ECONOMICALLY ACHIEVABLE EFFLUENT LIMITATIONS
                 GUIDELINES

                 Introduction                                        162

                 Effluent Reduction Attainable Through               163
                   Application of the Best Available Technology
                   Economically Achievable

                 Identification of the Best Available                163
                   Technology Economically Achievable

                 Rationale for the Selection of Best Available       165
                   Control Technology Economically Achievable

                 Age and Size of Equipment and Facilities            165

                 Total Cost of Application in Relation to            165
                   Effluent Reduction Benefits

                 Engineering Aspects of Control Technique            165
                   Application

                 Process Changes                                     166

                 Non-Water Quality Environmental Impact              166

                 Factors to be Considered in Applying Level          166
                   II Guidelines

XI             NEW SOURCE PERFORMANCE STANDARDS                      168

                 Introduction                                        168

                 Effluent Reduction Attainable for New Sources       168

                 Pretreatment Requirements                           169
                                     vi

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                            CONTENTS (Continued)
Section
Page
XII            ACKNOWLEDGEMENTS                                      170




XIII           REFERENCES                                            172




XIV            GLOSSARY                                              198




XV             CONVERSION TABLE                                      205
                                    vii

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                                  TABLES
Number                                                              Page

1              Maximum Thirty Day Average Recommended                  4
               Effluent Limitation Guidelines for July 1, 1977

2              Maximum Thirty Day Average Recommended                  5
               Effluent Limitation Guidelines for July 1, 1983

3              Number of Textile Plants by Geographic Areas:          11
               1967

4              Water Use by the Textile Industry                      15

5              Water Discharged by the Textile Industry               16

6              Industry Categorization                                34

7              Basis for Size Exception within Textile                44
               Subcategorization

8              Types and Amounts of Dyes Used in the Textile          58
               Industry

9              Chemicals Used in Application of Dyes                  61

10             Expected Effluent Suspended Solids from Multi-         95
               Media Filtration of Biological Effluents

11             Carbon Adsorption Pilot Plant:  Average Water         104
               Quality Characteristics

12             Accuracy of Standardized Costing Methodology          116

13             Waste Water Treatment Costs for Subcategory           129
               l-(Small)

14             Waste Water Treatment Costs for Subcategory           130
               1-(Medium)
                                     ix

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Number                                                              Page

15             Waste Water Treatment Costs for Subcategory           131
               2-(Small)

16             Waste Water Treatment Costs for Subcategory           132
               2-(Medium)

17             Waste Water Treatment Costs for Subcategory           133
               3-(Average)

18             Waste Water Treatment Costs for Subcategory           134
               4-(Small)

19             Waste Water Treatment Costs for Subcategory           135
               4-(Medium)

20             Waste Water Treatment Costs for Subcategory           136
               5-(Small)

21             Waste Water Treatment Costs for Subcategory           137
               5-(Medium)

22             Waste Water Treatment Costs for Subcategory           138
               6-(Small)

23             Waste Water Treatment Costs for Subcategory           139
               6-(Medium)

24             Waste Water Treatment Costs for Subcategory           140
               7-(Small)

25             Waste Water Treatment Costs for Subcategory           141
               7-(Medium)

26             Maximum Thirty Day Average Recommended Effluent       146
               Limitations Guidelines for July 1, 1977

27             Performance of Biological Treatment Systems           148

28             Performance of Effluent Treatment Systems             150
               Subcategory 1:  Wool Scouring

29             Performance of Effluent Treatment Systems             155
               Subcategory 4:  Woven Fabric Finishing
                                     x

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Number                                                              Page

30             Performance of Effluent Treatment Systems             156
               Subcategory 5:  Knit Fabric Finishing

31             Performance of Effluent Treatment Systems             158
               Subcategory 6:  Carpet Mills

32             Performance of Effluent Treatment Systems             159
               Subcategory 7:  Stock and Yarn Dyeing

33             Maximum Thirty Day Average Recommended                164
               Effluent Limitations Guidelines for July 1, 1983
                                     XI

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                                  FIGURES


Number                             Title                            Page

1           Subcategory 1:  Wool Scouring                             23

2           Subcategory 2:  Wool Finishing                            24

3           Subcategory 3:  Greige Mills                              28

4           Subcategory 4:  Woven Fabric Finish                       29

5           Subcategory 5:  Knit Fabric Finishing                     30

6           Subcategory 6:  Carpet Mills                              31

7           Subcategory 7:  Stock and Yarn Dyeing and Finishing       32

8           COD Isotherms Using Virgin Carbon and Different          102
            Secondary Sewage Effluent

9           Schematic of an Activated Carbon System                  103
            Including Thermal Regeneration

10          Aerated Stabilization Basin Construction Cost            117

11          Engineering Costs                                        118

12          Clarifier Capital Cost                                   119

13          Aerated Stabilization Basin (Aeration Equipment Only)    120

14          Aerated Stabilization Basin Annual Operation and         121
            Maintenance Labor

15          Aerated Stabilization Basin (Material and Supply         122
            Costs, Annual) (Chemical Costs)

16          Aeration Equipment Annual Power Costs (Aerated           123
            Stabilization Basin)

17          Clarifier, Annual Operation and Maintenance Labor        124
                                   xii

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Number                             Title                            Page

18          Clarifier (Material and Supply Costs, Annual)            125
            (Major Chemical Costs)

19          Typical Seasonal Variation for Biological                147
            Treatment

20          Distribution of Water Use for Greige Mills               153
                                  xiii

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                               SECTION I

                              CONCLUSIONS

The purpose  of  this  report  is  to  establish  waste  water  effluent
limitation   guidelines  for  the  textile  manufacturing  industry.    A
conclusion  of  this  study  is  that  this  industry  comprises   seven
subcateaories:

    1.   Wool Scouring
    2.   Wool Finishing
    3.   Greige Mills
    4.   Woven Fabric Finishing
    5.   Knit Fabric Finishing
    6.   Carpet Mills
    7.   Stock and Yarn Dyeing and Finishing

The  major  criteria  for the establishment of the subcategories are the
biochemical oxygen demand (BOD5) ,  chemical  oxygen  demand   (COD) ,  and
total    suspended    solids   (TSS)   in   the   plant   waste   water.
Subcategorizaticn is required on the basis of the raw material.used  and
the  production  process employed.  Evaluation of such -factors as age of
facilities, location and climate and similarities in available treatment
and  control  measures  substantiate  this  industry  subcategorization.
However,   the   facility's   size  required  an  exception  within  the
subcategorization.  Different limitations were  established  for  plants
within  six  subcategories  due  to  unequal economic impacts created by
diseconomies of scale.

The wastes from all subcategories are amenable to  biological  treatment
processes and at least eighteen textile manufacturing plants are able to
achieve  high  levels  of  effluent  reduction  (BODS and total suspended
solids) through secondary biological treatment systems.   These  systems
treat  waste  waters  from  dyeing  and  finishing broadwoven cotton and
cotton synthetic blends, knits and stock and yarn.  It is estimated that
the costs for all  plants  within  the  industry  to  achieve  the  best
practicable  effluent  reduction  would  result  in  final product price
increases ranging from 0.1 cents per kilogram  product   (0.2  cents  per
pound  product)  to  a  high  of  0.8  cents per kilogram (1.8 cents per
pound).  The average price increase is less than 0.4 cents per  kilogram
 (0.9 cents per pound).

The  cost  of  achieving  the  best  available  effluent  limitations is
estimated to result in further final  product  price  increases  ranging
from 0.05 to 0.4 cents per kilogram  (0.1 to 0.8 cents per pound) product
processed for all greige mills and for all small plants in the other six
subcategories.   Cost  increases  are  expected to range from 0.4 to 2.0

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cents per kilogram (0.8 to 4.5 cents per pound)  for larger plants in the
industry subcategories  (except greige mills) .

The estimated final product costs required to  achieve  best  practicable
and  best  available effluent reductions range between 0.3 and 1.1 cents
per kilogram (0.6 and 2.5 cents per pound)  for small plants and  0.5  to
2.5 cents per kilogram  (1.0 and 5.4 cents per  pound)  for larger plants.

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                               SECTION II

                            RECOMMENDATIONS

The  waste  water  effluent reduction limitations attainable through the
application  of  the  best  practicable  control  technology   currently
available   are   based  on  the  performances  of  exemplary  secondary
biological systems treating textile  manufacturing  waste  water.    Best
practicable   control   technology   currently  available  includes  the
following   treatment   components:   preliminary   screening,    primary
sedimentation  (wool scouring only) , coagulation (carpet mills only) , and
secondary biological treatment.

The  waste  water  effluent reduction limitations attainable through the
application  of  the  best  available  control  technology  economically
achievable  are  based  on  the best practicable control technology plus
advanced treatment including multi-media filtration for greige  mills and
small textile mills in the remaining  six  subcategories  and  activated
carbon  adsorption  for  larger  mills  in  the six subcategories.   Both
filtration and carbon absorption may be needed where large quantities of
dispersed  dyes  or  materials  with  poor   adsorptive   capacity    are
discharged.

Recommended best practicable effluent limitations to be achieved by July
I,  1977,  are  set  forth  in  Table  1  and recommended best  available
limitations to be achieved by July 1, 1983, are set forth  in  Table  2.
These  limitations  are  the  average  of daily values for any  period of
thirty consecutive days.  Maximum limitations for any one day for  BOD5,
TSS,  COD  and  oils  and  grease  should  not  exceed  these thirty day
limitations by more than one hundred percent.

The waste water effluent reduction limitations for new sources   are  the
same  as  those attainable through the application of the best  available
control  technology  economically  achievable.   These  limitations  are
possible  because  of  the  present  availability  of  the treatment and
control technology to attain this level of effluent reduction.

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                                    TABLE   1

                         MAXIMUM THIRTY DAY AVERAGE
                       RECOMMENDED EFFLUENT LIMITATION
                         GUIDELINES FOR JULY 1, 1977

                                           Effluent Limitations (1)

                                    BODS              TSS              ODD
                                  kg/lOOOkg        kg/lOOOkg         kg/lOOOkg
Plant Subcategory                (Ib/lOOOlb)      (Ib/lOOOlb)       (Ib/lOOOlb)

1.  WDOL SCOURING (2)
    Plant capacity less than         3.7              3.7               NA
     6,500 kg/day (14,300 Ib/day)
    Plant capacity greater than      3.7              3.7               24
     6,500 kg/day (14,300 Ib/day)

2.  WOOL FINISHING
    Plant capacity less than         7.5              7.5               NA
     900 kg/day (1,980 Ib/day)
    Plant capacity greater than      7.5              7.5               56
     900 kg/day (1,980 Ib/day)

3.  GREIGE MILLS
    All plant sizes                  0.45             0.45

4.  W3VEN FABRIC FINISHING
    Plant capacity less than         2.2              6.9               NA
     1,000 kg/day (2,200 Ib/day)
    Plant capacity greater than      2.2              6.9               33
     1,000 kg/day (2,200 Ib/day)

5.  KNIT FABRIC FINISHING
    Plant capacity less than         1.8              8.0               NA
     3,450 kg/day (7,590 Ib/day)
    Plant capacity greater than      1.8              8.0               24
     3,450 kg/day (7,590 Ib/day)

6.  CARPET MILLS
    Plant capacity less than         4.3              4.3               NA
     3,450 kg/day (7,590 Ib/day)
    Plant capacity greater than      4.3              4.3               30
     3,450 kg/day (7,590 Ib/day)

7.  STOCK AND YARN DYEING AND FINISH-
    ING
    Plant capacity less than         3.5              9.2               NA
     3,100 kg/day (6,820 Ib/day)
    Plant capacity greater than      3.5              9.2               47
     3,100 kg/day (6,820 Ib/day)

                               NA MEANS NOT APPLICABLE

(1)  Plant capacities and discharge limitations are stated for Subcategories
     1 and 2 per weight of raw wool received at the wool scouring or wool
     finishing operation and are stated for Subcategories 3, 4, 5, 6 and 7
     per weight of final material produced by the facility.

     For all Subcategories pH should range between 6.0 to 9.0 at any time.

     For all Subcategories Most Probable Number (MPN) of Fecal Coliforms
     should not exceed 400 counts per 100 ml.

(2)  For all Wool Scouring plants  (Subcategory 1)  Oils and Grease should
     not exceed 1.9 kg (lb)/1000 kg (Ib) grease wool.

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                                    TABLE   2

                         -MAXIMUM THIRTY DAY AVERAGE
                       RECOMMENDED EFFLUENT LIMITATION
                         GUIDELINES FOR JULY 1, 1983


                                           Effluent Limitations  (1)

                                    BODS              TSS              COD
                                  kg/lOOOkg        kg/lOOOkg -        kg/lOOOkg
Plant Subcategory                 (Ib/lOOOIb)       (Ib/lOOOlb)        (Ib/lOOOlb)

1.  WOOL SCOURING  (2)
    Plant capacity less than         2.5              2.5               NA
     6,500 kg/day  (14,300 Ib/day)
    Plant capacity greater than      2.5              2.5               64
     6,500 kg/day  (14,300 Ib/day)

2.  WOOL FINISHING
    Plant capacity less than         5.0              5.0               NA
     900 kg/day  (1,980 Ib/day)
    Plant capacity greater than      5.0              5.0               14.9
     900 kg/day  (1,980 Ib/day)

3.  GREIGE MILLS
    All plant sizes                  0.3              0.3               NA

4.  WOVEN FABRIC FINISHING
    Plant capacity less than         1.5              4.6               NA
     1,000 kg/day  (2,200 Ib/day)
    Plant capacity greater than      1.5              4.6                8.8
     1,000 kg/day  (2,200 Ib/day)

5.  KNIT FABRIC FINISHING
    Plant capacity less than         1.2              5.3               NA
     3,450 kg/day  (7,590 Ib/day)
    Plant capacity greater than      1.2              5.3                6.4
     3,450 kg/day  (7,590 Ib/day)

6.  CARPET MILLS
    Plant capacity less than         2.9              2.9               NA
     3,450 kg/day (7,590 Ib/day)
    Plant capacity greater than      2.9                                 8.0
     3,450 kg/day (7,590 Ib/day)

7.  STOCK AND YARN DYEING AND FINISH-
    ING
    Plant capacity less than         2.3              6.1               NA
     3,100 kg/day (6,820 Ib/day)
    Plant capacity greater than      2.3              6.1               12.5
     3,100 kg/day (6,820 Ib/day)

                               NA MEANS NOT APPLICABLE

(1)   Plant capacities and discharge limitations are stated for Subcategories
     1 and 2 per weight of raw wool received at the wool scouring or wool
     finishing operation and are stated for Subcategories 3, 4, 5, 6 and 7
     per weight of final material produced by the facility.

     For all Subcategories pH should range between 6.0 to 9.0 at any tima.

     For all Subcategories Most Probable Number (MPN)  of Fecal Coliforms
     should not exceed 400 counts per 100 ml.

(2)   For all Wool Scouring plants (Subcategory 1)  Oils and Grease should
     not exceed 1.9 kg (lb)/1000 kg (Ib)  grease wool.

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                              SECTION III

                              INTRODUCTION


                         Purpose and Authority

Section 301(b)  of the Act requires the achievement, by  not  later  than
July  1,  1977,  of  effluent  limitations for point sources, other than
publicly owned treatment works, which are based on  the  application  of
the  best  practicable control technology currently available as defined
by the Administrator pursuant to Section 304(b)   of  the  Act.   section
301(b) also requires the achievement, by not later than July 1, 1983, of
effluent  limitations  for  point  sources,  other  than  publicly owned
treatment works,  which  are  based  on  the  application  of  the  best
available  technology  economically  achievable  which  will  result  in
reasonable further progress toward the national goal of eliminating  the
discharge   of   all   pollutants,  as  determined  in  accordance  with
regulations issued by the Administrator pursuant to  Section  305(b)   to
the Act.  Section 306 of the Act requires the achievement by new sources
of  a  Federal  standard of performance providing for the control of the
discharge of pollutants which reflects the greatest degree  of  effluent
reduction  which  the  Administrator determines to be achievable through
the application of the best available demonstrated  control  technology,
processes,  operating  methods,  or other alternatives, including, where
practicable, a standard permitting no discharge of pollutants.

Section 304(b)  of the Act requires the Administrator to  publish  within
one  year  of enactment of the Act, regulations providing guidelines for
effluent 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 achievable including treatment techniques, process and  proce-
dure  innovations,  operation methods and other alternatives.  The regu-
lations  proposed  herein  set  forth  effluent  limitations  guidelines
pursuant  to  Section  304 (b)  of  the Act for the textile manufacturing
source category.

Section 306 of the Act requires the Administrator, within one year after
a category of sources is included in a list published pursuant  to  Sec-
tion  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  textile  manufacturing source
category, which was included within the list published January 16, 1973.

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The effluent limitations guidelines and standards  of  performance  pro-
posed  herein  were  developed  in  the  following  manner.   The textile
industry was first categorized for the purpose  of  determining  whether
separate  limitations  and  standards  are appropriate for its different
segments.   Considerations  in  the  industry   categorization   process
included  raw  materials,  the  products, manufacturing procass, and raw
waste characteristics.

The raw waste  characteristics  for  each  subcategory  were  identified
through  analyses  of:   (1)   the  sources and volumes of water and waste
waters and  (2)  the constituents  of all waste waters including toxic  or
hazardous  constituents  and  other  constituents which result in taste,
odor or color.   The constituents of waste waters that 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  were  identified.  This included an identification of
each distinct control and treatment technology,  including both  in-plant
and  end-of-process technologies, which are existent or capable of being
designed for each subcategory.  It also included an  identification,  in
terms  of  the  amount  of constituents  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 treat-
ment and control technology and the required  implementation  time  were
also  identified.   The non-water quality environmental impact were also
identified, e.g., ths effects of the application  of  such  technologies
upon  other  pollution  problems, including air, solid waste, noise, and
radiation.  The energy requirements of each of the control and treatment
technologies were identified as well as the cost of the  application  of
such technologies.

The information, as outlined above, was then evaluated to determine what
levels of technology constituted the "best practicable control technolo-
gy   currently   available,"  "best  available  technology  economically
achievable"  and  "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),  the  treatability  of  the wastes, and water use
practices.

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The data for the identification and analyses were derived from a  number
of  sources.  These sources included EPA research information, published
literature, previous EPA technical  guidance  for  textile  manufacture,
various industry associations, qualified technical consultation, and on-
site  visits and interviews at exemplary textile manufacturing plants in
the United States.  All references used in developing the guidelines for
effluent limitations  and  standards  of  performance  for  new  sources
reported herein are listed in Chapter XIV.

§enera1_Description of the^Industry

Since  1638,  when  the  first  commercial  mill was erected at Raleigh,
Massachusetts, the U.S. textile industry has burgeoned to a point  where
there  are  nearly 7100 plants in 47 states, employing about one million
people, and in 1972 selling goods valued  at  just  under  $28  billion.
These  plants  range from highly integrated manufacturing complexes that
process basic raw  materials  into  finished  products,  to  small  non-
integrated contract plants that process goods owned by other producers.

According to the  1967 census of Manufacturers, the textile industry, SIC
Code 22, contains ten major SIC classifications.  In recent decades, the
industry  has  been  concentrating  in  the  southeast--notably  in  the
Carolinas, Georgia and Alabama—and this trend is continuing.   Today  38
percent of the textile plants are in the southeast and 92 percent are on
the  eastern  seaboard.   The  rest,  as  shown in Table 3 are scattered
throughout the  country.   Knitting  mills,  with  almost  2,700  plants
listed,  constitute  the  largest  group  but there are also about 1,000
weaving mills of various types  and  over  1,000  plants  which  process
miscellaneous  textile goods.  Most of the textile industry is contained
within EPA Regions 1, 2, 3 and 4, with Region 4 accounting for  a  major
proportion  of  the  industry.  As shown below, almost 80 percent of the
industry is located in the southern and mid-atlantic states.

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South                                 2656              38



Mid-Atlantic                          2821              40



New England                            978              14



North Central                          321               4



West                                  _3.04              _4



                                      7080             100



Source:  1967 Census of Manufacturers
                                10

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The industry's basic  raw  materials  are  wool,  cotton,  and  man-made
fibers.  Of the roughly 5.0 billion kilograms (11 billion pounds)  of raw
materials  consumed  by  the  industry in 1972,  wool computed on a clean
basis accounted for about 0.09 billion kilograms  (0.2  billion  pounds),
cotton  for 4.0 billion kilograms  (4 billion pounds) and man-made fibers
for 3.2 billion kilograms (7 billion pounds).

Among the man-made fibers, the most important are rayon, acetate, nylon,
acrylic, polyester, polypropylene, and glass fiber.

The natural fibers are supplied in  staple  form,   (staple  being  short
fibers) .    The  man-made  fibers  are  supplied  as  either  staple  or
continuous filament.  In either case the fiber is spun into yarn,  which
is  simply a number of filaments twisted together.  The yarn is woven or
knit into a fabric, and the fabric then dyed and treated to impart  such
characteristics  as  shrink  resistance,  crease  resistance,  etc.  The
finished fabric is delivered—directly or through  converters,  jobbers,
and wholesalers-to the manufacturer of textile products.

The  many  woven  fabrics  are  produced  by  variations  in the weaving
pattern.  Plain, or tafeta, weaves  give  such  fabrics  as  broadcloth,
calico,  cheesecloth,  muslin,  seersucker,  flannel  and  tweed.  Twill
weaves are represented by serge,  herringbone,  jersey,  gabardine,  and
ticking.  Because of their superior strength, twill fabrics are used for
work  clothes  and  men's  suits.  Satin weaves are smooth but weak; the
best known are crepe satin, sateen,  and  damask.   Dobby  and  Jacquard
weaves  are used to produce patterned fabrics.  Dobby weaves are used in
men's shirting and women's dress  fabrics.   Jacquard  weaves  are  used
extensively  for  upholstery  and drapery materials.  Finally, there are
the pile weaves, which include velvets, plushes, corduroys  and  turkish
toweling.

In  transforming  a  fiber into one of these woven fabrics, two types of
processes are used: wet and dry.  The SIC code breakdown is not particu-
larly useful for evaluating the waste effluent problems of  the  textile
industry.   These codes are grouped primarily by the process used--e.g.,
weaving or knitting--whereas the waste effluent problems stem  from  all
the  wet  processes  which  are used to desize,  wash, dye and finish the
textile fabric.  The wet processes of interest  include:  scouring,  de-
sizing,  mercerizing,  bleaching, bonding and laminating.  Dry processes
include:  spinning,  weaving  and  knitting.   Although  SIC  Code   226
identifies  textile  finishing,  Code 221 identifies weaving mills which
may also be integrated mills that have a finishing operation or  may  be
greige  goods  mills that have only dry processing.  Knitting mills fall
into a similar category; many of the mills identified as knitting mills,
in fact, process dyed yarns and, therefore, essentially  carry  out  dry
operations.
                                  13

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There  is no exact figure for the number of wet processing plants or the
total water use by the industry, but the Census  of  Manufacturers  gave
for  1968  under  Textile  Mill Products a total of 684 wet plants which
consume 412 billion liters (109 billion gallons) of  process  water  per
yaar.   (This  includes sanitary and cooling water, etc.)   A more recent
estimate, by the American  Textile  Manufacturers'  Institute  in  1970,
found  346  plants  using  394  billion liters  (104 billion gallons)  per
year, estimated to be 83 percent of the total industry use.

Table 4 gives details of the process water used and  discharged  divided
as  far  as possible according to the EPA categories.  The largest water
users are undoubtedly the finishing plants, with a total of 269  billion
liters  (71  billion  gallons) per year, averaging 2800 cubic meters per
day  (0.73 million gallons per day) .  The next highest  category  is  the
wool  finishing  operations,   with  47.3  billion  liters   (12.5 billion
gallons)  per year averaging 27000 cubic  meters  per  day   (0.7  million
gallons per day) but consisting of a much smaller segment of the textile
industry.

A  summary  of  this  data is presented in Table 5, which shows that 110
billion liters  (29 billion gallons) per year  or  26.6  percent  of  the
water was discharged to municipal sewers and 73.2 percent or 303 billion
liters (80 billion gallons) per year to surface water.  The 73.2 percent
also  divides  into  24.2 percent that received no treatment, 21 percent
that received primary treatment and 28.2 percent that received secondary
treatment before discharge.  Since 1968 many more treatment plants  have
been  built  and from a consideration of RAPP data and the recent survey
by the ATMI, we estimate that about 35 percent of the water used is  now
discharged  to  municipal  sewers,  15  percent receives no treatment, 5
percent receives primary treatment and  45  percent  receives  secondary
treatment.   Undoubtedly,  the  smaller  mills  or those using the least
amounts of  water  have  found  it  more  economical  to  use  municipal
treatment instead of constructing their own facilities.
                                   14

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Sources: Department of Commerce 1967 Census of Manufacturers
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                   Profile of Manufacturing Processes

As  mentioned  above the industry's basic raw materials are wool, cotton
and synthetic fibers.  The fiber and  fabric  finishing  operations  are
described  below  for  each  of  these  three materials.  Finally, these
operations are related to the selected subcategorization  through  brief
process   descriptions   of   each   subcategory.    The  rationale  for
subcategorization along with detailed descriptions of the seven segments
is given in Section IV.

Wool Fiber and Fabric Finishing Operations

Wool fiber consumption is smaller than either cotton or synthetic  fiber
consumption  and  the trend seems to be toward less demand in the future
on a percentage basis.  The operations required to produce  a  piece  of
finished  woolen  fabric are described below; either knitting or weaving
can be done at a given mill.  Scouring is the  first  wet  process  that
wool  fibers receive.  This process removes all the natural and acquired
impurities from the wcolen  fibers.   There  are  two  methods  of  wool
scouring  -  detergent  scouring  and  solvent  scouring.  In the United
States, the detergent  scouring  process  is  used  almost  exclusively.
There  are two types of detergent scouring - the soap-^alkali process and
the neutral detergent scouring process.  In the soap-alkali  process,  a
soap  or  synthetic detergent and a milk alkali such as sodium carbonate
or soda ash is added to a bath at a pH of 9.5  to  10.5  and  heated  to
temperatures  of  130°F.   This  process  consumes  a volume of 8,000 to
12,000 gallons of water per 1000 pounds of wool fiber.  In  the  neutral
detergent process, non-ionic detergents fo the ethylene oxide condensate
class are added to water at a pH of 6.5 to 7.5 and a temperature of 135°
to 160°F.

The  process  is  carried  out  in  a  series  of four open bowls called
"scouring train."  The first two bowls contain  the  detergent  or  soap
alkali  and  perform  the  scour.  The last two bowls serve to rinse the
fibers clean.  For every pound of scoured woolen fiber one and  one-half
pounds  of  waste  impurities  are  produced;  therefore,  wool scouring
produces one of the strongest industrial wastes in terms of  BOD.   This
process  contributes  55  to  75  percent  of the total BOD load in wool
finishing.

The next processes are the burrpicking and  carbonizing  step  which  is
done  to  remove  any  vegetable  matter  remaining  in  the  wool after
scouring.  If the wool is to be stock dyed, it is done prior to  dyeing;
if  the  wool  is  to  be  piece dyed, the fabric is carbonized prior to
dyeing.

Due to the popularity of multi-colored fabrics,  stock  dyeing  is  used
more  often  today  than  is piece good dyeing.  The two classes of dyes
used on wool fiber are acid dyes and metallized dyes.  In the dyeing  of
                                  17

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wool  fibers  it is impossible- to fix definite formulas.   The dye, grade
of wool, and the type of dyeing machine will alter the formulation.   in
the  acid  dyeing  baths  the temperature of the solution will vary from
140° to 212°F.  In the metallized dyeing the average  final  temperature
is 185°F.  The pH varies depending on the amount of residual alkali left
in  the  wool  fibers  after  the scouring process.  The  volume of waste
water generated by dyeing, either stock or  piece  goods   is  large  and
highly  colored.   The  BOD load is contributed by the process chemicals
used, and the contribution of wool dyeing to the mill's total  BOD  load
is 1 to 5 percent.

Although  the mixing and oiling step does not contribute  directly to the
water waste volume, the oil finds its way into the waste  stream  through
the  washing  after  fulling  operation.  The percentage  contribution of
total BOD load of this process varies with the type of  oil  used.   The
traditional  oiling  agent  is olive oil, which produces  a high BOD that
could contribute 10 percent of the total BOD load; however, there  is  a
trend  toward  the  use of non-ionic emulsifiers in oiling, that greatly
reduces the BOD contribution in this area.

Fulling is another operation that does not directly  contribute  to  the
waste  stream,  until the process chemicals are washed out of the fabric
in the wash after fulling operation.  There are two  common  methods  of
fulling,  alkali  fulling and acid fulling.  In the former case, soap or
synthetic detergent, soda ash, and sequestering agents are used  in  the
fulling  solution.   In  acid fulling, the fabric is impregnated with an
aqueous solution of sulfuric acid, hydrogen peroxide, and minor  amounts
of  metallic  catalysts   (chromium, copper and cobalt).  In either case,
the water is heated to a temperature of 90° to 100°F.  Acid  fulling  is
always followed by alkali fulling.

Following  the  fulling  operation,  the  goods are washed to remove the
fulling chemicals mentioned above and the carding oil described  in  the
mixing and oiling disussion.  It is estimated that from 10 to 25 percent
of  the fulled cloth's weight is composed of process chemicals that will
be washed out in this process and wasted.  Due to this large  amount  of
waste,  wool  washing after fulling is the second largest source of BOD,
contributing from 20 to 35 percent of the total.  The usual procedure in
this process is to subject the fulled cloth to two  soapings,  two  warm
rinses,  and  one cold rinse.  In the first soaping, nothing is added to
the water, the soaping action takes place when agitation of  the  fabric
causes the soap or synthetic detergent ot produce subs, thus washing the
fabric.   In  the  second  soaping,  a  2  percent  solution  of soap or
synthetic detergent is used.  The warm water rinsings are done  at  100°
to   110°F.,  while  the  cold  rinse  is done below 100°F.  This process
consumes from 40,000 to 100,000 gallons of water for each 1000 pounds of
wool fabric.  Analyses show  that  wool,  once  throughly  washed,  will
produce little or no BOD of itself on being rewashed.
                                  18

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After the dusting process, which follows carbonizing the fabric or stock
of  fibers,  the acids used in carbonizing must be removed.   In order to
accomplish this, the wool is rinsed to remove  the  bulk  of  the  acid.
Following  the  rinse,  the  wool  is neutralized by a low concentration
solution of sodium carbonate.  After this neutralization bath the fabric
is rinsed again.  Since sulfuric acid and soda ash  have  little  or  no
BOD, this process contributes less than 1 percent of the total BOD.

In  the  processing  of  woolen fibers, five sources of pollutional load
exist -  scouring,  dyeing,  washing  after  fulling,  neutralizing  the
carbonizing,  and  bleaching  with optical brighteners.  Figures 1 and 2
outline the operations that take place in woolen fabric manufacturing.

Cotton Fiber and Fabric Finishing Operations

The consumption of cotton fibers by textile mills in the  United  States
exceeds  that  of  any  other single fiber; however, the total synthetic
fiber poundage consumed by the textile industry is greater than that  of
cotton.   The  operations required to produce a piece of finished cotton
fabric are described below; either weaving or knitting can be done at  a
given mill.

Slashing is the first process in which liquid treatment is involved.  In
this  process,  the warp yarns are coated with "sizing" in order to give
them tensile strength to withstand the pressures exerted on them  during
the  weaving  operation.  Such substances as starch, starch substitutes,
polyvinyl alcohol, carboxy methyl cellulose, gelating glue and gums have
been used as size agents.  The  source  of  pollution  in  this  process
results  from the cleaning of slasher boxes, rolls, and make up kettles.
The volume is therefore usually low; nowever, the BOD can be quite high,
especially if starch is used.

The operation of desizing removes the substance applied to the yarns  in
the  slashing  operation,  by  hydrolyzing the size into a soluble form.
There are two methods of desizing - acid desizing and  enzyme  desizing.
In  acid desizing, the fabric is soaked in a solution of sulphuric acid,
at room temperature, for U to 12 hours, and then washed out.  In  enzyme
desizing,  couplex  organic  compounds produced from natural products or
malk extracts are used to solubilize the size.  The bath  is  maintained
at a temperature of 130° - 180°F. and a pH of 6-7.7, for a period of 4-8
hours.  Due to the unstable nature of these organic compounds, the whole
bath  must  be  discarded  after  each  batch.   After the size has been
solubilized, the fabric  is  rinsed  clean.   Desizing  contributes  the
largest BOD of all cotton finishing processes - about 45 percent.

scouring  follows  desizing.   In this process, the cotton was and other
non-cellulosic components of the cotton  are  removed  by  hot  alkaline
detergents  or  soap solutions.  In most modern plants, scouring is done
in conjunction with desizing rather than as separate operation.  Caustic
                                  19

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soda and  soda  ash  along  with  soaps  and  synthetic  detergents  and
inorganic reagents are used to remove the non-cellulois impurities.  The
bath  is  characterized  by  a pH of 10 to 13 and temperatures of 250°F.
Although the strength of alkali in the beginning  of  the  operation  is
between  1  percent  and  5  percent,  the  waste liquor will have a 0.3
percent alkaline concentration, the rest being taken out of solution  by
the  cotton  fibers.   As in the desizing operation,  the scouring process
is a batch operation requiring the fabric to remain  in the  kier  for  a
period  of  from  2  -  12  hours.   Scouring  is the second largest BOD
contributing process in the finishing of  cotton  textiles  -  about  31
percent.   Following  the  "boil-out," tne goods are rinsed with hot and
cold water to remove residual alkali.

Bleaching, the next process, removes the natural yellowish  coloring  of
the cotton fiber and renders it white.  The three bleaches most commonly
used  for  cotton are sodium hypochlorite, • hydrogen  peroxide, and sodium
chlorite.  In hypochlorite bleaching, the fabric  is  rinsed,  saturated
with a weak solution cf sulfuric or hydrochloric acid, rinsed again, and
then  passed  through  the  hypochlorite for a period of up to 24 hours.
Then process is done at room temperature with a pH range  of  9  to  11.
When  bleaching  with  sodium  chlorite, acetic acid is used in place of
sulfuric or hydrochloric acid, the temperature of the bath is hot   (180°
   185°F),  and  the  pH  is  3.5-5.5.   Hydrogen  peroxide  is used for
continuous bleaching.  This process calls for a washer, with  a  140°
175°F temperature, saturation with caustic soda at 175° - 180°F, passage
through  the peroxide at 195°F, and a final rinse.  The pH range used in
hydrogen peroxide bleaching is 9 to 10.  The final rinse may contain  an
antichlor,  sodium  bisulfite  or  sulfuric  acid,  to  remove  residual
chlorine from the fabric.  The bleaching process contributes the  lowest
BOD for cotton finishing.

The  mercerization  process  was  originally developed to give increased
luster to cotton fabrics.  Today it is still used for that purpose,  but
more  importantly  to impart increased dye affinity and tensile strength
to the fabric.  It is estimated that  only  30  percent  of  all  cotton
fabrics  are  now  mercerized,  and  with  the increasing use of cotton-
polyester blends, less will probably be done in the  future.  The process
uses a  15 to 30 percent solution of sodium hydroxide at room temperature
for 1/2 to 3 minutes.  The fabric is then rinsed  in  an  acid  wash  to
neutralize  the fabric and washed in water and then dried.  The effluent
from this process is alkaline and high in dissolved solids, but  low  in
BOD.

After  mercerizing,  the  goods are sent tc the dye house or color  shop.
In the dye house they are dyed either in small volumes of batch  process
machines,  or  on  continuous dyeing ranges in large volumes.  There are
five important classes of dyes used on cotton fabrics:  vat,  developed,
sulphur, direct, and aniline black.
                                  20

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The  dyeing process is carried out in an aqueous bath with pH variations
In the color shop,  the  aoods  are  printed  with  colored  designs  or
patterns.   The  usual  method  is  by  roller  machines.   The color is
imparted to the fabric from the rolls which contain the printing  paste.
This  paste  contains  dye,  thickener,  hygroscopic  substances, dyeing
assistants, water, and other chemicals.  The pollutional load  from  the
color  shop  comes  mainly  from  the wash-down rinses used to clean the
equipment in the shop and the clorh rinsings.  The pollutional  load  is
rather  low  in both volume and BOD.  When a mill does both printing and
dyeing, the BOD contribution of the combined processes  is  17  percent,
and the total BOD load comes from -ne process chemicals used.

Synthetic Fiber and Fabric Finishing Operations

In  this category of textile fibers there are two broad classifications:
cellulosic and non-cellulosic fibers.  The two major  cellulosic  fibers
are  rayon  and  cellulose acetate.  The major non-cellulosic fibers are
nylon, polyester, acrylics and modacrylics.  There are other  fibers  in
both  classes, but at present they are not consumed in as large a volume
as the six fibers mentioned above.   The  largest  volume  of  synthetic
fibers  consumed  by textile mills comes from the non-cellulosic fibers;
and  the  trend  is  toward  an  even  greater  demand  in  the  future,
particularly  for  polyester  fibers.  Synthetic fibers can be converted
into fabrics in one of two ways.  Continuous filament yarns can be  used
to  manufacture  100  percent  synthetic fabrics, or staple yarns can ba
used to produce fabrics that are blends of man-made fibers  or  man-made
and  natural  fibers.   Blended  fabrics  are processed according to the
natural fiber component of the yarn.  As in cotton and wool  processing,
the yarns are either woven or knitted as a given mill.

The  first  process  in which synthetic fibers are subject to an aqueous
treatment is stock dyeing, unless the fabric is to be piece dyed.   When
stock  dyeing is used, the liquid waste discharge will vary from about 8
to 15 times the weight of the fibers dyed.

Due to the low moisture regain of the synthetics, static electricity  is
a problem during processing.  To minimize this problem, anti-static oils
are  applied  to  the  yarns,  which also serve as lubricants and sizing
compounds.   These  compounds  commonly  used  are:  polyvinyl  alcohol,
styrene-base  resins, polyalkylen glycols, gelatin, polyarylic acid, and
polyvinyl acetate.  These compounds become a source of  water  pollution
when  they  are  removed  from  the  fabrics during scouring.  Since the
manufacture  of  synthetic  fibers  can  be  well  controlled,  chemical
impurities  are relatively absent in these fibers; therefore, only light
scouring and little or no bleaching are required prior to dyeing; and if
synthetics are bleached, the process is not normally a source of organic
or suspended  solids  pollution;  however,  the  process  will  generate
dissolved solids if chlorine bleaches are used.
                                  21

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Process Description by Subcategory
          Y  1  - Wool Scouring^  A generalized flow diagram of the wool
scouring process is shown in Figure 1.   Scouring consists of sorting the
fleece and feeding it to a hopper.  The wool then is carried  through  a
series  cf scouring bowls where scour liquor flows countercurrent to it.
Detergent is added in the third or fourth bowls to emulsify the  greases
and  oils.   The scoured wool is then dried.  In mills where the cleaned
wool is converted into wool top, the wool is  combed  and  gilled.    The
products are short fibers (used for wool yarn)  and long fibers (used for
worsted yarn) .
          Y 2. ~ Wool Finishing:   The wool finishing process is depicted
in Figure 2.  The three distinct finishing processes are shown as stock,
yarn  and  fabric  finishing.   Because  the  pollution generated by the
fabric finishing operation is similar to that  generated  by  the  other
two,  fabric  finishing  is  included in this discussion.  If the greige
goods are 100 percent wool, they are first cleaned of  vegetable  matter
by  carbonizing  and then cleaned of spinning oils and any weaving sizes
by a light scour.   The  100  percent  woolens  are  then  dimensionally
stabilized,  principally  by "fulling," or mechanical working of the wet
fabric in the presence of detergents, to produce a controlled  shrinkage
or  "felting."  Worsteds  and most wool- synthetic blends are not fulled.
Worsteds are hard, tightly-woven and dimensionally stable as received at
the finishing plant; woclens  are  loosely-woven,  soft  and  often  are
firmed up by fulling.

The  fabric  is  then dyed in batches in vessels called becks, washed in
the same vessels, and taken to dry finishing operations.  The  only  dry
finishing operation of concern to water pollution is mothproofing.
                                  22

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             3  -  Greicje  Mills_:_    weaving textile yarns into a fabric
requires application of size to the warp yarns in order  to  resist  the
abrasive  effects  of  the  filling yarns as these are positioned by the
shuttle action of the loom.  Greige mills apply the  size  and  complete
the weaving.  Many operate as completely independent facilities.  Figure
3 shows operations generally performed at this type of greige mill.

weaving is a dry operation, but is normally done in buildings maintained
at  high  humidity.   Under these conditions, the size film is flexible,
and yarn breaks on the loom are minimized.  Yarns sized  with  polyvinyl
alcohol  may be woven at a somewhat lower humidity than yarns sized with
starch.  Cooling and humidifying water used in a greige mill  represents
a  substantial portion of the total water usage.  Industrial wastes from
knit greige good is nil.  If any wastes are generated they are from  the
knitting  oils, however, these would only enter the waste stream through
spills, wash up or possible washing of the final product.

