EPA-600/2-77-136
July 1977
Environmental Protection Technology Series
AUTOMATIC EXCHANGE RESIN PILOT PLANT
FOR REMOVAL OF TEXTILE DYE WASTES
Industrial Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
-------
RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental Protec-
tion Agency, have been grouped into nine series. These nine broad categories were
established to facilitate further development and application of environmental tech-
nology. Elimination of traditional grouping was consciously planned to foster technology
transfer and a maximum interface in related fields. The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the ENVIRONMENTAL PROTECTION TECHNOLOGY
series. This series describes research performed to develop and demonstrate instrumen-
tation, equipment, and methodology to repair or prevent environmental degradation from
point and non-point sources of pollution. This work provides the new or improved tech-
nology required for the control and treatment of pollution sources to meet environmental
quality standards.
REVIEW NOTICE
This report has been reviewed by the participating Federal Agencies, and approved for
publication. Approval does not signify that the contents necessarily reflect the views and
policies of the Government, nor does mention of trade names or commercial products
constitute endorsement or recommendation for use.
This document is available to the public through the National Technical Information
Service, Springfield, Virginia 22161.
-------
EPA-600/2-77-136
July 1977
AUTOMATIC EXCHANGE RESIN PILOT PLANT
FOR REMOVAL OF TEXTILE DYE WASTES
by
Allison Maggiolo and J. Henry Sayles
Bennett College
Greensboro, North Carolina 27420
Grant No. R803455-01
Program Element No. 1BB610
EPA Project Officer: Max Samfield
Industrial Environmental Research Laboratory
Office of Energy, Minerals, and Industry
Research Triangle Park, N.C. 27711
Prepared for
U.S, ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, D.C. 20460
-------
ABSTRACT
The use of an automated bench scale pilot unit employing adsorption resins
to remove colored dyes from textile dye wastes, and also permit the reuse and
recycle of its effluent has been realized in this study. At the same time ap-
proximately 50 + 10% of .the BOD and COD was concurrently removed from these
same dye wastes.
This adsorption resin pilot unit was adequately sized and automated to
operate continuously at flow rates which enabled the realistic calculation of
costs and design of a commercial plant to remove these dyes. For 20,000 gals/
day dye waste (a typical size for most individual hosiery dye plants), the es-
timated capital costs would be $86,000 and operating costs would be $9,430/yr.
This is equivalent to an amortized operating cost of $3.47/1000 gals, of dye
bath wastes. These costs are competitive to those for three other competing
processes for treatment of dye wastes: ozonation, carbon treatment, or hyper-
filtration (reverse osomosis). Operating costs for these processes are appro-
ximately $1.90, $1.00 and $2.00 per 1000 gallons, respectively on a one million
gals/day rate of operation. These costs would be equal to or exceed the esti-
mated costs for the resin adsorption process when scaled down to the typical
20,000 gals/day dispersed dye hosiery plant basis. A key factor that favors
this adsorption process over the other three, is the proven effectiveness in
removing insoluble dispersed dyes from wastewater. The alternate processes are
reported to effectively remove soluble dyes in textile wastes, however, little
has been reported on how efficient they are in removing the relatively insolu-
ble dispersed dyes. These insoluble dyes are non-responsive to biological
waste treatment processes. Disperse dyes, in the amount of about 50 million
Ibs/yr. are used to dye man made fibers (polyester, polyamides, acetates and
acrylics). More dispersed dyes are in use today than any other type.
This report was submitted in fulfillment of Project No. R-803455-01 by
Bennett College, Greensboro, North Carolina under the sponsorship of the U.S.
Environmental Protection Agency. This report covers the period April 1, 1975,
to February 28, 1977, and work was completed as of April 15, 1977.
11
-------
CONTENTS
Abstract ..... ii
Figures ..... ... iv
Tables vi
Abbreviations and Symbols .,- .. vii
Acknowledgments Viii
1. Introduction — — 1
2. Conclusions 3
3. Recommendations 5
4. Experimental Procedures .... 6
Preparation of Ion-Exchange Resins 6
Automation 6
Still for Methanol Recovery 8
Color Removal 8
COD & BOD 9
5. Discussion and Results 10
General 10
Hanes Disperse Dye Wastes 11
Glen Raven Disperse Dye Wastes 15
Hanes Acid Dye Wastes 22
Sellers Reactive Dye Wastes 22
Comparison of Technical Efficiencies and Costs
with Other Dye Removal Processes 22
Capital and Operating Costs - Adsorbent Resin Process ... 25
Capital and Operating Costs - Ozone Process 26
6. References 45
7. Appendices 46
8. Glossary 54
111
-------
FIGURES
Number Page
1. The automatic bench scale pilot unit 27
2. Pictorial wiring diagram 28
3. Sketch of bench scale pilot unit, each column containing
a different adsorbent resin in series 29
4. Sketch of bench scale pilot unit, each column containing
the same adsorbent resin in series 30
5. Semi-continuous stripping still 31
6. Main colors, Glen Raven disperse dyes 32
7. Hanes disperse dye waste, color photo showing complete
removal of color after 120 BV, same resin 33
8. Hanes disperse dye waste, % color removal vs bed
volumes treated 34
9. Hanes disperse dye waste, % COD removal vs bed volumes
treated 35
10. Hanes disperse dye waste, % Color and COD removal vs
bed volumes treated (2 columns, XAD-7 and A-7) 36
11. Glen Raven disperse dye waste, color photo of color
removal 37
12. Glen Raven disperse dye waste, % color removal vs bed
volumes treated 38
13. Glen Raven disperse dye waste, % BOD removal vs bed volumes
treated 39
14. Glen Raven disperse dye waste, % COD removal vs bed volumes
treated 40
15. Hanes acid dye waste, color removal, color photo of color
removal 41
16. Hanes acid dye waste, % color and GOD removal vs bed
volumes treated 42
-------
17. Sellers reactive dye waste, color photo of color removal 43
18. Sellers reactive dye waste, % color removal vs bed
volumes treated 44
-------
TABLES
Number Page
1. Hanes Disperse Dye Waste (2XAD-7 Columns) 12
2. Hanes Disperse Dye Waste (XAD-7 followed by A-7 Column) 15
3. Glen Raven Disperse Dye Waste (XAD-7 followed by A-7 Column 16
4. Hanes Acid Dye Waste (one A-7 Column only) 23
5. Sellers Reactive Dye Waste 24
Vl
-------
LIST OF ABBREVIATIONS AND SYMBOLS
ABBREVIATIONS
Abs — absorbance
BOD — biochemical oxygen demand
BV — bed volumes
bv/hr — bed volumes per hour
COD — chemical oxygen demand
ml — milliliters
MGD — million gallons per day
ppm — parts per million
P.S.~1 — pressure switch number one
P! — pump number one
SS — suspended solids
TOC — total organic carbon
Vi — valve number one
SYMBOLS
H20 — water
MeOH — methyl alcohol
03 — ozone
vii
-------
ACKNOWLEDGEMENTS
The authors are Indebted to Seymour G. Hall, originally of Cone Mills
and now of Chemionics Industries who provided valuable background informa-
tion and made available his doctoral dissertation, "The Adsorption of Dis-
persed Dyes on Powdered Activated Carbon".
The advice and assistance of Mr. Ellis Pardue, Manager of Environmental
Health & Safety Services and his staff, Central Research and Development,
Hanes Corp., in expeditiously supplying the plant dispersed hosiery dyes which
enabled us to obtain the cost engineering data necessary for completion of
this project is greatly appreciated. A useful contribution was made by Mr.
William Simpson, Manager of Dyeing, Glen Raven Hosiery Mills, who not only
provided all the initial dispersed plant dye exhaust samples, but also ren-
dered invaluable technical assistance related to dispersed plant dyeing opera-
tions.
The assistance given by Howard Dixon, Manager of Dyeing, Sellers Manufac-
turing, in supplying all the various waste samples containing non-dispersed
dyes is gratefully acknowledged.
A major contribution was made by Dr. Dale Chidester of Rhom and Haas who
assisted in the initial phases of the project and finalized the diagrams and
special equipment for the automation of the Bench Scale Automatic Pilot Plant.
Also, the assistance of Mr. Chester P. Fox, P. E., Manager of the Fluid Pro-
cesses Dept., Rhom and Haas, was invaluable in supplying their exchange resins
along with scale up design and engineering knowledge that resulted in optimiz-
ing the cost engineering represented in this report.
