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 Chromium
.Chromium appears in the nonprojcess  discharges  mainly from the  cooling
 tower  blowdown.   Chromium compounds are sometimes used as a corrosion
 inhibitor and are added to the] tower basin  or   cooling  tower  makeup.
 Chromimum was not detected in the process waste water effluent.

 Chromium,  in its various valence states, is hazardous to man.   It can
 produce lung tumors when  inhaled  and  induces  skin  sensitizations.
 Large  doses  of  chromates  have  corrosive effects on the intestinal
 tract and can cause inflammation of the kidneys.   Levels  of  chromate
 ions  that  have  no  effect ojn man appear  to  be so low as to prohibit
 determination to date.         i

 The tdxicity of chromium salts toward aquatic  life varies widely  with
 the species, temperature, pH, valence of the chromium, and synergistic
 or  antagonistic  effects,  especially  that   of  hardness.   Fish are
 relatively tolerant of chromium salts, but  fish  food  organisms  and
 other  lower  forms of aguaticj life are extremely sensitive.  Chromium
 also inhibits the growth of algae.
                               j   -                         .
 In some agricultural crop's, chromium can cause reduced growth or death
 of the crop. .Adverse effects jof low  concentrations  of  chromium  on
 corn, tobacco and sugar beets have  been documented.
                               i   -
 Summary of Significant Pollutants

 Of  the  pollutants  examined,]  only  COD,  suspended  solids,  oil and
 grease, lead, and pH are significant characteristics when  considering
 process  waste waters.   Of the' five, suspended solids, oil and grease,
 lead, and pH must be controlled. The list  of  control  parameters,  for
 Subcategories E, F, and G therefore is:

     Suspended Solids          j
     Oil and Grease            i
     Lead                 . '    !
     PH         .               |   .

 Subcateqory H and Subcateqory II —  Reclaimed Rubber

 Review  of  published  literature,  EPA documents and industry records,
 and the findings of the  plant  visits  indicate .that  'the  following
 chemical   and   biological   jconstituents  are  pollutants  found  in
 measurable quantities from Subcategory H and Subcategory I effluents:
                               !    '
     BOD
     COD
     Suspended Solids
     Total Dissolved Solids
     Oil and Grease
                              •I 99

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     PH
     Temperature
     Zinc
                 •                I  -      .......'..
 Biochemical  Oxygen Demand  JBODj  j

 The  presence of BOD in Subcategory   H   process  waste  waters   is  due
 primarily  -to  the  use of   larjje quantities of  process waters in the
 digestion  of scrap  rubber.   This   waste  water  is  not  evolved  in
 Subcategory   I   production  facilities.   A  second  source  of BOD is
 organics found  in  the  condensed  vapors  collected  from both Subcategory
 H and  Subcategory  I depolymerizajbicn units.  Organics found  in anti-
 tack  solution   discharges contribute additional  BOD.  The possibility
 exists that  pollutants with  a high COD/BOD ratio  may be discharged  by
 plants  utilizing   the wet   digestion  process.   Control of COD by in-
 plant  and  end-of-pipe  controls   ifill adequately  reduce  BOD   without
 requiring  the additional monitoring  costs of both analyses.

 Biochemical   oxygen demand  (BOD) is a  measure of the oxygen consuming
 capabilities of organic matter.  ]The BOD  does  not  in  itself cause
 direct harm  to  a water system, but it does exert  an indirect effect by
 depressing  the oxygen content of the water.  Sewage and other  organic
 effluents  during their processes!of  decomposition exert a  BOD,  which
 can  have  a catastrophic effect   on  the ecosystem by depleting the
 oxygen supply.   Conditions are reached  frequently where  all   of  the
 oxygen  is used and the continuing decay process  causes the production
 of noxious gases such  as hydrogefl sulfide and methane.  Water   with  a
 high  BOD  indicates   the  presence  of decomposing organic matter and
 subsequent  high  bacterial  counts  that  degrade  its  quality   and
 potential  uses.                  j •
                                 j                                  ' .
 Dissolved  oxygen   (DO)  is  a  vfater  quality  constituent  that,  in
 appropriate  concentrations, is essential not only  to  keep  organisms
 living but   also   to   sustain  species  reproduction,  vigor,  and the
 development  of  populations.  Organisms undergo stress  at  reduced  DO
 concentrations  that   make them| less competitive and able to  sustain
 their  species within the aquatic jenvironment.  For example, reduced DO
 concentrations  have been   shown  jto  interfere  with  fish  population
 through  delayed   hatching of eggs, reduced size and vigor of embryos,
 production of deformities in young, interference with food  digestion,
 acceleration    of  blood  clottirig,  decreased  tolerance  to  certain
 toxicants,  reduced  food  efficiency  and  growth  rate,   and  reduced
 maximum  sustained  swimming  speed.   Fish food organisms are likewise
 affected adversely  in  conditions  with  suppressed  DO.   Since  all
 aerobic  aquatic  organisms  need,  a  certain  amount  of  oxygen, the
 consequences of total  lack of dissolved oxygen due to a high  BOD  can
kill all inhabitants of the affeqted area.

If a high BOD is present,  the quality of the water is usually visually
degraded by the presence of decomposing materials and algae blooms due
                                                                              f
                             100

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                                        I   •-  .             "
     '"'                                  I

          to  the  uptake  of degraded  materials that form the foodstuffs of the
          algal populations.            |

          COD       '                    I

          The presence of organics and  inorganics  in  dewatering  waste  waters
          will  contribute  to  high COD concentrations in Subcategory H process
          waste waters.  Values for this waste stream  are  greater  than  3,000
          mg/1.   Other  contributors of COD include organics found in condensed
          vapor streams for depolymerization units and anti-tack solutions  used
          in  both  Subcategory  H  andj Subcategory  I  production  facilities.
          Concentrations in these latter sources ranged from  approximately  100
          mg/1   to  3HO  mg/1.   A  latge  portion  of  this  COD  is  directly
          attributable to the oil content of these waste streams.   However,  to
          prevent   excessive   discharge  of  non-biodegradable  organics  (not
          attributable to oil and grease) COD shall be monitored and controlled.

          Suspended Solids              I
                ~   -     ~              !••
          Suspended  Solids  (SS)  in   ^ubcategory  H  and  Subcategory  I   are
          attributable to washdcwn and  innoff from compounding areas, discharges
          of  anti-tack  solution, boiler blowdowns, and water treatment wastes.
          Additional loadings in  Subcategory  H  discharges  will  result  when
          fiberous  stock is fed to the!digesters.  In this case, the dewatering
          liquor can contain as much as!10-percent suspended solids.

,          Suspended solids include both!organic and  inorganic  materials.   The
          inorganic , components  include  sand,  silt,  and  clay.   The organic
          fraction includes such materials  as  grease,  oil,  tar,  animal  and
          vegetable  fats,  various fibers, sawdust, hair, and various materials
          from sewers.  These solids ma^ settle out rapidly and bottom  deposits
          are  often  a  mixture  of  both  organic  and inorganic solids.  They
          adversely affect fisheries by]covering the bottom  of  the  stream  or
          lake  with  a  blanket  of material that destroys the fish-food bottom
          fauna or the spawning ground  pf  "fish.   Deposits  containing  organic
          materials  may  deplete  bottbm  oxygen  supplies and produce hydrogen
          sulfide, carbon dioxide, methane, and other noxious gases.

          In raw water sources for domestic use,  state  and  regional  agencies
        .  generally  specify  that  suspended  solids  in  streams  shall not be
          present  in  sufficient  concentration  to  be  objectionable  or   to
          interfere  with normal treatment processes.  Suspended solids in water
          may interfere with many industrial processes,  and  cause  foaming  in
          boilers, or encrustations on  Equipment exposed to water, especially as
          the  temperature rises.  Suspended solids are undesirable in water for
  '        textile  industries;  paper   ind  pulp;  beverages;  dairy   products;
          laundries;  dyeing;  photography;  cooling  systems, and power plants.
          Suspended particles also serve as a transport mechanism for pesticides
        .  and other substances which  are  readily  sorbed  into  or  onto  clay
          particles.
                                           101

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Solids  may  be  suspended in water  for  a time, and then settle to the
bed of the stream or lake.  These settleable  solids " discharged  with
man's  wastes may be inert, slowly biodegradable materials, or rapidly
decomposable substances.   While I in suspension,  they  increase  the
turbidity  of  the  water,  reduce   light  penetration  and impair the
photosynthetic activity of aquatic plants.
                                 i             "
Solids in suspension are aesthetically displeasing.  When they  settle
to form sludge deposits on the stream or lake bed, they are often much
more  damaging  to  the life in Water, and they retain the capacity to
displease the senses.  Solids, when  transformed  to  sludge  deposits,
may  do  a variety of damaging things, including blanketing the stream
or lake bed and thereby destroying the living spaces for those benthic
organisms that would otherwise occupy the habitat.  When of an organic
and therefore decomposable nature', solids use a portion or all of  the
dissolved  oxygen available in the area,  organic materials also serve
as  a  seemingly  inexhaustible  food  source  for   sludgeworms   and
associated organisms.

Turbidity  is  principally a measure of  the light absorbing properties
of^suspended solids.  It is frequently used as a substitute method  of
quickly  estimating  the total suspended solids when the concentration
is relatively low.               I
Dissolved Solids                 j

Dissolved Solids  (TDS)  found  in1  Subcategory  H  and  Subcategory  I
effluents are attributable to nonprocess waste water effluents.  These
include  cooling tower and boiler! blowdowns and water treatment system
backwashes and blowdown.         j   "
                                • i
In natural waters the dissolved s|olids consist mainly  of  carbonates,
chlorides,  sulfates,  phosphates,  and  possibly nitrates of calcium,
magnesium, sodium, and potassium,
other substances.
with traces of iron,  manganese  and
Many communities in the United States and in other countries use water
supplies  containing  2000  to  4:000  mg/1 of dissolved salts, when no
better water is available.  Such jwaters are  not  palatable,  may  not
quench  thirst,  and  may have a (laxative action on new users.  Waters
containing more than 4000 mg/1 of- total salts are generally considered
unfit for human  use,  although  |in  hot  climates  such  higher  salt
concentrations can be tolerated wlhereas they could not be in temperate
climates.   Waters  containing  5!000  mg/1  or more are reported to be
bitter and act as bladder and intestinal irritants.  It  is  generally
agreed that the salt concentration of good, palatable water should not
exceed 500 mg/1.
                             102

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Limiting  Concentrations  Of dissolved solids for fresh-water fish may
range from 5,000 to  10,000  mg/1,  according  to  species  and  prior
acclimatization.   Some  fish  are  adapted  to  living in more saline
waters, and a few species of fresh-water  forms  have  been  found  in
natural  waters  with  a  saljt concentration of 15,000 to 20,000 mg/1.
Fish can slowly become acclimatized to higher salinities, but fish  in
waters  of  low  salinity  cannot  survive  sudden  exposure  to  high
salinities, such as  those  resulting  from  discharges  of  oil  well
brines.   Dissolved  solids may influence the toxicity of heavy metals
and organic compounds  to  fish  and  other  aquatic  life,,  primarily
because of the antagonistic effect of hardness on metals.

Waters  with  total  dissolved  solids  over  500 mg/1 have decreasing
utility as irrigation water.  At 5,000 mg/1 water  has  little  or  no
value for irrigation.    'I
     >                        '                            •
Dissolved solids in industrial waters can cause foaming in boilers and
cause  interference  -with  cleaness,  color, or taste of many finished
products.  High contents of dissolved solids also tend  to  accelerate
corrosion.                   ]
                             I       .....  ... , I  v  ',
Specific  conductance  is a measure of the capacity of water to convey
an  electric  current.  - This,  property  is  related  to   the   total
concentration  of  ionized  substances in water and water temperature.
This property is frequently used as a  substitute  method  of  quickly
estimating the dissolved soliids concentration.
Oil and Grease
                             I
Oil  and grease in process waste waters in Subcategory H are primarily
attributable to process oil used in the digester process.  This oil is
carried to the effluent with the dewatering liquor..   Sources  of  oil
and grease common to both Subcategory H and Subcategory I are organics
scrubbed  from  vapor  stream's  and lubricating oil leakage from heavy
machinery.  The oil concentrajtion in the total effluent of the  plants
visited  was  less than 10 mg/1.  However, company data indicated that
concentrations In process streams could be as high as 10,000 mg/1.

Oil and grease exhibit an oxygen demand.  Oil emulsions may adhere  to
the  gills  of  fish  or  coat  and  destroy  algae or other plankton.
Deposition of oil in the bottkun sediments can serve to inhibit  normal
benthic  growths,  thus  interrupting the aquatic food chain.  Soluble
and emulsified material ingested by fish may taint the flavor  of  the
fish  flesh.  Water soluble components may exert toxic action OKI fish.
Floating oil may reduce the re-aeration of the water  surface, and  in.
conjunction  with  emulsified  oil  may interfere with photosynthesis.
Water insoluble components dalmage  the  plumage  and  coats  of  water
animals  and  fowl.   Oil  and  grease  in  a  water can result in the
formation  of  objectionable j surface  slicks  preventing   the   full
aesthetic enjoyment of the wajter.
                              03

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

eSU. Acidity and AlkalinitY        j

Variations  in  pH  of  Subcategory  H  process  effluents  is  highly
dependent   on  the  formula  use&  in  digestion.   Plant-visit  data
indicated a minimum pH of 6.0.  Industry data indicate a maximum pH of
approximately 11.0.  Fluctuations]in Subcategory I process waste water
pH are not expected to be outsideithe pH range of 6.0 to 9.0.

Acidity and alkalinity are reciprocal terms.  Acidity is  produced  by
substances  that yield hydrogen ions upon hydrolysis and alkalinity is
produced by substances that yield|hydroxyl  ions.   The  terms  "total
acidity"  and  "total  alkalinity','  are  often  used  to  express  the
buffering capacity of a solution.] Acidity in natural waters is caused
by carbon dioxide, mineral acids, weakly dissociated  acids,  and  the
salts  of strong acids and weak bases.  Alkalinity is caused by strong
bases and the salts of strong alkalies and weak acids.

The term pH is  a  logarithmic  expression  of  the  concentration  of
hydrogen  ions.   At  a  pH  of  7r  the  hydrogen  and  hydroxyl  ion
concentrations are essentially equal and the water is neutral.   Lower
pH  values  indicate  acidity while higher values indicate alkalinity.
The  relationship  between  pH  aijid  acidity  or  alkalinity  is   not
necessarily linear or direct.     I

Waters  with  a  pH below 6.0 are|corrosive to water works structures,
distribution lines, and household|plumbing fixtures and can  thus  add
such constituents to drinking water as iron, copper, zinc, cadmium* and
lead.   The  hydrogen  ion concentration can affect the "taste" of the
water.  At a low pH water tastes Msour".  The bactericidal  effect  of
chlorine  is  weakened  as the pHjincreases, and it is advantageous to
keep the pH close to 7.  This is very significant for  providing  safe
drinking water.

Extremes of pH or rapid pH changes can exert stress conditions or kill
aquatic  life  outright.   Dead fish, associated algal blooms, and foul
stenches are aesthetic liabilities of  any  waterway.   Even  moderate
changes  from  "acceptable"  criteria  limits of pH are deleterious to
some species.   The relative toxicity to aquatic life of many materials
is increased by changes in the water pH.  Metalocyanide complexes  can
increase a thousand-fold in toxicity with a drop of 1.5 pH units.  The
availability  of  many  nutrient substances varies with the alkalinity
and acidity.   Ammonia is more lethal with a higher pH.
The lacrimal fluid of the human eye has a pH of approximately 7.0  and
a  deviation of 0.1 pH unit from the norm may result in eye irritation
for the swimmer.  Appreciable irritation will cause severe pain.
                                  I
                             104

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 Temperature
 In  reclaim  plants,  there  areiindividual  waste water streams,   such   as
 condenser   flows,   which   have   elevated  temperatures.  However, once
 combined with  other  effluents,   elevated  temperature  in  the  final
 effluent is not  a  problem.

 Temperature is one  of the most important and influential water quality
 characteristics.    Temperature   determines  those  species that  may  be
 present| it activates the hatching  of young, regulates their activity,
 and  stimulates  or  suppresses   their   growth  and development;    it
 attracts,   and  may  kill wljen   the  water becomes too hot or becomes
 chilled too suddenly,  colder water generally suppresses  development.
 Warmer water generally accelerates  activity and  may be a primary cause
 of  aquatic plant  nuisances  when other  environmental  factors are
 suitable.

 Temperature is a prime regulator of natural processes within the water
 environment.   It governs  physiological   functions  in  organisms and,
 acting  directly or indirectly in combination with  other water quality
 constituents,  it affects  aquatic life with each  change.  These effects
 include  chemical   reaction  Irates,  enzymatic  functions,   molecular
 movements,   and  molecular  ejxchanges  between  membranes  within  and
 between the physiological systems and the organs of an animal.

 Chemical reaction rates vary [with temperature and  generally   increase
 as  the  temperature   is  increased.  The solubility of gases  in water
 varies with temperature.  Dissolved oxygen is decreased by  the  decay
 or  decomposition   of  dissolved organic substances and the decay rate
 increases as the temperature bf  the water increases  reaching a maximum
 at about 30<>c  <86°F) .  The temperature of stream water,  even  during
 summer,  is  below  the   optimum for  pollution-associated  bacteria.
 Increasing   the   water   tejmperature    increases    the    bacterial
 multiplication rate  when  the  environment is  favorable and  the food
 supply is abundant.

 Reproduction   cycles  may  be  changed   significantly   by   increased
 temperature    because  this  {function  takes  place  under  restricted
 temperature  ranges.   Spawning  may  not   occur   at   all   because
 temperatures   are  too  high.   Thus, a  fish population may exist in a
 heated area only by continued immigration.   Disregarding the decreased
 reproductive potential,  water  temperatures need   not  reach   lethal
 levels  .to  decimate  a specites.   Temperatures that  favor competitors,
 predators,  parasites, and disease can destroy a  species at levels  far
 below those that are lethal.

 Fish food organisms are altered severely when temperatures approach or
 exceed  90°F.  Predominant al^ral species  change,  primary production is
 decreased,  and bottom associated organisms may be depleted or  altered
drastically in numbers and distribution.   Increased water temperatures
                             05

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         may cause aquatic plant nuisances
         favorable.
when other environmental factors are
         Synergistic  actions  of  pollutants  are  more severe at higher water
         temperatures.  Given amounts  of j domestic  sewage,  refinery  wastes,
         oils,  tars,  insecticides,  detergents,  and fertilizers more rapidly
         deplete oxygen in water at higher]  temperatures,  and  the  respective
         toxicities are likewise increasef
         When  water  temperatures  increase, the predominant algal species may
         change from diatoms to green algae, and finally at  high  temperatures
         to  blue-green  algae,  because  |of species temperature preferentials.
         Blue-green algae can cause serioujs  odor  problems.   The  number  and
         distribution  of  benthic  organisms  decreases  as water temperatures
         increase above 90»F, which is clo|se to the  tolerance  limit  for  1-he
         population.   This  could seriously affect certain .fish that depend on
_.        benthic organisms as a food source.
 ..                      ,        .          ,         ..........
         The cost of fish being attracted jto heated water in winter months  may
 . j       be considerable, due to fish mortalities that may result when the fish
         return to the cooler water.

         Rising  temperatures  stimulate the decomposition of sludge, formation
         of sludge  gas,  multiplication  jof  saprophytic  bacteria  and  fungi
         (particularly  in the presence of! organic wastes), and the consumption
         of oxygen by putrefactive processes, thus affecting the esthetic value
         of a water course.

         In general, marine water  temperatures do  not  change  as  rapidly  or
         range  as  widely as those of frejsh water.   Marine and estuarine fish,
         therefore, are less tolerant of tjemperature variation.   Although  this
         limited  tolerance  is greater in estuarine than in open water marine
         species, temperature changes are  more  important  to  those  fish  in
         estuaries  and bays than  to those in open marine areas, because of the
         nursery and  replenishment  functions  of  the  estuary  that  can  be
         adversely affected by extreme temperature changes.
         Subcategory H processes  which would result in zinc-laden effluents  cire
         not   utilized  by   industry,  therefore  zinc  is   not  considered  a
         signficant parameter.  However,  historical data  from industry indicate
         that,  with certain  digestion formulations, zinc  content  could  be   as
         high  as  1,700  mg/1.   This  same  data  stated  that  this zinc  was
         treatable and could  be reduced  to
         dewatering stream.
less than 10 mg/1 in  the  digestion
                                        106

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Summary of Significant. Pollutants

Of  •the  pollutants examined, suspended solids, oil and grease, and pH
are significant characteristics when considering process waste  waters
from  Subcategory  H  and Subcjategory I reclaim facilities.  COD is an
additional contaminant which is  significant  when  considering  waste
waters from Subcategory H facilities.  The recommended list of control
parameters for each Subcategory is as follows:
    Subcateorory H

    COD
    Suspended Solids
    Oil and Grease
    pH
                                      Subcateqory T

                                      Suspended Solids
                                      Oil and Grease
                                      PH
Subcateqories J and K -- Latex-Based Products  .

Review  of  published literature, EPA documents, industry records, and
findings of the plant visits indicated that  the  following  chemical.
                              constituents  are  found  in  measurable
                              effluents from facilities  manufacturing
physical,   and   biological
quantities in the waste water
latex-based products:

    BOD
    COD
    Suspended Solids
    Total Dissolved Solids
    Oil and Grease
    pH
    Surfactants
    Color
    Temperature (Heat)
    Chromium
    Zinc

The  principal  differences  between  the  waste  water  generated  in
Subcategory  J  (latex  dipping,  thread,  and   porous   molds)   and
Subcategory  K.  (latex  foam)
chromium, and zinc.

Biochemical Oxygen Demand
                               plants  lie  in  loadings for BOD, COD,
BOD is attributable to the various  organic  compounds  which  contact
process  waste  waters.   For I Subcategory  J  production  facilities,
concentrations and  loadings  iare  highly  dependent  on  the  product
washing , technique  employed, j  Concentrations  range  from 130 to 150
mg/1.  The BOD in waste water 'generated in  Subcategory  K  production
facilities  is  again  attributable to wash waters, but concentrations
are much higher, ranging as high as 4,900 mg/1.
                               107

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COD

Moderate to high COD concentrations
K process waste waters for the sanje
BOD  concentration.   Concentration^
Subcategory J facilities and as hi1
facilities.  EPA is conducting eva!
and  resultant  economic  impact fJ
rubber processing regulations.

Suspended Solids
                                     are present in  Subcategories J  and
                                     reasons as those indicated  for  the
                                    s range  from   175  to  675 mg/1  for
                                    h as 29,000 mg/1 for Subcategory K
                                    uations of COD control  technologies
                                    r possible future amendments to  the
contamination
washdown  and
cleanout  wastes.
                                108
                                                       result from
                                      ,     .uncoagulated  latex  from
                                   Loadings in the effluents depend on

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                           '  • I               •
                             . -I    .   . .       -
washing techniques employed anjd not on the type of  product.   Typical
values ranged from 80 to over 3,000 mg/1.

Suspended  solids  include  both organic and inorganic materials,.  The
inorganic components  include  sand,  silt,  and  clay.   The  organic
fraction  includes  such  materials  as  grease,  oil, tar, animal and
vegetable fats, various fibers], sawdust, hair, and  various  materials
from  sewers.  These solids maly settle out rapidly and bottom deposits
are often a mixture  of  both [organic  and  inorganic  solids.   They
adversely  affect  fisheries  by  covering the bottom of the stream or
lake with a blanket of material that  destroys  the  fish-food  bottom
fauna  or  the  spawning  groulnd of fish.  Deposits containing organic
materials may deplete bottom  joxygen  supplies  and  produce  hydrogen
sulfide, carbon dioxide, methane, and other  noxious gases.

In  raw  water  sources  for domestic use, state and regional agencies
generally specify that  suspended  solids  in  streams  shall  mot  be
present   in  sufficient  concentration  to  be  objectionable  or  to
interfere with normal treatment processes.   Suspended solids in  water
may  interfere  with  many  industrial processes, and cause fGaining in
boilers, or encrustations on equipment exposed to water, especially as
the temperature rises.  Suspended solids are undesirable in water  for
textile   industries;  paper  and  pulp;  beverages;  dairy  products;
laundries; dyeing; photography; cooling  systems,  and  power  plants.
Suspended particles also serve as a  transport mechanism for pesticides
and  other  substances  which  are   readily  sorbed  into  or onto clay
particles.

Solids may be suspended in water for a time, and then  settle  to  the
bed  of   the  stream  or lake.j These settleable solids discharged with
man's wastes may be  inert,  slowly biodegradable materials, or  rapidly
decomposable  substances.    Wliile  in  suspension,  they   increase the
turbidity of the   water,  reduce  light  penetration   and   impair  the
photosynthetic  activity of  aquatic plants.

Solids   in  suspension are aesthetically  displeasing.   When they  settle
to form sludge  deposits on  the  stream or lake bed, they are often much
more damaging to the life  in ijrater,  and they retain   the   capacity  to
displease  the   senses.    Solids, when  transformed to sludge deposits,
may do  a variety  of  damaging things, including  blanketing  the  stream
or lake bed and thereby destroying  the  living spaces  for  those benthic
organisms that  would otherwise occupy the  habitat.  When  of an organic
 and  therefore  decomposable nature,  solids use  a  portion  or all  of  the
 dissolved oxygen  available in!the area.  Organic  materials also   serve
 as   a    seemingly  inexhaustible  food  source  for   sludgeworms   and
 associated organisms.

Turbidity is principally  a measure  of the light  absorbing  properties
 of  suspended solids.  It is -frequently used as a substitute method of
                                 109
                                                                            1

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         suspended solids when
            l
            I  - - .•  -     - •-
                                                          concentration
 Dissolved Solids
                 data'  xt was deermined that TDS in process effluents
                    J*  and  K  Production  facilities  were  primarily
 discnar                "" lntakf Water ** nOt tO Pr°cess wafte wSer
  hT         watf" the dissolved solids consist mainly  of  carbonates,
 chlorides,   sulfates,  phosphate,  and  possibly nitrates of calcium!
                                                                   "
                        P°taSSiUm' With traces of
                                                         manganese
 Many communities  in the United States and in other countries use water
 supples   containing  2000  to  4000  mg/1 of dissolved salts,  when no
 better water  is  available.   Such
 quench  thirst,   and  may have a
            waters  are   not  palatable.
                               may  not
                  4           «r	— — r  •" J[  »*%ir v.
            laxative  action on new users.  Waters
 -  ....         ,,     — j  ---- ~ ~ —»»«.*• v. j. »^ awi_j.
-------
 concentration  of   ionized  substances in water  and water  temperciture.
 This property is frequently used as a  substitute method   of  quickly
 estimating the dissolved  solidjs  concentration.

 Oil  and Grease

 Oil   and grease is present at low concentrations in the process waste
 waters   of  all  types  of  Subcategories J  and K  plants.   it  is
 attributable to organics  used in coagulation agents and wash waters.

 Oil   and grease exhibit an oxygen demand,  oil emulsions may adhere to
 the  gills of fish   or  coat  and  destroy algae  or  other plankton.
 Deposition  of oil  in the bottom sediments can serve to inhibit normal
 benthic growths, thus interrupting the aquatic  food  chain.    Soluble
 and   emulsified  material ingested by fish may taint the flavor of the
 fish flesh.  Water  soluble components may exert toxic action on fish.
 Floating oil  may  reduce the | re-aeration of the water surface and in
 conjunction with emulsified oil   may  interfere   with  photosynthesis.
 Water  insoluble  components  damage  the plumage  and coats of water
 animals and fowl,   oil and  grease  in a water  can  result   in  the
 formation   of   objectionable  surface   slicks   preventing the  full
 aesthetic enjoyment of the water.
Oil spills can damage  the  surface  of  boats  and  can
aesthetic characteristics of beaches and shorelines.

    Acidity and Alkalinity
                                                          destroy  the
Control  and  adjustment  of  pH  in process waste waters generated in
Subcategories J and K production facilities is often  necessary  as  a
prerequisite  for the chemical coagulation treatment process.  In view
of this it is feasible that the  uncontrolled  effluent  pH  can
appreciably and should be limited to an acceptable range.

Acidity  and  alkalinity are reciprocal terms.  Acidity is produced by
^l*«V% f*-^ ^ _. *tm **. *•* ^IKA.!- —_J ._. ^ .3 \	m	    •         .  _  __       _    •         "
                                                                  vary
substances that yield hydrogen
                               ions upon hydrolysis and alkalinity  is
produced  oy  sucstances  tnat  yield hydroxyl ions.  The terms "total
acidity"  and  "total  alkalinity"  are  often  used  to  express  the
buffering capacity of a solution.  Acidity in natural waters is caused
by  carbon  dioxide,  mineral acids, weakly dissociated acids, and the
salts of strong acids and weak [bases.  Alkalinity is caused by  strong
bases and the salts of strong alkalies and weak acids.
                               I
The  term  pH  is  a
hydrogen  ions.   At
                      logarithmic  expression  of the concentration of"
                      a  pH  of  7,  the  hydrogen  and  hydroxyl  ion
concentrations  are essentially equal and the water is neutral.  Lower
pH values indicate acidity while higher  values  indicate  alkalinity.
The   relationship  between  pH  and  acidity  or  alkalinity  is  not
necessarily linear or direct.
                              m
-------
 Waters with a pH below 6.0 are corrosive to  water  works  structures.
 distribution  lines,   and household plumbing fixtures and can thus add
 such constituents to drinking watjer as iron, copper, zinc, cadmium and
 lead.  The hydrogen ion concentration can affect the  "taste"  of  the
 water.   At  a low pH water tasters "sour".  The bactericidal effect of
 chlorine is weakened as the pH increases, and it  is  advantageous  to
 keep  the  pH close to 7.  This is very significant for providing safe
 drinking water.                                                  y

 Extremes of pH or rapid pH changes can exert stress conditions or kill
 aquatic life outright.  Dead fisri, associated algal blooms,   and  foul
 stenches  are  aesthetic  liabilities  of any waterway.   Even moderate
 changes from "acceptable" criteria limits of  pH  are  deleterious  to
 some species.   The relative toxidity to aquatic life of many materials
 is   increased by changes in the water pH.  Metalocyanide complexes can
 increase a thousand-fold in toxidity with a drop of 1.5  pH units.   The
 availability of  many  nutrient substances varies  with  the  alkalinity
 and acidity.  .Ammonia is more lethal with a higher pH.