For carpet backing, a continuous applicator applies a foamed latex layer
to the carpet's underside.  In double-backed carpet, a layer of unfoamed
latex is applied in the same manner,  and  a  final  fabric  backing  is
pressed  on,  being  cemented  in place by the latex.  In either case, a
liquid latex waste is generated.  Some of the latex becomes hardened, so
a mixture of solid and liquid latex results.  Some of this  material  is
collected  by  shovelling  it into a barrel for land-fill disposal.  The
rest is washed off by hosing and removed by coagulation.
Subcategory ^ ~ Woven Fabric Finishing  Wet processes which are used in
finishing woven greige fabric may be divided  into  two  groups:   those
used to remove impurities, clean or modify the cloth; and those in which
a chemical is added to the cloth.

The  first  of  these  groups  includes  desizing,  scouring, bleaching,
mercerizing, carbonizing and fulling.  Only cotton and cotton blends are
mercerized.  The last two of these processes are used only on  wool  and
wool blends.

The   second   group  of  processes  includes  dyeing,  printing,  resin
treatment, water proofing, flame proofing, soil  repellency  and  a  few
special  finishes  whose  use  represents a very small proportion of the
total.

Certain fabrics, including denims and  some  drapery  goods,  are  "loom
finished."  In production of these goods, the warp yarns are dyed, woven
to  a  fabric, and the fabric finished with a permanent size.  For these
fabrics, the  first  group  of  processes  listed  above  (cleaning  and
preparing  the  cloth)   is  avoided  entirely.   For  this reason, mills
producing this group of fabrics may be a subcategory, although  we  have
not  treated  it  as such.  The degree of finishing necessary to provide
fabric ready for  sale  depends  significantly  on  the  fiber (s)  being
                                  25

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processed.   The  natural  fibers  (cotton and wool)  contain substantial
impurities, even after they have been woven as greige goods, and require
special treatments to convert them to the  completely  white,  uniformly
absorbent  form  that  is  essential  for  dyeing, resin treatment, etc.
Synthetic fibers contain only those impurities that were  necessary  for
manufacture of the fiber and spinning to obtain yarn.

The  different  operations  listed  above  have  been  described  in the
literature.  A. flow sheet for woven fabric finishing is given in  Figure
4.

Subcategory_  5  _ Knit Fabric Finishing:   The wet processing operations
performed in knit fabric finishing are shown schematically in Figure  5.
This  is  necessarily  a  generalized flowsheet; the specific operations
employed in a given plant will vary from plant to  plant.   In  general,
the  yarns are purchased in the undyed state, with a knitting oil finish
to provide lubrication for the knitting operation.  The amount of finish
on the yarn ranges from 1 to 7 percent depending on the type of yarn and
fiber.  This is a significant difference from weaving  yarns  which  are
sized with starch or ether polymeric materials.  After the yarn has been
knitted  into  fabric, the fabric may be processed by one or more of the
alternative routes indicated in Figure 5.  The  wet  process  operations
employed  in  a plant depend on the nature of the goods involved and the
end product requirements.

Subcateqory (5 - Garget Millsi  Carpets are yarn dyed,  piece  dyed,  and
printed.   When  yarn  dyed  carpets are made, the yarn is often dyed in
another mill and brought to the carpet mill.  The relative quantities of
yarn, beck, and continuous dyeing, and printing and  latexing  may  vary
widely.

The  yarn  is tufted onto a polypropylene or jute woven backing in a dry
operation  (Figure 6).  Following this, the tufted carpet can  be  either
printed   or  dyed.   If  printed,  a  semi-continuous  screen  printing
operation is performed, followed by a wash and rinse step  in  the  same
machine.   If  dyed,  the most common method is beck dyeing, in a manner
quite similar to that described in previous categories for  yard  goods.
The industry claims a higher liquor-to-fabric ratio, however, because of
the  difficulty  in making the carpet sink and become thoroughly wetted.
Many small air bubbles become entrapped in the  tufts.   The  continuous
dyeing appears very similar to the continous pad-stream process used for
cotton/synthetic  blends  broad-woven  finishing.   After it is dyed the
carpet is dried in a  tunnel  drier.   The  carpet  is  then  ready  for
application of either a single or a double backing.

Subcategory. 7 - Stock and Yarn Dyeing and Finishing: In this category is
crude  yarn obtained from a spinning facility.  The yarn may be natural,
synthetic, or  blended.   Wet  processes  used  by  yarn  mills  include
scouring, bleaching, mercerizing and dyeing  (Figure 7).
                                  26

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Several  techniques  are  available  for  processing  raw  yarn into the
finished product.   The mcst common process is probably  package  dyeing,
but  other  processes,  such  as  space dyeing, are widely used.   In the
former process, yarn wound on perforated tubes  is  placed  in  a  large
vessel,   which   is  sealed.   The  dye  solution,  at  an  appropriate
temperature, is circulated through the yarn.   The dyed yarn  is  washed,
rinsed and dried.   In space dyeing, yarn is knit and the fabric is piece
dyed,  washed,  rinsed and dried.   The fabric is then unravelled and the
yarn is wound on cones.
                                  27

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                               SECTION IV

                        INDUSTRY CATEGORIZATION

                          PREVIOUS APPROACHES


In   deriving   this   industry    categorization    system,    existing
categorizations  and other previous attempts at categorization have been
considered.  The principal systems investigated were:

    A.   SIC codes.  These codes do not lend themselves to a
         classification of the industry with respect to
         characterization of the pollution loads generated.  For
         example, Subcategory 3, Greige Goods, includes 10 SIC categories.

    b.   The method advanced by the report, «'A Simplification of Textile
         Waste Survey and Treatment" by Masselli, Masselli and Burford.
         This approach consists of synthesizing the raw waste load from
         a textile mill by additive contributions of the chemicals used.
         Tables of BOC values for many chemicals are given in the report.
         This method was judged too difficult to be implemented by persons
         not versed in Textile chemistry and not knowledgeable about the
         chemicals used.

    c.   A previous categorization scheme prepared for EPA which
         employed unit processes to synthesize the raw waste loads.
         This method was also judged too difficult to implement.

    d.   The preliminary system developed by EPA in the "interim
         guidance" for the textile industry.

    e.   The system developed by the Institute of Textile Technology
         and Hydrosciences in the study for the American Textile
         Manufacturer's Institute, Inc., and Carpet and Rug Institute.

Based on knowledge of the various pollution problems, loads generated by
the different unit  operations  in  the  textile  industry,  actual  and
potential  waste  treatment  practices  and  current  manufacturing  and
processing  practices,  these  five   approaches   were   combined   and
simplified.

The  last  two  methods   (d  and e) and the present one have in common a
categorization according to the products produced by a mill that in turn
relates to type of wastes.

A  comparison  of  the   EPA   interim   guidance   and   the   ATMI/CRI
categorizations with those used in this study is given in Table 6.
                                  33

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Categorization

The  following  factors were considered in establishing subcategories in
the textile industry.
    a)   raw material
    b)   age and size of facilities
    c)   products and production processes
    d)   location and climate
    e)   waste treatability

The principal basis for subcategorization is the  configuration  of  the
predominant  material  being  processed.   Knit  and  woven  fabrics are
different and each is different  from  carpet,  yarn  or  other  fibers.
Special  processes  such  as wool scouring and latex application provide
additional subcategorization.  Waste water  volume  and  characteristics
vary  widely  for  the different materials and processes and support the
proposed   categorization.    Although   waste    water    volume    and
characteristics  vary  significantly, the treatability of textile wastes
by similar biological treatment methods has  been  demonstrated.   Thus,
subcategorization  by  waste treatability is not required.  Location and
climate have a material effect upon pollution  control  methodology  for
any  given operation or segment of the industry.  However, the impact of
either  location  or  climate  is  not  sufficient   for   defining   or
substantiating  subcategories.    (Variability in treatment operation has
been taken into account in section IX).  Available data  indicates  that
neither  the  age nor the size of facilities significantly affects waste
character or water usage.  Any technological effect of size  or  age  is
predominately  reflected in the type or size of production facility, and
was taken into consideration through this factor.

The subcategorization selected for the purpose of developing waste water
effluent limitations guidelines and standards are as follows:

     1.  Wool scouring
     2.  Wool finishing
     3.  Greige mills
     4.  Woven fabric finishing
     5.  Knit fabric finishing
     6.  Carpet mills
     7.  Stock and yarn dyeing and finishing

Subcategories 1 and 2 deal with wool processing; subcategories 3,
U, 5 and 7 covers the various types of processing for cotton and
synthetic fibers; and subcategory 6 covers the carpet industry.
These subcategories are described in detail below.
                                  35

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Subcategor_Y 1 - Wool Scouring

Wool scouring and topmaking is conveniently separated as  a  subcategory
and  a  significant  number  of plants perform this function alone.  The
initial washing and cleaning of wool generates a wide variety of organic
and inorganic products in the waste effluent.    The  raw  wool  contains
suint,  dirt,  and grease along with oils such as lanolin.,  In addition,
the preparation and cleaning of wool requires  a heavy use of detergents.
Recovery of wool grease has some  economic  incentive  in  that  it  has
market  value.  However, even with grease recovery, wool scouring wastes
present a highly concentrated waste.

Wool scouring is conveniently  separated  from  other  segments  of  the
textile industry because of its uniqueness.  Raw wool (grease wool) must
be  wet  processed  to clean it before the1 fiber may be dry processed to
produce fiber, yarn or fabric for the further  wet processing steps found
in a finishing plant.  Neither cottcn nor the  synthetic  fibers  require
this  initial  wet-cleaning.   Furthermore, most wool scouring mills are
geographically separate from other textile operations.  Exceptions exist
where wool scouring is physically separated from, but shares  the  waste
treatment plant with, finishing mills.

The grease wool contains 25 to 75 percent non-wool materials, consisting
of  wool grease and other excretions and secretions of the sheep such as
urine, feces, sweat and blood, as well as dirt consisting of  both  soil
and  vegetable  matter.   Additional  materials  that may be present are
insecticides  (sheep dip) , and fugitive  dyes  used  for  identification.
This  variability  in  yield  and  in  the composition of impurities and
grease causes a correspondingly variability in raw waste loads.

        orY  2 - Wool Finishing
Wool finishing involves the use of specialized  dyes  peculiar  to  this
fiber  which  often  result  in  the  presence  of chromium in the waste
effluent.  In addition, phenols  occur  from  dyeing  polyester  blends.
Only  a  small  amount  of  pure wool is now processed.  The bulk of the
operations involves wool-polyester blends which give high BOD loads from
the dye carrier which is used.  The  resulting  wastes  are  similar  to
those  in  Woven  Fabric Finishing and Knit Fabric Finishing, but have a
higher raw waste load.

Several major mills have integrated wool scouring and  top  making  with
wool  finishing.   Such  mills  can  be accommodated by a combination of
Subcategories 1 and 2.

This industry consists of many small mills — most of them in the  North
 (New  England,  New  York  and New Jersey) and most are fully integrated
                                  36

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mills -- and about 25 larger mills, mostly in the South  (Virginia,  the
Carolinas and Georgia) .

A  sample  of  29 textile mills participated in a waste treatment survey
prepared by the Wool  Manufacturers  Council  of  the  Northern  Textile
Association.   Of the 29 mills, 25 were wool finishers and 4 were cotton
and synthetic mills.  Of the 29 mills  7  have  completed  tie-ins  into
municipal treatment facilities: 15 plan to tie into municipal facilities
that are in various stages of construction or planning; 4 have completed
private  treatment  facilities  and  3  have  plans to construct private
treatment facilities.

Most small mills do some commission dyeing, and even  the  larger  mills
that  are  part  of  the larger corporations commonly perform commission
dyeing.  Commission dyeing operations imply a wide range of fabrics  and
finishes as well as fiber types.

Probably not more than five mills still do more than 50 percent wool and
wool blends:  the rest process primarily other fabrics.

The  processes  of  carding  and spinning wool into yarn, and subsequent
weaving or knitting into fabric are included in  Subcategory  3,  Greige
Mills.

Yarns  made from wool are classified into either woolen yarns or worsted
yarns.  Woolen yarns are characteristically of  loose  construction  and
composed  of  relatively  short  fibers;  worsted  yarns  are  of  tight
construction with few protruding fiber ends  and  composed  of  selected
long fibers (tops).  As a result, worsted yarns are stronger.

Wool  finishing  has been differentiated from other finishing categories
because of  (1) the wide  variety  of  chemicals  used  to  process  wool
fabrics and (2) high raw waste loading.

In addition to processing all wool fabrics, today's wool finishing mills
process  wool  blend  fabrics and fabrics made of 100% synthetic fibers.
The percentage of wool used by a woolen mill is based on  market  demand
and  availability  of  wool.  The variety of fabrics varies from mill to
mill, season to season and year to year.  Shifts back and forth  between
fibers cannot be predicted.

Few  of  today's  wool  finishing  mills  process all wool.  Many of the
woolen mills by name handle 20 percent or less  wool  with  the  balance
being  woven  and  knit synthetics.  Also, within the 20 percent or less
portion, woolen/synthetic blends (most  often  with  polyester)   usually
constitute the bulk of the fabric.
                                                            j
High  water  usage  in the subcategory appears to be a result of washing
after the fulling operation (peculiar  to  100  percent  wool  fabrics).
                                  37

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Size  as  used on cotton and synthetic wovens is not used by wool mills.
Wax lubricants and emulsified oil are sometimes used in processing  wool
yarns.   These  waxes  and  oils  are  difficult  to  remove and require
thorough washing to be removed properly.  Because of the low  percentage
of  wool  actually  processed  in  mills  today, and the small amount of
sizing used, this category appears in most ways similar  to  Subcategory
5, Knit Finishing.

Variations  occur  in processing, similar to other finishing categories,
in that some fabrics are woven or knit from yarns that are already dyed,
either in the fiber or yarn form.  A given mill may dye and finish  part
of its production while only finishing the remainder.

SubcategorY 3 - Greige Mills and Garget Backing

Although  there  are  many greige goods mills, they carry out mainly dry
operations  (with the exception of slashing)  and hence contribute  little
to  the  overall waste problems of the textile industry.  In many plants
the sanitary BOD load is comparable  to  the  process  BOD  load.   This
category  applies  equally  well  to  woven or knitted greige goods, and
because of the similar dry nature of  carpet  backing  operations  these
mills are included in this subcategory.

Greige  goods  manufacturing  includes spinning and texturizing of yarns
which require a lubricating oil, similar to mineral oil.   This  oil  is
applied  to the fibers or yarns and stays with them, to be removed prior
to dyeing in the dye house.  However, some oil finds its  way  into  the
drains because of clean-ups and spills.

Prior  to  being  woven,  the yarns are coated with a sizing material to
give the yarn both lubrication and  strength  that  will  permit  it  to
withstand  the  severe mechanical demands of weaving.  Cottons generally
are coated with starch and synthetics with polyvinyl alcohol.  Wool  and
wool  blends  are  seldom sized, unless the yarns are quite fine.  Since
most wool yarns are blends, both  starch  and  PVA  may  be  used.   The
slasher,  where  the sizing is applied, is washed down about once a week
and thus contributes to the liquid wastes.   Generally  the  waste  flow
from  the  slashing  operation  represents a low percentage of the total
plant flow.

Greige mills generally  manufacture  yarn  and  unfinished  fabric.   In
general  greige  mills include the production of woven greige goods knit
greige goods and greige yarn production.   However,  knit  greige  goods
production  is  almost  always  combined  with a finishing operation and
therefore may be included in the knit  finishing  subcate;gory.   Carpets
are sometimes backed in a separate plant.  The industrial portion of the
waste  water consists of equipment washing which may be performed once a
day or once a week.  The resulting waste flow is small.
                                  38

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It has been estimated that there are 600 to 700 greige woven  mills,   80
percent of which are in North Carolina, South Carolina, Georgia, Alabama
and  Virginia.    Perhaps  20  percent  of  the  600 have their own waste
treatment plants, with almost  all  the  rest  disposing  of  wastes   at
municipal  facilities.   Less  than  5 percent is believed to dispose of
their wastes in waterways without treatment.  No  carpet  backing  mills
were found which did not discharge to a municipal system.

Subcategory ± - Woven Fabric Finishing

This  category  is  one  of  the  most  important,   because  such plants
constitute much  of  the  waste  water  effluent  load  in  the  textile
industry.   Integrated woven fabric finishing mills are included in this
subcategory because the greige goods section of these mills  contributes
only a small amount to the overall effluent load.

The  size  removed after weaving is a major contribution to the BOD load
from the plant.  Two sizing compounds are commonly employed:  starch and
polyvinyl alcohol  (PVA) .  PVA tends to  be  less  readily  biodegradable
than  starch and therefore presents a lower BOD5 level but contributes a
high COD level.  In addition to high BOD, the wastes generally have high
total dissolved solids, color, and a variety of dispersing agents.  They
also may be very alkaline from the use of caustic  soda  in  mercerizing
cottons.
     dyes  and  associated  additives  used  in  woven  fabric finishing
represent the most complicated problem, since the BOD load and color can
vary considerably with the type of dye fabric being  processed  and  the
color effects to be achieved.

Processing  steps in this category generally include cleaning the greige
goods, bleaching, mercerizing of cotton (treating with caustic) , dyeing,
washing and rinsing, followed by application of finishes  such  as  soil
repellents, anti-statics, etc.

This  category encompasses mills which finish woven goods (or integrated
greige goods and finishing mills) .  It has been estimated that about 600
mills fall into subcategory 4.  About 20 percent treat their own  waste,
75  percent  enters  municipal  systems,  and  5  percent  have no waste
treatment.

This category predominates in the Southeast  (North and  South  Carolina,
Georgia,  Virginia, Alabama) , but there are some large operations in New
York and New England.
                                  39

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            5 - Knit Fabric Finishing

The main difference between woven and knit fabric finishing is that  the
sizing/desizing  and  mercerizing operations are not required for knits;
therefore, raw waste load levels are lower.

The knitting industry is characterized by a large number of plants and a
structure organized  along  specialized  product  segments.   The  major
segments are knit fabric piece goods, hosiery,  outerwear, and underwear.

While  the  industry has shown substantial growth in value of shipments,
it has been estimated that through consolidation and other  factors  the
current  number  of  plants  in  this  industry  is about 2500.  Of this
number, it has been estimated that  about  1100  plants  have  only  dry
operations.   These  are  plants  such as sweater mills in the outerwear
segment, which knit goods from purchased or commission  dyed  yarns,  or
mills  which  have  finished  goods  dyed  on  a  commission  basis  and
therefore, have no process water  requirements.   Most  of  the  sweater
mills  are  located in the Northeast.  In those isolated instances where
sweater or similar mills dye their  own  yarn,   these  mills  should  be
subject to subcategory 7 guidelines.

Of  the 1400 plants believed to have wet process operations, it has been
estimated that 85 percent discharge to municipal treatment systems.  The
great bulk of these are hosiery plants  (700-800)  located  primarily  in
North Carolina, Tennessee, and Pennsylvania.

The  knit  fabric  segment  of the industry has about 540 plants.  These
plants are the source of finished knit  piece  or  yard  goods  for  the
apparel,  industrial,  and  household  goods  trades,  and also serve to
augment supplies of fabric to  underwear  and  outerwear  manufacturers.
These  plants  are  the  main  subject of subcateogry 5.  The large knit
fabric plants are  located  mainly  in  North  and  South  Carolina  and
Georgia,  but  substantial  numbers  are  also  located in New York, and
Pennsylvania.

            £ ~ Carpet Mills
Carpet mills form  a  distinct  part  of  the  industry  although  their
effluents  are  similar  in  many  ways  to those of Subcategory 5, Knit
Fabric Finishing.  Carpets use mostly synthetic fibers  (nylon,  acrylics
and  polyesters) but some wool is still processed.  As in Subcategory 2,
Wool Finishing, such wool carpet mills produce synthetics as well.  As a
result, no subcategory for wool carpets is proposed.

Carpet sometimes is backed with latex in  a  separate  plant.   However,
carpet  mills   often  do  latexing in the same plant with the finishing.
Latex is settled in separate basins prior to release of  the  segregated
                                  40

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stream  to the treatment plant and the additional load on these mills is
negligible.

Tufted carpets account for well over 65 percent of  the  plants  and  86
percent  of  the  dollar  volume,  and  constitute  74  percent  of  the
employment in this industry.  Therefore, the  guidelines  are  generated
principally  around  this  segment.  About 70 percent of the industry is
located in Dalton, Georgia  and  these  mills  are  connected  into  the
municipal  treating  system.  However, the remaining carpet mills are of
sufficient quantity to warrant effluent guidelines.

Tufted carpets consist of face yarn that is looped through a  woven  mat
backing   (mostly  polypropylene,  some  jute), dyed or printed, and then
backed with either latex foam or coated with  latex  and  a  burlap-type
woven fabric backing put over the latex.

The dominant face yarn is nylon, followed by acrylic and modacrylic, and
polyester;  the  latter  two  groups  in total are about equal to nylon.
Since dyeing of these fibers  in  carpets  differs  little  from  dyeing
fabric,  the  dyeing  descriptions  for  these  fibers  given  in  other
categories applies here.  Beck, continuous dyeing, and  screen  printing
are practiced.

The  latex  operational  load  on  the  waste  treatment  facility of an
integrated  mill,  after  adequate  pretreatment  by   coagulation,   is
insignificant.

Subcateqory 7 - Stock and Yarn Dyeing and Finishing

Yarn  dyeing  and  finishing  are  different from woven fabric finishing
because there is no sizing and desizing operation.  They  are  different
from  knit  fabric finishing because of their mercerizing operations and
water use.   The  combined  differences  are  sufficient  to  justify  a
separate  category.   The  waste  loads from this type of plant can vary
more than  those  from  other  types  of  integrated  textile  mills  or
finishing  mills.  Many multiple-operation, commission houses fall under
this category.

Subcategory 7 includes plants which clean, dye and finish fiber stock or
yarn.  The plants may or may not have yarn spinning facilities.   sewing
thread, textile and carpet yarn are typical products.

It  has  been  estimated  that 750 plants fall into this category.  Most
(probably 80 percent)  dispose of their wastes at  municipal  facilities.
We  believe that 5 to 10 percent treat their own waste and the rest have
no waste treatment facilities.
                                  U1

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About 60 percent of yarn dyeing and finishing is performed in  Virginia,
North  Carolina, South Carolina, Georgia and Alabama, with the remainder
distributed across the eastern U.S. and the Far West.

Categorization: Economic Considerations


The size of the production  facilities  is  another  significant  factor
which  requires  an  exception  within  the  subcategorization.   Severe
diseconomies of scale create economic  impacts  which  require  separate
limitations  for small plants.  As illustrated in Section VIII, the unit
costs  attributable  to  activated  carbon  adsorption  (best  available
technology) for small industry plants as compared to medium sized plants
are  reflected  in  an  average  price increase for a small plant of 4.2
cents per kilogram product  (1.9 cents per pound of product) as  compared
with an average price increase for a medium sized plant of 2.3 cents per
kilogram   (1.0  cents per pound) .  It is estimated that disproportionate
cost increases such as those indicated above would force the closing  of
as many as 500 small facilities.  Thus, an exemption in the form of less
stringent  limitations  is  required for small textile mills.  The basis
for this size exception is based on economic trends developed in Section
VIII and developed in Table 7.

The subcategories including size exemptions selected for the purpose  of
developing waste water effluent limitations guidelines and standards are
as follows:

    1.  WOOL SCOURING
        Plant capacity less than 6,500 kg/day (14,300 Ib/day)
        Plant capacity greater than 6,500 kg/day  (14,300 Ib/day)

    2.  WOOL FINISHING
        Plant capacity less than 900 kg/day  (1,980 Ib/day)
        Plant capacity greater than 900 kg/day  (1,980 Ib/day)

    3.  GREIGE MILLS

    4.  WOVEN FABRIC FINISHING
        Plant capacity less than 1000 kg/day  (2,200 Ib/day)
        Plant capacity greater than 1000 kg/day  (2,200 Ib/day)

    5.  KNIT FABRIC FINISHING
        Plant capacity less than 3,450 kg/day (7,590 Ib/day)
        Plant capacity greater than 3,450 kg/day  (7,590 Ib/day)

    6.  CARPET MILLS
        Plant capacity less than 3,450 kg/day (7,590 Ib/day)
        Plant capacity greater than 3,450 kg/day  (7,590 Ib/day)
                                  42

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STOCK AND YARN DYEING AND FINISHING
Plant capacity less than 3,100 kg/day  (6,820  Ib/day)
Plant capacity greater than 3,100 kg/day  (6,820 Ib/day)

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                                   TABLE
         BASIS FOR SIZE EXCEPTION WITHIN TEXTILE SUBCATEGORIZATION
Number
of
Employees
1-4
5-9
10-19
20-49
50-99
100-249
250-499
499-2,499
Total
1-19
Percent
Ib product/day
Employee
No. Employees
(Ib/day)
(1000)
kg/day
(1000)
Number of Establishments By
1
14
5
10
21
6
7
4
1
68
29
(43%)
750
19
14.3
6.5
2
54
17
22
64
41
60
35
17
310
93
(30%)
100
19
1.98
0.9
3(1) £
63
27
56
91
76
70
32
51
449
146
(33%)
120
19
2.2
1.0
5 6_(2)
95
59
93
124
63
75
23
9
541
247
(46%)
400 400
19 19
7.59 7.
3.45 3.
Subcategory
1_
38
23
25
40
32
20
10
3
192
86
(45%)
360
19
59 6.82
45 3.10
(1)   No size exception for Subcategory 3 because of small waste load.

(2)   Size exception calculated from associated data because only
     limited economic data available on carpet mills.

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                               SECTION V

                         WASTE CHARACTERISTICS

                              INTRODUCTION

Many  of  the  mechanical  operations used in the manufacture of textile
fabrics are common to the industry as a whole and the character  of  the
waste  waters  are  similar.  Typically, the textile fibers are combined
into yarns and then the yarns  into  fabrics.   After  the  fabrics  are
manufactured,  they  are  subjec-c  to several wet processes collectively
known as finishing and it is in  these  finishing  operations  that  the
major waste effluents are produced.

In  Section  III  wool,  cotton and synthetic fiber and fabric finishing
operations  were  briefly  described.   General  descriptions   of   the
manufacturing  processes  were  given  in  Section IV for the purpose of
industry subcategorization.  In this section the waste warers from  each
operation within each subcategory are characterized.

The  principle  parameters used to characterize waste effluents were the
flow, biochemical oxygen demand, chemical oxygen demand,  total suspended
solids and oil and grease.  As discussed in section VI, these parameters
are considered to be the best available measure of the waste load.

Subcategory 1 - Raw Wool Scouring


The raw waste from raw wool scouring is different from  the  waste  from
all  other  categories  used  in  this  study:  it  contains significant
quantities of oil and grease, even after in-process recovery.  The  wool
grease  constitutes  a  special  problem  in treatment since it does not
appear to be readily biodegradable.  Therefore, a grease  recovery  step
is important to reduce pollution.


Sulfur  is  brought  in  with  the  wool,  as well as phenolic and other
organic materials derived from the  sheep  urine,  feces,  blood,  tars,
branding fluids and sheep-dips used in insecticides.  These irems appear
randomly in the effluent.

Wool  scouring is generally performed in a series of scouring bowls.  In
these scouring bowls, the heavier dirt and grit  settles  to  the  cone-

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shaped bottoms where it is blown down once an hour or so, and carried to
the treatment plant by scour liquor.

The  scour  liquor, after picking up the soluble and less heavy dirt and
grit, is piped to a separation tank where further settling of  dirt  and
grit  occurs.   This  material  is  also  blown  down and carried to the
treatment plant once a day, or more often if the  dirt  content  of  the
wool is high.

From  the  separation tank the scouring liquor is processed to break the
emulsion and recovery of the wool grease.  Two methods are commonly used
to do this: centrifuging and acid-cracking.

In cantrifuging (as shown  in  Figure  1)  the  top  low-density  stream
contains  concentrated  grease, which is further dewatered in additional
centrifuges to yield the recovered, unrefined wool grease.  The  medium-
density  stream  is  combined with the relatively clean bottoms from the
auxiliary centrifuges and recycled to the wool scouring train  as  fresh
scour  liquor.  The high-density-bottoms streams consists mainly of dirt
and grit, and is sent to the treatment plant.

An alternative means to  break  the  grease  emulsion  for  wool  grease
recovery  is  the  acid-cracking  grease  recovery system, also shown in
Figure 1.  sulfuric acid is added to  the  scour  liquor  to  break  the
grease/water  emulsion.  Heating the mixture increases the efficiency of
separation.  The grease is separated from the liquor in a settling  tank
and  recovered.   The liquor is then treated with lime to neutralize the
acid and subsequently passes through the waste treatment plant.

In the centrifugal method, about 60 percent of the grease is  recovered:
the remaining 40 percent is attached to the dirt and grit.  In the acid-
cracking method, pilot plant performance indicates a 98 percent recovery
of grease from the degritted liquor.

Grease  yield,  in  total  ,  is 8 to 15 percent by weight of the greasy
wool, and this constitues 50 to 65 percent of the wool grease  initially
present.    (Ref. 141).  Note that 1-3 percent of the wool grease present
in the grease wool is allowed to remain in the wool as a conditioner.

Also, alkaline scouring has been used in which soda ash is added to  the
wash  water.  The soda ash combines with seme of the wool grease to form
a natural soap, thereby  requiring  less  detergent  but  also  lowering
recovered wool grease yield.

Objections  to  increased recycling of the scour liquor have been voiced
by industry, but  with appropriate  technological  innovation,  an  even
greater amount of recycling may be possible.

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Objections  to  increased recycling of the scour liquor have been voiced
by industry, but with  appropriate  technological  innovation,   an  even
greater amount of recycling may be possible.

Some  "raw" wools, mostly the Australian and New Zealand wools, are pre-
scoured  at  the  source.   However,  this  fact  does  not  appear   to
significantly  affect  this  analysis  of  U.S.  raw wool scouring mills.
Note that scoured wool is often converted into "tops" at the same  mill.
In  this operation, the short fibers are separated mechanically from the
long ones; the long fiber "tops" are used for worsted yarn and the short
fibers are used to blend into woolen yarns.  No added pollution  occurs.
Water load is increased by air conditioning and air scrubbing.

Subcategory 2 - Wool Finishing

As  mentioned, the metallized dyes used for wool are very fast (i.e., do
not fade or rub off readily).  Hence on 100 percent  wool  cloth,  these
dyes  are  often  used.   In  the  blends,  however,  the  dyes used for
polyester and other synthetic fibers have poorer fastness,, so  in  these
blends  many  woolen  mills  have  converted  to  non-chrome dyes.  As a
result, an all-wool mill may be expected to have significant  chrome  in
its  effluent, but in a wool-blend mill, the chrome will be considerably
less or even non-existent.

Since many wool mills investigated are working  on  blends,  principally
polyester,  carriers  such  as orthophenol, phenol, diphenyl, or benzoic
acid derivatives will be present at  significant  levels  in  their  raw
wastes.   Phenolics appear to be losing favor because of their odor, but
current practice includes them and they will be present  in  most  wool-
blend mill wastes.

As a result of the above, the principal component that distinguishes tha
wool  mill  Subcategory  2  from  Subcategory  5, Knit Finishing, is the
chromium used to dye the wool.

The Subcategory 2 mills have a higher water usage rate  than  any  other
finishing  category.  The heaviest contributor appears to be the rinsing
after fulling.  The wet unit processes  are  described  in  more  detail
below.

Heavy Scour

Heavy   scouring  is the term applied to The washing of the fabric by the
use of  detergents, wetting  agents,  amulsifiers,  alkali,  ammonia,  or
various  other  washing  agents.   The purpose of this heavy scour is to
remove  oils, grease, dirt,  fulling solutions, emulsified oil,  lubricants
or any  other substances that are either introduced in  prior   processing
steps or that is carried to the finished  fabric from the raw stock.

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This  process  is  one  of  the  most  important steps in wool finishing
because if all of the foreign materials are not completely  washed  out,
the  finished  fabric  is susceptible to rotting, smelling,  bleeding and
will not accept dyes uniformly.

Fancy goods, in contrast to piece dyed goods, are only scoured prior  to
mechanical  finishing.   Piece  dyed  goods  on  the  other hand must be
scoured completely prior  ro  the  dyeing  step.   The  weight,  foreign
material  content  and degree of felting of the fabric all have a direct
bearing on the degree of scouring required.

Heavy weight, closely wcven fabrics with a high percentage  of  recycled
wool  reguire  very  heavy  detergents,  long  wash  times and extensive
rinsing to clean the goods.  High organic  and  hydraulic  loadings  are
associated  with  this  type  of  fabric.   Light  open goods with a low
percentage of wool generally scour more ea'sily with lighter  detergents,
shorter  wash  times  and  less  rinsing  resulting in lower organic and
hydraulic discharges.

Some mills produce both types of goods at the  same  time  and  relative
proportion  of each type will vary greatly causing great fluctuations in
organic hydraulic discharge.  Also some mills produce  only  light  open
goods  while others produce heavy, close woven fabrics.  The majority of
finished product weights range from 12 ounces per yard to 26 ounces  per
yard;  however,  because  of  the  differences  in raw stock and felting
requirements the hydraulic and organic discharges may differ greatly.

Carbonizing-  Carbonizing consists  of  soaking  the  fabric  in  strong
sulfuric acid, squeezing out the excess, and then heating the wet fabric
in  an  oven.   The hot acid reacts chemically with vegetable matter and
any cotton fiber contaminant and oxidizes these  contaminants  to  gases
and  a solid carbon residue.  The fabric is then passed between pressure
rolls where the charred material is crushed so that it may be  separated
by mechanical agitation and flowing air.  A solid waste is produced, and
the  acid  bath  is  dumped when it becomes too contaminated for further
use, about once every two days.

Fulling.  Fulling is usually used on 100 percent woolen fabrics but  not
usually  on  woolen/polyester  blends  and  not on worsteds.  Since this
operation stabilizes the dimensions of the wool  by  "felting"  it,  the
blends usually do not need it, nor do the worsted, since they are a very
tight  yarn  and  weave  to  begin  with.   Fulling  is  accomplished by
mechanical work performed on the greige goods while they are in  a  bath
of  detergent  and  water.  Detergent is added as needed but no effluent
occurs until the following washing step.  This is true of both "dry" and
"wet" fulling except that in the "wet" fulling, the water bath is dumped
about once every 2 to 3 days.  In "dry" fulling, just  enough  water  is
picked up by the fabric to lubricate it so the fabric is not standing in
water between its turn in the fulling device.

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The  fulling  is  followed by extensive rinsing to prevent rancidity and
wool spoilage.  This step produced over 50 percent of the hydraulic load
in an all- woolen mill investigated.

Crabbing.  Crabbing is the name given to the operation used to align the
fabric rectilinear ly.  Since the fabric comes in wet and goes  out  wet,
no effluent of significants occurs.

Pre-Scour.   The  pre-scour step is a final cleaning of the greige goods
prior to dyeing.  Often, if a light scour or fulling is performed before
dyeing, the pre-scour step is not used.  On sensitive  dyeing,  however,
both  light  scour  and  pre-scour  are  sometimes used.  Detergents and
wetting agents are added.  This and subsequent dyeing and rinsing  steps
are performed in becks.
          In t*ie dyeing process, the fabric is dyed in atmospheric becks
or pressure becks.  Pure wool fabric is dyed only in atmospheric  becks,
but  blends  (mostly  with  polyester)  are dyed in either atmospheric or
pressure becks.  Knit wcolen blend  fabrics  also  are  dyed  in  either
atmospheric  or  pressure  becks,  but  most  often they are dyed in jet
becks, a variation of the pressure  beck  that  is  supposed  to  reduce
physical damage to the knits.

In  conventional  becks  the  fabric  is  sewn  into  a  long  tube that
alternately soaks in a tube and then is  pulled  up  and  over  a  large
diameter  slatted  wheel.  In a jet beck the fabric is pulled up and put
back in the tub by the action of the dye liquor being pumped  through  a
venturi  and  carrying  the  fabric  with  it.  Pressurizing of becks is
desirable for dyeing the polyester portion of the fabric,  since  little
or  no carrier need be used.  At atmospheric pressures large quantitites
of carriers are required to swell the polyester fiber and enable the dye
molecules to penetrate.

In the dyehouse becks, the operation usually  consists  of  filling  the
beck  with  water  and  a  detergent  for scouring  (pre-scour, described
above) .  The scour water is dumped and the beck is refilled  with  water
and  a wetting agent.  After the fabric is wet-out, and the temperatures
raised somewhat, the dyestuffs are added and  the  beck  brought  up  to
temperature  ((100°C)  212°F  in  atmospheric  becks, higher in pressure
becks) .  After 2 to 4 hours, 90 percent or more of the dye is exhausted,
and the dye bath is discharged to the sewer.  This dye step is  followed
by  a  clear  water rinse.  Since the dyes are very expensive, effort is
made to assure as high an exhaustion level as possible.

Blends are sometimes dyed in a single bath, sometimes  in  two  separate
baths.   Therefore,  the  hydraulic  load  can  from  this  unit process
increase by 50 percent in the case of two baths (including a rinse  step
after all dyeing is completed) .
                                  50

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The  more  commonly  used dyes for wool (or the wool in wool blends)  are
metallized dyes and top and bottom chrome  dyes.   Others  used  include
reactive  dyes,  mill dyes, and others used for special effects.  Use of
chrome dyes is diminishing since their high fastness is  superfluous  in
wool  blends,  given  the  lower fastness of the dyes used for synthetic
fibers,  when wocl and synthetic fibers  are  blended,  therefore,  non-
chrome  wool  dyes of fastness equivalent to that of the synthetic fiber
dyes can be used in the interest of economy.

Rework levels appear to be 3 to 4 percent  of  total  production.   When
goods  are  reworked,  they  are  either  redyed  to  a darker shade, or
stripped with reducing chemicals, rinsed and redyed.

After it is dyed, the fabric is cooled with clear water and rinsed until
the dump or overflow water is clear.

Finishing.  After it is dyed and rinsed, the fabric is removed from  the
beck  and,  when  used,  soil  repellents and other finishing agents are
padded onto it.  Next, the  fabric  is  dried  and  any  subsequent  dry
finishing  operations -- principally shearing (solid waste)  and pressing
(steam condensate) -- are performed.

Mothproofing is accomplished with Mitten-FF for  government  fabrics  or
with  Dieldren  for certain other specialized fabrics.  Spillage appears
to be the only way this material might  find  its  way  into  the  waste
waters.

Any  of the finishing chemicals can appear in the waste when the padding
equipment is dumped and washed.

Subcategory 3 - Greige Mills

Waste at greige mills constitute residues in size boxes at the end of  a
day  or  a  week,  and  water used for clean-up.  The volumes of textile
wastes in a greige mill are small.  Significant amounts of water used in
a greige mill  (e.g., cooling water) may not enter  the  waste  treatment
plant.

A  typical  sizing formulation is composed of a film-forming material, a
fatty or waxy component, and water.   In  some  formulations,  a  water-
soluble  dye may be used to give the grey cloth an identifying color.  A
preservative may be used in some sizing mixtures.

The most common film forming materials are starch, polyvinyl alcohol and
carboxymethyl cellulose.  Other sizes,  such  as  polyacrylic  acid  and
styrene-maleic  anhydride  polymer,  are  used  occasionally  in weaving
special cloths.
                                  51

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Starch is a traditional sizing material,  but in the past  several  years
the  volume  of  polyvinyl  alcohol  used  in  the  textile industry has
increased substantially, since  starch  does  not  adhere  well  to  the
synthetic  hydrophobic  fibers.   In  many cases,  mixtures of starch and
polyvinyl alcohol are used.


When formulations based on starch are used, the add-on of  size  amounts
to  10  to 15 percent by weight or warp yarn.   When polyvinyl alcohol is
used, lower add-on, 3 to 8 percent by weight of the fabric, is  typical.
The  range  of add-on depends on cloth construction factors such as warp
yarn diameter, "tightness" of the faoric, etc.

The total waste load at a  greige  mill  is  typically  greater  tan  90
percent sanitary and the remainder is industrial.

Treatability  of greige mill wastes is relaxed to the size used.  Starch
is very readily degraded biologically, and may be  given  a  preliminary
enzyme  treatment  to  improve  biodegradability.    On  the  other hand,
polyvinyl alcohol is consumed by  organisms  relatively  slowly,  though
recent  studies show that organisms acclimate to polyvinyl alcohol. (See
Subcategory 4 below).

Subcategory 4 - Woven Fabric Finishing

The wastes associated with finishing woven goods result from removal  of
foreign material during the cleaning and from the various chemicals used
in finishing the fabric.

