CHROIV1ATE RECOVERY FRJOIVi CHRQMATING RINSEWATER
IN THE METAL-FINISHING INDUSTRY
by
Arun R. Gavaskar, Robert Fj. Olfenbuttel, and Eric H. Drescher
Battelle
Columbus, Ohio 43201
Contract No. 68-CO-0003
Work Assignment No. 3-36
Project Officer
Lisa Brown
Waste Minimization, Destruction, and Disposal Research Division
Risk Reduction Engineering Laboratory
Cincinnati, Ohio 45268
NATIONAL RISK MANAGEMENT RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
\Printed on Recycled Paper
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NOTICE
This material has been funded wholly or in part by the U.S. Environmental Protection
Agency (EPA) under Contract No. 68-CO-0003 to Battelle. It has been subjected to the Agency's
peer and administrative review and approved
'or publication as an EPA document. Approval does
Protection Agency or Battelle; nor does menti
not signify that the contents necessarily reflect the views and policies of the U.S. Environmental
of trade names or commercial products constitute
endorsement or recommendation for use. This document is intended as advisory guidance only to
jrc
the metal-finishing industry in developing app
caches to pollution prevention. Compliance with
environmental and occupational safety and health laws is the responsibility of each individual
business and is not the focus of this documert.
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FOREWORD
The U.S. Environmental Protection Age icy is charged by Congress with protecting the Nation's
land, air, and water resources. Under a mandate )f national environmental laws, the Agency strives to
formulate and implement actions leading to a compatible balance between human activities and the ability
of natural systems to support and nurture life. To meet these mandates, EPA's research program is
providing data and technical support for solving environmental problems today and building a science
knowledge base necessary to manage our ecolog cal resources wisely, understand how pollutants affect
our health, and prevent or reduce environmental r sks in the future.
The National Risk Management Research Laboratory is the Agency's center for investigation of
technological and management approaches for reducing risks from threats to human health and the
environment. The focus of the Laboratory's resea ch program is on methods for the prevention and control
of pollution to air, land, water and subsurface reso jrces; protection of water quality in public water systems ;
remediation of contaminated sites and groundwater; and prevention and control of indoor air pollution. The
goal of this research effort is to catalyze development and implementation of innovative, cost-effective
environmental technologies; develop scientific and, engineering information needed by EPA to support
regulatory and policy decisions; and provide technical support and information transfer to ensure effective
implementation of environmental regulations and strategies.
This publication has been produced as part of the Laboratory's strategic long-term research plan.
It is published and made available by EPA's Office
of Research and Development to assist the user
community and to link researchers with their clients.
E. Timothy Oppelt, Director
National Risk Management Research Laboratory
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ABSTRACT
The recovery system evaluated in this study combines various aspects of vacuum
evaporation and flash distillation. It provides a
continuous supply of good quality rinsewater to the
chromating line at QRD. Recirculation prevents! nearly 450,000 gal of water from going to waste
every year. Contaminants removed from the circulating water include chromium, zinc, and other
dissolved solids. Contaminants are concentrated in a smaller wastestream (approximately
200 gal/yr) and disposed. Because QRD uses three different chromate formulations on a single
chromating line, this concentrate could not be reused. At plants that use a single formulation,
reuse may be possible, provided that the levels of zinc and iron do not increase to a point where
they affect the chromating quality. Because wastewater (requiring treatment) is not generated, the
recovery system leads to a reduction in wastewater treatment costs. Overall operating cost
reduction depends on the individual user's expected wastewater treatment costs. At QRD, the
return on investment was sufficient for the initi
4 years.
capital outlay to be recovered in approximately
This report was submitted in partial ft Ifillment of Contract No. 68-CO-0003, Work
Assignment 3-36, under the sponsorship of the
covers a period from May 1, 1992 to January C
January 31, 1994.
U.S. Environmental Protection Agency. This report
1, 1994, and work was completed as of
IV
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CONTENTS
Notice jj
Foreword jjj
Abstract jv
Figures . . . vj
Tables vj
Acknowledgments vii
SECTION 1: Project Description 1
Project Objectives I. 1
Description of the Site and the Technology to Be Studied 2
Summary of Approach 5
Product Quality Evaluation 5
Pollution Prevention Evaluation . . 5
Economic Evaluation 6
SECTION 2: Product Quality Evaluation ... 7
On-Site Testing 7
Analytical Testing Results 7
Product Quality Assessment 10
SECTION 3: Pollution Prevention Potential 14
Waste Volume Reduction I 14
Pollutant Reduction [ 14
Pollution Prevention Assessment 15
SECTION 4: Economic Evaluation , * 17
Major Operating Costs 17
Capital Cost 19
Economic Assessment t 19
SECTION 5: Quality Assurance 20
On-Site Testing 20
Laboratory Analysis 21
Limitations and Qualifications 22
SECTION 6: Conclusions and Discussion . . 23
SECTION 7: Reference 24
APPENDIX A: Manufacturer's Description of the Vacuum Evaporation/Flash Distillation
System (. 25
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CpNTENTS
(Continued)
APPENDIX B: Wastewater Treatment Plant 0
Rolling & Deburring Co
APPENDIX C: Analysis of Samples Collected
aerating Costs at Quality
29
rorn the Sump Tank 30
APPENDIX D: Manufacturer's Description of Other Potential Applications for the Vacuum
Evaporation/Flash Distillation System . . I 31
Number
1
2
3
FIGURES
Page
i
Chromating rinsewater recovery sys'tem 3
Daily trends for chromium in Rinse \ Tank, Rinse 2 Tank, and processed water ... 11
Daily trends for total dissolved solid's in Rinse 1 Tank, Rinse 2 Tank, and
processed water I , 12
Chromium in the inlet and outlet waters 16
TABLES
1 Water quality in rinse tanks ! 8
2 Processed water quality I . . 8
3 Characterization of distillation still bottoms and chromate. tanks 10
4 Major operation costs comparison i 18
5 Precision of analysis I 21
6 Accuracy of analysis 22
vi
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ACKNO
WLEDGMENTS
The U.S. Environmental Protection Agency and Battelle wish to thank Sumner Kaufman,
Connecticut Hazardous Waste Management Service, for his important support in locating the
technology and the test site. Mr. Kaufman prqvided continued assistance throughout the project.
We also wish to acknowledge Jim Schroeder ojf Quality Rolling & Deburring Co., who provided the
site and the recovery system for this test and made available all the site-specific information
required for the evaluation.