The assistance given by William F. Dixon, Cplorist, Ciba-Geigy, Dyestuffs
& Chemical Div., was most useful in confirming the actual chemistry and chemi-
cal structures of the dyes involved in these dye wastes.
Special thanks are due to Dr. Max Samfield, Project Officer, whose con-
tinued helpful technical advice supplied the essential costs of potential com-
petitive proceses (granular activated charcoal, ozonation and hyperfiltration).
This enabled presentation of a meaningful economic comparison of the adsorp-
tion resin process compared with the alternate processes as a means of decolor-
ization of dye wastes. Also appreciated was the foresight and encouragement
rendered for this Project by Dr. Willie Ashley and Mr. Clyde Bishop, Office
of Monotoring & Technical Support, EPA, Washington, D. C.
viii
-------
SECTION I
INTRODUCTION
BACKGROUND
One of the major problems faced by the textile industry is the pollution
of streams by dye wastes. Previous laboratory research, "Application of Ex-
change Resins for Treatment of Textile Dye Wastes , Report No. EPA - 660/75-
016, Project No. R80-2586 had shown the potential feasibility of the applica-
tion of polymeric exchange resins to remove colored dyes from textile dye
wastes. Among the vast array of industries contributing to the pollution of
our environment, textile mills are perhaps the most conspicuous. Not only are
their discharges characterized by persistent and obnoxious colors, but also by
high concentrations of BOD, COD, TOC, SS. Elevated temperatures, extreme pH
and substantial levels of heavy metals (e.g. chromium, copper, zinc) also are
typical of these effluents. The discharge of intensely colored industrial
wastes into natural waters immediately brings to one's attention a deteriora-
tion of the aesthetic quality of these receiving waters. However, thr"ee less
obvious but equally important effects also result from color pollution. (1)
The presence of light absorbing compounds decrease light penetration and hence
the rate of production of oxygen by photosynthesis. The net result can be an
oxygen deficiency accompanied by a loss of marine life and algae growth. Be-
cause of this relationship the EPA is seeking to limit the discharge of color
pollutants into natural waters at levels which cause less than a 10% change
in oxygen production by photosynthesis vs oxygen production by respiration.1
(2) Color substances also chelate metal ions. This phenomenon increases both
the cost of water treatment and the probability of contaminants of heavy met-
als. (3) The condensed aromatic polyringed color compounds which usually
contain nitrogen are generally highly toxic and are suspect carcinogens, par-
ticularly so after the usually standard post chlorinated treatment by most
municipal plants. For these reasons the EPA has proposed that color in water
before treatment be less than 75 APHA2 color units, and perhaps quite less,
in terms of micrograms per liter because of later toxic findings as related
to halogenated polyringed structures.3»4
OBJECTIVES
The same chemistry that gives fabric colorfastness and resistance to
bleaching, sunlight, and oxidation makes these dyes similarly resistant to
clean-up processes that depend upon degradation (BOD, chlorination, and even
at times the ozonation of dispersed dyes) as a means of decolorization.
The objectives of this study is to demonstrate an automatic bench scale
pilot unit using polymeric resins to remove dyes from textile wastes. The
-------
size and flow rates of the unit will be appropriately sized to obtain the ne-
cessary data to ascertain costs and technical feasibility of a full scale re-
sin exchange.
In the latter studies of this project our Project Officer, Dr. Max
Samfield, suggested that we show an economic comparison between ion exchange
resins (this study) vs granular activated charcoal, ozonation and hyperfil-
tration as a means of decolorization. Under separate cover he has supplied
us with the essential cost data of the latter three technologies (see Appen-
dices), thus providing the basis for a cost comparison as a further objective
of this project.^
-------
SECTION II
CONCLUSIONS
Removal of color from dispersed dyeing wastes by adsorption resin tech-
nology is a practical and effective procedure. Capital and operating costs
for such a process are favorable when compared to other proven processes,
viz: activated charcoal, ozonation, and hyperfiltration. This is especially
so in that the resulting effluent appears to be reusable and can be recycled
in the same plant dyeing operation.
This finding is relevant to dispersed dye wastes since the particular
type of macroreticular polar adsorption resins used herein were tailored to
efficiently adsorb the surfactant and dispersants that held the colored dis-
persed dyes in suspension. Thereupon these dyes readily become agglomerated
and attracted by Van der Waals forces to porous surfaces of the resin.
The findings showed that 120 bed volumes of dyeing wastewater could be
passed and decolorized before the resin bed had to be regenerated. At least
five cycles of regeneration were accomplished with no decrease in adsorption
efficiency of the resin. The most efficient arrangement, representing~the
lowest capital and operating costs, was when two XAD-7 type resin beds were
used in a "flip-flop" sequence in series. The projected capital cost is
$86,500. Operating costs, including amortization, for this arrangement to
remove the color from 20,000 gals/day of hosiery plant dye wastewater would
be $3.47/1000 gals. Ozonation at the same processing rate (20,000 gals/day)
would require capital costs of $55,000 and an amortized operating cost of
$3.21/1000 gals. The other two processes, carbon treatment and hyperfiltra-
tion, are impractical because of technical difficulties with Disperse dye
wastes.
Disperse dye waste removal is important because these nonsoluble type
of dyes are either non or only partially biodegradable refractory compounds
which pass through biological treatment systems relatively unchanged. Use
of dispersed dyes, similarly for dyeing man-made fibers (polyester, poly-
amides, acetates and acrylics), totals 50 million pounds plus per year. More
dispersed dyes are used than any other type.
Though disperse dyes are effectively removed by the Adsorption Resin Pro-
cess, the other three competitive processes have almost solely reported on
soluble dye removal rather than insoluble dispersed dyes. The reasons for
this situation are technical limitations inherent in each of the processes:
(1) Hyperfiltration- easy clogging of small membrane pores with suspended
dispersed dyes with extra maintenance and energy usuage; (2) Carbon treat-
ment has been reported to be not effective for dispersed dye removal; (3)
Ozonation- assuredly a build up of decolorized oxidized dyes and additives
which may impair continuous reuse and recycle of effluent and which when
purged to the wastewater environment will have an increased BOD.
-------
Finally, a unique practical advantage is that the relatively non-
aqueous highly concentrated BOD and COD oily dye waste from the resin pro-
cess can be readily burned as fuel at the plant site while the other three
processes still have to dispose of the dilute aqueous polluted BOD and COD
dye waste by more expensive methods.
-------
SECTION III
RECOMMENDATIONS
It is suggested that a typical textile mill using dispersed dyes be the
site of a Demonstration Resin Adsorption Plant to treat colored dye waste
effluent for reuse and recycle in a closed loop system.
In particular a hosiery dyeing plant should be selected where there is
currently an active program going on to both remove waste dyes and reuse the
resulting effluent instead of discharging said wastes into a municipal treat-
ment plant which is not prepared to handle this type refractory wastes.
It is suggest that such an arrangement be considered and explored with a
textile company that has several similar hosiery plants in the Southeast using
dispersed dyes, which would be applicable to the same technology of treating
their colored dye wastes and reuse of the resulting effluent.
It may be valuable to demonstrate and evaluate the amortized operating
costs of the ozone vs the resin adsorption process using the same Disperse
dye waste.
-------
SECTION IV
EXPERIMENTAL PROCEDURES
PREPARATION OF ION-EXCHANGE RESINS
Some ion-exchange resins require little pretreatment if any. In some
cases the pretreatment of the resins are specific only to the application.
For example, the treatment of an acid dye waste influent is bes^t accom-
plished by alkalizing Duolite A-7, which is shipped in its hydrochloui.de salt
form, with one bed volume of 5% sodium hydroxide solution at 5 bv/hr followed
similarly with a water rinse. The sodium hydroxide treatment of the resin is
replaced with 5% sulfuric acid, when the influent is basic.
XE-275 was pretreated by the following method in all applications. The
resin was soaked in water and transferred to columns by the slurry method.
XE-275 used in our work was shipped in its weak basic form.
The pretreatment of XAD-7 in all application is accomplished by soaking
the resin in methanol and transferring it to columns by slurry methods. The
resin bed was expanded 50% with a water backwash for a minimum of ten minutes.
The bed was allowed to settle and was ready to accept the influent dye waste.
AUTOMATION
The automatic bench scale pilot unit, Figure 1, was designed to ascertain
the cost and technical feasibility of a full scale resin exchange plant to re-
move textile dye waste. Plans for the unit were made after careful discussion
with engineers of Rhom and Haas and using several related reference reports.