Desizing

Enzymatic  removal  of  starch size generates starch solids, fat or wax,
enzyme, sodium, chloride and wetting agent in the effluent, stream.   The
waste  contains dissolved solids  (both organic and inorganic), suspended
solids, and some fat or wax; it has a pH of 6 to 8,  is  light  colored,
and contains no toxic materials.

Sulfuric  acid  removal of starch size generates waste containing starch
solids, fat or wax and sulfuric acid.  It contains organic and inorganic
dissolved solids, suspended solids, and some oil and grease.  It  has  a
pH of 1 to 2 and is relatively light colored.

After  the  desizing  agent  has been applied, the goods are placed in a
bind or a steamer to provide the  residence  time  required.   Residence
time  in  storage  bins  are  typically  12  hours or more.  If elevated
temperatures are used by employment of J-boxes or steamers the residence
time is reduced to 30 minutes at  180 F or a few minutes at 210 to 212 F.
Finally, the goods are  washed  with  water  to  remove  the  decomposed
starches from the fabric.  Polyvinyl alcohol and carboxymethyl cellulose
                                  52

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are both removable with water alone.   The goods are washed with water at
180F  or  higher  on  washers  without  the use of steamers, J-boxes, or
padders.   Desizing  these  materials  will  thus  contribute  suspended
solids, dissolved solids and oil and grease.  Since these sizes are used
at  about  one-half  the  concentration  of  starch,  the  total  solids
generated in the waste stream are aJocut one-half the level corresponding
to starch use.  When mixtures of starch and polyvinyl alcohol are  used,
desizing  may  involve  the use of enzyme (to solubilize the starch)  and
water;  total  wastes  generated  would  be  intermediate  between  that
developed by either size used alone.

Desizing  may contribute 50 percent or more of the total waste solids in
a woven goods finishing mill.

The contribution of starch to BOD of waste streams has  been  documented
many  times.   On  the other hand, polyvinyl alcohol has been considered
very slowly biodegradeable, and as such, a major source of COD.   Recent
studies  performed by producers of polyvinyl alcohol in cooperation with
textile mills, indicate  that  biological  waste  systems  will  develop
organisms  acclimated  to  polyvinyl alcohol, and when this has occured,
biodegradation is relatively rapid and complete.

Scouring

Scouring is dene to remove much of the  natural  impurities  of  cotton,
using  2  to 3 percent sodium hydroxide; phosphate, chelating agents and
wetting agents may be used as auxiliary chemicals.  The synthetic fibers
require much less vigorous scouring;  scdium carbonate and  a  surfactant
may suffice.  In the case of cotton/synthetic blends, Varsol may be used
in conjunction with the aqueous scouring liquor.

The  operation  known as kier boiling is often employed to scour desized
cotton and cotton/polyester woven fabrics.  The kier is a large vertical
cylindrical pressure vessel  which  can  hold  up  to  several  tons  of
fabrics.  The goods  (in rope form) are plaited into the kier by the kier
plaiter,  the  covers  are  installed,  and  the  scouring chemicals are
recirculated through the  goods  and  an  external  heat  exchanger  for
temperature  control.   An aqueous mixture of sodium hydroxide, soap and
sodium silicate is  employed  at  temperatures  of  220  to  250  F  and
pressures  of  10 to 20 psig.  The goods are  scoured for 6 to 12 hours.
The kiers are then coded by recirculation  of  cooling  water  and  the
goods  are displacement washed.  In certain instances, difficult fabrics
are double-scoured.  The scouring step is designed to remove fats, waxes
and pectins from the woven fabric.

Certain heavyweight fabrics  normally  are  not  processed  in  rope  as
required  for kier boiling since creases result in streaks in subsequent
dyeing steps.  These goods are  therefore  processed  in  an  open-width
boil-out  maching, also known as the progressive jig.  The jig is loaded
                                  53

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with a scouring solution and the goods are fed through  continuously  by
coils  and  the temperature and residence time are maintciined for proper
scouring of the goods.  The goods are wound onto rolls  in  the  maching
and  maintained  in  contact  with  scouring  liquids  for the necessary
period.  Then they are unrolled through wash boxes  and  folded  into  a
cloth truck or onto a rcll.

The scoured cotton may be used directly for producing dark shades or may
be   bleached  by  padding  through  hydrogen  peroxide  solutions,  and
subsequently washed, neutralized, and dried before dyeing.

Scouring liquors are strongly alkaline (pH greater than  12),  and  dark
colored  due  to  cotton impurities.  They contain significant levels of
dissolved solids and oil and grease.  A modest level of suspended solids
results from the presence of cotton impurities.

The natural cotton impurities removed form  greige  fabric  by  scouring
contribute BOD and are fciodegraded rapidly.


Scouring  of  cotton/polyester greige blends generates the same waste in
proportion to the amount of cotton.

Scouring of synthetic woven goods generates a  low  level  of  dissolved
solids from surfactant, soda ash, or sodium phosphate.

Mercerization

Physically,  mercerization  swells  the  cellulose  fibers  as alkali is
asbsorbed into them, with higher concentrations, longer residence times,
and lower temperatures favoring  greater  swelling.   The  mercerization
step  is  conducted with the fabric either under tension or in the slack
condition,  with  tension  mercerizing  favoring  increases  in  tensile
strength   and   slack   mercerizing   favoring  increases  in  abrasion
resistance.

Mercerization is normally conducted continuously; the operation consists
of the following steps:

     (a)  A scutcher and water mangle are employed to open the goods
         from the rope form, and a mangle is used to deweiter
         the goods to a uniform moisture concentration.

     (b)  A multiple-contact saturating operation is conducted usually
         with three saturating bowls.  The goods are fed through the
         system continuously which provides sufficient residence
         time and contact to completely saturate the fabric with
         caustic soda solution.

-------
     (c)   Timing cans are employed to increase the residence time
         of the fabric in the sodium hydroxide solution.

     (d)   A tenter frame is employed to maintain the fabric under
         tension as the fabric travels through the system and the
         actual mercerization of the cellulose takes place.

     (e)   At the end of the tenter frame is a washing system that
         includes water sprays, vacuum units and wash water heaters
         and re-circulators to wash the fabric and reduce the caustic
         content while the fabric is still under tension in the
         tenter frame.

     (f)   The fabric is given a final wash in the recuperator, which
         removes the remainder of the sodium hydroxide from the
         fabric and reduces the residual pH to an acceptable level
         (i.e. , 8.5) .

Mercerization wastes are predominantly the alkali used in  the  process.
The waste stream contains high dissolved solids, and may have a pH of 12
to  13.    The  BOD  level is low due to a penetrant used as an auxiliary
with the caustic.  Small amounts of foreign  material  and  wax  may  be
removed  from the fiber, and will appear as suspended solids, and wax in
the wastes; these materials will contribute a small BOD load.

In large mills, caustic soda is recovered and concentrated  for  re-use,
thus,  saving  chemical  and  avoiding a sizeable waste load.  Estimates
have indicated that recovery of mercerizing caustic  is  justified  when
the  caustic  use  is  more  than  5  million pounds per year (dry) , and
concentration of the alkali is not permitted to fall below 2%.

Bleaching

The following process units constitute a  typical,  continuous  peroxide
bleaching range, using J-boxes for storage:

Wa sh ing .   The goods are washed, using either open width or rope washers
to ensure removal of converted starches from the desizing step.

Caustic Satura tor.  As the goods continuously leave the washer they  are
squeezed  through  rolls  to  a minimum water content and then saturated
with sodium hydroxide solution in additional squeeze rolls.   The  goods
may  be  in  either  rope  or  open  width  form, but must remain in the
saturator long enough to permit them to become completely saturated with
sodium hydroxide solution.
                    goods are then fed continuously to  the  caustic  J-
boxr whose function is to saturate the cloth for the necessary length of
time at the desired temperature (205-210F).  The throughput of the J-box
                                  55

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is controlled to provide a residence time ranging from 40 minutes to one
hour,  resulting  in saponification of natural fats and waxes carried in
the cotton.

Caustic Washers^  The caustic solution is then removed from  the  fabric
by countercurrent washing, usually with large quantities of hot water to
ensure complete removal.

2®£22£i
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           Width J-Boxes^  More recent bleaching technology employs more
concentrated  solution  and  more  drastic  operating conditions and has
resulted in the development of the small open width J-box which  permits
effective bleaching with residence times of only 10 to 15 minutes.

Contjnous  Pressure  Scouring and Bleaching.  The newest type of steamer
for bleaching ranges is an enclosed type with pressure locks and  seals.
This  enables  the  steamers to be operated as a pressure vessel and the
reaction time for the chemical is reduced from 40 minutes to only one to
two  minutes.   The  treatment  of  fabrics  is  a  function  of   time,
temperature and concentration.  The increased temperatures made possible
by  pressure  steamers  reduce  the  time  needed  for complete chemical
reaction.

The problem associated with equipment designed for operation at 25  psig
and  for  continuous  entry  and removal of continuous webs have posed a
substantial design problem.  However, several machines are now available
with satisfactory sealing devices, so they may  perform  well  at  these
pressures.  some of these units utilize rolls as a sealing mechanism and
others  have developed a system involving a lip seal.  In addition there
are reports of pressure steamers which may be operated at  pressures  up
to  45  psig  and  develop  temperatures of 292F, resulting in residence
times only of one or two minutes.

Sodium chlorite Bleaching^  Although sodium chlorite bleaching  has  had
very  little economic success in the bleaching of pure cotton goods over
the years, its use in kier steamers and  becks  is  now  receiving  more
attention  since  many of the man-made fibers are sensitive to bleaching
and can be bleached successfully with sodium chlorite.  It is  now  used
to   a  considerable  extent  either  alone or in conjunction with other
bleaching agents for preparation.

Bleaching with hydrogen peroxide contributes  very  small  waste  loads,
most  of  which  is  dissolved  solids.   The  dissolved solids are both
inorganic (sodium silicate, sodium hydroxide and sodium  phosphate)  and
organic  (a surfactant and chelating agent).  The waste stream contains a
low level of suspended solids when goods containing cotton are bleached.

Dyeing

Dyeing  is the most complex of all textile finishing processes.  Table 8
shows the dyes used  in  the  textile  industry,  the  fibers  they  are
generally  used  to  color, and the relative amounts of each dye used by
the industry.
                                  57

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When textiles are dyed, an excess of the dyestuff  is  used,  and  other
chemicals  are  used  to  help deposit the dye, or to develop the color.
Dye loadings vary widely even with a particular dye class, depending  on
the weight of fabrics being treated and the depth of color desired.  The
range  of  chemicals employed in dyeing also varies widely from place to
place and operation to operation, and  depends  substantially  upon  the
dictates of the marketplace.

Table  9  presents a summary of chemicals used in application of dyes to
textiles.  Dyed goods are generally, but not always, washed  and  rinsed
to remove excess dye and chemicals from the cloth.  Washing involves use
of  a  detergent,  and  also may involve the use of soda ash or a sodium
phosphate.

The chemical used in dyeing  may  depend  significantly  on  the  dyeing
procedure  which the fabric manufacturers finds appropriate.  Both batch
and continuous dyeing are practiced, and both may  be  employed  in  the
same finishing plant.

Textile  goods  are dyed continuously when the demand for a single shade
is sufficiently high to justify the necessary equipment.  Production  of
denims,  in  which the warp yarns are dyed continuously, is one example;
no special chemicals are required as a result of dyeing continously.  In
Thermosol dyeing,  which  is  practiced  on  woven  cotton  (or  rayon),
polyester  blends,  a  dye  blend is padded on the fabric, which is then
dried and heated, washed and dried.  Thermosol dyeing requires  addition
of  a  gum  to  the  dye  mixture,  so that the formulation will deposit
uniformly on the cloth.

Piece dyeing, on runs which are not long enough  to  justify  continuous
processing,  are normally performed in an open beck, operated at boiling
temperature, or in a sealed pressure beck, operated at about  250F.   in
modern  units,  the  entire dye cycle (including washing and rinsing) is
controlled automatically.  Pressure becks have been  found  advantageous
use of less carrier; wastes are decreased correspondingly.

Dyeing  processes  contribute substantially to textile wastes.  Color is
an obvious waste.  A high level of dissolved solids is expected.

Suspended solids should be  low.   Carriers,  which  are  essential  for
dyeing  polyester  and  acetic acid, have high BOD.  Sodium hydrosulfite
has a high immediate oxygen  demand.   Plants  using  sulfur  dyes  will
contain  sulfides  in the raw waste, and dichromates may be a waste when
vat dyeing is practiced.

Some of the wastes from  dyeing  textile  fabrics  are  related  to  the
production  equipment  and to the size of the mill.  On long runs, where
continuous Thermosol dyeing of synthetics or  synthetic  blends  can  be
                                  59

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justified,  carriers  may  be  avoided;  a  gum  will  be used, and will
contribute a low BOD.

Table 9 shows alternative chemicals that may be used as substitutes  for
sodium  dischromate.   Controls  are  available for the reduction of vat
dyes and their reoxidation; use of the controls will minimize wastes.


Printing

Printing involves application of dyes or  pigments  in  the  form  of  a
pattern  on to fabric.  Dyes penetrate and color the fiber; pigments are
bonded to the fabric with a resin.  In  general,  the  formulated  print
paste is applied to one side of the fabric only.

Vat,  direct  and other dyes may be printed; vats appear to predominate.
The same chemicals used for the  regular  dyeing  process  are  used  in
printing,  but in addition, a thickener is used to give the mixture high
viscosity.  Many thickeners such as gum arabic, British gum,  alginates,
methyl cellulose and others have been used.  Urea, diethylene glycol and
glycerol are frequently used in the formulations.

Pigment  print  formulations are more complex.  The pigments are blended
with a resin binder   (frequently  melamine-formaldehyde),  a  latex,  an
aqueous thickener, Varscl and water.
                                   60

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                                Table_9

                 ChemicalsjUsed_in Application of Dyes

                                   Auxiliary Chemicals ^ece
Vat
Direct
Disperse
Sulfur
Acid
Cationic
Reactive
sodium hydroxide
sodium hydrosulfite
  di spe r s i ng a gent
  hydrogen peroxide
  acetic acid
  sodium perborate alternative
  sodium dichromate chemicals
  acetic acid

  sodium chloride
  sequestering agent

  orthophenyl phenol  alternative
  butyl benzoate   carriers
  chlorobenzene
  acetic acid
  mono sodium phosphate
  dispersing agent

  sodium sulfide
  sodium carbonate
  sodium dichronate
  acetic acid    alternatives
  hydrogen peroxide
  acetic acid

  acetic acid
  ammonia sulfate of
  ammonia acetate
  sodium chloride

  acetic acid or
  formic acid
  sodium sulfate

  sodium chloride
  urea
  sodium carbonate
  sodium hydroxide
                                  61

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                          Table ,9	(continued)

                 Chemicals Used in Application, of Dyes1

Dye Type                           Auxiliary^Chemiqals^NecessarY

Developed                                     developer
                                       sodium chloride
                                       sodium nitrate
                                       sulfuric acid
                                       sodium carbonate

1(In addition to the chemicals listed, all of the dye types will usually
use  a small amount of surfactant.  After the dyeing has been completed,
the dyed goods are washed and then rinsed.  Washing will involve use  of
a detergent as well as soda ash and a phosphate.)


Vat  dye  prints  must  be  oxidized,  with  sodium  dichromate or other
oxidants, to develop the color.  Steaming and brief  aging  aid  in  the
process.   Pigment  prints  do not require chemical after treatment, but
must be dried and heated to insolubilize the resin-pigment mixture.

Printing a fabric that contains polyester may require a carrier  in  the
formulation.

Following  complete  application  of  the  print  mixture, the fabric is
washed thoroughly to remove excess color and chemical.

Printing wastes are comparable in many respects to dye wastes.  Printing
requires use of gums, which will contribute BOD.  Solvents  (Varsol)  and
glycerine  are also common constituents in printing, but pose no special
waste treating problem.  Printing pigments will introduce some suspended
solids into the waste.  Much of the  wastes  from  printing  comes  from
cleaning  of  make-up  tanks  and  process  equipment.  These relatively
concentrated  wastes  may  justify  segregated  treatment,  perhaps   by
incineration.

Other_Treatment Wastes

Special   finishes  such  as  resin  treatment,  water  proofing,  flame
proofing, and soil release endows the fabric with a particular  property
desired by consumers.  The property is indicated by the name, except for
resin   treatment,   which  designates  finishes  that  provide  wrinkle
resistance.  Several of the treatments may  be  applied  from  a  single
bath.

As  would  be  expected for processes that provide such diverse effects,
the range of chemicals used is very broad.  For resin treatment, a urea-
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formaldehyde-glyoxal  compound'  ("DMDHEU") ,  a  fatty  softner,   and   a
catalyst  (zinc  nitrate,  magnesium chloride)  are used together.  Water
repellents include silicones, fluorochemicals, and fatty materials, each
generally applied with a  catalyst.   Soil  release  treatments   include
special acrylic polymers and fluorochemicals.

These  finishes  are  generally  applied  by  impregnation of the fabric
followed by squeezing to the desired  add-on.   The  moist  material  is
dried and then cured by additional heat.  The cured fabric is frequently
packed  for  shipment  without  rinsing.   Most  resin-treated goods are
subsequently cured in a garment factor and must not be rinsed, since the
catalyst would be removed.

Wastes from resin treatment,  water-proofing,  flame-proofing  and  soil
release  are small, since the chemicals are applied by padding,  followed
by drying and curing.  The chemicals used are diverse and small   amounts
of them will enter the wastes.

Subcategory 5 - Knit fabric Finishing

Typically,  knits  are processed in piece goods form.  The fabric may be
washed on continuous countercurrent washers prior to loading the  fabric
in  dye  machines  to  remove  knitting  oils and other contaminents, or
washing may be the first step in the dye machine cycle.  Warm water with
a small amount of added detergent is used.    In  contrast,  woven  goods
require more extensive treatment to remove starch or polymeric sizes.

The  types  of  dyeing equipment generally employed include: atmospheric
becks, pressure becks, jet  (atmospheric or pressure)  becks,  atmospheric
or pressure beam dyeing machines,  and paddle type machines.  Some plants
may also package dye a portion of their yarns.

The  types of dyestuffs, auxiliaries, and conditions employed for dyeing
knit goods are essentially the same as for  woven  goods  of  comparable
fiber  composition.   See the discussion under subcategory 4 for details
of the dyeing operation.

Some of the fabrics which are beam dyed are first wet batched.   In  the
wet  batching  operation,  the fabric is passed through a dilute aqueous
surfactant bath at controlled  temperatures  before  being  wound  on  a
perforated  beam.   Batching  helps  control  shrink and yield,  and also
enchances penetration of dye liquors in the dyeing  process.   There  is
some  waste generation from the wet batching operation; a small  quantity
of the dilute bath is dumped occasionally for cleanup  and  there  is  a
continual  slow  drain  of  water  from the wetted fabric which  contains
knitting and yarn lubricants.

In knit plant, finishing  cotton  fabric  —  e.g.,  for  underwear  and
sleepwear  — wet process operations also include scouring and bleaching
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in kiers or comparable equipment.   Plants that process either cotton  or
synthetic goods may alsc have fabric printing operations.

Most  knit fabrics are treated with softners, and resin finished,  and in
some cases, with water and oil repellents.  These finishes  are  applied
from a pad bath just prior to final drying and dry finishing operations.
These  baths  are  discharged  periodially as required for fabric lot or
formulation changes, but the total daily volume of  discharges  is  very
small.

The  main  difference  between  knit  and  woven  fabric  wet processing
operations are that knit yarns are treated with lubricants  rather  than
with  the starch or polymeric sizes used for woven goods yarns, and that
mercerizing operations are not employed with knit goods.  Otherwise, the
character of  the  wastes  generated  frcm  comparable  unit  operations
performed  on  different  fibers—cotton,  synthetics,  and  blends—are
similar to those found in woven fabric finishing.

Lubricating finishes applied to knitting yarns generally  are  based  on
mineral  oils,  vegetable oils, synthetic ester type oils, or waxes, and
may also contain antistatic  agents,  antioxidants,  bacteriostats,  and
corrosion  inhibitors.   Specific  formulations are proprietary with the
yarn suppliers or throwster who applies the finish.  The aimount  applied
varies with the type of yarn; general levels of add-on by weight percent
on  yarn  are: untexturized synthetic yarns, 1 and 2 percent; texturized
synthetic yarns, 4 to 7 percent; and cotton yarns  3  percent  or  less.
These  knitting oils are readily emulsified or soluble in water, and are
removed by washing prior to the dyeing operations.

Subcategory 6 - Carpet Mills

The carpet industry wastes are very similar  in  nature  to  those  from
Subcategory 5, Knit Goods.  When polyester is dyed, the carriers present
the  same  problem  as in other categories, but very little polyester is
being used or will be used until a satisfactory answer  to  fireproofing
is   found.    Therefore,  the  nylon,  acrylic  and  modacrylic  dyeing
predominate.  This means very little phenolics from carriers,  and  very
little chrome from wool dyeing.  Spin cils from the yarns are present.

A special waste, peculiar to this industry, exists because of the use of
foamed  and  unfoamed  latex backing.  The latex is not soluble in water
but is used in a highly dispersed form; hence suspended solids  and  COD
could  be  a  problem  unless  they  are  coagulated.  This stream  (from
equipment washdown once a day to once a  week)  is  usually  segregated,
acidified  to  hasten  coagulation, and settled before it joins dyehouse
wastes.

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Municipal treating plants require pretreatment of the carpet mill wastes
to remove fibers and latex.  Any latex that enters the sewer lines tends
to form strings and can cause appreciable deposits.

The pH of carpet wastes is usually close to neutral.

With the lack of other wet processing steps in the  mill,  the  hot  dye
wastes sometimes  present a problem to biological treatment systems.

The color problem is siirilar to that of ether finishing categories.

Where carpets are printed, the thickeners present a high BOD load, as in
fabric printing.

Subcategory 7 - Yarn Eyeing and Finishing

Wastes  generated in yarn processing plants will depend substantially on
whether natural fibers, blends, or synthetics alone are processed.

When synthetics alone are handled, only light scouring and bleaching  is
required, and wastes would be low levels of detergents, soda ash, sodium
phosphate,  and  perhaps a low bleach level.  Wastes for this step would
have low BOD, and dissolved solids.  Dyeing would contribute a  stronger
waste,  primarily  due  to  the carrier in the case of polyester, and to
some acetic acid; wastes, of course, would contain some color.

Scouring, bleaching, and mercerizing of cotton generate  BOD  and  color
because  of  the  fiber  impurities,  and high level of dissolved solids
because of the mercerizing.   Because  of  the  relatively  low  amounts
involved, it does not appear reasonable to recover caustic soda.
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                               SECTION VI

                   SELECTION OF POLLUTANT PARAMETERS

WASTE WATER,PARAMETERS^.OF MAJOR^SIGNIFICANCE

A  thorough  analysis of the literature, industry data and sampling data
obtained from this study, and EPA  Permit  data  demonstrates  that  the
following  waste  water parameters are of major pollutional significance
for the textile industry:

Biochemical Oxygen Demand (5-day, 20° C., BOD5)
Suspended Solids  (SS)
pH
Chemical Oxygen Demand  (COD)  - (Large plants)
Fecal Coliforms
Grease and Oil  (Subcategory 1 - Raw Wool Scouring)

Ratignale_f Qr_Selection.. of MalQr_Parameters

Biochemical Oxygen Demand

This parameter is  an  important  measure  of  the  oxygen  utilized  by
microorganisms in the aerobic decomposition of the wastes at 20°C over a
five  day  period.   More  simply,  it  is  an  indirect  measure of the
biodegradability of the organic pollutants in the waste.   BOD_5  can  be
related  to  the  depletion  of  oxygen  in a receiving stream or to the
requirements for waste treatment.

If the BOD5 level of the final effluent of a mill into a receiving  body
is too high, it will reduce the dissolved oxygen level in that stream to
below  a  level  that  will  sustain most fish life; i.e.  below about 4
mg/1.  Many states currently restrict the BOD5 of effluents to below  20
mg/1 if the stream is small in comparison with the flow of the effluent.
A  limitation  of 200 to 300 mg/1 of BOD5 is often applied for discharge
to municipal sewers, and surcharge rates often  apply  if  the  BOD5_  is
above the designated limit.

Concentrations  of  BOD_5 in the raw wastes may vary from 50 mg/1 to 3000
mg/1.  The values depend on the fibers processed,  the  chemicals  used,
and  on  processing methods.  The oxygen demanding portion of the wastes
are treatable biologically, with only a few  exceptions.   The  use  and
degree of removal in a given time are quite variable.
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Suspended Solids

This  parameter measures the suspended material that can be removed from
the waste waters by laboratory filtration, but does not  include  coarse
or  floating  matter  than  can  be  screened  or  settled  out readily.
Suspended solids are present in textile waste waters as a process  waste
generated  from  the  fibrous  substrate,  the  chemicals  used, and the
biological treatment.  Most of the solids may be removed in  clarifiers,
in  settling  basins,  by filtration, or by other techniques.  Suspended
solids are a visual and easily determined measure of pollution and  also
a  measure  of  the  material that may settle in tranquil or slow moving
streams.  A high level cf suspended solids  is  an  indication  of  high
organic pollution.

PH

The  variations  in pH cannot be characterized across the industry since
some  processes  require  highly  acid  conditions  and  others   highly
alkaline.   Neutralization is practical where pH control is necessary to
prevent adverse effects in biological waste  treatment  systems.   These
systems operate effectively at a pH range between 6.0 and 9.0.

Chemical Oxygen Demand  (COD)

COD  is  another  measure  of  oxygen demand.  It measures the amount of
organic and some  inorganic  pollutants  under  a  carefully  controlled
direct chemical oxidation by a dichromate-sulfuric acid reagent.  COD is
a  much more rapid measure of oxygen demand than BOD^ and is potentially
very useful.

COD  provides  a  rapid  determination  of  the  waste  strength.    Its
measurement  will indicate a serious plant or treatment malfunction long
before the BOD5 can be run.  A given plant  or  waste  treatment  system
usually  has  a relatively narrow range of COD:BODj5 ratios, if the waste
characteristics are fairly constant, so experience permits a judgment to
be made concerning plant operation from COD values.  COD limitations are
to be applied only to the large plants.

Fecal Coliforms

Microbiological  testing  for  the  presence  of  fecal  coliforms  will
indicate  the  potential  for  the  waste  water  to  contain pathogenic
bacteria.   Sanitary  sewage  is  a  component  of  many  textile  waste
treatment plants, and is often desired for its nutrient value.
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Grease and oil

Wool wax is a substantial pollutant in the wool scouring subcategory;  in
other  textile subcategories,  other materials measured as grease and oil
are much less troublesome.

Rationale for Selectign_of Jginor^Parameters

Total Dissolved Solids (IDS)

The dissolved solids in waste  water are mainly  inorganic  salts.   They
are   particularly  important   as  they  are  relatively  unaffected  by
biological treatment processes and can accumulate in water recirculation
systems.  Failure to remove them may lead to an increase  in  the  total
solids  level of ground waters and surface water sources.  The dissolved
solids in  discharge  water,   if  not  controlled,  may  be  harmful  to
vegetation and may also preclude various irrigation processes.  There is
not sufficient data available  to establish effluent limitations for TDS,
but at land treatment systems  TDS must be managed to insure satisfactory
performance  without damage to the physical properties of the soil or to
the quality of the ground waters.

Alkalinity

The measure of alkalinity is  an indicator of bicarbonate, carbonate  and
hydroxide  present  in the waste water.  The alkalinity of water appears
to have  little  sanitary  significance.   Highly  alkaline  waters  are
unpalatable,  and  may adversely affect the operation of water treatment
systems.  However, pH limitations require the control of alkalinity  and
thus no alkalinity limitations are needed.

Ammonia Nitrogen and Other Nitrogen Forms

The  three  most common forms  of nitrogen in wastes are organic, ammonia
and nitrate.  Organic nitrogen will break down  into  ammonia,  nitrogen
and  nitrate,  when ammonia nitrogen is present in effluent waste water,
it may be converted to nitrate nitrogen by oxidation.  When ammonia  and
nitrates   are   added   to   ponds   and   lakes,  they  contribute  to
euthrophication.  Additions of ammonia or urea as a nutrient to nitrogen
deficient waste is a common practice in the industry.

Phosphates

Phosphorus like nitrate is linked directly to the eutrophication process
of lakes and streams.  When applied to soil, phosphorus does not exhibit
a runoff potential because it is readily absorbed  tenaciously  on  soil
particles.   In  this  case,   movement  of phosphorus to ground water is
essentially precluded and runoff can only occur if actual erosion of the
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soil takes  place.   Phosphates  may  also  be  added  as  nutrients  to
biological treatment systems.

Temperature

The  temperature  of effluent waste water is important, since release of
water at elevated temperatures into surface or ground  water  formations
could result in damage to the micro-ecosystems.  The design of treatment
facilities  is  also dependent upon the plant effluent temperature.   Raw
waste from many textile mills is  hot,  but  the  temperature  reduction
occurs  naturally  in  waste treatment, and the temperature of the final
effluent should be very close to  ambient.   Therefore,  effluent  water
temperature does not present a problem.

Color


Color  is  found throughout the textile industry.  Some colors are water
soluble and some are not  (dispersed dyes) .  Biodegradability  is  highly
variable.  Many hues are used in dyeing, and may appear in wastes; their
combination in waste streams frequently generates a gray or black color.
As  a  pollutant parameter, color is an aesthetic rather than a toxicity
problem,  and  there  is  no  universally  accepted  monitoring  method,
although several techniques are being tried.

Chromium

selection  of chromium as a pollutant parameter is based on its wide use
as an oxidant in the form of sodium dichromate for vat and  sulfur  dyes
and as a component of wcol dyes.  Substitutes are available, and several
mills  are abandoning its use, but it is still widely used.  Chromium is
the most significant heavy  metal  in  the  textile  industry,  although
others are employed selectively.

Other Heavy Metals

Copper  salts  are  still  used in some dyeing operations of the textile
industry.  Since it is harmful  in  biological  systems,  it  should  be
considered  as  a  pollutant.  Zinc nitrate is widely used as a catalyst
for durable press goods, and small amounts  will  enter  waste  systems.
Magnesium  chloride  may  be  used  in  the  same  process.  Mercury was
considered because of its known occurrence  in  raw  materials  such  as
sodium hydroxide which is used in large amounts by the textile industry.
In  normal  operation,  we  would  not expect the concentration of these
materials in the waste water to exceed harmful limits.
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Phenols

Phenols are widely used as carriers  in  dyeing  polyester  and  blends.
Some dye compositions  (naphthols)  will probably analyze as phenols also.
In  addition, some natural materials, such as lignin residues removed in
scouring cotton, probably analyze as phenols.

Sulfides

Since sodium sulfide is used in one type of  dyeing,  and  other  sulfur
containing  chemicals  are used, it was presumed that sulfides should be
considered among the parameters.   Small  amounts  of  sulfides  may  be
generated in processing wool.

Toxic Organic Chemicals

Dieldrin,  a  moth  proofing agent used for carpers would fall into this
grouping,  but  this  chemical  is  no  longer  used.   Some   carriers,
particularly chlorinated benzenes, are toxic and should not be used.
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                              SECTION VII

                    CONTROL AND TREATMENT TECHNOLOGY
The technology for control and treatment of waterborne pollutants in the
textile  industry  can  be divided into two broad categories: in-process
and end-of-pipe.  In-process control of waterborne  pollutants  in  turn
depends upon two major conditions:  (1)  altering the process requirements
that  generate water pollutants, and (2)  controlling water usage in non-
process as well as process areas.  For example, pollutants can often  be
kept from entering waste water streams through the institution of better
housekeeping  procedures, containment of leaks and spills, good mainten-
ance  practices,  and  the  segregation  and   treatment   of   selected
concentrated waste water streams.

At  present,  the textile industry is concerned principally with end-of-
pipe treatment of its waste waters.  However, the application  of  waste
water  treatment  technology  has often been instituted without detailed
investigation of the alternatives to water and  waste  water  management
within  the  process operations.  This approach, of course, is a natural
one to follow since institution of in-process changes for  an  operating
plant  is  frequently  time  consuming  and expensive.  Furthermore, the
incorporation of in-process control  of  waterborne  pollutants  demands
attention  to  specific  operations  which are often proprietary whereas
end-of-pipe waste water  treatment  technology  is  based  on  generally
similar  principles  which  are  available  from  consultants, equipment
manufacturers and the company's own competitors.

The textile industry relies principally upon biological treatment of its
waste waters at the end-of-pipe.  A large number of  plants,  especially
small  ones,  send waste waters into municipal sewage systems where they
may be a minor portion of the total flow; however, in some instances the
waste water flow to a municipal plant is predominantly waste water  from
textile plants.

In Process Control

Ancillary	Process __ Control  Technology.    A  big portion of the textile
waste loads is  inherent  in  the  methods  of  textile  processing  and
independent  of  the  efficiency of the processing plants.  For example,
size is applied to warp yarns to give them mechanical  strength  in  the
weaving operations; all of this size must be taken off before subsequent
bleaching  and  dyeing.   A  finishing plant can use variable amounts of
water in removing this size, but the raw  waste  load  due  to  size  is
unchanged.   The  same applies to spinning finishes on synthetic fibers,
which are put on the yarn as a lubricant and to  reduce  static  in  the
high-speed  spinning  and  textile operations.  All of these "temporary"
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finishes must be removed before dyeing of the yarn,   so  again  the   raw
waste load is almost independent of scouring efficiency.

On  the other hand there are many unit operations which are dependent on
chemical concentrations to provide desired effects.   The raw waste loads
of pollutants produced by these processes can be  substantially  reduced
through  water  reduction.   A plant can also reduce the other raw waste
loads—such  as  spills,  reworks,  etc.—in  many  ways.    These   are
considered below.

The  principal  axiom in reducing the waterborne pollutant loads through
control external to the process is to prevent pollutants  from  entering
the water streams.  Although this seems obvious, its successful applica-
tion  requires  continual attention by operating personnel.  In fact, it
is synonomous with creation of an effective work safety program.  In the
textile industry, with its large number of batch operations, one of  the
most important aspects of reducing waterborne pollutants is to institute
an effective water management program--including expanded use of liquid-
level-controls, flow  indicators  and  flow meters, adequate capacity for
generating hot water for wash operations, etc.--in  conjunction  with  a
good  maintenance  program  which  will  insure  that leaks from valves,
pipes, pumps, etc., are promptly  repaired  so  as  to  prevent  process
fluids  from  entering  floor drains, etc.  Except for subcategory 1 the
concentration levels of pollutants at  the  inlet  to  the  waste  water
treatment  plants  are not excessively high for industrial waste waters.
Consequently, a  significant  reduction  in  hydraulic  capacity  should
normally  effectively  lower  the  total emitted pollutants from a given
waste water treatment plant even  if  the  concentration  level  in  the
effluent  rose  moderately.   Obviously,  if  process  operations can be
changed to reduce the pollutant load to the waste water treatment  plant
simultaneously with a reduction in hydraulic flow the emitted pollutants
will be reduced even more.

Procedures  and  methods  for  preventing spills and leaks should be the
paramount consideration, but passive systems  for  containment  or  pre-
venting  their  entry  into  water courses should be part of any control
plan.  Only through assessment of the potential for pollutants to  enter
water  streams from accidential occurences and the development of action
plans is it possible to develop a high degree of assurance that  spilled
liquids will be prevented from polluting water courses.

In  summary,  strict  attention  to  housekeeping procedures and process
operation, can minimize abnormal waste loads.

conventional Processing_With_Better_Viater Economy The greatest potential
for improved water economy in the textile industry stems from the use of
better washing methods.  About 80 percent  of  all  the  water  used  in
textile  wet  processing  is  used for removing foreign material—either
that carried on the raw fiber,  or  materials  resulting  from  treating
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operations such as sizing,  scouring,  dyeing and finishing.   Furthermore,
most  applications  of treating materials are already carried out at low
liquor ratio for the sake of material and time economy.   It follows that
important water economies in conventional processing  can  be  made   by
reducing the amount of wash water.


Water usage can be improved substantially as design engineers take water
economy  into more active consideration.   For example,  so-called "double
laced" box washers have recently been introduced, with  claimed  savings
of  up to 40 percent in a number of machines.  Significant water savings
are claimed, but detailed quantitative data  are  not  available.   More
complex   open-width   washing   machines  designed  to  induce  greater
turbulence, have been offered without great success.  Since the physical
aim to be accomplished is clear, i.e., breaking down an effective  thick
diffusion  film  in  the  fabric  interstices,   it  is likely that more
efficient open-width machines can be developed.

Rope washers generally are more effective than open-width  washers,  but
may  be  susceptible  to  further  improvement  if  back-mixing  can  be
controlled in a practical manner.

In addition to better washer design,  there are opportunities  for  water
economy  in  more  counter-current  flows.   A  finishing plant operator
prefers to use fresh water at every machine, for  ease  of  control  anc?
adjustment,   and   for  freedom  from  danger  of  cross-contamination.
However,  some  opportunities  for  counter-flow  are   neither   unduly
difficult  nor  hazardous  to quality.  For example, it is almost always
acceptable to counter-flow water from machine to machine  where  several
machines  are  used  in  series  at  the same point in the process.  For
example, it is common to use 5 or 6 or more open-width  box  washers  in
series  after  scouring or mercerizing operations, or two Tensitrol-type
rope washers after scouring operations.  It is best for water economy to
counter-flow the water through the series.  This is frequently  but  not
universally  practiced  today.  Furthermore, it is practical to counter-
flow water from some later stages to seme earlier stages.  For  example,
white  washer  effluent  can  almost certainly be used as feed water for
caustic washers.  Additional opportunities for backflow  of  water  also
exist.    However,   there  are  limitations;  wash  wat€?r  from  dyeing
operations,  for  example,  always  contains  color,  and  is  generally
unsuitable  for re-use without cleanup.  Caustic scour and desizing wash
waters are  heavily  laden  with  dissolved  and  suspended  solids  and
unsuitable for re-use.

In  principle, water cleanup could be used around particular machines or
groups of machines, thus extending water economy  still  further.   Pre-
liminary  consideration of investment and operating costs indicates that
rhis is generally less economical than pooling effluents and  operations
of  one large treating plant.  Closing of water cycles around individual

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operations or groups of operations will  probably  be  limited  to  very
special circumstances.

In   summary,  further  water  economies  can  be  achieved  by  machine
improvements and by wider use of countercurrent flow.

New Process Technology

Solvent Processing : Serious study  of  textile  processing  in  organic
solvents  dates  back  at least 15 years, although batch applications of
special finishing, such as water repellents has been practiced for  more
than  a  generation.   In  the late 1950's, Imperial Chemical Industries
pioneered a solvent system  for  continuous  scouring  of  cotton  piece
goods.   Several  large  machines of this type have been operated in the
United States at various times since 1960.  During the 1960's, a  number
of  continuous  solvent  scouring  and finishing ranges were devised and
tested in Europe.  In most of these cases the development work has  been
carried out by solvent suppliers or equipment manufacturers.

In the course of this wcrk it has become clear that chlorinated solvents
such   as   perchloroethylene   and   trichloroethylene   are  the  most
advantageous materials now available.  It has  also  become  clear  that
suitable  machines can be manufactured and operated so as to control air
pollutions ir. the work space.  Solvent less remains an economic problem.
Extremely tight control is needed to keep  solvent  loss  per  operation
below  5  percent  of  fabric  weight.   To  date,  there  has  been  no
appreciable  commercial  use  of  solvent  finishing  for  woven  goods.
However,  solvent  processing  has  established  a  firm  if specialized
position in knit  fabric  finishing,  especially  in  the  finishing  of
synthetic knits.

Solvent  processing  has found commercial use only where superior fabric
properties have been achieved.  For  example,  solvent  applications  of
stain  repellent  finish  to upholstery and drapery materials are widely
practiced.  In this case, aqueous  treatment  is  not  always  possible,
because  the  fabric is sensitive to water.  Similarly, solvent scouring
and finishing of synthetic knit fabrics is widely practiced  because  it
is, in these cases, advantageous to quality to avoid wetting with water.
Some  finishes,  furthermore, are not available in water soluble or dis-
persible form and can be used only in solvents.

On the other hand, very substantial research and development efforts  in
the  last decade or so have not led to replacement of aqueous processing
to any appreciable extent.


Adoption of a complete solvent processing scheme avoids the  problem  of
dealing  with both aqueous and solvent wastes.  As noted above, however,
a complete line of textile  processing  and  finishing  compounds  would
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first  be required.  Some thousands of different dyestuffs and chemicals
are now used in commercial textile processing.   Only  a  limited  number
can be directly transferred to solvent use.