VII
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SECTION 1
PROJEC
DESCRIPTION
The goal of the U.S. Environmental Protection Agency's (EPA) 33/50 Program (U.S. EPA,
1992) is to promote voluntary reductions in the release of targeted hazardous chemicals by 33%
by the end of 1992, and 50% by 1995. One objective of the 33/50 Program is to evaluate, in a
typical workplace environment, examples of prototype technologies that have potential for reducing
wastes at the source or for pollution prevention. The 33/50 Program is supported in Connecticut
by the Connecticut Hazardous Waste Management Service (CHWMS). In general, for each technol-
ogy to be evaluated, three issues should be addressed.
First, it must be determined whether the technology is effective in providing a satisfactory
product. Because pollution prevention or waste reduction technologies usually involve recycling or
reusing materials, or using substitute materials or techniques, it is important to verify that the
quality of the materials and the quality of the work product are satisfactory for the intended pur-
pose. Second, it must be demonstrated that using the technology has a measurable positive effect
on reducing waste or on preventing pollution. Third, the economics of the new technology must be
quantified and compared with the economics of the existing technology. It should be clear, how-
ever, that improved economics is not the only criterion for the use of the prototype technology.
There may be justifications other than saving money that would encourage adoption of new oper-
ating approaches. Nonetheless, information about the economic implications of any such potential
change is useful.
PROJECT OBJECTIVES
The goal of this study was to evaluate a system for removing chromate out of chromating
rinsewaters so that the rinsewater and the chomate could be reused. Chromium is on the EPA's
list of target chemicals for early reduction. This study had the following critical objectives:
« Evaluating the rinsewater quality to ensure its suitability for rinsing, as
well as evaluating the recovered
suitable for reuse.
chromate solution to ensure that it is
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Evaluating the pollution prevention potential of this technology.
Evaluating the economics of incorporating the system into the plant.
DESCRIPTION OF THE SITE AND THE TECHNOLOGY TO BE STUDIED
The site for testing this new technology was Quality Rolling & Deburring (QRD) Company
located in Thomaston, Connecticut. QRD emp
oys about 75 people, and for the past 40 years has
provided metals finishing services to manufacturers of metal parts such as rivets, eyelets, metal
stampings, and electronic components. Because many manufacturers no longer perform in-house
metal finishing, the volume of work at QRD has tripled in the last 3 years. Recently, QRD added a
chromating line to their plant. Machined parts jmade from a variety of metals are first subjected to
zinc electroplating or mechanical zinc plating and then given a chromate conversion coating to
improve corrosion resistance. This chemical treatment converts the metal surface to a superficial
layer containing a complex mixture of chromium compounds. One of three different chromating
formulations is used on the same line at QRD -- blue-bright, yellow iridescent, or clear-bright.
Since May of 1992, QRD has been operating their chromating line with a CAST™*
(Controlled Atmosphere Separation Technology)) chemical recovery system manufactured by Cellini
Purification Systems, Inc.* This recovery system uses various aspects of flash distillation and
vacuum evaporation technologies in conjunction with a patented liquid/vapor separation system to
recover the chromate from the rinsewater (see
system). The rinsewater is then reused.
Figure 1 shows the system as it is co
continuous process, operating 6 to 8 hours per
system come from zinc electroplating baths or
Appendix A for manufacturer's description of
nfigured at QRD. The chromating line at QRD is a
day. The metal parts (workload) entering the
mechanical zinc plating. Because QRD operates the
chromating line for a variety of clients with differing needs, they use three different chemical
formulations (shown as blue, yellow, and clear)
are not very high (generally around 1000 ppm)
. Chromate concentrations in these formulations
The parts are chromated with one of the
formulations before proceeding to the first rinse. The overspray collected from the chromating step
is recirculated back to the original chromate tanks.
The first rinse (Rinse 1) is essentially equivalent to a dragout tank which removes most of
the excess chromating solution. The oversprayj from the first rinse is returned to the Rinse 1 Tank.
The second (cleaner) rinse (Rinse 2) assures that the part is free from residue. The overspray
Mention of trade names or commercial products does not constitute endorsement or recommendation for use.
2
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from the second rinse is returned back to the
Rinse 2 Tank. Water from the Rinse 2 Tank is
manually transferred into the Rinse 1 Tank frc m time to time to maintain a countercurrent effect.
When a change is made between formulations (blue to yellow, etc.), the chromating line
is first purged with clean water to clear any residue of the previous formulation from the pipes.
This purge water is collected and sent to the sump tank.
The contents of the Rinse 1 Tank arje sent to the chromate recovery unit in small frequent
batches at an average of around 60 gal/hr. Irj the still of the recovery unit, the mixture is
continuously processed by the following methpd. The solution exits through the bottom of the still,
is pressurized, is sent through a low-temperatlire heat exchanger, and is returned to the still via a
proprietary spray nozzle design. The solution
in the heated solution vaporizes. The vapor is
falls with a downward velocity while water contained
drawn upward, passing through a water-cooled
condenser and finally returning to the Rinse 2|Tank. Approximately 30 gal of concentrate is
retained in the recovery still bottoms at most times. This bottoms material gets more and more
concentrated with time and is evacuated into the sump tank every 3 or 4 weeks, depending on
measurements of chromium and dissolved solids (conductivity) buildup.
At the end of each day's shift, the chromating line is shut down. All the water from the
Rinse 2 Tank is transferred to the Rinse 1 Tank. The recovery unit continues to operate throughout
the night (24-hr operation) processing water from the Rinse 1 Tank into the Rinse 2 Tank. This
nighttime operation allows the water in the rirse tanks to get some additional cleaning after
contaminant contribution from the chromating
line stops.
Because three different formulations (blue, yellow, and clear) are used on the same
chromating line, the resulting still bottoms concentrate contains a mixture of these formulations
and cannot be returned to any of the chromating tanks. Therefore QRD presently is not reusing the
recovered chromating solution. At plants where only one formulation is used or recycled at a time,
the chromating solution could potentially be reused. Ideally the bottoms material would be
evacuated at or after the time that its chromate concentration exceeds that in the chromate tanks.
In practice however, QRD has not let the bottoms concentrate to that extent but have evacuated
them periodically into the sump tank. When tne sump tank is full, QRD is able to concentrate the
contents of the sump tank down to about 200 gal that can be shipped out as hazardous waste. In
plants where the chromate concentrate from the still bottoms can be reused in the chromating
process, all the chromium may be eliminated from the wastestream.