 The  lacrimal fluid of the human 'eye has a pH of approximately 7.0 and
 a deviation of 0.1 pH unit from the ncrm may result in  eye  irritation
 for the swimmer.   Appreciable irritation will cause severe pain.
                                   . ''••I.,'- ''.  •   --.  •  •..••-'   '-..,   •
 Surfactants

 Surfactants   will   be   present!    in  wash  waters evolved  in   ail
 Subcategories  J   and   K  production  facilities.    Surfactants  are a
 primary  cause  of foamy plant effluents,however,  their  concentrations
 in  process  waste waters are low.   '	•—•
 mg/1.

 Color
Concentrations range  from  2  to  6
Color  is  objectionable from an aesthetic standpoint and also because
it interferes with the transmission of sunlight into streams,  thereby
lessening  photosynthetic  activity.  Some waste streams which contaiin
latex can have appreciable color. I  Generally, color  for  latex  based
industries  is  associated with suspended solids loadings and can best
be monitored by this parameter.

Temperature

Temperature is not a significant parameter  when  considering  process
waste  streams.    CertaiA  wash  Caters  can  have  a  moderately high
temperature, but dilution with otl^er  effluent  streams  significantly
reduces their impact.            I              ,

Temperature is one of the most important and influential water quality
characteristics.    Temperature  determines  those  species that may be
present;  it activates the hatching cf young, regulates their activity,
                            112
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and  stimulates  or  suppresses  their  growth  and  development;   it
attracts,  and  may  kill  wh4n  the  water becomes too hot or becomes
chilled too suddenly.  Colder |water generally suppresses  development.
Warmer water generally accelerates activity and may be a primary cause
of  aquatic  plant  nuisances  when  other  environmental  factors are
suitable.

Temperature is a prime regulatjor of natural processes within the water
environment.  It governs physiological  functions  in  organisms  and,
acting  directly or indirectly in combination with other water quality
constituents, it affects aquatic life with each change.  These effects
include  chemical  reaction  ifates,  enzymatic  functions,   molecular
movements,  and  molecular  exchanges  between  membranes  within  and
between the physiological systems and the organs of an animal.

Chemical reaction rates vary *ith temperature and  generally  increase
as  the  temperature  is  increased.  The solubility of gases in water
varies with temperature.  Dissolved oxygen is decreased by  the  decay
or  decomposition  of  dissolved organic substances and the decay rate
increases as -the temperature qf the water increases reaching a maximum
at about 30°C (86°F).  The temperature of stream  water,  even  during
summer,  is  below  the  optimum  for  pollution-associated  bacteria.
Increasing   the   water   temperature   increases    the    bacterial
multiplication  rate  when  the  environment is favorable and the food
supply is abundant.

Reproduction  cycles  may  be  changed  significantly   by   increased
temperature   because  this  function  takes  place  under  restricted
temperature  ranges.    Spawning  may  not   occur   at   all   because
temperatures  are  too  high. I  Thus, a fish population may exist in a
heated area only by continued immigration.  Disregarding the decreased
reproductive potential,  water  temperatures  need  not  reach  lethal
levels  to  decimate  a specie's,  Temperatures that favor competitors,
predators, parasites, and disease can destroy a species at levels  far
below those that are lethal.  |

Fish food organisms are altered severely when temperatures approach or
exceed  90°F.   Predominant algal species change, primary production is
decreased, and bottom associated organisms may be depleted or  altered
drastically in numbers and disjtribution.  Increased water temperatures
may cause aquatic plant nuisances when other environmental factors are
favorable.

Synergistic  actions   of  pollutants  are  more severe at higher water
temperatures.   Given amounts  jof  domestic  sewage,  refinery  wastes,
oils,   tars,   insecticides,  detergents,  and fertilizers more rapidly
deplete oxygen in water at higher  temperatures,  and  the  respective
toxicities are likewise increased.
                                 113
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When  water  temperatures  increase, the predominant algal species may
change from diatoms to green algae, and finally at  high  temperatures
to  blue-green  algae,  because  of species temperature preferentials.
Blue-green algae can cause serious  odor  problems.   The  number  and
distribution  of  benthic  organisms  decreases  as water temperatures
increase above 90°F, which is close to the  tolerance  limit  for  the
population.   This  could seriously affect certain fish that depend on
benthic organisms as a food source.

The cost of fish being attracted to heated water in winter months  may
be considerable, due to fish mortalities that may result when the fish
return to the cooler water.      I

Rising  temperatures  stimulate the decomposition of sludge, formation
of sludge  gas,  multiplication  [of  saprophytic  bacteria  and  fungi
(particularly  in the presence of organic wastes), and the consumption
of oxygen by putrefactive processes, thus affecting the esthetic value
of a water course.

In general, marine water temperatures do  not  change  as  rapidly  or
range  as  widely as those of freshwaters.  Marine and estuarine fish,
therefore, are less tolerant of temperature variation.  Although  this
limited  tolerance  is  greater in estuarine than in open water marine
species, temperature changes are j more  important  to  those  fish  in
estuaries  and bays than to those in open marine areas, because of the
nursery and  replenishment  functions  of ' the  estuary  that  can  be
adversely affected by extreme temperature changes.
                                 11
Chromium                         j
___                         (  ^  ,          .                .

Chromium was not found in the process waste waters generated by any of
the  Subcategories J and K facilities visited.  However, available EPA
documents indicate that chromium(will  be  present  in  process  waste
waters  when  chromic acid is used in the form-cleaning solution.  The
chromic acid is rinsed from the form and consequently enters the plant
effluent.  For plants utilizing this form-cleaning  technique,  it  is
necessary to limit the discharge jof chromium ions.

Chromium,  in its various valence] states, is hazardous to man.  It can
produce lung tumors when  inhaled  and  induces  skin  sensitizations.
Large  doses  of  chromates  have  corrosive effects on the intestinal
tract and can cause inflammation jof the kidneys.   Levels  of  chromate
ions  that  have  no  effect on man appear to be so low as to prohibit
determination to date.
The toxicity of chromium salts tcjward aquatic life varies widely  with
the species, temperature, pH, valence of the chromium, and synergistic
or  antagonistic  effects,  especially  that  of  hardness.   Fish are
relatively tolerant of chromium salts, but  fish  food  organisms  and
                             114 I
-------
 other  lower  forms of aquatic! life are extremely sensitive.   Chromium
 also inhibits the growth of algae.

 In some agricultural crops, chromium can cause reduced growth or death
 of the crop.  Adverse effects |of low  concentrations  of  chromium  on
 corn, tobacco and sugar beets have  been documented.
 Zinc   was  not  found  in  thjs  process  waste  waters   generated  by
 Subcategory J,   facilities  thiat  were  visited.    However,   available
 literature  indicates  that  zjinc  will  be  present  in Subcategory J
 process waste waters when zincj nitrate is used as a  coagulant  agent.
 However  both  concentrations j and  loadings  will  be  very  low.   The
 Subqategory J facilities visited either  did  not  use  a coagul ating
 agent   or  used  calcium  nitrate.    When  using  natural  latex,   no
 coagulating agent is apparently needed.

 Zinc in Subcategory K facility]process effluents   is  attributable  to
 zinc oxide.   The zinc appears in the foam wash waters.

 Occurring abundantly in.rocks and ores,  zinc is readily  refined  into a
 stable   pure metal and is usedjextensively for galvanizing, in alloys,
 for  electrical  purposes,  in printing plates,  for   dye-manufacture  and
 for   dyeing  processes,  and for many other industrial purposes.   Zinc
 salts are used  in paint pigments,   cosmetics,   Pharmaceuticals,   dyes,
 insecticides, and other products too numerous to  list herein.  Many of
 these  salts (e.g.,  zinc  chloride and zinc sulfate)  are  highly soluble
 in water;  hence it is to  be expected that zinc might occur   in many
 industrial  wastes.    On  the'  other  hand,   some  zinc salts   (zinc
 carbonate,  zinc oxide,  zinc  sulfide)   are  insoluble  in  water  and
 consequently it is  to be expected that  some  zinc will precipitate  and
 be removed readily in most natural waters.
                               i
 In zinc-mining  areas,  zinc has[been  found in  waters  in  concentrations
 as   high  as 5P  mg/1  and  in  effluents from metal-plating works  and
 small-arms   ammunition   plants  it   may   occur    in  significant
 concentrations,   in  most  surface and ground waters,  it is present only
 in   trace  amounts.   There is some  evidence that zinc ions are  adsorbed
 strongly and permanently  on silt,  resulting  in  inactivation  of   the
•zinc.                          !
                               |  . - .-      .•-.-.     •-•,-.
 Concentrations   of   zinc   in excess  of   5 mg/1  in  raw water  used  for
 drinking water  supplies cause  an  undesirable  taste which   persists.
 through  conventional   treatment.    Zinc  can have an adverse effect on
 man  and  animals  at high concentrations.
                               I'-?..     , , ' .   -    ;.„..=
 In soft water,  concentrations of zinc ranging from  0.1  to  1.0  mg/1
 have been reported to be  lethal! to fish.   Zinc  is thought to exert  its
 toxic  action  by  forming  .insoluble  compounds  with the mucous that
-------
          covers the gills, by damage to the gill  epithelium,  or  possibly  by
          acting  as an internal poison.  The sensitivity of fish to zinc varies
          with species, age and condition, as well  as  with  the  physical  2nd
          ™i     °haracteri stics  °£  4e «ater.  some acclimatization to Se
          SJIS2  ?  "nC " P°?sifale- - li has  also  been  observed  that  thl
          £ifr^^SnVKU80ll"g may n°* bec0l"e >PParent immediately, so that
          fish  removed  from  zinc-contaminated  to  zinc-free water rafter «-6
         :£2S ^.exposure to zinc)  may die 48 hours later.    The  presence  of
          copper  in  water  may  increase j  the  toxicity  of  zinc '
                                      °f Cc™ or har       may
          Observed  values   for  the  distribution  of zinc in ocean waters vary
          widely.   The  nancr concern with 4inc compounds  in marine waters is not
          S%S5 ^S?^°XiClty'  but ratheii of ^^ long-term sub-lethal  effects
          of  the metallic compounds  and complexes.   From  an acute  toxicity point
                           66 """6  animals Seem to  be ^e .most sensitive
                                                           for exampie-has
         SummarY 2f Sicrnificant Pollutants

         Of   the  pollutants  examined,  bnly  the  following  are  considered

                                      hSide
I            BOD
             Suspended Solids
             PH
 i           Chromium
H           Zinc
         Potentially  four of  the  five  must  be  treated  and  monitored, by
         Subcategory J facilities.  These are:                      ..  "
             BOD
             Suspended solids
             PH
             Chromium
                                                chromium will not appear in the
                                             •  '          ••••""
         Chromium was not found in the process  waste waters  of  subcateqory  K
                            116^01    °nlyf°Ur of the five parameters sLS be
             BOD
             Suspended Solids
             pH
             Zinc
                                         11
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                             SECTION VII

                   CONTROL AND TREATMENT TECHNOLOGY
Survey of Selected Plants

Several selected rubber processing  plants  were  visited  to  provide
additional  data  on  the  performance  of the waste water control and
treatment technologies used by the industry.   These  data  collection
visits encompassed analysis o4 process operations, review of water and
waste  water  management  programs,  and  evaluation  of  waste  water
treatment facilities.  The plants visited were considered to have some
exemplary  features  in  their  approach  to  waste   water   control,
treatment,  and  housekeeping! procedures.   The plant selections were
made  on  the  basis  of  consultations  with   industry   and   trade
associations,  effluent  and  [treatment  data  obtained from published
literature, EPA  records,  corps  of  Engineers  Permit  to  Discharge
Applications,  and  company historical data on waste water quality and
treatment.                    !
                              !                  "             •
As  examples  of  Subcategories  E,  F,  and  G   industries,   plants
manufacturing  molded, extruded, and fabricated products were sampled.
Compression,  transfer,  and  injection  molding   technologies   were
represented  as well as small and large-sized molded items.  The major
extruded items such as belting  and  sheeting  were  included  in  the
visits.   Diverse fabricated products such as hose and rubber footwear
as well as rare product areas]such as cement dipped goods were studied
during the plant visits.  In addition all three ranges of  plant  size
 (as  discussed  in the final paragraph of Section IV) were represented
by the data-collection plant visits.
                              I   '       -
As an example of the reclaimed rubber industry, the largest reclaiming
plant in the U.S. was visited;  *Wet digester and pan  (heater)  reclaim
processes  are  employed.   Therefore, this plant is representative of
both Subcategories H and I.  The wet digester  process  has  exemplary
features;   physical   defibeiring   is  carried  out  and  the  highly
contaminated digestion-dewatering liquor  is  recycled.   In  addition
vapor  vents  on both the wetI digester and pan processes are condensed
and decanted to recover what would otherwise be  polluting  reclaiming
process,oils.                 |
                              I.  .
Two  plants  manufacturing  l4tex  dipped  goods  were  visited.   The
products made at the two facilities include surgical gloves,  beillons,
prophylactics,   and   finger!  cots.   One  plant , employed  chemical
coagulation and settling before discharge  to  a  municipal  treatment
plant.   This  primary  treatment  produced an acceptable effluent for
discharge  to  a  municipal  treatment  system.   The  second  facility
utilized a stabilization and fettling pond system.
                              17
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 The  only  significant  latex  foam plant in the industry was sampled.
 The  treatment  facilities  used  by  this  plant   include   chemical
 coagulation  of  latex  solids aiid chemical precipitation of the zinc-
 laden foam rinse waters.-        j

 A summary of the products, processes, production capacities, and waste
 water control and  treatment  technologies  of  the  exemplary  rubber
 processing plants visited is presented in Tables 18 and 19.

 Slant A                         j

 This  plant  manufactures oil seals, 'O»  rings,  rubber-to-metal molded
 items, and miscellaneous molded rubber  products.    The  products  are
 made  from  specialty-type  rubbers  using  compression  and  transfer
 molding techniques.   Approximately 75  percent  are  nitrile  rubbers,
 about  20  percent  neoprene-typ4  rubber, and 5 percent miscellaneous
 rubbers.   The plant  has  approximately  <*6  employees  and  operates  3
   tl   -ea^«day'  six days Per w?ek*  Tne average daily consumption of
 rubber is 750 pounds,  and the weight of salable  products averages  450
 pounds per day.  The material loss is caused by  production wastage and
 rejected products.               |                                y
                                 I    •.     . *   '•.,•.•.;. - • .  , • '• ,     ,
 Approximately  95  percent  of  the  rubber stock, used in the plant is
 compounded by a supply   company]    Special  recipes  and  nonstorable
 stocks  are  mixed  at the plant|in a mixing mill.   The stock mixed in
 this mill accounts for the otherj5 percent,   when  operating, this mill
 uses about 40  gpm  of cooling water.

 The  rubber stock is  prepared for j process ing in a warm-up  mill.    From
 the  mill  the  rubber  is extruded into a basic shape.   This shape can be
 a  strip,   a   cylinder,   or  an einnulus.   The preforms for compression
 molds are made from  these basic components by cutting on a  guillotine
 ?r   *in?   slicing  on  a   modified meat slicer.  The preforms are then
 loaded into the molds.  The molds  are placed between the heated plates
 of the mold presses  and the mold  presses  are  hydraulically  closed.
 The   hydraulic fluid is oil,  at approximately 2,000  psi,  and oil leaks
 are  common.   The oil leakages are  generally  trapped  in a small oil.pit
 from which the oil is  periodically removed and reclaimed by decanting,
 drying and  filtering.  Large  oil 'spills overflow this   pit  and  enter
 the   plant  drain.  Most molds are  heated  with steam  at 350°F (125 psi)
 although  a  few older molds  are generally  slabs of  rubber  stock  which
 afe  ,_loaded into the  transfer section  of mold.  The mold is closed in
 the  hydraulic  press.   The rubber 'wastage  on  a transfer-molded item  is
 higher  than   for  compression  njolding but  the  labor  requirements are
The molded items  are  deflashed
in  a  wheelabrator  machine.   This
                       	— — — | «.*.  M  w***w^^«*Aj.i. c*i,WJ_  lUCLWJU.J.li^« '  i AiJLo
£feezf?  the item with liquid nitrogen, making the rubber brittle, and
then blasts it with small steel shot.  T!he rubber fines and  shot  are
separated  and the fines and dustl are collected in a bag collector and
                              118 I
-------
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-------
 drummed.   The
 thousandths  of
                steel  shot  range  in  size  from  seven  to  twelve-
                 an  inch.   In cases where the shot would blind small
 crevices of the  molded   items,  manual  deflashing  is  carried  out.
 Manual  deflashing  consists  of  spinning  the  item  on  a chuck and
 grinding off the flash with a fine  sandstone.

 The molded products are inspected,  packaged  and  shipped.   Rejected
 items are removed as solid waste.
 Metal   parts   for   rubber
                             j  bonding   are   first   degreased  with
perchloroethylene vapor.  The]waste, grease-laden solvent, is  drummed
and  removed  as solid waste.|  After degreasing the bonding surface is
sand blasted in a sand blasting drum to impart a rough  surface.   The
prepared  bonding  surface  is  painted  with  a bonding agent (rubber
cement)  and the preform is attached.  The metal preform item is molded
in a similar manner to the all-rubber items.
                             i
Occasionally the molds require cleaning.  This is carried out by a dry
honing process which consists!of blasting the molds  with  fine  glass
beads.                       j                                         .

Haste  waters  are  generated jby:  cooling waters from the compounding
mill, the warm-up mill, the  ^xtruder  and  the  nitrogen  compressor,
blowdown  from  the  boiler  (approxiately twice a day, 5 gallons each
time) , and regeneration wastes from the boiler  feed  water  deionizer
((approximately  8  Ibs sodium chloride per day) .  The steam condensate
recycle rate is high, approximating 100 percent.

Contaminants, oil  and  grease,  and  minor  quantities  of  suspended
solids,   enter these utility streams at unprotected floor drains.  The
raw plant effluent, includingjutility streams, has oil  concentrations
on the order of HO mg/1 and negligible suspended solids.
 This  plant manufactures electrical gloves and shoulder-length sleeves
 via a dipping process in solvent-based rubber cement.   The  principal
 raw  material is natural rubber, although EPDM rubber gloves are being
 developed.  The solvent is a  j naphtha  type  compound.   The  material
 consumptions  average  1,100  |pounds  of  rubber  and 1,100 gallons of
 solvent per day.  Each pair of gloves requires approximately one pound
 of rubber.  The sleeves require more rubber.  The  plant  operates  24
 hours per day, 7 days a week.

 The  rubber,  pigments,  and vulcanizing agents are compounded on a 2-
 roller mill and are sheeted out to approximately one-half of . an  inch
 in  thickness.  The mill uses i once-through cooling water.  The sheeted
 rubber is fed into a guillotine where it is  chopped  into  three-inch
• squares, which are weighed intto a container.
                               ! 121
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The  rubber  is transported to the cement mixing room where the rubber
is dissolved in solvent in a blend tank.  The mixed rubber  cement  is
transferred  from  the blend tank I to a storage tank where it is stored
before the dipping operation.   Cements  with  different  recipes  eind
colors  have  their  own storage tank systems.  The naphtha solvent is
pumped from butside tanks to the blend tank  via  two  solvent  pumps.
Solvent   spills  are  very  infrequent  because  of  fire  protection
requirements.  The mixing room is'fitted with an automatic fire system
which is designed to shutdown the I pumps, close  the  doors  of  mixing
room,, and fill the room with carbon dioxide gas to extinguish a fire.

The  gloves are dipped onto glazed porcelain forms in a cement dipping
room-  The forms are held on a rack by their bases and dipped  betwssen
20 and 30 times to build up the glove thickness.  Each rubber layer is
allowed  to drip-dry between dips 1   The total dipping-drying operation
takes about a8 hours.  The temperature and humidity of the air in  the
drying room is controlled by an air quality coiftrol system.  Exhausted
air  is  used  to heat incoming air.  No air pollution control devices
are believed necessary.  The air  quality  control  system  discharges
condensation  at  times  when the air requires dehumidification.  This
condensation is pure water.      j

After drying, the base of the gio\[e is trimmed by a cutting wheel  sind
the cuff bead is formed by rolling up the cuff.  Labels indicating the
brand and size are attached to the glove cuffs with rubber cement.

The  gloves still on~the forms are loaded into an open steam autoclave
for vulcanization.  The forms areiallowed to adjust  to  the  residual
temperature  of the autoclave before the steam is applied.  The gloves
are cured with 35 psig steam (temperature 280°F) for 40 minutes.   The
forms  plus gloves are removed from the autoclave and allowed to cool.
During the curing operation, the steam condensate that accumulates  in
the  autoclave is discharged for seven seconds every two minutes under
pressure to the plant drain.  The|condensate picks  up  organics  from
the  curing  gloves.  The COD of this steam is approximately 800 mg/1.
The flow, however, is extremely low, about 3 gph on average.

When partly cooled, the gloves are dipped in a talc slurry and allowed
to dry.  The talc slurry is a closed system.  Makeup  talc  and  water
are  added  to  the  slurry  dip jtank.   The  dry gloves are stripped
manually from the molds 'and placed in a tumbler with a small amount of
talc powder to coat the inside ofjthe gloves.
                                 !             •  '  '
The procelain molds are cleaned periodically by manual scrubbing.  The
scrubbing waste water and rinse waters are  containerized  and  hauled
from the plant by contract haulers.

The  gloves  are  visually inspected for flaws.  Gloves which pass the
visual inspection are tested for [their  electrical  resistance  in  a
water  tank.   The  tank  overflow, low in flow and uncontaminated, is
                            122
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discharged to the  plant  effluent.   Gloves  which  fail  the  visual
inspection or the resistance test are sold as industrial gloves.

The  green  bladders  are  cured in steam heated stand-presses.   These
presses are mechanically closed and the whole bladder building area is
wdry" and oil free.  Steam cohdensate from the  presses  is  recycled.
Metal  parts  for  molding tojthe bladders are first degreased using a
closed trichlorpethylene system, sandblasted, and sprayed with  rubber
cement as a bonding agent.   j
                             i
Plant C                      j

This  plant  produces  molded'  rubber  grips  for  golf  clubs,  tennis
rackets, baseball bats and tools.  Another major type  of  product  is
bladders  for  air-activated brakes and clutches.  The types of  rubber
used  are  natural  rubber  (approximately  75  percent)  and  various
synthetic rubber (about 25 percent).  The daily quantity of compounded
rubber  stock  used  to manufacture the grips is 17,000 pounds,  and to
build the bladders is 2,240 pounds.

The rubber stock is compounded in a separate building.  Stock is  also
prepared  for  a  sister plani in another location which does not have
its own compounding facilitiei.  The grips require  stock  of  various
colors,  including  black.   Carbon  black  is not added at the plant;
instead, black master batch rubber is used.   The  bladders  are  made
solely from black rubber.  The compounding facilities consist of a No.
3  Banbury  mixer,  two  intermediary  or  storage mills, a 4 roll, Z-
calender mill,  a  calendered'  stock  sprayer  cooling  tank,  a  zinc
stearate  dip  tank,  and  a stock drying tower.  In addition, a small
calender is used to prepare s^ock for  the  pneumatic  bladders.   All
cooling  water,  with  the^ exception  of  the  spray cooling tank, is
provided by a closed loop chilled water system (water at  t6°F).   The
spray  cooling  water is discharged untreated to the main plant sewer.
The dust collection device for the Banbury mixer is  a  wet  scrubbing
roto-clone.  Because of poor performance and maintenance problems, the
roto-clone  is not operated and is to be replaced with a bag collector
device.                      !

The rubber grips are molded b^ compression,  transfer,  and  injection
molding  equipment.   The injection mold extruder is cooled by its own
closed loop chilled water system.  The presses for the compression and
transfer molds are hydraulic oil activated.  Oil leaks occur  and  are
soaked  up with absorbent granules.  No open floor drains exist in the
molding area.                j

The molded rubber grips are -.deflashed by hand using a  trimming  knife
before  painting and final preparation.  The grips are dipped in paint
and hung to dry.  Paint drippings and spills are  contained  since  no
floor  drains  exist  -in  this area.  The paints are mixed in a closed
room to contain solvent odorsi   There are no floor drains in the paint
                            "I   •.••••••••-•
                             |123
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I
                                  I   •,'-..-

mixing area.  There are potential air pollution problems in this area.
A control system has yet to be selected.

After painting, the grips are buffed to impart smoothness  and  remove
the last traces of the flash.  Dry; bag collectors are used to trap the
airborne  buffing  dusts.   The  mplds  are  periodically  cleaned  by
blasting with glass beads in a closed hood.
                                  i ,                •   .   ,.
The pneumatic bladders are built oh  building  machines  in  a  manner
similar to tire manufacture.  Cord! fabric is purchased from an outside
supplier.                        • J

The  green  bladders  are  cured in steam heated stand-presses.  These
presses are mechanically closed and the whole bladder building area is
"dry" and oil free.  Steam condensate from the  presses  is  recycled.
Metal  parts  for  molding to the bladders are first"degreased using a
closed trichlorqethylene system, sandblasted, and sprayed with  rubber
cement as a bonding agent.        i

Approximately 80 percent of the steam used in the plant is recycled to
the  boiler  as  condensate.  The boiler feed water is not softened to
demineralized.  Instead, treatmentjagents are added to the feed  water
to  eliminate  scale build up.  The only process-associated discharges
to the plant sewer are cooling water for the service  air  compressors
and  cooling  water  for  the  hydraulic oil pumps, in addition to the
calendered stock spray cooling watfer.  The overflow from  the  plant's
septic tank systems is routed throiigh the main plant sewer.

Extruded  oil  used  in  the mill room and machinery oil stored in the
compressor area have  on  occasion!  entered  the  effluent  via  floor
drains.   It  is  the company's belief that these drains can be closed
and the oil involved stored elsewhere..

The plant's effluent has good COD j (50  mg/1),  suspended  solids  (13
mg/1)   and  oil  (7  mg/1)  levels, j  It is believed that the oil can be
further reduced with good housekeeping and the blocking  of  offending
floor drains.                     I
        This  plant manufactures  several types  of reinforced hose.  The outside
        diameters   of   the  hoses   range   from  approximately  3/4 inch  to  six
        inches.  Hoses are made  on  both rigid   and   flexible  mandrels.   Most
        sizes  of   hose  can  be made  injlengths  up to about 100 meters.  In
        addition,  small bore hose can be produced in continuous lengths.  Hose
        is  reinforced  with yarn  and wire   using  braided  and  spiral  winding
        methods.   Vulcanization  is  carriedjout by both cloth wrapped and lead-
        sheathed techniques.   The plant consumes appoximately 20,000 pounds of
        raw  materials  each  day.  it operates 24  hours per day for five days
        each  week  and  employs 530 people.  |The plant is in a rural area  with a
                                    124
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            total area of 120 acres, 7.3 ajcres of
            plant area.
                                        which  consist  of  the  roofed
            The  plant  water  is  supplied  by  3  wells owned by the plant.  The
            capacities of the wells are 50:0, 250 and 250 gpm,  respectively.   The
            water  from the 500-gpm well ils chlorinated for domestic, sanitary and
            process usage in order to minimize the activity of ferro-bacteria.
                                          I
(**•«
Rubber  stock is prepared in  tjhe   compounding  area.    The  recipe  is
varied   to  suit the particular service requirements  of the hose.   The
rubber  ingredients are mixed in a Banbury mixer and sheeted out on  a
roll mill.  The sheet rubber iis dipped in soapstone slurry and hung to
drip and dry.   An open drain Ibeneath the soapstone drip area collects
soapstone drippings which are jdischarged to the plant's final outfall.
In  addition, the cooling water!  from the mills is  discharged  into  an
open drain  which can readily  be fitted with a collar, or the opening
can be  completely sealed to prevent the entry of oil  and grease 'to the
' drain.               '        - |        ••   • . •
                              i    - •  "               .
The tube component of the hose!  is extruded and cooled in an open  tank
by  direct contact with cooling  water.  From the cooling tank, the  tube
is   passed  through  a tank of  anti-tack agent ("Acrawax") .  Soapstone
solution is not used for application because its anti-tack property is
more permanent and would adverjsely affect the future   bonding  of   the
tube to  the  other  componenits   of  the hose. -The  overflow from the
cooling tank and drippings frojm the anti-tack system  are discharged to
the plant's final outfall.  The floor  drain  to  which  the  overflow
cooling  water  is  discharged  could  be  equipped  with  a collar or
            completely sealed.
            in a helix.
                     The extruded and cooled tube is coiled on  a  form
                              i
            Hose tube that requires rigid mandrel support is unwound from its coil
            and  pulled  onto  the rod-like mandrel in lengths of approximately  50
            meters.  Tube to be supported Jon flexible mandrels  is  extruded  onto
            the  rubber-  or  plastic-coated  .mandrel  at the extruder.  A  release
            agent is sprayed "between  the | tube  and  the  mandrel  to  facilitate
            subsequent   removal   of  the;  mandrel.   Some  small  bore  hose   is
            sufficiently rigid not to require a mandrel.                    '
                                          I                    -
            The hose tube is braided or splirally wound with  yarn  or  wire.   The
            yarn  and  wire  are manufactured by supply companies and are received
            ready for use.  The "reinforcing" operations are "dry"  and  no floor
            drains  exist  in  this  area.]   The  outer cover is extruded into the
            reinforced hose before curing.l
                                          i    .     •   -       •    •"•'•',
            Shorter lengths of hose are sh'eathed with lead in a lead  press.   The
            lead  sheath  is  cooled  dire|ctly  with  water.  The sheathed  hose  is
            placed in a long autoclave which is heated directly with steam.  After
            curing, the lead sheath is stripped JErom the  hose  and  re-cast  into
            billets  to  feed  the lead press.  The cured hose is removed from the
-------
mandrel by water or air  pressure,  inspected, and coiled  for  shipment.
Larger  sizes  of hose  are  tape-wrapped  and charged into  a  direct-steam
heated autoclave.  After curing  the  tape is removed from the hose  and
the  mandrel   removed  by water or  air pressure or a mechanical  pulling
technique.  The condensate from  the  lead-sheathed  curing autoclaves
contains  lead  (70 mg/1)  and is discharged directly.

