United States
Environmental Protection
Agency
National Risk Management
Research Laboratory
Cincinnati, OH 45268
Research and Development
EPA/600/SR-95/126 August 1995
vvEPA Project Summary
Field Testing and Evaluation of
Zerpol® Technology at Pioneer
Metal Finishing
Hanna J. Saqa, Daniel J. Watts, Mohammed Elsaady, and Johnny Springer
The U.S. Environmental Protection
Agency's Waste Reduction Innovative
Technology Evaluation (WRITE) Pro-
gram has an objective of evaluating
technologies that have potential for
waste reduction or pollution preven-
tion as compared with other currently
used approaches. The Zerpol1 process,
as used in metal plating operations,
captures all aqueous effluent from the
manufacturing operations, conditions
the effluent to remove any metal or
cyanide that may be present, and per-
mits the reuse of the conditioned water
in rinsing operations. About 30% of the
recovered water is fed into the plant
boiler to generate distilled water for
critical rinsing. The goals of this study
were to confirm that the quality of the
water derived from the Zerpol process
is appropriate for the intended reuse,
and that the process is safe, and to
estimate the economics of the installa-
tion and use of the process as com-
pared to other alternatives.
The evaluation was carried out at Pio-
neer Metal Finishing in Franklinville,
NJ. Field observations and sample col-
lection were carried out over a 1-mo
period. Based on the observations,
which included determination of the
content of metals and solids at selected
sampling points throughout the sys-
tem, it is concluded that for facilities
similar to those where the evaluation
was conducted, the Zerpol system pro-
Mention of trade names or commercial products does
not constitute endorsement or recommendation for
use.
vides significant advantages and is in-
sensitive to fluctuations caused by
acidic or basic bath dumps into the
system. At Pioneer, approximately 80%
of the process water is reclaimed and
recirculated. Estimation of the econom-
ics suggests that the incremental cost
of about $120,000 for a 2000 gal/day
Zerpol system results in savings in
chemical usage, labor and maintenance,
and waste disposal costs providing a
payback period of 5.3 yr. While the sys-
tem eliminates effluent discharges at
the site, it does produce a metal sludge
stream that facilitates metal recovery
through smelting, and a high solids
content stream from boiler blowdown.
The system eliminates the use of chlo-
rine for cyanide destruction, eliminat-
ing that source of chlororganic
materials emitted from the site.
This Project Summary was developed
by EPA's National Risk Management
Research Laboratory, Cincinnati, OH,
to announce key findings of the re-
search project that is fully documented
in a separate report of the same title
(see Project Report ordering informa-
tion at back).
Introduction
The Waste Reduction Innovative Tech-
nology Evaluation (WRITE) program had
an objective of identifying and evaluating
technologies with potential for waste re-
duction or pollution prevention as com-
pared with other currently used
technologies. The Zerpol process, as ap-
plied to waste waters from metal finishing
operations, has that potential based upon
-------
claims and reports of its performance. The
process involves the capture of all aque-
ous effluent from the manufacturing op-
eration, conditioning of this effluent to
remove any metals or cyanide that may
be present from rinsing procedures, and
the reuse of the recovered water for rins-
ing. About 30% of the recovered water is
fed into a boiler to produce distilled water
for critical rinsing. Boiler blowdown main-
tains the salt level in the recirculated wa-
ter at a level acceptable to the metal
finishing process. Thus, the use of the
Zerpol process has the objective of per-
mitting continued recycling and reuse of
water in the manufacturing process. Sys-
tem water loss due to boiler blowdown
and evaporation from the process tanks is
made up by fresh water supply.
The Zerpol process does produce at
least two waste streams, a metal hydrox-
ide concentrate that results from the con-
ditioning of the process effluent (suitable
as a resource for metal recovery by smelt-
ing or similar operations) and blowdown
from the boiler (a concentrated solution of
soluble salts). In some instances, waste
oil may accumulate at the surface of the
effluent storage tanks. This oil is skimmed
and disposed of as waste.