On the grounds noted above, it is becoming clear that solvent processing
generally  will be introduced only as superior results are demonstrated.
In general, this implies  better  properties  in  the  finished  fabric,
although  processing  advantages  may  lead the way in a few cases.   The
prospects for solvent processing are outlined below for each of  several
important finishing steps.
Solvent	Scouring	of	Woven	Fabric.    Despite  intense  effort solvent
scouring of woven  fabrics  has  not  established  a  firm  place.    The
properties  of  solvent scoured fabrics are not generally superior.   The
wastes generated are the same with respect to organic content,   but,   of
course, free from the alkali generally used for aqueous scouring.

Solvent	Scouring  of	Knit  Fabric.  Solvent scouring of some  synthetic
knit fabrics is well established and growing.  Commercial use  is  based
on superior results, fast drying  and easy extension to specialized sol-
vent  finishing.   Contribution  to  water pollution abatement  is modest
because scouring of knits does not contribute very  heavily  to  rextile
pollution loads.

Bleaching.  It is possible to bleach from solvent sytems and large scale
demonstrations  have  been  carried  out.   However,  the  process  used
generates both aqueous and solvent  wastes.   No  advantages  have  been
demonstrated with respect to fabric properties.

Dyeing.   A  very large effort has been devoted to solvent dyeing.   Some
fibers are commercially dyed from solvent systems, notably nylon sports-
wear and carpets by the STX beam dyeing  process.   The  advantages  and
limitations  of  solvent  dyeing,  both  practical and theoretical,  were
discussed at length  in  a  January  1973  AATCC  Symposium.   Collected
papers,  available from the American Association of Textile Chemists and
colorists Research Triangle  Park,  North  Carolina,  27709,  should  be
consulted  for  details.   Although many important textile' fibers can be
dyed from solvent systems, practical  applications  will  apparently  be
limited  to  special cases.  There are not grounds for broad reliance on
solvent processing to solve current  liquid  effluent  problems  arising
from dyeing operations.
Solvent	Finishing	Woven Goods.  It has been shown that many functional
finishes can be applied~from  solvents.   Some  advantageous  properties
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have  been  demonstrated, but no practical use has been achieved.   It is
believed that advantages shown so far have been insufficient to  justify
a  cnangeover from the familiar aqueous systems.  In any event, chemical
finishing is but a modest contributor to textile  effluents,  since  the
aim is to capture a very high fraction of the active agent on the  cloth.

In  special  cases, i.e., water-sensitive fabrics, solvent finishing has
become fairly standard practice.  Application of stain and  soil  resist
finishes to upholstery fabrics is a typical example.

solvent __ Finishing ___ of ____Knit __ Fabric.   Synthetic  knit  fabrics  lend
themselves  admirably  to  combination  scouring  and   finishing    from
solvents.   Some  modern  finishes such as silicone polymers for single-
knits, can be applied  only  from  solvent.   In  other  cases,  solvent
processing  recommends   itself  because  of ease and speed of drying, or
because of superior properties developed by solvent finishing.  Although
much of this development started with batch operations in  dry  cleaning
machinery,   high  developed  continuous  processing  machines  are  now
available from several manufacturers, both domestic and foreign.  It  is
clear  that  solvent  processing  of  knit  fabrics  is  established and
growing.

In summary, solvent processing is clearly  finding  a  place  in  modern
textile  processing.   There are, however, no grounds for supposing that
aqueous processing will  be totally displaced by solvent processing.
                                   Most woven goods require the  use  of
warp  size  during manufacture.  The sizing, traditionally starch, coats
the warp yarns and binds the individual fibers together.  This acrion is
necessary to preserve the warps from excessive  abrasion  damage  during
weaving.   The sizing is generally removed as the first operation in the
fabric finishing sequence.  Warp size constitutes, on the average, about
5 percent of the weight of the  fabric,  and  it  all  ends  up  in  the
effluent  waters.   Accordingly, it is a very substantial contributor to
the total BOD and COD in textile mill effluents.  Sizing waste  accounts
for about half the total BOD and COD load from textile operations.

Since  the  advent  of  synthetic  fibers, newer sizing agents have been
developed.  A solubilized cellulose derivative,  and  polyvinyl  alcohol
have  been  widely  used.   At  this  time, PVA, alone or in blends with
starch, is the most popular  size  for  the  important  cotton/polyester
blend fabrics.


Solvent  methods  offer  one  possible  route to allocation of the heavy
pollution load from warp sizes.  The concept  is  to  apply  a  solvent-
soluble  polymer,  then  remove  it by solvent washing following weaving
and, finally, to recover the polymer for re-use.  There is every  reason
to  suppose that suitable polymers can be found.  At least two companies
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are actively working in this  direction.    Early  indications  are  that
solvent- applied warp size can be effective.   The future potential of the
process depends upon successful recovery and re-use of the size.

Since  the size is to be used repeatedly, some means to purge impurities
is mandatory.  While this is a difficult problem, the  potential   advan-
tages  of  solvent size and desize are substantial.  Solvent size/desize
will eventually find practical application.   It is likely that  adoption
of  new  sizing technology will be based on demonstrated advantages over
conventional methods rather than  on  pollution  control  considerations
alone.

Specific I n^ Pr oce s s Changes
Wool Scourimj.  ORe °f "^fr6 problems in defining wool scour wastes and in
controlling  the  process  for  optimum performance is that detergent is
added on a fixed flow basis, and the demand for it  varies  widely  with
the  natural  variations  in  the fleece as received.  Future effort may
profitably be spent in developing a  method  to  measure  the  detergent
demand  and  control  its  addition  accordingly; less detergent will be
used, BOD load reduced and perhaps a more easily separated emulsion will
yield higher grease recoveries.

In addition, in the centrifuge recovery system described,   rewashing  of
the  grit for recovery of up to 40 percent more grease than is presently
being  recovered,   appears   possible   with   developmental   efforts.
Furthermore,  the  value  of  centrifuge-recovered wool grease is higher
than that of acid-cracked grease  (20£ per pound in 1973).


Re-use of the waste treatment plant effluent as  make-up  water  to  the
scouring  train  may  be  feasible.  One of the obvious problems is that
dissolved salts will build up.


solvent scouring has been used to remove the wool grease from the  wool.
Jet  fuel,  benzene, carbon tetrachloride, ethyl alcohol,  methyl alcohol
and isopropyl alcohol have been tried.  The problems of f laimmability and
explosive hazards, and of efficiency of solvent recovery have  prevented
its use in the United States.

Solvent  scouring  requires  subsequent  detergent washing to remove the
dirt.  More  efficient  methods  of  grease  recovery  using  the  water
scouring  process  appear  capable  of  achieving grease recovery levels
comparable to that with solvent methods, and hence would probably  offer
the better choice for further reducing pollution load in the future.

wool  Finishing.  Further effort should be extended to segregating waste
streams within the mill.  In particular, many of the rinse waters appear
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satisfactory for reuse both for subsequent initial rinses and  for  pre-
scouring steps and perhaps for fulling rinses.

Solvent  scouring  is  practiced  in  several  mills in place of initial
detergent scouring, to remove spin oils, sizes, and fugitive tints.  The
savings in detergent costs appear to justify these systems resulting  in
a lower BOD load and somewhat lower water use.


Woven  and	Knit  Fabric	Finishing  and _Stock	and	Yarn	Dyeing^  The
possibilities for reducing water consumption in finishing  woven  fabric
were  discussed  earlier.   In this section we will emphasize pollutants
other than water.

Scouring, mercerizing and bleaching generate substantial wastes,  parti-
cularly  in  textiles  containing  cotton.   Large textile users already
recover spent caustic soda and this should be extended to other users.

Better control and automation of  dyeing  processes  could  bring  about:
reductions in dye and chemical usage as well as in water.

There  is  no  simple  way  to reduce the amounts of auxiliary chemicals
essential for dyeing, e.g., salts, sodium hydrosulfite and a few others.
some mills are abandoning the use  of  chromates,  and  substitutes  are
generally  as effective.  The use of pressure becks for dyeing polyester
is increasing, and reducing carrier usage significantly.  Printing  pro-
cesses  frequently  use solvents  (Varsol)  which can be recovered by flo-
tation and distillation.


Carpets.   Continuous dyeing has been stated to use 20 to 25 percent  of
the  amount  of  water  used  in beck dyeing.  Stock dyeing and printing
rinse also are similar lower level uses.  However,  a  mill  can  use  a
continuous  process  only if the volume of a given shade is sufficiently
high.

If polyester regains as a major face-yarn material,  there  will  be  an
increase  in  raw  waste load.  This can be abated to some extent by the
use of pressure dye becks, as in subcategories 4 and 5,  that  permit  a
reduction in the use of carriers and their attendant heavy BOD load.

Biological Treatment Technology

The  treatment of waste effluents by biological methods is an attractive
alternative when a high proportion of the biodegradable material  is  in
the soluble form, as is the case in the textile industry.  These methods
are  applicable  in  this  industry  irrespective  of plant size, age or
location.
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Many types of microoganisms remove organic materials from liquid wastes.
Those most commonly used in Treatment systems  are  heterotrophs,  which
utilize  organic  carbon  for their energy and growth.   Some are aerobic
and require molecular oxygen for converting wastes to carbon dioxide and
water.   Others  are  anaerobic  and  grow  without  molecular   oxygen.
Anaerobic  microorganisms grow more slowly than aerobes and produce less
sludge per  unit  of  waste  treated  than  do  aerobic  microorganisms.
Anaerobes  also  release  acids and methane, and their action on sulfur-
containing wastes may create odor  problems.   Some  microorganisms  are
facultative;  that  is,  they can grow in either an aerobic or anaerobic
environment.

The biological treatment of  industrial  wastes  often  lacks  necessary
nutrients  in  the  waste to sustain desirable biological growth.  Added
nutrients, most often nitrogen and sometimes phosphorus, may be required
for efficient biological treatment  cf  processing  wastes.   Processing
wastes  generally  requires  the  addition of nitrogen before successful
biological treatment.  Often this can be  economically  accomplished  by
the  addition  of  nutrient-rich wastes from another source for combined
treatment.

A discussion of the various methods of biological treatment is presented
in the following sections.
                 ln this case  the  active  biota  is  maintained  as  a
suspension  in  the  waste  liquid.   Air,  supplied  to  the  system by
mechanical  means,  mixes  the  reaction   medium   and   supplies   the
microorganisms  with  the  oxygen  required  for  their metabolism.   The
microorganisms grow and feed on the nutrients  in  the  inflowing  waste
waters.  There are fundamental relationships between the growth of these
microorganisms and the efficiency of the system to remove BOD5.

A  number  of  activated sludge systems have been designed, all of which
have their own  individual  configurations.   Basically,  these  designs
consist of some type of pretreatment, usually primary sedimentation, and
aeration, followed by sedimentation which will allow the sludge produced
to  separate,  leaving a clear effluent.  Portions of the settled sludge
are recirculated and mixed with the influent to  the  aeration  section,
usually  at  a  proportion  ranging between 10 to 100 percent, depending
upon the specific modification ot the basic activated sludge process.

The goal of these plants is to produce an actively  oxidizing  microbial
population  which  will  also  produce  a dense "biofloc" with excellent
settling characteristics.  Usually,  optimization  of  floe  growth  and
overall  removal is necessary since very active microbial populations do
not always form the best floes.

Activated sludge treatment plants are capable of removing 95 percent  or
better of the influent BOD5 from textile manufacturing plants.
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The  extended  aeration  modification of the activated sludge process is
similar to the conventional activated sludge process,   except  that  tha
mixture  of  activated  sludge  and  raw  materials is maintained in the
aeration chamber for longer periods of time.  The common detention  time
in  extended  aeration  is  one  to  three  days, rather than six hours.
During this prolonged contact between the sludge and raw waste, there is
ample time for organic matter to be adsorbed by the sludge and also  for
the organisms to metabolize the removal of organic matter which has been
built  up  into  the  protoplasm of the organism.  Hence, in addition to
high organic removals from the waste waters, up to  75  percent  of  the
organic  matter of the microorganisms is decomposed into stable products
and consequently less sludge will have to be handled.

In extended aeration, as in the conventional activated  sludge  process,
it  is necessary to have a final sedimentation tank.  some of the solids
resulting from extended aeration are rather finely divided and therefore
settle slowly, requiring a longer period of settling.

The long detention time in the extended aeration tank makes it  possible
for nitrification to occur.  If it is desirable for this to occur, it is
necessary  to have sludge detention times in excess of three days.  This
can be accomplished by regulating the amounts  of  sludge  recycled  and
wasted  each  day.  Oxygen enriched gas could be used in place of air in
the aeration tanks to improve overall performance.  This  would  require
that  the  aeration  tank  be  partitioned and covered, and that the air
compressor and dispersion system  be  replaced  by  a  rotating  sparger
system,  which  costs  less to buy and operate.  When co-current, staged
flow and recirculation of gas  back  through  the  liquor  is  employed,
between 90 and 95 percent oxygen utilization is claimed.

Activated  sludge  in  its  varied forms is an attractive alternative in
textile waste treatment.  Conventional design criteria is  not  directly
transferrable  from  municipal  applications.   However,  high levels of
efficiency are possible at the  design  loadings  normally  employed  in
treating  other  types  of  high  strength  organic wastes.  The general
experience has been that biological solids separation  problems  can  be
avoided  if  the  dissolved  oxygen  concentration  remains  above  zero
throughout the aeration basin,  if  management  minimizes  very  strong,
concentrated  waste  releases, and if sufficient amounts of nitrogen are
available to maintain a critical nitrogen:  BOD5 ratio.  This ratio  has
been  recommended  to be 3 to 4 kg(Ib) N per 100 kg(Ib) of BOD5 removed.
Numerous cases have been reported of successful  combined  treatment  of
textile  and  domestic wastes by activated sludge and its modifications.
Activated sludge systems require less room  than  other  high  reduction
biological  systems,  but  have  higher  equipment  and operating costs.
Properly designed and operated  systems  can  treat  textile  wastes  to
achieve high BOD reductions.
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    °2i£iLi	FjItgation _fTrickling gilter):  The trickling filter process
has found application in treatment of many industrial wastes.  Very tall
filters employing synthetic media, high recirculation,  and  forced  air
circulation  have  been used to treat strong wastes in the 300-4000 mg/1
BOD5 range.

The purpose of the biofilter system is to change soluble organic  wastes
into  insoluble  organic  matter  primarily  in the form of bacteria and
other higher  organisms.   As  the  filter  operates,  portions  of  the
biological growth slough off and are discharged as humus with the filter
effluent.  Usually, some physical removal system is required to separate
this  insoluble  organic material which can be treated by other suitable
methods, usually anaerobic fermentation in a sludge digester.

Trickling filters are usually constructed as circular  beds  of  varying
depths  containing  crushed  stone,  slag,  or  similar  hard  insoluble
materials.  Liquid wastes are distributed over this bed  cit  a  constant
rate  and allowed to "trickle" over the filter stones.  Heavy biological
growths develop on the surface of  the  filter  "media"  throughout  the
depth of the filter and also within the interstitial spaces.

The  biological  film  contains  bacteria,  (Zooglea,  Sphaerotilus, and
Beggiatoa); fungi  (Fusarium, Geotrichum, sepedonium); algae, both  green
and  blue-green   (Phormidium,  Ulothrix,  Mononostrona); and a very rich
fauna of protozoa.  A grazing  fauna  is  also  present  on  these  beds
consisting  of  both  larval  and  adult  forms  of worms  (Oligochaeta),
insects  (Diptera and Coleoptera among others),  and  spiders  and  mites
 (Arachnida) .

A common problem with this type of filter is the presence of flies which
can  become  a  severe  nuisance.   Insect  prevention  can  usually  be
prevented by chlorinating the influent cr by periodically  flooding  the
filter.


Recirculation  of  waste  water flows through biological treatment units
are often used to distribute the load of impurities  imposed on the  unit
and  smooth  out  the applied flow rates.  Trickling filtejr BOD5 removal
efficiency is  affected  by  temperature  and  the   recirculation  rate.
Trickling  filters  perform  better  in  warmer  weather  than in colder
weather.  Recirculation of effluent increases BOD5 removal efficiency as
well as keeping reaction type rotary  distributers   moving,  the  filter
media moist, organic loadings relatively constant, and increases contact
time with the biologic mass growing on the filter media.

Furthermore,  recirculation  improves distribution,  equalizes unloading,
obstructs entry and  egress  of  filter  flies,  freshens  incoming  and
applied  waste  waters, reduces the chilling of filters, and reduces the
variation in time of passage through the secondary settling tank.
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Trickling filter BOD5 removal efficiency is  inversely  proportional  to
the  BOD5  surface loading rate; that is, the lower the BOD5_ applied per
surface area, the higher the  removal  efficient.   Approximately  10-90
percent BOD reduction can be attained with trickling filters.

Anaerobic	Processes: Elevated temperatures  (29° to 35°C or 85° to 95°F)
and the high concentrations typically found in  industrial  wastes  make
these   wastes   well  suited  to  anaerobic  treatment.   Anaerobic  or
faculative microorganisms, which function in the  absence  of  dissolved
oxygen,  break  down the organic wastes to intermediates such as organic
acids and alcohols.  Methane bacteria  then  convert  the  intermediates
primarily  to carbon dioxide and methane.  Also, if sulfur compounds are
present hydrogen sulfide may  be  generated.   Anaerobic  processes  are
economical  because  they  provide  high  overall  removal  of  BOD5 and
suspended solids with no power cost  (other than pumping)  and  with  low
land  requirements.   Two  types  of  anaerobic  processes are possible:
anaerobic lagoons and anaerobic contact systems.

Anaerobic lagoons are used as the first step in secondary  treatment  or
as pretreatment prior to discharge to a municipal system.  Reductions of
85  percent  in  BOD5 and 85 percent in suspended solids can be achieved
with these lagoons.   A  usual  arrangement  is  two  anaerobic  lagoons
relatively  deep   (3  to 5 meters, or about  10 to 17 feet), low surface-
area systems with typical waste loadings of  240  to  320  kg  BOD5/1000
cubic  meters (15 to 20 Ib BOD5/1000 cubic feet) and a detention time of
several days.

Plastic covers of  nylon-reinforced  Hypalon,  polyvinyl  chloride,  and
styrofoam  can  be  used  on  occasion  to  retard  heat loss, to ensure
anaerobic conditions, and hopefully to retain obnoxious odors.  Properly
installed covers provide a convenient method for collection  of  methane
gas.

Influent  waste water flow should be near, but not on, the bottom of the
lagoon.  In some installations, sludge is recycled  to  ensure  adequate
anaerobic seed for the influent.  The effluent from the lagoon should be
located  to prevent short-circuiting the flow and carry-over of the scum
layer.


Advantages of an anaerobic lagoon system are initial low cost,  ease  of
operation, and the ability to handle shock waste loads, and yet continue
to provide a consistent quality effluent.  Disadvantages of an anaerobic
lagoon  are  odors  although  odors are not usually a serious problem at
well managed lagoons.

Anaerobic lagoons used as the first stage  in  secondary  treatment  are
usually  followed  by  aerobic  lagoons.   Placing a small, mechanically
aerated lagoon between the anaerobic and  aerobic  lagoons  is  becoming
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popular.   It  is  currently  popular to install extended aeration units
following the anaerobic lagoons to obtain nitrification.

The anaerobic contact system requires far more equipment   for  operation
than  do  anaerobic  lagoons,  and consequently is not as commonly used.
The equipment, consists of equalization  tanks,  digesters  with  mixing
equipment,  air  or  vacuum gas stripping units, and sedimentation tanks
(clarifiers).  Overall  reduction  of  90  to  97  percent  in  BOD  and
suspended solids is achievable.

Equalized  waste  water  flow  is introduced into a mixed digester where
anaerobic decomposition takes place at a temperature  of   about  33°  to
35°C (90° to 95°F).  BOD5 loadings into the digester are  between 2.4 and
3.2 kg/cubic meter (0.15 and 0.20 Ib/cubic foot), and the detention time
is  between  three  and twelve hours.  After gas stripping,  the digester
effluent is clarified and sludge is recycled at a  rate  of   about  one-
third  the  raw  waste  influent  rate.   Sludge  at the  rate of about 2
percent of the raw waste volume is removed from the system.

Advantages of the anaerobic contact system are high organic   waste  load
reduction  in  a  relatively  short  time;  production and collection of
methane gas that can be used to  maintain  a  high  temperature  in  the
digester  and  also  to  provide  auxilary heat and power; good effluent
stability to waste load shocks; and application in areas  where anaerobic
lagoons  cannot  be  used  because   of   odor   or   soil   conditions.
Disadvantages  of anaerobic contractors are high initial  and maintenance
costs and some odors omitted from the clarifiers.

Anaerobic contact systems  are  usually  used  as  the  first  stage  of
secondary  treatment and can be followed by the same systems that follow
anaerobic lagoons or trickling filter roughing systems.

Other^Aerobic^Procegses^ Aerated lagoons have been used successfully for
many years in a number of installations for treating industrial  wastes.
However,  with  recent tightening of effluent limitations and because of
the additional treatment aerated lagoons  can  provide,  the  number  of
installations is increasing.

Aerated  lagoons  use  either  fixed  mechanical  turbine-type aerators,
floating propeller-type aerators, or a diffused air system for supplying
oxygen to the waste water.  The lagoons usually are 2.4 to 4.6 m  (8  to
15  feet)  deep,  and  have  a  detention time of two to  ten days.  BOD5
reductions range from 40 to 60 percent with little or  no  reduction  in
suspended  solids.  Because of this, aerated lagoons approach conditions
similar to extended aeration without sludge recycle.


Advantages of this system are that it can rapidly add  dissolved  oxygen
(DO)  to  convert  anaerobic  waste  waters to an aerobic state; provide
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additional BOD5 reduction;  and require  a  relatively  small  amount  of
land.   Disadvantages  are  the  power requirements and that the aerated
lagoon, in itself, usually does not reduce  BOD5  and  suspended  solids
adequately to be used as the final stage in a high performance secondary
system.   Aerated  lagoons  are  usually  a  single  stage  of secondary
treatment and should be followed  by  an  aerobic  (shallow)   lagoon  to
capture suspended solids and to provide additional treatment.

Aerobic lagoons (or stabilization lagoons or oxidation ponds), are large
surface  area,  shallow  lagoons, usually 1 to 2.3 m deep (3 to 8 feet),
loaded at a BOD5 rate of 22-56 kilograms per hectare (20  to  50  pounds
per  acre).  Detention times will vary from several days to six or seven
months; thus aerobic lagoons require large areas of land.

Aerobic lagoons serve three main functions in waste reduction:

1.  Allow solids to settle out.

2.  Equalize and control flow.

3.  Permit stabilization of organic matter by aerobic and facultative
    microorganisms and also by algae.

Actually, if the pond is quite deep, 1.8 to 2.4 m (6 to 8 feet), so that
the waste water near the bottom is void of dissolved  oxygen,   anaerobic
organisms  may  be present.  Therefore, settled solids can be decomposed
into  inert  and  soluble  organic  matter  by  aerobic,  anaerobic   or
facultative  organisms,  depending  upon  the  lagoon  conditions.   The
soluble organic matter is also decomposed by microorganisms causing  the
most  complete  oxidation.    Wind  action  assists in carrying the upper
layer of liquid (aerated by air-water interface and photosynthesis)  down
into  the  deeper  portions.   The  anaerobic  decomposition   generally
occurring  in  the  bottom  converts solids to liquid organics which can
become nutrients for the aerobic organisms in the upper zone.

Algae growth is common in aerobic lagoons; this currently is a  drawback
when  aerobic  lagoons  are  used for final treatment.  Algae may escape
into the receiving waters,  and  algae  added  to  receiving  waters  are
considered a pollutant.  Algae in the lagoon, however, play an important
role  in  stabilization.   They use CO2, sulfates, nitrates, phosphates,
water and sunlight to synthesize their own organic cellular  matter  and
give   off   free  oxygen.    The  oxygen  may  then  be  used  by  other
microorganisms for their metabolic processes.  However, when  algae  die
they  release  their  organic  matter in the lagoon, causing a secondary
loading.  Ammonia disappears without the  appearance  of  an  equivalent
amount  of  nitrite  and nitrate in aerobic lagoons.  From this, and the
fact that aerobic lagoons tend to become anaerobic near the  bottom,  it
appears that some denitrification is occurring.
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High  winds  can  develop  a  strong  wave action that can damage dikes;
Riprap, segmented lagcons, and finger dikes are  used  to  prevent  wave
damage.   Finger  dikes, when arranged appropriately, also prevent short
circuiting of the waste water  through  the  lagoon.    Rodent  and  weed
control,  and  dike  maintenance are all essential for good operation of
the lagoons.

Advantages of aerobic lagoons are that  they  reduce  suspended  solids,
oxidize  organic  matter,  permit  flow control and waste water storage.
Disadvantages are the large land required, the algae growth problem, and
odor problems.

Aerobic lagoons usually are the last stage in  secondary  treatment  and
frequently  follow  anaerobic or aerated lagoons.  Large cierobic lagoons
allow plants to store waste water discharges during periods of high flow
in the receiving body of water or to store . for  irrigation  during  the
summer.   These  lagocns  are  particularly popular in rural areas where
land is available and relatively inexpensive.

Rotatin3_Biolx>gi£al_Contcictor:The rotating  biological  contactor   (RBC)
consists  of  a  series  of closely spaced flat parallel disks which are
rotated while partially immersed in the waste waters being  treated.   A
biological  growth  covering  the  surface of the disk adsorbs dissolved
organic matter present in the waste water.  As the biomass on  the  disk
builds  up,  excess slime is sloughed off periodically and is removed in
sedimentation tanks.  The rotation of the disk carries a  thin  film  of
waste  water  into the air where it absorbs the oxygen necessary for the
aerobic biological activity of the  biomass.   The  disk  rotation  also
promotes  thorough  mixing and contact between the biomass and the waste
waters.  In many ways the RBC system is a compact version of a trickling
filter.  In the trickling filter the waste waters flow  over  the  media
and  thus  over  the  microbial  flora;  in the RBC system, the flora is
passed through the waste water.

The system can be staged  to  enhance  overall  waste  water  reduction.
Organisms  on  the  disks selectively develop in each stage and are thus
particularly adapted to the composition of the waste in that stage.  The
first couple of stages might be used for removal  of  dissolved  organic
matter,  while the latter stages might be adapted to other constituents,
such as nutrient removal.

The major advantages of the RBC system are its relatively low  installed
cost,   the  effect  of   staging  to  obtain  dissolved  organic  matter
reductions,  and  its  good  resistance  to   hydraulic   shock   loads.
Disadvantages  are  that  the  system  should be housed to maintain high
removal efficiencies and  to control odors.   Although  this  system  has
demonstrated  its  durability  and  reliability  when  used  on domestic
wastes, it has not yet been fully tested  to  treat  textile  processing
wastes.
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Rotating  biological  contactors  could  be  used for the entire aerobic
secondary system.  The number of stages required depend on  the  desired
degree  of treatment and the influent strength.  Typical applications of
the rotating biological contactor, however, may  be  for  polishing  the
effluent  from  anaerobic  processes and from roughing trickling filters
and as pretreatment pricr to discharging wastes to a  municipal  system.
A  BODS  reduction  of  over 90 percent is achievable with a multi-stage
RBC.
£§£f o^E^nce of Biological Treatment Systems

Evaluation of data obtained  from  the  textile  waste  water  treatment
plants  surveyed  indicate  that  the  operational  mode  for  exemplary
biological systems is extended aeration.   No  exemplary  plant  has  an
average  residence  time  in  the  aeration basin of less than 17 hours.
Eighteen exemplary  biological  systems  with  an  average  BOD  removal
efficiency  of  greater  than  95  percent  are listed in Table 27.   The
complete treatment scheme for  most  exemplary  waste  treatment  plants
includes  screening  and extended aeration followed by clarification and
polishing lagoons.

Removal of fibers from the waste  water  prior  to  their  entering  the
aeration basin is often necessary to prevent floating scum from building
on  the  surface  of the basin or to prevent the aeration equipment from
malfunctioning and reducing oxidation efficiency.  Usually, these fibers
are removed satisfactorily through the use of bars or screens.

Removal of BODS  and  suspended  solids  from  textile  waste  water  is
accomplished  most  satisfactorily  through  the  employment of extended
aeration including clarification and sludge return.  Textile waste water
usually contains ample phosphates which are available as  nutrients  for
the  microorganism  of  the  biological system.  Nitrogen in the form of
ammonia or nitrate may be required in some cases in which this  nutrient
deficiency has been identified.

Suspended  solids  are  removed from biologically-treated waste water by
gravity  sedimentation.   The  concentrated  slurries  are  recycled  to
aeration  basins  while  the overflow from the clarifier goes to lagoons
for further polishing or discharge to the receiving stream.  Because  of
colloidal particulates from certain operations, chemical coagulation may
be  required  prior  to biological treatment.  This operation is usually
carried out by the addition of coagulating chemicals and/ or the  use  of
coagulant  aids  to  improve  sedimentation.  In general, the clarifiers
used  in  the  textile  industry  are  designed   for   overflow   rates
considerably less than those usually found in municipal systems.

Excluding  the  high  BODS  values  for wool scouring-subcategory 1, the
average BODS concentration of the exemplary treatment is about 20  mg/1,
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running  from  a  low  of  2  'to  a  high  of  83  mg/1.    Of this group
approximately 20 percent exceeded  30 mg/1.

In effect, many of the waste water treatment plants are  being  operated
as  a  two-stage  biological  system  since polishing lagoons of various
residence times may follow the aerated basin.


Chemical oxygen demand (COD)  is measured less frequently than BODS.    As
in the case of BODS, the COD of wool scouring waste is greater than that
of  waste  waters  from other categories, both on a concentration basis.
Exclusive of the wool scouring waste, the industry's average COD for the
plants surveyed is 222 mg/1 with a low value of 68 mg/1 and  a  high  of
427  mg/1.   The ratio of COD to BODS increases significantly across the
waste water treatment plants, which indicates the refractory  nature  of
some  of the components of the waste waters.  Although COD is probably a
better measure of the pollutant level of waste waters, other  parameters
such as total organic carbon  (TOG)  or total oxygen demand  (TOD)  might be
even more indicative.

Although the ratio of CCD to BOD is generally recognized as an indicator
of  the  biologically  refractory  nature of waste water pollutants, the
variability in this ratio is affected  by  many  factors.   One  is  the
capabilities  of  a  specific  biological system to degrade carbonaceous
substances.  For example, PVA, one of the  biggest  sizes  used  in  the
textile  industry,  has  been considered to be essentially refractory in
terms of its loading on  an  activated  sludge  plant,  1  percent  BOD,
whereas  the  theoretical  oxygen  demand  is  36  percent.   This would
indicate that only 3 percent of the PVA is normally attacked in a  five-
day  BOD  test,  or  loosely  speaking,  97  percent  of  it  would pass
unaffected through an activated  sludge  plant.   However,  recent  data
shows  that  this is not the case;  in some activated sludge plants where
the organisms  have  become  acclimated  to  the  PVA,  substantial  PVA
reduction is achieved.


Textile   process   operations  often  require  high-temperature  water,
however, heat reclamation is  also  widely  practiced  as  a  matter  of
economics  so  the  waste waters sent to the treatment plcints usually do
not present any significant thermal shock  problems.   Furthermore,  the
long residence time generally found in the waste water treatment systems
serves  effectively  to  prevent rapid changes in temperature.  The most
important temperature effect is not expected to  be  high  temperatures,
but   low   temperatures.    In   northern  areas,  the  low  wintertime
temperatures in biological treatment systems will  reduce the biological
activity and thus the efficiency of BODS removal.

Color in the waste waters of the textile industry  is  inherent  in  the
nature  of  the  operations.   Since  color  chemicals  are specifically
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formulated for resistance to degradation under the oxidizing  conditions
of  the  world,  it  is  not surprising that removal of color in aerobic
biological systems is erratic.  Although color concentration normally is
reduced somewhat in the biological systems surveyed, data obtained  were
in   arbitrary  units,  most  often  APHA(Y)   standard.    Color  removal
efficiency is known to be highly specific to the  individual  plant  and
the  particular  processes  being  operated at a given time.  Although a
number of research and development projects have been carried out, there
is  no  one  generally  accepted  method  for  color  removal.   Use  of
adsorptive  technology—such  as flocculation and activated carbons—and
anaerobic treatment appear to offer the best  possibility  for  removing
color.

Chromium  is  the most significant heavy metal of concern in the textile
industry although  others  are  employed  selectively.   There  is  good
evidence  that  at  low levels of chromium in the raw waste an activated
sludge treatment plant removes a substantial portion.

Pollution experts within the textile industry  have  noted  that  chrome
removal  across a waste treatment plant is proportional to the amount of
BOD removed   (more  specifically  the  excess  sludge  removed)   and  is
inversely proportional to the amount of suspended solids carried over in
the  final  effluent  from  the  secondary clarifier.  Proper removal of
chrome is dependent on proper removal of suspended solids.


Other	constituents;  Wastewaters  from  ancillary  operations  such  as
cooling  towers,  steam generating facilities and water treatment plants
may be significant factors in the waste water volumes emitted  from  the
textile  industry.   In  those  instances  where one must handle cooling
tower and boiler blowdowns that contain corrosion inhibiting  chemicals,
algacides  and biocides, the technology for selective removal is usually
available.  Of course, the best practicable control technology currently
available for process waste waters will  not  remove  soluble  inorganic
salts  which  predominate  in  these  blcwdowns.   Toxic  and  hazardous
substances in these systems can  be  controlled  either  by  eliminating
them,  replacing  them  with  less  toxic  and  hazardous  substances or
treating isolated streams to remove them.   Selection  of  a  course  of
action  to cope with toxic and hazardous materials in these blowdowns is
more a question of economics than a question of technology.

Reliability, operability and consistency of operation of the waste water
treatment processes found to be most  frequently  used  in  the  textile
industry  can  be high if appropriate designs and operational techniques
are employed.  The end-of-pipe  treatment  utilizing  extended  aeration
biological  systems  is  a  well  established  technology  that requires
attention to a limited number of variables to insure a  high  degree  of
reliability.   Although  many  variables can affect the operability of a
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biological system,  in general the best overall performance  is  achieved
when the highest consistency of flow and waste water composition occurs.

Since  the  textile  industry  is  predominantly  a  batch  type process
operation rather than continuous, it follows that both  flow  rates  and
waste  water  composition  will  vary  significantly.  That the industry
recognizes this variability is apparent from the  nature  of  the  waste
water  treatment  systems,  i.e., long residence time systems which hold
sufficient volumes  so  that  high  instantaneous  flow  rates  or  high
concentrations  can be rapidly equalized to prevent shock loading of the
biological system.

The most  important  operational  aspects  of  these  extended  aeration
systems  are equipment reliability and attention to operating detail and
maintenance.   Spare  aeration  equipment  (usually   floating   surface
aerators)  improves  the  possibility  of consistent operation; however,
many treatment systems have an adequate overcapacity  already  installed
as insurance against the results of equipment failure.  It is  desirable
to  install  spare  equipment  at  critical  points, for example, sludge
return pumps.  Perhaps cf equal importance  is  a  design  that  permits
rapid and easy maintenance of malfunctioning equipment.

Therefore, control of the biological treatment plant and the consistency
of  the results obtained are largely a matter of conscientious adherence
to well-known operational and maintenance procedures.  Automatic control
of biological treatment plants is far from a practical point.   Although
in-line   instrumentation  for  measurement  of  pH,  dissolved  oxygen,
temperature, turbidity and so  on,  can  improve  the  effectiveness  of
operation,  its  use is minimal in the textile industry's existing waste
water   treatment   plants.    Nevertheless,   no   practical    in-line
instrumentation  can  replace  the  judicious  attention  to operational
details of a conscientious crew of operators.

An activated sludge system which is permitted to operate at  a  constant
F:M ratio all year round and with minimum operational changes would have
a  natural  variation as shown in section IX by the solid line in Figure
19.  A similar system with careful  operational  control  would  have  a
controlled  monthly  average variation as shown by the points.  Although
the mean  value  is  the  same,  the  amount  of  natural  variation  is
controlled  by  the  operator  through  aeration  rate  control,  sludge
recycling and F:M ratio adjustments.   These  adjustments  can  be  made
daily so that monthly averages can be held within the desired  limits.

Although   a   well-operated  and  properly  designed  facility  can  be
controlled within +25 percent of the  average  on  a  monthly  operating
basis.  A system with minimal operational control or an allowance of +50
percent  of  the  averages on a monthly basis has been used to calculate
the maximum monthly effluent limitation.
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ADVANCED WASTE WATER TREATMENT TECHNOLOGY


In all categories of textile plants, it is assumed that  good  secondary
treatment  will  have  a  high  quality  effluent as demonstrated by the
exemplary plants.  The  definition  of  advanced  treatment  systems  is
therefore  confined  to  tertiary  treatment of the secondary effluents,
dewatering and incineration of sludges, and possibly to  preconditioning
of  some  specialized  waste  streams to render them compatible with the
advanced waste treatment process.

In some cases, advanced treatment systems have been tried out on textile
wastes and their effectiveness in dealing with these  various  pollutant
parameters has been assessed.  In other cases it is necessary to predict
their  usefulness  to  the  textile  industry from experience with other
similar waste streams or by an  understanding  of  the  physico-chemical
principles involved.


The  processes  under  consideration  have been grouped according to the
overall chemical or physical mechanism of their operation:

         1.  phase change
         2.  physical separation
         3.  sorpt ion
         4.  chemical clarification

                              Phase_Chanqe

Distillation; The multistage flash MSF process consists  essentially  of
pumping  hot  salt,  brackish,  or  contaminated  water through suitable
nozzles into a chamber in which the temperature and pressure  are  lower
than  that of the water itself.  Part of the water flashes off instantly
as steam which passes through demisters to remove entrained droplets  of
impurities  and  condenses on tubing cooled by entering feed water.  The
distilled water drops off the tubes into a trough and  is  collected  as
the product water.

In  order  to  improve the efficiency of the process and recover most of
the heat energy a multi-stage system is preferred in  which  the  latent
heat  from  the  condensation  of  the steam produced in the evaporation
chamber is used to preheat the cooler feed water flowing in the  conden-
ser tubes counter current to the brine in the flash chambers.  Thus, the
chief  thermal energy requirement is that needed to raise the feed water
from ambient temperatures to the  temperature  of  the  outgoing  brine.
Recirculation  of the brine improves thermal efficiency considerably and
all modern MSF plants are of this design.
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Two types of feed water treatment are generally employed to reduce scale
formation,  Frequently a proprietary  material  is  used,  containing  a
polyphosphate  or  polyelectrolyte as the active ingredient.  These com-
pounds do not prevent scale from forming but rather modify its character
so that it may be easily washed out or dissolved by weak acids  periodi-
cally.   Often acid treatment is used, with sulfuric acid generally pre-
ferred.  The acid is added continuously to the feed water  in  small  a-
mounts  to  reduce  the pH below 7 and decompose the carbonate compounds
that cause hard scaling in the tubes and flash chambers.  In many of the
units using acid, the carbon dioxide released by the acid, is removed  in
a  separate  decarbonatcr  placed  in  the  feed water circuit after the
reject stages.  Otherwise the carbon dioxide is removed with  the  other
dissolved  gases  by the steam jet deaerator.  In modern units steam jet
deaerators are used to deaerate the flash  chambers  and  to  produce  a
vacuum.

The  vertical tube evaporator (VTE) is a long-tube vertical distillation
type of desalting plant, (146.3 mgd) .

In the climbing-film vertical evaporator, the most  common  design,  the
brine  is maintained at a predetermined level inside the vertical tubes.
These tubes are heated externally by the incoming  steam  in  the  first
effect  or  by the hot product vapors in subsequent effects.  This is in
direct contrast to a submerged tube type of unit  which  has  the  steam
inside  and  the  boiling  brine outside the tubes.  The vapors from the
boiling brine rise in the vertical tubes into a vapor  chamber  and  are
led  from there into the vertical tube heat exchanger in the next effect
where the heat is given up to the brine circulating in these tubes.

The resulting fresh water condensed on the outside of the tubes  is  re-
moved  and  combined with product from the subsequent effects.  The com-
bined product is cooled in a final condenser with feed water.   The  in-
coming  feed  water  is  fed  into the first effect and the concentrated
brine flows in the same direction as the  vapors.   The  brine  in  each
effect circulates either by natural temperature differences or by forced
circulation.

In  another modification, known as the thermal recompression evaporator,
part of the vapors from the last effect are entrained and compressed  by
expanded  live steam from the boiler.  The resulting mixture becomes the
heating medium for  the  first  effect.   This  scheme  is  particularly
advantageous  where high-pressure steam is available as a source of heat
and it can be used in conjunction  with  a  single  or  multiple  effect
vertical-tube evaporator.