Cooling   waters  from  the  millsJ  tube  extruders,  and  lead  cooling
processes are  discharged via sumpsj to the final outfall.   Periodically
the  sumps are  cleaned  of  accumulated oils  and  solids.   The  air
compressor  condensate  passes   through an oil trap drum.  The  drum is
periodically skimmed of  oil.  The  icombined waste waters  flow over a V-
notch weir into a small  creek to tihe river.
               .  •     -             !                      •
An outside drum storage  area contributes to the  oil  in  the   plant's
waste water during stcrms.   This area is unroofed and is used to store
new,  partly full, and empty drums' of various oils and chemicals.  The
storm water passes through a sump  before its discharge   to the final
outfall but the sump is  not regulajrly cleaned and oil seepage occurs.
The  plant's  combined  effluent  lhas  the following quality:  COD, 20
mg/1; suspended solids, approximately 1 mg/1; and oil and grease, less
than 1 mg/1.                      !

Duplicate samples analyzed by Plant D yield a different description of
the, effluent quality: COD, 28
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The compounded rubber stock is prepared for processing on four warm-up
mills.   Rubber from these mills is formed into sheets in an extruder-
calender machine.  The tempera'tures of the roller mills and  extruder-
calender  are  controlled by recirculated cooling water and hydrotherm
cooling systems.  The sheeted) rubber  is  cooled  in  a  water  spray
cooling  tank.   The  contactjcooling water overflows and is reused in
the plant's main recirculated jcooling, water  system.   After  cooling
the  sheeted rubber is dipped Jin soapstone solution to prevent it from
sticking together during storage.  Curbing and a floor sump have  been
installed  in the soapstone dip area to contain accidental spills, and
overflows.  The sump is emptied into a portable tank and removed by  a
private hauler.               j

The  dipped  sheet rubber is passed over air vents to dry, and is then
rolled up into large rolls.  The sheeting operation described above is
performed eight hours each day, five days  per  week;  it  uses  60-70
percent of the cooling water Circulated through the plant.

Once  sheeted,  the rubber is Isold as uncured or cured sheeted rubber,
or conveyor belting.

Curing of sheeted materials is! performed in presses, rotacures, or hot
air curing ovens.  The rotacufe system employs a combination of steam,
cooling water, and electric  lieaters  to  cure  sheeted  rubber  under
prescribed conditions.  Both -tihe steam and cooling water are recycled.
Presses  employ  steam  and  a  hydrotherm  cooling system to cure the
sheet.  The third system is a gas fired hot air cure.  This  technique
does not require steam or cooling water.         .

In addition to the production |of sheeted rubber, the plant also builds
the  body  plies,  or  carcasses,  used  to  make conventional fabric-
reinforced  conveyor  belting.   Fabric,  which   has   already   been
frictioned with rubber, is shipped to the plant,.  This material, which
is  single  ply and has a maximum width of approximately 55 inches, is
used to build carcasses of multiple ply thicknesses and various widths
up to approximately 128 inches.  Once built, this belting is rolled in
fabric cloth and sent to another plant to  have  an  upper  and  lower
layer of rubber applied to thej fabric,  completed belts are frequently
returned to the plant for curing.
                              I         '               :
Waste  waters  are  generated jby the cooling system overflows, zeolite
softener  regeneration  wastes,   boiler   blowdown,   plant   runoff,
hydrotherm systems, air conditioning systems, and domestic sources.

The  principal  waste  water  jproblems at the plant originate with the
hydraulic oil systems for the I curing presses.  Oil leaks from the  oil
systems  are  frequent.   Curbing and oil sumps have been installed to
contain such leaks.  Periodically the collected oil  is  removed  from
the  sumps  and  drummed prior to disposal.  The oil leakages from the
hydraulic oil systems have in the past been so severe and  uncontained
                                127
-------
            g*ound  beneath  the  tiant  contains large amounts of oil.
 described above; ^"p^ntls ^X/^dSS^^SSS

 nlllL WatHKS-   "  Sh°Uld  be  ^oted'  however,  SS94ifplE?
 neither rubber compounding nor process oil storage  '


 Plant F

 This plant manufactures rubber  pipe  seals
 rubber-to-metal molded items.  — '   '
&
<
                                        .

 oK     comP°unded ^ a B^nbury mill.  Depending on the amount
 of   stock  being  processed,   botli nonreactive and reactive stocks are
 compounded.   During  normal   operations,  however,   the   stock   Is
 compounded    onl   once  (reactive  stock)   with  all  the  SoSpound"
                       a"9fints' adde<3 at the same time.  The material is

                                  ^^~' air ^ied' «*  ^-^  "
                                  .-|
 Weather  stripping,   pipe  seals,  j and  molding  plugs  are  formed bv
                            r  10ng  Kreled ext?udlrs?  Short
          do                    StH±P feed mills'  whereas lon
               ?:       extruders   are  temperature  controlled;   both
            cooi:Ln?   water are used.   The extruded items are cooled,
       *         P   Ced ^ autoclah Fans in preparation  for  curing
 Extruded items are cured  in autoclkves with 100 psi steam.      *-""•"?•

           the  cavities  of
           Before curing, the
       to ensure proper release frjam the~mold!
                                  I                              .  • .
The  ends  of pipe seal rubber are: cemented together to form the  large
         ui! PXPK s?als'  The operation is carried out in  an  electric
         wnen  bonding  rubber  to'.metal, the metal na-r-h mne-f- 4^*-o4- ^^«
degreased,  using  trichloroethylen4  in 'a  clSsS  lysteT,  and   then
                                128
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 sprayed  with an adhesive.   The rubber is transfer-molded to  the metal
 part.

 Waste  waters generated at this! plant include  boiler  blowdown,   cooling
-tower    and  chiller   water  overflow,  once   through  cooling  water,
 leakages, from the .various  hyjdraulic  and curing  oil  systems,   and
 spillages and drippings of lubjricating solutions.

 The  greatest problem currently facing the company is storm runoff.  A
 recent large spillage of oil cbnvinced company officials that  control
 and  treatment  of this type problem was a necessity.   Sewer  lines  are
 still  coated with oil from the spill.   To control  this  problem,,   two
 gravity  separators   collect  all   water  leaving  the plant  including
 runoff.  Oil storage  pumping stations  are covered.    Drip  pans   are
 provided for oil transfer lines.

 Steam'condensate from the autoclaves flows into a  final holding lagoon
 and  is  not discharged.  Boiler treatment and blowdown wastes  and  one
 group  of roof drains  flow into a detention pond  to  settle  oil   and
 solids.  From the detention pond,  the water is siphoned from  below  the
 surface  and flows to  a separator where any residual  oil is removed.

 The  resultant  effluent  concentrations  are  approximately: COD,  100
 mg/1;  suspended solids, H'O mg/ls and oil, 3 mg/I.

 Plant  G            .            j
                               I
 This plant manufactures braided and spirally  wound,  reinforced  rubber
 hose as  well as plastic-based hose.   Both metal and  fabric reinforcing
 components  are  used.    Tota^  raw  material  consumption for jrubber
 products is approximately 162,500  pounds per  day.  The plant  operates
 24 hours per day, 5 days per week.                              '

 Three  different production processes are employed.   Industrial  hose is
 produced by  compounding,   extruding,  and  pan  curing.   Hose, which
 requires curing inside a mold,j is  produced by compounding, extruding,
 encasing hose  in  lead,  and  curing.   Preformed hose is produced by
 compounding, extruding, forming, and curing.
                               i     "      -     •  •
 All rubber and compounds are mixed in one of  four  Banbury mills.    The
 compounded  material   is  dropped  from the Banbury where it is  sheeted
 out, dipped in a recirculated soapstone solution,  air dried,  and piled
 on skids to await further processing.

 To make  the hose, compounded rubber is extruded into  a  tube.   Both
 long   and  short barreled extruders are employed at  this plant.  Short
 barreled extrudes require warm up  and strip feed mills,   whereas  long
 barreled extruders   do  not. !  The tubing is cooled,  dipped  in a zinc
 stearate lubricating  solution 'and  placed in a temporary storage.
                              129
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         Reinforcing material is applied to the outside of the tube by braiding
         or winding machines.  No water is used in  this  area.   Finally,  the
         outer covering is extruded onto £he reinforced rubber tubing.
         Lead  sheathing  can  be  extruded  onto the hose in a solid or molten
         state.  The lead covered hose is j wrapped onto large spools.  The lead-
         sheathed hose is filled with watfer to apply pressure on the inside  of
         the hose before it is cured in steam heated autoclaves.  After curing,
         the  lead  covered  hose  is  copied  and the lead covering is removed
         mechanically and recycled to the  sheathing  process.   The  water  is
         released  from  the  inside  of
i
the  hcse.  The hose is hydraulically
           shipment.   The  hydraulic
tested with water before final s borage and
test water is discharged.

Industrial  hose  which  does  njot  require molding is pan cured.  The
stock is placed in pans and curejd in autoclaves.   Preformed  hose  is
made  from uncured or semicured jhose which is Cut to length, placed on
a form to give it the proper shape, and cured in autoclaves.
                                i    •'-.-.••
Waste waters from this  plant  arise  from  the  use  of  water  as  a
lubricant,  spillages  of  other!  lubricating  or anti-tack solutions,
condensate from autoclaves, hydraulic  testing  water,  pressure-water
for  the  curing  operation,  bojiler  blowdown, softener backwash, and
cooling system overflows.  No stleam condensate is recycled.

A municipal system receives all  the  waste  waters  from  this  plant
operation.  No pretreatment of waste is practiced.

The  effluent  quality  is compalrable to other plants in this industry
group and is acceptable  for  publicly  owned  treatment  works.   The
effluent  levels  are  approximately:   COD,  300  mg/1; BOD, 30 mg/1;
suspended solids, 40 mg/1; and oil, 5 mg/1.
         This plant produces canvas footw,ear,  cement  dipped  boots,  and  foam
         rubber  for  carpet  underlay arid  shoe  innersoles.  Daily raw material
         consumption amounts to approximately  265,000 Ibs  per  day  of  rubber
         compounds.                   .

         canvas  shoes   are  the result.of  many  different production operations
         including  compounding  of   rubber stocks,  molding  of  the   soles,
         extrusion   of  the  other   various   rubber  components,  cutting   and
         fabricating of  canvas parts, construction of all these items into   the
         final product,  and curing of the final  product.

         The  rubber  used  in this plantl is compounded with other chemicals in
         six Banburys and sheeted out injmills.   The  compounded  sheeted stock
         is  cooled  on  six cooling conveyers  employing three different  cooling
         techniques?   a water  spray,  a  cooling  water  tank,    and   water
-------
 evaporation.   Three cooling colnveyers employ a water spray against  the
 bottom of the conveyer belt carrying the rubber stock.   On two  coolina
 conveyers  the  rubber  is  cqmpletely  immersed  in water.  The  final
 system employs a spray directljy onto the rubber.  Evaporation of  this
 water  supplies the bulk of the cooling.  After cooling  by each of  the
 three techniques, the rubber is rolled onto large rolls.
                                  - .  -    -L
 The  innersoles of the shoes are  cut  with  dies  from   sponge  rubber
 sheets.     The  sponge  rubber  sheet  is  prepared   by  extrudir-   —
 calendering rubber stock,  containing blowing agents,  into  sheets,
 sheets are continuously cured in presses.
The
                              I
The  soles are  either  cut  from juncured  rubber   sheets,  or  formed  in
compression or injection  moldsi.  The technique  employed depends on the
final  product  and  the technology available.

Compression molding technology] is older and requires more manual labor
than  the  completely automated injection technique.  Its advantage is
in the ability to  mold many  different  colors  simultaneously.   oil
supplies  the   hydraulic  pressure  for  both molding techniques.  The
curing presses are heated elecjtrically.

After  curing the molded soles are buffed to remove the flash.  A  coat
of latex is applied to the sole after which it  is dried in an electric
oven.

Canvas  uppers for   shoes  arfe  made  from two or three ply material.
Canvas material arrives at the plant as single  ply sheets  in  various
colors.   Latex  is   applied to the sheets; the sheets are then pulled
together and passed over  steam heated drums.  The sheets  are  stacked
and  then  cut to the   proper dimensions using  a die and press.  The
various pieces composing  the canvas portion of  the shoe  are  stitched
together in making lines.                 -.

The  shoe is fabricated from the various components on a form called a
last.  The canvas  top  is  cemented at its edges  and  placed  over  the
last.   The  innersole  is  then  applied.  Before the toe pieces, the
boxing, and the outer  sole are|applied, the bottom  of  the  innersole
and  canvas  is dipped in a latex solution.  The  latex is used to hold
the entire shoe together.  Next the sole, toe   and  heel  pieces,  and
boxing  are  applied.    The  finished  uncured  shoes are inspected and
placed on- curing racks.  The shoes  are  cured  in  autoclaves  in  an
ammonia  atmosphere.   Approximately  10  Ibs  of  ammonia is used per
autoclave per cure.  At the end of the curing process,   the  autoclave
is  vented  to  the  atmosphere.   The need to collect and control the
ammonia contained in the autoclave ventings is being investigated.

Cement dipped boots involve a  slightly  different  building  process.
The  pieces  of  fabric forming the carcass of the boot are applied to
                              131
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                                 I
                                 I
forms which are dipped in a rubber cement solution, dried, cured,  and
finally packaged.

Process  waste  waters  from this plant consist .of latex tank cleaning
waste  waters,  oil  dripping  and  leakage  from   heavy   processing
machinery,  and  discharges from wet dust collectors.  Waste latex, or
latex remaining in drums that can no longer be used, is  removed  from
the plant by a private contractor.  Latex rinse waters, used to remove
residual quantities from the latex drums, are coagulated with ammonium
alum and settled out in a retaining basin.  Clarified water is allowed
to overflow to the river.  Coagulated rubber is removed from the basin
whenever  necessary.   The  washing  operation  is periodic, occurring
approximately 10 to 12 times per'24-hour  day.   Discharges  from  the
basin  occur  for  a  total of approximately one hour each day.  Plant
personnel are considering modifying the system by adding mixers to the
basin.  There is currently insufficient mixing in the basin and  large
quantities  of  latex  remain uncoagulated and leave the basin via the
overflow.  This latex eventually!coagulates  in  the  overflow  drains
causing them to clog periodically with solids.

Drippings  from  open  gears and]leakages from motor and mill bearings
cause the spillage and leakage o£ oil and water to accumulate  in  the
mill  and heavy machinery basinsi  The plant has installed two systems
to cope with these problems.  Motor areas are diked and equipped  with
a  300-gallon  oil  collection  sump.   Mill  basin  drains  have been
intercepted so that leakages" that enter these drains flow via a trough
into a holding tank.  Oil is removed from  the  tank  by  a  stainless
steel  belt.   Plant personnel estimate the retention time in the tank
to be 72 hours.  When operating, | the unit has an overflow rate of  1-2
gpm.   Oil  picked up by the belt passes into a waste oil storage tank
which is periodically emptied and the waste oil drummed.

Each Banbury line is equipped with a wet dust collector.  In addition,
two wet  collectors  control  particulate  pollution  in  the  buffing
operation  by  collecting sole flash.  Flow from these collectors goes
untreated to the outfall.        j

The plant effluent quality is approximately:  COD,  76  mg/1;  BOD4,  6
mg/1; suspended solids, 29 mg/1; and oil, 7 mg/1.

Plant I                          \

This   plant  manufactures  reclaimed  rubber  from  whole  tires  and
miscellaneous rubber scrap.  Dai.ly raw material  consumption  includes
175,000  Ibs of whole tires  (apprbximately 8,750 tires) and 127,000 Ibs
of  miscellaneous  scrap,  the   bulk  of  which is inner tubes.  Total
reclaim  production is currently  271,000  Ibs  per  day.   Two  reclaim
processes  are  employed,  one for tires based on the conventional wet
digestion process, and a second  process used primarily for scrap inner
tubes, called pan or heater procjess.
                             132
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In the digester process, whole tires are  brought  to  the  plant  and
stored  in open areas.  Plant [personnel manually separate steel belted
and studded snow tires  from  jother  conventional  tires.  . Currently,
tires  containing  steel  (othe'r than bead wire)  cannot be processed by
this plant and are sent to dumps.  Tires to be  processed  are  passed
through  a  magnetic  sensing {device which removes any steel belted or
studded tires not previously removed.

Cracker mills grind and break jup the whole tire.  The ground tires are
screened and oversized particles recycled to  the  mills.   After  the
first milling, an operator removes large sections of the bead wire.  A
magnetic  separator  removes  the  smaller sections of bead wire which
pass through the screens with the ground  rubber.   The  particles  of
rubber  which still contain fiber from the cords and belts are further
grourid in stoners  (fine grinding equipment)  and  hammer  mills.   The
additional  grinding  facilitates  the  removal  of  the fibers by air
separation techniques.  Separated fiber is baled and sent to  landfill
sites.

A  final  grinding  operation, reduces  the rubber particle size to 20
mesh.  This grinding is necessary for the removal of the final  traces
of  fiber  from  the  rubber  jproduct.  The reduced particle size also
reduces the amount of oil necessary to devulcanize the rubber  in  the
digestion step.               i

The fine, fiber-free particles are mixed with oil, water and chemicals
 (typically a calcium-based or!formaldehyde digestion solution) and fed
to  a digester where the rubber is devulcanized.  The digestion liquor
is heated with steam injection.  From  the  digesters,  the  resultant
slurry passes to a blowdown t^nk.  Quench.or cooling water is added to
the  slurry  in the blowdown t-ank.  From the blowdown tank, the rubber
slurry passes to a holding  tank,  where  additional  water  is "added
before  dewatering on a screerji and finally in a dewatering press.  The
dewatered rubber is dried in screw dryers  using  recirculated  steam.
The  liquor  from  the screen|and press pass through a 200-mesh screen
where fine rubber  particles are recovered.  The dewatering  liquor  is
recycled  to the digesters,  \tapors from the blowdown tank are trapped
and condensed in a barometricicondenser.  Vapors from the  dryers  are
similarly  condensed.  Oils are separated from the condensed vapors in
a decant tank and  are returned to the digestion stage where  they  are
reused.

The recycle system for the dewatering liquor and the reclaimed process
oils  is  shown  in Figure 9.• The waste overflow from the decanter is.
approximately one-third of the total of the  waste  dewatering   liquor
plus the vapor condensate without .the recycle system.              '

The  dried devulcanized rubber is mixed with other compounds including
carbon black and oil.  The mining takes place in  an  internal  mixer-
extruder,   compound  usage  follows  a specific recipe  related to the
                                133
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 U
 o
m
IU
O
a:
O
IU
IU
Of

O
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end-product use qf the reclaim.  Finally  the
milled into sheets to form the final product.
                                              compounded  reclaim  is
The  pan  or  heater  process,! which is used for miscellaneous rubber
scrap but primarily for inner tubes, differs from  the  wet  digestion
process  described  above  in  \that  no  fiber separation equipment is
needed and devulcanization of the rubber is  carried  out  via  a  dry
process.    .  -    ••'••'

Operators  remove  metal,  such  as  inner tube valves, from the scrap
rubber.  Conveyors carry the metal-free rubber to a cracker mill where
it is ground  and screened.  Th£ rubber particles are  mixed  with  oil
and  other  chemicals,  placed! in  bins,  and devulcanized in a large
horizontal heater.  After devuicanization, the rubber is  milled  into
sheets to form the final product.

Process  waste  waters  from  jbhe  wet digester process arise from the
dewatering process and the various vapor condensers  in  the  digester
process  area.  Discharge of the waste water from the dewatering press
has been eliminated in the pasj: year by recycle of the  water  to  the
digestion  stage.  Oils condensed from the vapor streams are separated
from the water in a decant tank and fed back to the  digester.   Water
from  the  decant  tank is recycled to the digestion makeup stage when
possible or discharged as a waiste water.  Process  waste  waters  from
the  pan  devulcanizer process) are caused by the condensation of vapor
streams.  These are combined with digester vapor streams and  decanted
together with the digester strjeam.  The reclaimed oils are recycled to
the wet digestion process.

The process waste waters which cannot be recycled are discharged.  The
resulting  plant  effluent  qujality  is approximately:  COD, 110 mg/1;
suspended solids, 50 mg/1; and) oil 10 mg/1.  It is believed that these
waste waters  would be readily  Created in a municipal sewage  treatment
system.
                                                  Finger cots  are also
This  plant produces balloons and prophylactics.
produced, but not on a continuous basis.  The plant is  located  in  a
rural  area and employs approximately 50 people.
                                                  Natural  latex is the
 primary raw material for all  d'ipped items.  No  other  types   of   latex
 are  consumed.   Approximately 2,650 Ibs  latex is used to produce 3,800
 gross of prophylactics per day;   10,170 gross of  toy  balloon  are
 likewise produced from 6,810  l{bs  of latex.  Because of  the proprietary
 nature  of  the production equipment and the highly competitive  nature
 of  the  operation,   inspection  of  the processing  lines   was   not
 permitted.

 The  natural latex arrives by itank car and  is pumped to holding  tanks.
 The latex recipe is compounded! in a water-cooled tank from which it is
                                135
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pumped into drums together with vjarying
makeup, water depending on the end-use.
used  as,  makeup  for
balloon dip tanks.
the  four
                  quantities  pf  dilution,  or
                  This drummed latex mixture is
prophylatic dip tanks and the twelve
Clean molds are coated with latex; in these dip tanks.  The  tanks  are
cooled  with  recirculated cooling water.  The latex-covered molds are
passed through a hot air dryer ov'en to strenthen the  rubber  coating.
This  process  is  repeated in a jsecond dip tank and dryer train.  The
latex-covered molds are now cured' in air-heated curing  ovens.   Steam
is used to heat both the drying and curing air.

After  curing,  the dipped goods ,are sterilized in a 200°F water bath.
Steam injection is used to heat the water bath.  The overflow from the
sterilization bath is negligible isince the water loss from  the  baths
by carryover on the molds is approximately equal to the steam makeup.

The  dipped  items  are coated with a talc and stripped from the mold.
The products are finally inspected, packaged, and shipped.
                                 i
                                 I
Stripped of the cured product, thje molds are cleaned and rinsed before
being returned to the dip tanks. ! The cleaner  tanks  contain  a  one-
percent  solution  of  Oakite  Ru'stripper  in  water.  There is little
overflow from the cleaning tank. ] The rinse tank is raw water  but  it
does  pick  up  talc  and  cleaning  agent  from  the mold.  The rinse
overflow waste water is therefore! contaminated with surfactants.

Process waste waters arise from the small overflow from the steriliser
tanks, minor discharges from the mold  cleaning  tank,  and  from  the
rinse water overflow.  As mentioned earlier, the first two sources are
negligible.   All  process  waste!  waters  and the boiler blowdown are
directed to holding lagoons.  The] primary constituents of the  process
waste  waters  are  the talc and surfactants removed from the molds in
the rinsing process.                      .
                           •     , I
The waste water treatment facilities in this plant  consist  of  three
lagoons,  one  holding  lagoon anjd two detention lagoons.  The holding
lagoon is used to contain  all  wjashdown  and  cleaning  waters.   The
detention  lagoons  treat  the rinse water and blowdown for removal of
solids.   In  addition,  the  latjex  tanks  were  rinsed  with   small
quantities of water and wiped clean with rags.

The  plant  effluent contains:  cbo, 120 mg/1; BOD, HO mg/1; suspended
solids, 85 mg/1; and oil H mg/1. | The effluent  surfactants  level  is
negligible (less than 1 mg/1).

Plant K

This  plant  produces  compressioh  molded sundries, such as hot water
bottles, hygiene syringes and bulbs, and pharmaceutical  items.    Also
                              136
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produced  are  latex-dipped  goods such as gloves.  Daily raw material
cons-umption levels are 28,000 jibs of compounded solid rubber  per  day
and 2,000 Ibs of latex per day

This  company  compounds  the, majority  of" its solid rubber stock in
Banbury internal mixers and roller  mills.   The  remaining  stock  is
purchased as a masterbatch and is mixed on mills.  In either case, the
material  is  fed  to  the  Banbury  or  mill  and  mixed with various
compounding agents.  After a prescribed mixing time, the materials are
sheeted off and air cooled.   JThe  sheeted  compounded  stock  can  be
pelletized or formed into extruded sheets depending on the type of end
product.                      |

To  form  pelletized  stock,  .the  sheeted  material is fed to a long-
barreled  extruder.   The  material  is  extruded  into  a  continuous
cylinder,  cooled  in  a cooling tank, and cut to a prescribed length.
The pellets, referred to as slugs, are fed to a  shaker  screen  where
they  are  air  coded and dusted with dry talc.  The cooled slugs are
stored until needed.

•To form extruded sheet stock, j the  rubber  is  fed  to  an  extruder-
calender.   The  extruded sheets are passed over cooling drums, dusted
with talc, cut to length, and ifinally sent to storage.

All rubber molded items at this plant  are  compression  molded.   The
presses are loaded with slugs jor sheets depending on the product.  Two
hydraulic  systems  provide pressure for the compression presses.  The
first is a deadweight water system.  The  second  is  an  oil  system.
Heat  necessary  for  curing  jis  provided  by steam circulated in the
cavities of the molding presses.  After molding, an  operator  empties
the presses, dips the cured mo'lded items in a cooling tank, and stacks
the  item on temporary holding skids.  The cooling tank water contains
a lubricant.  The molded items proceed to a die cutter which trims the
flash.  In some cases, an operator applies a silicone lubricant to aid
in the cutting.  Finished products, which are formed from  two  molded
pieces,  proceed  to  a seconcji steam-heated press where the pieces are
joined together with a rubber cement.

Latex used in the manufacture iof dipped goods is brought  in  by  tank
cars  as, a  50  percent  emulsion.   The  stock is blended with other
ingredients in a blend tank before being transferred to  a  dip  tank.
                            .. i
In  the  formation  of  a  final  product, molds are first dipped in a
coagulant.  The coagulant is a solution of calcium  nitrate  dissolved
in  alcohol.  The molds are next dipped in the latex dip tank and then
into a leach tank.  Finally the latex covered molds are cured in a hot
air oven.  The leach tank contains l«tO°F  water  'which  is  heated  by
steam  injection.   The  hot  jair  used  in  the curing oven is heated
indirectly with steam.  Once cured, the dipped goods are stripped from
molds which are recycled to trie coagulant tank for  the  next  dipping
operation.


                              I      '•'•."'•        .  •-
                              I

                              )37
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I
         Pharmaceutical   items   produced  by  this  plant must be washed before
         final packaging and shipping.   Washing is carried out in a single  100-
         gallon washing  drum using seven selquential steps.  The drum  is  first
        ,rinsed  with water to  remove  cbntaminants retained from, a previous
         cycle.  Next the items are loaded and washed in a chlorinated caustic
         solution.   The  next two washes are with detergent.  These are followed
         by  a neutralization wash, a hot water rinse wash, and a boiling water
         final rinse. The items are removep from the drum, dried in a hot   air
         oven, packaged, and eventually shipped.

         Process waste  waters  from this plant arise primarily from the washing
         of molded   and   dipped  goods.   Tjhese  wastes  are  characterized  by
         surfactants, BOD, COD, suspended iand dissolved solids, and pH spikes.
         Other process waste waters arise from leakages and spills of  oil   and
         water  from  heavy machinery.   Washing of dipping molds also produce a
         discharge.   The molds  are cleaned every two to three weeks.  A  fourth
         process waste  water comprises overflows and cleaning liquids from the
         dip tanks  and other latex handling facilities.