A previous EPA-supported study by re-
searchers at the University of Central
Florida [2] evaluated the effectiveness of
the Zerpol process as a waste manage-
ment technique for the metal finishing in-
dustry. That study concluded that there
were potential applications for the pro-
cess in certain segments of the metal
finishing industry. However, the report
raised some questions that could not be
answered based on the evaluation that
was carried out then. These questions
included uncertainties regarding rinse wa-
ter quality, boiler economics and opera-
tion, product quality, and safety.
The purpose of this project was to con-
firm and extend the previous study of the
Zerpol process to provide information
about its waste reduction potential, opera-
tional implications, safety issues, and eco-
nomics.
The evaluation was carried out at Pio-
neer Metal Finishing, Inc. in Franklinville.
At the time of the study the facility oper-
ated one shift per day, five days per week.
Pioneer Metal plates a variety of metal
objects, emphasizing copper, nickel, and
chromium plating operations. All parts are
rack plated. All parts are cleaned, acid
dipped, copper plated and nickel plated.
Forty percent receive chrome. The base
metals that are plated are steel, brass or
zinc diecast. Components for electric
equipment, automobile parts, and refrig-
eration and plumbing parts make up 80%
of the work load.
During the field evaluation period of
about one month, the shop was producing
approximately 3,000ft2 of plated surface
per shift. The parts varied from small
screws up to items with 0.8ft2 of surface
each. The plating lines and the Zerpol
system are shown schematically in Fig-
ures 1 and 2.
The Zerpol system has been in place at
the facility since 1981. This technology
allows the conditioning and reuse of pro-
cess water. The Zerpol technology could
be useful not only for the metal finishing
industry, but also for many types of water-
using industrial operations. In this system,
aqueous effluent is accumulated in pro-
cessing tanks to allow conditioning in a
batch mode. In the metal finishing appli-
cation, conditioning is a step-wise pro-
cess.
Initially, an active oxygen compound,
reported to be hydrogen peroxide [1], is
added, as needed, to oxidize cyanide ions.
(Although possible compositions of the
active oxygen compound and the reduc-
ing agent are reported in the literature,
Zerpol Corporation indicates that the na-
ture of these formulations is proprietary
information. Therefore, during this investi-
gation, no effort was made to determine
their exact compositions). This step is fol-
lowed by the addition of a reducing agent,
reported to be sodium hydrosulfide [1], to
reduce chromium, if present. Sodium hy-
droxide is added for pH adjustment to
induce precipitation of metals.
After a 2- to 3-day settling period, the
clarified water is transferred to a storage
tank and used in the shop process as
needed. Approximately two-thirds of the
recovered water is used in the process for
non-critical rinsing and about one-third is
directed to the boiler. The steam gener-
ated is used for heating process baths.
The condensate is used in the plating
process for critical rinsing and partially for
boiler feed to reduce solids build up in the
boiler. The net effect is the near total
reuse of the effluent stream, thus attain-
ing a zero discharge condition at the loca-
tion.
The dissolved solids in the clarified re-
cycled water are kept within acceptable
limits by controlling the boiler blowdown.
The residual solids streams generated from
the precipitation process and from the
boiler blowdown are sent off site for reuse
or disposal. The metal contents are re-
claimed by smelting.
Because effluent conditioning is done in
a batch mode, one tank at a time, ad-
equate tank volumes are required for col-
lection of the raw wastewater and for stor-
age of the clarified effluent prior to reuse.
The frequency of batch conditioning at
Pioneer is dependent upon production
schedules; initially it averaged about once
every five days or approximately five times
per month. The capacity of each of the
two effluent processing tanks is 25,000
gal compared to a reported design pro-
cess usage rate of about 5,000 gal/day.
The (clarified) water storage tank holds
50,000 gal. Over the last few years, the
process flow rate has been greatly re-
duced. At the time of the study, it was
less than 2,000 gal/day.