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SUMMARY OF APPROACH
Testing was restricted to blue chromate, which is the most frequently used at QRD.
Because the chromate recovery' system functions 24 hr per day, it is always in steady state. The
!
chromating line operation also does not vary much from day to day. Figure 1 shows with asterisks
the points where samples were collected on the test day.
Product Quality Evaluation
The product quality testing in this project had two objectives. One was to show that the
water processed through the system is of good enough quality to be reused as rinse. The other
was to show that there is potential for reuse qf the still bottoms from the processing unit in the
chromating tanks under certain conditions.
To evaluate the rinsewater quality, gYab samples of the rinsewater from Rinse 1 Tank and
Rinse 2 Tank and the processed water from tre recovery unit (before it reaches the tank) were col-
lected and analyzed. The chromium level was
determine how much zinc is carried in from th
the main concern, but zinc also was analyzed to
5 previous process. Other general water quality
parameters also were analyzed. Tap water frDm QRD was sampled and analyzed. To determine
acceptability of the returned rinsewater, the p 'ocessed water was compared to the tap water. The
tap water also served as a field blank. These samples were taken throughout the test day
(Thursday) to account for any variability in the process. At the end of the daily shift, the chromate
recovery system continued to process the water, recirculating it from the Rinse 1 Tank to the
Rinse 2 Tank. The next morning (Friday), the
processed water in the two rinse tanks was sampled
again.
Periodically the still bottoms from the recovery unit were sampled and analyzed. This
was done to confirm the capability of the unit
still bottoms.
Pollution Prevention Evaluation
The pollution prevention potential of
chromating solution for potential reuse of the
and to verify the accumulation of chromium in the
this system is based on the successful recovery of
•insewater and the chromating solution. The
quantitative analysis determined how much water and chromium can be prevented from being
discharged.
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Economic Evaluation
The economic evaluation took into account the capital, operating, and waste treatment/
disposal costs. Capital costs include the costiof the chromium recovery unit and its installation.
The costs of operating with and without the recovery unit were compared. Operating costs include
the cost of water, energy (electricity, steam), .labor {operating time and waste disposal), and waste-
water treatment.
Waste treatment/disposal costs prio • to installing the recovery system were estimated
from the previous year's plant records. The objective of this economic estimation is to determine a
payback period for the purchase of the equipment.
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SECTION 2
PRODUCT QUALITY EVALUATION
The product quality testing involved sampling of the rinsewater at various points in the
process over one full shift to ensure that contaminant concentrations in the rinsewater remain at
low levels at all times and there is a correspon ling buildup of contaminants in the still bottoms of
the recovery unit. Figure 1 (in Section 1) shows the locations of the samples.
ON-S1TE TESTING
On-site testing was carried out over one shift by operating the chromating line
continuously from 9:30 am to 3:30 pm, excepj for a brief Va-hr break at 1:00 pm. Periodic water
samples were collected from both rinse tanks and from the processed water line. The processed
water sample represents the instantaneous quality of the water coming out of the recovery system
before it has a chance to combine with the water in the Rinse 2 Tank.
To observe the accumulation of chromate in the still bottoms, samples of the still bottoms
material were collected at the beginning, middle, and end of the shift. As a comparison, samples
of solution in the three chromate tanks also were collected.
For approximately 8 hours after the shift ended, the recovery system continued to
process the water from the Rinse 1 Tank into the Rinse 2 Tank. The next morning, at 8:00 am,
both rinse tanks were sampled again to observe the improvement in water quality. Another sample
All samples were shipped by overnight mail to the
of the still bottoms was collected at that time.'
analytical laboratory (Zande Environmental Sen
'ices, Inc., in Columbus, Ohio).
ANALYTICAL TESTING RESULTS
Tables 1 and 2 show the results of the analysis of the water samples. The Rinse 1 Tank
samples (W-R1-1 to W-R1-6) represent the quelity of the water recirculating in the first rinse sprays
on the chromating line. As the shift progresses, the quality of the water in this tank deteriorates as
7
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TABLE 1. WATER QUALITY IN RINSE TANKS
Sample No.
' Rinse 1 Tank
W-R1-1
W-R1-2
W-R1-3
W-R1-4
' W-R1-5
W-R1-6
Rinse 2 Tank
W-R2-1
W-R2-2
W-R2-3
. W-R2-4
; W-R2-5
W-R2-6
: (a) Next day.
; Sample No.
' W-PW-1
; W-PW-2
: W-PW-3
W-PW-4
W-PW-5
• W-TW-1 (a)
Time
9:30 a.m.
11:00 a.m.
12:30 p.m.
2:00 p.m.
3:30 p.m.
8:00 a.m.(a>
9:30 a.m.
11:00 a.m.
12:30 p.m.
2:00 p.m.
3:30 p.m.
8:00 a.m.(al
Cr
mg/L
2.57
12.0
29.5
14.6
24.7
8.91
0.21
O.435
0.589
0.843
1.35
0.593
TABLE 2. PROC
Time
9:30 a.m.
11:00 a.m.
12:30 p.m.
2:00 p.m.
3:30 p.m.
12:30 p.m.
(a) Field blank consisting of
;
Cr
mg/L
O.235
0.348
0.437
0.445
0.482
0.079
tap water sup
Zn
mg/L
4.50
23.5
61.0
32.5
53.2
26.1
0.442
1.15
1.50
3.28
3.97
2.42
TDS
mg/L
48
162
372
273
374
196
220
174
141
119
88
28
Cond.
//mhos/cm
60
200
475
340
450
312
280
190
180
160
130
55
PH
4.39
4.20
4.08
4.30
4.14
4.46
6.47
7.11
6.85
5.22
4.56
3.90
ESSED WATER QUALITY
Zn
mg/L
0.338
0.592
0.793
0.796
0.870
0.291
Dly at QRD.
8
TDS
mg/L
30
32
42
31
9
250
Cond.
//mhos/cm
55
60
80
80
80
400
PH
3.88
3.76
3.63
3.68
3.71
6.39
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shown by the increasing levels of the chromium, zinc, and total dissolved solids. This deterioration
can be monitored on site at the plant by measuring the conductivity. The pH fluctuates in a narrow
range but remains acidic due to the contribution from the chromating solution dragout. Chromium
levels in the Rinse 1 Tank increased to nearly 30 ppm during the shift. The contamination levels
are still acceptable for the first rinse, but Rinse 2 requires cleaner water.