         Waste waters are treated with  calcium  nitrate  and  "ferro-floc"  ibo
         coagulate   the   latex   solids, folilowed by clarification to settle the
         coagulated  solids.   The  clarified  effluent  is  discharged  to   a
         municipal   treatment  system  for! further  treatment.   The principal
         characteristics of the primary effluent are:  COD, 700 mg/1; BOD,   150
         mg/1;  suspended solids, 800 mg/l;| extractable organics, 130 mg/1; and
         surfactants, 7  mg/1.
This plant manufactures latex foanj products.  Production lines include
mattresses, pillows, comfort seating, and slab  foam.   During  normal
operating  periods the plant is run continuously; however, at the time
of this survey a shortage of raw  (materials  had  reduced  production.
Production  at  the plant during the sampling periods was estimated to
consume 200,000 pounds per day of jraw materials including the  filler.
Approximately  135,000  to  150,000 pounds were dry latex solids.  The
plant is locates in  a  minor  urb|an  area  with  limited  plant  area
available for either production plant expansion or comprehensive waste
water treatment facilities.       j

Production of the latex goods utilizes the Talalay process.  Following
production of latex at another facility, the latex emulsion is trucked
to  this  plant  and pumped into storage tanks.  The latex then passes
through a freezing-agglomeration step where the  pH  is  lowered  with
carbon  dioxide  gas.   This  causes minor coagulation of the latex to.
produce larger emulsion solids.   JThe  latex  is, concentrated  in  an
evaporator which pulls off water vapor using a steam jet equipped with
a barometric condenser to condense the evaporated water vapor.
                                       138
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 After  concentrating,   additional  ingredients  (stabilizers, fillers,
 s\xrfactaivts,  antioxidants,  accelerators)  are added in the  compounding
 step.   The  latex  mix is  th'en transferred to the steam-heated curing
-presses using a transfer hose1.   The  high  temperature  of  the  press
 causes specific latex  ingredients to decompose, liberating gases which
 produce the foam effect. In [addition, carbon dioxide is injected into
 the  mold  to  assist   the   curing process.  The final foam product is
 cooled, rinsed with water,  dried, and inspected before shipment.,

 River water,  with a slight  chlorine addition, is used in the plant for
 washings and  cooling.   It is the only source of  nonpotable  water  in
 the plant.                   •

 The  principal  process  wastb   waters  from  this  plant arise during
 process cleanup and product wjashing.  Periodic washdowns occur in  the
 latex  storage  and freezingj-agglomeration  areas  to  clean up latex
 spills and  leaks.   These wast|e  waters are  laden  with  latex  solids.
 The final foam products are w'ashed countercurrently to the flow of the
 wash  or rinse  water.   .Progress  has  beerr  made  in  reducing  the
 quantities  of wash water needed by using  a counterflow washing recycle
 system.   An  additional  source  of  waste  water  arises  during  the
 evaporation  step.   Barometric condensers are used to condense vacuum
 3et discharges and the  combined condensates  and  cooling  waters  are
 discharged  directly.          !

 Cooling water is  once-through! and is discharged directly to the river.
 Boiler  blowdown   is  also   discharged without prior treatment.   Waste
 water facilities  are employed;  primarily   for  the  removal  of  latex
 solids and  zinc ions.  High concentrations of latex solids are present
 in   the  storage   and   freezer-agglomeration  wash downs.   These waste
 waters are  collected in  a pit!and transferred batchwise to a treatment
 tank where  the pH is adjusted]  and  coagulation chemicals  (alum  and
 polyelectrolyte)  are added.  Latex solids float to the surface and are
 removed with  the  tank overflow.
                              i
 The  clarified underflow wa?te waters are discharged directly to the
 river.   The skimmed latex solids in  the   overflow  are  screened  and
 containerized  for  disposal.!   The screen filtrate is returned to the
 chemical treatment tank  for  continued treatment.

 Waste waters  from  the product   washings   are  treated  in  a  separate
 system.   The  wash  waters  are  collected  in a  pit  and  are then
 transferred to a rapid mix tank where lime is   added.    The  resulting
 zinc  hydroxide  precipitate  jis  removed in a  primary clarifier.   The
 settled  solids are dewatered in a  vacuum  filter   and  trucked   to  a
 landfill.   The waste water is:discharged  directly  to the river.

 Plans  have   already been made  to upgrade the existing waste treatment
 facilities.   The proposed plant  will  collect the  .effluent  from  the
 batch  latex  waste  water  treatment system   and  the   zinc removal
                              39
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                                 - I
clarifier in an equalization -tank.I  The pH of the waste waters will be
adjusted with carbon dioxide  to  iprecipitate  zinc  carbonates.   The
waste  water  will  then be filtered in a diatomaceous earth filter -to
remove fine suspended solids and carbonates.  The  waste  waters  will
then flow to a municipal treatment plant for additional BOD removal.

At  present,  with  the  describedj  zinc removal and latex coagulation
primary treatments, the effluent  quality,  including  the  barometric
condenser  discharge, is as followjs:  BOD, 400 mg/1; zinc, 4 mg/1; and
Suspended solids, 50 mg/1.

Summary of Control and Treatment Technology

General-Molded, Extruded, and Fabricated Rubber Subcategpries

In-Plant Control

In~plant control measures and practices require  proper  handling  and
isolating   general   spills  and j leaks  of  potential  contaminants:
soapstone and other anti-tack agenjts, latex  compounds,  solvents  and
rubber  cements,  metal  preparati3n  wastes,  and  wet  air-pollution
control equipment discharges.

General Spills and Leaks

Most molding, extruding, and rubbejr fabrication plants (such  as  hose
or footwear production facilities) • can generate waste water containing
machinery   oils   and  greases  as  well  as  suspended  solids.   If
uncontrolled, these waste  waters ] can  enter  floor  drains,  thereby
polluting  the  plant  effluent.  ] In  plants,  such as cement dipping
facilities where less heavy machinery is used, the  oil  contamination
problem is noticeably reduced.
The  exemplary  subcategories  E,
F,  and G plants visited shared the
following common methods to  reduce  the  type  of  oil  contamination
described  above:   blocking  of  existing  floor drains, removing oil
leaks promptly with dry absorbent granules, and in some cases  curbing
the  problem  area  to  contain oil or grease leaks.  In cases where a
floor drain is required in order to discharge  uncontaminated  cooling
water,  for  instance,  a  collar | is installed around the floor drain
opening to prevent floor drainage jfrom passing into the drain opening.

Plants which have water and oil lelakages occurring at the  same  piece
of equipment often use oily-water Isumps inside the oil retention .areas
to  collect  the  highly  contaminated  water  in order that it can be
adequately  containerized  or  tre'ated.   For  cases  with  relatively
voluminous  leakages,  these  collection sumps are equipped with pumps
which empty the sumps by pumping the oily water to a location where it
can be treated or held or disposal;.
                            140
-------
        storage areas *»here fuel, maintenance, and  process  oils  are
kept  are frequent causes of oil pollution in a plant's effluent..  The
situation is aggravated at thejse  facilities  by  high  run-off  rates
during  storms.   The  most  effective way to prevent contamination of
large quantities of storm  water  is  to  retain  the  offending  oil,
preventing  its  entering  thej otherwise clean storm water and, at the
same time, roofing the oil contaminated  regions  to  keep  the  clean
storm water from picking up thje oil.

In  one case observed, compressor oil was transferred from a 55-gallon
drum to a smaller container in! the close vicinity of  an  open  drain.
The  floor around the drum and the drain opening was contaminated with
oil.  Coincident with this observation, oil globules appeared  in  the
final  plant effluent.  In another plant, discarded drums used to ship
process oils were stored in the cpen.  The ground was coated with  oil
and  the  stagnant  water  in ia nearby drain had a heavy layer of oil.
This oil layer would eventually enter the  plant  effluent  discharge.
These two cases point out thai; good housekeeping, as well as installed
control   equipment,  is  vitall  to  the  prevention" of  waste  water
contamination by oil.         •

In the plants where good housekeeping  and  sound  control  facilities
were used the oil loadings in the plant effluent were satisfactory.

Lead-Sheathed Hose Production|

In the manufacture of hose viei lead-sheath processes, lead-laden waste
waters  result.  The sources of lead are the  lead press  and cured hose
cooling water, and the vulcanizer condensate.  In  order to   properly
treat for lead, these streams Ishould be segregated prior to treatment.

Soapstone and Anti-Tack  Dip Solutions
                              I    '      '     •
The  spillage  of soapstone and other anti-tack solutions is controlled
in  exemplary plants  in a manner  similar   to   the  containment  methods
used  for oils and grease.  Floor drains  have been blocked  or  collared
to  prevent  the slurries  from entering  plant  drains and  sewers.   Spills
and drippage are mopped  up orjare simply  allowed to  evaporate.

In  industries  such as  cement clipping,  few floor drains   are  required.
In   the  area  where  the  final!dipped product is coated  with soapstone,
the soapstone  slurry system  is  closed  and little spillage  occurs.    A
similar  approach  is   feasible  for  all  types  .of  industry in this
category.

Latex Compounds               ]
               ~               I        .                .           '  «• .
 Several types  of  fabricated product require the  use   of  latex  during
 the manufacture.   Latex spills  can  occur  at the  storage loading areas,
 facilities   where  bulk  latex  is   transferred  to  drums, and at the
                            14JI
-------
 processing areas.
 latex  down  with
                    water.
                    Where such skills occur, it  is common  to  wash
producing  a  latex-laden  waste water.
the
 In
                         •  c-— ——-T--—«VJ  v*  J.vi <_WA-j.avacji  »
 addition,  drums are frequently rinsed clean with  water.   These   latex
 W3K f  "?ters are then chemically coagulated and  clarified,  usually in
,a batchwise treatment system.   I                                 .

 A more effective way to ha'ndle ijatex is the use of plastic   liners   in
 latex drums,   when the dru;m is r.eused, the old liner is  discarded.   m
 this manner,  waste waters from drum cleaning are  not generated.   Latex
 spills around storage and ^ransfer facilities are coagulated with alum
 T^oJrS ,,oo5  ^apeJ fT-°* ^he i9round-  ln th« processing areas  where
 latex is used, floor drain^ have! been blocked.  This approach is  used
 by  a  footwear plant which, although it was not  visited, was surveyed
 on this specific subject. |                                         "

 Solvents and  Rubber Cements     !
                          •I      j ' .•*•••:•>,• -V.v  -.-••• .:••• «-- ;!,/ !  ,,. ...-,.  •'
 Many plants use rubber cements as adhesives.  in  addition, the  cement
 dipping industry handles large quantities of cements and solvents.  In
 most of the cases observedi thesfe organic liquids are mixed  and stored
 XIVha*e?S   W1jhout  ,floor [Drains.    This  is by  far the most positive
 method to  control solvent or cement spills and  leaks.   Incidentally,
 solyents  should  be kept out ofjplant drains for reasons of safety as
 eJ losivlnlssent  quality'   sincf  they  have  high  flammability   and

 Metal Preparation

 The  methods   used  to prepare  and  recycle  metal components for rubber
 bonding were_essentially dry.   Degreasing liquids were used in  closed
systems and discarded when
                            saturated with grease.
                                 I
It  is  believed   that  some plants use acid pickling to prepare metal
components.  The  pickling and metal rinse waste will  exhibit  low  pH
and   high   heavy   metal  concentrations.    It  is  understood  that
precipitation of  the  metals  and]  pH  adjustment  is, carried  out  to
effectively  treat such  Wastes!  before  combination with other plant
waste waters.  Alternatively, the  pickling  wastes  are  containerized
and   hauled   from,  the  plant.    Plants employing  extensive  metal
preparation should control [waste waters from such operations according
to metal finishing regulations.  |
                                 I  -':'     -   -:'  '-'    '. .  •    '  '  -  '
Air Pollution Control  Equipment
wet scrubbing devices are used iri the rubber  compounding  and  product
buffiner  areas.   Althouah  wet  jscrubbing  devices  are  used to trap
                            sand-blasting   fines,   dry   ait-pollution
buffing  areas.   Although
rubber-buffing  and  metal
      . -    3       •u'-».«**. ,	_ ._„._„—-*.a  ^.jj.tit.,   vtj-jr    cu-i — uvjj.4.utxwn
control devices are also applicable and are used in many plants within
the industry.  in some plants where waste water discharge requirements
are   stringent   and'  the
                            use  of
                              142
         bag  collector  .devices  is  also
-------
inappropriate, the waste waters from wet scrubbing devices are settled
and filtered before discharge^ or a municipal treatment system is used
to accept the waste waters.  Wet scrubbers exist  within  some  plants
that- greatly  add  to  the  process  waste  water usage and loadings.
Additional limitations which take  into  consideration  TSS  from  wet
scrubbers have been applied tJD BPCTCA and BATEA,  BPCTCA is based upon
current  practice, while BATEA is dependent upon recycle and treatment
of concentrated wet scrubber waste waters.

End-gf-Pipe Treatment
                             I     --  -  -       -  - -          •   - -
In general, only minor end-of^pipe treatment is used by the industries
covered by this industry segment.  This is due  largely  to  the  fact
that  process  waste water contamination is limited to essentially two
parameters:  oil and grease, knd suspended solids.   In addition,,  good
effluent  quality  can be achieved most economically by employing good
housekeeping practices with well-designed in-plant control measures.

Of the Subcategories E, .F, and G plants visited, only two had  primary
•treatment  systems  and  none;  used secondary treatment.  Furthermore,
only one of these plants used j the  local  municipal  sewage  trtsatment
system  to provide the equivalent of secondary treatment.  These facts
indicate  that  the  magnitude  of  waste  water  pollution   is   not
appreciable  or  the  problem!  can  be effectively controlled by sound
prevention and in-plant control measures.   	:	•.			^_

One plant uses gravity separation to  remove  oil  from' the  combined
plant  effluent.   This  combined  effluent includes utility and storm
waters as well as process waste water.  In-plant control measures  are
employed as the primary method of oil reduction and the oil separators
are  designed  as  a  backup j system.   In addition the plant's boiler
blowdown,  autoclave  condensate,  and  compressor  condensates   pass
through  a  holding  pond to separate solids and oils from theses waste
water types before discharge.)  The  holding  pond  also  allows  these
waste waters to cool before they are discharged.

The  other  plant  (manufacturing  footwear) which does employ primary
treatment  uses  appreciable jquantities  of  latex  adhesives.     The
handling  of  these  materials produces latex-laden waste waters which
are chemically coagulated andj  allowed  to  separate  in  a  batchwise
manner.  It is debatable whether this treatment method for latex waste
waters is the most appropriate or whether the latex waste water can be
eliminated completely in the use of different handling and dry cleanup
techniques.   This  plant  utilizes oil collection-separation sumps to
trap oil leaks produced at the mills and other heavy machinery.

The quality of the effluent from the one plant which discharges  to  a
municipal  treatment  system 'is satisfactory for the municipal system
without primary treatment or pretreatment.  This quality  of  effluent
-------
                                  1  '        '
can  be  achieved  when  correct  waste water control and housekeeping
procedures are followed.           I

Wet Digestion Reclaimed Rubber Subcateggry
                                   i - .          '-.-••..
In-Plant Control                   j

The wet digestion reclaiming process is declining  even  more  rapidly
than  the  reclaiming industry as a whole.  There are only about three
wet digester reclaiming  plants  remaining,  and  the  incentives  for
process  modifications,  particularly  those  modifications leading to
lower waste water flows and loadings, are few.  However,  the  control
measures  used  by  the  wet digestion industry include containment of
pollutants by the recycle and reuse of waste water streams.

General Spills and

Oil and grease spills and leaks occur around the  heavy  cracking  and
grinding  machinery used to prepare the scrap rubber for the digestion
process as well as the milling areas  for  the  final  reclaim  rubber
product.  In addition, rubber fine? are generated which can enter into
plant  drains.   outside  storage areas used to store fuel, machinery,
and-process oils produce oil-ladenjwaste waters if spillage and  storm
water are allowed to contact each other.
                                 1  !   -, •' .  . - -•:•' -. -'•• "• :  •,-...'..:. '•-'•<' -y
The  accepted  method  of  controlling these types of contamination is
similar to that employed by general molded, extruded,  and  fabricated
rubber  plants,  namely,  containment  of  the  leaks  and spills with
separate handling  and  disposal  procedures  and  at  the  same  time
reduction  in  the  volume  of  water.  For example, storm and cooling
waters that are uncontaminated arejnot allowed to come in contact with
the polluting spills and leaks.  Good  housekeeping  is  an  important
element in the control of the contamination of cooling water and storm
water.

Digestion Liquor and Cil Recycle

The dewatering liquor is the major waste water stream by wet digestion
reclaim  plants.   The  reclaim plant visited  (Plant IJ uses a recycle
system which returns the dewatering liquor and reclaimed process  oils
to  the digestion step.  This system  is illustrated in Figure 9 in the
section on Plant I.

The dewatering liquor is collectedj at the rubber dewatering screen and
sent to a storage tank  from where it  is returned to the digester.  The
liquor storage tank requires constknt agitation  to  suspend  solids,
particularly  rubber  particles,  jbhereby preventing a dense and tacky
buildup in the tank.
ii
-------
Vapor condensates and cooling waters from the blowdown tank and  dryer-
are  sent  to  a  decanting  t£nk  where  oils  and other organics are
decanted.                     :
                              !    ;  i           "
The decanted oils are sent to an oil storage tank where  the  residual
water  content  is  drawn  off! the bottom, and the top layer  (oils and
organics) is returned to the digester for  reuse.   The  bottom  water
layer is returned to the first; decanter.
                              i
The  bottom  water  layer  from  the  first  decanter is pumped to the
dewatering liquor storage tank1 where it mixes with the digester liquor
before being returned to the digestion process.  Part  of  the  bottom
water  layer  from the first decanter is slip-streamed to the sewer to
blow down accumulating compounds.  It is this stream that  is  finally
discharged  in  the  plant's  Affluent.  The flow and loadings of this
discharge are lower than the equivalent stream without the recycle and
reclaim system.  This comparispn is shown in Table 15.

The oils and dewatering liquor, that are returned to the digestion step
of the reclaim process require makeup but the chemical usage  is  less
than the equivalent process consumption without recycle and reclaim.

Vapor Condensates             |                            -

In  theory,  it  should be possible to use vacuum pumps to exhaust the
blowdown tank and dryers.  However, the advantages of  steam  ejesctors
over  vacuum  pumps  are their; reliability, trouble-free operation 'and
overall economy.  The use of vacuum pumps would reduce  the  condenser
cooling load and the final volume of. condensate.

The  above  modification has mbre merit if indirect cooling condensers
are used in place of barometric condensers.  The volume of  condensate
with  a vacuum pump and indirect condenser would be considerably lower
than with a steam ejector and barometric condenser.
                              i
Scrap Defibering              |

The method by which the scrap irubber is defibered has  a  considerable
effect  on  the  loading  of the digester dewatering liquor.  If scrap
containing fiber is fed to the! digester together  with  the  necessary
defibering  - chemicals,   the j  dewatering  liquor  will  contain  the
solubilized fiber residue.  In:  addition,  the  defibering  chemicals,
which  are  discharged  along :with the dewatering liquor, can contain
contaminants, possibly heavy metals.  Furthermore, chemical defibering
precludes the use of the  recycle  and  reclaim  system  as  described
above.                .        j
                              -1'"     •     :      " .'-•'  '• •    '  •    •   -.-'''
As  an alternative to chemical' defibering, defibering by mechanical or
physical techniques can be used.  In brief, the waste  water  benefits
of  this  method  are:   fiberffree  dewatering  liquor,  no  chemical
                               i145
-------
defibering  agents  in  the  liquqr,  and  reduced  dewatering  liquor
discharge due to liquor recycle,  iln cases where liquor recycle can be
utilized,  the  usage  of process 'oils and digestion chemicals is also
significantly reduced.            i

Alternative Reclaim Process   .

The conversion of a wet digestion jreclaiming plant to any of the three
dry reclaiming processes  (pan, mechanical, or dry digestion) , in order
to improve the  quality  of  the  'plant's  effluent  would  constitute
considerably  more  than  an in-pljant control measure.  However, it is
appropriate to note at this point jthat the three  dry  processes  give
significantly  lower  waste  waterj  flows  and  loadings  than the wet
digester process.  The  wet  digester  process  can  more  readily  be
converted  to the dry digester prqcess than to either the pan (heater)
or mechanical processes.          i

End-of-Pipe Treatment      .       ;

Plant I employs little end-of-pip^ treatment; and a decanter  for  oil
and  grease separation.  This is the only wet digester reclaim process
known to discharge direc'tly to a  'stream  or  river.   All  other  wet
digester  plants discharge to municipalities which are reportedly able
to treat this type of waste water iadequately.  In  view  of  the  fact
that little end-of-^pipe treatabili^ty data exist, and since the few wet
digester reclaim plants still operating will most probably continue to
use local municipal treatment systems indefinitely, it is difficult to
comment meaningfully on the merits of potential, but unproven, end-of-
pipe treatments.                  |

However,  it  can  be  stated  positively  that  the  most  common and
apparently most appropriate end-of-pipe treatment  for  wet  digestion
process waste water is afforded by publicly owned treatment works.
                •               .  i .    • .
Pan   /Heater)>   Mechanical,   and  pry  Digestion  Reclaimed  Rubber
Subcateaory    *                   !

Jn-Plant Control                  :

.In comparison to the wet digester Iprocess, the waste waters  from  the
dry  reclaim  process   (pan, mechanical, and dry digestion) have lower
flow and are less contaminated.  This is due primarily to the  absence
of the dewatering liquor.  The scope for in-plant waste water controls
is  thereby  reduced  and  is limited to the containment of spills and-
leaks, and the  effective  condensation  and  decanting  of  vaporized
process oils and organics.        i
                                  i
                               146;
-------
General Spi-Lls and Leaks           j

The  flows,  characteristics,  :and  applicable  control methods of the
spills and leaks in the dry reclaiming industry are similar  to  those
found in Subcategories E, F, and G.

The  spills  originate  at  heavy equipment, and material handling and
storage  areas.   The  contaminants  are  characterized  by  oil   and
suspended  solids  and  are  prevalent  in  the  scrap cracking, scrap
grinding, product milling, and' oil storage areas.

Successful control techniques  include good housekeeping,  curbing  and
drain  blockage  to  contain   Ithe  spills, and isolation modifications
which restrict the  spread  ofj the  polluting  material  and  prevent
contact with uncontarninated waters.

3LiE£E Condensates
                               | ' •            '            '    .
The  exhaust  vapors from the  devulcanizer ovens require condensing to
minimize air  pollution.   This  exhaustion-condensation  is  normally
carried   out   using  a  steam-ejector  barometric-condenser  system.
Although this type of system i£ reliable and economic, the  volume  of
condensate  and cooling water  is greater than the volume of condensate
produced by a vacuum pump and  noncontact condenser.

Plant I, which operated both wet digester and pan  reclaim  processes,
decanted the barometric condenser cooling waters plus condensates from
the  pan process, recycling both the reclaimed oil and water layers to
the wet digester process.  It  (is  believed  that  the  reclaimed  oil
cannot  be  recycled  to  the,  ; devulcanization step of the pan process
because the quality of the f-eed process oil is more  critical  in  the
pan  process.   Therefore,  for  plants with only the pan process, the
oily vapor condensate must be  disposed of as a  waste.   However,  the
basic  technologies  used  at  Plant I to recycle the components of the
vapor condensates can be applied at  plants  operating  only  the  pan
process  to  control  the  flow and loadings of vapor condensate waste
waters.   The  barometric-condenser  cooling  water  and  condensibles
mixture  can  be decanted.  The top cil layer can be containerized for
disposal and the bottom water  layer can be cooled in a noncontact heat
exchanger before it  is  recycled  to  the  barometric  condenser  for
cooling  water.   A portion of the water layer should be slip-streamed
to the plant sewer to blowdown!accumulating organics.

Ejid-of-Pi£e Treatment          |
          ~    ~    ~   "    '   I              '.   •                  '
The dry reclaiming plants throughout the industry do not generally use
end-of-pipe treatment for their waste waters.  A large  proportion  of
the  plants  in  existence  discharge  their waste waters to municipal
treatment plants.  No  treatability  data  exist  for  the  biological
treatment  of pan, mechanical,jor dry digester processes.  In fact the
BOD is so  low  (20  mg/1  typically)   that  biological  treatment  is
inappropriate.                  :
                              147
-------
 It  is  possible  -that  separators   or  holding ponds  are used by some
 plants to act as a catch-all for iall plant waste waters  in  order  to
 trap  oils  and  suspended solids that have bypassed or  escaped  in  in-
 plant controls previously described.  It is belived that such a  catch-
 all  is  not  necessary  if  adequate  in-plant   control    and   good
 housekeeping are practiced.        -

 Latex-Based Products Subcateqories

 In-giant gontrol
 Since Subcategories J and K represents the latex-based industries,  the
 in-plant  controls employed by this industry are designed primarily to
 control, handle,  and treat Iatex4laden  waste  waters.   In  addition,
 some  individual  streams such as jfoam rinse water or dip form-cleaning
 water require special control and treatment measures.

 general Latex Spills and Leaks  ]
                                 j    ' . , - -    . '           .„,.:,.
 Both the  latex-dipped  goods" (Subcategory  J)  and  the  latex  foam
 ^Sufocategory  K)   industries  generate  latex-laden waste waters.   The
 quantity of  latex  consumed  by i  the  latex  foam  plant  visited  is
 considerably  higher  than the latex usage at the average latex-dipped
 goods .production  facility; generally, the latex shipping, storage, and
 .handling procedures are different."

 In a dipped goods facility the latex is generally shipped in  by  tank
 car   or  tank  truck  and  transferred  to  a  storage  tank.   After
 compounding, the  latex mixture is usually taken into the dipping areas
 in 55-gallon drums.  The major spillages and vsshdowns  occur  at   the
 storage  unloading  area  and  in  the latex compounding building.  In
 addition, the transfer drums require cleaning between latex mixes   and
 this  produces  a latex-laden waste water.  In the dipped goods plants
 that were visited, no treatment of the latex waste waters  is  carried
 out before they mix with the total plant effluent..
                :                 I
 In the latex foam plant, the latex-laden waste waters are generated at
 the latex concentration, intermediate storage, and curing press areas.
 The  waste  waters  from  these operations are collected in a separate
 drain system and treated by chemical  coagulation  and  clarification.
 As  part  of this overall system^ the areas where the latex spills and
 leakages occur  are  designed  t6  restrict_.the  spread  and  further
• contamination  by the latex wastes.  The coagulation and clarification
 system for latex waste water consists of a collection pit which  feeds
 a  batch  treatment  tank   (10,000  gallons).   The  waste water pH is
 adjusted using sulfuric acid and]  caustic  soda  and  the  solids   are
 coagulated  using  alum.   The  foagulated  solids  float to the water
 surface-where they are skimmed off and screened in  a  strainer.   The
 screened  water  is  returned to; the treatment tank and the solids are
                                146
-------
 landf illed.   The clarified waste water overflow is discharged  to  the
 plant drain.                  ;                           -

 Foam Rinse Waters
            After curing, latex. foam requires rinsing to remove excess compoundina
            and  curing  agents entrained in the foam matrix.   The resulting rinse
                   *1   U   Sie  Z±nC <>m°unds
             U? S2^ie Z±nC <*>mP°unds a«d the  zinc  concentration   n
             o?J?I  .^ically 700 mg/1) .  A significant reduction In
 the  volume  of this rinse water was achieved at Plant L by employina a
       r"nini   Process-  Thi* is represented schiSSJg  i£
                       11Z'  The. zinc-laden rinse water is then treateS
            for  zi       n                 .                              n  reae
            for  zinc  removal  in  a  continuous    chemical   precipitation   and
            clarification  system.  Precipitation is accomplished byPadjus?"ng ?Se
            PH to approximately 12 by thej addition of lime,  and by the addition of
            a polyelectrolyte.  The operation is carried  out in a rapid mix   tank
                                                        a
The mixture then passes  to  a  flocculation tank where thpre
SSfficiSS   J? procffses  ar^  completed.  The tank has mild a.t
sufficient   to   gently mix,  the  waste  water  components  but  not
sufficiently powerful to break  or  destroy  the  desired  floe.    The
flocculation   water   then  enters   the  clarifier  where  the   zinc

          emJ/lfetf ^ ThVla£if ied  e"l»ent  ^inc^concentxaKSn
           ^  } •  -S ,^en  dfscharged to combine with the  total  plant
    l      ?5 zinc sludge  is  drawn  off  from  the  bottom  of  Se
   *hf  •  f  v fil^red on a:vacuum filter.   The filtrate  is recycled
   the mix tank.  The  filtered sludge   is  sent  to  landfill/    The
                            ^Pre«eats the zinc-lime  sludge to  enhance
                  °f ^he ?lud?e-  Studies are to be   made  to   reclaim
           an$ ^^Cycle  "  t»  <**  l^ex  compounding  stage.   The
            of this approach has yet to be determined.
Form Cleaning Wastes
                   -
'f                    •                    !•-.;••
J          S o°St latex dipping facilities, the dip forms require cleaning.   In
MS          3Omf>  r?A»so  +-VIT 
-------
  type of stubborn rubber deposit is
  rinse  the  acid  from  the  JLi
  chromic acid and if SaracteriSe
  A  satisfactory  method  of
  employed by the industrv  i«      K   v,

  S. S -*& rSs%   If
  hexavalent  chromium  reduced
                                                          t0 °lean this
                                                      chro"»ic acid  and
                                               Jin?* Watex «*l*cts the
                                             *?  hexavalent  chromium.
                                            - type  of  waste water, as


                                                      ^   ^d  and  the
    then dried on a  lude

             Treatment
                                  bed?
                                                                 sludge
 effluent is then discharged  to
 effluent  guality is suilable
                                                            .
                                                      ?lariflea  Primary
 a receiving strJa
                                                   °f
                                              •
                                           prior to final discharge to
Some latex  dipping  plants
treatment  systems  to  treat the '
well.  Few plants use activated
that  the  waste  water  16adin<
produce an adequate biomass.   Th
pond systems are more applicable
                                                                -  pond
                                                  Tnese systems perform
                                                     Jt  is  considered
                                                   BOD,   are too low to
                                                  lagoon  and  settling
clarlf ication  o   the
suitable and is possibly
Plants that are KjJcen?
                               solis
                                                   .               and
                                             type °f ^eatment is very
                                                             for  mos?
                           the
municipal  system.   Boh
waters after zinc removal
gallon equali2ation tank.
carbon  dioxide to lower the
PH will be higher than 8 because
              and
                                          i       dlschargi"9  it  to  a
                                          J 5* WaS ** a"d r±nSe  Waste
                                          lSw  SJff ed^hrfu5h  « 25,000
                                              ""I  be  treated  with
                                               .8 Un±tS  (the  «lginal
                                                of6 Water' after 2inc
                                                           H
       before it
                             150
-------
effluent removing  the  fine  carbonate  precipitate.   The  car-foonate
precipitate  will include a portion of the residual  zinc that has been
carbonated.  It is anticipated the filtered effluent will  eventually
be  discharged  to  the  local; municipal system.  This will not occur
until the city plant is expanded/ in a few years' time.
                               151
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                                         SECTION VIII               .
                                        -•  !           "•••'-..•         '
                          COST, ENERGY, ANJD NONWATER QUALITY ASPECTS
                                          I                                        :

            General Molded. Extrudedr and fabricated Rubber Subcateoories

            Two  fundamental  approaches  can  be  applied  for  the  control  and
            treatment  of process waste waters produced by Subcategories E, F, and
            G production facilities.      ;

            The first approach is to combihe process and nonprocess  waste  waters
            and ' to treat the entire plant; effluent,  where land is available, on-
            site end-of-pipe treatment is practiced at some  of  the  plants,.   At
            other  plants, the total effluent is discharged to the local municipal
            treatment facilities.  In eithfer case, the  reasons  for  treating  or
            discharging a combined effluent are as follows:

                1.   In general molded, ex-truded, and  fabricated  rubber  plants,
                     in-plant  sewers  forj process and nonprocess waste waters are
                     usually  combined,  thus  making  combined   treatment   more
                     attractive.          !
                                          I -  •- • -   •• ,    	   .   - -        •_   :
                2.   Process flows are usually small relative to nonprocess flows.