Relevance  to  Textile Waste Treatment.The waste waters from the textile
industry may have a moderately high concentration of  organic  chemicals
in comparison with the concentrations in brackish or saline waters.
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In  some  instances,  it  might  be  necessary  to  treat waste water by
activated carbon  adsorption  to  insure  adequate  removal  of  organic
species.   Therefore,  a  thorough  consideration  of the entire process
chemistry will be required before one can determine whether  evaporation
can  be  successfully  applied  to  waste waters containing carbonaceous
substances.  If the waste water streams contain very low  concentrations
of  organics  and  high concentrations of dissolved inorganic salts,  the
applicability  of  evaporation  is   more   readily   predicted,   being
essentially an evaluation of economics.

Freezing Techniques :

It  has  long  been  recognized  that  individual ice crystals formed in
chilled impure water are  composed  of  pure  water.   Much  effort  has
therefore  gone  toward  the  development of practical processes to take
advantage of this phenomenon for the  desalination  or  purification  of
water.  Attention is presently centered on two types of equipment.

The  vacuum  freeze vapcr compression  (VFVC)  system has the longest his-
tory.  In this type of device, feed water is chilled and  exposed  to  a
slight  vacuum.   Some  of the water vaporizes and the resulting loss of
heat of vaporization causes ice crystals tc form in the system.

The ice crystals are separated mechanically from the brine by  means  of
sieves  and  scrapers  and transferred to melting chambers.  At the same
time the water vapor formed during the boiling-freezing  stage  is   com-
pressed  and  introduced also to the melting chamber, where it condenses
on the ice crystals.  In practice the system is more  complicated,   with
particular  care  being required to wash the ice crystals free from feed
water and to maintain the correct temperatures and pressures throughout.

The second type of design employs as the vaporizing constituent a secon-
dary refrigerant which is insoluble in water.   Usually,  liquid  butane
under  pressure is bubbled through the feed water, vaporizing, expanding
and causing ice crystals to form.  As in the vacuum freeze  system,  the
crystals  are  then  separated mechanically and washed by liquid butane.
The secondary refrigerant system has the advantage  that  the  equipment
operates  at  higher  pressures and smaller volumes of gas (butane) , re-
sulting in less expensive and more reliable pumps and compressors.
          £o Textile Waste Treatment.  A few small VFVC plants have been
erected in this country and abroad for  desalination  of  seawater,  but
have not had enough service to develop useful histories.

Their  principal  advantage  appears  to  be  that  they  are relatively
insensitive to the nature of  the  chemicals  in  the  feed  water  and,
because  they  operate  at  low  temperatures,  resist  the  scaling and
corrosion problems which plague most other types of  plants.   None  has
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been  used  for waste water treatment.   The secondary refrigerant system
is still in the pilot plant stage of development.

Although neither type of freezing plant has been  used  in  the  textile
industry  for waste water treatment.  it might be attractive  because of
its tolerance of high levels of salts,  organics,  suspended  solids  and
other  materials  in  the  feed  water.  It can be operated at brine-to-
product ratios as low as about 0.02, and brine concentrations as high as
60,000 mg/1 TDS.  This, of course,  considerably  reduces  the  cost  of
ultimate brine evaporation or disposal.

                          Physical Separation

Filtration:

The  removal  of  suspended  solids  or colloidal material from water by
filtration is accomplished by one of a number of mechanisms which may be
generally classified as straining or transport attachment.  Straining is
the elimination of particulate matter by size discrimination; that is, a
particle of greater diameter than a  pore  opening  will  be  physically
restrained from passage.

Transport  - Attachment refers to a two step principle and is applied to
particulate matter which may be much smaller than the  pore  size.   The
particles  are  transported  across the stream lines to the proximity of
the filter medium where attachment forces predominate.

Filtration is the most common form of  advanced  waste  water  treatment
practiced  today.   This is due to its relatively inexpensive nature and
its  effectiveness  in  removing  suspended  solids  and  the   organics
associated  with  those  solids.   It  provides excellent preparation of
waste for application of other advanced waste treatment  techniques  and
is an integral part in many designs of these systems.

Relevance	to Textile Waste Treatment.  Rapid sand type filters have had
considerable use in waste treatment systems  for  direct  filtration  of
secondary effluent.

Early  work  on  filtration  of secondary effluent took place in Europe.
Truesdale and Birkbeck reported on tests run between October, 1949,  and
May   1950, at the Luton Sewage works.  Beds of  sand  2 feet deep, ranging
in size from 0.9 mm to  1.7 mm, exhibited 72 to  91   percent  removal  of
suspended solids and 52 to 70 percent  removal of BOD.  Flow rates ranged
from  1.33 to 3.3 IMP.gal/min/ft2.

Naylor,  Evans  and  Dunscome  later   reviewed  15   years  of studies of
tertiary treatment at Luton.  A 3-foot deep bed of 10 to   18  mesh  sand
consistently  provided  an  effluent   of 4 to  6 mg/1 suspended solids at
flow  rates of 3.3 Imp.gal/min/ft2.

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In the U. S., most direct filtration work has been with activated sludge
effluent.  At the Hyperion  Plant  in  Los  Angeles,  sand  of  0.95  mm
effective  size  was  used  in  a shallow bed (11 inches deep) traveling
backwash filter.  This study lasted for six months during which time  U6
percent  suspended  solids  removal  and  57  percent  BOD  removal were
obtained.   Filtration  rate  was   2   gal/min/ft2.    Difficulty   was
encountered   in   cleaning   the   filters  and  performance  gradually
deteriorated during the study.  Use of a finer sand (0.45  mm  effective
size) in an attempt to yield a better effluent was a failure due to very
rapid clogging of the filter.

Much  greater  success  utilizing  the  traveling  backwash  filter  for
activated sludge effluent treatment was obtained by  Lynam  in  Chicago.
The  effective  size  of sand used in this study was 0.58 mm.  Suspended
solids removal of 70 percent and BOD removal of 80 percent were obtained
at flow rates of 2 to 6 gal/min/ft2.  Terminal headloss  was  quite  low
(11  inches  of  water.)    The  range  of  flows  studied  exhibited  no
significant difference in terms of suspended solids removal.

Gulp and Gulp  reviewed  the  work  on  plain  filtration  of  secondary
effluent with both single medium and multimedia filters.  They concluded
that,  with  either  type of filter, better results would be obtained as
the degree of self flocculation of the sludge increased.  Thus, a  high-
rate  activated  sludge  effluent which contains much colloidal material
should filter poorly, while an extended aeration effluent should  filter
well.   Multi-media  filters exhibit a marked superiority for filtration
of activated sludge effluent because of the high volume of floe  storage
available  in the upper bed and the polishing effect of the small media.
They indicated the expected performance of multi-media filters for plain
filtration of secondary effluents as shown in Table 10.

                                Table 10

          EXPECTED EFFLUENT SUSPENDED SOLIDS FROM MULTI-MEDIA
                   FILTRATION OF BIOLOGICAL EFFLUENTS

              Biological System               Effluent TSS
                                                  (mg/1)

             High Rate Trickling                10-20

             2 - Stage Trickling Filter          6-15

             Contact Stabilization               6-15

             Conventional Activated Sludge       3-10

             Extended Aeration                   1-5
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The application  of  filtration  to  biologically  treated  effluent  is
dependent  on  the  nature  of  the biological system and the biological
solids produced by that system rather than the nature or characteristics
of the raw waste.  That  is,  application  of  filtration  to  secondary
effluent  from textile wastes will remove the biological solids the same
as it would remove the biological solids generated from other wastes.
       . Osmosis ._  Reverse osmosis for desalinization of  sea  water  and
brackish   water  has  been  under  extensive  investigation  since  the
discovery in the early 1960' s of high  flux  membranes  capable  of  re-
jecting  salts.   Much  of  the research and development work was made ,
with a view toward recovering potable water from  sea  water.   Although
this  aim  still  has not been fully attained at prices competitive with
other processes such as flash distillation, improved technology  arising
from  these  programs  and increased commercial interest has resulted in
some successful utilization of reverse osmosis for removal of  dissolved
salts from industrial waste streams.

The  process  of  reverse  osmosis   relies  upon the ability of certain
specialized polymeric membranes, usually cellulose acetate or  nylon  to
pass  pure  water  at  fairly high rates and to reject salts.  And to do
this saline feed streams are passed at high pressures over the  surfaces
of  the  membranes.  The applied hydraulic pressures must be high enough
to overcome the osmotic pressure of  the  saline  feed  stream,  and  to
provide  a  pressure  driving  force  for  water to flow from the saline
compartment through the membrane into the fresh water compartment.

In a typical reverse osmosis system.   Feedwater  is  pumped  through  a
pretreatment  section which removes suspended solids  and, if necessary,
ions such as  iron  and  magnesium  which  may  foul  the  system.   The
feedwater  is  then pressurized and sent through the reverse osmosis mo-
dules.  Fresh water permeates through the membrane  under  the  pressure
driving  force,  emerging  at atmospheric pressure.  The pressure of the
concentrated brine discharge stream is reduced by a power recovery  tur-
bine, which helps drive the high pressure pump, and then is discharged.


Three  types  of  reverse  osmosis configurations are currently popular.
The first, known as the "spiral  wound"  configuration,  uses  flat sheet
cellulose  acetate membranes wound in a spiral to produce a multitude of
thin channels through which the feed  water  flows  under  high  laminar
shear.   This  configuration is inexpensive, produces high water fluxes,
and consequently efficient use of membrane area.  Its  major  difficulty
is that the resulting thin channels become easily fouled and plugged, so
a process stream must have a very low level of suspended solids.

The  second  configuration  uses  tubular cellulose acetate membranes to
bring about turbulent flow and overcome concentration polarization.  The
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membrane is formed into a tube—with an inside diameter of about 1 inch,
and the "active" (salt rejecting)  face of the membrane on the inside  of
the  tube—through  which  the  feed  stream  is  recirculated  at  high
turbulent speeds.  Membrane utilization is not as efficient  as  in  the
spiral  wound  configuration,  but  there  is  less  trouble  with  flow
distribution, fouling and  plugging.   This  system  can  handle  highly
contaminated wastes with high concentrations of suspended solids.

Finally,  a  reverse  osmosis  system  using a multitude of hollow nylon
fibers has shown considerable utility on commercial  waste  streams.   A
bundle  of  fibers, with the "active" side of the nylon membranes on the
exterior of the fibers, is encased in a module.  Feed water is passed at
high velocities between the fibers, and fresh  product  water  permeates
into the interior lumens of the fibers from where it is collected.  This
configuration  results  in  rather low utilization of membrane area, but
since the cost per unit area of the membranes is considerably lower than
the cost of the cellulose acetate membranes, the ultimate cost of  water
recovery   is   competitive   for   low  salinity  feed  streams.   This
configuration, like the spiral  wound  one,  is  highly  susceptible  to
fouling  by suspended solids, and requires thorough pre-treatment of the
feed stream.

Relevance to Textile Wastes Treatment^  The major application of reverse
osmosis to textile wastes would appear to be in  removal  of  salt  from
secondary  sewage  plant  effluent.   The technology appears adequate to
reduce the effluent salts to potable levels  (less than 200  mg/1).   The
process  should  also result in excellent color removal, and substantial
removal of residual BCD and COD.  The major  limitation  appears  to  be
cost:   for  large plants, 19,000 cu m/day  (5 mgd) or greater, costs are
13 to 192/1000 liters  (50 to  750/1000  gallons).   However,  the  costs
increase greatly for smaller plants, because of greater labor costs.

The major technical limitation of the process for treatment of secondary
effluent  is  the  requirement  of  feed stream quality.  High levels of
suspended solids greatly reduce water flux rates through the  membranes,
and  increase  costs  substantially.   It will therefore be necessary to
remove the suspended  solids from the feed.  Grease and oil in the  feed
may  also  retard fluxes to some degree, although this effect reportedly
is not as great in the tubular configurations.

 In addition to treatment of secondary sewage effluent, reverse  osmosis
has  been  considered  for  a  number  of  other applications in textile
wastes.   An  experimental  hollow-fiber  reverse-osmosis  pilot   plant
operates  on  the total waste stream from a textile plant.  This system,
which has allowed 80% recovery of the product  water,  with  good  color
removal.   Data  on  flux  rates,  cost,  or  longevity is inadequate to
extrapolate to the ultimate utility of the process.  It is expected that
flux decline, because of suspended solids, may be a problem, and COD may
not be removed adequately.
                                  97

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Another potential application of reverse osmosis is recovery  of  sizing
materials.  Carboxymethylcellulose (CMC)  and polyvinylalcohol (PVA)  will
both  be retained at great efficiency by reverse osmosis,  allowing these
sizing materials to be concentrated for reuse.   The savings  from  reuse
of  these  sizing streams may offset the costs  of the smaller plants re-
quired to process just the sizing waste streams.


Ultrafiltratjoni  Ultrafiltration is similar to reverse osmosis in  that
it  relies  on  the permeation of water through a semipermeable membrane
under a hydraulic driving pressure.   The  distinction  between  reverse
osmosis  and  Ultrafiltration lies primarily in the retention properties
of  the  membranes:   reverse  osmosis  membranes  retain  all  solutes,
including   salts,   while   Ultrafiltration   membranes   retain   only
macromolecules and suspended solids.    Thus  salts,  solvents,  and  low
molecular  weight organic solutes pass through  Ultrafiltration membranes
with the permeant water.  Since salts are not retained by the  membrane,
the  osmotic  pressure  differences across Ultrafiltration membranes are
negligible.  Flux rates through the membranes usually are  fairly  high,
and  hence  lower  pressures  can  be used than are practical in reverse
osmosis.  Typical pressure driving forces for Ultrafiltration are 20  to
100 psi.

Membranes may be made from cellulose acetate, polyelectrolyte complexes,
nylon,  or a variety of inert polymers.  Hence, highly acidic or caustic
streams may be processed, and the process  is  not  usually  limited  by
chemical attack of the membranes.


Relevance  to  Textile  Waste Treatment^  Since Ultrafiltration does not
remove  salts  and  low  molecular  weight  organic  compounds  such  as
dissolved  dyes,  its utility in textile waste treatment would appear to
be limited to macromolecules and suspended solids.

Concentration and recovery of disperse dyes by  Ultrafiltration  may  be
feasible,   where  a single color is in the waste stream.  concentration
of polymeric cotton  sizing  materials   (PVA  and  CMC)  is  technically
feasible  since  the  UF membranes will retain the polymers and pass the
polymer-free water at reasonable  fluxes.   An  experimental  system  is
being   used   to   test   the   feasibility  of  PVA  concentration  by
Ultrafiltration, with the ultimate aim of re-using the  sizing  polymer.
The  membrane  in this system is a new experimental "dynamically formed"
membrane based on deposition of organic surfactants  on  porous  carbon,
but  the process should be feasible on more conventional UF membranes at
a cost of 132 to 260 per 1000 liters  (502 to $1.00 per thousand gallons)
of water removed.
                                  98

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Electrodialysis:  The production of potable water from  brackish  waters
by  electrodialysis  is  a  mature desalting process.  Economically,  the
process is usually limited to feed waters having total dissolved  solids
up  to  10,000 mg/1 and more commonly it treats waters with 1000 to 2000
mg/1 solids.  It is not practical to reduce  the  total  solids  in  the
produce water to a few rrg/1 as is done in distillation plants; about  200
mg/1 is the highest purity attainable in a practical plant.

The  general  principles of electrodialysis are as follows.  The process
involves the separation of a given flow cf  water  containing  dissolved
and ionized solutes into two streams, one more concentrated and one more
dilute  than  the original, by specially synthesized semi-permeable mem-
branes.  Some ion exchange membranes  are  permeable  only  to  cations;
thus,  only  positive ions will migrate through them under the influence
of an electric  field.  Other ion exchange membranes, permeable only   to
anions, will permit migration of negative ions only.

In electrodialysis, water is fed, usually in parallel, into the compart-
ments  formed  by  the  spaces  between alternating cation permeable  and
anion permeable membranes held in a stack.  At each end of the stack   is
an  electrode  having  the  same area as the membranes.  A d-c potential
applied across the stack  causes  the  positive  and  negative  ions   to
migrate  in  opposite  directions.   Because  of  the  properties of  the
membranes, a given ion will either migrate to the  adjacent  compartment
or  be confined to its original compartment, depending on whether or  not
the first membrane it encounters is permeable to it.  As a result, salts
are concentrated or diluted in alternate compartments.

To achieve high throughput, the electrodialysis cells  in  practice  are
made  very  thin and assembled in stacks of cells in series.  Each stack
consists of more than 100 cells.  Feed water is first filtered to remove
suspended particulate matter which could clog the  system  or  foul  the
membrane  and, if required, is given an ion exchange treatment to remove
oxidizing materials such as ferrous or manganous ions which would damage
the membranes.  Very high organic  levels  may  also  lead  to  membrane
fouling.   The  catholyte stream is commonly acidified to offset the  in-
crease in pH which would normally occur within the cell,  and  an  anti-
scaling  additive  may  be required as well.  An operating plant usually
contains many recirculation, feedback and control  loops  and  pumps   to
optimize  the  concentrations  and  pH's  at  different  points and thus
maximize the overall efficiency.

Relevance	to	Te xti lg	Wa^te	Treatment   The   mechanism   of   the
electrodialysis  process  limits  it to the removal of relatively small,
mobile, ionized constituents from the waste stream.  Sodium,  potassium,
chlorides and sulfates readily pass through the membranes.  Larger ions,
and  those  doubly  charged,  such as phosphate, calcium or barium, have
limited mobility in the membranes and tend to remain in the feed stream.
There may be  some  incidental  transport  of  small  dissolved  organic
                                  99

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species   through   the   membranes   but   it   is   not   significant.
Electrodialysis has been used successfully for more  than  a  decade  to
convert  brackish  (2000-5000 mg/1 TDS)  water to potable water (  500 mg/1
TDS).  While this does not represent a waste water treatment application
per se, it can provide useful reliability and cost data  from  the   150
plants which have been built.


Unfortunately,  electrodialysis has not been used to treat textile plant
wastes although some efforts have been made  to investigate its   use  in
dye  removal.   Because  of their large molecular size, dye materials do
not traverse the membranes readily.  There may be  some  possibility  of
using  electrodialysis to remove dissolved salts from dye solutions, but
this has not yet been demonstrated.


Suspended solids in the feed stream are  undesirable.   High  levels  of
organic  materials  must  be  avoided  as they may attack the membranes.
Thus feed water to the plant should have a low BOD  and  COD  and  these
will not be substantially changed by the process.


                            Sorption Systems

This  group  of  advanced  waste  treatment  processes is concerned with
methods in which the waste water is  contacted  with  a  material  which
sorbs  components of the water.  The material is usually regenerated and
the sorbed material ejected into a gaseous or more  concentrated  liquid
waste   stream.   The  concentrated  liquid  waste  stream  is  normally
converted to a solid  waste  by  evaporation.   Such  processes   include
adsorption on activated carbon and ion exchange.

Activated	Carbonj.  Activated  carbon  is  a  commercially available and
particularly versatile absorbent primarily because of its relatively low
cost (22 to 1102/kg or 10 to 500/lb) and large surface area  (about  112
hectares  per kilogram or 126 acres per pound)  which relates directly to
its capacity for adsorbed material  (0.7 to  0.9  kilograms  of  adsorbed
material per kilogram of carbon) .

The  most  popular  form  of  activated carbon is the granular,  which is
easily handled, deposits the minimum of fines into the water stream, and
may be regenerated by heat with less than 10% loss per cycle.   However,
attempts  are  being  made to develop techniques for the use of  powdered
carbon, which is considerably less expensive (about  220/kg  or   100/lb)
than  granular  carbon   (662/kg  or  300/lb)  but  which is difficult to
separate efficiently from the waste water and regenerate.

Activated carbon, while acting largely as  a  general  adsorbent,  shows
some selectivity:
                                  100

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         Strongly Adsorbed                   Weakly adsorbed

         weak electrolytes                   strong electrolytes
         sparingly soluble materials         very soluble materials
         high molecular wt. compounds        low molecular wt.  compounds

The amount of a given material absorbed is a function of its chemical
nature, the amount in solution, the pH and the temperature.

Typical  adsorption capacities of activated carbon at different residual
COD levels are illustrated in Figure 8.

Several  types  of  water  carbon  contactors  have  been  proposed  and
utilized.  Usually one cr more fixed bed columns are linked in parallel.
Carbon  capacity  is  utilized more efficiently by placing several fixed
bed columns in series, the spent upstream column being replaced  with  a
regenerated  column  at  the  downstream side as appropriate.   A recent,
more efficient development is the use of moving bed systems.

The carbon is usually regenerated in multiple hearth furnaces;   in  some
cases,  such as in the adsorption of phenol, partial regeneration may be
achieved by chemical treatment.  A  schematic  of  a  treatment  process
including thermal regeneration is illustrated in Figure 9.


Relevance	to	Textile	Waste	Treatment.   The Environmental Protection
Agency has undertaken detailed studies of the use  of  activated  carbon
for  the  tertiary  treatment of municipal wastes - primarily at Pomona,
California and Lebanon, Ohio.  The Pomcna plant has been  run  for  over
four years and deserves detailed description.

The plant has a capacity of 1100 cu m/day (0.3 mgd) and is a four-stage,
fixed-bed, gianular activated carbon plant.

The  carbon  is  periodically  backwashed  to remove entrapped suspended
solids and regenerated when necessary after a  steady  state  adsorption
capacity of about O.U to 0.5 kilograms of COD per kilogram of carbon has
been  reached.   Carbon  losses  averaged  8 1/2 percent per cycle.  One
complete cycle of the 12,200 kilograms  (26,800 pounds) of carbon in  the
plant  is  achieved  each  year  of operation.  The effectiveness of the
plant in improving water quality is illustrated in Table 11.
                                  101

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    1-0
il
o
 JU

El
    0-1
   001
                                .--•*
                     **tf
                                          ^ >
                    _L
                                            Co  C0
      0-1
   LO            10-0

(C) Residual COD cone, (ppm)
                                                1OO-0
                    Figure 8

       COD Isotherms Using Virgin Carbon  and

       Different Secondary Sewage Effluents

             (after Masse, 1967)
                      102

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Influent
i
i
Regenerated t
Carbon
"\
j
i
1 1
V.


\
\

J
1


) * W

Carbon

t . t
1 '

Spent
Carbon
Tank
}
r

Regeneration
Furnace
I
•

Quench
Tank


Make-up
Carbon
1 1
i
Regenerated
Carbon Storage
fc, ' '
	 ^ 	 , 	
                                      Regenerated Carbon
                                     Figure 9

                   Schematic of an Activated Carbon  System
                        Including Thermal  Regeneration
                                         103

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                   Table 11

        Carbon Adsorption Pilot Plant:
       Average Water Quality Characteristics
         (June 1965 to July 1969)
      Parameter

Suspended solids mg/1

COD              mg/1

Dissolved COD    mg/1

TOC              mg/1

Nitrate as N     mg/1

Turbidity (JTU)

Color (Platinum-Cobalt)

Odor

CCE              mg/1

BOD              mg/1
Influent
9
43
30
12
8.1
8.2
28
12
__
3
Effluent
0.
10
8
3
6.
1.
3
1
0.
1
6



6
2


026

                          104

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About 75% of the influent COD is removed, and the values of  most  other
parameters such as suspended solids, turbidity,  color,  odor, and BOD are
reduced to insignificant levels.  The effluent water had an average dis-
solved COD of 8 mg/1.

Another  activated  carbon  plant  studied  by  the  EPA  is part of the
advanced waste treatment facility at the District of Columbia's advanced
waste treatment facility.  Following lime precipitation, filtration  and
water  stabilization,  the  secondary  effluent  is  passed through five
pressurized activated carbon columns in series at a rate of 190 cu m/day
(50,000  gallons  per  day).   When  the  preceding  clarification   was
operating  efficiently,  up  to 75 percent of the TOC was removed by the
carbon adsorption system.  Because of operating difficulties the  carbon
had  to  be  replaced  before  saturation,  at  a  loading of only 0.133
kilograms TOC/kilogram carbon.


Activated carbon treatment was also used successfully at Lake  Tahoe  to
produce drinkable water from secondary effluent.  A 28,000 cu m/day (7.5
million  gpd)  unit  operated  at a cost of 60/1000 liters  (230 per 1000
gallons) .

Experience with the Use of Activated Carbon on Textile Wastes.  The  use
of  activated  carbon  to treat textile wastes was pioneered at a carpet
mill, in Pennsylvania.  Of the raw waste from  the  dyeing  and  rinsing
plant,  80  percent  was treated and reused.  Capacity of the system was
1900 cu m/day  (500,000 gallons per day) and it utilized 22,700 kilograms
(50,000  pounds)   of   granular  activated  carbon.   The   carbon   was
regenerated by heating it in a furnace.

EPA  has  supported  work  in  a unique activated carbon system in which
regeneration  is  accomplished  by  backwashing  the  absorbed   organic
material into an aerobic biological treatment unit.

After  encouraging  results  in a laboratory unit operating on synthetic
textile waste water, a pilot system was installed at a carpet yarn fiber
dyeing plant.  The flow of the pilot system has a  capacity  of  190  cu
m/day  (50,000 gpd).


A  range  of studies on the treatment of dye waste waters were made by a
textile company in North Carolina.  The company encountered only partial
success in the use of carbon for effluent polishing following biological
treatment.  In this study anthracite-based media  proved  unreliable  in
removing   color  contamination;  bone  char  proved successful but cost
about $2.20 per kilogram  ($1.00 per pound) compared to 660 per  kilogram
(300 per pound) for the former materials.
                                  105

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There  are  several  further  instances  of  the use of  activated carbon
adsorption for the treatment of textile wastes,  particularly  in  regard
to  color  removal.  A mill in Pennsylvania,  operates a  closed dye cycle
using alum, diatomaceous earth, and carbon to yield a color of less than
50 units.  The consensus appears to be that while color  can  be  removed
by activated carbon, some elements (particularly the dispersed dyes)  are
not  adsorbed.   cherrical  coagulation  supplemented by  cictivated carbon
adsorption remains the best method for the dispersed dyes,  while  carbon
adsorption alone may be adequate for dissolved dyes.

To summarize, activated carbon treatment is a common technique in indus-
trial processes, has been evaluated in some detail and has  been success-
ful  in  treating  secondary  effluent following biological treatment of
municipal waste water.  Some successful experience also  has  been  accu-
mulated  in  the  treatment  of textile wastes.   The advanced process is
suitable for reducing low-level organic contamination,  but  it  affects
the levels of dissolved ionic solids very little.


Ion	Exchange.   Ion  exchangers  are  solid  materials,  insoluble  in
electrolyte solution, which are capable of exchanging soluble anions  or
cations  with electrolyte solutions.  For example, a cation exchanger in
the sodium form, when contacted with a  solution  of  calcium  chloride,
will  scavenge  the calcium ions from the solution and replace them with
sodium ions.   This  provides  a  convenient  method  for  removing  the
"hardness" from waters.

Ion exchange can also be used for total salt removal from waste streams,
by  employing  a  series  of  beds  of anion and cation  exchangers.  The
cation exchanger is used in its "acid" form,   exchanging  hydrogen  ions
for  the  cations  in  the  stream.   The anion exchanger is used in its
"base" form, exchanging hydroxyl ions for the waste strecim anions.   The
hydroxyl  and  hydrogen  ions  thus liberated from the ion exchanger re-
combine to form water, and thus replace the salts in the stream by  pure
water.


The exchange of ions on ion exchangers is stoichiometric and usually re-
versible.  Thus, after the ion exchanger becomes saturated with the con-
taminant ion, it can usually be "regenerated" by flushing with a concen-
trated  solution  of its original ion.  The waste regenerate streams are
usually quite concentrated and can be disposed of economically by simple
evaporation.

The most important class of ion exchangers, is the organic  ion-exchange
resins made  from cross-linked  polyelectrolytes.  The exchanger exchanges
the  counter  ions  to  the fixed charges on the polyelectrolyte.  These
resins are insoluble but swell to a limited degree, allowing  ions  from
                                  106

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solution  to  penetrate  into  the  gel  matrix  formed  by  the swollen
polyelectrolyte.

They are conventionally used in particulate form in  packed  beds.    The
ion  exchange  behavior of the resins depends on the nature of the  fixed
ionic groups, with the exchanger preferring those  ions  which  strongly
associate with the fixed ions.

One  of  the major advantages of the synthetic resins is the wide ranges
of ion exchange properties which can be built into them,  allowing   con-
siderable latitude in the designing of processes.  These exchangers have
the additional advantage of being capable of absorbing non-ionic organic
solutes from solution.

In general, ion exchange processes are limited by the selectivity of the
exchanger  for  the  contaminant ion over its own counter ion.  Divalent
ions such as calcium and magnesium in general have high  affinities  for
the  ion  exchange  resins,  and can therefore be removed with extremely
high efficiencies.  In general, also, ion  exchange  is  less  efficient
than  electrodialysis or reverse osmosis for high concentration streams.
An upper limit frequently given for efficient removal  of  ions  by  ion
exchange  is  200-500 mg/1, but others quote efficient cleansing of 2500
mg/1 streams at costs less than  that  for  electrodialysis  or  reverse
osmosis.

Relevance	to  Textile Waste Water Treatment.Direct data on the applica-
bility of ion exchange to textile wastes is  scarce.   Extrapolation  of
data  from  other waste streams is therefore necessary.  It would appear
that the major application of ion exchange to  textile  waste  treatment
would  be  to reduce the dissolved solids level of the effluent from the
secondary treatment plants or the effluent from other operations such as
electrodialysis or reverse osmosis.  The dissolved solids levels of  the
secondary  sewage  effluents  would appear to be in the proper range for
effective use of ion exchange.  Costs for a 50 percent reduction of this
salinity, assuming no other complications, would be expected to be  about
120/1000 liters (450/1000 gallons) of product water, not  including  the
cost  of  evaporating  the  concentrated  regenerate waste stream.   This
latter is estimated to be of the order of 3 to 5 liters of  concentrated
waste  saline  per  1000  liters of feed water.  Recently, a new form of
organic ion exchange resin has been developed which may allow economical
de-ionization of waste streams at dissolved salt levels of 1000 to   3000
mg/1.   This  "Desal"  process  is based upon the discovery that certain
weakly basic anion exchange structures can  form  the  bicarbonate   salt
with  solutions  of  carbon dioxide, and also have a favorable chloride-
bicarbonate selectivity coefficient.  The process relies on a series  of
three ion exchange beds.

This  process has been operated successfully at the pilot plant scale on
brackish water; the concentration was reduced to a final effluent of  20
                                  107

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to 30 mg/1, at an operating cost estimated to be equivalent to 5.30/1000
liters  (20 0/  1000  gallon)  (1970)  and a total capital investment for a
3785 cu m/day (1-mgd) plant of about $250,000  (  1970).    A  commercial
plant  achieving  similar results was operating in the United States for
several years.

More  conventional  icn  exchange  resins  have  been   used   for   the
desalination  of  brackish  water.   A  pilot plant operation at Pomona,
California has reduced the salinity of tertiary sewage from 1500 to  250
mg/1  with an estimated cost (based on a 37850 cu m/day or 10-mgd plant)
reported to be 2.6 to 6.10/1000 liters (10-230/1000 gallons).


Recently,  countercurrent ion exchange has begun to  make   an  impact  on
American  ion  exchange  technology.  This process allows more efficient
use of regeneration chemicals,  and therefore significantly reduces  cost
and  pollution  by  regeneration  waste  streams.   Apparently, European
manufacturers of ion exchange equipment have recognized the savings  for
some  years and have incorporated the new technology into their systems.
It has been predicted that this technology  whose  success  relies  upon
novel  methods  of  preventing  fluidization  of  the ion exchange resin
particles during back flow, will soon become dominant  in  U.S.  markets
also, and will lower the cost of ion exchange use.  It is predicted that
the  cost  of  reducing the salinity of waste water containing 1000 mg/1
NaCl to 250 mg/1 will be 10 to 120/1000  liters   (40-450/1000  gallons),
including amortization of equipment, labor costs, chemicals, etc.


One  additional  advantage  of  ion  exchange  is  applicable  to highly
alkaline textile waste streams.  For example, if the effluent is  sodium
hydroxide the cation exchanger alone may be used.


Thus  it may be advantageous, where possible, to leave the alkalinity in
the hydroxide form  and removing it by ion exchange.


The quality of the waste stream necessary to make ion exchange  feasible
is  a  major factor in its usefulness.  The level of suspended solids in
the waste stream can have a considerable deleterious effect on the long-
term operation of the  ion  exchange  columns.   It  will  therefore  be
necessary to filter suspended solids  to a low level before allowing the
water  to  enter  the ion exchange columns.  Any oxidizing agents in the
waste stream will have an adverse effect  on  the  life  of  the  cation
exchangers, while organic constituents may shorten the life of the anion
exchange resins.
                                  108

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It  appears,  however, that the projected costs of ion exchange for tex-
tile waste clean-up are sufficiently low to justify a study to determine
long-term applicability.

                         Chemical Clarification

Suspended solids are a significant element of  raw  textile  mill  waste
water.   The  larger  components  such  as  lint  are readily removed by
screens prior to entering a waste water treatment process.   Residence in
a clarifier permits other smaller yet macroscopic particles to settle as
a sludge.   Following activated sludge treatment and  clarification  the
waste water still contains a variety of  suspended solids.   These may be
removed by chemical clarification methods, which, in addition, have been
found to be effective for color removal.

Textile  wastes typically contain a complex mixture of suspended solids/
mostly of organic composition.  They  include  color  bodies,  proteins,
soaps,  fibers,  mineral  fines, oil and grease.  Carpet mill wastes can
contain considerable guantities of latex.  These suspended  solids  have
deleterious effects on the other advanced waste treatment processes used
in  tertiary  treatment  of waste streams; they load secondary treatment
plants, blind  sorbent  beds  and  deposit  on  membrane  surfaces.   In
themselves, they contribute undesirable properties to the waste water --
suspended COD, turbidity, color, etc.

In  addition  to the obvious difficulty of removing small particles, the
suspensions are stabilized by two effects:  hydration and  electrostatic
charge.   Most  such particles adopt a negative charge and are prevented
from coalescing to the larger, more easily removed  particles  by  elec-
trostatic  repulsion.   Neutralization of these charges destabilizes the
system and leads to coagulation and precipitation or easier  filtration.
This process is the basis for chemical clarification.

Coagulation  is generally accomplished by adding coagulants that contain
multivalent cations.  These include:

         lime, aluminum  sulfate,  ferric  chloride,  copperas,  ferrous
         sulfate, ferric sulfate and scdium aluminate.

The  multivalent cations A1+++, Fe+++ and Fe-n- are strongly hydrated and
hydrolyzed, forming acidic solutions.  Sodium aluminate,  on  the  other
hand,  forms  a  strongly  alkaline  solution  and  is sometimes used in
combination with aluminum sulfate to improve the resulting floe.


Addition of  coagulants to the suspended solids and colloidal substances
produces a floe which is allowed to settle in a clarifier  using  gentle
agitation.   It  is  important to dissipate the coagulant throughout the
                                  109

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waste water as fast as possible;  flash mixing at point of entry  to  the
clarifier is normally used.

The  correct  coagulant dose for  a specific waste water and particularly
the  precise  pH  for   maximum   effectiveness   must   be   determined
experimentally.   Unfortunately,   the optimum values of these parameters
may not be the same fcr different components of the  waste  water;   thus
turbidity  removal may demand an  operating pH different from that needed
for color removal.

Coagulant aids may also be used to create larger, tougher floes that are
more amenable to sedimentation or filtration.  Activated silica has been
used for many years; more  recently,  water  soluble  polymers,  usually
polyelectrolytes,  have  been  used successfully for this purpose.   They
are available in anionic, cationic, or neutral form to  treat  floes  of
differing electrostatic characteristics.

Relevance 	to	Textile	Waste	Water	Treatment^   Coagulation  and
flocculation is a widely used technique in waste water treatment and  in
the preparation of potable water.  Costs typically range from 1-5£/ 1000
liters  (5 to 200/1000 gallons) .

Chemical  clarification  has  frequently  been  used in the treatment of
textile waste.  Apart from its use to remove suspended  solids,  it  has
found  particular  promise  in  the  removal of troublesome disperse dye
particles which are  generally  not  adsorbed  by  activated  carbon.  A
description  of  some  typical  experience  in the textile industry will
illustrate the usefulness of the process.

A two-stage flocculaticn process using ferric sulfate as a coagulant was
used to treat the combined wastes of a wool scouring and dyeing plant in
Virginia.  BOD of the combined wastes was  reduced  by  60  percent  and
suspended solids by over 90 percent.
In  Israel,  experimental results showed that flocculation with alum and
filtration would reduce color by 95% and turbidity by 97%  in  a  highly
colored  simulated  waste  water.   Performance was shown to be a strong
function of pH and alum dosage; maximum reduction of  color  levels  and
turbidity  did not necessarily occur at the same pH value.  The Cationic
polyelectrolytes were found to be affective coagulant aids, but only  at
very high doses  (about 30 mg/1) .

The treatment of wool processing effluent using coagulants has been dis-
cussed  by  Stewart.   Calcium  chloride coagulation was used in a plant
England.  Addition  of  2,000  mg/1  of  calcium  chloride  followed  by
filtration  reduced  a  BOD  of  15,000 to 30,000 mg/1 to 2,700 to 3,800
                                   110

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mg/1, suspended solids cf 20,000 to 32/000 mg/1 to 1,000 mg/1 and grease
levels of 17,000 to 20,000 mg/1 to 50 mg/1.  But the cost was over $1.30
per 1000 liters ($5 per 1,000 gallons)  in 1964.


In a review of treatment methods for dye waste waters,  it  was  reported
that  the  most  successful  coagulation  technique  for  color  removal
consisted of the use of alum or a combination of  alum  and  a  cationic
polyelectrolyte.   Treatment of wastes before and after activated sludge
treatment was studied; in general, less chemical requirement  was  found
prior  to  biological  treatment.   Mixed liquor treated with 150 to 250
mg/1 alum, 10 mg/1  lime  and  20  mg/1  cationic  polymer  produced  an
effluent  color  with zero suspended solids,  but the chemical cost alone
was 2.1 to 2.60/1000  liters   (8  to  100/1000  gallons).   If  chemical
clarification must follow biological treatment, 200 to 400 mg/1 alum and
no coagulant aid may be used.  Color removals of about 95 percent can be
expected.

The  use  of a polyelectrolyte has been found to be a useful aid to alum
dewatering in other work.

A company in Pennsylvania reports successful  color removal of  a  closed
dye  cycle  water  using  a  combination of alum treatment, diatomaceous
earth filtration and carbon adsorption.
                                  111

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                              SECTION VIII

              COST, ENERGY, AND NON-WATER QUALITY ASPECTS

           Reduction  Benefits  of  Alternative  Treatment  and  Control
Technologies                                                  ~

A  detailed  economic analysis showing the cost effectiveness of various
treatment and control technologies upon the seven  subcategories  within
the  Textile  industry  is  given  in  this  document.   Five alternative
treatment methods have been considered for Subcategories 1  to  7.   For
the seven subcategories, the alternatives include:

    Alternative A - No waste treatment or control.

    Alternative B - Preliminary and biological treatment.


    Alternative C - Multi-media Filtration

    Alternative D - Activated Carbon Adsorption

    Alternative E - Multiple Effect Evaporation and Incineration.

Basis	of__Economic	Analysis  - Following is a summary of the basis for
cost estimates:

    1-   Investment - Investment costs  have  been  derived  principally
         from published data on waste water treatment plant construction
         costs,  consultants1  cost data, and information from equipment
         manufacturers and suppliers.

         Published  cost  data  for  treatment  facilities  is   derived
         primarily   from   experience   with   waste   water  treatment
         installations.  Cost information  has  been  reported  by  some
         textile manufacturers, but the data are not extensive enough to
         serve  as  a  basis  for the estimates presented herein.  Basic
         data were developed by preparation of  graphical  relationships
         between  cost  and  size  for  each  unit  operation.  Based on
         treatment plant configuration, design criteria, and size, costs
         for individual unit operations were added together to determine
         major facility costs.

         An allowance of 15 percent of the  total  investment  has  been
         included  as  yardwork which includes general site clearing and
         grading inter-component piping, lighting,  control  structures,
         road paving, and other items outside the structural confines on
         an  individual  plant component.  An additional allowance of up
                                  112

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     to 25 percent of the total  investment  has   been  included   to
     cover land,  contingencies,  engineering and overhead.

2.    Depreciation, and_CQst_Qf_Capital_(Integest)  -  It  was  assumed
     that   the   annual   interest  costs  (cost  of   capital)   and
     depreciation would be constant over the life of  the   treatment
     facilities.   A principal repayment  period of 10 years  was  used.
     Costs  were   depreciated  on  a  straight line  basis  and  the
     depreciation period of  10  years  was  assumed  equal  to  the
     principal  repayment  period  and  the  economic   life  of  the
     facilities.