The consideration for minimal standards to obtain appropriate data to be able
to scale up findings to plant size are: the resin bed in the columns must be
at least two feet high, minimum diameter of column = one inch, and a flow rate
of at least four bed volumes per hour. Experimental conditions were set at
bed height of three feet and flow rate at 4 bv per hour.
Rimex beaded glass pipes, four feet long by one inch (i.d.) coupled with
industrial flanges to reducing glass tube fittings were used as columns.
The automatic control equipment used was composed of the following com-
ponents :
Stepping Switch, Model 2420, Tenor Company
Multi Range On-Delay Reset Timers, Model 551, Tenor Company
Ten Multi Head Metering Pumps, Model 7189, Cole Palmer Company
Automatic Solenoid Switching Valves, Automatic Switching Company
-------
Universal 3-Way Valves, Red Hot, No. 832043
2-Way Valves, Red Hot (NC) No. 8262C6
Pictorial Wiring Diagram, shows the electrical circuits to the above
equipment to automatic lly oarry out the 22 steps of the operation, Figure 2.
Automation 1
Steps of Automation of Bench Scale Unit for 2 columns of different
resin material. The following refer to Figure 3.
Step 1 Removal of Dyes and Additives in Dye Waste—
P! (pump 1) starts dye waste by P.S.-l (safety pressure switch) through
column 1, V3, V^, column 2, Vs, Ve to effluent.
Step 2 Rinsing of Resin in Column 1 (C-l)—
P! stops. ?2 starts H20 through V£, Vi, column 1, V3, to Semi-Continuous
Stripping Still or Used Regenerant.
Step 3 Regeneration of Resin in Column 1 (C-l)—
V2 changes. Methanol is pumped by P£ through V2, Vi[, column 1 to Semi-
Continuous Stripping Still or Used Regenerant.
Step 4 Rinsing of Resin in C-l—
V2 changes. H20 is pumped by ?2 through V2, Vj, C-l to Semi-Continuous
Stripping Still or Used Regenerant.
Steps 1, 2, 3 and 4 are repeated four more times in sequence as shown
above and respectively called steps (5, 6, 7, 8), (9, 10, 11, 12), (13, 14,
15, 16), (17, 18, 19, 20).
Step 21 Rinsing of Resin in Column 2—
?2 is still running V3 closes, V2 changes, V4 opens, Vs changes and H20
flows through V2, V4, C-2, V5 to Used Regenerant of Semi-Continuous Stripping
Still.
Step 22 Regeneration of Resin in C-2—
V2 changes, methanol is pumped by ?2 through V2, V4, C-2, Vs to Semi-
Continuous Stripping Still or Used Regenerant.
Automation 2
Steps of Automation of Bench Scale Unit for 2 columns of the same resin.
The following description of steps refers to Figure 4.
Step 1 Removal of Dyes and Additives in Dye Waste—
P! starts column 1 (C-l) dye waste by P.S.-l (safety pressure switch)
through V7, V-L, C-l, V3, C-2, V4, V5, V6 to effluent.
Step 2 Rinsing of Resin in (C-l)—
V7, V3, Vs, V6 change, Pump 1 (P-l) stops and P-2 starts H20 through
-------
V2> V7> vl> C'1- V3» V5» V6> to Semi-Continuous Stripping Still or Used
Regenerant.
Step 3 Regeneration of Resin in (C-l)—
Y£ changes, methanol is pumped by ?2 through V£, Vy, V-^, G-l, 73, V^, Vg
to Semi-Continuous Stripping Still or Used Regenerant.
Step 4 Rinsing of Resin in Column 1—
V£ changes and H20 is pumped by ?2 through V2, Vj, C-l, 73, V$, Vg to
Semi-Continuous Stripping Still or Used Regenerant.
Step 5 Removal of Dyes and Additives in Dye Waste Through Column 2 (C-2)—
Vjf V^, Vg change. Pump 2 stops and Pump 1 starts dye waste through
V?, Vi, C-2, V4, C-l, V3, V5, Vg to effluent.
Step 6 Rinsing of Resin in C-2—
Vy, V4, Vg, Vg changes. Pump 1 stops and Pump 2 starts H^O through V2»
V7, V]_, C-2, 74, V5, Vg to Semi-Continuous Stripping Still or Used Regenerant.
Step 7 Regeneration of Resin in C-2—
V2 changes and methanol is pumped by P2 through V2» Vy, V^, C-2, 74, Vg,
Vg to Semi-Continuous Stripping Still or Used Regenerant.
Step 8 Rinsing of Resin in C-2—
V2 changes and 1^0 is pumped by ?2 through V2, V7, Vj, C-2, V4, V5, Vg
to Semi-Continuous Stripping Still or Used Regenerant.
STILL FOR METHANOL RECOVERY
A semi-continuous column stripping still was set up to remove methanol
from the methanol dye regenerant. A five-liter round bottom three neck glass
jointed flask fitted with a Vigreux distilling column over an Oldershaw sieve
plate column composed the still, see Figure 5. Methanol regenerant and water
rinse mixture (Used Regenerant) was fed through a side adapter tube connected
between the two columns. The flask was heated with a heating mantle to 102-
105°C. Temperature was monitored with a thermometer placed in one of the
three neck glass joints of the flask. Pure methanol distilled over at its
boiling point of 64°C while the dark mixtures of dyes, additives and water
continued down the sieve plated column to the flask. The pure methanol was
collected in a five gallon glass bottle from which it was drawn and reused
as the regenerant for removing the absorbed dyes from the exchange resin
columns. The still was operated manually. The used regenerant was collected
and later distilled.
COLOR REMOVAL
Visual Photography
A Nikon F-2 Photomic camera with filters and a tripod was used to visual-
ly show the removal of color by the use of color photography. This was deemed
necessary to prove the actual removal of color from the colored dye wastes.
8
-------
As shown below, the use of a Bausch and Lamb's Spectronic-20 not only regis-
ters the remaining color, but also any white emulsified polyethylene registers
as color.
Spectfbriic-20, Readings for Color Removal
The wavelength in which each dye waste effluent is monitored is deter-
mined by scanning the influent over the visible region. However, the thin
white emulsified polyethylene also registers as absorbance at the wavelength
used to detect the dye color. The white thin turbidity is clearly not due to
the dyes in the influent. Treatment with sulfuric acid or sodium hydroxide
solution had no visible effect, when the pH was changed from 1 to 13. Most
of the problem was overcome by diluting the influent, one to ten with water,
and measuring the dilute solution at the desired wavelength on the Spectronic
20. This gave a good indication of the removal of color, but not as absolute
as the actual color photos shown herein. The percent of color removed from
the influent was calculated as follows:
% Color Removed = Abs. influent -abs. effluent x 100
Absorbance of influent
COD and BOD
Samples were taken usually every 10 bed volumes for COD and BOD determi-
nations. Samples were preserved by refrigeration.
The BOD values were determined by the dissolved oxygen Probe Method using
a YSI Model 54 ARC Dissolved Oxygen Meter and YSI 5720 self stirring bottle
probe. The manufacturer's instructions were followed in calibrating the
meter. The air calibration method was used and checked against the Saturated
Water Method. Repeated readings of saturated water gave 8.4 + 0.1 ppm using
both methods at 28°C after correcting for barometric pressure. The solubility
of oxygen in fresh water for calibration was taken from Table 281 page 480,
Standard Methods for Examination of Water and Waste Water, 1971.
Flow Rates
Flow rates for loading columns were usually 4 bv/hr. The most feasible
flow rate for regeneration was 2 bv/hr. This allowed maximum contact time
between resin and methanol at a practical operation rate. The flow rates
for all rinses were 2 bv/hr-
Regeneration
Regeneration of the adsorption resin was all downflow through the
columns because of difficulties in backflow operation. The major problem
in backflow regeneration was the occasional creation of voids in the column
that allowed the methanol to channel, resulting in a loss of efficiency for
dye color removal. The advantage of Backflow operation would allow the column
to clean up more rapidly with less methanol extraction, however, downflow re-
generation was deemed more practical in everyday operation of the pilot unit.
-------
SECTION V
DISCUSSION AND RESULTS
GENERAL
The main Dispersed dyes used by the textile mills mentioned in the report
are of the structures shown in Figure 6. Though these dyes are used for dye-
ing nylon hosiery, other Dispersed dyes used in dyeing polyester, acrylics,
and acetates are not that much different and would be expected to have the
same adsorption characteristics.