                3.   The treatment of nonprocess  waste  waters  has  received  the
                     bulk  of  industry's jattention.  For example, high suspended
                     solid loadings contained  in  blowdown  and  water  treaitment
                     wastes  are  a major pollutant in the combined plant effluent
                     from rubber process ding facilities.

            However,    end-of-pipe   treatment   systems   also    have    several
            disadvantages:                j
te*                            -            "   "              •        "
 "             -.I-   The combined effluent treatment system usually  requires  oil
                     removal  equipment  and/or a holding pond or lagoon system to
                     separate the oil.   Lagooning of the wastes generally requires
                     considerable land area.
                                          I   •        -•,---     .   -  i  - -    - -  .    •
                2.   Because of dilution, the effectiveness of treatment  for  oil
                     and  solids  removal from process waste water is reduced.   In
                     several of the  systems   observed,  oil  passed through  the
                     system with low removal  efficiency,  because its concentration
                     was  below the capabilities  of the treatment system employed.
                     This  phenomenon!  occtkrs  even  though  the  oil  loading  is
                     significant,   because; of the dilution afforded by nonprocess
                     waste waters.         ,                      .
                                          i'53
-------
                                  !                 •  '  :
 The second approach employed is control and treatment of  an  isolated
 ^VL^  KUt^d process w*ste watei^-  This approach has been followed in
                 ~,,~u,-.-,-,..  Qr wholly-segregated process and nonprocess
                                  i
,
            *          a?Proach  is  the  reduction,   containment,  and
           of the contaminated process waste waters prior to treatment
 The  principal advantages for this treatment approach over the end-ofl
 pipe treatment of the combined plant effluent are:

     1.    Higher pollutant {primarily oil and suspended solids)  removal
          rates.                  :

     2.    Smaller treatment units jand land area requirements.

 The primary disadvantage of  a  segregated  system"  approach  is  that
 separate  process  and  nonprocess  sewers  are  required.    This will
 necessitate in-plant modifications which, if  not carefully  planned,
 can lead to significant production disruptions.

 Evaluation  of these alternatives! indicated that  control  and treatment
 of  segregated process waste waters is the most effective  and generally
 applicable  treatment  approach  for   this   industry.     End-of-pipe
 treatment  of  combined  waste  Waters  is  not feasible  for pollutiS
 control  because of  the ineffectiveness of such systems  in  removal  of
                    Waste  water   ontaminants, and   the  larger  land
Incidentally, a viable alternative  treatment for waste waters  (process
as well as nonprocess) generated  by this  industry is discharge  to   1-he

adequa?f pretL?Sint?reatment "I*''  ^ ^^e is contingent on
                                  i
All costs presented are related to the control, followed by treatment,
?£  segregated  process waste water  streams.  It can be further stated
that this type of treatment approach is  considered  to  be  the  best
practicable  control  and  treatment technology currently available to
tiri€ IHQUS try •

With proper in-plant control, the j process streams consist  of  readily
vJ?»™Si?  l^ricating  and  extender  oils,  and  settleable  solids?
Volumetric flow rates for process! waste waters are small.   Therefore,
AP? *™ !£   treatment applicable from a proven operation basis is an
API-type gravity separator.   The  performance  and  efficiency  of  a
                        ? iinProve^ fcy addition of an filter coalesces
                        intercePtor  (CPI)   type  of  device  is  also
            generally to this industry.  The choice between the API or
  tero? Wli1 ^?pend °n land availability and the type of  waste
water  control,  handling,  and treatment equipment already present at
the plant.   Since the cost and treatment effectiveness of the API  and
                                  !
                               154 i
-------
CPI type separators are  comparable,  the effluent limitations treatment
and costs presented are  based on the use of API type separators.

Effluent  quality  data  for  Efubcategories E, F, and G are presented in
Tables 20, 21, and 22.   The   treatment  basis  includes -isolation  of
wastes  with curbing, protection of  uncontaminated waste streams (such
as cooling  water  and   storm  run-off),  blocking  unnecessary  floor
drains, the covering of  oil-handling areas to prevent contamination of
storm  run-off,  and separation of settleable solids and oily material
from the waste water.         j
                              j-   *--   •' •	'  .• ••           •    	
A more detailed description  of the recommended facilities is presented
in the Subcategories E,  F, arid G portion of Section  IX,  and  a  flow
diagram of a typical system,  |used as a basis for costing, is presented
in Figure 10.                 !
Treatment Cost Data
                             I
Data  collected  during  the 'plant operations and waste water analysis
visits plus data from Corps  'of   Engineers  permit  applications  were
utilized  to  'obtain  typical  plant size and process waste water flows
and raw loadings.  The analysis  approach and findings are described in
Section V.                   |            ,

As stated previously, Subcategories E,  F,  and G plant effluents can be
divided into two groups:   process and nonprocess  waste  waters.   The
process  waste  waters  consist  of mill and curing areas, oily waters,
anti-tack and latex  spills  ;and  leaks,  area  washdown  waters,  wet
scrubber  discharges,  and contaminated storm waters from material and
fuel oil storage and handling  areas.    The  nonprocess  waste  waters,
which  are  not  the  subject  of  this  document,  include  sanitary,
noncontaminated storm water, and utility waste waters,  such  as" once
through noncontact cooling water, boiler blowdown, cooling tower blow-
down,   and  water  treatment'  wastes.    In  addition  noncontaminated
process-associated waste waters   such  as  extrusion  contact  cooling
waters,  and  hydraulic   (hose  manufacture)   and conductivity (cement
dipped electrical gloves)  test waters can be included with  nonprocess
waste  waters,  for  the scopje of this  document, since they should not
require any treatment at all prior to discharge.   These  waters  need
not  be  mixed  with  other  process  waters  prior  to treatment, and
therefore should not affect the  treatability of the waste waters.
                             j                         •                ; •
The aforementioned data sources   indicated  that  the  following  flow
adequately   described   the ;  process   -waste   waters  generated  by
Subcategories E, F, and G  plants:
    Typical Plant Size
    Product Size  Range
kg/day (lb/day) raw materials  kg/day  (Itj/day) raw materials
    Small:     900  (2,000)
   Medium:   7,700  (17,000)
    Large:  15.40C  (34,000)
less than 3,720 (8,200)
3,720:10,430 (8,200-23,000)
greater than 10,430 (23,000)
 Process W^ste
  Water Flow
  L/day (gpd)

14,700 (3,900)
75,800 (20,000)
95,900 (25,300)
                               155
-------
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          From  these  typical  flow  values  for  Subcategories   E,   F,   and  G
          facilities,  treatment  cost  data were generated and are presented in
          Tables 20, 21,  22,  and 23, as  well  as  the  estimated  raw oil  and
          suspended . solids   loadings  of the process wastes associated with the
          three  typical   plant  sizes.   The  cited  costs  for   all  sizes  of
          Subcategories E, F, and G production facilities are  based on the cases
          where no treatment  facilities that could be modified yet exist,  and no
          reduction  or   isolation  measures for the containment  of contaminated
          process waste waters have been taken.  These cases were  chosen   since
          the  design  considerations  (i.e., the influent raw waste  loads) were
          selected  to represent  the  expected  raw  waste   load within  each
          subcategory.  This  results in thfe generation of cost data which  should
          be  conservative when applied tb most of the plants in this industry.
          Relatively conservative cost figures are preferred for   this type  of
          general economic analysis,      j             ~         •                       gp
                                           | •'••"•"                :                    fe
          The  total annual  costs for the BPCTCA and BATEA control and treatment       m
          technologies can be expressed as; incremental costs .per   unit of  pro-
          duction  or   raw material consumption.  Study of the cost data  for the       j
          three  typical   plant  sizes  indicates  that  the   BPCTCA   and  BATEA  .     t
          treatment    costs    per   unit  j of   raw   material consumption  are
          approximately:                   ;

              Typical Plant Size       Annual ^Treatment Cost   Incremental Treatment Cost
          kg/day Xlb/day)  raw  material . August 1373 jdoliars   cents/kg U/lb)  raw  material

1    '          Small:   900  (2,000)        38,700!               14.3 (6.5)
!,    ;         Medium:  7,700(17,000)        75,300                3'M1'!(
I              Large: 15,400 (34,000)        95,900                2.1 (0.9)
                                           i
i
|           The above incremental costs are jbased on a  300 working-day year;  that
i           is, 50 working weeks per year and six  (6) operating days each week.
.                    .    ^               .     .        _          .
           It  can be seen that the incremental treatment costs to the small- and
           medium-sized plants are extremely   high.   compared  to  the  cost  of
           rubber  raw  material   (approximately   30  to 50 cents per pound), the
           treatment costs  appear  to  be ; a  burden   on  the . small  plants  in
           particular.   This analysis underlines  clearly the cost benefits to be
           derived by complete  elimination  of  process  waste  waters  by  good
           housekeeping  and  closed  spill; and leak containment facilities or by
           utilization of the local municipal  treatment system.  In addition, the
           elimination of direct discharge ,of  process  waters to navigable  waters
           will  eliminate  the  expense  c|f   waste water  analyses  and  permit
           reporting.                      j
                                           i --.r-
-------
      The capital costs were generated on a unit  process  basis,  with the
      following  "percent  add on" figures!applied to the  total  unit process
      costs  in  order  to  develop  the  total   installed    capital   cost
      requirements:                        i      .
                      Item                !

      Electrical                          i
      Piping                              [
      Instrumentation                     I
      Site Work                           I
      Engineering Design and Construction •
        Supervision Fees               .   j
      Construction Contingency            j
                                        Percent of Unit process Capital Costs
                                      Small Plants    Medium and Large Plants
                                          15
                                          20
                                          15
                                          10

                                          10
                                          15
12
15
 8
 5

10
15
i
III
Some  of  the  "percent  add  on"  costs are higher in the case of the
small, Subcategories E, F, and G plapts than the equivalent values for
the medium and large plants since these costs  are  disproportionately
higher (in terms of a percentage of the unit process cost)  in the case
of small plants.                    i

Since  land  costs  vary  appreciably  between plant locations, it was
decided to exclude land cost from the total  capital  cost  estimates.
Land costs must be added on an individual case basis.

Annual costs were computed using the following cost basis:

                                     Cost Allocation
                                    i                    -
                               10 percent of investment
                                    i
                               "5-year straight line with zero
                               salvage value
                                    j
                               Includes labor and supervision,
                               chemicals, sludge hauling and dis-
                               posals, insurance and taxes
                               (computed at 1.6 percent of the
                               total capital costs), and main-
                               tenance  (3.2 percent of the total
                               capital cost)

                               Based on $0.015 kw-hr for electri-
                               cal power
      Capitalization

      Depreciation


      Operations and Maintenance
      Power
      The  short-term  capitalization  and  depreciation write-r-of f period is
      what is currently acceptable under c|urrent  Internal  Revenue  Service
      Regulations  pertaining  ^to  pollution  control  equipment.   Economic
                                       162 i
-------
 analysis  indicates other allowable methods of  depreciation  write-off
 are   more  advantageous.   The annual costs presented in this document
 have  therefore been overstated.  The document.   Economic  Analysis  of
 Effluent    Guidelines  The  Rubber  Processing   Industry   (Phase  II) ,
 contains  revxsed annual costs,  reflecting optimum depreciation  write-
 off.                            :  .  .      .    ..       •'

 All   costs,   capital  and  operating, were computed in terms of August
 11973  dollars,  which correspond to an  Engineering News  Record  Index
 ([ENRJ value of 1920.           i    .
                                i  -    "  :  .       '     •.   , "
 Energy Requirements        -    j

 Energy  input  is related solely -to the need for electric pumps to pump
 process waste  waters  from  the j plant  areas   through  the  treatment
 system.   The   additional power requirements for control and treatment
 systems are small and deemed minor in comparison with the power usages
 of rubber processing machinery .and equipment common* to  the  industry.
 The   power  requirements  for  waste  water control and treatment are
 estimated to be;                !
                                i  ...    ,   •      .. .   • .

 ~ —   Typical Plant ..Size - __  Treatment Equipment Power Requirements
 kg/day (Ib/day)  raw material   j                 horsepower  - --

   Small:      900  <2,000)      •                     6
  Medium:   7,700 (17,000)      !                     8
   Large:   15,400 (34,000)      |                    12

 Electrical costs,  as presented in Tables 20, 21,  and 22, are estimated
 at $0.015 per  kilowatt hour  which is equivalent  to $98 per horsepower-
Nonwater Quality Aspects        i
             —    w_ -        i

The primary nonwater quality aspect deriving from use of  a  separator
is  the  need  for disposal of oil and solids.  Additional solid waste
results from the use of a nonregenerative type filter coalescer.

Disposal of process solid waste, such  as  waste  rubber  or  rejected
products,   is   a  problem  confronting  the  industry  as  a  whole.
Additional solid waste results from the drumming of waste liquid, such
as latex solutions, for off-site i disposal.  Many manufacturing plants,
particularly in the northern  states,  are  finding  it  difficult  to
locate  and  arrange  for  service  at  satisfactory  landfill  sites.
Fortunately, the additional solid  waste  generated  by  the  proposed
treatment  technology is very small relative to the normal solid waste
generated by the production facility 'and is considered insignificant.
                                |         •   .••-..•
Land requirements for the treatment system  are  small;  nevertheless,
certain  facilities  located in highly congested urban areas will find
                               163
-------
                                 I          ...
it difficult  to  allocate  space  for  even  this  minimal  treatment
facility.   These  plants  may  t»e  forced  to turn to other treatment
methods or to approach zero discharge to navigable waters by  advanced
housekeeping and control techniques.                 •
                            •  •   I' -   •   •            -•••"'-
For  those  waste  materials considered to be non-hazardous where land
disposal is the choice  for  disposal,  practices  similar  to  proper
sanitary  landfill  technology  flay  be  followed.  The principles set
forth in the EPA«s Land Disposal ,6f Solid Wastes Guidelines  (CFR Title
40, chapter 1; Part 211) may be used as guidance for  acceptable  land
disposal techniques.             ]
                                 i
For  those  waste  materials considered to be hazardous, disposal will
require special precautions.  In 'order to ensure long-term  protection
of   public  health  and  the  environment,  special  preparation  and
pretreatment may be required prior to disposal,  if land  disposal  is
to  be  practiced,  these  sites .must not allow movement of pollutants
such as fluoride and radium-226 t!o either  ground  or  surface  water.
Sites  should  be  selected  that:  have  natural  soil  and geological
conditions to prevent such contamination or, if such conditions do not
exist, artificial means (e.g., liners)  must  be  provided  to  ensure
long-term  protection  of  the  environment  from hazardous materials.
Where.appropriate, the-location of solid hazardous materials  disposal
sites  should be permanently recorded in the appropriate office of the
legal jurisdiction in which the site is located.

Lead-Sheathed Hoge Plants        ;

For plants producing hose via lead-sheath processes, control  of  lead
is  required.  Treatment for lead should begin with the segregation of
lead cooling waters and vulcanizer condensate.  Treatment for lead can
be accomplished by pre-coat filtration which industry has stated would
cost $90,000 for a 28,750 Ib/day £lant.   Other  control  technologies
appear  to  be  also reasonable.  Recycle of lead-laden waters using a
cooling tower, and treatment of a' concentrated blowdown stream may  be
more  advantageous.   This  would  reduce  water costs and result in a
smaller more concentrated stream jto treat.

Wet Digestion Reclaimed Rubber Sufacateaorv

The rubber reclaiming industry is; presently undergoing  a  decline  in
both  the  number  of  operating ! plants and the quantity of reclaimed
rubber produced.  The wet digester reclaiming process  has  borne  the
brunt  of  this  decline,   and  it  must be assumed that the financial
resources of wet digester reclaim1 plants and their ability to shoulder
further operating costs  such  as:  waste  water  treatment  costs  are
limited.    in  view of this and since all of the existing wet digester
plants discharge their waste waters directly or are connected  to  the
local  publicly  owned  sewage  treatment works, it is not possible to
propose an end-of-pipe treatment technology which has been  proven  to
                                164
-------
be  operable  and successful While in service, as well as economically
Kracticable.             ."!'..
                              I ...   . -   ,       .        - ;      .      „
With  this  in  mind,  attention  has  been  duly  given  to  in-plant
modifications to the wet digestion process which have been implemented
and  proven  successful  in  at  least one plant.  Such modifications,
while reducing waste water pollution and end-of-pipe treatment  needs,
also   have   the   potential] to  reduce  raw  material  wastage  and
consumption.  However, based  !on  the  preliminary  findings  of  this
guideline  study,  it  cannot  be  said  that the yearly reductions in
process operating costs afforded by the  in-plant  modifications  will
offset   the   annual   operating   and   maintenance  costs  directly
attributable to the modifications.  Such benefits can be assessed only
by personnel intimately familiar with the wet  digestion  process  and
the economics of is operation.

The  principal waste water streams in a wet digestion relaim plant are
the dewatering liquor and -the vapor condensates from the blowdown tank
and dryer.  The type of treatment proposed for Subcategories E, F,  G,
and  I,  namely, the isolationi of wastes loaded with oil and suspended
solids followed by oil and  solids  removal,  is  not  appropriate  as
BPCTCA  control  and  treatment  for  Subcategory  H  since  the costs
benefits are not favorable.  This argument is particularly valid  when
the  minimal  benefits  to be achieved by this type of alterations are
compared to the greater pollution reduction that can  be  attained  by
the  application  of the recommended recycle.  It should be remembered
at this point  that  the  wet : digester  process  .is  only  marginally
profitable  and,  at -present,; cannot bear large waste water treatment
costs.  In addition, most wet .digester plants discharge  to  municipal
systems and will be subject to pretreatment guidelines.

A  fundamental change that can be made to the wet digestion reclaiming
process is the conversion fron\ chemical defibering to  mechanical  de-
fibering.  With chemical defibering, defibering,chemicals are added to
the  digestion  mix.  The fibe;rs are solubilized in the digestion step
and leave the process system in the dewatering liquor  which  is  dis-
charged.   The  defibering  chemicals, which can be of a toxic nature,
are an additional  constituent  of  the  dewatering  liquor.    In  the
mechanical -defibering  variation,  the  scrap rubber is finely ground
prior to digestion.  The freed!  fiber  is  then  elutriated  from  the
rubber scrap on air separation tables.
                              I  ;        '  -             •
With  mechanical  def ibering  the  dewatering  liquor  is free of high
levels of solubilized fiber as well as the chemical defibering  agents
themselves.    costs   incurred .by  a  conversion  from  chemical  to
mechanical defibering have not been fully developed for  this   document
since  the  required  technology for the conversion is specific to the
reclaiming industry and outside the scope and technology boundaries of
the guideline study.  However,; the  costs  associated with  a  recent
conversion  from  chemical  defibering  to mechanical fiber separation
                             165
-------
  chemical,
                                                  digestion
                                                              plant from
                                                of  the  process  waste
                           In  eSIence  ?^ ^   ^re°rle 8ystem to tte
                         ^
 wet digestion  process.   In  eSIence
 recycled  back  to  the digestif
 contaminants and a make-up of the  io        .
 the vapor conden sates Irom ?he                q°'
 recover  the  insoluble  oils
 recycled to the digestion
                                                          8ystem to
                                                                can  be
                                                        of accumulating
                                                      At the 8ame  ^
                                                        are decanted to
                                                       &nd    "K* «r« .
 for  this  system to
 be fiber-free  in  order
                                                              in  order
 treatment  costs.
schematic flow diagram of
a basis for capita! and

treatment Cost Data
                                                            f°ntro1 an<3

                                                    riaim
                                                    in
                                                                 X.  A
                                                                and is
kilograms  (110,000  poun
generated by  the  deSaterina
estimated  to  be  app?oSmatelv
from plant visit data          Y
                                                    .
                                                    ±S rated at 54'000
                                       , *   • Pfocess waste water flow
                                      nnS \ .^ondenser  discharges  was
                                     <00(> liters per day (104,000 gpd)

applied to nOEt of the p!an
                              166
-------
Investment
                                                     Control Technology

                                                         §126,000
                                                                       1
Annual Costs

     Capital Costs

    • Depreciation

     Operating and Maintenance Costs
      (excluding energy and power costs)

     Energy and Power Costs

Total Annual Costs
                          12,600

                          25,200

                          19,300


                           fr.700"

                        $ 61,800
 Parameters
 kg/kkg(1b/1000  Ib)
 of product

      COD

      SS

      Oil
Raw Waste
  Loads  !


   9.75  '
         i
' 256.10  i
         I

  27.29  !
Effluent Quality



     6.11

     2.31

     0.58
 1The control  technology  includes  recycle |of dewatering liquor and  decan-
  tation of vapor condensates  followed  by recycle of the oils  and water
  underflow.                              ,...._...
 Table 24 - Estimated Waste Water Control  Costs for a Wet Digestion
            Reclaim Plant (Subcategory H)  i

                                          I     •  •       :.-'••
                                167
-------
                                   i            Percent of Unit
                    -•--ff      .     ;          Process Capital Cost
                                   !        -      -     ,.•','•
          Electrical               I                  IR
          Piping                   |                  ™
          Instrumentation          i                  ,c
          Site Work                |                  JJ
          Engineering Design and   j
            Supervision Construction                 V0"
          Construction Contingency i                  15













                                                     .

Annual costs were computed using th|e  following cost basis:

          —~                     j   ....      Cost  Allocation

Capitalization                  10 percent of investment

Depreciation                    5.^ straight line WJLth zerQ
                                salvage value.

Operations and Maintenance     Includes labor  and  supervision, '
                               chemicals, sludge hauling and dis
                               posajls, insurance and taxes
                                (computed at 1.6 percent of the
                               totaiL capital costs) , and main-
                               tenance (3.2 percent of the total
                               capital cost)
                              168   i
                                   i
-------
 Power
                                Based on $0.015/kw-hr
-The  short-term  capitalization  and  depreciation write-off period is
 what is currently acceptable tinder current  Internal  Revenue  Service
 Regulations  pertaining  to  industrial  pollution  control equipment.
 Economic analysis indicates other allowable  methods  of  depreciation
 write-off  are  more advantageous.   The annual costs presented in this
 document have  therefore  been  overstated.   The  document.  Economic
 Analysis  of Effluent Guidelines The Rubber Processing Industry (Phase
 II), contains revised annual costs,  reflecting  optimum  depreciation
      *"
 All  costs  were   computed  in  terms  of  August  1973  dollars which
 correspond to an  Engineering News Record Index (ENR)  value of 1920.

 Energy Requirements          i

 The waste  water control  and recycle  system requires electrical  enerov
 for  the   operation  of   pumps  and   mixers.   The  power needs  of the
 equipment  are modest and approximate HB horsepower.
 Honwater Quality. Aspects "    \
 There are  few nonwater quality aspects to be considered with this con-
 ™2ia ^eC?n0i0FC:   -In  order  t°  employ  the  proposed   technology,
 mechanical  defibering  is used.  As a result the  separated fibers are
 removed from the system as  a ; solid  waste,  and  dry  air  pollution
 controljlevices are required to remove fine fibrous emissions from the
 air.   The  costs associated with disposing of the fibrous solid waste
 are deemed minor in comparison with the treatment  costs  required  to
 remove  the fibrous material from the dewatering liquor in cases where
 chemical defibering is practiced.

 Periodically it will be necessary to remove  accumulated  solids  from
 the dewatering liquor storage tank.  It is estimated that these solids
 will amount to less than 15 cubic meters (20 cubic yards)  annually.

 For  those  waste  materials considered to be non-hazardous where land
 disposal is the choice  for  disposal,  practices  similar  to  proper
 sanitary  landfill  technology!  may  be  followed.  The principles set
 forth in the EPA's Land Disposal of Solid Wastes Guidelines (CFR Title
 1*0, Chapter 1; Part 2U1)  may be used as guidance for  acceptable  land
 disposal techniques.          ;

 For  those  waste  materials considered to be hazardous, disposal  will
 require special precautions.   In order to ensure long-term  protection
 of   public  health  and  the , environment,   special  preparation  and
pretreatment may be required prior to disposal.   If land  disposal  is
 to  be  practiced,   these  sites must not allow movement of pollutants
 such as fluoride and radium-226 to either  ground  or  surface  water
                              I
                               169
-------
Sites   Should   be   selected  that  have natural   soil   and geological
conditions to  prevent  such contamination or, if such conditions do not
exis.t,  artificial means  (e.g.,  liners)  must  be   provided   to  ensure
long-term  protection  of  the   environment  from  hazardous materials.
Where appropriate,  the location of  solid hazardous materials disposal
sites   should  be permanently recorded in the appropriate office of the
legal jurisdiction  in  which the site is located.

Pan. iHeaterlt  Mechanicalj, ancl Dry Digestion Rubber Reclaiming

The extent of  the waste water problems  and treatment types  for all dry
reclaiming.processes can best be represented by those of the pan,  or
heater, reclaim process.          |

The  waste water   types  are essentially similar  to those  produced by
Subcategories  E, F, and G plants with the additional  contribution  of
the  oven  vapor  condensates.   The majority of the process wastes are
created by spills and  leaks in  the  cracking,  grinding,  and  milling
buildings  as  well  as  around material and fuel oil storage  areas.  The
contaminants are principally oil and   suspended   solids.    The  vapor
condensates contain   orgahics   Vaporized  from  the rubber mix in the
depolymerization oven.            i

The control and treatment approach  proposed for  this  subcategory  is
isolation  of   the  process  waste  waters  preventing dilution of the
contaminants   and   a   decrease   in   their   treatability.    As   for
Subcategories   E, F, and G wastes,,,  the  key to this type  of  control and
treatment is the reduction and  collection of the contaminated  process
waste  waters   prior to treatment! for oil and suspended  solids removal
in  an  API-type    separator.     The    separable   organics   in   the
depolymerization  oven  condensates can  also  be  separated  in  the
separator.                        !
                                  ]'~ '!.'  "-.' ' -. ''-" "" "  - - ' • - •    	 ™ »'  » .• *••   •?,' '  . • '"  ln
The anticipated effluent quality  ^achieved by the proposed treatment is
presented in Table  25  together with the associated cost data.  In  ad-
dition,   a  detailed description of  the  recommended technology is given
in Section  IX.  Figure 10 is a  schematic flow diagram of the  reguired
control   and   treatment  facilities and is the basis for the indicated
cost estimates.                   !

Treatment Cost Data           "   !