The Rinse 2 Tank started the day wi :h about 50 gal of fresh tap water in it. This fresh
water is added daily to this tank to make up fcr losses in the system. The Rinse 2 Tank is
replenished throughout the shift with the processed water from the recovery unit. Contaminant
levels are thus held down to very low levels throughout the day in this tank (samples W-R2-1 to
W-R2-6). On the test day, chromium levels did not exceed 1.5 ppm in the Rinse 2 Tank. At the
end of the shift, all the water in the Rinse 2 Tank is transferred to the Rinse 1 Tank, from which it
is processed overnight through the recovery unit back into the Rinse 2 Tank. Sample W-R2-6
er
represents the water quality next morning afte
begins. This cleaned water is transferred frorr
almost empty by now), and fresh makeup (tap
goes down further. Sample W-R2-1 is a morn
the night's processing and before the next shift
the Rinse 2 Tank to the Rinse 1 Tank (which is
water is added to the Rinse 2 Tank and the cycle
continues. When fresh makeup water is added to Rinse 2 tank in the morning, the chromium level
ng sample after adding makeup water following
overnight processing.
The processed water (PW) quality samples immediately after the recovery unit are shown
in Table 2 (samples W-PW-1 to W-PW-5). A tap water blank was also collected at QRD and
analyzed as a comparison (W-TW-1). Conside
dissolved solids) can be seen in the processed
•able removal of contaminants (chromium, zinc, and
water compared to levels in the Rinse 1 Tank.
Chromium and zinc levels in the processed water were higher than in the tap water supply. The
chromium level in the processed water stayed
concentrations remained in a narrow range, although an upward trend is noted as the day
progresses. This may be due to the increasing
help to reverse this trend. Plants that operate
not have the benefit of overnight processing.
contaminant concentrations in the processed water until an equilibrium state is reached.
QRD has high dissolved solids levels
below 0.5 ppm on the test day. Chromium and zinc
deterioration of the Rinse 1 water feed to the
recovery system. Continued overnight processing and the daily addition of fresh makeup water
their chromating line all three shifts per day would
Such plants would see an upward trend in
in its water supply. The recovery unit reduces
dissolved solids in the rinsewater to levels below those in the tap water. The pH of the processed
water was consistently low, indicating some carryover of the chromating solution's acidic
components into the distillate. The low pH of
eventual lowering of the pH in the Rinse 2 Tar
the processed water (Table 2) contributes to the
k water (Table 1).
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The contaminants removed from the rinsewater accumulate in the still bottoms material
as seen in Table 3. Overnight processing of the rinsewater increases the accumulation. On the
morning after the test day, chromium concentrations in the still bottoms had risen to 224 ppm. A
sample taken from the blue chromate tank showed a concentration of 1,254 ppm. If blue were the
only formulation used on the line, the still bottoms would need a sixfold concentration to be
reusable in the chromate tank. Long before the concentration in the still bottoms reaches this
level, it is evacuated in the sump tank to maintain better quality in the rinsewater and also because
a very concentrated solution becomes too viscous for the recovery system pump to handle. When
the sump tank is full, its contents can be further concentrated to the required level. Fresh
chromate formulation can be added to make dp any shortfall. Plants that reuse the chromate
concentrate would have to carefully monitor levels of dissolved solids to ensure that contaminants
such as zinc and iron do not cause the chromating quality to deteriorate.
PRODUCT QUALITY ASSESSMENT
Daily trends for chromium and total dissolved solids (TDS) in the Rinse 1 Tank (dragout),
Rinse 2 Tank (final clean rinse), and in the processed water are shown in Figures 2 and 3. The
levels of these contaminants are prevented frtjm rising in the Rinse 2 Tank by the influx of
processed water from the recovery unit. Overnight processing while the chromating line is stopped
TABLE 3. CHARACTERIZATION OF DISTILLATION STILL BOTTOMS AND CHROMATE TANKS
Sample No.
Still Bottoms
C-SB-1
C-SB-2
C-SB-3
C-SB-4
Chromate Tanks
Blue (C-BCT)
Yellow (C-YCT)
Clear (CC-CCT)
Time
9:30 a.m.
12:30 p.m.
3:30 p.m.
8:00 a.m.(a)
2:00 p.m.
2:00 p.m.
2:00 p.m.
Cr
mg/L
162
168
216
224
1,254
1,471
3,860
Zn
mg/L
258
277
385
420
1,739
15
0.743
TDS
mg/L
2,280
2,240
3,170
3,610
1 6,740
3,590
25,110
Cond.
^/mhos/cm
2,700
2,500
3,200
4,000
12,000
15,000
28,OOO
PH
3.52
3.59
3.80
3.95
2.57
1.55
2.87
(a) Next day.
10
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O)
E.
c
o
'•s
i=
CD
O
O
O
a
o
9:30 AM 11:00 AM
12:30PM 2:00 PM
Time of Day
I ] Rinse 1 -f~ Rinse 2 \/ Process Water
3:30 PM
Figure 2. Daily trends for chromium in Rinse 1 Tank, Rinse 2 Tank, and processed water.
11
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o>
c
o
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further helps to remove contamination. Plant; that operate the chromating line 24 hr/day will riot
have the benefit of overnight processing and may see higher contaminant levels than shown here.
The recovery system removes consi ierable amounts of chromium and other contaminants
from the rinsewater, rendering it suitable for use as a final rinse on the chromated parts. TDS
levels are reduced to below those for the tap
vater supply at QRD. A simple conductivity check
can be used as a water quality indicator, if recuired. The acidity of the processed water is
significantly lower than that of the fresh wate
supply. However, the lower pH of the final rinse is
not considered an issue by QRD and no product quality concerns have been raised in the 1 year
that this process has been in operation. Chromated parts have continued to meet QRD's and its
customers' quality requirements.
A few chromated and nonchromatec
parts were collected on the test day and retained on
an open tray for observation. After almost nine months, the nonchromated parts have gathered
rust spots, while the chromated (and zinc-plat
retained a continuous bright luster. Although
are that reusing the processed water as a rinse does not affect chromating quality.
3d) parts show no visible traces of rust and have
no surface microanalysis was performed, indications
13
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SECTION 3
POLLUTION PREVENTION POTENTIAL
Pollution prevention consists of wastje volume reduction and pollutant reduction. Waste
volume reduction refers to the reduction in volume of waste that has to be disposed of or treated.