Due to the large holding capacities of
the tanks, the Zerpol system can handle
process dumps such as caustic, acid, and
other cleaners without noticeable detrimen-
tal effects. Some processes may need
de-ionized water for the most critical rins-
ing, in addition to the use of the conden-
sate produced from the boiler. This
condensate is controlled to have a TDS of
less than 1000 mg/l. Condensates with
higher dissolved solids contents are auto-
matically switched over to the clarified
water storage tank.
Two principal concerns associated with
the process relate to the successful op-
eration of a boiler with an input TDS of
over 5000 mg/l, and whether the produced
condensate is satisfactory for critical rins-
ing requirements and for acceptable prod-
uct quality in the plating operation. A
sufficient demand for steam will help jus-
tify the energy input for the operation of
the boiler. Water conservation and flow
reduction are also key factors in the suc-
cess of the system.
System Performance
Evaluation Data
Several specific sets of field data were
collected at the facility to measure and
describe the performance of the Zerpol
process and to define more closely its
areas of applicability. Analysis of the col-
lected data addresses the following five
topics: 1) Whether the quality of the recir-
culated water is appropriate to maintain
the plating process effectively and effi-
ciently; 2) Whether the Zerpol process
yields a metal concentrate that can be
used for metal recovery through smelting
or other standard metal recovery technol-
ogy; 3) Whether unsafe levels of hydro-
gen cyanide form within the Zerpol system;
4) Whether the use of a boiler to maintain
an acceptable TDS level in the recircu-
lated water is a sound, practical and eco-
nomically feasible alternative; 5) Whether
the economics of the installation and op-
eration of the Zerpol system are favor-
-------
I
I
I
to
Q.
.1
u.
-------
111
?si
iS^
UlQ- ra
UJ
^1
1
3
^
apiueAo ezipixo oj ZOZH ^
-j^sEw^aj oj a^/nsojp/H mnipos as
n-l
ie}3iu a}B}idi3ajd oj HOBN ^W^ yd tsnfPV •
/^T\
V^J
1
I
s.
f
55
j
CD
*l 1
$ -8
Ul 10
Bto §>^g
^^ 8 g c
"-2 Q t cu
2 5 ^"§
Ul C
3 Si
R; 1
(D
/
t
L
^
4
«c
. .§1
QJ CD
r-C 0)
ou_
0^
«58>
-S "c
o ^-
Q
s
§
i
Ul
CD
\
¥•
£
5
s
I
to
•6
.O
U)
to
-Q
I
N
1
I
CO
u.
-------
able, particularly in comparison with the
costs of using other waste management
options.
Field Sampling and Operating
Data Gathering
Three types of data were gathered dur-
ing six-day tests conducted over a 32-day
period: 1) Composite stream samples for
chemical analysis; 2) Actual flow rate mea-
surements of the generated effluent, recir-
culated water, steam condensate and
boiler fuel gas; 3) Historical operating and
maintenance data on the present Zerpol
System and the system that preceded it,
a system that involved precipitation of
metal sludges and discharge of the treated
aqueous effluent.
For each test, composite samples of
the process and of the Zerpol streams
were taken. System flow rates, namely
process effluent flow, and the pumping
rates of clarified water and of the sludge
were measured by capturing the flow in a
container and by timing the flow with a
stop watch. The boiler feed was mea-
sured by an actual water meter.
Samples were taken from ten sampling
points and analyzed for cyanide ions, cal-
cium, magnesium, copper, nickel, chro-
mium, iron, zinc, cadmium, phosphorus,
total solids, total suspended solids, total
dissolved solids, and pH.
The analytical data and volume flow
measurements are used to determine
mass loading entering and leaving the
Zerpol system, and by difference, the
amount captured by the Zerpol system.
Similarly, the quality of the condensate
was determined, as well as the composi-
tion of the boiler blowdown. The boiler
operation was monitored during five work-
ing shifts. The total volume of water fed
into the boiler was metered. The volume
of boiler blowdown was determined by
metering and by calculations. Composite
samples were analyzed.