The dry reclaiming industry was reviewed to determine  an  average  or
typical size for a pan process reclaiming plant.   The selected size is
59,000 kilograms (130,000 pounds) ; per day of reclaimed rubber, and the
corresponding   process waste water flow rate is  283,000  liters (75,000
gallons)  per day.   The design flow rate was  supported  by  the  plernt
data obtained  at the reclaiming plant visited.
-------
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Investment2
Annual Costs
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                                                                   171
-------
The  cited  costs are based oh the leases where no treatment facilities
that could be modified  yet  exist,!  and  no  reduction  or  isolation
measures for the containment of contaminated process waste waters have
been  taken.   The design considerations (i.e., the influent raw waste
loads) were selected to represent the expected raw waste  load.   This
results  in  the  generation of cost data which should be conservative
when applied to most of the plants in  this  subcategory.   Relatively
conservative  cost  figures  are  preferred  for  this type of general
economic analysis.                 i.

The capital costs were generated on a unit  process  basis,  with  the
following  "percent  add on" figures applied to the total unit process
costs  in  order  to  develop  the j total   installed   capital   cost
requirements:                      !

                                         Percent of Unit
                                     Process Capital Cost
         Electrical                ;           12
         Piping                    |    .15
         Instrumentation           |            8
         Site Work                 j            5
         Engineering Design and    j
           Construction Supervision1 Fees      10
         Construction contingency  i           15      "

Since  land  costs  vary  appreciably  between plant locations, it was
decided to exclude land cost from tjhe total  capital  cost  estimates,.
Land cost must be added on an individual case basis.

Annual costs were computed using the following cost basis.
          Item

Capitalization

Depreciation


Operations and Maintenance .
Power
    '       .   Cost Allocation
    i
10- percent of investment.

5-yejar straight line with zero
salvage value.

Includes labor and supervision,
chemicals, sludge hauling and dis-
posals, insurance and taxes
(computed at 1.6 percent of the
total capital costs), and main-
tenance (3.2 percent of the total
capi-tal cost)
    i
Based on $0.015 kw-hr for electri-
cal power.
                               172
-------
The  short-term  capitalization • and  depreciation write-off" period is
what is currently acceptable under current  internal  -Revenue  Service
Regulations  pertaining  to  pollution  control  equipment.   Economic
analysis indicates other allowable methods of  depreciation  write-off •
are  more  advantageous.  " The annual costs presented in this document
have.therefore been overstated. | The document.  Economic  Analysis  of
Effluent   Guidelines  The  Rubber  Processing  Industry   (Phase  II),
contains revised annual costs, Reflecting optimum depreciation  write-
off .        .                    |             ' , .  .   •
                                !            ,             •          '
All  costs  were  computed  in  terms  of  August  1973 dollars, which
correspond to an Engineering Hews Record Index (ENR) value of 1920.
                                i                   -.-.-•      ,        .'
Energy Requirements             j

The consumption of power and  energy  by  the  control  and  treatment
system  is minor and is limited !to electrically operated pumps to pump
process waste waters from the point sources within the  plant  through
the  treatment  system.   The  total power needs of the facilities are
approximately 12 horsepower.    |

Nonwater Quality Aspects        !

The primary nonwater quality effect created by the use of the proposed
facilities is the need  for  disposal  cf  oil  and  suspended  solids
collected  in  the  separator.   The  total volume of wastes requiring
disposal is estimated to be 172 ;cubic meters  (230  cubic  yards)  per
year which includes spent coalegcer filters.
                         ;       i
For  those  waste  materials considered to be non-hazardous where land
disposal is the choice  for  disposal,  practices  similar  to  proper
sanitary  landfill  technology  may  be  followed.  The principles set
forth in the EPA's Land Disposal of Solid Wastes Guidelines  (CFR Title
QO, Chapter 1; Part 241) may be used as guidance for  acceptable  land
disposal techniques.            i

For  those  waste  materials considered to be hazardous, disposal will
require special precautions.  In order to ensure long-term  protection
of   public  health  and  the  environment,  special  preparation  and
pretreatment may be required prior to disposal.  If land  disposal .is
to  be  practiced,  these  sites must not allow movement of pollutants
such as fluoride and radium-226 ito either  ground  or  surface  water.
Sites  should  be  selected  that  have  natural  soil  and geological
conditions to prevent such contamination or, if such conditions do not
exist, artificial means  (e.g., liners)  must  be  provided  to  ensure
long-term  protection  of  the  |environment  from hazardous materials.
Where appropriate, the location'of solid hazardous materials  disposal
sites  should be permanently recorded in the appropriate office of the
legal jurisdiction in which the :site is located.
                                  '                                    '
                               173
-------
          subcategories J  and  K  —  Latex-Based Products
                                   .'!''.
          The   latex-based  products   can | be  effectively  separated  into  two
          subcategories.    The  first subclategory (Subcategory J) includes latex
          dipping, latex thread,  and  products manufactured in porous molds.  The
          Subcategory K subcategory consists  of latex foam  manufacture.   Since
          the   required  treatment  is  different  for  the  two  subcategories,
          separate discussions of the cost data are presented,

          Subcategorv J
                                i
         Only one level of control and treatment has  been considered  in  the
         evaluation   of   treatment  effectiveness   versus   cost  data.   This
         recommended  treatment   includes:  chemical   coagulation  and   primary
         clarification of latex-laden wastes  followed by biological oxidation.

         The  biological  treatment  costi  data   have  been based on an aerated
         lagoon and settling pond system. |  The reason  for this  selection  is
         that  the  BOD  concentration in, the process waste waters is typically
         too low to support  an   activated  sludge   type  biomass.   Since  the
         process  wastes  can  be separated  from the utility waste waters, the
         proposed treatment system" is limited to the treatment of  the  process
         wastes.                          '
                                          I
         Treatment Cost Data
         A  profile  was  made  of  the latex dipping industry to determine the
         typical size of a production facility.  The average, or typical, plant
         has a daily consumption of 2,100! kilograms  (4,700  pounds)  of  latex
         sol.ids.   The  associated process waste water flow, derived from pJant
         visit data, is 153,000 liters  (40,000 gallons) per day.
                                         |
         The model treatment plant, consisting of chemical coagulation,  clari-
         fication,  and bio-oxidation is illustrated in Figure 11,  This plant,
         equivalent to BPCTCA, is described more fully in Section IX.
HI
The cited costs are based on the
that  could  be  modified  yet
measures for the containment of
been taken.  The treatment design
correspond  to  the  expected raw
cost figures are preferred for this
 cases where no  treatment  facilities
exist,  and  no reduction or isolation
contaminated process waste waters have
 s upon which the cost data are  based
  waste load.  Relatively conservative
    type of general economic analysis.
         The capital costs were generated
         following  "percent  add on"
         costs  in  order  to  develop
         requirements:
                             figures
                               the
                                 on
    a unit  process  basis,  with  the
     applied to the total unit process
    total   installed   capital   cost
                                         174
-------
                                                                           I
                                                LU


                                                fc
                               «o ac oo
                                                LU>-
                                                o-o:
                                                D-CD
                                                a co
                                                z:=>
                                                LU to
                                                •to
                                                OU.
                                                0.0
                                                Ul
                                                a:
175
-------
                                          i  Percent of unit
                            It: em          Process Capital Cost;

                   Electrical                      20
                   Piping                  !        15
                   Instrumentation         i         8
                   Site Work               I         5
                   Engineering Design  and  !
                     Supervision Construction      10
                   Construction Contingency        15

              Jrea*ment costs incurred by |the  associated technology can  be rep-
         resented  in terms  of  incremental   costs  per  unit   of   production
                 * ,J°™ndata J°r a typical latex diPPin* P^nt  consSng l,™0
                    (4,700 pounds) of  late*  solids per dly indicate  that  the
                                                         kilogram .($0.06?/Ib) of
^
t!
                     costs  vary  appreciably  between plant locations, it was
        r-*n* ^ +  ^xcfude landcost froin t"6 tQtal  capital  cost  estimates.
        Land costs must be added on an individual case basis.          -un«-B.

        Annual costs were computed using the following cost basis:

                  —-                   i -           Cost Allocation

        Capitalization                 10; percent of investment

        Depreciation                   5-year straight line with zero
                                    v  salvage value.

        Operations and Maintenance     Includes labor and supervision,
                                       chemicals, sludge hauling and dis-
f                                      posals, insurance and taxes
                                       (computed at 1.6 percent of the
                                       •total capital costs) , and main-
                                       tenance (3.2 percent of the total
                                       capital cost)

        Power                          Based on SO. 015 kw-hr "for electri-
|                                      cal power.
:                    •                     i    '       >
                                         !   :        "   "."•.""     •
        The   short-term capitalization  and  depreciation write-off period is
        wnat is  currently  acceptable under current  Internal  Revenue  Service
        Regulations  pertaining  to  industrial  pollution  control  equipment.
        Economic analysis  indicates other iallowable   methods  of  depreciation
        write-off  are  more advantageous.   The annual costs presented in this
        document have   therefore  been  oyerstated.    The  document,  EcSnomiS
        Analysis  of Effluent Guidelines  The Rubber  Processing Industry (Phase
        writeoffSlnS revised annual costs,   reflecting  optimum  depreciation
                                          I-
                                        176J
-------
 All   costs  were  computed  in Iterms  of  August  1973 dollars, which
 correspond to an Engineering News  Record Index (ENR)  value of 1920.,
                                •'• _     ,
 The   total  capital  and  annual   costs  for   the   model   treatment
 technologies  are presented for ja  typical latex-dipping plant in Tcible
 26,  together with raw waste load and treated effluent quality.

 Energy Beguirements            |
                   ~            I                         •
.The   primary  clarification   arid    biological   oxidation   treatment
 technologies require  electrical 'energy  only for operation  of  equipment
 such as   pumps   and   aerators.    The  power  needs  are  low and will
 approximate 16 horsepower.      j

 ffonwater Quality Aspects       !
                                I
 The  principal nonwater  aspect iof  the  proposed  technology is  the
 disposal   of  the  primary  coagulated  latex solids' and the infrequent
 removal of  the biological  solidsi from  the  settling   pond.    Both  of
 these wastes will'  be  removed most economically by  contract disposal
 using a vacuum  truck.   The  annual volumes  of  these wastes  will
 approximate:                    i

       Primary Solids:   940  cubic  meters  (1,250 cu yds)
     Biological Solids:   290  cubib  meters  (390 cu yds)

 For   those  waste  materials considered €b be; non-hazardous where land
 disposal is the  choice   for  disposal,  practices  similar  to  proper
 sanitary   landfill  technology  may   be  followed.  The  principles set
 forth in the  EPA*s -Land  Disposal! of  Solid Wastes  Guidelines (CFR Title
 40,  Chapter  1; Part 241) may be used as guidance  for  acceptable  land
 disposal techniques.            i

For   those  waste  materials considered to be hazardous, disposal will
 require special  precautions.  In! order  to ensure  long-term  protection
of    public   health and  the  environment,   special  preparation  and
pretreatment  may be required pribr to disposal.   If land disposal  is
to  be  practiced,  these  sites must not allow movement of pollutants
such  as fluoride and radium-226 to either  ground or  surface  water.
Sites  should be  selected  that  have natural  soil   and geological
conditions to  prevent such .contamination  or,  if such conditions do not
exist, artificial means  (e.g., liners)  must   be  provided  to  ensure
long-term  protection  of  the  Environment  from hazardous materials.
Where appropriate,  the location of solid hazardous materials  disposal
sites  should  be permanently recorded in the appropriate office of the
legal jurisdiction  in which the site is located.
                                !
                               177
                                l"

                                r'
-------
                                        Control and Treatment Technology^
 Investment                |                           $236,700

•   '                       j    -.   :,-    •  •-'.,


Annual Costs              •
                          i             .    •

     Capital Costs        j                             23,700
                          L-                  '    —
     Depreciation         j                             47,300

     Operating and Maintenance Costs                   25,100
     (excluding energy and! power costs)

     Energy and Power Costs                             it6op

Total Annual Costs        '                           $ 96 700
Parameters                ',      Raw Waste              Effluent Quality
kg/kkg(lb/100  Ib)         ;        Loads                	~~	
of raw material si

     BOD                  ;       18.2                      2.20

     Suspended Solids     i       10.90                     2.90

     Oil                  i        0.90                     0.73
                          I  -             '       •'    .•   •
     Chromium        •     j        0.0533                   0.0036
 The control and treatment!technology includes chemical coagulation,
 clarification, biological:oxidation, and secondary clarification,


                           j                           .    -       •

Table 26 - Estimated Waste!Water Control Costs for a Latex Dipped Plant
            (Subcategory J)!
                          i
                          1    178
                          i
-------
 Subcategory K                  •

 Two  levels  of  control   and  -treatment  have  been  studied  in  the
 evaluation  of  treatment  cost land effectiveness.   The first level of
 the proposed technology is chemical coagulation and   clarification  of
 latex-based   wastes,   as   weU   as   chemical    precipitation  and
 clarification of zinc-laden foam rinse waters.   The  second  technology
 level  proposed  involves biological oxidation of the combined primary
 effluents.   The  biological  treatment  cost   data   are  based  on  an
 activated  sludge treatment system.   This type of system was selected
 because  the  BOD loading  of  j  the   combined  effluent   is   high
 (approximately  400 mg/1)  and would be able to support an active mixed
 liquor.   The treatment  cost  is |  also  based   on a   combined  process
 effluent which includes the slightly contaminated barometric condenser
 flows.    This  waste  stream has been included in the cost  evaluation
 because the residual zinc concentration after   chemical  precipitation
 requires  dilution  by  the  condenser  discharge  in  order  to avoid
 biological  inhibition.          i
                                I                                     .
 Treatment £ost Data             j
                                I                     '
 The only significant latex foam 'plant in the United  States was used  as
 a basis  for the industry.   The  plant  has a daily consumption of 68,000
 kilograms (150,000 pounds)  of latex solids; the average process waste
 water flow  is  1,608,000 liters  025,000 gallons) per  day.
                                i
 The  model  treatment plant,  illustrating BPCTCA and BATEA, consists  of
 chemical coagulation of latex solids,  ch,emical  precipitation of zinc,
 and  biological oxidation.   (See  Figure  12.)  This type of plant  is
 described more  fully in Sections'  IX and X.
                              '  i
 The influent raw waste  loads, upon  which the   treatment   designs  are
 based,   represent  the  raw effluent  conditions at the  sole  D.s. latex
 foam plant.  This results  in the  generation of cost data which  are the
 most appropriate for the subcategory  as  it is known to  exist.

 The  total capital and annual costs  for  the model treatment  techniques
 for  the  sole  latex foam plant are presented in Table  27, together with
 the  raw  waste loads and treated effluent qualities.

The  treatment  costs  for  a  latex  foam  production facility can be
 expressed as an incremental costj  per unit  of  production.   The  cost
 data  for a plant consuming 68,OpO kilograms (150,000 pounds) of latex
 *£4d? daily indicate that the BPCTCA and BATEA  treatment  will  cost
 SO.015 per kilogram ($0.0068/lb)! of latex consumption.

The  capital  costs  were  generated on a unit process basis, with the
following "percent add on" figures applied to the total  unit  process
costs   in   order   to  develop;  the  total  installed  capital  cost
requirements:              •     !
                               179
-------
-------
Investment
                                                    Treatment  of  Control Technology
                                                        A                    i
                                                    $348,000              649,000
Annual Costs                            j
     Capital Costs   "                   j
     Depreciation                       j
     Operating and Maintenance Costs    ;
     (excluding energy and power costs) ;
     Energy and Power Costs             j"
Total Annual Costs2
  34,800
  69,600
  55,300

   3.500
$163,200
  65,000
 129,800
  98,400

  13.100
$306,300
Parameters
kg/kkg(lb/1000 Ib)
of raw materials
BOD
Suspended Solids
Zinc -





Technology A is chemical
chemical precipitate and
is Technology A followed
2August 1973.
Raw Waste
Loads!

20.44
8.71 '
3.54
i .
i
i
i
I .
coagulation and clarification of
clarif icationjof zinc-laden waste
by biological! oxidation treatment
; | . .
Effluent Quality
A i

9.43 1.*1
1.60 0.94
0.083 0.083





latex waste waters and
waters. Technology B
•

Table 27 - Estimated Waste Water Treatment Costs' at Different Degrees of Treatment
for a Latex Foam Plant (Subcateeorv K)

!

                                    181
-------
                                 Percent of Unit
                                 Process Capital Cost

          Electrical               j      12
          Piping                         15
          Instrumentation     . •    !       8
          Site Work                ;       3
          Engineering Design and   ,
            Construction Supervisioh
            Fees      ^            |      10
          Construction             i
            Contingency            '      15

 Since land costs vary appreciably i between  plant  locations,  it  wets
 decided  to  exclude  land cost from the total capital cost estimates.
 Land costs must be added on an individual case basis.

 Annual costs were computed using the following cost basis:

          -.£tem_                   !   Cost Allocation	

 Capitalization              10 percent of investment

.Depreciation                5-yearjstraight line with  zero
                             salvage value

 Operations & Maintenance    Includes labor and supervision, chemicals,
                             sludge hauling and disposal,  insurance
                             and taxes (computed at  1.6 percent of
                             the total capital cost), and  maintenance
                             (3,2 percent of the total  capital cost)

 Power                       Based on $0.015 kw-hr for  electrical  power.

 The  short-term capitalization and jdepreciation  write-off   period is
 what  is   currently   acceptable under current Internal Revenue Service
 Regulations   pertaining   to  pollution  control  equipment.    Economic
 analysis   indicates   other allowable methods of depreciation write-off
 are  more  advantageous.   The annual costs presented  in this  document
 have  therefore  been overstated. I  The  document. Economic  Analysis of
 Effluent   Guidelines  The  Rubber ; Processing  Industry  (Phase   II),
 contains   revised annual costs,  reflecting  optimum  depreciation write-
 off a       '                        j                   .

 All  costs  were  computed  in  terms   of  August  1973   dollars,   which
 correspond to  an Engineering News  Record Index (ENR) value  of 1920.
                                   I '' -.".'.:.''
 Energy Requirements                \    '"•'.'

 Energy usage   is related  to the  ne'ed for electric  pumps to  move  waste
 waters through  the treatment  system  and '  for  several  agitator and
                               182
-------
                              '  !         '    ''•-•                 '   '

aerator  systems.   The extra pojwer required for treatment and control
systems is minor and is estimated to be 134 HP.

23onwater Quality Aspects        i
                                i    ...''•-       .
The main nonwater effect of the model treatment system ie the disposal
of the primary chemical treatment solids wastes  and  the  synthesized
biological  solids.   The  most . feasible  ultimate  disposal of these
•filtered and stabilized solid wastes is landfill.  The annual  volumes
of these waters is calculated to! be:
                                !
    Primary Solids:  2,000 cubic meters (1,500 cu yds)
    Biological Solids:  800 cubic meters (600 cu yds)

For  those  waste  materials considered to be non-hazardous where land
disposal is the choice  for  disposal,  practices  similar  to  proper
sanitary  landfill  technology  'may  be  followed.  The principles set
forth in the EPA's Land Disposal! of Solid Wastes Guidelines (CFR Title
>tyO, Chapter 1; Part 241) may be used as guidance for  acceptable  land
disposal techniques.            !

For  those  waste  materials considered to be hazardous, disposal will
require special precautions.  In order to ensure long-term  protection
of   public  health  and  the  environment,  special  preparation  and
pretreatment may be required prior to disposal.  If land  disposal  is
to  be  practiced,  these  sites must not allow movement of pollutants
such as fluoride and radium-226vto either  ground  or  surface  water.
Sites  should  be  selected  that  have  natural  soil  and geological
conditions to prevent such contamination or, if such conditions do not
exist, artificial means (e.g., liners)  must  be  provided  to  ensure
long-term  protection  of  the  environment  from hazardous materials.
Where appropriate, the location !of solid hazardous materials  disposal
sites  should be permanently recorded in the appropriate office of the
legal jurisdiction in which the site is located.
                                !-'."•"'•
Detailed Cost Information for All Subcateaories
   •*———                       .  i             •      .    _

Tables 28 through 43 contain detailed cost information used to develop
the total capital  and  annual  icosts  for  best  practicable  control
technology  currently available :(BPCTCA) and best available technology
economically  achievable  (BATEA)  treatment  systems  presented   and
discussed in Sections VIII, IX and X of this report.
                               183
-------
                          !
          Daily Raw Material Consumption - 900  kg  (2,000  Ibs.)

      Estimated Process  Effluent Flow -= 14,700  L/day  (3,900 gpd)

           -  .      '       j            -I.-..
 Description of Treatment   Facility              Estimated Capital Costs

 Sewer Segregation        ;                            $ 7,200
 Process Sumps and Pumps j                             20,900
 Process Waste Water Force  Main                         1,400
 Filter                   \                              2,300
 Process Effluent Sewer  and Monitoring Station        .10,100

      Sub-Total           i                            $41,900
 Site Work                !                              4,200
• Electrical               !                              6,300
 Piping                   !                              8,400
 Instrumentation          j              „                6.300
      Sub-Total                                       §67,100
                          i
 Engineering Fees                                       6,700
 Contingency              ]                             10.200
      Total Capital Cost  (Investment)2     . .          $84.000
                         . i •  .  .     •     ,	  •. •
   Includes sealing existing floor drains, installation of new process
   drains, and oily waste Water retainment curbing.
 2                      '!                 •
   Land costs are not included.
   ' *  '                    |                   -'••'..-'
                          i                ' .      " .    '
Table 28 - BPCTCA and BATEA Treatment Capital Costs for a Typical Small-
           Sized Molded. Extruded or Fabricated Rubber Plant
           (Subcategorv EO
                          I   184
-------
         Pally Raw Material Consumption « 7,700 kg (17,000 Ibs.)

       Estimated Process Effluent Flow - 75,800 L/day (20,000 gpd)
 Description of Treatment Facility

 In-plant Sewer Segregation
 In-plant Process Sumps and Pumps
 Process Waste Water-Force Main
 Outdoor Waste Water Segregation System
 Outdoor Process Sumps
 Oil Separator
 Filter
 Process Effluent Sewer and Monitoring
    Station

      Sub-Total

 Site Work
 Electrical
 Piping
 Instrumentation

      Sub-Total

 Engineering Fees
 Contingency

      Total  Capital  Cost  (Investment)^
Estimated Capital Costs

       $ 13,900
         31,300
         10,300
          6,300
         10,000
      "   11,100
          4,600

         10.100
       $  97,600

          4,900
         11.700
         14,600
          7.800
       $136,600
         13,700
         20.700

       $171.000
 1
  Includes  sealing existing floor drains, Installation of new process
  drains, and oily waste water retainment curbing.

  Includes  roofing, curbing, and process waste water drains.
  Land costs are not  included.             '
Table 29 - BPCTCA and BATEA Treatment Capital  Costs for a Typical  Medium-
           Sized Molded. Extruded or Fabricated Rubber Plant'
           (Sub category D                '.
                             185
-------
            Daily Raw Material  Consumption = 15,4oO kg (3^,000 Ibs.)

          Estimated Process Effluent Flow = 95,900 L/day (25,300 gpd)


Description of Treatment Facility                     Estimated Capital  Costs

In-plant Sewer Segregation   ;                               $ 22,400
In-plant Process Sumps and  Pumps                             41,700
Process Waste Water Force Maih        2                       17,700
Outdoor Waste Water Segregation System                        11,000
Outdoor Process Sumps        '                                 10,000
Oil Separator    '            '                                  7,800
Filter                   •    |                                  6,900
Process Effluent Sewer and Mopitoring Station                 10,100

     Sub-Total               !                              .$127,600

Site Work                    i                    .              6,^00
Electrical                   i                                 15,300
Piping            t           j                                 19,000
Instrumentation              j                                 10.100

     Sub-Total               i                               $178,^00

Engineering Fees             i                                 17,800
Contingency                  i                                 26.800
                             i                            •   —————

     Total Capital  Cost (Investment)3                       $223.000
 Includes sealing existing flpor drains, installation of new process drains
 and oily waste water retainment curbing.
2
 Includes roofing, curbing, and process waste water drains and sewers.

 Land costs are not included.!
Table 3D - BPCTCA and BATEA Treatment Capital  Costs for a Typical  Large-
           Sized Molded. Extruded or Fabricated Rubber Plant
           (Subcategory G)
                             I  .  '.  •           -  .  . .  :          .   .
                             ;186
-------
          Dally Production Capacity - 54i,000 kg (110,000 Ibs.)

     Estimated Process Effluent  Flow - J392,000 L/day  (.104,000 gpd)


 Description of Control/Treatment Unit  j        Estimated Capital Cost

 Primary Oil Decant  Tank                1              $  8,800
 Waste Oil  Pumps                        j                2*'800
 Waste Oil  Storage Tank                 |                s',900
 Waste Oil  Storage Pump                  !       •         2 800
 Waste Water Storage Tank                j     _          12*700
 Waste Water Tank  Mixer                  !                14*100
 Waste Water Tank  Discharge  Pump         :                4*100
 Waste Water Return  Pump                 !                ] \QQ
 Monitoring Station                      j             _lo!4oO

      Sub-Total                 '         j             $ 63,000
 Site  Work                               !                6f300
 Electrical                              |    ...  .         9f500
 P!Pln9                 v               :               12,600
 Instrumentation                         !     .          -q CQQ

      Sub-Total                '         j             $100,900
 Engineering  Fees                       i               10 100
 Contingency                             i              .15^000
     Total Capital Cost (Investment)1   j             $126.000
                                        I

 Land costs are not included.           I
Tab1e 31 ""PP"* ^.BATEA Treatment Costa for a"Typicd!:ffe
           Rubber Reclaiming Plant    ~           *r—°
           jSubcategorv H)               i
                           187          i
                                        I
-------
                          - I   .    .  - .    ........   .    ,••--.,-' •  ... •-  '
                           i   /,    .:„••,•••-•    -L-,   •   •-  ,,'•,-:,•

            Daily Raw Material Consumption - 59,000 kg (130,000 Ifas.)
                           !      "          *                    '
          Estimated Process';Effluent Flow - 283,400 L/day (74,900 gpd)


 Description of Treatment Facility                  Estimated Capital Costs
                           i
 In-plant Sewer Segregation!                                $  44,600
 In-plant Process Sumps and; Pumps                            28,4-00
 Process Waste Water Force Main        -                     22,500
 Outdoor Waste Water Segregation System                      19,100
 Outdoor Process Sumps     I                                  10,000
 Oil Separator             ,                                  16,500
 Filter                    '                                   6,900
 Process Effluent Sewer and;Monitoring Station               10,100
      Sub-Total            '                                $158,100

•Site Work                 ;                                   7,900
 Electrical                ;                                  19,000
-Piping                    !   .                               23,700
 Instrumentation           !                                  12,600
      Sub-Total            !                                $221,300

 Engineering Fees          i                                  22,200
 Contingency               '                                  33.500
      Total Capital  Cost (Investment)3                     $277.000
  Includes sealing existing!floor drains, installation of new process
  drains, and oily waste water retainment curbing.
 2                         ;
  Includes roofing, curbing,  and process waste water drains  and sewers.

  Land costs are not included.
Table 32 - BPCTCA and  BATEA Treatment Capital  Costs  for-a Typical  Pan.
            Dry Digester or Mechanical Reclaim  Plant
            (Subcategorv I)!
                           j    188.
-------
          Daily Latex Solids Consumption * 2,100  kg  (4,700  IbsJ

      Estimated Process Effluent Flow - 153,000 L/day  (40,000 gpd)
Description of Treatment Unit

Collection Sump and Pumps
pH Adjustment and Coagulant Feed
Mix and Flocculation Tanks
Clarifier
Aerated Lagoon
Aerators
Settling Pond
Monitoring Station

     Sub-Total

Site Work
Electrical
Piping
Instrumentation

     Sub-Total

Engineering Fees
Contingency

     Total Capital Cost  (Investment)
Estimated Capital Cost

      $  7,300
        14,800
         4,700
        18,400
        27,300
        16,600
        36,000
        10.400
      $135,500
         6,800
        26,300
        20,000
        10.800
      $189,400
        is,900
        28.400

      $236.700
1
  Land costs not included.
Table 33 - BPCTCA and BATEA Treatment Capital Costs for a Typical  Latex
           Dipping Production Facility
           (Subcategory J)
                              189
-------
         Daily Latex Soljids Consumption « 68,000 kg (150,000 Ibs)

     Estimated Process EjffJuent Flow - 1,608,000 L/day (425,000 gpd)


 Description of Treatment Unit                     Estimated Capital Cost

 Latex Collection Sump and Pumps                         $  5,800
 pH Adjustment and Coaguilant Feed                           1*200
 Latex Coagulation Tanks;                                   37*500
 Zinc Collection Sump and Pumps                             7*600
 Lime Slurry Tank       j                                    1*600
 Zinc Mixer and Flocculator-Clarifier                      40*000
 Thickener              |                                   41*200
 Vacuum Filter and Solids Handling Equipment               48*500
 Monitoring Station   '].'...                            15*000

      Sub-Total          !                                 $198,400

 Site Work              '                                    a g00
 Electrical              j                                   ^
 Piping                                                    29,900
 Instrumentation
      Sub-Total          |                                $278,000

 Engineering  Fees        i                                  28,000
 Contingency             ]                                  42.obo
                        I            '	
      Total Capital Costs^  (Investment)                   $348.000
 1                       i
 Land  costs are not  included.
Table 34 -  Technology AiCapital Costs for'a Typical Latex  Foam Plant
            (Subcategorv:K)                                 •         "
                             190
-------
         Oafly  Latex  Soltds  Consumption - 68,000

     Estimated  Process  Effluent  Flow » 1,608,000
kg (150,000 Ibs)

L/day (425,000 gpd)
 Description of Treatment  Unit

 Equalization Basins
 Aeration Basins
 Clarlfier
 Thickener
 Aerobic Digester

     Sub-Total

 Site Work
 Electrical
 Piping
 Instrumentation

     Sub-Total

Engineering Fees
Contingency


     Total  Capital  Costs  (investment)1
 Estimated Capital  Costs

        $  85,700
         103,500
         100,400
          22,400
        _ 58.800

        $370,800

          18,500
         44,500
         55,600


       $519,100

         51,900
       - 78.000
       $649.000
 Land costs are not  included.
      35 "  Technology  B Capital Costs  for  W Typical Latex Vc
           (Subcategorv K)I
                             191
-------
                       •  . I.  .