Pollutant reduction refers to the amount of a gjven pollutant (chromium, in this case) that is
removed from the wastestream. The pollution
6-hr shift/day, 5 days/week, for 50 weeks/yr.
prevention estimation for this study is based on one
WASTE VOLUME REDUCTION
The source of waste in the chromating process is the wastewater that would be
generated during rinsing, in the absence of a recovery system. The chromating line rinse requires
approximately 5 gal/min continuous flow through the sprays. Based on one 6-hr shift/day,
5 days/week, for 50 weeks/yr of operation, 450,000 gal/yr of wastewater requiring treatment
would have been generated.
Because of the recovery unit, most of this water is recovered and reused. The only
wastestream is the still bottoms concentrate that has to be discarded. Currently, QRD periodically
discharges the still bottoms into the 500-gal sump tank. At a later stage, when this sump tank
was full, QRD ran the contents of the sump tank through the recovery system to distill it down to
approximately one 200 gal of concentrate. Th
The waste volume is thus reduced from 450,000 gal/yr to 200 gal/yr by using the
recovery system.
POLLUTANT REDUCTION
The main pollutant of interest, in this
the inlet and outlet pipes of the recovery systen
water) or the processed water (outlet water) Were
s concentrate was disposed of as hazardous waste.
case, is chromium. Water meters were installed on
. Each time samples from the Rinse 1 Tank (inlet
collected, the water meters were read. Based
14
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on these measurements, Figure 4 shows a plot of chromium concentrations in the inlet and outlet
waters as a function of the cumulative, amount of water flowing through the recovery system. The
integral area under the "Rinse 1" line indicates'the mass of chromium that would have been lost in
the rinsewater had there been no recovery sysjtem. The area under the "processed water" line
indicates the small amount of chromium that the recovery system is unable to recover from the
returned water. The difference between the tjvo areas (in units of mass) is the amount of chro-
mium prevented from going to waste. Areas in the graph were calculated by overlaying a finite
grid and measuring the number of squares under the concentration curve in the appropriate units.
Based on Figure 4, the difference in areas under the two concentration lines, and
therefore the amount of chromium recovered ih the 6-hr test shift, is 2,778 mg. On an annual
basis, approximately 1.5 Ib of chromium is prevented from going to waste as wastewater.
POLLUTION PREVENTION ASSESSMENT
As seen in the previous sections, the, waste volume is reduced by using the recovery
system. As far as pollutant reduction is concerned, 1.5 Ib of chromium are concentrated in
approximately 200 gal of still bottoms concentrate. True pollution prevention would require that
this concentrate be reused in the chromating tanks, but for QRD this is not possible because the
concentrate contains a mixture of blue, clear, ar
interchangeably on the chromating line. Metal
may be better able to reuse the still bottoms concentrate from the recovery system.
nd yellow chromate formulations that are used
finishers who use a single formulation at all times
15
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— / / , \ _
•Y™-—r™~r-™T
8O 1OO 120 14O 16O
Galldns of Water
Rinse 1 Cone. d Processed Water
Mass of Chromium in Rinse 1
Mass of Chromium in Processed Water
Figure 4. Chromium in
the inlet and outlet waters.
16
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I
SECTION 4
ECONOM
The economic analysis compares the
of generating and treating wastewater.
MAJOR OPERATING COSTS
C EVALUATION
costs of operating the recovery system to the costs
Table 4 shows the costs involved in operating with and without the recovery system.
Chemical costs, i.e., the costs of the chromate; formulations, are not considered because the same
amount of formulation is required in the chromate tanks regardless of rinsewater recovery. Costs
are calculated on an annual basis for operating one 6-hr shift/day (actual operation of the
chromating line), 5 days/week, for 50 weeks/yjar. The recovery unit is considered to operate
24 hr/day. Some auxiliary devices, such as the vacuum pump, operate for a fraction of the time
that the entire recovery unit is in operation and
Without the recovery system the main operating costs are as follows:
Fresh water supply. A continuous
required in Rinse 2, flowing courjtercurrent
their use is appropriately prorated.
5-gal/min flow of fresh tap water is
into Rinse 1.
Most of this water ends up as wastewater requiring treatment. Unit
costs for wastewater treatment were estimated from QRD's plant
records (see Appendix B). Wastewater treatment costs at QRD appear
to be somewhat higher than those normally associated with metal
finishing plants because of the njultitude of.processes that generate
wastewater at QRD.
With the recovery unit, the main operating costs are as follows:
Process water makeup. Althoug
and recirculated, there are some
approximately 50 gal/day of fres
Rinse 2 Tank.
most of the rinsewater is recovered
systemic losses for which
i water makeup is added into the
17
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TABLE 4. MAJOR OPERATING COSTS COMPARISON
Item
riual
Annual Amount
Unit Cost, $
Annual Cost, $
Without Recovery System
Water (rinse)
Wastewater treatment
With Recovery System
Water (rinse, makeup)
Water (cooling, makeup)
Waste disposal
^50,000 gal 4.65/1,000 gal
450,000 gal(a) 88.00/1,000 gal(a)
TOTAL
1 2,500 gal
12,500 gal
200 gal
4.65/1,000 gal
4.65/1,000 gal
350.00/55 gal
2,093
39,600(al
41,693
58
58
1,273
Energy
- electricity 6(
- steam 3
Maintenance
Labor
>,950 kW hr
,000,000 Ib
—
100hr
0.068/kW hr
0.004/lb
—
8.00/hr
TOTAL
4,145
12,000
1,200
800
19,534
(a) Plant-specific values at QRD. These costs are] highly plant-specific, and individual users should re-
estimate these costs for their own plants.
Cooling water makeup. Cooling
recirculated through a cooling tower
are made up with the addition o
water.
Waste disposal. Approximately
water required in the condenser is
Evaporative losses in this loop
approximately 50 gal/day of fresh
200 gal of still bottoms residue is
disposed of every year. This residue is RCRA-listed as hazardous
because it contains chromium metal. In plants that use only one
formulation on the chromating line, this disposal can be avoided
through reuse.