Because concern was expressed in the
previous study about levels of hydrogen
cyanide potentially produced in the Zerpol
process, air samples were taken, using
OSHA standard procedures, at the first
point open to the atmosphere after mixing
of acid streams and cyanide ion bearing
streams. These air samples were taken at
the mixing tank ahead of the first holding
tank, where analytical measurements of
the pH and cyanide content of the water
have also been made. Air samples were
analyzed for hydrogen cyanide.
Because Pioneer claims that the Zerpol
process continues to operate well even
when process baths are dumped, samples
and measurements were taken before and
after the occurrence of these extreme con-
ditions to demonstrate whether heavier
inorganic loadings interfere with the qual-
ity of the recirculating water.
To address the issue of potential prob-
lems with foaming in the boiler that were
raised in the previous report on the pro-
cess, the feed water to the boiler was
sampled before and after addition of the
defoaming agent and evaluated according
to the Standard Test Method for Foam in
Aqueous Media (Bottle Test), ASTM
D3601-88.
It should be noted that Pioneer fre-
quently reported discharge violations while
the former continuous discharge treatment
system was in operation from 1975 to
1981. These violations were a primary
reason the previous treatment system was
replaced and there have been no such
incidents since the Zerpol system became
operational.
Since the mid-eighties, shop manage-
ment has substantially reduced the total
use of water from the previous 5,000 gal/
day to less than 2,000 gal/day. Waste
minimization initiatives such as the reuse
of dragouts, have been very effective.
While the previous system required rela-
tively large volumes of water for most
effective operation, the Zerpol system uses
substantially reduced water volumes and
has encouraged and justified additional
pollution prevention efforts. In 1989, the
shop operation switched from two per day
to one shift starting at 6:00 AM and end-
ing at 2:30 P.M.
The operation of the Zerpol system and
the boiler were fine tuned to match the
requirements of the plating process. The
25,000-gal effluent processing tank that
used to hold the effluent for five work
days now holds effluent for about 18-20
work days. This means that the quantity
of chemicals used to precipitate the metal
hydroxides in the effluent processing tanks
has been greatly reduced.
The boiler serves two purposes: It pro-
vides 10-psig steam to heat the plating
baths. The condensate is used as a source
for rinsing and for boiler feed water when-
ever excess condensate is available. It is
also a means of controlling the level of
solids in the recirculated process water.
The solids are removed from the system
through boiler blowdown. For this applica-
Table 1. Summary of Process Streams Chemical Analyses for Metals and Solids
Sample
Point
\
/Wafer/a
Analyze
CN
TDS
Ca
Mg
Cd
Cr
Cu
Fe
Ni
Zn
P
S-2
Effluent
Tank
Inlet
[mg/l]
I
d
16.63
9820
19.24
0.99
0.26
22.23
11.17
22.22
71.86
27.83
24.91
S-3
Effluent
Processing
Tanks
[mg/l]
36.1
7820
13.94
0.57
<0.003
42.14
27.89
48.68
201
84.35
19.19
S-4
Clarified
Water
Tank Inlet
[mg/l]
2.69
8380
22.9
0.73
<0.003
2
2.9
2.01
10.1
0.92
<4.69
S-5
Sludge
Tank
Inlet
[mg/l]
245
8620
137
11.2
<0.235
538
445
723
3628
1434
189
Boiler
Feed (S-6)
Clarified
Water
[mg/l]
2.18
8329
16.94
0.9
<0.003
1.7
1.32
2.05
28.26
0.76
<4.86
Boiler Feed
(S-6)
Condensate
[mg/l]
3.21
725
<8.81
<0.095
<0.008
23.36
0.24
0.47
3.73
0.16
<4.69
S-7
Boiler
Blowdown
[mg/l]
18.53
85146
74
1
1.25
<0.008
236
10.08
5.65
52.57
2.3
9.62
S-8
Steam
Condensate
Return
[mg/l]
0.814
57.2
<8.09
<0.08
<0.008
0.12
0.16
0.28
<1.25
0.12
<5.98
S-9
Make Up
[mg/l]
<0.01
60
<8.09
0.982
<0.003
<0.046
<0.02
4.99
<1.25
0.08
<4.69
Waste Mil.