A recently published article^ deals with research conducted at the Waste-
water Research Center. The report is timely in that it describes deficiencies
in the removal of Disperse dyes by activated carbon, ozone and biological
treatment.
The Major Conclusions as stated were:
1. The organic constituents in dyeing wastewater are relatively biode-
gradable, and BOD and TOG can be effectively reduced by biological
treatment.
2. Color, in general, is not readily removed by biological waste treat-
ment, suggesting that dye molecules are not readily biodegradable.
3. BOD and TOC removal by physical-chemical treatment techniques, i.e.
coagulation, carbon adsorption and ozonation, is not very effective.
4. Disperse, vat and sulfur dyeing wastewaters can be readily decolor-
ized by coagulation with alum, but are not readily decolorized by
activated carbon.
5. Reactive, basic, acid and azoic dyeing wastewaters can be readily
decolorized by activated carbon.
6. Reactive dyes can be decolorized most effectively by ozone; Dispersed
dyes are decolorized least by ozone.
As previously planned for this study, and before finalizing on a set of
operating conditions to otbain data for calculating costs, numerous phone con-
versations were had with the engineers of Rhom and Haas Company and the Hanes
Company Legg's Division. This included a two day consultation visit with Rhom
and Haas in Philadelphia and several day visits with Hanes in Winston-Salem,
North Carolina. The purpose of these discussions was to interpret the experi-
mental data to date, and to finalize the operating conditions to provide data
10
-------
for determining a most practical process with minimum capital and operating
costs requirements for the removal of Disperse dyes from wastes in plant ho-
siery dyeing operations. These same capital and operating cost estimates
could be applied to other Disperse dyeing operations in the textile industry.
Most hosiery dyeing operations are made with Disperse dyes only. Some indus-
tries use a small percentage of acid dyes along with Disperse dyes when they
are dyeing certain types of panty hose.
From an engineering standpoint the use of two columns in series contain-
ing the most efficient adsoprtion resin regenerated by methanol in both col-
umns would reduce the capital and operating costs as well as simplify the
controls of the operation. This would also avoid the use of acid and ba-
sic regenerants (pollutants in their own right) in the process.
Hanes Disperse Dye Wastes
As shown in Figure 7, complete removal of all color was obtained after
120 bv were passed through both columns containing resin XAD-7 only. After
about 30 bv, a slight white milkiness was present in the effluent which was
probably the white emulsified polyethlene softener that was dispersed by the
surfactant system used in the original plant dye formula. Spectronic-20 read-
ings of color removal are reported in Table 1 and shown graphically in Figure
8. Also shown in Figure 9 and Table 1 is the removal of approximately 50% of
the COD. The BOD content removal was 54% at 60 bv.
The above conditions were used in the Flip-Flop arrangement which is as
follows: The dyes waste is passed through Column 1 and Column 2 in series as
usual, containing the same resin. When the 120 bv has passed through both
columns, the first column is relatively completely saturated (complete colora-
tion of first resin columm with dye color noticeably in its effluent).
At this stage only one-fifth of the second resin in series is colored in
the second column; the rest of it is white and yet capable of adsorbing more
dyes. The waste dye loading cycle is stopped, then, only the first colored
saturated column is desorbed completely by regeneration with two bv of metha-
nol and then washed with one bv of water. The dye loading cycle is started
and the Flip-Flop arrangement takes place in that the two columns are re-
versed in their order of receiving the dye waste. Thus, the original second
column now becomes the first to receive the dye waste and the original first
column that has just been regenerated becomes the back-up column. This Flip-
Flop sequence occurs after each 120 bv of dye waste are passed and regenera-
tion of the leading column. There was no degeneration or apparent lessening
of efficiency of color removal of the XAD-7 resin after five complete cy-
cles or regeneration. In our main work earlier we have already demonstrated
that XAD-7 resin could be regenerated at least 25 cycles and still continued
to be as efficient. This is shown below with Glen Raven's Disperse dyes which
are the same as Hanes. Using XAD-7 followed by A-7 gave fairly good color
and COD removal, but only up to when 20 bv was passed, and then the resin had
to be regenerated, Figure 10 and Table 2.
As the single resin in both columns, the use of XE-275 or Duolite A-7 in
either their weak base or salt form also failed to give as many satisfactory
11
-------
TABLE 1. HAKES DISPERSE DYE (2XAD-7 COLUMNS)
Effluent
Bed
Cycle Volume
1 5
10
20
30
40
50
60
70
80
90
100
2 10
20
30
40
50
60
70
80
(continued)
Color Absorbance
Wave- %
Influent Effluent length Removed
1.75 .019 360
.020
.060
.100
.130
.190
.230
.280
.300
.660
1.080
1.75 .020 360
.060
.100
.140
.180
.230
1.75 .290 360
.300
99.0
99.0
97.0
95.0
93.0
89.0
87.0
84.0
83.0
62.0
38.0
99.0
99.0
96.0
94.0
93.0
89.0
87.0
85.0
COD
Influent Effluent
8160 600
720
850
1760
2500
3500
5900
6570
7196
7380
7500
8160 580
600
835
1560
2300
3400
8160 5700
6450
%
Removed
93
91
90
78
69
57
27
19
11
8
8.1
93.0
92.0
90.0
81.0
72.0
58.0
30.0
20.0
12
-------
TABLE 1 (continued)
Effluent
Bed
Cycle Volume
90
100
3 10
20
30
40
50
60
70
80
90
100
4 10
20
30
40
50
60
70
(continued)
Color Absorbance
Wave- %
Influent Effluent length Removed Influent
.660
1.080
1.75 .023 360
.050
.090
.150
.180
.230
.290
.300
.660
1.080
1.75 .020 360
.070
.080
.160
.200
.240
.300
63.0
38.0
99.0 8160
97.0
95.0
92.0
90.0
87.0
83.0
83.0
62.0
38.0
99.0 8134
96.0
95.0
91.0
89.0
86.0
83.0
COD
Effluent
7200
7300
590
600
840
2530
3250
6080
6670
7300
7400
7530
800
856
1860
2600
3500
6000
6600
%
Removed
11.0
10.0
93.0
92.0
90.0
69.0
60.0
26.0
18.0
9.0
9.0
7.0
90.0
90.0
77.0
68.0
57.0
26.0
19.0
13
-------
TABLE 1 (continued)
Effluent
Bed
Cycle Volume
80
90
100
5 10
20
30
40
50
60
70
80
90
100
Color Absorbance
Wave- %
Influent Effluent length Removed
.310
.660
1.100
1.75 .020 360
.080
.090
.160
.210
.240
.310
.310
.660
1.100
82.0
62.0
37.0
99.0
96.0
95.0
91.0
88.0
86.0
82.0
82.0
62.0
37.0
COD
Influent Effluent
7100
7400
7600
8134 830
856
1893
2680
3570
6070
6673
7190
7480
7670
%
Removed
12.0
9.0
6.0
90.0
90.0
76.0
67.0
56.0
26.0
18.0
11.0
8.0
6.0
14
-------
TABLE 2. HANES DISPERSE DYE (XAD-7 FOLLOWED BY A-7 COLUMN)
Effluent
Color Absorbance
COD
Bed Wave- % %
Cycle Volume Influent Effluent length Removed Influent Effluent Removed
1 5.2 1.75
10.4
14.7
25.0
2 5.0 1.75
10.0
20.0
30.0
0
.06
.58
.38
.02
.07
.60
.38
360 100.0 8160
99.4
67.0
78.0
360 99.0 8160
98.0
85.0
78.0
3000
3600
4100
7200
2900
3600
3700
4100
63
55
50
12
64
55
54
50
bv of color removal as the neutral XAD-7 resin above. Only about 30 bv of the
dye waste could be passed before the effluent became noticeably colored.
Glen Raven Disperse Dye Wastes
The main thrust here was to evaluate the long lasting qualities and re-
tention of efficiency of dye removal after each regeneration for resins XAD-7
and A-7 in tandum. As many as 25 complete cycles of regeneration with metha-
nol still gave good color removal, Figure 11, (about 90% removal of color by
Spectronic data) and 50% BOD and COD removal, Figures 12, 13, 14 and Table 3.