Energy. Electricity is consumed
unit's circulation pump (7.5 kW,
during the operation of the recovery
24 hr/day), vacuum pump (5.5 kW,
3 hr/day), the cooling water circjlation pump (10 hp, 24 hr/day), and
the cooling tower fan (5 hp, 24 hr/day, 25 weeks/year). The steam
consumption of 500 Ib/hr (24 hrl'day) was based on the recovery sys-
tem manufacturer's estimated efficiency of 1 Ib of steam for every 1 Ib
of water processed (a circulation of approximately 1 gal/min is
maintained through the recovery system).
Maintenance. Maintenance costs are a general estimate based on
items such as changing the mairi seal in the circulator pump and the
discharge tank air filter once a year, a new grease fitting every
2 months, and any other miscellaneous maintenance.
18
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Labor. Estimated additional
approximately 2 hr/week.
labor for running the recovery system is
The savings in operating costs therefore are $22,159/yr.
CAPITAL COST
The purchase price of the model installed at QRD is quoted as $78,000. The installation
cost (piping, holding tanks, etc.) at QRD was estimated at $5,000 including about 16 man-hours of
labor. Another associated cost is the purchase of the cooling tower and holding tank (for the
condenser water) for $4,000. The total capital cost is $87,000.
ECONOMIC ASSESSMENT
Based on the above capital cost ($87,000) and the reduction in annual operating costs
($22,159), the payback period for the recovers system can be estimated by:
payback in years =
capital cost
annual reduction in operating costs
This gives a payback period of 4 years. Therefore, the recovery system in addition to providing
good quality rinsewater and reducing waste, also results in economic benefits for the user.
19
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SECTION 5
QUALITY ASSURANCE
A Quality Assurance Project Plan (QAPP) prepared prior to testing outlines the quality
assurance (QA) requirements for the study. The experimental design, on-site testing, and
laboratory analytical procedures are covered. [The QA objectives outlined in the QAPP are
discussed below. ~
ON-SITE TESTING
On-site testing was performed as pldnned except for the following variations. Because
only blue chromate solution was being used on the line that week, the lines did not have to be
purged and a purge water sample was not colljected. Sample completion was 100% at all locations
except the purge water line. No field duplicates were collected for this study because none of the
tanks had any suspended particulates and the
aqueous solutions were homogeneous. All sampfes,
including the still bottoms, were free of suspended solids.
QRD had changed the configuration of the system since the QAPP was written so that
the sump tank was no longer in the rinsewateJ recovery loop but was just being used as a
repository for the still bottoms that were evacuated periodically and for any purge water that might
be generated during formulation changes. Although samples were collected from the sump tank
(see Appendix C for the analysis) as planned, these samples no longer are an important part of the
evaluation, other than as a general indicator o
On the test day, the filter press (part
down and the zinc plating operation, which ge
the distillation residue and purge accumulation.
of the wastewater treatment plant) at QRD broke
lerates wastewater, had to be shut down, such that
a continuous supply of zinc-plated parts available for chromating could not be maintained.
Therefore a single barrel of zinc-plated parts w:as circulated through the chromating line to simulate
contaminant dragout into the rinse. This did n|ot affect the testing because the prime interest was
the rinsewater loop and not the chromating itself. However, slightly more chromate (hexavalent),
that otherwise would have otherwise been boiind on the parts, can be expected to have made its
way into the rinse.
20
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All samples were collected as detailed in the QAPP. Samples were collected in
precleaned plastic bottles. Nitric acid preservative was added to bottles collected for metals
analysis. All sample bottles were packed wittji ice in a cooler and shipped by overnight mail to the
analytical laboratory.
LABORATORY ANALYSIS
Analysis of the samples was performed as planned (using standard EPA methods for
water and wastewater analysis) and analytical completion was 100%. Tables 5 and 6 list the
precision and accuracy, respectively, of the analysis for each matrix (water and concentrate). The
water matrix consisted of the rinsewater and Drocessed water; no distinction was made between
the two because their composition was relatively similar. Precision and accuracy are within the
acceptable range of ± 25%. The native sample result in Table 6 indicates the regular sample
result including any dilution by the laboratory. Detection limits also are listed, and all laboratory
blanks were below detection. The field blank (tap water) analysis shown in Table 2 indicates no
extraneous contributions to the analysis excerit for TDS and conductivity. This is a reflection of
TABLE 5. PRECISION OF ANALYSIS
Parameter
Water Samples
Chromium
Chromium
Zinc
Zinc
TDS(b)
Conductivity'01
Conductivity'01
pH(d)
Concentrate Samples
Chromium
Zinc
TDS""
Conductivity'01
pH(d)
Detection
Limit
10
10
10
1O
1
1
1
0.01
10
10
1
1
0.01
Sample
# Regular, fjg/L
|
W-R1-1 2,570
W-R2-5 1,350
W-R1-
1 4,500
W-R2-5 3,970
W-R1-3 372
W-R1-6 312
W-R2-
W-R2-
C-ST--
C-ST-'
^ 160
t 5.22
1,396,000
1,758,000
C-CCTj 25,110
C-ST-3 10,550
C-ST-3 3.08
Duplicate, jjg/L Precision, %(al
2,680
1,280
4,660
4,030
347
312
161
5.23
1,431,000
1,782,000
25,900
10,540
3.08
4.3
-5.2
3.6
1.5
-6.7
0.0
0.6
0.2
2.5
1.4
3.1
-0.1
0.0
(a) Precision = [(Regular - Duplicate) x 100]/[(Regu ar + Duplicate)/2].
(b) Units are mg/L.
(c) Units are //mhos/cm.
(d) As measured in Standard Units.
21
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TABLE 6. ACCURACY OF ANALYSIS
Parameter
Water Samples
Chromium
Chromium
Zinc
Zinc
TDS(b)
Concentrate Samples
Chromium
Zinc
Iron
TDS(b)
Sample #
W-R1 -1
W-R2-5
W-R1-1
W-R2-5
W-R1 -3
C-ST-1 .
C-ST-1
C-ST-1
C-CCT
Native Spike
Result, //]g/L Level, //g/L
256.S
1,351
500
500
450.4 500
396.6 500
37.2^ 1,000
1,396
1,758
,
500
500
749.7 500
1,255.3, 1,000
Matrix
Spike, //g/L
751
1,839
965
922
971.6
1,919
2,283
1,244
2,224.2
% Recovery'31
98.8
97.6
102.9
105.1
93.4
104.6
105.0
98.9
96.9
1 • ' -• - ' ' ''."--.- ' " " •"• • ' f_. '__ i_ ^ IIIII^J l 1 "-L !_.___ ^z
(a) Recovery = (Matrix Spike - Native) x 100/Spike Level.