In Sludge
1,000 Sq. Ft.
Plated Area
[lb/1 000ft2]
_.
—
0.058
0.0047
0.000099
0.23
0.19
0.30
1.53
0.60
—
CN in air at Process Effluent Tank: 0.058 mg/rrf.
CN in air at Boiler Blowdown Sump Surface: 0.101 mg/m3.
-------
tion, the boiler capacity and blowdown
frequency are sufficient to keep the total
dissolved solids in the recirculated water
at less than 10,000 ppm.
Summary of the Results
Table 1 shows that the average IDS of
the clarified recirculated process water is
about 10,000 ppm; of the steam conden-
sate is about 500 ppm; of the boiler
blowdown is 100,000 ppm. This table also
shows that the metals concentration of
the recirculated water is higher than what
is allowed for discharge into a typical
POTW, e.g. Ni is 10.1 ppm compared
with an allowable limit of 3.98 ppm. The
cyanide concentration is 2.69 ppm com-
pared with the limit of 1.20 ppm. Treat-
ment to levels within the allowable limit
may be possible, but at much higher cost,
may not be economically attractive. The
observed levels are routinely maintained
by Pioneer because they are economi-
cally achievable and do not negatively af-
fect their processes.
Table 2 shows that the clarified water
recirculation rate is about 1,700 gal/day.
This is much lower than the initial system
design rate of 5,000 gal/day. Effluent flow
rate is in the range of 3.36-3.82 gpm.
About 37% of the recirculated water is
diverted through the boiler. Boiler
blowdown averages about 0.20 gpm. The
boiler generates steam to the process at
an average condensate equivalent rate of
1.35 gpm. Average heat delivery to the
process from the steam is about 6.55 x
105 Btu/hr. Boiler thermal efficiency based
upon heat delivered to process compared
to heat energy input to boiler is about 39-
40%. The daily energy cost to run the
boiler is in the range of $104-127/day.
Table 3 shows that the operating cost
of the Zerpol system is about 1/3 that of
the previous system, however; the installed
cost of the Zerpol is nearly two times that
of the previous system.
Conclusions
The Zerpol zero discharge system can
be used successfully at metal finishing
Table 2. Operating Data of the Zerpol Effluent Processing System
Test Series
Date
Test Number
1
4/14/92
1
1
4/15/92
2
1
4/16/92
3
2
5/14/92
1
2
5/15/92
2
Five
Day
Average
Clarified Water
Total Flow/24 hr:
Flow During Daytime
to Process:
(Average Flowrate)
* Flow During Night
to Boiler:
(Average Flowrate)
% of Clarified Water
Passing through Boiler:
Boiler Slowdowns
Average Flowrate:
N° Blwdns.-Minutes
Ea.-Gal Ea. During
Daytime:
During Nighttime:0
1747.4 gal
1079.4 gal
(2.57 gal/min)
668 gal
(1.59 gal/min)
38%
0.28 gal/min
3/1 min/39.2gal
0/0/0
Steam from Boiler (as Condensate}
1.18 gal/min
During Daytime to
Process:
Nighttime to Storage Tank: 1.59 gal/min
Average Flowrate (24 hr.): 1.385 gal/min
Average Heat in Steam
Flow to the Process:
1592 gal
949.2 gal
(2.26 gal/min)
642.6 gal
(1.53 gal/min)
40%
0.14 gal/min
2/1min/29.4gal
0/0/0
1.26 gal/min
1705 gal
1058 gal
(2.52 gal/min)
647 gal
(1.54 gal/min)