In this series before each regeneration 25 to 30 bv were passed, while still
maintaining about 85% color removal. The main goal here was to find out how
long these resins could retain their efficiency after numerous regenerations
before being seriously overloaded. Note, in the field these resins are re-
ported to last several years of continuous use before they are replaced.**
15
-------
TABLE 3. GLEN RAVEN DISPERSE DYE WASTE (XAD-7 FOLLOWED BY A-7 COLUMN)
Effluent
Color (absorbance)
COD
BOD
Cycle 1000 ml Influent Effluent Removed Influent Effluent Removed Influent Effluent Removed
cuts
1 1
2
3
4
5
6
7
8
9
2 1
2
3
4
5
6
7
8
9
4 1
2
3
4
5
6
3.51* .85
.38
.42
.48
.50
.68
.25
.16
.23
2.90 .15
.14
.25
.26
.23
.22
.24
.24
.22
1.30 .21
.20
.20
.14
.13
.13
75
89
88
86
86
81
93
95
94
95
95
91
91
92
92
91
92
92
84
85
85
89
90
90
1049 861
900
815
961
715
930
961
976
1122
1434 898
837
1089
1154
1182
1170
1227
1142
1182
748 307
358
436
524
480
544
18
14
22
8
32
11
8
7
37
41
24
20
18
18
14
20
18
59
52
42
30
36
27
6400
2950
2750
2850
2300
3000
3850
3775
3200
6300 3075
3100
3600
3750
3725
3850
4182
4100
3275
4850 1575
1750
1750
2200
2500
2425
53
57
55
64
53
40
41
50
51
50
42
40
40
38
33
34
48
67
64
64
55
48
50
*Wavelength used was 480 namometers for Cycles 1 through 5.
(Continued)
-------
TABLE 3 (continued)
Effluent
Color (absorbance)
COD
BOD
Cycle 1000 ml Influent Effluent Removed
Cuts
Influent Effluent Removed Influent Effluent Removed
4
5
6
7
8
9
1
2
3
4
5
6
7
a
9
10
1
2
3
4
5
1.30 .12
.11
.10
1.30 .21
.20
.18
.16
.16
.18
.14
.14
.12
.11
1. 30 . 10
.11
.12
.11
.11
91
92
93
84
85
86
88
88
86
89
89
91
92
92
92
90
92
92
748 495
583
590
748 209
238
321
304
321
521
585
604
1235 1000
1113
1146
1121
1138
34
22
21
72
68
57
59
57
30
21
19.
19
10
7
9
8
4850 2150
1900
2175
4850 2350
2375
2400
2300
2925
,;
5700 2250
2475
2650
2775
3150
56
60
55
52
51
50
53
40
61
57
54
51
46
(Continued)
-------
TABLE 3 (continued)
00
Effluent
Cycle BV** Influent
7
9
11
5 3.80
4.50
4.60
25 3.80
4.50
4.60
5 3.80
4.50
4.60
30 3. 80
4.50
4.60
5 3.80
4.50
4.60
15 3. 80
4.50
4.60
— — — — _^ ^.^ ___*_______
Color (absorbance) COD
Wave % %
Effluent length* Removed Avg. Influent Effluent Removed
.95
1.00
1.50
.86
1.00
1.50
.75
.95
1.00
.85
1.00
1.50
.75
1.20
1.00
.85
i.io
1.20
640
520
480
640
520
480
640
520
480
640
520
480
640
520
480
640
520
480
75
78
67
78
78
67
80
79
78
78
78
67
80
73
78
78
76
74
1809 880 51
73
ti
1809 754 58
74
ii
1809 870 52
79
ii
1809 763 58
74
ii
1809 893 51
77
it
1809 631 65
76
ii
ppm
Influent
7500
it
it
7500
ii
ii
7500
ti
ii
7500
11
11
7500
11
it
7500
it
ti
BOD
ppm %
Effluent Removed
3250 57
3450 54
3620 52
3333 56
3333 56
4000 53
* Average of the three wavelength readings used for Cycles 7 through 25.
**Data was taken at number of BV (bed volumes) passed for remaining cycles.
(Continued)
-------
TABLE 3 (continued)
Effluent
Cycle BV** Influent
11
13
15
16
25 3.80
4.50
4.60
30 3.80
4.50
4.60
5 3.80
4.50
4.60
25 3.80
4.50
4.60
5 3. 80
4.50
4.60
25 3.80
4.50
4.60
5 1.50
2.80
3.00
Color (absorbance)
Wave %
Effluent length* Removed
.80
.95
1.20
.75
.90
1.00
.81
1.00
1.00
.86
1.00
.82
.96
1.20
.85
.80
1.00
1.20
.36
.52
.61
640
520
480
640
520
480
640
520
480
640
520
480
640
520
480
640
520
480
640
520
480
79
79
74
80
80
79
79
78
78
77
78
82
75
74
81
79
78
74
76
81
80
COD
Avg. Influent Effluent
1809 786
77
it
1809 750
79
ti
1809 830
78
11
1809 790
79
ii
1809 850
77
n
1809 750
77
n
1144 562
79
it
BOD
% ppm ppm
Removed Influent Effluent
57 7500 3450
it
ii
59 7500 3320
n
ti
54 7500 3500
n
n
56 7500 3550
n
n
53 7500 3400
ti
n
59 7500 3650
n
it
51 6300 2980
ii
it
%
Removed
57
56
53
53
55
51
53
(Continued)
-------
TABLE 3 (continued)
Effluent
Cycle BV**
16 25
18 5
25
20 5
25
22 5
25
^^BIK^BBA4IH^^^^H^^^^^^^^^M
Influent
1.50
2.80
3.00
1.50
2.80
3.00
1.50
2.80
3.00
1.50
2.80
3.00
1.50
2.80
3.00
1.50
2.80
3.00
1.50
2.80
3.00
' • " - - - - — -- L-
Color (absorbance) COD
Wave %
Effluent length* Removed Avg. Influent Effluent
.23
.45
.54
.35
.44
.49
.22
.38
.49
.21
.33
.40
.18
.30
.43
.19
.30
.44
.20
.35
.46
640
520
480
640
520
480
640
520
480
640
520
480
640
520
480
640
520
480
640
520
480
85 1144 528
84 81 "
82 "
77 1144 576
84 81 "
81
85 1144 542
86 85 "
84
86 1144 498
88
87
88 1144 445
89 88 "
86
87 1144 520
89 87 "
85
87 1144 561
88 87
85
. . — • "• "• • • "
BOD
% ppm ppm %
Removed Influent Effluent Removed
54 6300 2630 58
11
"
50 6300 2800 56
"
"
53 6300 2850 55
"
"
56 6300 3100 50
"
"
61 6300 3130 50
ii
55 6300 2820 55
it
51 6300 2816 55
"
it
(Continued
-------
TABLE 3 (continued)
Effluent Color (absorbance)
Wave %
Cycle BV** Influent Effluent length* Removed
24
25
5 1.50
2.80
3.00
25 1.50
2.80
3.00
5 1.50
2.80
3.00
25 1.50
2.80
3.00
.17
.31
.39
.18
.36
.45
.18
.36
.35
.16
.34
.38
640
520
480
640
520
480
640
520
480
640
520
480
89
89
87
88
88
85
88
87
88
89
88
COD
Avg. Influent Effluent
1144 443
88
tr
1144 540
87
ii
1144 500
88
ii
1144 489
88
ii
BOD
% ppm ppm %
Removed Influent Effluent Removed
61 6300 2910
ti
rt
60 6300 2856
n
it
56 6300 2910
n
ii
57 6300 2851
n
n
53
55
53
55
-------
Hanes Acid Dye Wastes
Recently some work was done with Hanes acid dye wastes. Previously, only
Dispersed dyes were encountered in hosiery dyeing operations. However, now,
up to about 30% of Acid dyes may be used in sequence dyeing along with Dis-
perse dyes at some hosiery plants. In this case, one column was used and the
resin was Duolite A-7. Excellent color removal is shown in Figure 15. Sev-
enty bv was passed through the columns and the column was then methanol re-
generated and water rinsed for the next cycle in the usual way. As shown
in Table 4, there was no reduction efficiency of color removal through three
regeneration cycles. Color removal was 80% after 70 bv was treated. The
COD removal went from 60% to 30%, the average being about 45% by the time 70
bv was passed. The BOD removal at 20 bv was 53%. A preliminary run using
one column containing XAD-7 resin was about one-half as effective as Duolite
A-7 in removing the color in the initial cycle and the work was discontinued.