     Cost of money was assumed to be an  average of the cost of  debt
     capital  and  the cost of equity capital.  Cost of debt capital
     was assumed  to be 8 percent and the cost of  equity capital   22
     percent.   Data  for the last 10 to 12 years indicated that  the
     average net  return on equity capital for the chemical   industry
     and  other  manufacturing  has been 10 to 12 percent.   Assuming
     corporate income tax is equal  to  net  return  (50%   of  gross
     return)/  gross  return  is estimated to be  debt  capital and 40
     percent equity capital.  From this  analysis,  an   average  rate
     for the cost of money equal to 13.6 percent  was determined.   An
     average   annual  value  for  cost   of  money  was derived   by
     subtracting   the  straight  line depreciation cost   from  the
     investment  cost, times the capiral recovery factor.   The  costs
     were about 8 percent of the capital investment.

3.    Insurance_and Taxes - An annual cost of 1 1/2  percent  of  the
     initial  investment  was  used  for  insurance and taxes on  the
     waste treatment plant.

4-    Operation _and^Maintenance_Labor  -   Operation  and maintenance
     labor  manhour requirements were based mainly on  published data
     and  independent  estimates.   The    operational    requirements
     include general management and supervisory personnel,  equipment
     operators  and  laborers, and clerical and custodial  personnel.
     Maintenance  labor includes mechanical electrical, laborers,  and
     other appropriate repair personnel.

     Based on labor rates in  the  Textile  industry  and   municipal
     waste water  treatment plants an August, 1971 average  labor rate
     of $5.00 per hour (including fringe maintenance labor costs).

5.    Chemicals -   Chemical costs used in the economic   analysis  are
     based  on  published  literature typical in  the U.S.   The  costs
     used are:
     Lime - $22.00 per metric ton ($20.00 per ton)
                              113

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         Soda Ash - $3.96 per 100 kilograms ($1.80 per 100 pounds)

         Ferric Chloride - $8.80 per 100 kilograms ($4.00 per 100
         pounds)

         Polymer - $0.44 per kilogram ($0.20 per pound)

         Chlorine - $13.20 per 100 kilograms ($6.00 per 100 pounds)

         Sulfuric Acid - $36.40 per metric ton  ($33.00 per ton)

         Ammonia - $35.90 per metric ton ($32.50 per ton)
                ~ ^n byroad context,  energy includes electric  power  and
         fuel.    Electric  power  consumption  for  major  units such as
         aeration, pumping, and  mixing  was  estimated  from  available
         data.    An  allowance  of  ten percent was made for small power
         users  such as clarifiers, chemical feed equipment,  ventilation
         equipment,  and  so  forth.   The  cost  of  electric power was
         assumed to be $0.015/kwhr.   Motor efficiency was assumed to  be
         70 percent.

         For alternative E, steam is required for evaporation.  The cost
         of steam ranged from $1.76  to $2.42/1,000 kg of steam  ($0.80 to
         $1.10/1,000 Ib of steam).

Information  on actual treatment cost experience in the textile industry
was available in varying degrees  of  completeness  from  the  exemplary
plants  visted.   To  verify  the  quality  of  the data received and to
provide a broader basis for estimation, a costing  model  was  developed
based  on  standard  waste  water treatment practice.  This model covers
both capital and operating costs for the equivalent of what  appears  to
be  the best technology currently practiced by the industry: essentially
primary and secondary treatment as extended aeration with  stabilization
ponds.   Over a plant size range of  400-12,000 cubic meters per day  (0.1
to 3.0 MGD) , the cost experience  data  from  the  plants  visited  came
within  30  percent of that predicted by the cost model, as shown by the
examples in Table 12.  The costs calculated from the  model,  therefore,
are  believed  to  be  realistic  bases for estimating the  (replacement)
value  of  existing  facilities  and  the  economic  impact  of  further
secondary-type treatment requirements.

Cost curves developed from the cost model are presented in Figures 10 to
18.    (For  very  small  plants   (about  110 cu m/day or 30,000 gpd) , an
overall cost figure of $264 for 1 cu  m/day  or  $1.00  for  1  gpd  was
assumed.)  Figures  14 to  18 present the operating and maintenance costs
over the ranges of  production  found.   The  initial  capital  cost  of
biological  treatment  systems  depends mainly upon  (and here is related
to) the hydraulic load, the other factors making only  minor  variations
                                  114

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in the total cost.  Operating costs, on the other hand,  have been viewed
as dependent on pollutant as well as hydraulic loads.

Costs  for  representative  large  plants  in  industry   categories were
developed using these  curves  and  assuming  an  aerated  stabilization
basin,  which  is  widely  used  by  the  industry  when land is readily
available.  The following  items  were  determined  for   the  individual
treatment steps:

     (1)   Construction costs as function of hydraulic land at a given
         pollutant level;

     (2)   Operating and maintenance labor as a function of hydraulic
         load;

     (3)   Chemical requirements as a function of hydraulic and pollutant load;

     (4)   Power requirements as a function of hydraulic and pollutant
         load;

     (5)   Additional material and supply cost as a function of hydraulic
         load.

Costs  have  been  adjusted  to a national average cost  level of January
1973 using the ENR Construction Cost Index.  The estimated  cost  curves
have  been  adjusted  to  exclude  unusual construction  or site-specific
requirements.   The  curves  have  been  adjusted  to  exclude   unusual
construction  or  site-specific  requirements.   The  curves include all
elements of construction cost which a  contract  bidder   would  normally
encounter  in  completing  the  waste  water  treatment.   Included  are
building  materials,   labor,   equipment,   electrical,   heating   and
ventilation,  normal  excavation and other similar items.  Also included
are the engineering costs.  The annual operating costs include operation
and maintenance labor, chemicals,  power,  material  and  supplies,  and
depreciation.
                                  115

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                                          TABLE   12

                        Accuracy Of Standardized  Costing  Methodology
Example Plant
    EPA
cost estimate
  company reported
cost for actual  plant
  Ratio
   EPA
reported
Plant A (0.394 MGD)
Subcategory 1
  Aeration basin
  Aeration equipment
  Clarifier
  3 day lagoon

    yard work (15% const)
    engineering
Plant Q (2.5 MGD)
Subcategory 4
  Aeration
  Aeration equipment
  Clarifier
  3 day lagoon

    yard work (15% const)
    engineering
Plant X (1.7 MGD)
Subcategory 5
  Aeration basin
  Aeration equipment
  Clarifier
  3 day lagoon

    yard work (15% const)
    engineering
  $ 27,000
   136,900
    35,600
    12.500
  $212,000
    31,800
    42,400
  $286,200
  $ 59,000
   123,400
   116,400
     3,200
  $330,800b
    49,600
    60,000
  $440,400
 $ 57,000
   23,600
   98,800
   27,000
 $206,400
   31,000
   47.000
 $284,400
                                                           $210,000
                              1.36
                                                           $554,000
                              0.79
                                                           $335,400
                               .85
(Land cost left off these estimates  in  order to  compare with  plant  reported
 cost—maximum land cost, plant Q,  is  $6,000)
                                         116

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 1,000,000
o
0
  100,000
o
o
   10,000
                                                                 10.0
                           Figure 10

           Aerated  Stabilization Basin Construction  Cost
                                117

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    10,000
_    1,000
o
O
O)
c
       100
        10
           100
1,000                 10,000

 Total Construction Cost, ($000)
100,000
                                    Figure 11

                                Engineering Costs
                                          118

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o
Q
   10 x 105
   1 x 105
                                                       ENR Index = 1811.93,

                                                             Jan. 1973
           1.0
 10.0                100.0

       Flow, mgd



       Figure 12

Clarifier Capital Cost
                                         119

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   10x103
   1.0x10
o
o
         1,000
                                   i  i  i i
                                            ENR Index = 1811.93, Jan. 1973
    10,000


BOD removal, Ib/day
                                                                   ii  i i
100,000
                                      Figure 13

                           Aerated Stabilization  Basin

                            (Aeration Equipment Only)
                                       120

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  10,000
o
.c
c
ra
i  1,000
    100
       1.0
Operation
              Maintenance
                      i	i   i  i  I  i I
                      10.0


                     Flow, mgd
                                                                 100.0
                                  Figure  14

                          Aerated Stabilization Basin

                      Annual Operation and Maintenance Labor
                                    121

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  10,000
o
Q
o  1,000
            Chemicals for "Typical" Plants
          ENR = 1811.93, Jan. 1973
    100
                              i  i  i  i
                                                           Material &

                                                           Supply Costs
        1.0                            10.0

                                    Flow, mgd


                             Figure 15


                   Aerated  Stabilization Basin

                (Material and Supply Costs,  Annual)

                           (Chemical Costs)
100.0
                                     12?

-------
  100,000
o
Q
Q  10,000
3
C
C
    1,000
        1,000
              10,000

          BOD removal, Ib/day

        Figure  16


      Aeration Equipment

      Annual Power Costs

(Aerated  Stabilization Basin)
100,000
                                    123

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  10,000
D
o

c
0!
  1,000
c
c
              Operation
    100
      1.0
                   Maintenance
  10.0

Flow, mgd
100.0
                               Figure  17

                      Clarifier,  Annual Operation

                          and  Maintenance Labor
                                  12 ^

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  100,000
o
Q
  10,000
c
   1,000
                                            Material and Supply Costs
         1.0                           10.0

                                     Flow, mgd

                                Figure 18


                                Clarifier
                 (Material and Supply Costs,  Annual)

                         (Major Chemical Costs)
100.0
                                   125

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	of Treatment Alternatiyeg

Alternative A - No Waste Treatment or Control


Costs - None

Reduction Benefits - None

Alternative B - Preliminary and Biological Treatment

This  alternative  includes preliminary screening, primary clarification
(wool scouring only) and biological treatment.

Costs - The total capital investment cost is  estimated  to  range  from
$10,200  to $336,000 for the model plants. • The annual treatment cost is
estimated to range from $3,900 to $88,000.

Reduction Benefits  -  Alternative  B  represents  about  a  95  percent
reduction   in  BOD5  compared  with  Alternative  A.   There  are  also
significant reductions in TSS and  some  reduction  of  COD.   Oils  and
grease are reduced from wool scouring operations.

Alternative C - Multi-media Filtration

This  alternative  consists  of  a filtration process that is compatible
with biological treatment (Alternative B).

Costs - Alternative C represents a  total  capital  investment  of  from
$10,000  to  $140,000  over  Alternative B costs and an increased annual
cost estimated to range from $3,000 to $41,300.


Reduction Benefits - Alternative C represents  a  further  reduction  in
BOD5  and  TSS  due  to  solids  removal  and  optimum  control over the
biological treatment system.

Alternative D - Activated Carbon Adsorption

Alternative D includes an activated carbon adsorption  system  including
carbon   regeneration   facilities.   This  system  is  compatible  with
biological  treatment   (Alternative  B)  and  may   reguire   filtration
 (Alternative C) .  It may also be used for total eff luent treatment.

Costs - Alternative D represents a total capital investment which ranges
from  $385,000  to  $1,050,000 over Alternatives B or C and an increased
annual cost from $113,100 to $404,800.
                                   126

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Reduction Benefits - Through Alternative D,  there are some reductions in
BOD5 and TSS.  There are significant reductions in COD,  TOG,  and color.

Alternative E - Multiple Effect Evaporation and Incineration

Alternative E includes a multiple effect (three stage)  evaporator and  a
fluid bed incinerator.  Residual solids are disposed of  by landfill.

Costs  -  The  capital investment is estimated to range  from $196,000 to
$3,148,00 and annual costs  are  estimated  to  range  from  $95,000   to
$2,210,000.

Reduction  Benefits - There would be complete removal of all waste water
constituents.  There would be no waste water discharge.


Impact of Waste Treatment Alternatives on Finished_Product

Tables 13-25 illustrate  the  probable  increases  in  finished  product
prices   for   small  and  medium  size  plants  in  the  seven  textile
subcategories required to pay for waste  water  treatment.   Each  Table
lists   the   increased   cost   attributable  to  biological  treatment
(Alternative B) and the additional cost increases  in  finished  product
prices  for  multi -media  filtration   (Alternative  C) ,  activated carbon
adsorption   (Alternative  D)  and  multiple   effect   evaporation   and
incineration   (Alternative  E) .   Several  conclusions are apparent from
this economic analysis.

     (1)  The estimated increase in final  product  costs  for  the  bes
         practicable control technology currently available (Alternative
         B)  are economically feasible for small and large plants in all
         seven  subcategories.   The  estimated   final   product   cost
         increases  range  from 0.1 to 0.8 cents per kilogram of product
         (0.2  to  1.8  cents  per  pound  of   product)   for   various
         subcategories.  The average increase is less than 0.4 cents per
         kilogram  (0.9 cents per pound).

     (2)  The estimated increase in final product costs  for  multi-media
         filtration   (Alternative  C)   are significantly less than costs
         for Alternative B.  These costs are not excessive and should be
         economically  achievable  for   all   plant   sizes   in   each
         subcategory.   The maximum cost for any industry model plant is
         less than 0.4 cents per kilogram  of  product  (0.8  cents  per
         pound of product) .

     (3)  The price increases attributable to activated carbon adsorption
         appear to create an unequal  economic  impact.   Variations  in
         unit  costs  for  small industry plants as compared with medium
         sized plants are reflected in an average price increase  for  a
                                  127

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         small plant of 4.2 cents per Kilogram of product (1.9 cents per
         pound  of  product)   as compared with an average price increase
         for a medium sized plant of 2.3 cents per kilogram  (1.0  cents
         per  pound).   The  diseconomy  of  scale  with  the associated
         unequal economic impact resulted (as discussed  in  Section  IV
         and  later  in  sections  IX  and  X)   in further segmentation.
         Different effluent limitations have been established for  small
         plants   than   for   medium  or  large  sized  plants  in  six
         subcategories.

    (4)   The  estimated  price  increase  in  final  product  costs  for
         evaporation  and  incineration  (Alternative  E)   appear  to be
         excessive for all industry subcategories except  wool  scouring
         (subcategory  1) .   The  average  price  increase; for all model
         plants is 7.5 cents per kilogram product (16.5 cents per  pound
         of  product).   However,  the  average  price increase for wool
         scouring plants is 1.8 cents per kilogram(4.C cents per pound).
         Thus,  no  discharge  of   pollutants   via   evaporation   and
         incineration  is  a  feasible  alternative  treatment  for wool
         scouring plants.

Tables 13-25 indicated the  additional  price  increases  for  the  best
available  technology  economically  achievable  range  from 0.05 to 0.4
cents per kilogram (0.1 ro 0.8 cents per pound)  product processed by all
plants in subcategory 3 and by small plants in  subcategories  1,2,4,5,6
and 7 with capacities less than 6,500 kg/day (14,300 Ib/day), 900 kg/day
(1,980  Ib/day),  1,000  kg/day    (2,200  Ib/day),  3,450  kg/day (7,590
Ib/day), 3,450 kg/day  (7,590 Ib/day), and 3,100  kg/day   (6,280  Ib/day)
respectively.   For  larger  plants in the industry, the price increases
ranged from 0.4 cents per kilogram  (0.8 cents per pound)  to  a  high  of
2.0 cents per kilogram  (4.5 cents per pound).  The overall costs of best
practicable  and best available technology is estimated to range between
0.3 and 1.1 cents per kilogram  (0.6 and 2.5 cents  per  pound)   produced
from  small  plants  and between 0.5 and 2.5 cents per kilogram  (1.0 and
5.4 cents per pound)  for products from larger plants.
                                  128

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                                    TABLE   13


                         WASTE WATER TREATMENT COSTS
                         FOR SUBCATEGORY 1-(SMALL)


                                             ALTERNATIVE  (2)
Parameter/Cost                          B          C          D          E

Plant Finished Material Production
  1000 kg product/day                  6.1        6.1        6.1        6.1
 (1000 Ib product/day)                13.3       13.3       13.3        13.3

Average Water Usage
  I/kg product                        12.5       12.5       12.5        12.5
 (gal/lb product)                      1.5        1.5        1.5        1.5

Estimated Investment Cost  (1)         41.0       15.0      385.0      392.0
    ($1000)

Estimated Annual Cost                 16.0        4.4      113.1      190.0
    ($1000)

Estimated Product Cost
    $/kg product                     0.002     0.0005      0.015      0.026
    ($/lb product)                    0.005     0.001       0.034      0.057


(1)  Assumes treatment facilities sized to meet production with no
     allowance for growth.

(2)  Alternative B = Preliminary and Biological Treatment
     Alternative C = Multi-Media Filtration
     Alternative D = Activated Carbon Adsorption
     Alternative E = Multiple Effect Evaporation and Incineration
                                     129

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                                    TABLE   14


                         WASTE WATER TREATMENT COSTS
                         FOR SUBCATEGORY 1-(MEDIUM)


                                             ALTERNATIVE  (2)
Parameter/Cost                          B          C          D          E

Plant Finished Material Production
  1000 kg product/day                 30.3        30.3      30.3        30.3
 (1000 Ib product/day)                66.7        66.7      66.7        66.7

Average Water Usage
  I/kg product                        12.5        12.5      12.5        12.5
 (gal/lb product)                      1.5         1.5       1.5        1.5

Estimated Investment Cost (1)        103.0        38.0     480.0      768.0
   ($1000)

Estimated Annual Cost                 30.0        11.2     135.6      398.0
   ($1000)

Estimated Product Cost
    $/kg product                     0.001      0.0002     0.004      0.011
   ($/lb product)                    0.002      0.001      0.008      0.024


(1)   Assumes treatment facilities sized to meet production with no
     allowance for growth.

(2)   Alternative B = Preliminary and Biological Treatment
     Alternative C = Multi-Media Filtration
     Alternative D = Activated Carbon Adsorption
     Alternative E = Multiple Effect Evaporation and Incineration
                                      130

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                                     TABLE   15


                          WASTE  WATER TREATMENT COSTS
                          FOR SUBCATEGORY 2-(SMALL)


                                             ALTERNATIVE (2  )
 Parameter/Cost                           B           C           D          E

 Plant  Finished  Material  Production
   1000 kg  product/day                   8.2         8.2        8.2        8.2
,  (1000 Ib  product/day)                 18.1        18.1       18.1       18.1

 Average Water Usage
   I/kg product                        115.1       115.1      115.1      115.1
  (gal/lb product)                      13.8        13.8       13.8       13.8

 Estimated  Investment Cost (1)         164.0        60.0      450.0    1,316.0
    ($1000)

 Estimated  Annual  Cost                  46.0        17.7      132.8      759.0
    ($1000)

 Estimated  Product Cost
     $/kg product                      0.005       0.002      0.013      0.076
    ($/lb product)                     0.010       0.004      0.029      0.168


 (1)  Assumes treatment facilities sized to meet production  with no
     allowance  for growth.

 (2)  Alternative  B = Preliminary and Biological Treatment
     Alternative  C = Multi-Media Filtration
     Alternative  D = Activated  Carbon Adsorption
     Alternative  E = Multiple Effect Evaporation and  Incineration
                                    131

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                                    TABLE   16


                         WASTE WATER TREATMENT COSTS
                         FOR SUBCATEGORY 2-(MEDIUM)


                                             ALTERNATIVE  (2)
Parameter/Cost                          B          C          p          E

Plant Finished Material Production
  1000 kg product/day                 24.7       24.7       24.7       24.7
 (1000 Ib product/day)                54.3       54.3       54.3       54.3

Average Water Usage
  1/kg product                       115.1      115.1      115.1      115.1
 (gal/lb product)                     13.8       13.8       13.8       13.8

Estimated Investment Cost (1)        336.0      135.0      910.0    2,991.0
   ($1000)

Estimated Annual Cost                 84.0       39.8      292.5    2,087.0
   ($1000)

Estimated Product Cost
    $/kg product                     0.003      0.001      0.010      0.070
   ($/lb product)                    0.006      0.003      0.022      0.154


(1)   Assumes treatment facilities sized to meet production with no
     allowance for growth.

(2)   Alternative B = Preliminary and Biological Treatment
     Alternative C = Multi-Media Filtration
     Alternative D = Activated Carbon Adsorption
     Alternative E = Multiple Effect Evaporation and Incineration
                                     132

-------
                                     TABLE   17
                          WASTE  WATER TREATMENT  COSTS
                          FOR SUBCATEGORY 3-(AVERAGE)


                                              ALTERNATIVE (2)
 Parameter/Cost                           B          C           D       	
 Plant  Finished Material  Production
   1000 kg  product/day                  1.5         1.5         1.5         1.5
,  (1000 Ib  product/day)                  3.3         3.3         3.3         3.3

 Average Water Usage
   I/kg product                         12.5        12.5        12.5        12.5
  (gal/lb product)                       1.5         1.5         1.5         1.5

 Estimated  Investment  Cost  (1)          10.2        10.0         —       196.0
    ($1000)

 Estimated  Annual  Cost                  3.9         3.0         —        95.0
    ($1000)

 Estimated  Product Cost
     $/kg product                      0.002       0.001         —       0.044
    (S/lb product)                     0.004       0.003         —       0.100


 (1)  Assumes treatment facilities sized to  meet  production  with no
     allowance for growth.

 (2)  Alternative  B =  Preliminary and  Biological  Treatment
     Alternative  C =  Multi-Media Filtration
     Alternative  D =  Activated Carbon Adsorption
     Alternative  E =  Multiple Effect  Evaporation and Incineration
                                     133

-------
                                    TABLE   18


                         WASTE WATER TREATMENT COSTS
                         FOR SUBCATEGORY 4-(SMALL)


                                             ALTERNATIVE  (2)
Parameter/Cost                          B          C          D          E

Plant Finished Material Production
  1000 kg product/day                  2.5        2.5        2.5        2.5
 (1000 Ib product/day)                 5.6        5.6        5.6        5.6

Average Water Usage
  I/kg product                       150.1      150.1      150.1      150.1
 (gal/lb product)                     18.0       18.0       18.0        18.0

Estimated Investment Cost (1)        103.0       38.0      450.0      768.0
   ($1000)

Estimated Annual Cost                 30.0       11.2      145.8      398.0
   ($1000)

Estimated Product Cost
    $/kg product                     0.008      0.003      0.039      0.107
   (S/lb product)                    0.018      0.007      0.087      0.237


 (1)  Assumes treatment facilities sized to meet production with no
     allowance for growth.

 (2)  Alternative B = Preliminary and Biological Treatment
     Alternative C = Multi-Media Filtration
     Alternative D = Activated Carbon Adsorption
     Alternative E = Multiple Effect Evaporation and Incineration

-------
                                    TABLE   19


                         WASTE WATER TREATMENT COSTS
                         FOR SUBCATEGORY 4-(MEDIUM)


                                             ALTERNATIVE  (2)
Parameter/Cost                          B          C          D          E

Plant Finished Material Production
  1000 kg product/day                 12.6       12.6       12.6       12.6
 (1000 Ib product/day)                27.8       27.8       27.8       27.8

Average Water Usage
  I/kg product                       150.1      150.1      150.1      150.1
 (gal/lb product)                     18.0       18.0       18.0       18.0

Estimated Investment Cost  (1)        254.0      102.0      860.0    2,197.0
   ($1000)

Estimated Annual Cost                 74.0       30.1      372.7    1,472.0
   ($1000)

Estimated Product Cost
    $/kg product                     0.004      0.002      0.020      0.080
   ($/lb product)                    0.009      0.003      0.045      0.177


(1)   Assumes treatment facilities sized to meet production with no
     allowance for growth.

(2)   Alternative B = Preliminary and Biological Treatment
     Alternative C = Multi-Media Filtration
     Alternative D = Activated Carbon Adsorption
     Alternative E = Multiple Effect Evaporation and Incineration
                                     135

-------
                                            TABLE  20
                                  WASTE WATER TREATMENT COSTS
                                  FOR SUBCATEGORY 5-(SMALL)
 Parameter/Cost

Plant Finished  Material Production
   1000 kg product/day
  (1000 lb product/day)

Average Water Usage
   I/kg product
  (gal/lb product)

Estimated Investment Cost  (1)
    ($1000)

Estimated Annual Cost
    ($1000)

Estimated Product Cost
     $Ag product
    ($/lb product)
       ALTERNATIVE  (2)
  B          C          D          E
  6.8
 15.0
166.8
 20.0

160.0
 44.0
  6.8
 15.0
166.8
 20.0

 74.0
 21.8
  6.8
 15.0
166.8
 20.0
135.6
  6.8
 15.0
166.8
 20.0
480.0    1,496.0
960.0
0;004      0.002      0.014      0.097
0.010      0.005      0.030      0.213
 (1)  Assumes treatment  facilities  sized  to meet production with no
     allowance for growth.

 (2)  Alternative B = Preliminary and Biological Treatment
     Alternative C = Multi-Media Filtration
     Alternative D = Activated Carbon Adsorption
     Alternative E = Multiple  Effect Evaporation and Incineration
                                           136

-------
                                    TABLE  21


                         WASTE WATER TREATMENT COSTS
                         FOR SUBCATEGORY 5-(MEDIUM)


                                             ALTERNATIVE  (2)
Parameter/Cost                          J3          C          D          ..E. _.

Plant Finished Material Production
  1000 kg product/day                 18.2       18.2       18.2       18.2
, (1000 Ib product/day)                40.0       40.0       40.0       40.0

Average Water Usage
  I/kg product                       166.8      166.8      166.8      166.8
 (gal/lb product)                     20.0       20.0       20.0       20.0

Estimated Investment Cost (1)        327.0      140.0      910.0    3,148.0
   ($1000)

Sstimated Annual Cost                 88.0       41.3      267.5    2,210.0
   ($1000)

Sstimated Product Cost
    $/ kg product                    0.003      0.002      0.010      0.084
   ($/ Ib product)                   0.007      0.003      0.022      0.184


!l)  Assumes treatment facilities sized to meet production with no
     allowance for growth.

[2)  Alternative B = Preliminary and Biological Treatment
     Alternative C = Multi-Media Filtration
     Alternative D = Activated Carbon Adsorption
     Alternative E = Multiple Effect Evaporation and Incineration
                                       137

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                                    TABLE  22


                         WASTE WATER TREATMENT COSTS
                         FOR SUBCATEGORY 6-(SMALL)


                                             ALTERNATIVE  (2)
Parameter/Cost                          B          C          D          E

Plant Finished Material Production
  1000 kg product/day                  5.4        5.4        5.4        5.4
 (1000 Ib product/day)                11.9       11.9       11.9        11.9

Average Water Usage
  I/kg product                        70.1       70.1       70.1        70.1
 (gal/lb product)                      8.4        8.4        8.4        8.4

Estimated Investment Cost (1)        103.0       38.0      400.0      768.0
   ($1000)

Estimated Annual Cost                 30.0       11.2      116.0      398.0
   ($1000)

Estimated Product Cost
    $/ kg product                    0.004      0.001      0.015      0.051
   ($/ Ib product)                   0.008      0.003      0.032      0.111


(1)  Assumes treatment facilities sized to meet production with no
     allowance for growth.

(2)  Alternative B = Preliminary and Biological Treatment
     Alternative C = Multi-Media Filtration
     Alternative D = Activated Carbon Adsorption
     Alternative E = Multiple Effect Evaporation and Incineration
                                     138

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                                      TABLE   23


                          WASTE WATER TREATMENT  COSTS
                          FOR  SUBCATEGORY 6-(MEDIUM)


                                               ALTERNATIVE  (2)
t  Parameter/Cost                          B           C           D       	
 Plant  Finished Material  Production
    1000 kg product/day                  43.2        43.2        43.2        43.2
   (1000 Ib product/day)                 95.2        95.2        95.2        95.2

 Average Water Usage
    I/kg product                         70.1        70.1        70.1        70.1
   (gal/lb product)                       8.4         8.4         8.4         8.4

 Estimated Investment Cost  (1)         327.0       140.0     1,050.0     3,148.0
     ($1000)

 Estimated Annual  Cost                  88.0        41.3       404.8     2,210.0
     ($1000)

 Estimated Product Cost
      $/ kg product                  '  0.001      0.0006       0.006       0.035
     ($/ Ib product)                    0.003      0.001        0.014       0.077


  (1)  Assumes treatment facilities sized to meet production  with no
      allowance for growth.

  (2)  Alternative  B = Preliminary and  Biological Treatment
      Alternative  C = Multi-Media Filtration '
      Alternative  D = Activated Carbon Adsorption
      Alternative  E = Multiple  Effect  Evaporation and Incineration
                                       139

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                                    TABLE  24


                         WASTE WATER TREATMENT COSTS
                         FOR SUBCATEGORY 1- (SMALL)


                                             ALTERNATIVE  (2)
Parameter/Cost                          B          C          D          E

Plant Finished Material Production
  1000 kg product/day                  4.1        4.1        4.1        4.1
 (1000 Ib product/day)                 9.1        9.1        9.1        9.1

Average Water Usage
  I/kg product                       183.5      183.5      183.5      183.5
 (gal/lb product)                     22.0       22.0       22.0       22.0

Estimated Investment Cost (1)        125.0       59.0      400.0    1,132.0
    ($1000)

Estimated Annual Cost                 35.0       17.4      11.6.0      638.0
    ($1000)

Estimated Product Cost
    $1 kg product                    0.006      0.003      0.019      0.106
    ($1 Ib product)                   0.013      0.006      0.042      0.234


(1)  Assumes treatment facilities sized to meet production with no
     allowance for growth.

(2)  Alternative B = Preliminary and Biological Treatment
     Alternative C = Multi-Media Filtration
     Alternative D = Activated Carbon Adsorption
     Alternative E = Multiple Effect Evaporation and Incineration

-------
                                    TABLE  25


                         WASTE WATER TREATMENT COSTS
                         FOR SUBCATEGORY 7-(MEDIUM)


                                             ALTERNATIVE (2)
Parameter/Cost                          B          C          D          E

Plant Finished Material Production
  1000 kg product/day                 12.4       12.4       12.4       12.4
 (1000 lb product/day)                27.3       27.3       27.3       27.3

Average Water Usage
  I/kg product                       183.5      183.5      183.5      183.5
 (gal/lb product)                     22.0       22.0       22.0       22.0

Estimated Investment Cost (1)        277.0      120.0      730.0    2,521.0
   ($1000)

Estimated Annual Cost                 73.0       35.4      221.4    1,721.0
   ($1000)

Estimated Product Cost
    $/ kg product                    0.004      0.002      0.012      0.095
   ($/ lb product)                   0.009      0.004      0.027      0.210


(1)  Assumes treatment facilities sized to meet production with no
     allowance for growth.

(2)  Alternative B = Preliminary and Biological Treatment
     Alternative C = Multi-Media Filtration
     Alternative D = Activated Carbon Adsorption
     Alternative E = Multiple Effect Evaporation and Incineration

-------
Alternativejifreatment Systems

It has been assumed in the economic analysis that an extended biological
stabilization process will be utilized  for  the  biological  treatment.
However,  aerobic-anaerobic  lagoons  or  trickling filters or activated
sludge can  be  designed  to  provide  the  same  degree  of  biological
treatment.   These  systems  require  less area and can only be utilized
where  land  is  not  readily  available  near  the  textile   facility.
Activated  sludge  may  result  in additional annual costs of as much as
$200,000 over those costs presented for Alternative B.


It is also assumed  that  wool  scouring  plants  (Subcategory  1)   with
capacities  greater  than  6,500  kg/day   (14,300  Ib/day)  will utilize
activated    carbon    adsorption.     Table    13    indicates     that
evaporation/incineration  is  a  feasible  alternative  for  large  wool
scouring plants.  Costs could be as much as 0.6 cents  per  kilogram  of
product  (1.4 cents per pound product) higher.

Electrical Energy Requirements

The energy requirements  (electric power and fuel) for textile facilities
vary  considerably  based  upon reported data.  This varieition is due to
the following factors:

    1.   Type of fiber processed.

    2.   Type of extent of cleaning and finishing operations.

    3.   Degree of mechanization within the textile facility.

    4.   Climate of the textile location.

It is estimated that the contribution of waste treatment is considerably
less than 10 percent of the total industry energy consumption at present
and is not likely to exceed  10 percent in the future.

Thermgl_EnergY_Reguirgmentg

Thermal  energy costs are considerably less than electrical energy  costs
for  operations  within the industry.  Waste treatment syistems impose no
•significant addition to  the  thermal  energy  requirements  of  plants.
Wastewater  can  be  reused  in  cooling and condensing service if it is
separated from the process waters   in  non-barometric  type  condensers.
These  heated  waste waters improve the effectiveness of  ponds which are
best maintained at 90°F  cr  more.   Improved  thermal  efficiencies  are
coincidentally achieved  within a plant with this technique.
                                   142

-------
Wastewater  treatment costs and effectiveness can be improved by the use
of energy and power conservation practices and techniques in each plant.
The waste load increases with increased water use.   Reduced  water  use
therefore  reduced the waste load, pumping costs, and heating costs, the
last of which can  be  further  reduced  by  water  reuse  as  suggested
previously.

Solid Wastes

The  disposal  of  solid  wastes from the textile industry are generally
disposed of by landfill.  The solid materials,  separated  during  waste
water  treatment,  containing organic and inorganic materials, including
those added to promote solids separation, is called sludge.   Typically,
it  contains 95 to 98 percent water prior to dewatering or drying.   Some
quantities of  sludge  are  generated  by  both  primary  and  secondary
treatment systems with the type of system influencing the quantity.  The
following table illustrates this:
Treatment System

Dissolved air flotation

Anaerobic lagoon
Extended Aeration
Aerobic £ Aerated Lagoons

Activated sludge

Extended aeration

Anaerobic contact process
Sludge Volume as Percent of
n flaw Wastewater Volume	

 Up to 10%

 (Sludge accumulation in these
 (lagoons is usually not sufficien
 (to require removal at any time)
 10

  5
- 15%

   10%
 approximately 2%
The   raw  sludge  can  be  concentrated,  digested,  dewatered,  dried,
incinerated, land-filled, or spread in  sludge  holding  ponds.    Sludge
from  secondary  treatment  systems  is  normally  dewatered or digested
sufficiently for hauling  to  a  land  fill.   The  final  dried  sludge
materials  can  be safely used as an effective soil builder.  Prevention
of runoff is a critical  factor  in  plant-site  sludge  holding  ponds.
Costs of typical sludge handling techniques for each secondary treatment
system  generating  enough  sludge  to  require  handling  equipment are
already incorporated in the costs for these  systems.   All  other  non-
water  quality  environmental  impacts  of the alternative treatment and
control technologies described appear minor.
                                  143

-------
                               SECTION IX

               EFFLUENT REDUCTION ATTAINABLE THROUGH THE
              APPLICATION OF THE BEST PRACTICABLE CONTROL
                     TECHNOLOGY CURRENTLY AVAILABLE
                    EFFLUENT LIMITATIONS GUIDELINES

                              INTRODUCTION


The effluent limitations which must be achieved July  1,  1977,  are  to
specify  the  degree of effluent reduction attainable through the appli-
cation of the Best Practicable Control Technology  Currently  Available.
Best  Practicable  control  Technology  Currently Available is generally
based upon the average of the best existing  performance:  by  plants  of
various  sizes,  ages, and unit processes within the industrial category
and/or subcategory.  This average is not based upon  a  broad  range  of
plants  within  the  textile industry, but based upon performance levels
achieved by exemplary plants.

Consideration must also be given to:

     The total cost of application of technology in relattion to
     the effluent reduction benefits to be achieved from such
     application;

     The size and age of equipment and facilities involved;

     The processes employed;

     The engineering aspects of the application of various types
     of control techniques;

     Process changes;

     Non-water quality environmental impact (including energy
     requirements) .

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

A  further  consideration  is  the  degree  of  economic and engineering
reliability  which  must  be  established  for  the  technology  to   be
"currently  available".   As  a  result of demonstration projects, pilot
plants and general use, there must exist a high degree of confidence  in
the  engineering  and  economic  practicability of the technology at the
time of start of construction of installation of the control facilities.
                                  144

-------
           EFFLUENT REDUCTION ATTAINABLE THROUGH THE APPLICATION OF
            BEST PRACTICABLE CONTROL TECHNOLOGY CURRENTLY AVAILABLE

Based on the information contained in Section III through VIII  of  this
report,  a  determination  has  been  made  that the quality of effluent
attainable  through  the  application  of  the  Best  Pollution  Control
Technology  Currently  Available  is as listed in Table 26.  A number of
plants in the industry which have biological treatment systems for which
effluent quality data were available are meeting these standards.

A biological treatment  system  which  is  permitted  to  operate  at  a
constant  food  to  microorganism  ratio  throughout  the  year and with
minimum operational changes would have a natural variation of 50 percent
as explained in Section VII and as shown by the solid line in Figure 19.
A similar system with careful operational control and proper design  can
be  operated  within  25  percent  of the average on a monthly operating
basis,  A system without optimum operational control has  been  used  to
account  for  normal  treatment variation.  Thus, a factor of 50 percent
has been used to calculate the maximum 30 day  effluent  limitation.   A
further  allowance  of  100 percent has been applied to a maximum 30 day
effluent limitation in order  to  develop  the  maximum  daily  effluent
limitation.

-------
                                    TABLE   26

                         MAXIMUM THIRTY DAY AVERAGE
                       RECOMMENDED EFFLUENT LIMITATION
                         GUIDELINES FOR JULY 1, 1977

                                           Effluent Limitations  (1)

                                    BODS              TSS              COD
                                  kg/lOOOkg        kg/lOOOkg         kg/lOOOkg
Plant Subcategory                 (Ib/lOOOlb)       (Ib/lOOOlh)        (Ib/lOOQlb)

1.  WOOL SCOURING  (2)
    Plant capacity less than         3.7              3.7               NA
     6,500 kg/day  (14,300 Ib/day)
    Plant capacity greater than      3.7              3.7               24
     6,500 kg/day  (14,300 Ib/day)

2.  WOOL FINISHING
    Plant capacity less than         7.5              7.5               NA
     900 kg/day  (1,980 Ib/day)
    Plant capacity greater than      7.5              7.5               56
     900 kg/day  (1,980 Ib/day)

3.  GREIGE MILLS
    All plant sizes                  0.45             0.45

4.  WOVEN FABRIC FINISHING
    Plant capacity less than         2.2              6.9               NA
     1,000 kg/day  (2,200 Ib/day)
    Plant capacity greater than      2.2              6.9               33
     1,000 kg/day  (2,200 Ib/day)

5.  KNIT FABRIC FINISHING
    Plant capacity less than         1.8              8.0               NA
     3,450 kg/day  (7,590 Ib/day)
    Plant capacity greater than      1.8              8.0               24
     3,450 kg/day  (7,590 Ib/day)

6.  CARPET MILLS
    Plant capacity less than         4.3              4.3               NA
     3,450 kg/day  (7,590 Ib/day)
    Plant capacity greater than      4.3              4.3               30
     3,450 kg/day  (7,590 Ib/day)

7.  STOCK AND YARN DYEING AND FINISH-
    ING
    Plant capacity less than         3.5              9.2               NA
     3,100 kg/day  (6,820 Ib/day)
    Plant capacity greater than      3.5              9.2               47
    3,100 kg/day (6,820 Ib/day)

                               NA MEANS NOT APPLICABLE

(1)   Plant capacities and discharge limitations are stated for Subcategories
     1 and 2 per weight of raw wool received at the wool scouring or wool
     finishing operation and are stated for Subcategories 3, 4, 5, 6 and 7
     per weight of final material produced by the facility.

     For all Subcategories pH should range between 6.0 to 9.0 at any time.

     For all Subcategories Most Probable Number (MPN)  of Fecal Coliforms
     should not exceed 400 counts per 100 ml.

(2)   For all Wool Scouring plants (Subcategory 1)  Oils and Grease should
     not exceed 1.9 kg (lb)/1000 kg (Ib)  grease wool.

-------

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               IDENTIFICATION OF BEST PRACTICABLE CONTROL
                     TECHNOLOGY CURRENTLY AVAILABLE

Best  Practicable control Technology Currently Available for the textile
manufacturing industry includes preliminary screening, primary  settling
(wool   scouring  only),  coagulation  (carpet  mills  only),  secondary
biological treatment and chlorination.  Strict management  control  over
housekeeping  and  water  use practices result in raw wastes loads which
can be treated biologically to the effluent levels listed in  Table  26.
No  special  in-plant  modification  is  required.   The performances of
eighteen different  biological  treatment  systems  that  achieve  these
effluent limits are given in Table 27.