38%
0.13 gal/min
2/1min/27gal
0/0/0
1.28 gal/min
6.72 *105Btu/hr
1.53 gal/min 1.54 gal/min
1.395 gal/min 1.41 gal/min
6.77 "105 Btu/hr 6.84 "105 Btu/hr
1686 gal
1096 gal
(2.61 gal/min)
590 gal
(1.40 gal/min)
35%
0.19 gal/min
2/1min/40gal
0/0/0
1.16 gal/min
1.40 gal/min
1.28 gal/min
6.22'105 Btu/hr
1721 gal
1088 gal
(2.59 gal/min)
633 gal
(1.51 gal/min)
36.8%
0.28 gal/min
3/1min/40gal
0/0/0
1.04 gal/min
1690.3 gal
1054.1 gal
(2.51 gal/min)
636.1 gal
(1.51 gal/min)
37.6%
0.20 gal/min
2.4/1 min/35gal
0/0/0
1.18 gal/min
1.51 gal/min 1.51 gal/min
1.275 gal/min 1.35 gal/min
6.19'105 Btu/hr 6.55 "105 Btu/hr
Condensate
Flow During Daytime to
Process as Rinse Water:
(Average Flowrate)
'Flow During Daytime
to Boiler:
(Average Flowrate)
549.9 gal
(1.31 gal/min)
614.1 gal
(1.46 gal/min)
Boiler Data
Type-yrin Service-Measured Eff.:
586.8 gal
(1.40gal/min)
584.8 gal
(1.40 gal/min)
593 gal
(1.41 gal/min)
592 gal
(1.41 gal/min)
Columbia WL 180 - 3 yr in service - 67% to 68%
509 gal
(1.21 gal/min)
566 gal
(1.35 gal/min)
515 gal
(1.23 gal/min)
556 gal
(1.32 gal/min)
550.7 gal
(1.30 gal/min)
582.6 gal
(1.40 gal/min)
(continued)
-------
Table 2. Continued
Test Series
Date
Test Number
4/14/92
1
4/15/92
2
4/16/92
3
2
5/14/92
1
2
5/15/92
2
Five
Day
Average
Boiler Thermal Efficiency: 39%-41 %
(Btu/hr to Process Btu/hr
to Boiler)
Average Energy Input 17.1 *105
to Boiler:(Btu/hr)
Daily Boiler Energy $127
Costbased upon
$0.53 /1O5 Btu:
38%-40%
17.7*105
$127
38%-40%
17.7*105
$127
42%-44%
14.6*105
$104.7
42%-44%
14.6*105
$104.7
40%-42%
16.3*105
$118.1
Average Effluent Flowrate During Single Tank Filling Period of 25 Days Containing 18 Workdays @ 7 Hours: 3.00 gal/min.
Average Effluent Flowrate During First 3 Test Days (Excluding Bath Dumps): 3.36 gal/min.
Average Effluent Flowrate During First 3 Test Days (Including Bath Dumps): 3.32 gal/min.
Total Effluent Flow During Single Tank Filling Period of 25 Days Containing 18 Workdays @ 7 Hours: 22,700 gal.
Clarified Water Produced During the 25-Day Period: 19,700 gal Sludge Produced During the 25-Day Period: "3,000 gal.
* Boiler feed: during daytime - condensate; during nighttime - clarified water Boiler Feed Water Treatment Done Once a Day at 2 p.m.
"99% Water. Water Removed after Settling.
Table 3. Comparison of Installation and Operating Cost Data of the Past and Present Treatment Systems at Pioneer
Equipment
Previous System
Individual Treatment Tanks
Present Zerpol System^
Storage Tanks and Boiler
Chemicals, $/yr2)
Labor, Repair, Maintenance & Monitoring3)
Sludge + Salts Disposal, $/yr
Total Operating Costs4), $/yr
Installed Costs, $
D.I. system, Installed Cost, $
Flow, gal/day
Operation, day/yr
Years in service
Original flow, gal/day
Boiler energy cost
12,300 - 15,300
35,140
not available
47,440 - 50,440
65,000 (1975)
30,000
16,000 - 40,000
250
1975- 1981
40.0006)
(not included)
2,700-3,300
1,890
8,800
13,390 - 13.9905)
170,000(1981)
30,000
1,500-5,000
250
1981 to present
5,000
(not included)
1) Requires Deionized (D.I.) Water System.