         Dally  Raw Material  Consumption - 900  kg  (2,000  Ibs.)

        Estimated  Process Effluent  Flow • 14,700 L/day  (3,900 gpd)
 Description of Cost  Itemj
                         - i    -
 Absorbent                :
                         i
 Sludge Disposal

 Labor        .    -        j

 Power and Energy         j

 Maintenance              '
                         •]'•
 Insurance and Taxes      j


Total Annual Operating and.Maintenance Cost
Annual Cost

 $   800

     700

   6,300

     600

   3,400

 	L.700
 $13.500
Table 36 - BPCTCA and BATEA Operating and Maintenance Costs  for a Typical
           Small-Si zed Molded..Extruded or Fabricated Rubber Plant
          ''
                            192
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           Daily Raw Material  Consumption' - 7,700 kg (17,000 Its.)

        Estimated Process Effluent Flow -| 75,800 L/day (20,000 gpd)
 Description of Cost Item                i
                                         !
 Absorbent                               i

 Sludge Disposal                          |
                                         !
 Labor                                   j

 Power and Energy                        j

 Maintenance                       .      j
                                         i
 Insurance and  Taxes                     i
                                         i
                                         i
 Total  Annual Operating and Maintenance Costs
$24.000
Table 37 - BPCTCA and BATEA Operating and! Maintenance Costs for a Typical
           Medium-Sized Molded. Extruded or Fabricated Rubber Plant	~
          ISubcategory  F)                ',
                              193
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        Dally  Raw Material Consumption - 15,400 kg  (34,000 Ibs.)

      Estimated Process Effluent Flow « 95,900 L/day  (25,300 gpd)
Description of Cost  Item:

Absorbent                j
                         |
Sludge Disposal   **     '

Labor                    j

Power and Energy         j
                    t     \
Maintenance              !
                         i
                         I               .
Insurance and Taxes      !
                         i
                         i
Total Annual Operating and Maintenance Cost
Annual Cost

 $ 4,900

   3,300

   6,300

   1,200

   8,800

   4.500
 $29.000
Table 38 - BPCTCA and BATEA Operating and Maintenance Costs for a Typical
           Large-Sized Molded. Extruded or Fabricated Rubber Plant
                             194
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         Daily Production Capacity - 54,000 kg (iio.ooo'lb,.)
     Estimated Process Effluent Flow - ^2.000 L/day (,*.000 gpd)
 Description of Cost

 Sludge Disposal
 Labor

 Power and Energy

MaIntenance

 Insurance and Taxes
                                   . i
Total Annual Operating and Maintenance Cbst
Annual Cost

  $ ^,500

    8,800
    4,700

   4,000
   2.000

 §24.000
              S^fnS^^^&i?ii«,c^.for
                           195
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     Dally Raw Mkerlal Consumption - 59,000 kg  (130.000 Ibs.)

    Estimated Process Effluent Flow - 283,400 L/day (74,900 gpd)
                i   ....     ,          .   .  .  .  ,
 Description of Cost Item

 Absorbent      !
                i      -' •              •
 Sludge Disposal |

 Labor          i

 Power and Energy!
                i
 Maintenance            /">
                I
 Insurance and Taxes

                i
Total Annual Operating and Maintenance Costs
TabIC 40 - PPCTCA and BATEA Operating and Maintenance rn«t* *.„ a
           Typical Panf Dry Digester or Mechanical Reclaim Pli^nT"
            u          '                "                '
          (Sub category '!)
                i    •                                                         '.
                !                                           .                  j
                           196
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                         Daily Latex Solids Consumption^ - 2.100 kg  (4,700  Ibs.)

                      Estimated Process Effluent Flow - 153,000 L/day  (40,000 gpd)
                             .          I-  ..„.
 Description of  Cost  Itam              !

   Chemicals                           |

   Sludge Disposal                      i

   Labor                                j

   Power and Energy                     ;

   Maintenance                          j

   Insurance and Taxes                .  I

Total Annual Operating and MaintenanceiCost
                                                                           Annual Cost

                                                                             $ 1,900

                                                                               3,000

                                                                               8,800

                                                                               1,600

                                                                               7,600

                                                                               3.800
                                                                            $26.700
it
                Table kl ~ gPCTCA and BATEA Operating and Hainan,..,
                           Typical  Latex Dipping Production FacTTTtj
                          (Subcatefebtv 'J
                                              197
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         Daily  Lotex Solid^ Consumption - 68,000 kg (150,000 Ibs)

     Estimated  Process Effluent F,ow = ,,608.000 L/day (425.000 gpd)
                           i             .

 Rescript ion of Cost
   Chemicals

   Sludge Disposal

 -  Labor

   Power and Energy

   Maintenance

   Insurance and Taxes
Total Annual Operating and ;Malntenance Cost
                                                              $58,800
                         198
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                                     -   I •  .•'•   •  -     •   :       .  '
        Daily Latex Solids Consumption  j= 68,000 kg  (150,000 Ibs)

    Estimated Process Effluent  Flow = 1;,608,000 L/day  (425,000 gpd)

                                        I          '
Description of Cost I tern                |          /           Annual  Cost
                                        |   ,         .    ,      u -.-.«!! .-!,-,„•,
  Sludge Disposal                       |.                      §   800

  Labor                                 I                        11,100
  Power and Energy .                     ;                         9,600

  Maintenance                           j                        20,800

  Insurance and Taxes                   j                        10.A-00

Total Annual Operating and Maintenance  Costs                   $52,700
Table A3 - ^Technology B Operating and Maintenance Cost for a Typical
            Latex Foam Production Facility (Subcategory K)
                                199
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                              SECTION IX

                 BEST PRACTICABLE CONTROL TECHNOLOGY
              CURRENTLY AVAILABLE - EFFLUENT LIMITATIONS
                              i

General Molded^ Extruded and Fabricated Rubber Subcategories


The  best  control  and  treatment  technologies  currently  in iase at
molded, extruded, or fabricated production  facilities  emphasize  in-
plant  housekeeping  and control measures.  In-plant techniques varied
widely from plant to plant.  In general, they included  the  isolation
of   potential  waste  water  sources  with  retainment  curbing,,  the
elimination of drains in contaminated areas, and the use of  sumps  to
collect  isolated  process  waste  water streams.  The model treatment
technology for a typical plant! is a combination of the  best  features
of  the  various  plants  examined.   It is similar for all three size
subcategories.                i
                              |
Basically, the technology consists of:

    1.   Eliminating anti-tack; or latex solution discharge.
    2.   isolation, control, and treatment of all oily waste
         streams.             j

A flow diagram of the model treatment system is shown in Figure 10.

Previous experience with the tire and inner  tube  industry  indicates
that zero discharge of anti-tack solutions is widely practiced.  Since
this  waste  water  problem  is  common  to  Subcategories E, F, and G
facilities, it is considered a> feasible practice for all Subcategories
E, F, and G facilities to attain zero discharge of anti-tack solutions
by adhering to the following procedures:

    1.   Recycle of anti-tack solution.
    2.   Installation of curbing around the anti-tack dipping
         area.               . :
    3.   Sealing of drains in the dipping area.
    U.   Reuse of the recircuiating system wash water as make-up
         for. fresh an ti-tack solution.
                              i
The reuse of recircuiating system  wash  water  is  the  key  to  zero
discharge  of  this  waste.   In emptying the system for cleaning, the
anti-tack solution should be .stored in tanks.   The  wash  water  used
should  also  be  collected  'and  stored.  Once the system is cleaned,
stored anti-tack can then be returned to the system for use in the new
production batch.  The collection and stored wash water  can  then  be
reused  as  make-up  water  for  the  anti-tack bath during the normal
production run.               ,
                               •201
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Elimination of latex discharges from fabricated products facilities is
achieved by:                     j            •

    1.   The use of curbing -around latex storage and transfer areas..
    2.   The sealing of all drains in latex use areas.
    3.'   The containment of all latex-contaminated waste streams.

It is normal for latex-using facilities to buy latex in bulk and  then
store it in drums as needed, for use within the plant.  The drums nor-
mally  need to be stripped clean of latex after every use.  When water
is  used,  a  waste  water  is  generated.   This  stream  has  to  be
containerized  to  eliminate discharge of latex.  Eowever, it has been
demonstrated that wash waters emanating from this area are  eliminated
when  plastic  drum  liners  are used.  The liners are discarded after
each drum use.
                                 j
Control and treatment of  oily  waste  streams  involves  segregation,
collection,   and  treatment  of ! these  wastes.   The  wastes  to  be
segregated include runoff from oil storage  and -unloading  areas  and
leakage and spills in the process; areas, as shown in Figure 10.  Press
and mill basins, when present, are included in the process area.
                                 i
To  minimize  the raw waste load,] all process water should be isolated
from- the nonprocess waste water  used  in  the  plant.   This  can  be
achieved  by  diverting  drippings from heavy machinery in the molding
and curing areas to sumps.  These,  waste  flows  are  intermittent  by
nature  and,  therefore,  sizeable  flow  rates  will  hardly  ever be
obtained without first collecting all wastes in centralized locations.
Waste waters collected in these sumps will be periodically  pumped  to
an  API-type  gravity  separator,!  where  the separable oil and solids
fraction is removed.  The waste water can  be  either  pumped  to  the
treatment  system or collected in batches and hauled to a treatment or
disposal area.  The latter method should be used only when it is shown
to be unfeasible to rip out and install new sewer lines.

In the medium and large plants, separated oil is  removed  by  a  belt
skimmer.   A  decant  drum is provided to allow water removed with the
oil to settle out.  Concentrated ioil-water mixtures are  then  removed
from the decant tank, drummed, scaled, and disposed of.  Water removed
from  the  tank  is  pumped  back  to  the  separator.  Settled solids
collected in the separator are periodically removed and  disposed  of.
Additional  treatment for oil and suspended solids removal is obtained
by passing the separator effluent through an filter coalescer.  In the
small plants, the waste water flow rates and loadings are  low.   This
allows  the  waste  streams  to be pumped directly from the collection
stunps to  the  filter.   Oil  and  suspended  solids  which  might  be
separated  in  the  sump are manually removed.  The possibility exists
that a high suspended solids loading  may  cause  clogging  of  filter
"coalescers.    In-plant   controls   should  be  capable  of  yielding
significantly lower suspended solids loadings than HO  mg/1,  however.
                               202
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              Set-  S??M-^y  ?  J *     j?     W°Uld be a""00".  Alternatives do
              exist,  strict in-plant controls to prevent oil and grease  spills  and
              leaks  can result  in  compliance with the regulation, or  an  alternative
              treatment system such as dissolved  air  flotation or   dispersed  ail
              flotation can be utilized to  omply with the  limitations.    '
                            manufacturing j hose   via   lead-sheathed   processes,  an
                         parameter,  lead,  can   be  a   significant  pollutant  wiS
             •JSSK^U*?* the plant's waste water effluent.  Lead enters ^curing
             condensate  by being scavanged from  the lead-sheathing; resulting in  I
             JhJ ^Sf™? tration  of  approximately  60 mg/1 within the condense?
             The flow rate of condensate is small, approximately 1  gpm,  therefor^
             gSSSL-'J™**^*  involyr  Segregation  of the condensfte'followel by
             treatment.   other  possible , streams  may also  contain  significant

             watSr  ?f i-i6^- «. TheSe  ?re  th€ lead press and «£*» bSTJSSSj
             Seated    uJSSS Strfams exist they also should  be  segregated  and
             treated.   Methods  of  control  are pre-coat filtration, and recycle
                       C°    9 tOW6r 
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 Effluent quality is best expressed in terms of the waste load per unit
 Qf  raw  material  consumed and is thereby independent of the flow and
 relative size of the plant.  Limitations for BPCTCA are as follows:

 Effluent                         Effluent
 Characteristic                   Limitations
                                  |    .    , •  , .   ' .  .    •„..;..
                     Maximum for  j   Average of daily
                     any one day  j   values for thirty
                                  j   consecutive days
                     	  i   shall not exceed
                                  I     ;     """~"
          (Metric units)    fcq/kkg of raw  material

 Oil and grease          0.70     i       0.25
 TSS                     1.28     i       0.64
 PH                      Within thfe range 6.0 to 9.0.

         (English units)   'ib/IOOOilb of  raw material

 Oil and grease          0.70     '       0.25
 Tss                     1.28     !       0.64
 PH                      Within the range 6.0 to 9.0.   '

 In addition to the  above limitationsf  discharges attributable to  lead-
 sheathed hose production are subject to  the following limitation.
                                  i     .

 Effluent                       .  Affluent
 Characteristic                   Limitations

                     Maximum for  '   Average of  daily
                     any  one day  j   values  for  thirty
                                  •   consecutive days
                     	  i .  shall not exceed

          (Metric units)   Kg/kka  of  raw  material

 Lead                    0.0017   . j       0.0007

         (English units)   lb/1000 lib of  raw material

 Lead                    0.0017    i       0.0007

 For  plants utilizing wet scrubbers,  an additional allowance for TSS is
 as  follows:                       ]

 Effluent                         Effluent
Characteristic              :     Limitations
                                  i -  ", ,      . ,   .........
                               204 I
-------
                              Maximum for
                              any one day

                                         !
                                    Average of daily
                                    values for thirty
                                    consecutive days
                                    shall not exceed
          TSS
          TSS
                    (Metric units)
                   (English units)
                          kg/kkg of raw material
                               equivalent
                        5.8
           2.9
                          Ib/1o6o ib'of raw material
                               I equivalent
                        5.8
  i
2.9
          Only one of the two small plants visited is  currently  achieving  the
          standard  for  oil.   Both small plants are achieving the standard for
          suspended solids.               |

          Subcategory F;  Medium-Sized Production Facilities

          The  control  and  treatment  technologies  are  compatible  with  the
          following thirty day average effluent quality for medium-sized molded,
          extruded and fabricated rubber  production facilities:
t
                   Suspended Solids
                   Oil and Grease
                   Lead
                   pH
                                          i
                                        HO mg/1
                                        15 mg/1
                                       0.1 mg/1
                                        6.0 to 9.0
It  is  expected  that  the  use of an API separator will result in an
effluent oil concentration of approximately 30 mg/1  (possibly  higher
concentrations   should   be   damped  by  secondary  oil  and  grease
treatments).  The use of a filter coalescer should further reduce  the
effluent   oil   concentration jto  15  mg/1.    Literature  on  filter
coalescers indicates that 15 mg/1 is readily attainable.  A  reduction
of  suspended  solids  to  40  mg/1 will result from the use of an API
separator.  Additional reduction appears likely after passage  through
the filter coalescer.

                         expressed
           Effluent quality is best
           of   raw material  consumed and
           relative size of the plant
      in terms of the waste load per unit
   is thereby independent of the flow and
Limitation for BPCTCA are as follows:
           Effluent
           Characteristic
                              Maximum  for
                              any one  day
                                 Effluent
                                 Limitations

                                    Average of daily
                                    values for thirty
                                         205
-------
                                     consecutive days
                                     shall  not exceed
          (Metric units)    kg/kkg of  raw  material
                                i.      -
Oil and grease           0.42    !         0.15
TSS                      0.80    |         0.40
PH                       Within the range 6.0 to 9.0.

        (English units)    lb/1000 lb of  raw material
                                |      -    ;  -     ........ ^ ....       ..
Oil and grease           0.42    j         0.15
TSS                      0.80    j         0.40
PH                       Within the range 6.0 to 9.0.

In addition to the above limitations, discharges attributable to lead-
sheathed hose production are subject to  the following limitation.

                                i                         .           .  '
Effluent                        I Effluent
Characteristic                  | Limitations

                    Maximum for \     Average of daily
                    any  one day j     values for thirty
                                ;     consecutive days
                    	 |     shall not exceed

         (Metric units)   kq/kkor of  raw  material

Lead                     0.0017  i         0.0007

        (English units)   lb/1000 lb of  raw material

Lead                     0.0017  j         0.0007
                                i
For plants utilizing wet scrubbers,  an additional allowance for TSS is
as follows:                     i

Effluent                        iEffluent
Characteristic                  j Limitations

                    Maximum for ;    Average of daily
                    any one day     values for thirty
                                    consecutive days
                    	     shall not exceed

         (Metric units)  -kg/kkq: of raw material
                               equivalent
                                1       /"  . *
                        5.8     i         2.9
                                1

                             206'
                                I
                                i
-------
        (English units)   lb/1000 Ib of rawmaterial
TSS
        5.8
All the  medium-sized  plants
standard  for  both  oil  and
analysis conducted by the EPA
Subcateggry
  equivalent

          2.9

 visited  are  currently  achieving  the
 suspended solids (according to saimpling
contractor).
Large-Sized Production Facilities
The  control  and  treatment  technologies  are  compatible  with  the
following  thirty day average effluent quality for large-sized molded,
extruded and fabricated rubber production facilities:
          Suspended Solids
          Oil and Grease
          Lead
          PH
                        40 mg/1
                        15 mg/1
                       0.1 mg/1
                        6.0 to 9.0
Effluent quality is best expressed in terms of the waste load per unit
of raw material consumed and is thereby independent of flow  and  size
variations  within  the  overall  size  subcategory.   Limitations for
BPCTCA are as follows:       !
Effluent
Characteristic
                    Maximum for
                    any one day
                 Effluent
                 Limitations

                    Average of daily
                    values for thirty
                    consecutive days
                    shall not exceed
         (Metric units)   kg/kkg of raw material
Oil and grease
TSS
PH  '
        0.26 ;           0.093
        0.50.i           0.25
        Within the range 6.0 to 9.0.
        (English units)   lb/1000 Ib of raw material
Oil and grease
TSS
PH
        0.26 j           0.093
        0.50 \           0.25
        Within the range 6.0 to 9.0.
In addition to the above limitations, discharges attributable to lead-
sheathed hose production are subject to the following limitation.
                             i  207
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 Effluent                          [Effluent
 Characteristic                   , idmita tipns

                     Maximum for  j    Average of daily
                     any one day  j    values for thirty
                                      consecutive days
               .      - •        i    shall not exceed

          (Metric units)   kcr/kkg  of  raw maters

 Lead                    0.0017   I        0.0007

         (English units)   lb/1000 ib of Taw ,.»<.«„.< -,-i

                         0.0017   j        0.0007

                          scrubber!s'  an  additional allowance  for TSS  is
 Effluent                         ^Effluent
 Characteristic                   limitations

                     Maximum for  :   Average of daily
                     any one day  i   values for thirty
                                  !   consecutive days
                       .           I   Shall not exeegfl

          (Metric units)    kg/kkq tof raw material
                        - "      equivalent

 TSS                      5.8   •   i       2.9

         (English units)    lb/lP^plib_of_raw_material
                                 equivalent

 TSS                      5.8             2.9
                                   , .,, ,   .„„,   ,

    JJjqestion BeclajLmed Rubber  Suhcateaory

identification of Best Practicable Control  Technol
Currently Available    :           |~^ -- -
^vdi^Sti°nvrUbber f6013101^? is  a  declining industry and  currently
only  three  known  plants  remain.   The  wet  digestion  process  is

          yaSi°Ut Wl   S0me°
oocoht              '    the Wet    ges     r
production being taken up by the  dry ^reclaiming processes
                              208 !
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 Of the  existing  wet  digestion  plants,  all  except  one  discharge
 contaminated   process  waste  waters   to  local  municipal  treatment
 systems.  The one  exception  utilizes  a  waste  stream  recycle  and
 reclaim  system  which  appreciably  reduces  the waste water loadings
 prior to direct discharge.  This plant  is currently  undergoing  plaiU
 to also discharge to a municipal treatment system.

 Only  minor  waste  water  quality improvements can be achieved by the
 good housekeeping and waste control because the greatest proportion of
 waste water contamination is generated  by the dewater ing- liquor  waste
 stream and not by spills, leaks, and washdowns.

 Limitations for BPCTCA are as follows:
 Effluent
 Characteristic
                     Maximum for
                     any one day
                                 Effluent
                                 Limitations

                                    Average of daily
                                    values for thirty
                                    consecutive days
                                    shall not exceed
          (Metric units)   kcr/kka of pro duet
COD
Oil and grease
Tss        .
PH
                        14,7  _           6
                         0.40   !         0
                         l.OU   !         0.52
                         Within the range 6.0 to 9.0.
                      •
         (English units)    lb/1000 Ib of
TSS
PH
    and grease
                         O.SO   !         0.1W
                         1.04   :    .     0.52
                         Within .the range 6.0 to 9.0.
 Pan fHeaterl .  Mechanical and Dry Digestion
7 Reel aimed Rubber
 Identification of Best Practicable Control Technology
 Currently Available            !
            *                    I           '          '           •
 Currently,   the most common method of treating wastes from  Subcategory
 I  reclaim facilities is to discharge to municipally operated treatment
 systems.   In-house efforts tc control the pollution-producing   aspects
 of  the   facilities  have  been;  directed  mainly toward air emission
 problems.   Water pollution problems have not been considered  a major
 problem.    Therefore,   the proposed treatment technology for a  typical
 Subcategory I  reclaim  plant  is   the  same  as  that used  in lather
                             209!
-------
industries having similar waste water problems.  It is very similar to
the  technologies proposed for  Subcategories. E, F, and G.

As before, the technology employed consists basically of:

     1»   Eliminating anti-tack solution discharge.
     2»   Segregation, control  and treatment of all oily waste.

The  flow diagram is the same  as presented for Subcategories E, F, and
G and is presented in Figure 10.  The  anti-tack  solution  discharges
are  eliminated by recycling.   Wash;waters are also reused.  Oily waste
streams  are  segregated, collected and treated.  Segregation involves
blocking  existing  drains  in contaminated  areas   and   installing
retainment  curbing.  Once segregated, the waste streams are collected
in sumps.  The waste water is  treated  in  an  API  separator  and  an
filter  coalescer  medium.   For a detailed discussion of the proposed
system, refer to the related paragraphs dealing with 'Subcategories  E,
ff and G.                          '                  .

Effluent Loadings Attainable with the Control Technology

Based on the control technology obtained from reclaim sources and data
obtained  from  industries  having  similar  waste water problems, the
control and treatment technologies\ are  deemed  compatible  with  the
following  thirty  day  average effluent quality for pan (heater), dry
digester or mechanical reclaim facilities.
                                   ;                         ••                    j
          Suspended Solids               no mg/1
          Oil and Grease           i      30 mg/1
          PH
6.0 to 9.0
It is expected that the use of an API separator and a filter coalescer
will result in an effluent oil concentration of 30 mg/1.   The  higher
concentration  of  oil and grease allowed for rubber reclaiming is due
to the use of light soluble oils utilized in rubber reclaiming.

A reduction cf suspended solids to 40 mg/1 will result from the use of
the API separator.  Additional reduction appears likely after  passage
through a filter coalescer.

Effluent  limitation  for BPCTCA, expressed in terms of waste load per
unit of raw material consumed are as follows:

Effluent                         Effluent
Characteristic                   Limitations

                    Maximum .for     Average of daily
                    any one day    : values for thirty
                                    consecutive days
                    	     shall not exceed
                             210

                                   :            .             :•              ;  ;   i
-------
          (Metric units)   kg/kkg of product

 Oil and grease          0.40            0.14ft
 TSS                     0.384  ;         0.192
 PH                      Within the range 6.0 to 9.0.

         (English units)   lb/1000 lb of product
 Oil and grease         '0.40            c
 TSS                     0.384           o!l92
 PH                      Within the range 6.0 to 9.0.

 The following COD limitations may apply to  pan,  dry  digestion,  and
 mechanical  reclaimed rubber processes integrated with a wet digestion
 Effluent                         Effluent
 Characteristic •                  Limitations

                    Maximum for     Average of daily
                    any one day     values for thirty
                                :     consecutive days
                    		shall not exceed

          (Metric units)    kcr/kka of product

                         6.7   ' '•         2.8

         (English units)    lb/1000 jb of  product

                         6.7             2.8


 Subcateaories  j and K — Latex-Based Products

 The principal  difference in the :waste water characteristics  found  at
 i^6XZ   e*    manufacturing  facilities    and   those  of  the  other
 subcategories  studied in this document, is  the presence of substantial
 quantities of  uncoagulated  latex  solids in  Subcategories J and K waste
 waters Subcategory J plants include  latex-dipped goods, latex  thread,
 and  products  made  in  porous   molds.   The  one latex foam plant in
 existence constitutes Subcategory K.                          P^HC. in

 Subcategory J

All latex-bearing waste waters should be  passed  through  a  chemical
—"—-  and  clarification  primary  stage of treatment.  In this
            i                                               .
f£^fs th?,J-a^ef " coagulated to form  solid  rubber.   Treatability
studies  will determine whether a "sinker" such as clay is required to
                              211
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weight, down -the coagulated solids or whether their buoyancy will allow
them to be skimmed from the clarifier.

The first unit of this treatment is a rapid mix tank where  the  waste
water  pH  is  adjusted  to  facilitate  coagulation.  The coagulating
chemicals, alum and polyelectrolyte are added to the tank.   The  tank
contents  are  vigorously  mixed  to  bring  together  the coagulating
chemicals-  and  the  latex  solids.   Waste  water  then  flows  to  a
flocculation tank where the coagulation process is completed with mild
mixing  in  order  to  create  a separate solids floe.  The mixture of
flocculated solids and waste water passes to the clarifier  where  the
coagulated  solids separate from the waste water.  If a "sinker", such
as clay, is required the solids will  settle  to  the  bottom  of  the
clarifier  where they can be drawn off, and the clarifier waste stream
will overflow.  If, on the other hand,  the  latex  solids  float  and
separate  readily,  the  coagulated  latex  will  be  skimmed from the
surface of the clarifier and the clarified waste water will  underflow
from clarifier.                  i

The  most  practicable technique for disposing the small quantities of
coagulated  latex  solids  resulting  from  this   treatment   is   by
contracting . for  the  transport  of  the  residual  wastes to a final
disposal site.  In the case of the sinking solids these can be  pumped
from  the  clarifier to a sludge dewatering bed from where they can be
collected periodically by the disposal contractor.   For  the  skimmed
latex  solids,  the skimming can be first passed to a screen where the
bulk of the water is removed and returned  to  the  treatment  system.
The screened solids can then be containerized.       .

The  clarified  waste stream passes from the clarifier into an aerated
lagoon where it  is  mixed  with  biological  solids.   Microorganisms
synthesize  new biological solids; from organic matter contained in the
waste water.  At the same time, some soluble matter  is  consumed  for
energy  purposes  using oxygen supplied by the aerators in the lagoon.
The net result is that soluble  matter  is  converted  into  insoluble
biological  solids which can be separated from the waste water thereby
reducing the soluble BOD of the waste water.  Treatability studies and
waste water analyses will  determine  if  the  nutrient  addition,  if
necessary, can be made in the rapid mix tank.

The mixture of waste water and biological solids in the aerated lagoon
overflows  from  the  lagoon  to  a settling pond* where the biological
solids settle out and additional biological stabilization of the waste
water occurs.  The settled solids; are removed periodically, say  twice
a  year,  from  the  pond.   The  most feasible and practicable method
involves the.  employment  of  a  contract  haulerfs  vacuum  truck  or
equivalent  'apparatus.   The  clarified  waste water from the settling
pond overflows to an effluent  monitoring  station,  where  the  waste
water  flow, temperature, and .pH are recorded and .an automatic 24-hour
composite sample is collected.   ,  '
                               212:
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A biological treatment  system  composed  of  an  aerated  lagoon  and
settling  pond  is proposed for Subcategory J facilities since the BOD
levels in this waste water are too low to support a  good,  settleable
biomass  in  an  activated  sludge  treatment  facility.  The proposed
treatment is illustrated schematically in Figure 11.

The above description discusses primarily the treatment of latex-laden
wastes.   Non-latex  waste  waters  which   require   only   secondary
biological  treatment,  such as product rinse waters, should be routed
to the aerated lagoon, bypassing  the  coagulation  and  clarification
system.   This  approach  will , enhance  the treatability of the latex
wastes and reduce the size of coagulation-clarification facilities  by
preventing unnecessary dilution.

It  should  be  noted  that  the latex-laden wastes can be reduced and
potentially eliminated by careful housekeeping and good latex handling
practices.  Excessive washdown jand cleaning waters should  be  avoided
when  dealing with latex spills.  Latex spills can often be coagulated
in situ, with alum or other coagulants, and removal as a solid mass by
shoveling and scraping.  Plastic drum liners can be used to  eliminate
pollutants  from  entering the waste waters during drum cleaning.  The
benefits, in treatment costs and effluent quality,  created  by  these
and other techniques are appreciable.

A  few  latex-dipping  operations  generate waste waters which require
additional control and treatment techniques.  These techniques are not
included in the cost data presented in Section VIII since they are not
representative of the processes: used by the  majority  of  the  latex-
based manufacturing facilities.:  Form-cleaning wastes, such as chromic
acid-laden   rinse   waters,  should  be  eliminated  by  the  use  of
alternative cleaning techniques believed to be feasible in almost  all
cases.   If  the  chromic  acid cleaning technique cannot be replaced,
then chromium chemical  reduction  and  precipitation  procedures  are
required.