Wool Scouring and Wool Finishing

The stated guidelines for subcategory 1(wool scouring) and subcategory 2
(wool  finishing)  can  be  achieved  by  applying  the best practicable
control technology to the appropriate subcategory raw waste  load.   The
best   practicable   control   technology  for  wool  scouring  includes
screening,  settling,  biological  treatment  and   chlorination;   best
practicable  control  technology  for  wool finishing includes screening
biological treatment and chlorination.  The average raw waste BOD5  load
resulting  from  wool  scouring  is almost 50 kg (Ib) of BOD5 per 1000 kg
(Ib) of grease wool as received and weighed at the plant.   The  average
raw  waste  BOD5  load resulting from wool finishing is estimated at 100
kg(Ib)  of BOD5 per 1000 kg (Ib) of dry wool received at the plant.   The
basis  of  this  number is a single facility which is a 100 percent wool
finishing operation.   It  is  further  substantiated  by  estimates  of
knowledgeable  textile consultants.  The recommended effluent limitation
guidelines for July 1, 1977, for the wool scouring  and  wool  finishing
subcategories  are  based  on results from eighteen exemplary biological
treatment systems (see Table 27) .  These  systems  treat  textile  waste
waters  from  dyeing  and  finishing  of  broadwoven  cotton and cotton-
synthetic blends, knits and stock and yarn.
                                  149

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The average BOD5 removal efficiency of these eighteen systems is greater
than 95 percent.  The BOD5 effluent limitation is calculated by applying
this average BOD.5 removal efficiency  (95  percent)   to  the  appropriate
subcategory  raw  waste  load,  and  allowing  50 percent to account for
normal operational variation.  Thus, the BOD5  effluent  limitation  for
subcategory  1  (wool scouring)  is 3.7 kg/kkg (lb/10001b)  of grease wool
and the BOD5 effluent limitation for subcategory 2 (wool  finishing)   is
7.5 kg/kkg (lb/10001b) of dry wool.

The  subcategory  1 effluent limitations are substantiated by data given
in Table 28 for a full-scale biological treatment system at Mill A and a
pilot project at Mill B.  The treatment system at  Mill  A  can  achieve
sufficient effluent reduction to meet the effluent limitations.  This is
based  on normal water usage and production at Mill A and average 30 day
effluent BOD5 concentration of 150 mg/1.  These results are confirmed by
several months of effluent data.  Results  from  Mill  B  indicate  this
biological  treatment  system  can  also  meet the effluent limitations.
This is confirmed by several months of effluent data  during  both  warm
and  cold  weather  operation.  The subcategory 2 effluent limitation is
substantiated by water usage and waste water treatment data from a study
supported by the American Textile Manufacturers Institute, Inc., and the
Carpet and Rug Institute.

The total suspended solids  (TSS) effluent limitations are  identical  to
the  BOD5  effluent  limitations.  Results from the exemplary biological
treatment systems as well as from  Mills  A  and  B  indicate  that  the
suspended  solids  can  be  consistently reduced to at least this level.
Thus the TSS effluent limitation for subcategory 1   (wool  scouring)   is
3.7  kg/kkg   (lb/10001b)  of grease wool and the TSS effluent limitation
for subcategory 2  (wool finishing) is  7.5  kg/kkg   (lb/10001b)  of  dry
wool.

Much  of  the  chemical  oxygen  demand  (COD)  in the effluent from the
exemplary biological treatment systems and Mills A and B  is  associated
with the suspended solids in the effluent.  The COD effluent limitations
are  based  on  an  average COD effluent concentrations of 1250 mg/1 for
subcategory 1 and 325 mg/1 for subcategory  2.   Using  the  mean  water
usages  of  12.5  I/kg  (1.5 gal/lb) for subcategory 1 and 12.5 I/kg  (1.5
gal/lb) for subcategory 1 and 115  1/kg  (13.8 gal/lb)  for subcategory  2,
the  COD  effluent  limitations are 24 kg/kkg (lb/10001b)  of grease wool
for subcategory 1  (wool scour) and 56 kg/kkg  (lb/10001b) of dry wool for
subcategory 2  (wool finishing).   Effluent data from biological treatment
systems at Mills A and E confirm that these systems  can  meet  the  COD
limitation.

COD  limitations for subcategories 1 and 2 are applicable only to plants
with capacities greater than 6,500 kg/day  (14,300 Ib/day)  and 900 kg/day
(1,980 Ib/day) respectively.  As  discussed  in  Sections  IV  and  VIII
                                  151

-------
severe  diseconomies  of  scale  create  economic  impacts which require
different limitations for small plants.


Grease is a serious problem in the wool scouring subcategory.    Effluent
levels  observed especially at Mill B indicate the grease is recoverable
and treatable to levels less  than  100  mg/1  in  the  final   effluent.
Applying  this concentration to the mean water usage the grease effluent
limitation is 1.9 kg/kkg (lb/10001b)  of grease wool.

Effluent limitations for subcategories 1 and  2  include  pH  and  fecal
coliforms.    Control  cf  pH  in  the  range  of  6.0-9.0  is  commonly
encountered in treated effluents and control of fecal coliforms to  less
than 400 per 100 ml is readily accomplished by chlorination.

Greige Goods

The  stated  guidelines  for  subcategory  3 (greige goods Mills) can be
achieved by applying the best  practicable  control  technology  to  the
greige  goods  raw  waste load.  The best practicable control technology
include screening, biological treatment and chlorination.

As  described  in  Section  IV,  greige  Mills  are  essentially  a  dry
operation.   Most  greige  goods Mills discharge their waste to sanitary
systems.  Of the Mills that treat their own  waste  most  combine  their
sanitary  and  industrial  waste  loads;  the  respondees to an industry
questionnaire indicated that 70 to 90 percent of the load, was sanitary.

The only current compilation of water use figures  for  various  textile
subcategories   is  that  presented  to  EPA  by  the  American  Textile
Manufacturers Institute and the Carpet and Rug  Institute.  Although  it
has  not as yet been completely verified, it appears to present the full
range of water uses to be expected  for  each  subcategory.   Water  use
distribution  for  greige  Mills  as  shown  in  Figure 20 illustrate an
extremely wide variation.  This  can  be  explained  by  the  overriding
influences  of  nonprocess water such as boiler water, cooling water and
sanitary wastes which are  very  significant  in  some  cases  and  less
significant in others.
                                  152

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                                        Figure 20

                                 DISTRIBUTION OF WATER USE
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-------
From  the  water  usage  distribution presented, it can be seen that the
median  water  use  value  is  7.5  I/kg  (0.9  gal/lb).    It  has  been
demonstrated that BOD5 from a greige mill can be reduced to a low level.
Because  of  this high treatability and the influence of sanitary waste,
the best practicable control technology should  consistently  attain  40
mg/1  BODf>.   The  BOD5  effluent limitation can be computed by applying
this concentration factor to the median water usage and  allowing  a  50
percent  increase to account for normal operations variation.  Thus, the
BOD5 effluent limitation  for  greige  Mills  (subcategory  3)   is  0.45
kg/kkg(lb/10001b) of product.

The  total  suspended solids (TSS) effluent limitations are identical to
the BOD5 effluent limitations.   Results from  the  exemplary  biological
treatment  systems  indicated that TSS can be consistently reduced to at
least this level.  Thus, the TSS effluent limitation for greige Mills is
0.45 kg/kkg (lb/1000 Ib) of product.

These BOD5_ and TSS effluent limitations are substantiated  by  plant  I.
Two  years  of  data  indicate a BOD5 and TSS effluent discharge of less
than 0.1 kg/kkg  (lb/10001b).

Effluent limitations for  subcategory  3  (greige  Mills)  also  include
control  of  pH  within the range of 6.0-9.0 and chlorination to control
fecal coliforms to a level of 400 per 100 ml or less.

Woven Fabric Finishing

The effluent guidelines for July 1, 1977, subcategory  4   (woven  fabric
finishing)  are  the  average  of data from exemplary biological systems
treating wastes from the dyeing and finishing of broadwo>ven  cotton  and
cotton-synthetic  blends.   The  BOD5  effluent limitation is calculated
from data tabulated in Table 29 from the average of the  BOD5_  discharge
from  the  biological treatment systems at Mills J, K, M, O, Q, R, S and
U; the TSS effluent limitation is based  on  the  average  of  treatment
systems  at  Mills K, Q, and S; and the COD effluent limitation is based
on the average of treatment systems at  Mills  M,  O,  S,  and  U.   The
effluent  guidelines  for  subcategory 4 (woven fabric finishing) are as
follows:  BOD5 limitation is 2.2 kg/kkg  (lb/10001b); TSS  limitation  is
6.9 kg/kkg  (lb/10001b).

Effluent  limitations also include control of pH within the range of 6.0
to 9.0 and chlorination to control fecal coliforms below 400 per 100 ml.
                                  154

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Knit Fabric Finishing

The effluent guidelines for July 1, 1977 for subcategory 5 (knit  fabric
finishing)   are  the average of data from exemplary biological treatment
systems.   The BOD5_ and TSS effluent limitations are calculated from  the
average  of  the  BOD5  and TSS discharges from the biological treatment
systems at Mills X, Y, and Z (see Table 30).  The BOD5 and TSS  effluent
limitations  are based on these plants allowing a 50 percent increase to
account for treatment plant variation: BOD5 is  1.8  kg/kkg   (lb/10001b)
and  TSS  is  8.0  kg/kkg   (lb/10001b).   The  COD effluent discharge is
developed from data at Mills W and Y.  Approximately 70 percent  of  the
COD  is  removed  by  treatment  plants  at  these Mills.  The following
correlation was developed between monthly average COD and  BOD5_  in  the
effluent:  BOD5 limitation is 3.5 kg/kkg (lb/1000 Ib)  and TSS limitation
is 9.2 kg/kkg (lb/1000 Ib).  The COD effluent  limitation  is  based  on
three  months effluent data in which COD averaged 13 times the BOD.  The
COD effluent guidelines is 47 kg/kkg(lb/1000lb).

Effluent limitations also include control of pH within the range of 6.0-
9.0 and control of fecal coliforms to allow no more than 400 per 100  ml
of discharge.

Carpet Mills

The effluent guidelines for July 1, 1977 for subcategory 6 (carpets) are
the  average  of  data from exemplary biological systems treating carpet
mill wastes.  The BOD5, TSS and COD effluent limitations  are  based  on
the  average BOD5, TSS and COD discharges listed in Table 31 for systems
treating waste water from Mills,  MC,  BS,  CC  and  BB.   The  effluent
limitations for carpet Mills (subcategory 6) are as follows: BOD5 is 4.3
kg/kkg   (lb/1000  Ib);  TSS  is  4.3  kg/kkg  (lb/1000 Ib); and COD is 30
kg/kkg (lb/1000 Ib).

Effluent limitations also include control of pH within the range of 6.0-
9.0 and control of fecal coliforms to allow no more than 400 per 100  ml
of waste water discharge.
                                  157

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Stock and Yarn Dyeing and Finishing

The  effluent  guidelines for July 1,  1977,  for subcategory 7 (stock and
yarn)  are the average of data from exemplary biological systems treating
wastes from dyeing and finishing stock  and  yarn.    The  BOD5  and  TSS
effluent  limitations  are  based on the average BOD5 and TSS discharges
listed in Table 32 for biological treatment systems at Mills EE,  GG  and
NS.   The  effluent  guidelines  for  subcategory 7 are as follows: BOD5_
limitations is 3.5 kg/kkg (lb/1000 Ib)  and TSS limitation is 9.2   kg/kkg
effluent data in wich COD averaged 13 times the BOD5;.  The COD effluent
guidelines is 47 kg/kkg  (lb/1000 Ib).

Effluent limitations also include control of pH within the range  of 6.0-
9.0  and control of fecal coliforms to allow no more than 400 per 100 ml
of discharge.


COD limitations for subcategories 4,5,6, and 7 are  applicable  only  to
plants  with  capacities  greater than 1000 kg/day (2,200 Ib/day), 3,450
kg/day  (7,590 Ib/day), 3,450 kg/day  (7,590  Ib/day)   and  3,100   kg/day
(6,820 Ib/day) respectively.  As discussed in Sections V and VIII severe
diseconomies  of  scale  create economic impacts which require different
limitations for small plants.

                     RATIONALE FOR THE SELECTION OF
                  BEST PRACTICABLE CONTROL TECHNOLOGY
                          CURRENTLY AVAILABLE
Age and Size of Equipment and Facility

The industry has generally modernized its plants as new methods that are
economically attractive have been introduced.  No  relationship  between
age  of  production plant and effectiveness of its pollution control was
found. Size was shown in Section IV to require separate limitations  for
small  facilities  because of severe diseconomies of scale.  Differences
in effluent limitations have resulted.

Total Cost of Application in Relation to Effluent Reduction Benefits

Based on information contained in  Section  VIII  of  this  report,  the
estimated  increase  in final product costs required to achieve the best
practicable effluent reductions range from small and large plants in the
seven subcategories from 0.1 cents per kilogram product  (0.2  cents  per
pound  product)  to  a  high  of  0.8  cents per kilogram  (1.8 cents per
pound).  The average price increase is less than 0.4 cents per  kilogram
 (0.9 cents per pound) .
                                  160

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Engineering Aspects of Control Technique Applications

The  specified  level  of  technology is practicable because it is being
practiced by plants representing a wide range of plant sizes and  types.
Eighteen  exemplary  biological  treatment systems have been utilized to
develop the effluent limitations  (see Table 27).   These  systems  treat
textile waste waters from knit fabric finishing, dyeing and finishing of
broadwoven cotton and cotton-synthetic blends, carpet manufacturing,  and
stock   and  yarn  dyeing  and  finishing.   The  average  BOD_5  removal
efficiency of these systems is greater than 95 percent, this  efficiency
has  been  utilized  to  develop  limitations  in  subcategories without
exemplary  treatment  operations.   In  the  subcategories   there   are
treatment  systems  that  should be capable of meeting those limitations
with  some  modification  in  operation,  perhaps  the  presence  of   a
knowledgeable  operator.   In  general,  some minor plant design changes
along with cooperation from  management  and  plant  personnel  will  be
required.

Process Changes

Significant  in-plant  changes  will  not be needed by textile plants to
meet the specified  effluent  limitations.   Some  plants  may  need  to
improve  their  water  conservation  practices  and  housekeeping,  both
responsive to good plant mangement control.

Non-Water Quality Environmental Impact

The major impact when the option of a biological  treatment  process  is
used  to  achieve  the  limits  will  be the problem of sludge disposal.
Nearby land for sludge disposal may  be  necessary.   Properly  operated
biological  systems would permit well conditioned sludge to be placed in
small nearby soil plots for drying without great difficulty.

It is concluded that no new kinds  of  impacts  will  be  introduced  by
application of the best current technology.

Factors to be Considered in Applying Level I Guidelines

    1.   Limitations  are  based  on  30   day   averages.    Based   on
         performances of biological waste treatment systems, the maximum
         daily  limitations  for BOD5,TSS,COD and oils and grease should
         not exceed the 30 day average  limitations  by  more  than  100
         percent.   The  maximum  30 day and daily limitations for pH and
         fecal coliforms are identical.

    2.   If a plant produced materials in more than one subcategory, for
         instance wool and synthetics, the effluent  limitations  should
         be  set  by  proration  on the basis of the percentage of fiber
         being processed to a product.
                                  161

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                               SECTION X

        EFFLUENT REDUCTION ATTAINABLE THROUGH THE APPLICATION OF
         THE BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE
                    EFFLUENT LIMITATIONS GUIDELINES

                              INTRODUCTION

The effluent limitations which must be achieved no later  than  July  1,
1983,  are  not  based  on  an average of the best performance within an
industrial category, but are determined by  identifying  the  very  best
control  and  treatment  technology  employed by a specific point source
within the industrial category and subcategory, or by one industry where
it is readily transferable to another.  A specific finding must be  made
as  to  the  availability of control measures and practices to eliminate
the discharge of pollutants,  taking  into  account  the  cost  of  such
elimination.

Consideration must also be given to:

    The age of the equipment and facilities involved;

    The process employed;

    The engineering aspects of the application of various types
    of control techniques;

    Process changes;

    The cost of achieving the effluent reduction resulting
    from application of the technology;

    Non-water quality environmental impact (including energy
    requirements).

Also,  Best  Available Technology Economically Achievable emphasizes in-
process controls as well as control or additional  treatment  techniques
employed at the end of the production process.

This  level  of  technology  considers those plant processes and control
technologies which, at the pilot plant, semi-works,  and  other  levels,
have demonstrated both technological performances and economic viability
at   a   level  sufficient  to  reasonably  justify  investing  in  such
facilities.  It is the highest degree of  control  technology  that  has
been  achieved  or has been demonstrated to be capable of being designed
for plant  scale  operation  up  to  and  including  "no  discharge"  of
pollutants.    Although   economic   factors   are  considered  in  this
development, of current technology, subject to  limitations  imposed  by
economic and engineering feasibility.
                                  162

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          EFFLUENT REDUCTION ATTAINABLE THROUGH APPLICATION OF
         THE BEST AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE

Based  on  the information contained in Section III through VIII of this
report, a determination has been  made  that  the  quality  of  effluent
attainable  through  the  application  of  the Best Available Technology
Economically Achievable is as listed in Table  33.   The  technology  to
achieve  these  goals  is  generally  available,  although  the advanced
treatment techniques may not have yet been  applied  at  full  scale  to
plants within each subcategory.

                       IDENTIFICATION OF THE BEST
              AVAILABLE TECHNOLOGY ECONOMICALLY ACHIEVABLE

Best  available  control  technology  economically  achievable  for  the
textile  manufacturing  industry  includes  the  preliminary  screening,
primary  settling  (wool scouring only) , coagulation (carpet mills only) ,
secondary biological treatment and chlorination listed  under  the  Best
Practicable  Control  Technology  Currently  Available.  In addition, it
includes advanced treatment techniques such  as  multi-media  filtration
and/or activated carbon adsorption following biological treatment.

Management  controls  over  housekeeping and water use practices will be
stricter than  required  for  1977.   However,  no  additional  in-plant
controls  will  be  required to achieve the specified levels of effluent
reduction.  There are several in-plant controls and  modifications  that
provide  alternatives  and  trade-offs to additional effluent treatment.
For example, a scouring bowl train designed for complete counter-current
operation  can  significantly  reduce  water  usage  at  wool   scouring
facilities.

The  stated  guidelines  for  July  1,  1983,  for  small  plants in six
subcategories (wool scouring, wool finishing,  woven  fabric  finishing,
knit  fabric  finishing  carpet  Mills  and  stock  and  yarn dyeing and
finishing) and both small and large  plants  in  subcategory  3   (greige
goods)  can be achieved by adding a multi-media filtration system to the
best practicable  control  technology.   This  advanced  technology  can
insure  that  operational  variability  is  minimized.   The recommended
effluent limitations are based on the effluent reduction attainable with
the  best  practicable  control  technology  without  an  allowance  for
operational variability.
                                  163

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                                    TABLE   33

                         MAXIMUM THIRTY DAY AVERAGE
                       RECOMMENDED EFFLUENT LIMITATION
                         GUIDELINES FOR JULY 1, 1983
                                           Effluent Limitations  (1)
                                    BODS
                                  kg/lOOOkg
Plant Subcategory                (Ib/lOOOlb)

1.  TOOL SCOURING (2)
    Plant capacity less than         2.5
     6,500 kg/day (14,300 Ih/day)
    Plant capacity greater than      2.5
     6,500 kg/day (14,300 Ib/day)

2.  WOOL FINISHING
    Plant capacity less than         5.0
     900 kg/day (1,980 Ib/day)
    Plant capacity greater than      5.0
     900 kg/day (1,980 Ib/day)

3.  GREIGE MILLS
    All plant sizes                  0.3

4.  WOVEN FABRIC FINISHING
    Plant capacity less than         1.5
     1,000 kg/day (2,200 Ib/day)
    Plant capacity greater than      1.5
     1,000 kg/day (2,200 Ib/day)

5.  KNIT FABRIC FINISHING
    Plant capacity less than         1.2
     3,450 kg/day (7,590 Ib/day)
    Plant capacity greater than      1.2
     3,450 kg/day (7,590 Ib/day)

6.  CARPET MILLS
    Plant capacity less than         2.9
     3,450 kg/day (7,590 Ib/day)
    Plant capacity greater than      2.9
     3,450 kg/day (7,590 Ib/day)

7.  STOCK AND YARN DYEING AND FINISH-
    ING
    Plant capacity less than         2.3
     3,100 kg/day (6,820 Ib/day)
    Plant capacity greater than      2.3
     3,100 kg/day (6,820 Ib/day)
    TSS
kg/lOOOkg
(Ib/lOOOlb)
    2.5

    2.5



    5.0

    5.0



    0.3


    4.6

    4.6



    5.3

    5.3



    2.9

    2.9




    6.1

    6.1
   COD
kg/lOOOkg
(Ib/lOOOlb)
   NA

   64



   NA

   14.9



   NA


   NA

     8.8



   MA

     6.4



   :MA

     8.0




   NA

   12.5
                               NA MEANS NOT APPLICABLE

(1)  Plant capacities and discharge limitations are stated for Subcategories
     1 and 2 per weight of raw wool received at the wool scouring or wool
     finishing operation and are stated for Subcategories 3, 4, 5, 6 and 7
     per weight of final material produced by the facility.

     For all Subcategories pH should range between 6.0 to 9.0 at any time.

     For all Subcategories Most Probable Number  (MPN) of Fecal Coliforms
     should not exceed 400 counts per 100 ml.

(2)  For all Wool Scouring plants  (Subcategory 1) Oils and Grease should
     not exceed 1.9 kg (lb)/1000 kg (Ib) grease wool.
                                      161*

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    The  guidelines  for  large  plants in six subcategories  (wool scouring,
    wool finishing, woven fabric finishing, knit  fabric  finishing,  carpet
    Mills and stock and yarn dyeing and finishing) can be achieved by adding
    an  activated  carbon  adsorption system to the best practicable control
    technology.  This advanced technology  has  been  shown  to  effectively
     (greater  than  90  percent)  remove  COD  from textile wastes.  In some
    plants where large quantities of dispersed dyes or materials  with  poor
    adsorptive  capacity are discharged, a multi-media filtration system may
    also be needed.  The recommended effluent limitations are based  on  the
    best  effluent  reduction  attainable  with the best practicable control
    technology and include an  additional  reduction  on  the  order  of  60
    percent of the remaining COD.
*
                      RATIONALE FOR THE SELECTION OF BEST
              AVAILABLE CONTROL TECHNOLOGY ECONOMICALLY ACHIEVABLE

    Age and Size of Equipment and Facilities

    The industry has generally modernized its plants as new methods that are
    economically  attractive  had  been introduced.  No relationship between
    age of production plant and effectiveness of its pollution  control  was
    found,  size was shown in section IV to require separate limitations for
    small  plants  because  of  severe  diseconomies  of scale.  significant
    differences in effluent limitations have resulted.

    Total Cost of Application in Relation to Effluent Reduction Benefits

    Based on information contained in  Section  VIII  of  this  report,  the
    estimated  increase  in final product costs required to achieve the best
    available effluent reductions range from 0.05 to 0.4 cents per  kilogram
     (0.1  to  0.8  cents  per  pound)  product  processed  by  all plants in
    subcategory 3 and by small plants in subcategories 1, 2,  4, 5, 6, and   7
    with  capacities  less  than  6,500  kg/day   (14,300 Ib/day), 900 kg/day
     (1,980  Ib/day),  1,000  kg/day   (2,250  Ib/day),  3,450  kg/day   (7,590
    Ib/day),  3,450  kg/day   (7,590 Ib/day), and 3,100 kg/day  (6,820 Ib/day)
    respectively.  For larger plants in the industry,  the  price  increases
    ranged  from  0.4  cents per kilogram  (0.8 cents per pound) to a high of
    2.0 cents per kilogram  (4.5  cents  per  pound).   The  estimated  costs
    required  to  achieve  best  practicable  and  best  available  effluent
    reductions range between 0.3 and  1.1 cents per  kilogram   (0.6  and  2.5
    cents  per  pound)  product  from  small plants and 0.5 to 2.5 cents per
    kilogram  (1.0 and 5.4 cents per pound) product from larger plants.

    Engineering Aspects of Control Technique Application

    The specified level of technology is achievable.   Biological  treatment
    is  practiced  throughout  the  textile  industry  and  activated carbon
    adsorbtion is practiced at four textile plants.  The  use  of  activated
    carbon  to  treat  textile wastes was pioneered at a Pennsylvania carpet
                                       165

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mill and at least one synthetic knit goods plant (mill  HH)  is installing
activated carbon.

Multi-media  filtration  has  been  used  effectively  in  various   EPA
applications  including  Lebanon,  Ohio,  and Washington,  B.C.   Filtration
is also used as pretreatment before  carbon  adsorption  at  a  Virginia
textile mill.

Process Changes

No  in-plant  changes  will  be needed by most plants to meet the limits
specified.  Some in-plant techniques are available  as   alternatives  to
effluent treatment techniques.

Non-Water Quality Environmental Impact

The  non-water  quality  environmental  impact will essentially be those
described in Section IX.  It is concluded that no  new  serious  impacts
will be introduced.

Factors to be Considered in Applying Level II Guidelines

    1.   Limitations  are  based  on  30   day   averages.     Based   on
         performances of biological waste treatment systems,  the maximum
         daily limitations for BOD5, TSS, COD and oils and grease should
         not  exceed  the  30  day  average limitations by more than 100
         percent.  The maximum 30 day and daily limitations for  pH  and
         fecal coliforms are identical.

    2.   If a plant produced materials in more than one subcategory  for
         instance  wool  and synthetics, the effluent limitations should
         be set by proration on the basis of  the  percentage  of  fiber
         being processed to a product.
                                  166

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                               SECTION XI

                    NEW SOURCE PERFORMANCE STANDARDS

                              INTRODUCTION

The effluent limitations that must be achieved by new sources are termed
performance  standards.   The  New Source Performance Standards apply to
any source for which construction starts after the  publication  of  the
proposed regulations for the Standards.  The Standards are determined by
adding  to  the  consideration underlying the identification of the Best
Practicable control Technology Currently Available, a  determination  of
what higher levels of pollution control are available through the use of
improved  production  processes  and/or  treatment techniques.  Thus, in
addition to considering the best  in-plant  and  end-of-process  control
technology, New source Performance Standards are based on an analysis of
the  process  itself.  Alternative processes, operating methods or other
alternatives are considered.  However, the end result of the analysis is
to  identify  effluent  standards  which  reflect  levels   of   control
achievable  through the use of improved production processes (as well as
control technology),  rather  than  prescribing  a  particular  type  of
process  or  technology which must be employed.  A further determination
made is whether a standard permitting  no  discharge  of  pollutants  is
practicable.

Consideration must also be given to:

    Operating methods;

    Batch, as opposed to continuous, operations;

    Use of alternative raw materials and mixes of raw materials;

    Use of dry rather than wet processes (including substitution
    of recoverable solvents for water) ;

    Recovery of pollutants as by-products.

             EFFLUENT REDUCTION ATTAINABLE FOR NEW SOURCES

The  effluent  limitation  guidelines  for  new sources are identical to
those for the Best Available Control Technology Economically  Achievable
(See  Section  X).   This  limitation is achievable in newly constructed
plants.  In-plant controls and waste treatment technology identified  in
Section X are available now and applicable to new plants.

The  new  source technology is the same as that identified in section X:
preliminary  screening,   primary   settling    (wool   scouring   only),
coagulation  (carpet  mills  only), biological treatment and multi-media
                                  168

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filtration and/or activated carbon adsorption.  The  conclusion  reached
in  section  X  with respect to Total Cost of Application in Relation to
Effluent  Reduction  Benefits,  the  Engineering  Aspects   of   Control
Technique  Application, Process Changes, Non-Water Quality Environmental
Impact and Factors to be Considered in  Applying  Level  II  Guidelines,
aPPly with equal force to those New Performance Standards.

                       FRETREATMENT REQUIREMENTS

Three  constituents  of  the  waste water from plants within the textile
industry have been found which would interfere with,  pass  through,  or
otherwise  be  incompatible  with  a well designed and operated publicly
ownad activated sludge or trickling filter waste water treatment  plant.
Waste  water  constituents include grease from wool scouring operations,
latex from carpet mills and heavy metals such as chromium used in  dyes.
Adequate  control  methods  can  and  should be used to keep significant
quantities of these materials out of the waste water.   Dye  substitutes
are available for many dyes containing heavy metals.
                                  169

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                               SECTION XII

                             ACKNOWLEDGMENTS
Special thanks and appreciation are due the following manufacturing
organizations:  The American Textile Manufacturers Institute; The
Northern Textile Association; The Carpet and Rug Institute; and
The American Association of Textile Chemists and Colorists.

Appreciation is expressed for the interest of several individuals
within the Environmental Protection Agency:  W.  H. Cloward, Region IV;
Thomas Sargent, SERL, Athens, Georgia; Edmund Struzeski, NFIC, Denver,
Colorado; Charles Ris, 0 R & D; William Hancuff, George Webster,
Ernst Hall, Allen Cywin, EGD.

Special thanks are due to Richard Sternberg for his advice, support
and guidance.  Thanks are also due the many secretaries who typed
and retyped this document:  Aqua McNeal, Pearl Smith, Chris Miller,
Vanessa Datcher, Karen Thompson, and Fran Hansborough.

Special acknowledgment is made of the contributions of industry
personnel who provided information to the study.  Their active response,
cooperation and assistance is greatly appreciated.
                                   170

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                              SECTION XIII

                               REFERENCES

A review of the recent literature for references on Textile wastes and
waste treatment has produced over 200 references.  Brief abstracts of
50 of these references are included as well as the full list of references,
 (2)   "The BOD of Textile Chemicals, Updated List -  1966"
      American Dyestuff Reporter,  (55) No.  18, 39-42,  1966.

     (s elf-explanat ory)

 (15)  "What the Mills are Doing to Control  Water Pollution"
    Textile Chemist and colorist,  (1) No. 6, 25-36,  1969.

    This article gives a brief rundown of waste control activities  at:

    1.  American Enka, N.C. facility, where rayon, nylon, and
        polyester are produced

    2.  Burlington Industries  (general)

    3.  Cannon Mills  (discussed new  design  in detail)

    4.  Cone Mills (general)

    5.  Dan River Mills  (Danville  plant)

    6.  M. Lowenstein & sons  (Lyman  Printing and Finishing Co.)

 (18)     Molvar, A., C. Rodman, and  E. Shunney
    "Treating Textile Wastes with  Activated Carbon"

    Discusses activated carbon treatment in general,  pilot plant
    work, and actual operating data  for a full size  waste treatment
    system.  The mill's identity is  nor given  (dyeing and finishing).

 (21)     Souther, R.H.
    "Waste Treatment Studies at duett, Peabody 6 Company Finishing Plant"
    American Dyestuff Reporter,  (58) No.  15,  13-16,  1969.

    Detailed operating data on the Arrow Co., Division at Waterford,  New
    York.  The treatment system consists of an "extended-contact,
    activated sludge step, bio-aeration process."  Also includes caustic
    recovery.
                                   172

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(22)      "Wastewater Treatment Recycles 80 Percent of Industrial Flow"
    American Textile Reporter, (83)  No. 51, 14-15, 1969.

    Very brief  description and general flow diagram of the waste treat-
    ment system using activated carbon at Hollytex Carpet Mills (near
    Philadelphia).   No real operating data is given.
(25)      Jones, E.L., T.A. Alspaugh, and H.B. Stokes

    "Aerobic Treatment of Textile Mill Waste"
    JWPCF (34)  No.  5, 495-512, 1962.

    Cone Mills, joint treatment of mill and municipal sewage by
    contact stabilization process.  (Pilot plant operating data.)

(47)      Poon,  C.P.C.
    "Biodegradability and Treatability of Combined Nylon and
    Municipal Wastes"
    JWPCF (42)  No.  1, 100-105, 1970.

    Treatability study of wastes taken from the Belding Chemical Co.
    in Thomaston,  Connecticut.  Strictly a laboratory study.

(49)      Kwie,  W.W.
    "Ozone Treats  Wastestreams from Polymer Plant"
    Water and sewage Works, 116, 74-78, 1969.

    Laboratory  study on ozone treatment of wastes from polymer plant
    (including  SANS).  The study did not produce very satisfying results.

(52)      Wheatland,  A.B.
    "Activated  Sludge Treatment of some Organic Wastes"
    Proc. 22nd  Ind.  Waste Conf. Purdue Univ.  983-1008, 1967.

    Treatability study on a simulated synthetic fiber production and
    dyeing waste using a bench scale activated sludge unit.

(53)      Carrigue,  C.S., and L.U. Jauregui
    "Sodium Hydroxide Recovery in the Textile industry"
    Proc. 22nd  Ind.  Waste Conf. Purdue Univ., 1966.

    Castelar Textile Mill, Argentina (cotton goods)
    Description of  NaOH recovery from the mercerizing process.  NaOH
    is filtered and then concentrated by evaporating.  Design criteria,
    operating data  and capital and operating costs are given.

(56)      Taylor, E.F., G.C. Gross, and R.F. Rocheleau
    "Biochemical Oxidation of Wastes from the New Plant for Manufacturing
    Orion at Waynesboro, Va."
                                  173

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    Proc.  15th  Ind.  Waste Conf.  Purdue Univ.,  1961.

    Detailed description of  Dupont's  Waynesboro works.   Wciste facilities
    consist  of  a catalytic oxidation  unit which completely oxidizes the
    organics associated with the recovery of  dimethylformamide and an
    activated sludge unit for treatment of dilute organic materials such
    as  acrylonitrile, dimethylformamide and formic acid.

(57)      Sadow,  R.D.
    "The  Treatment of Zefran Fiber Wastes" (acrylic fiber)

    Dow Chemical Company's Williamsburg, Va.,  plant.   Description of
    waste treatment process  which includes primary settling, chemical
    coagulation, a Dowpac oxidation tower, and secondary settling.
    Operating data and design criteria are given.

(61)      Jones,  L.L.
    "Textile Waste Treatment at  Canton Cotton Mills"
    JWPCF (37)  No. 12, 1693-1695, 1965.

    Gives a  rather brief description  of their activated sludge unit with
    design criteria, operating data (sketchy)  and cost information.

(62)   Smith, A.L.
    "Waste Disposal by Textile Plants"
    JWPCF (37)  No. 11, 1607-13,  1965.

    Very  general article, gives  some  synthetic textile waste characteris-
    tics  and very brief descriptions  of waste characteristics and treat-
    ment  methods at:

    1.  Chatham Manufacturing Co., Elkin, N.C. (multi-fiber woolen mill)
    2.  J.P. Stevens Co., Wallace Plant

(63)      Dean,  B.T.
    "Nylon Waste Treatment"
    JWPCF (33)  No. 8, 864-70, 1961.

    Operating experience of  the  Chemstrand Corp.  Pensacola plant which
    utilizes an activated sluge  unit  followed by a post-treatment lagoon,

(76)      Suchecki, S.M.
    "A Dyer's "Operation Cleanup"
    Textile  Industries  (130) No. 6, 113, 1966.

    Description of Northern  Dyeing Co., Washington, N.J. treatment
    facilities.   Very little operating data given.

(86)      Souther, G.P.
                                  174

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    "Textile  Water  Pollution woes  Can be Resolved by Solvents"
    American  Textile Reporter (54)  No.  9, 11,  13, 1970.

    Describes solvent sizing and dyeing processes.   This is an  infor-
    mative  but not  very detailed article.

(95)      Porter,  J.J.
    "Concepts for Carbon Adsorption in Waste Treatment"
    Textile Chemists and Colorists (4)  No.  2,  29-35, 1972.

    The  history of  carbon's entry  into the waste treatment  field is
    presented.   Interpretations of teh fundamental kinetics and
    thermodynamics  of carbon adsoption are also given with  several
    specific  examples cited.

(99)      Rodman,  C.A.
    "Removal  of Color from Textile Dye Wastes"
    Textile Chemists and Colorists (3)  No.  11, 239-47,  1971.

    Solutions of four types of dyestuffs were  treated by several methods
    that have been  used practically or experimentally for color removal.
    Among these were coagulation by lime and by alum; extended  aeration,
    activated carbon adsorption, reverse osmosis, and treatment with high
    pressure  oxygen and cobalt-60  radiation.

(100)  Rhame,  G.A.
    "Aeration Treatment of Textile Finishing Wastes in South Carolina"
    American  Dyestuff Reporter  (60)  No. 11, 46, 1971.

    Operating data  of several unidentified plants is presented  along
    with general design criteria.

(103)  Porter, J.J.
    "Treatment of Textile Waste with Activated Carbon"
    American  Dyestuff Reporter  (61)  No. 8,  24-7, 1972.

    Considerations  in evaluating the potential application of carbon
    adsorption to a waste stream are discussed along with procedures
    for  conducting  laboratory studies.

(106)     Stone, R.
    "Carpet Mill Industrial Waste  System"
    JWPCF (44)  No.  3,  470-478, 1972.

    A description of the waste treatment system of the Walter Carpet
    Mill, City of Industry, California is presented.

(108)  Little, A.H.
    "Use and  Conservation of Water in Textile  Processing"
                                  175

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    Journal  of the  Society of  Dyers  and  Colorists  (87)  No.  5,  137-45,  1971.

    Investigation of  water usages  in unit  processes  under normal pro-
    duction  conditions.   The effects of  different  dyeing  and bleaching
    processes have  been  studied.   Possible methods of  conservation of
    water are discussed,  including Contra-flow washing.   In addition,
    the effects  of  changes in  processing,  the  size,  type  and speed of
    machines and the  effects of  cloth weight and batch size are discussed.

(110)  Masseli, J.W.,  N.W. Massell, and M.C. Burford
    "Factors Affecting Textile Waste Treatability"
    Textile  industries for October 1971, p. 84-117

    General  design  parameters  of activated sludge  waste treatment are
    discussed along with startup and operational considerations.  Waste
    contributions  (in terms of % total BOD), are given  for the individual
    process  chemicals used in  a  typical  cotton mill, cotton/synthetic
    mill, and woolen  mill.

(Ill)  Shunney, E.L.,  Perratti, A.E., and Rodman, C.A.
    "Decolorization of Carpet  Yarn Dye Wastewater"
    American Dyestuff Reporter (60)  No.  6, 32-40,  1971.

    Laboratory and  full-scale  operation  of bio-regenerated  activated
    carbon  treatment  of  carpet yarn  fiber  dyeing are discussed.  The
    facility described is the  C. H.  Masland &  Sons plant  in Wakefield,
    Rhode  Island.

(113)  Rodman, C.A., and  E. L.  Shunney
    "A New  concept  for the Biological Treatment of Textile  Finishing
    Wastes"
    Chem.  Eng. Progr. Symp. ser. 67, 107,  451-457, 1971.

    (Same  subject  as  ref. Ill)

(115)  Rodman, C.A.  and E. L. Shunney
    "Novel  Approach Removes color  from Textile Dyeing  Wastes"
    Water  and Waste Eng. (8) No. 9,  #18-23,  1971.

    (Same  subject  as  ref. Ill)

(118)  "Bio-regenerated Activated Carbon  Treatment  of Textile Dye Wastewate
    Water  Pollution Control Research Series  1209  OD  WW 01/71.

    (Same  subject  as  ref. Ill)

(122)  Powell,  S.D.
    "Biodegradation of Authraquinone Disperse Dyes"
    Thesis,  Georgia Inst. Tech., 9,  238, 1971,'
                                  176

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    Three  authraquincne  disperse  dyes,  Disperse  Violet  1  (C.I.  61100),
    Disperse  Blue  3  (C.I.  61505),  and Disperse Blue  7  (C.I.  62500),
    were partially metabolized  by bacteria  normally  present  in  domestic
    activated sludge.  Disperse Red  15  (C.I.  60710), was  left unchanged
    by the sludge.   The  nature  of the metabolites  produced showed that
    the dyes  had not actually been degraded,  but merely converted to
    derivatives of the original dyes.

(123) Hood, W.S.
    "Color Evaluation in Effluents from Textile  Dyeing  and Finishing
    Processes"

    Initial concentration and rates  of  degradation of dyes and  chemicals
    in textile effluents were studied.   Field studies were made to
    observe conditions and to collect samples of water  from  streams in
    the Coosa River  Basin.   The samples were  analyzed for content of
    specific  dye auxiliaries and  color.  Color degradation was  achieved
    under  simulated  stream conditions,  both in textile  effluents and  in
    river  samples.

(124) Soria,  J.R.R.
    "Biodegradability of Some Dye Carriers"
    Thesis, Georgia  Inst.  Tech.,  9,  238, 1971.

    Carriers  covered in  this study were resistant  to degradation in
    conventional activated sludge waste disposal plants.   Where bacteria
    were acclimated  to the chemicals and treatment times  were extended,
    degradation did  occur.

(125) Arnold, L.G.
    "Forecasting Quantity of Dyestuffs  and  Auxiliary Chemicals  Dis-
    charged into Georgia Streams  by  the Textile  Industry"
    Thesis, Georgia  Inst.  Tech.,  9,  238, 1971.

    The quantity and concentration of the major  textile wet-processing
    chemicals in effluents are  reported.

(126) Pratt,  H.D., Jr.
    "A Study  of the  Degradation of Some Azo Disperse Dyes in Waste
    Disposal  Systems"
    Thesis, Georgia  Inst.  Tech.,  9,  238, 1971.