2) Includes Chemicals for Boiler and D.I. Water System.
3) Based on Labor Costs of$17.5/hr Includes labor for D.I. Columns Backwash.
4) Costs of Chemicals, Operating Labor, Repair, Maintenance, and Monitoring.
5) Includes Disposal of Sludge and Salts.
6) The Previous System Could Only Function With Diluted Flow, Requiring Large Volumes of Water.
shops where the treated effluent and the
generated condensate can be recirculated
and reused for rinsing without impairing
product quality.
The Zerpol system works well for the
Pioneer metal finishing process which was
the subject of the one- month field evalua-
tion. During that period, acid and caustic
baths were intentionally dumped into the
system as part of the normal operation of
the facility. This did not result in any no-
ticeable product quality impairment. This
system should perform just as well for
shops with similar production and quality
requirements.
Because the entire effluent is captured
and collected in large capacity tanks prior
to recycling; 1) risk of accidental release
is reduced; 2) special operating permits
are not required, although local agencies
should also be consulted; 3) compliance
with effluent pretreatment standards is not
required; 4) timing of chemical addition
and processing is flexible; and 5) mainte-
nance emergencies are less frequent and
more easily managed than with other
waste management options. Also, there
seem to be no acute safety concerns.
Measured levels of hydrogen cyanide at
the effluent mixing tank and at the boiler
blowdown sump were extremely low, well
within the OSHA standards.
When the required equipment for the
zero discharge system is identified, its eco-
nomics and pollution reduction potential
should be compared with those of other
systems, such as:
• Zero discharge, low temperature
evaporative recovery and treatment
systems.
• Non-chemical wastewater treatment
system.
• Carbon absorption.
• Microfiltration, Ultrafiltration, Reverse
Osmosis.
• Ion Exchange.
• Electrowinning by itself or in combi-
nation with other treatment systems.
It should be noted that while it is true
that the Zerpol zero discharge system does
-------
not contribute to pollution at the site, this
does not mean that its recovered materi-
als do not contribute pollution to the envi-
ronment at the smelting facility. Identifying
and quantifying this pollution could not be
accomplished in this study because of the
reluctance of the smelting operation to
provide information, but should be consid-
ered in any life-cycle analysis of this and
related processes.
The results of this investigation demon-
strate that, at this facility, the Zerpol zero
discharge system eliminates the discharge
of an aqueous wastestream by allowing
recycling of most of the process water.
The system facilitates the removal of met-
als in a form that is suitable for metal
recovery. Salts from the boiler blowdown
are treated as wastes in a standard water
treatment facility. These positive factors
represent a reduction in the volume of
waste generated at the facility through a
series of process modifications and have
encouraged and facilitated source reduc-
tion initiatives at the facility.
The full report was submitted in fulfill-
ment of Assistance Agreement No. CR-
816142 by New Jersey Department of
Environmental Protection under the spon-
sorship of the U.S. Environmental Protec-
tion Agency.
Hanna J. Saqa and Daniel J. Watts are with New Jersey Institute of Technol-
ogy, Newark, NJ 07102; Mohammed Elsaady is with the New Jersey
Department of Environmental Protection and Energy, Trenton, NJ 08625;
and the EPA author, Johnny Springer (also the EPA Project Officer, see
below) is with the National Risk Management Research Laboratory, Cincin-
nati, OH 45268.
The complete report, entitled "Field Testing and Evaluation ofZerpoP Technol-
ogy at Pioneer Metal Finishing," (Order No. PB95-260238; Cost: $19.50,
subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
National Risk Management Research Laboratory
U. S. Environmental Protection Agency
Cincinnati, OH 45268
United States
Environmental Protection Agency
National Risk Management Research Laboratory (G-72)
Cincinnati, OH 45268
BULK RATE
POSTAGE & FEES PAID
EPA
PERMIT No. G-35
Official Business
Penalty for Private Use
$300
EPA/600/SR-95/126
------- |