Sellers Reactive Dye Wastes
As usual, the dye wastes samples were taken just prior to discharging
(at their most concentrated stage and not diluted with rinse waters). Sellers
has a conventional type of package dyeing operation. The conditions used were
with XAD-7 in one column followed by A-7 in the second column. A total of 30
bv of reactive dye wastes could be passed, as shown in Figure 16, with no vi-
sual loss in color removal. As shown in Figure 17 and Table 5, color removal
dropped only to 80% after a total of 30 bv was passed, while 40% BOD and 55%
COD were removed at 20 bv. Also it can be seen, with the limited time at
hand, at least three complete cycles could be run with no loss of resin effi-
ciency for color removal.
Comparison of Technical Efficiencies and Costs with Other Dye Removal Pro-
cesses
Since hosiery dyeing plants normally operate at a rate that produces
10,000 to 20,000 gals/day of Disperse dye wastes, it is difficult to compare
cost data with the other three competitive processes for treating soluble
wastes at the normal large volume of 1 million gals/day, see Appendices.
However, of three potentially competitive processes, ozonation appears to be
the only practical competitor to the polymer adsorption process. Carbon
treatment and hyperfiltration are considered impractical on the basis of tech-
nical diffculties of dealing with nonsoluble Disperse dyes making their pro-
cess removal steps difficult and thus more costly. For instance, in hyperfil-
tration the minute pores in the membrane have become clogged and rendered
inoperative. Carbon treatment has been reported to be efficient for removal
of soluble dyes but not effective for Disperse dyes.5 Also, with carbon
treatment regeneration of the adsorbent would be difficult and quite costly-
22
-------
TABLE 4. HANES ACID DYE (ONE A-7 COLUMN ONLY)
Effluent
Bed
Cycle Volume
1 10
20
30
40
50
60
70
2 10
20
30
40
50
60
70
3 10
20
30
40
50
60
70
Color Absorbance
Wave-
Influent Effluent length
1.00 .005 200nm
.009
.100
.107
.110
.156
.196
1.00 .006
.099
.100
.108
.110
.157
.199
1.00 .005
.099
.100
.107
.111
.158
.200
%
Removed
99.5
90.0
89.3
83.9
89.0
84.0
80.0
99.4
90.0
90.0
89.2
89.0
84.0
80.0
99.5
90.0
90.0
89.3
89.0
84.0
80.0
COD
Influent Effluent
5512 2016
2516
2935
3018
3118
3519
3916
5618 2173
2468
2955
3319
3346
3817
4056
5628 2185
2573
2948
3096
3220
3972
4176
%
Removed
63
54
46
45
43
36
30
61
56
47
40
40
32
27
61
54
47
44
42
29
26
23
-------
TABLE 5. SELLERS REACTIVE DYE WASTE
Effluent
Bed
Cycle Volume
1 5
10
15
30
2 5
10
15
30
3 5
10
15
30
Color Absorbance
Wave-
Influent Effluent length
4.80 .13 340
.17
.53
.99
4.80 .15 340
.18
.98
1.00
4.80 .16 340
.19
.73
.99
%
Removed
97
97
89
80
97
96
80
79
97
92
84
80
24
-------
Capital and Operating Costs—Adsorbent Resin Process
Hosiery Waste Plant Color Removal (20,000 gal/day, 2 shift)
A. Capital Cost (installed)
Equipment, tanks, pumps, columns, etc. $63,00,0
300 gal/day Simple Methanol Stripping Still 10,OdO
Engineering & Field Supervision 7,500
60 cu. ft. Adsorbent Resin (for 2 columns) 6,000
Total Capital $86,500
B. Operating Costs/Yr.
1,800 gal Methanol make-up at 98% recovery $ 900
Resin Amortization (5 yr. life) 1,200
Electricity and supplies 500
Repairs (3% of Equipment Capital $71,000) 2,130
Steam at $2/1000 Ibs. for 300 gal/day MeOH 700
Labor, 1/5 man per two shifts 4,000
Operating cost/year., total $ 9,430/yr.
At 300 day/year operation cost—
$/1000 gal =/9430 x 1000 gal/(20,000 gals x 300> = $1.57/1000 gals
Capital costs amortized as operating costs/1000 gals = $1.90
Total annualized operating costs = $3.47/1000 gals
Assumptions:
(1) Stripping of MeOH done during the two shifts, but automatic adsorp-
tion run around the clock.
(2) Savings realized by reuse and recycle of water and some surfactants
and polythethylene softener will balance off other miscellaneous
costs as taxes, etc.
(3) Concentrated oily dye methanol stripped waste will be dripped into
oil furnace and burned as fuel.
(4) Small amounts of acid dyes when used with Disperse dyes in some
plants would be handled by the same single resin such as XAD-7.
(5) Capital costs amortized over ten years at an annual interest rate
of 10%.
25
-------
Capital and Operating Costs—Ozonation Process
Hosiery Waste Plant Color Removal (20,000 gal/day, 2 shift)
A. Capital Costs
60#/day Ozone Plant (Air Feed) $25,000
Auxiliaries (Air driers, Compressors, pumps, etc.) 12,000
Piping and installation for ozone 10,000
Treatment contactor, tanks, controls, installation 8,000
Total Capital $55,000
B. Operating Costs/Yr.
800 KW hrs/day (Electricity 03 & Auxiliaries $ 7,200
at 3C/KW x 300 days
Cooling Water at 70°F at 0.8 g/min/#03 1,200
Repairs (3% of Capital Equipment) 1,650
Labor, 1/10 man per two shifts 2,000
Operating Costs/yr. total $12,050
Cost in $/1000 gals = 12,050 x 1000/20,000 x 300 = $2.00/1000 gals
Capital costs amortized as operating costs = $1.21
Total annualized operating costs = $3.21/1000 gals
Assumptions:
(1) The ozone dosage to reduce color to acceptable limits was estimated
to be 35 mg 03/liter of waste. This is a modest assumption in that
03 dosages run from 5.0 mg to 1000 mg/liter as shown in the ozone
cost studies in the appendix sections of this report.
(2) Capital cost amortized over ten years at an annual interest rate
of 10%.
A comparision of the two processes, 03 vs. Resin Adsorbent, shows that
the operating cost estimates are fairly close to each other and a demonstra-
tion plant for each on the same dye waste could decide which may be better.
At first appearances, the ozone approach is more simple and direct, but a
build-up of the decolorized ozidized dyes and surfactants by ozonation would
certainly occur. For instance, it is well known that Disperse dyes are sold
as mixture of the dye at about 40% and a dispersion agent as lignin sulfonate
60%. It is also known that lignin sulfonate is fairly readily attacked by
ozone. Thus, a portion of the effluent would have to be discarded to avoid
a build-up of organic compounds in the recycle system. On the other hand,
by the adsorbent process, as long as the colored dyes are removed, any addi-
tives such as surfactants, wetting and dispersion agents would be left un-
changed and usable. This would be an extra saving. Thus, in the make up for
each new dye formula only part of the additives would have to be added.
26
-------
Figure 1. The automatic bench scale pilot unit.
27
-------
HOY
a.c.
PI"?
p,»tv c.ev-4
GlroClbd to
P.S.-1
f>S:2
Figure 2. Pictorial wiring diagram.
28
-------
v£>
o
n JT
HOH
MeOH
O PS-2
Effluent
PS-lQ
Used
Regenerant
figure 3. Sketch of bench scale pilot unit, each column containing a different resin in series.
-------
MeOH Effluent
Used
Regenerant
Figure 4. Sketch of bench scale pilot unit, each column containing same adsorbent resin.
-------
thermometer
to methonol pump
for regeneration
methanol
distillate
removal of concentrate
feed from
methonol
regenerant
thermometer
dyes,
additives
and water
Figure 5. Semi-continuous stripping still.
31
-------
2~
H9CHnOH
TERASIL-SCARLET B
NaO
CHoCOHN
—N—N
CIBOCET YELLOW 2GC
NHCH.
NHCH2CH2OCH2CH2OH
CIBOCET BLUE BN
Figure 6. Main colors, Glen Raven disperse dyes.
32
-------
Influent
Effluent
Figure 7. Hanes disperse dye wast, color photo showing
complete removal of color after 120 BV, same
resin.
33
-------
1, 2, 3, 4, 5
(not different enough to distinguish separately)
30 40 50 60 70
Number of Bed Volumes
Figure 8. Hanes disperse dye waste, % color removal
vs. bed volumes treated.