    Two azo disperse dyes,  Disperse  Orange  5  (C.I. 11100)  and Disperse
    Red 5  (C.I. 11215),  were degraded by the  bacteria in  conventional
    waste  treatment  facilities  into  aromatic  amines.  Biological de-
    gradation produced identical  metabolites  as  those formed by chemi-
    cal reduction.
                                  177

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(127)  Anderson,  J.H.
    11 Biodegraelation of  Vinyl  Sulfone Reactive Dyes"
    Thesis,  Georgia Inst.  Tech.,  9  238,  1971.

    Biodegradation  of three vinyl sulfone reactive dyes,  Reactive
    Blue  19, Reactive Violet  5, and Reactive  Black 5,  were investigated
    under laboratory conditions simulating those  employed in conventional
    activated  sludge plants.   The study  failed to show any evidence of
    degradation.   Reactive Blue 19, and  Reactive  Violet 5 showed evidence
    of degradation  under anaerobic  conditions.

(141)  "The Centrifugal  Recovery of  Wool  Grease"
    Wool  Science Review  #37,  p.  23-36,  1969.

    This  very  detailed  article discussed the  composition  of wool scour
    liquor,  general principles of recovery, detailed operating charac-
    teristics  of centrifuges,  and the economics of wool grease recovery.

(143)  Harker,  R.P., and E.M.  Rock
    "Water conservation and Effluent Disposal in  the Wool Textile Industry
    J. Soc.  Dyers and Colourists  (87), No.  12, 481-3,  1971.

    Discusses  the wool  textile industry  in the U.K.   Givess water con-
    sumption for various unit processes  in terms  of  gal/lb product.
    This  article also gives typical wool processing  effluents and a
    description  of  the  Traflo-W process  which entails ch€;mical coagu-
    lation followed by  vacuum filtration.  BOD is reduced by 80%.

(149)  Rea, J.E.
    "Treatment of Carpet Wastes for Disposal"
    Proc. industrial Waste and Pollution conference  and Advanced
    Water conference, 22nd and 3rd.  Oklahoma State  University,
    Stillwater,  Oklahoma,  March 24-30,  1971.

    This  paper identifies design  criteria and operating data for the
    waste treatment facilities at Sequoyah Mills  in  Anadarko, Okla.
    The waste  treatment facilities  consist of an  aerated  lagoon and
    stabilization pond.  Pilot work is included which shows the re-
    lationship of BOD removal to  aeration time.

(150)  Paulson, Per
    "Water Purification - An  Alternative to Solvent  Dyeing"
    International Dyer  & Textile  Printer - June 4, 1971.

    A  brief description of a  new  waste treatment  process  employing
    sedimentation followed by ion exchange.  Pilot plant  work on
    dyeing liquor showed COD  removals greater than 90%.

(161)  Kulkarni,  H.R., S.U. Khan,  and Deshpande
                                  178

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    "Characterization of Textile Wastes  and Recovery of Caustic Soda
    from Kier Wastes"
    Environmental Health  (13) No.  2,  120-127,  1971.

    A case study of  "A  Typical cotton Textile  Industry" is  presented
    in the paper with reference to economical  method of treatment of
    the waste waters and recovery  of  caustic soda during the  process
    of treatment.  Ninety-eight percent  caustic  recovery has  been
    accomplished using  dialysis.

(162) "Biodegradation of "Elvanol" -  A Report  from Du  Pont"

    The report  concludes that domestic and textile mill activated
    sludge microorganisms  can acclimate  to "Elvanol" T-25 under con-
    ditions  attainable  in  conventional waste treatment systems and
    that removals of over  90% can  be  achieved  if the organisms are
    properly acclimated.

(164) Ryder, L.W.
    "The Design and  construction of the  Treatment Plant for Wool
    Scouring and Dyeing Wastes at  Manufacturing  Plant, Glasgow, Va."
    J. Boston Soc. Civil Engrs., 37,  183-203,  April  1950.

    This article gives  a very detailed description and design basis
    for the  waste treatment  system consisting  of equalization, acid-
    flocculation, and neutralization. The plant achieves a BOD re-
    moval of 60%, SS removal of  96% and  a grease removal of 97%.

(168) Rodman, C.A. ,  and E.L. Shunney
    "Clean Clear Effluent"
    Tex. Manufacturer  (99) No. 49, 53-56, 1972.

    A description of the Fram Corporation bio-regenerated carbon
    adsorption  process  is  given  along with laboratory  and pilot plant
    operating data.  The pilot plant  treated waste water from the
    carpet yarn fibre dyeing plant of C.H. Masland & Sons,  Wakefield,
    Rhode Island.  A COD reduction of 81% and  a  color  reduction of
    99.436 is reported.

(175) Wilroy, R.D.
    "Industrial Wastes  from  Scouring  Rug Wools and the Removal of
    Dieldrin"
    Proc.  18th  Ind.  Waste  conf., Purdue  Univ., April 30, May  1-2,  1963,

    The article describes  design considerations  and  operating exper-
    ience of a  waste treatment system consisting of  fine screens,
    sedimentation basin,  and an  anaerobic lagoon.  A BOD reduction
    of between  80 and  9038  and a  Dieldrin reduction of  99% is  claimed
    for the  system.
                                  179

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(181)  Stewart,  R.G.
    "Pollution  and the  Wool  Industry"
    Wool Research Organization  of  New  Zealand,  Report No.  10,  1971.

    This article is  a rather general outline  of the  sources  of wool
    processing  wastes and the present  waste treatment technology
    available.

(190)  Rebhu.n, M., A. Weinberg,  and N.  Narkis
    "Treatment  of Wastewater from  Cotton  Dyeing and  Finishing  Works
    for Reuse"
    Eng. Bull.  Purdue Univ., Eng.  Ext.  137  (pt. 2),  1970.

    This article describes the  results of pilot plant work on  the
    waste  from  a cotton dyeing  and finishing  mill in Israel.   Alum
    flocculation followed by filtration was shown to produce a 95%
    color  reduction  and a 61% COD  reduction.  Activated carbon was
    shown  to be a poor  sorbent,  and greater success  was achieved
    using  a  weak base ion exchange resins.

(202)  Alspaugh, T.A.
    "Treating Dye Wastewaters"
    45th Annual Conference of tne  Water Pollution Control  Federation
    Atlanta, Georgia, Oct. 8-13,  1972.

    Alspaugh gives a very thorough evaluation of presently employed
    and promising future waste  treatment  unit operations.   Experienced
    removal  efficiencies and general treatment  costs are also  given.
    A summary of current waste  treatment  research is given.

(213)  Corning,  V.
    "Pollution  Control  in Jantzen  Dyehouse"
    Knitting Times  (39)  No.  35,  44-45, 1970.

    Brief  description of Portland, Oregon plant, little detail.

(214)  "Textile  Water Pollution  cleanup Picks  Up Speed"
    Textile  World,  54-66, November 1967.

    Fairly general arcicle but  does give  some operating data and waste
    treatment descriptions for  several plants:

    1. J.P. Stevens &  Co.,  Wallace,  N.C. plant

    2. UPD's Bluefield, Va., plant

    3. Burlington's Cooleemee, N.C.
                                  180

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    4.   Lyman  Printing and Finishing Co.,  Lyman,  N.C.

    5.   J.  P.  Stevens 6 Co.,  Utica-Mohawk  plant

(215)  Sahlie,  R.S.,  and C.E.  Steinmetz
    "Pilot  Wastewater Study Gives Encouraging Indications"
    Modern  Textiles,  (50)  No.  11, 20-28,  1969.

    Description of pilot plant work at fiber Industries,  Shelby, N.C.
    plant.  Article  is not very detailed.

(216)     "Trade Effluent Control in the Carpet Industry"
    Textile Institute and Industry, (3)  No.  9,  237-40,  1965.

    General discussion, gives values for typical  effluents.
                                  181

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                                  183

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29. Kwie,  W.W.,  "Ozone Treats Wastestreams From Polymer Plant," Water
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40. Environmental Protection Agency—contract  12090 DWM, Masland and Sons-
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41  Ibid—Contract C  12090 ESG, American Enka  "Hydroxide Precipitation
    and Recovery of Certain Metallic Ions from Waste Waters."

42.  Ibid—Contract C 12090 GOX, Fiber Industries, "Reuse of  Chemical  Fibe
    Plant Wastewater and Cooling Water Slowdown."

43. Ibid—contract 12090 EGW, Holliston Mills, "Treatment of  Cotton  Texti."
    Wastes by Enzymes and Unique High Rate Trickling Filter System."
                                   184

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44. Ibid—Contract 12090 EQO, "Palisades Industries," Demonstration of a
    New Process for the Treatment of High Concentration Textile Dyeing
    and Finishing Wastes."

45. Ibid—contract 12090 FWD, American Association of Textile Chemists
    and Colorists, "The use of oxygen and ionizing radiation to decolorize
    dye wastes."

46. Ibid—Contract 12090 EOE, North Carolina State University, "The
    Feasibility of Precipitation Removal of Synthetic Sizing Materials
    from Textile Wastewaters."

47. Poon, E.P.C., "Biodegradability and Treatability of Combined Nylon and
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50. Michelsen, D.L., "Treatment of Dye Wastes," Textile Chem. Colorist,
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51. Bode, H.E., "Process for sizing textiles and the disposition of sizing
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52. Wheatland, A.B., "Activated Sludge Treatment of Some Organic Wastes,"
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53. Carrigue, C.S., L.U. Jaurequi, "Sodium hydroxide recovery in textile
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54. Reich, J.S., "Financial Return from Industrial Waste Pretreatment,"
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55. Neas, G., "Treatment of Viscose Rayon Wastes," Proc. 14th Ind. Waste
    Conference, Purdue University, Ext. Ser. 104, 450,  1960.

56. Taylor, E.F., G.C. Gross, C.E. Jones, and R.F. Rocheleau, "Biochemical
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57. sadow, R.D., "The Treatment of zefran Fiber Wastes," Proc. 15th Ind.
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                                  185

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58.  Hann, R.w. Jr., F.D. Callcott, "A Comprehensive Survey of Industrial
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59.  Alspaugh, T.A., "More Progress Needed in Water Pollution Control,"
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60.  chipperfield, P.N.J., "Performances of Plastic Filter Media in
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61.  Jones, L.J. Jr., "Textile Waste Treatment at Canton Cotton Mills,"
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62.  Smith, A.L., "Waste Disposal by Textile Plants," J. Water Pollutinon
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63.  Dean, B.T., "Nylon waste Treatment," J. Water Pollution Control Fed.,
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64.  "Aerated Lagoon Handles Ten Million Gallons per Day," Textile World,
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65.  English, W.I., T.A. Alspaugh, "Research Urgent on Water Purification,
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66.  "Water Pollution; Problems and Controls in Industry," Heating, Piping
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67.  Huddleston, R.L., "Biodegradable Detergents for the Textile Industry,"
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68.   Masselli, J., et al., "Simplifying Pollution Surveys in Textile Mills
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                                   186

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73. Wilroy, R.D., "Feasibility of Treating Textile Wastes in connection
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82. Little, A.H., "Treatment of Textile Waste Liquors," J. of  the Society
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                                   187

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                                  189

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115.     Rodman, c.A. , and E.L. shunney, "Novel approach removes colour from
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118.     Rodman, C.A., and E.L. Shunney  (Fram Corporation) , "Bio-Regenerated
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119.     Riggs, J.L., Adsorption/Filtration: A New Unit Process for the Trea-
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120.     Suchecki, S.M., "Biological Decomposition is Not Enough," Textile
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121.     "Pollution Control: Plant  Design is the Payoff," (Staff Interview
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122.     Powell, S.D., "Biodegradation of Anthraquinone Disperse Dyes,"
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123.     Hood, W.S., "Color Evaluation in Effluents from Textile Dyeing and
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124.     Soria, J.R.R.,  "Biodegradability of Some Dye Carriers," Master's
    Thesis, Georgia Inst. of Technology, March  1970.

125.     Arnold, L.G., "Forecasting Quantity of Dyestuffs and Auxiliary
    Chemicals Discharged into Georgia streams by the Textile Industry,"
    Master's Thesis, Georgia Inst.  of Technology, September 1967.

126.     Pratt, H.D. Jr., "A Study  of the Degradation of Some Azo Disperse
    Dyes in Waste Disposal Systems," Master's Thesis, Georgia Inst. of
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127.     Anderson, J.H., Biodegradation of Vinyl Sulfone Reactive Dyes,"
    Master's Thesis, Georgia Inst.  of Technology, December  1969.

128.     Porter, J.J., "How Should  we Treat our Changing Textile Waste Stre;
    Clemson University,  Rev. of Ind. Mgmt. 6 Textile Science,  10, 61-70,
    1971.
                                   190

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129.      Porter, J.J., "Pilot Studies With Activated Carbon," Paper Presented
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130.      Brandon, C.A., J. S.  Johnson, R.E. Minturn, and J.J. Porter, "Complete
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131.      Ameen, J.S., "Lint Elimination Enhances Textile Waste Treatment,"
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132.      Williamson, R., "Handling Dye Wastes in A Municipal Plant," Pub.
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133.   Craft, T.F., and G.G. Eichholz, "Synergistic treatment of textile
    dye wastes by irradiation and oxidation," Int. J. Appl. Radiar
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134.      Yulish, J., "Textile Industry Tackles its Waste Problems," Chemical
    Engineering,  (78), No. 11, 84, May 17, 1971.

135.      Rhame, G.A., "Liberty, S.C., Textile finishing waste," Wat. Wastes
    Enginaering,  (7) No. 5, C6, 1970.

136.      Phipps, W.H., "Activated carbon reclaims water for carpet mill,"
    Wat. Wastes Engineering,   (7)  No. 5, C22-C23, 1970.

137.      Driesen, M. , "Application of the Thermal Process Technique to
      Effluent Problems," Brit. Chem. Eng. (15) No. 9, 1154, 1970; Textile
    Tech. Digest, 28, 2687, 1971.

138.      Dixit, M.D., and D.V. Parikh, "Practical considerations in the reuse
    of water in the textile industry," Textile Dyer and Printer  (India),
    4, 45-50, June  1971.

139.      Kulkarni, H.R., S.U. Khan, and W.M. Deshpande, "Characterization of
    Textile Wastes and Recovery Caustic Soda from Kier Wastes," Colourage,
    (18) No. 13, 30-3, July 1, 1971.

140.      Porter, J.J., "The removal and fate of color in the textile waste
    stream," sources and Resources, 5, 23-4, 1972.

141.      "Centrifugal recovery of wool grease," Wool Science Review, 37,
    23-36, October  1969.
                                  191

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142.      Poon,  C.P.C., and E.L.  Shunney, "Demonstration of a New Process for
    the Treatment of High Concentration Textile Dyeing and Finishing
    Wastes," AATCC Symposium, March 31 - April 1, 1971.

143.      Barker,  R.P., and B.M.  Rock, "Water Conservation and Effluent Dispose
    in the Wool Textile Industry," J. Soc.  Dyers and Colourists,  (87),
    No.  12,  481-3, 1971.

144.      "Water Cleanup Costs, Cannon $6-million," Textile World,  (122) No. 1
    61,  63,  65, 1972.

145.      Lowndes, M.R., "Ozone for Water and Effluent Treatment," Chemistry
    and Industry, August 21, 1971.

146.      "Bug Husbandry is the Secret of Waste Disposal Plant Success,"
    Process  Engineering, 67-8, March 1971.

147.      Schaafhausen, J., "Measures of Hoechst A.G. Dye Works for the Treatm
    of Wastewaters," Stadtehygiene, 21, 61-2, 1970.  (German)

148.      Harmsen, H., "The New Biological Treatment Plant for the Works of
    Hoechst  at Kesterbach," Stadtehygiene,  21, 62-4, 1970.

149.      Rea, J.E. Jr., "Treatment of Carpet Wastes for Disposal," Proc.
    Industrial Waste and Pollution Control Conference and Advanced Water
    Conference, 22nd and 3rd., Oklahoma State University, Stillwater,
    Okla., March 24-30, 1971.

150.      Paulson, P., "Water Purification - An Alternative to Solvent  Dyeing,
    International Dyer & Textile Printer, June 4, 1971.

151.      Rizzo, J.L., "Granular Carbon for Wastewater Treatment," Water 6
    Sewage Works, (118) No. 8, 238-40, 1971.

152.      "Textile Mills Perfect Remedy for Dirtiest Problem:  Pollution,"
    America's Textile Reporter,  (84) No. 15,  18-19,  24-5, 30,  1970.

153.      "Achieving Pollution Control in Textiles:  A Report," America's Tex
    Reporter,  (84) No. 22, 20-23, 26, 27, 1970.

154.      work, R.W.,  "Research at the School of Textiles,"  North  Carolina  St
    University, Raleigh, North Carolina, 1971.

155.      Kollar, I.,  "Recovery of Zinc Ions  from Waste Solutions  in  the
    Processing of Viscose on Ion Exchanger," Czech  Patent,  (136)  No.  147,
     (Cl. D olc) , April  15,  1970.

156.     Khare, G.K. , and C.A. Sastry,  "Studies on  Characterization  and
                                   192

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    Pollutional Effects of Viscose Rayon Wastes," Environmental Health,
    Vol.  12,  99-109,  1970.

157.     Garrison, A.W., "The Effect of High Pressure Radiolysis on Textile
    Wastes,  Including Dyes and Dieldrin," Proc. 5th International Conf.
    Water Pollution Research, 1970.

158.     Sinev, O.P., "Decomposition of Cellulose Xanthate and Precipitation
    of Hydrocellulose During Purification of Waste Waters from Viscose
    Manufacture, Fibre Chem., No. 2, 180-3, March - April, 1969.

159.     Sinev, O.P., "Removal of Carbon Disulphide and Sulphur Compounds
    from Viscose Fibre Plant Effluent by Aeration, " Fibre Chem., No. 4,
    436-8, July - August, 1969.

160.     Marinich, V., et al., "Removal of Lubricants from Effluents of
    Caprolectan Production," Fibre Chem., No. 4, 459-61, July - Aug. 1969.

161.     Kulkarni, H.R., S.U. Khan, and W.M. Deshpande, "Characterization of
    Textile Wastes and Recovery of Caustic Soda from Kier Wastes," En-
    vironmental Health,  (13) No. 2, 120-27, 1971.


162.     "Biodegradation of "Elvanol" Polyvinyl Alcohol," Du Pont Company,
    Plastics Department, Wilmington, Delaware.

163.     Brandon, C.A., "Dynamic-Membrane Hyperfiltration-- Key to Reuse of
    Textile Dye Waste?" ASME Publication, 71-Tex-4.

164.     Ryder, L.W., "The Design and Construction of the Treatment Plant for
    Wool Scouring and Dyeing Wastes at Manufacturing Plant, Glasgow,
    Virginia," J. Boston Soc. Civil Engrs., 37, 183-203, April  1950.

165.     Bogren, G.G., "A Plant for the Degreasing of Wool Scouring Wastes,"
    J. Boston Soc. Civil Engrs,  (13) No. 1, 18-23, 1926.

166.     Masselli, J.W., and M.J. Buford, "Pollution Sources in Wool Scouring
    and Finishing Mills and their Reduction Through Process and Process
    Chemical Changes," Prepared for New England Interstate Water Pollution
    Control Commission.

167.     Laude, L. , "Economy and Recycling of Water in the Bleaching and
    Dyeing Industries," Centre Textile Ccntrole Sci. Bulletin, No. 78,
    481-99, June 1971.

168.     Rodman, C.A., and E.L. Shunney, "Clean Clear Effluent," Textile
    Manufacturer, (99) No. 49, 53-6, A.

169.     Barker, R.P., "Effluents from the wool Textile Industry - Problems
                                  193

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    Associated with Treatment'and Reuse," Chem. Eng. CE 8-13, Jan./Feb.
    1970.  (London)

170.      Little,  A.H., "The Treatment and Control of Bleaching and Dyeing
    Wastes," Water Pollution Control, London, 68, 178-89, 1969.

171.      Fathmann, D.H., "Solving the Effluent Problem in Textile Mills. I,"
    Tex.  (Neth.),  (29) No.  12,  918-20, 1970.

172.      Fathmann, D.H., "Solving the Effluent Problem in Textile Mills. II,
    Tex.  (Neth.),  (30) No.  1, 37-40, 1971.

173.      Laurie,  D.T., and C.A. Willis, "Treatment Studies of Combined Texti
    and Domestic Wastes."

174.      Buswell, A.M., and H.F. Mueller, "Treatment of Wool Wastes," Proc.
    llth Ind. Waste Conference, Purdue University, May 15-17, 1956.

175.      Wilroy,  R.D., "Industrial wastes from scouring Rug Wools and the
    Removal  of Dieldrin," Proc. 18th Ind. Waste Conf., Purdue University,
    April 30, May 1-2, 1963.

176.      Snyder,  D.W., "Dow Surfpac Pilot Study on Textile Waste," Proc. 18-
    Ind.  Waste Conference,  Purdue University, April 30, May 1-2,  1963.

177.      Stack, V.T., "Biological Treatment of Textile Wastes," Proc. 16th
    Ind.  Waste conference,  Purdue University, May 2-4, 1961.

178.      Williams, S.W., and G.A. Hutto, "Treatment of Textile Mill Wastes
    in Aerated Lagoons," Proc.  16th Ind. Waste Conf., Purdue University,
    May 2-4, 1961.

179.      Gramley, D.L., and M.S. Heath, "A Study of Water Pollution Control
    in the Textile Industry of North Carolina," Water Resources Research
    Institute of University of North Carolina.

180.      Perera,  N.A.P., "Textile Effluents and their Safe Disposal," Silk
    and Rayon Industries of India, 12, 555-74, November 1969.

181.      Stewart, R.G., "Pollution and the Wool Industry," Wool Research
    Organization of N.Z., Report No. 10, 1971.

182.      Ganapat, S.V., "Some Observations on In-Plant Process Control for
    Abatement of Pollution Load of Textile Wastes," Environmental Health,
    (8) No.  3, 169-173, 1966.

183.      veldsman, D.P., "Pollution Resulting from Textile Wastes," Wool
    Grower,   (23)  No.  5, 27, 29, 1970.
                                  194

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184.      Judkins, J.F., R.H. Binius, et al., "Gamma Radiation of Textile
    Wastewater to Reduce Pollution," Water Resources Research Inst.,
    Auborn,  University, Alabama.

185.      Howard, M., "Textiles:  Special Problems?" water and Wastes Engineerin
    March, 1973.

186.      Poon, C.P.C., and E.L. shunney, "Have a Space Problem," Water and
    Wastes Engineering, March 1973.

187.      "Pollutants are all burned Up," Water and Wastes Engineering,
    March 1973.

188.      "Clemson has wastewater Breakthrough," Southern Textile News, 12,
    October 18,  1971.

189.      "Waste Treatment System at Foremost Recycles Hundred Percent of Water,
    Mill Whistle, (29) No. 6, 2-3, 6, September 21, 1970.

190.      Rebhun, M., A. Weinberg, and N. Narkis, "Treatment of Wastewater from
    Cotton Dyeing and Finishing Works for Reuse."

191.      Petru, I.A., "Combined Treatment of Wool Scouring Wastes," J. Inst.
    Sew. Purif., Paper No. 3, 497-9, 1964.

192.      Kaukare, V.S., "Water Conservation and its Reuse from Treated
    Effluents," Textile Dyer and Printer  (Ind.)  (3) No. 1, 171-5,  1969.

193.      "Treatment System Allows  100 Percent Recycling of Wastewater,"
    Industrial Waste,  (19) No. 2, IW/18-19, March/April, 1973.

194.      Ingols, R.S., R. Roberts Jr., and E. Garper, and P. Vira, "A Study
    Of Sludge Digestion with Sodium Chloride and Sulfate," PB196732,
    Final Report Project No. B 338, under Res. Grant RG 17070, Fed. Water
    Quality Admin., Dept. Interior, by Ga. Inst. Tech. Eng. Expt.  Sta.,
    Atlanta, Ga., September  1970.

195.      Rayburn, J.A., "Examine Those Effluents," American Dyestuff Reporter,
     (61) No. 9,  103-4, 1972.

196.      Case, F.N., E.E. Ketchen, and T.A. Alspaugh, "Gamma-Induced Low
    Temperature Oxidation of Textile Effluents," JAATCC, (5) No. 9, 1973.

197.      Natha, Roop,  "Mothproofing Without Pollution," JAATCC,  (5) No. 3,  1973

198.      stovall, J.,  "The  1972 Water Pollution Control Act Amendments Ana-
    lyzed," Modern Textiles,  (54) No. 2,  14-16,  19, 23, 1973.

199.      Little, A.H. , "Measures Taken Against Water Pollution in  the Textile
                                   195

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    Industry of Great Britain," Pure and Applied Chemistry, 29, 1-3,
    355-64, 1972.

200.      Eaddy, J.M., "Activated sludge Treatment of Textile Wastes to Meet
    High Stream Classifications - What Standards and How to Meet Them,"
    AATCC National Technical Conference, September 28-30, 1972.

201.      Williams, H.E., "Treatment and Reuse of Screen Printing Dye Waste
    waters," Paper presented at the 45th Annual conference of the Water
    Pollution Control Federation, October 8-13, 1972.

202.      Alspaugh, T.A., "Treating Dye Wastewaters," Paper presented at the
    Annual Conference of the Water Pollution Control Federation, October
    8-13, 1972.

203.      Rayburn, J.A., "Overall Problems.of Tertiary Treatment of Textile
    Waste for the Removal of Color, COD, TOC, Suspended Solids,
    Dissolved Solids, ere.," Paper presented at AATCC National Technical
    Conference, Philadelphia, Pa., September 28-30, 1972.

204.      "Color, Heavy Metal Removed by Adsorption," Chemical Processing,  (
    No.  9, 13, 1972.

205.      "Water Usage in the Wet Processing of Wool Textiles," wira Report

206.   Cosgrove, W.J., "water Pollution and the Textile Industry," Canadian
    Textile J., 63-6, January 1970.

207.      Eguchi, Y., and Y. Uda, "Wastewater Treatment by Granular Activate
    Carbon," J. Textile Machinery Soc. Japan,  (24) No. 8~, 555-61, 1971.

208.      Jones, T.R., "Textile Industry Wastes;  Effluent Treatment: Waste
    Reclamation: Man-made Fibers," Effluent & Water Treatment Journal,
    London, (12) No. 1, 352-355, July 1972.

209.      Simon-Hartley, "Treatment of Dyeing and Finishing Effluents from ;
    Textile Works," Intern. Dyer,  (143) No. 51, 53-4, January  2,  1970.

210.      Button, D.G., "Improved biological wastewater treatment," Du Pont
    Innovation,  (3) No. 1, 6-8,  1972.  (Eng.)

211.      Rhame, G.A., "Review of South Carolina Practices in Textile Finis
    Wastes," industrial Waste, 18 IW/U9-53, September-October  1972.

212.      "Textile Industry Wastes: Effluent Treatment: Water Reclamation:
    Great Britain," Textile Res. Conference, Final Report, 73  pages.

213.      Corning, V. , "Pollution Control in Jantzen Dyehouse,"  Knitting Ti
    (39) No. 35, 44-45, 1970.
                                   196

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214.     "Textile Water Pollution Cleanup Picks Up Speed," Textile World,
    54-66, November 1967.

215.     Sahlie, R.S., and C.E. Steinmetz, "Pilot Wastewater Study Gives
    Encouraging Indications," Modern Textiles,  (50)  No. 11, 20-28, 1969.

216.     "Trade Effluent control in the Carpet Industry," Textile Institute
    and Industry, (3)  No. 9, 237-40, 1965.
                                  197

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                              'SECTION XIV

                                GLOSSARY


acetate - A manufactured fiber made from cellulose acetate;.

acid dye - A type of dye commonly used to color wool and nylon but may
be used on other fibers.

Acrilan - Trademark of Monsanto for acrylic fiber.

acrylic - A manufactured fiber in which the fiber-forming substance is
any long chain synthetic polymer composed of at least 85% by weight of
acrylonitrile units.  Made in both filament and staple form.   (See
Acrilan, Orion, Creslan.)

Arnel - Trademark  (Celanese Corp.)  for cellulose triacetate fiber.

Avicron - Trademark  (FMC Corp.)  for rayon filament yarn.

Avril - Trademark  (FMC Corp.) for staple and filament rayon.

beck - A chamber in which goods may be scoured and dyed.  May be operated
at atmospheric pressure or at elevated temperature and pressure.

biphenyl  (or diphenyl) - A carrier used in dyeing polyester.

biochemical oxygen demand (BOD)  - A method of measuring rate of oxygen
usage due to biological oxidation.   A BODS of 1000 mg/liter means that
a sample  (1 liter)  used  1000 mg of oxygen in 5 days.

bleaching - Removal of colored components from a textile.  Common bleaches
are hydrogen peroxide, sodium hypochlorite, and sodium chlorite.

blend - the combination of two or more types of fibers and/or colors in
one yarn.

bottom chrome - Term used in application of certain dyes to wool.
Involves use of chromium compounds.

butyl benzoate - A carrier used in dyeing polyester.

carded - Yarn in which fibers are separated and aligned in a thin web,
then condensed into a continuous, untwisted strand called a "sliver."


carrier - An organic material used in dyeing polyester.   (See biphenyl,
orthophenyl phenol, trichlorobenzene, butyl benzoate.)
                                   198

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cationic dye - The colored component of this type of dye bears a
positive charge.

caustic soda - A strong alkali used, for example, in mercerizing.

cellulose - Major component of cotton and rayon.   Also used as the base
for acetate fiber.

chemical oxygen deman  (COD) - The amount of oxygen required to oxidize
materials in a sample by means of a dichromate solution.

combed cotton - Cotton yarn that is cleaned after carding by wire
brushes  (combs) and roller cards to remove all short fibers and
impurities.

crease-resistant - Fabrics that have been treated to make them resistant
to wrinkling.  One of the most common methods is  to incorporate a resin.

Creslan - Trademark owned by American Cyanamid Co. for acrylic fibers.

cross-dyed - Multicolored effects produced in one dye bath from fabrics
containing fibers with different affinities to the same dye.

Dacron - Trademark owned by Du Pont for polyester filaments and staple
fibers.

denier - Unit of weight indicating size of a fiber filament based on
weight in grams of a standard strand of 9000 meters.

desize - Removal of size.  Several methods may be used.  (See enzyme.)

developed dye - An azo dye whose color is developed by reaction on
cotton.

dichromate - A chemical used widely in applying some dyes.   Also used
in boiler water.  A toxic material.

fieldrin - Chemical applied to wool to eliminate damage due to moths.
Toxic.

diphenyl -  (see biphenyl).

direct dyes - Class of dyestuffs that colors cellulosic fibers in full
shades.

disperse dye - A type of dye used to color several synthetic fibers.
Applied as a fine dispersion using a carrier.  On cloth, padded dye
may be baked on or "thermofixed."
                                  199

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dissolved solids - Total solids - suspended solids in a sample of
waste water.

dope-dyed - Trade slang for "solution dyed" or "spun dyed" meaning that
color is put into the chemical liquid from which synthetic fibers are
drawn.  Filaments emerge colored.

double knit - Knitted fabric made on a special knitting machine that
combines a double set of needles to produce a fabric.

Durable Press - Goods that require no ironing during the normal use-
life of a garment.  The term applies to apparel and other textile
products such as sheets, draperies, etc.  As a rule, DP is achieved
in two ways:  1.  Pre-curing fabrics with a special resin finish then
pressing made-up garment.  2.  Post-curing fabric with a resin finish
then cooking made-up garments in an oven.  As a rule, polyester-cotton
blends are used, but there are 100% cottons, and other blends also.

enzyme - An agent used to remove starch size.

felt - A mat of fiber of wool often mixed with cotton or rayon.

flock - Short fibrous particles of fibers or short hairs applied by
various processes to the surface of a fabric.

fly - Waste fibers or particles which fly out into the air during
carding, drawing, spinning, or other fiber processing.

Fortrel - Trademark owned by Fiber Industries, Inc., for polyester
fiber.

greige - Fabrics in unbleached, undyed state before finishing.  In
U.S., "gray goods" or "grey goods."

Herculon - Trademark owned by Hercules, Inc., for polypropylene fibers.

jig-dyed - Dyed in open width on a machine called a "jig."  Cloth moves
from one roll to another through the dye liquor until the desired
shade is obtained.

jute - Coarse, brown fiber from the stalk of a bast plant grown in
India.  Used mainly fcr burlap, cordage, and as a backing for rugs
and carpets.

kier - A piece of equipment in which cotton is boiled with dilute
caustic soda to remove  impurities.  Also used as a  verb to describe
the process.
                                   200

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knitting - Process of making fabric by interlocking series cf loops
of one or more yarns.  Types are:  jersey  (circular knits), tricots
(warp knits), double knits.

Kodel - Trademark owned by Eastman Chemical Products Inc. for polyester
yarn and fiber.

Lycra - Trademark  (Du Pont) for polyurethane multifilament elastic
yarn.  The fused multifilaments in a bundle form a monofilament yarn
that stretches and snaps back.

mercerizing - Finish used on cotton yarns and fabrics to increase
luster, improve stretch and dyeability.  Treatment consists of im-
pregnating fabrics with cold concentrated sodium hydroxide solution.

Mitin - Trademark owned by Geigy Co., Inc. for a moth-repellent finish
for woolens.

modacrylic - Generic name established by the Federal Trade Commission
for a "manufactured fiber in which the fiber-forming substance is any
long-chain synthetic polymer composed of less than 85% but at least
35% by weight of acrylonitrile units."

mordant - A metallic salt used for fixing dyes on fibers.

naphthol dye - A azo dye whose color is formed by coupling with a
naphthol.  Used chiefly en cotton.

non-woven •* A material made of fibers in a web or mat generally held
together by a bonding agent.

nylon - Generic name for "a manufactured fiber in which the fiber-
forming substance is any long-chain synthetic polyamide having recurring
amide groups as an integral part of the polymer chain."

Orion - Trademark  (Du Pont) for acrylic fiber.

ortho phenyl phenol - A carrier used in dyeing polyester.

package dye - A method for dyeing many cones of yarn at once by
pumping a dye solution through the yarn.

permanent finish - Fabric treatments of various kinds to improve
glaze, hand,  or performance of fabrics.  These finishes are durable
to laundering.

pH scale - A method used to describe acidity or alkalinity.  pH 7
is neutral; above 7 - alkaline; below 7 - acid.  The scale extends
from 0 to 14 and a change of 1 unit represents a tenfold change in
                                  201

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acidity or alkalinity.

pigment prints - Made with insoluble pigment mixed with a binder and
thickener to form the printing paste.

pile fabric - Fabric with cut or uncut loops which stand up densely on
the surface.

polyamide -  (See nylon.)

polyester - A manufactured fiber in which the fiber-forming substance
is any long-chain synthetic polymer composed of at least 85* by weight
of an ester of dihydric alcohol and terephthalic acid.   (See Dacron,
Fortrel, Kodel.)

polypropylene - Basic fiber-forming substance for an olefin fiber.

precured fabric - Technique for imparting durable press by impregnating
fabrics with special resins then curing same.  Does not require oven
after-treatment of apparel.   (See durable press.)

Post-cured - Technique for imparting durable press that requires baking
apparel in ovens to cure fabrics that have been impregnated with special
resins.  Most common technique used with polyester and cotton blends.
(See durable press.)

printing - Process of producing designs of one or more colors on a
fabric.  There are several methods, such as roller, block, screen, etc.,
and several color techniques, such as direct, discharge, and resist.

print paste - A mixture containing a dye or pigment used in printing.
Generally contain gums  (thickener) and a solvent.   (See also pigment
prints.)


raschel - Warp-knit, similar to tricot, but coarser.  Made in a wide
variety of patterns.

rayon - A generic name for man-made fibers, monofilaments, and con-
tinuous filaments, made from regenerated cellulose.  Fibers produced
by both viscose and cuprammonium process are classified as rayon.

reactive dyes - Dyes that react chemically with the fiber.

resin - A chemical finish used to impart a property desired in a fabric,
such as water repellency or hand, etc.   (See durable press.)

resist dye - Method of treating yarn or cloth so that in dyeing the
treated parts do not absorb the dyestuff.
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roller prints - Machine made, using engraved copper rollers, one for
each color in the pattern.

scouring - Removal of foreign components from textiles.   Normal
scouring materials are alkalies (e.g., soda ash)  or trisodium phos-
phate, frequently used in the presence of a surfactant.   Textile
materials are sometimes scoured by use of a solvent.

screen prints - A screen of fine silk, nylon, polyester, or metal mesh
is employed.  Certain areas of the screen are treated to take dye,
others to resist dye.  A paste color is forced through the screen onto
the fabric by a "squeegee" to form the pattern.

sequestrant - A chemical used to bind foreign metal ions.  Frequently
used in dyeing.  A common sequestrant is EDTA.

size - A material applied to warp yarns to minimize abrasion during
weaving.  Common sizes are starch, polyvinyl alcohol  (PVOH), and
carbonxymethyl cellulcse.  Sizes are applied continuously in a slasher.

softener - A chemical used to apply a soft, pleasant hand.  Fat
derivatives and polyethylene are common softeners.

solution-dyed - Synthetic fibers sometimes are dyed by adding color
to the chemical polymer before fibers are formed.  Also called dope
dyed.

standard raw waste load  (SRWL) - A description of the properties of
waste water before treatment.

starch - Organic polymer material used as a size; highly biodegradeable.

sulfur dye - A class of dyes which dissolve in aqueous sodium sulfide
forming products with a marked affinity for cotton; the dyes are
regenerated by air oxidation.

suspended solids - Amount of solids separated by filtration of a
sample of waste water.

textured - Bulked yarns that have greater volume and surface interest
than conventional yarn of same fiber.

top chrome - Term used in application of certain dyes to wool.  Involves
use of chromium compounds.

top-dyed - wool which is dyed in the form of a loose rope of parallel
fibers prior to spinning fibers into yarn.
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total organic content (TOC) - The total organic materials present in
a sample of waste water.

total oxygen demand  (TOE) - The amounr. of oxygen necessary to completely
oxidize materials present in a sample of waste water.

total solids - Amount of residue obtained on evaporation of a sampla
of waste water.

triacetate - Differs from regular cellulose acetate, which is a di-
acetate.  The description implies the extent of acetylaticn and
degree of solubility in acetone.

tricot - Warp-knitted fabric.  Tricots are flat knitted with fine ribs
on the face (lengthwise) and ribs on the back  (widthwise).

tufted fabric - Fabric decorated with tufts of multiple ply yarns.
Usually hooked by needle into fabric structure.  Used widely for carpets.

vat dye - A type of dye applied from a liquor containing ailkali and a
powerful reducing agent, generally hydrosulfite.  The dye is subsequently
oxidized to the colored form.  Widely used on cellulosic fibers.

warp - Set of lenthwise yarns in a loom through which the crosswise
filling yarns  (weft) are interlaced.  Sometimes called "ends."

weaving - The process of manufacturing fabric by interlacing a series
of warp yarns with filling yarns at right angles.

yarn - An assemblage of fibers or filaments, either manufactured or
natural, twisted or laid together so as to form a continuous strand
which can be used in weaving, knitting, or otherwise made into a
textile material.

yarn-dyed - Fabrics in which the yarn is dyed before weaving or
knitting.
                                  204

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                                   METRIC UNITS
                                 CONVERSION TABLE

MULTIPLY (ENGLISH UNITS)                   by                TO OBTAIN  (METRIC UNITS)

    ENGLISH UNIT      ABBREVIATION    CONVERSION   ABBREVIATION   METRIC UNIT
acre                    ac
acre - feet             ac ft
British Thermal
  Unit                  BTU
British Thermal
  Unit/pound            BTU/lb
cubic feet/minute       cfm
cubic feet/second       cfs
cubic feet              cu ft
cubic feet              cu ft
cubic inches            cu in
degree Fahrenheit       F°
feet                    ft
gallon                  gal
gallon/minute           gpm
horsepower              hp
inches                  in
inches of mercury       in Hg
pounds                  Ib
million gallons/day     mgd
mile                    mi
pound/square
  inch (gauge)          psig
square feet             sq ft
square inches           sq in
tons (short)            t
yard                    y
       0.405
    1233.5

       0.252
ha
cu m

kg cal
0.555
0.028
1.7
0.028
28.32
16.39
0.555(°F-32)*
0.3048
3.785
0.0631
0.7457
2.54
0.03342
0.454
3,785
1.609
kg cal/kg
cu m/min
cu m/min
cu m
1
cu cm
°C
m
1
I/sec
kw
cm
atm
kg
cu m/day
km
(0.06805 psig +1)*  atm
       0.0929       sq m
       6.452        sq cm
       0.907        kkg
       0,9144       m
hectares
cubic meters

kilogram - calories

kilogram calories/kilogram
cubic meters/minute
cubic meters/minute
cubic meters
liters
cubic centimeters
degree Centigrade
meters
liters
liters/second
killowatts
centimeters
atmospheres
kilograms
cubic meters/day
kilometer

atmospheres (absolute)
square meters
square centimeters
metric tons (1000 kilograms)
meters
* Actual conversion, not a multiplier

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