SubcateqorY £

The BPCTCA treatment for the latex foam industry is based on the waste
water  characteristics  and  treatment  approach  of the only existing
latex foam plant.  Briefly the  model  treatment  system  consists  of
chemical  coagulation  and clarification of latex-bearing waste waters
and  chemical  precipitation  of  the  zinc-laden  rinse  waters   and
biological treatment.

All  latex-laden  wastes can be, isolated and sent to a chemical coagu-
lation and clarification system.  The system  consists  of  two  dual-
purpose  coagulation  and ' clarification tanks.  The tanks are filled,
treated, and settled alternatively in a batch-wise manner.  The  latex
wastes  are  first adjusted manually for pH using acid and alkali feed
systems and then-dosed with coagulating chemicals  such  as  alum  and
                             213
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polyelectrolyte.  The coagulated latex solids are allowed to separate.
Treatability  studies will ascertain whether a "sinker"f such as clay,
is required.  Floating latex solids can 'be skimmed from the water  and
screened.   The  filtrate  water  from  the  screen is returned to the
treatment system, and the screened solids are collected and hauled to a
final disposal site.  During the  entire  coagulation,  settling,  and
emptying  -process  the  second  identical  tank  is  on-line and beinq
filled.

Zinc-laden rinse waters are treated in another  system  simultaneously
to  the  latex-laden  wastes.  The 'zinc wastes are pumped to rapid mix
tank where lime and polyelectrolyte are added  under  vigorous  mixing
conditions.   The  pH  of the waste water is raised and the solublized
zinc is precipitated as insoluble zinc hydroxide.  • The  precipitation
process  is  concluded in a flocculation tank where the zinc hydroxide
and lime solids agglomerate under  mild  agitation."   The  flocculated          f
waste water flows to a clarifier where the zinc sludge settles out.             1

The clarified waste water is discharged with the clarified latex waste          I
waters  to  a  neutralization tank where the pH of the combined wastes          \
are adjusted to the acceptable range for biological treatment (6.0  to
9.0 units).                        !

The  zinc-lime  sludge is pumped to a holding tank prior to dewatering
on a vacuum drum filter.  The filtrate is returned to the mix tank and
the filtered sludge is containerized prior to final disposal.

The performance of the latex  waste  water  treatment  system  can  be
improved  with  good housekeeping a!nd handling procedures as described
for Subcategory J industries.      !

Effluent Loadings Attainable with the Control Technology

Subcategory J                      ,

Based  on  raw  waste  load  and  control  and  treatment  data   from
Subcategory J plants, it was determined that the control and treatment
technologies  can  achieve  the  following thirty day average effluent
qualities:

         BOD                            30 mg/1             I
         Suspended Solids          i     40 mg/1
         Oil                            15 mg/1
         Chromium                  ;      0.05 mg/1
         pH           f            '     6.0 to 9.0

The chromium limitation is included to ensure that those plants  using'
chromic  acid  form-cleaning  techniques  do  not  discharge,  chromium
containing wastes without adequate treatment.
                              214
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 The effluent waste loads resulting from the application  of  treatment
 technologies equivalent to chemical coagulation with clarification and
 biological  treatment,  constitute  the  best  practicable control and
 treatment standards currently available for SubSategory  J.   Effluent
 limitations for BPCTCA are:                                   *ii.Luent
Effluent
Characteristic
                    Maximum for'
                    any one day
                                  Effluent
                                  Limitations

                                     Average of daily
                                     values for thirty
                                     consecutive days
                                     shall not exceed
          (Metric units)    kg/kkg of raw material
 Oil and grease
 BOD5
 TSS"
 pH
                        2.0    i         0.73
                        3.72            2.20
                        6.96   .;         2.90
                        Within the range 6.0 to 9.0.
         (English units)    lb/10QO  lb of  ra«
 Oil  and grease
 BODS
 TSS
 pH
 limitatin
                        2.0             0.73
                        3.72    ;         2.20
                        6.96    ;         2.90
                        Within the range 6.0 to  9.0.

                 the   above  limitations,  discharges  attributable to
                 cleaning  operations are subject  to  the  following
Effluent
Characteristic
                                Effluent
                               ' Limitations
                    Maximum for
                    any one day ',
         (Metric units)   kg/kkg
Chromium
                        0.0086
                                   Average of daily
                                   values for thirty
                                   consecutive days
                                   shall not exceed

                                .of raw material
                                       0.0036
        (English units)   lb/100!0 lb of raw material

Chromium                0.0086  i      .  0.0036
                               215
-------
         Subc ateqory K
HIM
        -The  raw  waste  load and control and treatment data obtained from the
         only operating latex foam plant indicates that the recommended  BPCTCA
         control   and   treatment   technologies  for  latex  foam  production
         facilities are  compatible  with  the  following  thirty  day  averciae
         effluent quality:                                                   y
                   BOD
                   Suspended Solids
                   Zinc
                   pH
                                           60 mg/1
                                           40 mg/1
                                           3.5 mg/1
                                           6.0 to 9.0
         This effluent quality can also be expressed in terms of effluent waste
         loads  which  are independent of waste water flow and dilution.  These
         effluent waste loads, resulting  from  the  application  of  treatment
         technologies  equivalent  to  chemical  treatment and clarification of
         both latex and  zinc-laden  waste  waters  and  biological  treatment,
         constitute  the  best  practicable  control  and  treatment technology
         standards  currently  available  for  the  latex   foam   subcategory.
         Effluent limitations for BPCTCA are:   !
         Effluent
         Characteristic
                             Maximum^ for
                             any one day
                                 Effluent
                                 Limitations

                                  ,  Average of daily
                                  :  values for thirty'
                                    consecutive days •
                                    shall not exceed
          (Metric units)   kq/kkg of raw material

Zinc                    0.058           0.024
BOD5                    2.4       !      1.4
TSS                     2.26      :      0.94
PH                      Within the range 6.0 to 9.0.

        (English units)   lb/1000 ,lb of raw material

Zinc                    0.058     ;      0.024
BOD5                  .2.4       ;      1.4
TSS                     2.26 '    i      0.94
PH                      Within the range 6.0 to 9.0.
        Variability Factors               :    -

        For  all  pollutant   parameters   the daily  maximum  is  greater than the
        monthly average.  The ratio of daily maximum to monthly average is the
                                          216
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variability factor.  Available long-term data on the operation, of  the
designed  treatment  systems   (within the rubber and other industries)
were  statistically  analyzed.    Using   2.3   standard   deviations,
variability   factors   were   derived   for  pollutants  within  each
subcategory.
                               217
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                              SECTION X

         BEST AVAILABLE TECHNOLOGY  ECONOMICALLY ACHIEVABLE -
                         EFFLUENT LIMITATIONS


General Molded, Extruded. and Fabricated Rubber Sufccategories

Effluent limitations on oil and suspended  solids  applicable  to  the
best available technology economically achievable  (BATEA) and the best
practicable   control  technology   currently  available   (BPCTCA)  are
identical  for  general  molded,  extruded,  and   fabricated   rubber
subcategories.    BPCTCA   treatment  reduces  the  prime  pollutants,
suspended solids, oil and grease,   and  lead  to  such  a  level  that
further  treatment cannot be justified on a technical, cost or benefit
basis.                         .        .

Complete water reuse or  elimination  of  contaminated  waste  wsiters,
leading  to zero discharge, is not  universally feasible.  Treatment of
the waste water to approach influent-supply water quality in  a  reuse
or  recycle  system  requires removal of oils, suspended solids, total
dissolved solids, and trace contaminants that cannot be  substantiated
on   a   technical,  benefit,  or   cost  basis.   Some  small-capacity
manufacturing facilities (where the process waste water flow is  small
and slightly contaminated)  can eliminate direct discharge to navigable
waters  by  contract disposal or discharge to municipal systems.  This
will most probably be the most economic approach and will avoid costly
discharge monitoring and reporting  procedures.

Effluent Loading Attainable with Control Technologies

Limitations and standards for BATEA are identical to those for  BPCTCA
with  the  exception  of the limitations for wet scrubbers.  For BATEA
wet scrubbing waters should be recycled and the blowdown settled prior
to discharge.  The BATEA limitations for wet scrubbing waters shall be
as follows:

Effluent                         Effluent
Characteristic                ;   Limitations

                    Maximum for     Average of daily
                    any one day     values for thirty
                              ,      consecutive days
                    	.	.	i     shall not exceed

         (Metric units)    kg/kkg of raw material
                              1eguivalent

TSS                     i.'o   :          0.5
                             219
-------
          (English units)    lb/1000 j.b^of raw

                                 equivalent



- TSS                     1-0 '      :      0.5


  Wet Diqestign_Reclaimed  Rubber^
                       611* involves "cycling of  waste  water  streams
                 «    Process  oils.   The  proposed  modification  is
             schematically in Figure 9 (Section VII).

 In a conventional wet digestion reclaiming process,  the  devulcaniz«=.<3


         -'                            Ljg:f?
 The dewatering liquor is sent to an agitated storage tank  from  which

 it can be pumped back to the digestion make-up process?
                   The decant tank is equipped with  an  overflow
                                          "                  °-
 The recovered oils  and organics  from  the  decant tanks are  sent  to  a

















 streams  and  to suspend rubber fines and prevenTthS? sStifng lT2£
digestion process without the recycle system.         generated  by  CL



Effluent Loadincis Attainable with Control Technologies     '. '
                            220
-------
 Further  treatment  of   effluent  waste  waters   beyond  BPCTCA is not
 considered  economically  achievable  by  this  economically  marginal
 segment  of   the  rubber industry.   Future changes in the profit margin
 of reclaimers may warrant reevaluatidn, however, at  this  time  BATEA
^limitations  shall be  equivalent to BPCTCA limitations.
       -IHeaterlj    Mechanical ^    and  Dry  pigestj.on  peel aimed  lubber
 Subcategory

 For this  subcategory, the  effluent  limitations  recommended  for  the
 best  available  technology economically  achievable are identical to
 those for the  best practicable technology currently available.

 Although  it is not feasible to recycle or reuse entirely  the  process
 weiste  waters,  direct  discharge to navigable waters can be eliminated
 by employing the local  municipal treatment system for the discharge of
 those waste waters which   wou^d  benefit  from  secondary  treatment.
 Contract  haulage of contaminated waste is not generally feasible since
 the volumes involved in this industry are considerable.

 Latex-Based Products

 Subcategory J

 Waste  water  pollutants are substantially reduced by BPCTCA.  Further
 reductions of  COD  may be possible, however indications  are  that  the
 effluent   COD  from biological treatment of  latex dipped, molded,  and
 extruded  plants  may be   less  than  that  for  the  Latex  Subcategory
 (manufacture of  latex rubber)  after carbon adsorption-.  Unless further
 information   is  obtained, justifying  additional  treatment  on  an
 environmental  and  economic basis, BATEA shall be equivalent to BPCTCA.

 It is possible in   some cases  to  reduce the  effluent  loading  by
 applying   good- housekeeping and materials-handling procedures, such as
 the containment  and reduction  of latex washdown waters;   however,  the
 extent of  the  effect of these  measures  cannot  be  anticipated.
 Municipal systems  can be used  to treat the residual  contamination  of
 the  process wastes, thereby eliminating direct discharge to navigable
 waiters.                        ;                   .

 Subcategory K

 The BATEA treatment (equivalent to EPCTCA)  for  the latex foam industry
 is based  on studies made by the^ only operating  latex foam plant in  the
 industry.    In  brief,   it  involves  biological  treatment  using  an
 activated sludge process.   The activated sludge process  is selected in
 this  instance  since   it  is the most feasible  and economic biological
 treatment approach (based  on the high BOD loading of latex foam  waste
 waters   after  primary   treatment) .    The   treatment   system  is
 schematically  represented  in Figure 12.           -      .
                             22]
-------


                     1±quor
                                    settled in the secondary clarifier

A drum-type vacuum filter separates thickened sludge into:
                                                 l>elt  conveyor  to  a
2.
         A filtrate that 'is recycled to the neutralization basin.
                              222 ,
-------
The dewatered sludge cake is biologically stable and can  be  disposed
of  to  a  sanitary landfill.  Filter aid and precoat tanks, pumps and
metering equipment may be required to assist and maintain the  quality
of the filtrate.                          •              ;

Effluent Loading Attainable with Control Technologies

Currently,  there  is  only one known latex foam plant.  This plant is
negotiating to be  permitted  to  discharge  to  a  municipal  system.
Further   analysis   of   technology   beyond   BPCTCA  is  considered
unnecessary,  it is doubtful that new  plants  will  be  built,  other
latex  foam plants have existed, but were economically forced to close
mainly from polyurethane completion.  If  other  plants  do  begin  to
manufacture  latex foam, a reevaluation cf both BPCTCA and BATEA would
be warranted.  Process differences  and  plant  size  would  be  major
factors to reconsider.                                  ;
                              223
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                               SECTION XI


                    NEW-SOURCE PERFORMANCE STANDARDS
 Effluent_Limitatiohs          |

 General Molded^ Extruded^ and Fabricated Rubber Subcategories

                        for  new  sources  are  identical  to  the best
                           With  8tri<*er  limitatons  aAd  ts
               w?^^St£iCter "•f^j™-   Some new plants?      as"
               will  not  be  economically capable of achieving further

                       cfiS£ha-9e' '5* theref^e-  ^ generaT feSSiS
                       can be imposed upon new sources.

 Wet Digestion Reclaimed Rubber Subcategory

 Technological  and  economic  restraints  resulting from air and water
 pollution problems point to  the  eventual phasing  out  of  the   wl?

 SSriSeP2TSf;p,J?00rdin9 t0 industry ^kesman,  no new  facilitSs
 using  the wet digestion process are planned  for  the future.   In fact

 lo   chan^ieS*-USi^ th€ Pr°CrS either  have  a^«ady chafed  or plan
 A^corS^^fv    2  thS  Pan'* dry  di9estion»  or   mechanical  process?
 Accordingly,  new-source performance  standards shall be   equivalent  to
 best   practicable   control  technology currently available     N^W
                 n                                      the
           or mechanical  process.
    JHeaterl^. Mechanical^  and ^y. Digestion Rubber Reclaiming

Effluent  limitations  for new  sources  are  identical  to  the best
£5° ^bJ^°ntr01 technolo5Y Currently available?   ?hese  standards
SSo^ii Jff   I1?  are  Presented in section IX of this report.  NO new
process alterations are known at this time which would  enable  a  new
source to achieve stricter limitations.

Latex-Based Products Subcateaory
          1imitfJi°nf  f°r  Subcategory  J  and  K,  new  sources  are
             ^the  beSt  Practicable  control  technology   currently
 X os rennJ^6  *tandards and limitations are presented in Section
wWoh «^?^  P ^*     new Process alterations are known at this  time
which would enable a new source to achieve stricter limitations.
                              225
-------
 gretreatment Recommendations
                                     ** giV6n t0 «ew Production  facil-
                                                            -a-ent

 Iron,
        Molded,. Extruded and fabricated Rubber Products Subcategories

                      for Process waste waters from  Subcategories  E
get Digestion Reclaimed Rubber  Subcateqory

             C0ntf01f for Process  waste  waters  from  Subcategory  H
                                                                '
                                               «~'»  fr -
                                    'to  Di^stion geclaimed  Rubber

                             226
                                                                             fe
-------
Latex-Based Products Subcatecrory

Reconunended pretreatment of process waste waters  from  Subcategory  J
and  Subcategory K facilities include coagulation and clarification of
solids-laden waste water.  In addition, precipitation  procedures  are
required to remove any chromium in Subcategory J waste waters and zinc
in Subcategory K waste waters.
                              227
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                            SECTION XII



                          ACKNOWLEDGMENTS                  .      .





 Inc  °WestnCh  dl"aft  °f  th1S  document was PrePared by Roy F.  Weston.



 DaJld0^"*96^^
The  Environmental  Protection  Agency  wishes  to   acknowledae "  th*

"SfSJl dnH°f fhe°ff1ce:s  and Plant penSSl In the rSbblr Indus 2?

U£r£«      Valu!ble/ss1stance 1n the collection of data relating to
process  raw waste  load and  treatment plant performance at

rubber processing facilities.  Special aclcnowlIdgEtS 2d!
                            .   ,
                        '
                                                         ,
         s±a
                           229
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                             SECTION XIII                 ,

                         GENERAL BIBLIOGRAPHY

Shreve, R.N;, "Chemical Process Industries," CPI", New York:  McGraw-
Hill, "Inc., 1967.

Standen, A. ed., "Kirk-Othmer, Encyclopedia of Chemical Technology;
Vol»  17", New York:  John Wiley and Sons, 1968.

•"Rubber Industry Facts", New York:  Rubber Manufacturers Association,
1972.

"Air  Flotation-Biological Oxidation of Synthetic Rubber and Latex
Wastewater".  Lake Charles, Louisiana:  Firestone Synthetic Rubber
and Latex Company, October 15, 1972.                                          |

Rostenback, R.E., "Status Report: on Synthetic Rubber Wastes."  sewage
and Industrial Waste, Vol. 21, No. 9, September  1952, 1138-11U3.

Placek, O.R. and Ruchhoft, C.C., "A Study of Wastes from the Synthetic
Rubber Industry."  Sewage and Industrial^Waste, Vol. 18, No. 6,
November  1946, 1160-1181.       :

Martin, A.E. and Rostenback, R.E., "Industrial Waste Treatment and
Disposal."  Industrial  and Engineering Chemistry, Vol. «t5. No. 12,
December  1953, 2680-2685.                                 !

Dougan, L.D. and Bell,  J.C., "Waste Disposal at  a Synthetic Rubber Plant."
sewage and Industrial Wastes, Vol. 23, No. 2, February 1951, 181-187.

"A Study  of Pollution Control Practices  in Manufacturing Industries."
Marketing Services Division, Research Services Department* Dun and
Bradstreet, Inc., Jufie  1971.

Hebbard,  G.M., Powell,  S.T.  and Rostenback, R.E., "Rubber  Industry'".
Industrial  and Engineering Chemistry, Vol. 39, No.  5, May  1947,  589-595.

Nemerow,  N.L.,  "Theories  and Practices of Industrial Waste Treatment",
New York:   Addison-Wesley Publishing  Co., 1963.

Alliger,  G.  and  Weissert, F.C., !"Elastomers."  Industrial  and
Chemistry,  Vol.  59,  No. 8, August  1967,  80-90.

Montgomery,  D.R.,  "Integrated System  for Plant Wastes Combats  Stream
Pollution."   Chemical  Engineeriag. Vol.  63, No.  Ht  February  1967,
 108-110.                                                  ;

Ruebensaal,  C.F.,  "The Rubber.Industry Statistical  Report and  Changing
Markets and Manufacturing Patterns  in the Synthetic Rubber Industry."
                               231
-------
     New York:   International Institute of Synthetic  Rubber  Producers,  Inc.,
     1972.

    ^Hofmanri, W.,  "Vulcanization and Vulcanizing Agents",  New York:   Palmerton
     Publishing  Co.,  Inc.,  1967.                           .

     Hawley, G.G.,  "The Condensed Chemical Dictionary",  New  York;  Reinhold
     Co.,  1971.                            ;

     Lund,  H.F., ed., "Industrial Pollution Control Handbook", New York:
     McGraw-Hill,  Inc., 1971.

     "Methods for  Chemical  Analysis  of  Water and Wastes."  Environmental Pro-
     tection Agency,  National Environmental Research  Center,  Analytical Quality
     Control Laboratory, Cincinnati, Ohio, 1971.
         »                            .    i
     Taras, M.J.,  ed.. Standard Methods for the Examination of Water  and
     Wastewater; American Public~Health Association,  Washington, D.C.,  1971.

     Water; Atmospheric Analysis, Part  23, "Standard  Method  of Test of  Bio-
     chemical Oxygen  Demand of Industrial  .Water and Industrial Wastewater."
     1970 Annual Book of ASTM Standards, American Society  of  Testing  and
     Materials, Philadelphia, -Pennsylvania,  1970.

     Eckenfelder,  W.W., "Industrial  Water  Pollution Control", New  York:
     McGraw-Hill,  Inc., 1963.

     "Rubber Products Handbook,  Molded, Extruded Lathe Cut, Cellular",  3rd ed.,
     Rubber Manufacturers Association,  December 1970.

     "Sheet Rubber Handbook,  Gasket  and Packing Materials",  2nd ed.,  Rubber
     Manufacturers Association,  September  ;1968.

     "Hose Handbook", 3rd ed.,  Rubber Manufacturers Association, October 1970.

I     Noble, E.E. and Amendole,  G.A., "Zinc Removal from  A  Rubber Reclaiming
.;     Operation", unpublished  internal B.F.  Goodrich report to James Lewis.

|     Perry, J.H.,  ed., "Chemical Engineers•  Handbook", 4th ed., New York:
\     McGraw-Hill,  Inc., 1963.
:                                          ,.,._,.          ;
     Water Quality Criteria 1972. National Academy of Sciences
     and National Academy of  Engineering for the Environmental
     Protection Agency, Washington,  D.C. 1972 (U.S. Govt.  Printing
     Office, Stock No. 5501-00520) .        '.
                                   232
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                              SECTION XIV

                                GLOSSARY

 Accelerator Agent:

 A compound which greatly reduces  the time required for vulcanization of
 synthetic or natural  rubber.

 Act

 The Federal Water  Pollution Control  Act,  as Amended.

 Activator                                                    '

 A metallic oxide that makes possible the  crosslinking  of  sulfur  in
 rubber vulcanization.

 Antioxidant                    '

 An organic compound added to  rubber  to retard oxidation or  deterioration.

 Anti-tack Agent

 A substance used to prevent rubber stocks from sticking together during
 periods of storage.
Bag House
                              •v
An air emission control device used to collect intermediate and large
particles  (greater than 29 microns) in a bag filter.   (A bag filter
constructed of fabric.)  Common usage in the industry  is to control and
recover carbon black in a dry state from vapors leaving the compouridina
area.                          :

Banbury Mixer

Trade name for a common internal mixer manufactured by Farrel Corporation
used in the compounding and mixing of tire rubber stock,
Best Available Demonstrated Control Technology

Treatment required for new sources as defined by Section 306 of the Act

Best Available Technology Economically Achieyable^BATEA^

Treatment required by July 1, 1983 for industrial discharges to surface
wctters as defined by Section 301  (b)  (2)  (A) of the Act.
                             233
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                                         SrentlvAyailable
 Treatment  required bv
 waters as  delined  ^
 BOD5                     .     .     ]
                                    I
 Biochemical Oxygen  Demand  (5 day) .
                                                                to surface
                                          Polymerization of isobutylene
  Camelback
  Tire tread used in the retreading of tire carcasses.
  Cagitaijcosts                      I
                                                              i
  Financial  charges  in August 1971  dcllaT-« «h,-~K
  of  capital times the capital expendi£urL 5    *tf comPute<3 as the cost
  of  capital is assumed to £ iJS            Pollution control,   cost
                                                        oonpolklds
 garbon Black
 A reinforcing agent used in large ^antities in
at
 Cement
                                                ">* «-»- * to proceed
                  consisti^ of polymeric rubber solids dissolved in
                °r  ^^egation  of  previously e^sified partides into a
COD     .                             i
Chemical Oxygen Demand.                    -
Crumb               ••''.'
small coagulated particles' of synthetic rubber.
                              234
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 Curing Agents                   !

 Curing or vulcanization agents are substances which bring about the
 rubber cross linking process.   The most important agent is sulfur.
 vulcanization.)

 Depreciation    -                ',

 Accounting charges  reflecting  the deterioration of  a capital asset over
 its  useful life.  Reported as  straight line over five years with a:ero
 salvage value.                  '.

 Devulcanization

 The  term is used to describe the  softening  of a vulcanizate
 by heat and chemical additives during  reclaiming.  -

 Pry  Air-Pollution Control       !                   -

 The  technique of air pollution abatement without the use  of water.

 Emulsion                        •'

 A stable mixture of two or more immiscible  liquids held in suspension by
 small  percentage of substances called  emulsifiers.

 Endogenous Respiration

 Auto-oxidation of the microorganisms producing a reduction and stabilization
 of biological solids.

 EPDM

 A synthetic rubber based on ethylene-propylene and a controlled amount
 of non-conjugated diene.   Polymerization is carried out in solution.

 Extender                                             .-..'.

 A low specific gravity  substance used in rubber  formulations chiefly to
 reduce costs.

 Extrude                         |                         :

To shape by forcing a material through a die.  The operation is carried
 out in a device kncwn as an extruder.
A high specific gravity (2. 00-4. ,50)  compound used in rubber mixtures to
provide a certain degree of stiffness and hardness and used to decrease
                               235
                                                                             L
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costs.  Fillers have neither reinforcing or coloring properties and are
similar to extenders in their cost-reducing function.

Flash                              ;

The overflow of cured rubber from a mold.          -         |
Gallons per minute.

IR                              .   :                         .       .

Poly isoprene rubber, the major component of natural rubber, made syn-
thetically by the solution polymerization of isoprene.
                                   [
Investment Costs

The capital expenditures reported in August 1971 dollars required to
bring the treatment or control technology into operation.  Included are
expenditures for design, site preparation, purchase of materials, con-
struction and installation.  Not included is the purchase of land on
which the system is to be built.
Liter

Iiatex

A suspension of rubber particles in' a water solution.  Coagulation of
the rubber is prevented by protective colloids.  A protective colloid is
a surface-active substance that prevents a dispersed phase of a .suspension
from coalescing by forming a thin layer on the surface of each particle.

Masterbatch                        !

A compounded rubber stock applicable to a wide variety of uses.  Main
ingredients are rubber, carbon black and extender oil.

mcr/1                               '                         :

Milligrams per liter.              :

                                   i
Modifier                                                    '.     "     -

An additive which adjusts the chain length and molecular weight dis-
tribution of the rubber during polymerization.
                              236
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 Monomer
 NBR
 New Source
 after the publication of   e
 Non-Produff^.ive_Rubber Stock
Hon-React.ive_Rubber  Stock
Operations and
PER
              rUbber' a
BE

lower pH indicates acidiy;
Pigment
                                            e"ttlslon
                                                                    of
                                                            iS
                                c rubber «aae by soiution I polymerisation
                                                                    •
                                             indicates alkalinity and a
                             237
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 Plastic                            ;         •

 Capable of being shaped or molded with or without the application of
 heat.

 Process_Water

 All  waters that  come  into  direct  contact with the raw materials and inter-
 mediate products.

 Productive Rubber Stock

 Compounded rubber which contains  curing agents and which can be vulcan-
 ized.   Synonym for reactive rubber stock.

 Raw  Material  Equivalent

 The  term raw  material  equivalent  shall  be equal to the raw material
 usage  multiplied by the volume of air scrubbed via wet scrubbers
 divided by the total volume of air scrubbed.           -    '  ,

 Reactive Rubber  Stock               '

 Compounded rubber which contains  curing agents and which can be vulcan-
 ized.   Synonym for productive rubber stock.
                                   '"'.'.•         -   i
 Reclaimed Rubber                   ;                         i

 Depolymerized (plasticized) scrap rubber, either natural or synthetic.

 Reinforcers or Reinforcing  Agents

 Fine powders  used to increase the  strength, hardness and abrasion
 resistance of  rubber.  Reinforcing agents used in the rubber processing
 include carbon black, zinc  oxide, and hydrated silicas.

 Rotacure                            ;

 Trade name for a common curing press;

 SBR               .                                      .

 Styrene butadiene rubber.  A synthetic rubber made either by emulsion or
 solution  polymerization of styrene and butadiene.

Soapstone

A substance used to prevent rubber stocks from
 sticking  together during periods of storage.  Used in both a dry and
 solution form.  The major ingredient is usually clay.
                              238
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          Solution                                                ;

          A uniformly dispersed mixture at the molecular  level  of  one or more
          substances in one or more other substances.

          Stripper           .            :
                                   <     •    " •                    r

          A device in which relatively volatile components  are  removed from a
          mixture by distillation or by passage of steam  through the  mixture.
          A division of a particular industry which possesses  different traits
    «     which affect water quality and treatability.

          Surface Waters                                        "

          The waters of the United  States  including the territorial seas.

          Vulcanization

'          Vulcanization is the process  by  which plastic rubber is converted into
'          the elastic rubber or hard rubber  state.   The process  is brought about
/          by linking of macro-molecules at their reactive  sites.

          Wet Air-Pollution Control

          The technique of air pollution abatement  utilizing water! as an
          absorptive media.
                                        '239
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                                     TABLE 44
                                  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/rninute       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
 ton (short)             ton
 yard                   .yd
 * Actual  conversion,  not a multiplier
0.405
1233.5
0.252
0.555 :
0.028
1.7 i
0.028
•28.32 ;
16.39
0.555(°F-32)*
0.3048:
3.785
0.0631
0.74571
2.54 ;
0.03342
0.454
3,785
1.609 :
i
(0.06805 psig +1)*
0.0929
6.452
0.907
0.9144.
ha
cu m
kg cal
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

atm
sq m
sq cm
kkg
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
klllowatts
centimeters
atmospheres
kilograms
cubic meters/day
kilometer

atmospheres (absolute)
square meters
square centimeters
metric ton (1000 kilograms)
meter

                                         240
                                                          * U.S.WVW»«IOtT nHimie CTOL117$- 582-421/255
-------