34
-------
I 50
,3
Q «
O
O
e-s 40
35
30
25
20
15
10
5
Cycles: 1, 2, 3, 4 and 5
I
I
I
J_
0 10 20 30 40 50 60 70 80
Number of Bed Volumes
90
100
Figure 9. Hanes disperse dye waste, % COB removal
vs. bed volumes treated.
35
-------
a
70
60
50
40
§ 30
o
M 20
10
Cycles: 1 and 2
10 20
Number of Bed Volumes
30
100
95
90
£ 85
| 80
M
O
o
o
70
65
60
55
Cycles: 1 and 2
10 20
Number of Bed Volumes
30
Figure 10. Hanes disperse dye waste, % color and COD removal vs. bed
volumes treated (2 columns, XAD-7 and A.-T).
36
-------
Influent Effluent
Figure 11. Glen Raven disperse dye waste, color photo of color removal.
37
-------
95
oo
90
85
O
U
80
75
70
Cycles: 7, 9, 11, 16, 18 and 20
20
I
I
L
10 15 20
Number of Bed Volumes Treated
25
30
Figure 12. Glen Raven Disperse dye waste, % color removal vs. bed volumes treated.
-------
u>
V0
70
65
60
(U
1 55
50
45
Cycles: 11, 16, 18 and 20
18
20_
_L
10 15 20
Number of Bed Volumes Treated
25
30
Figure 13. Glen Raven Disperse dye waste,' % BOD removal vs. bed volume treated.
-------
I
** 55
Cycles: 11, 15, 16, 18 and 20
45
10 15 20
Number of Bed Volumes Treated
Figure 14. Glen Raven Disperse dye waste, % COD removal vs. bed volumes treated.
-------
Influent Effluent
Figure 15. Hanes acid dye waste, color photo of color removal.
41
-------
Si
u
70-
60
50
30
20
10
0
100
95
90
« 85
(S 80
M
I"
N 70
65
60
55
0
Cycles: 1, 2 and 3
10
30 40
i
20 30 40 50
Number of Bed Volumes
Cycles: 1, 2 and 3
JL
JL
10
20 30 40 50
Number of Bed Volumes
60
60
70
70
Figure 16. Hanes acid dye waste, % color & COD removal vs. bed volumes treated.
42
-------
Influent Effluent
Figure 17. Sellers reactive dye waste, color photo of color removal.
43
-------
100
90
80 .
O
O
70
60 -
Cycles: 1, 2 and 3
10 20
Number of Bed Volumes
30
Figure 18. Sellers reactive dye waste, % color
removal vs. bed volumes treated.
44
-------
SECTION VI
REFERENCES
1. Proposed Criteria for Water Quality, Vol. 1, Report No. EPA-R-3-73-003.
U. S. Environmental Protection Agency.
2. Standard Methods for the Examination of Water and Wastewater, American
Public Health Association, 13th Edition, New York, (1971).
3. Abstracts Workshop: Ozone/Chlorine Dioxide Oxidation Products of Or-
ganic Materials. 11/17-19/1976. Cincinnati, Ohio, by International
Ozone Institute & EPA.
4. Carcinogens in U. S. Drinking Waters, OZONews 1(3): 1-4, 1974, Inter-
national Ozone Institute.
5- Dye Study Focuses on Treatment, ESE Notes, Vol. 12, No. 2, School of
Public Health, University of North Carolina at Chapel Hill.
6. Process for the Recovery of Phenol from Aqueous Streams, Acetone Regener-
ation System, Rhom & Haas Co., Bulletin, 1976.
7. Survey of Textile Wastewater Treatment, State of the Art, Add-On Treat-
ment Processes — Prepared by Hydroscience, Inc., 363 Old Hook Road,
Westwood, New Jersey 07675, April 30, 1976.
45
-------
TABLE OZ-1
ESTIMATED CAPITAL COST FOR OZONATION OF WASTEWATER
Capital Cost to Add
Capital Cost to Add Approximately
Approximately 5 mg/1 1,000 mg/1 Ozone
Ozone (Disinfection) (Decolorization)
(x $1,000) (x $1,000)
Injector Mixers 10.2 10.2
Reactors and Holding Tanks 101.5 101.5
Oxygen Compressors 11.6 69.6
Dryers 16.0 43.5
Ozone Generators 36.3 1,196.0
Ozone Decomposer 1.5 1.5
Piping 49.3 49.3
Electrical 29.0 43.5
Instrumentation 30.5 30.5
Painting 7.3 11.6
Sitework 14.5 14.5
Equipment Supports & Bldg. 72.5 72.5
Total Materials & Labor $380.2 $1,644.2
Engineering, Contractor's ,,,.. n .
Oberhead, and Fee &J.14.1 ? 493.3
Total Capital Cost $494.3 $2,137.5
46
-------
RESIN/POLYMER ADSORPTION SYSTEM
OPERATING COSTS FOR 1 KGD PLANT
Labor at $15,000/man/year
Electricity at $0.02/KWH
Maintenance at 6% fixed capital
Steam at $2/1,000 pounds
Methanol at 97% recovery
dollars/year
$ 60,000
1,000
60,000
38,000
214,000
Polymer replacement at five-year life 42,000
Total
$415,000
or
$1.15/1,000 gallons
or
$0.009/pound carpet
COSTS BY SUBCATEGORY
Flow
(MGD)
Wool Scour
Wool Finish
Dry Process
Woven Fabric 2
Knit Fabric 2
Carpet Mills 1
Stock & Yarn 1
Capital
Operating/
1,000 gallons
1 $ 1,000,000
2 1,500,000
0,35 530,000
1,500,000
1,500,000
1,000,000
1,000,000
$1.91
0.98
1.43
0.43
0.43
1.15
0.62
Operating
pounds product
$0.014
0.014
0.002
0.009
0.009
0.009
0.014
Total
Anmutlized
Cost*
./I, OOP gal
2.35
1.21
2.11
0.76
0.76
1.59
1.06
*ten years at 10%j includes operating costs.
47
-------
TABLE CA-1
CARBON ADSORPTION SYSTEM COSTS (2.0 MILLION GALLONS/DAY SYSTEM)
Capital Cost _ _ 0 & M Cost _ _ Combined Cost
Sub-category
Wool Scouring
Wool Finishing
Woven Finishing
(Simple)
(Complex)
Knit Finishing
(Simple)
^ (Complex)
CD
Carpet Mills
(Simple)
(Complex)
$ 1,000
1,880
1,890
1,800
1,950
1,800
1,880
1,810
1,850
$/l,000 gallons*
.42
.42
".40
.43
.40
.42
.40
.41
$/year
318,408
327,712
258,312
370,736
253,190
316,360
266,600
293,056
$/l,000 gallons
.44
.45
.35
.51
.35
.43
.37
.40
$/year
624,408
635,712
551,312
624,736
564,190
622,360
561,600
694,056
5/1,000 gallons
0.86
0.87
0.75
0.94
0.75
0.85
0.77
0.81
Stock & Yarn 1/840 .41 284,264 .39 583,264 0.80
Dyeing & Finishing ' '
*Amortized over ten years at an annual interest rate of 10%.
-------
A typical 1 MGD plant may have the following costs; assuming
the concentrate can be reused or disposed. No costs for
handling the concentrate are included, mainly because there
is a lack of information on practicable methods of disposal
other than reuse in manufacturing processes. Costs for
pretreatment, which could include chemical coagulation,
filtration, and pH adjustment, are also not included.
Operating costs .50/1,000 gallons
Capital Costs (1 MGD rated capacity) $1,500,000
Annualized capital cost .67/1,000 gallons
Total cost, including amortization $1.17/1,000 gallons
49
-------
PROCESS SUMMARY SHEET
OZONATION
Effectiveness for
Treatment of Pollutant
Parameters
Powerful oxidant which is effective
in destroying organic contaminants.
Color, fecal coliforms, COD.
Textile Categories Applicable Polishing step to remove dyes which
are inert to conventional treatment.
Also may be used for disinfection.
State of Technological
Development
Process is well defined. Application
to wastewater treatment has only
recently become popular.
Application Data Availability:
1. Benefit to Effluent
2. Control capability
3. Dependability
Energy Considerations
Can achieve zero BOD and coliforms,
low suspended solids, high dissolved
oxygen, low color and COD.
Highly trained personnel would be
required to operate and maintain
equipment.
No concrete data.