(b) Units are mg/L. I
the high levels of dissolved solids normally found in Thomaston's (QRD's) well water supply.
Holding time requirements for all the analytes were met by the laboratory. Standard EPA methods
were used for the analysis of metals (EPA Methods 6010, 3010), pH (EPA Method 150.1),
conductivity (EPA Method 120.1), and total dissolved solids (EPA Method 160.1). Calibrations
were performed as required by the standard methods. Appropriate dilutions were made for data
that were outside the calibration range.
LIMITATIONS AND QUALIFICATIONS
An important aspect of pollution prevention is the recovery and reuse of the pollutant of
interest, namely chromium in this case. However, because QRD uses three different formulations
on the chromating line, the recovered chromium concentrate cannot be reused. Therefore the
reuse aspect of the application could not be evaluated. This is an operational rather than a
systemic limitation. At plants which use a single formulation on a line, the testing indicates that
reuse should be possible. Zinc and iron levels
monitored if such reuse is planned.
in the recovered concentrate should be carefully
22
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SECTION 6
I
CONCLUSIONS AND DISCUSSION
The recovery system evaluated in th(S study provided a continuous supply of good quality
rinsewater to the chromating line at QRD. Recirculation prevents nearly 450,000 gal of water from
going to waste every year. Contaminants remjoved from the circulating water include chromium,
zinc, and other dissolved solids. Contaminant^ are concentrated in a tiny wastestream (approxi-
mately 200 gal/yr) and disposed. Because QRD uses three different chromate formulations on a
single chromating line, this concentrate could raot be reused. At plants that use a single
formulation, reuse may be possible, provided that the levels of zinc and iron do not increase to a
point where they affect the chromating qualityl.
Because wastewater (requiring treatment) is not generated, the recovery system causes a
reduction in wastewater treatment costs. Ovejrall operating cost reduction depends on the
individual user's expected wastewater treatment costs. At QRD, the return on investment was
sufficient for the initial capital outlay to be recovered in approximately 4 years.
This recovery system is easy to install and operate on existing process lines. Other than
chromating operations, the system has potential for application to any process line that generates
wastewater (see Appendix D). Unlike other systems such as electrodialysis or reverse osmosis,
which are prone to fouling and require considerable maintenance, or ion exchange, in which the
resin has to be regenerated periodically, this evaporation/distillation system is relatively operator-
free, requiring minimal operator involvement. One limitation is the relatively high energy (steam)
requirement necessitated by the heat requirements for distillation. Future models that are being
developed are expected to have a more energy efficient design.
23
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SECTION 7
REFERENCE
I
U.S. Environmental Protection Agency. 1992| EPA's 33/50 Program Second Progress Report.
TS-792A. Office of Pollution Prevention and toxics, Washington, DC.
24
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APPENDIX A
MANUFACTURER S DESCRIPTION OF THE
VACUUM EVAPORATION/FLASH DISTILLATION SYSTEM
SYNOPSIS OF THE HISTORY,
PERFORMANCE
PLANNED USE OF
THE CAST™ CHEMICAL RECOVERY SYSTEM
AT QUALITY ROLLING &
DEBURRING, THOMASTON, CT
PURIFICATION
(CPS)
PREPARED BY: CELLINI™
SYSTEMS, INC.
Westfield, MA
DATE: December 6, 1991
25
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Controlled Atmosphere Separation Technology, CAST™, utilizes
various aspects of flash distillation and vacuum evaporation technol-
ogies in conjunction with a patentjed liquid/vapor separation system to
recover and reuse aqueous-based chemical solutions and/or process water.
The systems are custom-engineered for each application to provide closed
loop or zero discharge operation wlken possible. In many electroplating
applications, both plating chemistry and rinse water can be recovered
for immediate reuse.
A CAST™ Chemical Recovery System is currently in place and oper-
ating at QUALITY ROLLING AND DEBURRING CO., INC. (QUALITY) in Thomastort,
CT. The system ,was used initially to recover the process water from a
mechanical zinc plating process for] immediate reuse, and return a highly
concentrated aqueous-based product for further reduction.
On October 3, 1991, after five months of evaluation,_ the CAST™
system was removed from its application on the mechanical zinc plating
operation. The system was cleaned and reconfigured for use in a zero
discharge scheme for a chromating^japplication. The water .produced by
the system was for immediate reuse in the chromating rinse tanks. The
recovered chromating solution was Ho be returned directly to the chro-
mating bath. Absolutely no measurable quantity of chrome -could be
tolerated in the rinse water. This was QUALITY'S prerequisite to pur-
chasing CPS' CAST™ system for use in their planned Zero Discharge,
Toss/Catch Action Chromating installation.
Chromating rinse water was simulated by combining city water with
MacDermid CT-11. The simulated rinse water contained 150 PPM of chrome.
The simulated rinse water was introduced into the system at room
temperature. The system was operated at approximately 40 GPH. The
temperature of the process solutiorl exiting the spray head was approxi-
mately 115°F. The temperature of the process solution entering the heat
exchanger was estimated to be 100°F. The calculated heat input was
350,000 Btu per hour. The vacuum was maintained at 0.8 psia ± 0.3 psia.
The system was operated at these conditions for four hours, producing
eight product water discharges of 20 gallons each. The total output was
160 gallons. Three equal samples were taken from each discharge, one
from the beginning, middle and end] of the discharge. The samples were
mixed together to form an average sample from each discharge.
The eight samples were analyzed by QUALITY'S technician using their
Flame AA. Each sample was analyzed in conjunction with two control
samples. The control samples consisted of 2 PPM standard chrome solu-
tion, distilled water, and retained solution from the previous sample.
One retain from the previous test was used in the next test as a control
sample in all testing with the exception of the first, which consisted
of two identical samples, a 2 PPM chrome, standard and two distilled
water samples. The remaining seven tests consisted of one actual
sample, one previous retain and a Randomly selected control. The first
two discharge samples contained 1 PPM chrome. However, inconsistencies
were noted in the control samples during the first, second and third
tests. After calibration of the Flame AA to a 1 PPM chrome standard
instead of the previous 10 PPM chro|me standard, the third test indicated
-Page One-
26
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levels' of chrome less than the lowest limit of detection for the Flame
AA. All remaining samples tested! showed levels of chrome lower than the
limit of detection. All remaining control samples indicated appropri-
ately. During this procedure, [the operator was not informed of the
identity of the samples or the possible chrome content.