Fairly low - 1 to 3 kwh/1,000 gallons
Total costs including capital $0.31/1,000 gallons for 5 mg/1
disinfection: $1.89/1,000 gallons for
1,000 mg/1 color, organic destruction.
Secondary/Environmenta1
Factors
Ozone is toxic at high concentrations
but is relatively unstable.
Other Considerations
Use of pure oxygen improves generation
efficiency but increases cost and
energy required. Some consideration
should be given to ozone in combination
with other AWT systems.
50
-------
PROCESS SUMMARY SHEET
RESIN/POLYMER ADSORPTION
Effectiveness for 90%-95% for color in waste
Treatment Pollutant 40% for BOD effluent
60% for COD streams
Parameters BOD, COD, and color
Textile Categories that Generally for all secondary
are applicable effluents
State of Technological Research and pilot stage.
Development Only one application on a
concentrated inplant dye waste
stream, apparently performing
well. Require pilot testing jbo
determine applicability and
design parameters.
Application Data Availability
1. Benefit to Effluent Not defined. May be useful for
color.
2. Control Capability Trained operators required to
operate regeneration system.
3. Dependability Not known.
Energy Considerations Substantial for solvent regeneration
system (4MM BTU/hour for a 1 MGD
plant). Incineration of organic
residue required.
Capital costs $1 million for 1 MGD plant
Operating costs Range 0.43 to 1.91/1,000 gallons
treatment.
Total annualized costs $0.76 to $2.35 per 1,000 gallons.
Secondary/Environmental Spent polymer and removed organics
factors ' • disposal may prove a problem.
51
-------
PROCESS SUMMARY SHEET
ACTIVATED CARBON ADSORPTION
GRANULAR BEDS
Effectiveness for
Treatment of Pollutant
Parameters
Activated carbon should be highly
effective for BOD, COD, and color.
While it may also reduce TSS, fecal
coliforms and oil and grease,
mechanical problems may preclude
its use as the technology of choice
for these parameters.
BOD, COD, color
Textile Categories Applicable All except dry processing, where
it does not appear necessary.
State of Technological
Development
Carbon adsorption is a well developed
technology which has been in use
for many years. New methods for the
regeneration of spent activated carbon
are still being developed and improved.
Application Data Availability:
1. Benefit to Effluent
2. Control capability
3. Dependability
Energy Considerations
Color removal has been demonstrated
in the textile industry. BOD and COD
removal have been demonstrated in
other industries.
Carbon adsorption is easily controlled.
Regeneration is more difficult.to
control.
Adsorption is highly dependable.
Regeneration requires a high level of
skill to operate, and may be less
dependable.
Carbon adsorption requires very little
energy relative to biological treatment,
Carbon regeneration is highly energy
consumptive.
Total costs including capital $0.75-0,94/1,000 gallons
Secondary/Environmental
Factors
Other Considerations
If carbon is regenerated thermally,
controls will be necessary to prevent
the discharge of air pollutants.
More than half of the cost, and
almost all of the energy requirements
of activated carbon systems are
associated with the regeneration of
spent carbon. If a more effective
means of carbon regeneration were
developed, the use of activated
carbon would be considerably more
attractive.
52
-------
PROCESS SUMMARY SHEET
REVERSE OSMOSIS
Effectiveness for
Treatment of Pollutant
Parameters
Excellent; product stream will
contain zero suspended solids and
fecal coliforms, low BOD, COD.
Soluble BOD, COD
Textile Categories Applicable All, with pretreatment of secondary
effluent.
State of Technological
Dev e1opment
Numerous reverse osmosis installations
on water supply. Process development
continuing in area of membranes and
suitability to wastewater treatment.
Main applications in area of wastewater
renovation-and reuse with recovery of
removed materials.
Application Data Availability;
1. Benefit to Effluent
2. Control capability
3. Dependability
Product water should generally be
reusable.
Equipment easily controlled.
Possible problems with membrane
fouling, and membrane life. Modular
construction facilitates maintenance.
Relatively low - pumping to high
300-500 psi pressure only required,
however, hadnling of concentrated
brine may require use of high energy
process.
Total costs including capital Variable depending upon design and
salinity. Range is $.80 to $2.00 plus/
1,000 gallons.
Energy Considerations
Secondary/Environmental
Factors
None
Other Considerations
Handling of brine (10% to 30%) of
inflow an important factor in
feasibility of process. May require
costly evaporation distillation/
incineration processes- Pretreatment
for removal of suspended solids, pH
adjustment, and biological growth
control is required.
53
-------
GLOSSARY
acid dye: a dye which has anionic groups which dissociate to give negatively
charged coloured ions and applied from an acid dyebath to dye fibers that
have basic groups (polyamides, wool, silk, etc.)
Amberlite XAD-7: a synthetic macroreticular polymeric exchange resin of sty-
rene-divinyl benzene with methacrylic ester groups. Amberlite is the
designation for Rhom & Haas Co., Philadelphia, Pennsylvania.
Amberlite XE-275: a weak base anion exchange resin.
biodegradable: the type of substance that can be broken down by microorganisms.
BOD: the amount of dissolved oxygen consumed in five days by biological pro-
cesses breaking down organic matter in an effluent.
chelate: to form an heterocyclic ring compound which contains the heterocy-
clic metal in the ring.
COD: a measure of the amount of oxygen required to oxidize organic and oxidiz-
able inorganic compounds in water.
disperse dyes: a class of substantially water-insoluble dyes applied from fine
aqueous suspensions for dyeing hydrophobic man-made fibers (nylon, poly-
ester, etc.)
Duolite A-7: an aminated phenol-formaldehyde condensate polymeric weak base
anion exchange resin of Diamond Shamrock Co., Redwood City, California.
hyperfiltration: a synonym for Reverse Osmosis. A process used in the general
sense of leaving behind large molecules or ions that are dissolved in a
wastewater which is forced under pressure through a fine porous membrane.
Relatively pure water is forced through leaving behind a concentrated
solution containing the molecules or ions.
reactive dye: a dye, which under suitable conditions, is capable of reacting
chemically with a fiber to form a covalent dye-fiber linkage.
54
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/2-77-136
3. RECIPIENT'S ACCESSION-NO.
4. TITLE AND SUBTITLE
Automatic Exchange Resin Pilot Plant for Removal of
Textile Dye Wastes
5. REPORT DATE
July 1977
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Allison Maggiolo and J. Henry Sayles
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Bennett College
Greensboro, North Carolina 27420
10. PROGRAM ELEMENT NO.
1BB610
11. CONTRACT/GRANT NO.
Grant R803455-01
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Grant Final: 4/75-4/77
14. SPONSORING AGENCY CODE
EPA/600/13
15.SUPPLEMENTARY NOTES T.ERL-RTP project officer for this report is Max Samfield, Mail
Drop 62, 919/541-2547.
16. ABSTRACT The report gjves results of SLR investigation of the use of adsorption resins
to remove colored dyes from textile dyeing wastewaters, using an automated bench-
scale pilot unit. This could make possible the reuse of the treated wastewatefs in sub-
sequent dyeing operations. The scale of operation facilitated accumulation of reliable
data on which to base cost estimates for commercial operation. At a wastewater
treatment rate of 20,000 gpd by resin adsorption, the amortized operating cost is
estimated to be $3.47/1000 gal. An estimated capital investment of $86,000 will be
required. These costs are believed competitive to other possible dye waste treatment
processes. Use of properly selected adsorption resins was found to be effective for
removing dyes from textile wastewaters. The finding is particularly important to the
use of dispersed type dyes, which are largely inert to biological waste treatment pro-
cesses , passing through such treatment relatively unchanged. In addition to the pos-
sible reuse of treated wastewater and elimination of possible damage to natural aes-
thetics , the removal of color substances reduces the tendency toward several other
ecological problems in effluent receiving waters. Color substances tend to reduce
light penetration and subsequent production of oxygen by photosynthesis, damaging
marine life and algae growth. They also chelate metal ions, and some are toxic and
suspect carp.inngens _ __
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
cos AT I Field/Group
Pollution
Textile Industry
Decoloring
Dyeing
Waste Water
Circulation
Water Treatment
Adsorption
Polymers
Pollution Control
Resin Adsorption
13B
HE
13H
07D
13. DISTRIBUTION STATEMENT
Unlimited
19. SECURITY CLASS (ThisReport)'
Unclassified
21. NO. OF PAGES
63
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
55
------- |