The system was restarted the next day and operated at 30 GPH on an
extremely concentrated chromic acid solution. After four hours of oper-
ation, no visible color could be j detected in the product water. Color
was observed to be readily visible in product water containing 2 ppm
chrome generated from process solutions containing 150 ppm chrome. The
observed lack of color in the product water generated from the highly
concentrated chromic acid solution indicated the system's ability to
produce quality water from highly concentrated chromic acid solution,
or inversely, produce highly conpentrated chromic acid solutions from
low concentration rinses. j
The CAST™ system produced rpnse water with chrome concentrations
below the lowest level of detection, for the. Flame AA instrumentation
employed. These results were verified by an . independent laboratory
operated by one of the largest (suppliers of plating solution in the
country. As a result, in conjunction with five months of' previous
operation on their mechanical zijnc plating process, QUALITY purchased
the CAST™ system on November 5, 1SJ91.
j
QUALITY will be integrating) the CAST™ system into their .planned
Toss/Catch Action Chromating line. Production kickoff is anticipated
during the first quarter of 1992. The line is designed to chromate
carbon steel hardware ten hours a! day, five days a week. Please refer
to attachment for a detailed description of the proposed Toss/Catch
Action Chromator. The CAST™ system will obtain its feed from the rinse
water storage tank. The recovered water will be returned to the same
tank, and the recovered chromating solution will be returned to the
appropriate chromating solution storage tank. Reusing the process water
and chromating solution will eliminate the cost of lost chromating solu-
.tion, rinse water, waste treatment of the rinse water and disposal of
the waste generated from the treatment of the rinse water. Addition
ally, the need for a chrome sewer discharge permit will be eliminated.
In-keeping with the corporats philosophies of environmental aware-
ness and excellence in engineering, the staff at CPS, lead by the
president and founder, John V. Cellini, forged ahead to produce the next
generation CAST™ system. Using [the information obtained through the
field placement of the first CASjT™ system at QUALITY and hundreds of
man-hours of in-house research and development, substantial improvements
have been developed for the next generation CAST™ system, Version 2.0.
CAST™ system, Version 2.0 has been designed around a revolutionary
energy recovery system. This sjystem will allow the Version 2.0 to
operate on 14% of the energy required to operate the previous model.
This translates to an operational -energy cost reduction of 86%, thus
reducing the quantity of fossil fuels required for operation and further
enhancing the environmental and financial impact of the system.
-Pc
ge Two-
27
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Further system improvements include the introduction of a fiber-
glass process vessel with optional TFE or PVDF coatings, more effective
vapor/liquid separation, steam protection and control systems, and
simplified valves and controls.
Additionally, a cost reduction program based on the use of engi-
neering plastics, alternate fabrication techniques, and a completely new
control system has reduced the manufactured cost,_ thus reducing the
selling price and the customer's payback period.
The staff of GPS believes that
revolutionize the current marketpl
recovery of chemical- solutions once
the CAST™ system, Version 2.0 will
ace by turning into reality the
thought to be impossible or econom-
ically unreasonable to recover; and feels that, with continuing develop-
.ment and dedication to excellence in environmental products, the future
is a bright and clean one.
-Page
Three-
28
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ARPENDIX B
ESTIMATION OF WASTEWATER TREATMENT PLANT OPERATING COSTS
AT QUALITY ROLLING & DEBURRING CO.
Wastewater treatment unit costs were estimated from plant records at Quality Rolling &
Deburring (QRD) Co. Between January 1 ajnd June 30, 1993, QRD treated 2,580,100 gal of
wastewater in their on-site treatment plant.
Costs incurred for this period were:
B Treatment chemicals, $79,226
» Labor, $67,186
• Sludge disposal, $80,416.
The total cost was $226,828, giving an estimate of $0.0879/gal or $88/1,000 gal of wastewater
treated.
29
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APPENDIX C
ANALYSIS OF SAMPLES COLLECTED FROM THE SUMP TANK
Sample No.
C-ST-1
C-ST-2
C-ST-3
C-ST-4
C-ST-5
Time
9:30 a.m.
1 1:00 a.m.
12:30 p.m.
2:00 p.m.
3:30 p.m.
Cr
mg/L
1,396
1,408
1,441
1,429
1,434
Zn
mg/L
1,758
1,875
1,885
1,910
1,948
TDS
mg/L
12,650
12,550
12,430
13,120
1 2,500
Cond.
//mhos/cm
10,490
10,480
10,550
10,530
10,470
PH
3.03
3.05
3.08
3.07
3.08
30
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APPENDIX D
MANUFACTURER'S DESCRIPTION! OF OTHER POTENTIAL APPLICATIONS
FOR THE VACUUM EVAPORATION/FLASH DISTILLATION SYSTEM
31
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SUMMARY OF CAST™ CAPABILITIES
Controlled Atmosphere Separation Technology, CAST™, by Cellini
Purification Systems, Inc. (CPS)j has been successful in providing
reusable rinse water and recovering from the plating solutions of
various metal finishing operations the following elements:
* nickel chloride
* nickel sulfate
* nickel sulfamate
* zinc chloride
* cadmium cyanide
* silver cyanide
* gold cyanide
* zinc cyanide
* brass cyanide
* chromic acid
Additionally,
containing:
sewage
particulate matter
dissolved organic c
CAST™ systems have successfully purified water
nd ionic contaminates
Systems have separated water from oils, recovered etchants,
cleaners, solvents (chlorinated hydrocarbons) and process chemicals
for reuse, and concentrated platjjng solutions, spent detergents and
end-of-pipe waste streams for disposal.
CAST™ systems also are capable of generating ultra-pure water
from city water sources and potable water from sea water. CAST™
systems may be utilized virtually1 anywhere ultrafiltra.tion, reverse
osmosis, ion exchange, electro
-winning, electrodialysis and/or
current data indicates that the
conventional chemical precipitation waste treatment is used. Most
2nergy cost per gallon of effluent
processed in most cases ranges from $0.004 to $0.01.
Finally, CAST™ technology can be utilized in the mining
industry, within co-generating power plants, and to de-alcoholize
wine and beer. And we are discovering new applications almost
every day.
DATED:
August 18, 1993
Cellini™ Purification
P. O. Box 942
Westfield, MA 01086-0942
Systems
32
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